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Kato Y, Ariyoshi K, Nohara Y, Matsunaga N, Shimauchi T, Shindo N, Nishimura A, Mi X, Kim SG, Ide T, Kawanishi E, Ojida A, Nakashima N, Mori Y, Nishida M. Inhibition of dynamin-related protein 1-filamin interaction improves systemic glucose metabolism. Br J Pharmacol 2024; 181:4328-4347. [PMID: 38986570 DOI: 10.1111/bph.16487] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2023] [Revised: 05/05/2024] [Accepted: 05/18/2024] [Indexed: 07/12/2024] Open
Abstract
BACKGROUND AND PURPOSE Maintaining mitochondrial quality is attracting attention as a new strategy to treat diabetes and diabetic complications. We previously reported that mitochondrial hyperfission by forming a protein complex between dynamin-related protein (Drp) 1 and filamin, mediates chronic heart failure and cilnidipine, initially developed as an L/N-type Ca2+ channel blocker, improves heart failure by inhibiting Drp1-filamin protein complex. We investigated whether cilnidipine improves hyperglycaemia of various diabetic mice models. EXPERIMENTAL APPROACH Retrospective analysis focusing on haemoglobin A1c (HbA1c) was performed in hypertensive and hyperglycaemic patients taking cilnidipine and amlodipine. After developing diabetic mice by streptozotocin (STZ) treatment, an osmotic pump including drug was implanted intraperitoneally, followed by weekly measurements of blood glucose levels. Mitochondrial morphology was analysed by electron microscopy. A Ca2+ channel-insensitive cilnidipine derivative (1,4-dihydropyridine [DHP]) was synthesized and its pharmacological effect was evaluated using obese (ob/ob) mice fed with high-fat diet (HFD). KEY RESULTS In patients, cilnidipine was superior to amlodipine in HbA1c lowering effect. Cilnidipine treatment improved systemic hyperglycaemia and mitochondrial morphological abnormalities in STZ-exposed mice, without lowering blood pressure. Cilnidipine failed to improve hyperglycaemia of ob/ob mice, with suppressing insulin secretion. 1,4-DHP improved hyperglycaemia and mitochondria abnormality in ob/ob mice fed HFD. 1,4-DHP and cilnidipine improved basal oxygen consumption rate of HepG2 cells cultured under 25 mM glucose. CONCLUSION AND IMPLICATIONS Inhibition of Drp1-filamin protein complex formation becomes a new strategy for type 2 diabetes treatment.
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Affiliation(s)
- Yuri Kato
- Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka, Japan
| | - Kohei Ariyoshi
- Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka, Japan
| | - Yasunobu Nohara
- Faculty of Advanced Science and Technology, Kumamoto University, Kumamoto, Japan
| | - Naoya Matsunaga
- Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka, Japan
| | - Tsukasa Shimauchi
- Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka, Japan
- Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
- National Institute for Physiological Sciences (NIPS), National Institutes of Natural Sciences, Okazaki, Aichi, Japan
- Exploratory Research Center on Life and Living Systems (ExCELLS), National Institutes of Natural Sciences, Okazaki, Aichi, Japan
| | - Naoya Shindo
- Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka, Japan
| | - Akiyuki Nishimura
- National Institute for Physiological Sciences (NIPS), National Institutes of Natural Sciences, Okazaki, Aichi, Japan
- Exploratory Research Center on Life and Living Systems (ExCELLS), National Institutes of Natural Sciences, Okazaki, Aichi, Japan
- SOKENDAI (The Graduate University for Advanced Studies), Okazaki, Aichi, Japan
| | - Xinya Mi
- Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka, Japan
| | - Sang Geon Kim
- College of Pharmacy, Dongguk University-Seoul, Goyang-si, South Korea
| | - Tomomi Ide
- Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Eiji Kawanishi
- Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka, Japan
| | - Akio Ojida
- Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka, Japan
| | - Naoki Nakashima
- Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Yasuo Mori
- Graduate School of Engineering, Kyoto University, Kyoto, Japan
| | - Motohiro Nishida
- Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka, Japan
- National Institute for Physiological Sciences (NIPS), National Institutes of Natural Sciences, Okazaki, Aichi, Japan
- Exploratory Research Center on Life and Living Systems (ExCELLS), National Institutes of Natural Sciences, Okazaki, Aichi, Japan
- SOKENDAI (The Graduate University for Advanced Studies), Okazaki, Aichi, Japan
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Gancheva S, Roden M, Castera L. Diabetes as a risk factor for MASH progression. Diabetes Res Clin Pract 2024; 217:111846. [PMID: 39245423 DOI: 10.1016/j.diabres.2024.111846] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/24/2024] [Revised: 08/28/2024] [Accepted: 09/03/2024] [Indexed: 09/10/2024]
Abstract
Non-alcoholic (now: metabolic) steatohepatitis (MASH) is the progressive inflammatory form of metabolic dysfunction-associated steatotic liver disease (MASLD), which often coexists and mutually interacts with type 2 diabetes (T2D), resulting in worse hepatic and cardiovascular outcomes. Understanding the intricate mechanisms of diabetes-related MASH progression is crucial for effective therapeutic strategies. This review delineates the multifaceted pathways involved in this interplay and explores potential therapeutic implications. The synergy between adipose tissue, gut microbiota, and hepatic alterations plays a pivotal role in disease progression. Adipose tissue dysfunction, particularly in the visceral depot, coupled with dysbiosis in the gut microbiota, exacerbates hepatic injury and insulin resistance. Hepatic lipid accumulation, oxidative stress, and endoplasmic reticulum stress further potentiate inflammation and fibrosis, contributing to disease severity. Dietary modification with weight reduction and exercise prove crucial in managing T2D-related MASH. Additionally, various well-known but also novel anti-hyperglycemic medications exhibit potential in reducing liver lipid content and, in some cases, improving MASH histology. Therapies targeting incretin receptors show promise in managing T2D-related MASH, while thyroid hormone receptor-β agonism has proven effective as a treatment of MASH and fibrosis.
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Affiliation(s)
- Sofiya Gancheva
- Department of Endocrinology and Diabetology, Medical Faculty and University Hospital, Heinrich-Heine University, Düsseldorf, Germany; Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research at Heinrich Heine University, Düsseldorf, Germany; German Center for Diabetes Research (DZD e.V.), Partner Düsseldorf, München-Neuherberg, Germany
| | - Michael Roden
- Department of Endocrinology and Diabetology, Medical Faculty and University Hospital, Heinrich-Heine University, Düsseldorf, Germany; Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research at Heinrich Heine University, Düsseldorf, Germany; German Center for Diabetes Research (DZD e.V.), Partner Düsseldorf, München-Neuherberg, Germany.
| | - Laurent Castera
- Department of Hepatology, Hôpital Beaujon, Assistance Publique-Hôpitaux de Paris, Clichy, France; Université Paris-Cité, INSERM UMR 1149, Centre de Recherche sur l'Inflammation Paris, Montmartre, Paris, France.
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Kahl S, Straßburger K, Pacini G, Trinks N, Pafili K, Mastrototaro L, Dewidar B, Sarabhai T, Trenkamp S, Esposito I, Schlensak M, Granderath FA, Roden M. Dysglycemia and liver lipid content determine the relationship of insulin resistance with hepatic OXPHOS capacity in obesity. J Hepatol 2024:S0168-8278(24)02490-5. [PMID: 39218222 DOI: 10.1016/j.jhep.2024.08.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/23/2023] [Revised: 08/14/2024] [Accepted: 08/15/2024] [Indexed: 09/04/2024]
Abstract
BACKGROUND & AIMS Hepatic mitochondrial respiration is higher in steatosis, but lower in overt type 2 diabetes. We hypothesized that hepatic OXPHOS capacity increases with a greater degree of insulin resistance in obesity, independent of other metabolic diseases. METHODS We analysed 65 humans without diabetes (BMI 50±7 kg/m2, HbA1c 5.5±0.4%) undergoing bariatric surgery. MASLD stages were assessed by histology, whole-body insulin sensitivity (PREDIcted-M index) by oral glucose tolerance tests, and maximal ADP-stimulated mitochondrial OXPHOS capacity by high-resolution respirometry of liver samples. RESULTS Prediabetes was present in 30 participants, and MASLD in 46 participants. Thereof, 25 had metabolic dysfunction-associated steatohepatitis (MASH), and seven had F2-F3 fibrosis. While simple regression did not detect an association of insulin sensitivity with hepatic OXPHOS capacity, interaction analyses revealed that the regression coefficient of OXPHOS capacity depended on fasting plasma glucose (FPG) and liver lipid content. Interestingly, the respective slopes were negative for FPG ≤100 mg/dl, but positive for FPG >100 mg/dl. Liver lipid content displayed similar behavior, with a threshold value of 24%. Post-challenge glycemia affected the association between insulin sensitivity and OXPHOS capacity normalized for citrate synthase activity. Presence of prediabetes affected hepatic insulin signaling, mitochondrial dynamics and fibrosis prevalence, while the presence of MASLD related to higher biomarkers of hepatic inflammation, cell damage and lipid peroxidation in people with normal glucose tolerance. CONCLUSIONS Rising liver lipid contents and plasma glucose concentrations, even in the non-diabetic range, are associated with a progressive decline of hepatic mitochondrial adaptation in people with obesity and insulin resistance. CLINTRIALS. GOV IDENTIFIER NCT01477957.
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Affiliation(s)
- Sabine Kahl
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research, Heinrich Heine University, Düsseldorf, Germany; German Center for Diabetes Research (DZD e.V.), Partner Düsseldorf, Germany; Department of Endocrinology and Diabetology, Medical Faculty and University Hospital Düsseldorf, Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany
| | - Klaus Straßburger
- German Center for Diabetes Research (DZD e.V.), Partner Düsseldorf, Germany; Institute for Biometrics and Epidemiology, German Diabetes Center, Leibniz Center for Diabetes Research, Heinrich Heine University, Düsseldorf, Germany
| | | | - Nina Trinks
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research, Heinrich Heine University, Düsseldorf, Germany; German Center for Diabetes Research (DZD e.V.), Partner Düsseldorf, Germany
| | - Kalliopi Pafili
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research, Heinrich Heine University, Düsseldorf, Germany; German Center for Diabetes Research (DZD e.V.), Partner Düsseldorf, Germany; Department of Endocrinology and Diabetology, Medical Faculty and University Hospital Düsseldorf, Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany
| | - Lucia Mastrototaro
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research, Heinrich Heine University, Düsseldorf, Germany; German Center for Diabetes Research (DZD e.V.), Partner Düsseldorf, Germany
| | - Bedair Dewidar
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research, Heinrich Heine University, Düsseldorf, Germany; German Center for Diabetes Research (DZD e.V.), Partner Düsseldorf, Germany
| | - Theresia Sarabhai
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research, Heinrich Heine University, Düsseldorf, Germany; German Center for Diabetes Research (DZD e.V.), Partner Düsseldorf, Germany; Department of Endocrinology and Diabetology, Medical Faculty and University Hospital Düsseldorf, Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany
| | - Sandra Trenkamp
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research, Heinrich Heine University, Düsseldorf, Germany; German Center for Diabetes Research (DZD e.V.), Partner Düsseldorf, Germany
| | - Irene Esposito
- Institute of Pathology, Medical Faculty, Heinrich-Heine University Düsseldorf, Düsseldorf, Germany
| | - Matthias Schlensak
- Adipositas- und Refluxzentrum, Krankenhaus Neuwerk, Mönchengladbach, Germany
| | - Frank A Granderath
- Adipositas- und Refluxzentrum, Krankenhaus Neuwerk, Mönchengladbach, Germany
| | - Michael Roden
- Department of Endocrinology and Diabetology, Medical Faculty and University Hospital Düsseldorf, Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany; Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research, Heinrich Heine University, Düsseldorf, Germany; German Center for Diabetes Research (DZD e.V.), Partner Düsseldorf, Germany.
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Petersen KF, Dufour S, Mehal WZ, Shulman GI. Glucagon promotes increased hepatic mitochondrial oxidation and pyruvate carboxylase flux in humans with fatty liver disease. Cell Metab 2024:S1550-4131(24)00325-5. [PMID: 39197461 DOI: 10.1016/j.cmet.2024.07.023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/25/2024] [Revised: 05/23/2024] [Accepted: 07/31/2024] [Indexed: 09/01/2024]
Abstract
We assessed in vivo rates of hepatic mitochondrial oxidation, gluconeogenesis, and β-hydroxybutyrate (β-OHB) turnover by positional isotopomer NMR tracer analysis (PINTA) in individuals with metabolic-dysfunction-associated steatotic liver (MASL) (fatty liver) and MASL disease (MASLD) (steatohepatitis) compared with BMI-matched control participants with no hepatic steatosis. Hepatic fat content was quantified by localized 1H magnetic resonance spectroscopy (MRS). We found that in vivo rates of hepatic mitochondrial oxidation were unaltered in the MASL and MASLD groups compared with the control group. A physiological increase in plasma glucagon concentrations increased in vivo rates of hepatic mitochondrial oxidation by 50%-75% in individuals with and without MASL and increased rates of glucose production by ∼50% in the MASL group, which could be attributed in part to an ∼30% increase in rates of mitochondrial pyruvate carboxylase flux. These results demonstrate that (1) rates of hepatic mitochondrial oxidation are not substantially altered in individuals with MASL and MASLD and (2) glucagon increases rates of hepatic mitochondrial oxidation.
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Affiliation(s)
- Kitt Falk Petersen
- Department of Internal Medicine, Yale School of Medicine, New Haven, CT, USA.
| | - Sylvie Dufour
- Department of Internal Medicine, Yale School of Medicine, New Haven, CT, USA
| | - Wajahat Z Mehal
- Department of Internal Medicine, Yale School of Medicine, New Haven, CT, USA; West Haven Medical Center, West Haven, CT, USA
| | - Gerald I Shulman
- Department of Internal Medicine, Yale School of Medicine, New Haven, CT, USA; Department of Cellular & Molecular Physiology, Yale School of Medicine, New Haven, CT, USA; Howard Hughes Medical Institute, Chevy Chase, MD, USA.
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Hu CQ, Hou T, Xiang R, Li X, Li J, Wang TT, Liu WJ, Hou S, Wang D, Zhao QH, Yu XX, Xu M, Liu XK, Chi YJ, Yang JC. PANX1-mediated ATP release confers FAM3A's suppression effects on hepatic gluconeogenesis and lipogenesis. Mil Med Res 2024; 11:41. [PMID: 38937853 PMCID: PMC11210080 DOI: 10.1186/s40779-024-00543-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/01/2023] [Accepted: 06/10/2024] [Indexed: 06/29/2024] Open
Abstract
BACKGROUND Extracellular adenosine triphosphate (ATP) is an important signal molecule. In previous studies, intensive research had revealed the crucial roles of family with sequence similarity 3 member A (FAM3A) in controlling hepatic glucolipid metabolism, islet β cell function, adipocyte differentiation, blood pressure, and other biological and pathophysiological processes. Although mitochondrial protein FAM3A plays crucial roles in the regulation of glucolipid metabolism via stimulating ATP release to activate P2 receptor pathways, its mechanism in promoting ATP release in hepatocytes remains unrevealed. METHODS db/db, high-fat diet (HFD)-fed, and global pannexin 1 (PANX1) knockout mice, as well as liver sections of individuals, were used in this study. Adenoviruses and adeno-associated viruses were utilized for in vivo gene overexpression or inhibition. To evaluate the metabolic status in mice, oral glucose tolerance test (OGTT), pyruvate tolerance test (PTT), insulin tolerance test (ITT), and magnetic resonance imaging (MRI) were conducted. Protein-protein interactions were determined by coimmunoprecipitation with mass spectrometry (MS) assays. RESULTS In livers of individuals and mice with steatosis, the expression of ATP-permeable channel PANX1 was increased (P < 0.01). Hepatic PANX1 overexpression ameliorated the dysregulated glucolipid metabolism in obese mice. Mice with hepatic PANX1 knockdown or global PANX1 knockout exhibited disturbed glucolipid metabolism. Restoration of hepatic PANX1 rescued the metabolic disorders of PANX1-deficient mice (P < 0.05). Mechanistically, ATP release is mediated by the PANX1-activated protein kinase B-forkhead box protein O1 (Akt-FOXO1) pathway to inhibit gluconeogenesis via P2Y receptors in hepatocytes. PANX1-mediated ATP release also activated calmodulin (CaM) (P < 0.01), which interacted with c-Jun N-terminal kinase (JNK) to inhibit its activity, thereby deactivating the transcription factor activator protein-1 (AP1) and repressing fatty acid synthase (FAS) expression and lipid synthesis (P < 0.05). FAM3A stimulated the expression of PANX1 via heat shock factor 1 (HSF1) in hepatocytes (P < 0.05). Notably, FAM3A overexpression failed to promote ATP release, inhibit the expression of gluconeogenic and lipogenic genes, and suppress gluconeogenesis and lipid deposition in PANX1-deficient hepatocytes and livers. CONCLUSIONS PANX1-mediated release of ATP plays a crucial role in maintaining hepatic glucolipid homeostasis, and it confers FAM3A's suppressive effects on hepatic gluconeogenesis and lipogenesis.
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Affiliation(s)
- Cheng-Qing Hu
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences/State Key Laboratory of Vascular Homeostasis and Remodeling/Center for Non-Coding RNA Medicine, Peking University Health Science Center, Beijing, 100191, China
- Department of Obstetrics and Gynecology, Peking University Third Hospital/National Clinical Research Center for Obstetrics and Gynecology, Beijing, 100191, China
| | - Tao Hou
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences/State Key Laboratory of Vascular Homeostasis and Remodeling/Center for Non-Coding RNA Medicine, Peking University Health Science Center, Beijing, 100191, China
| | - Rui Xiang
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences/State Key Laboratory of Vascular Homeostasis and Remodeling/Center for Non-Coding RNA Medicine, Peking University Health Science Center, Beijing, 100191, China
| | - Xin Li
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences/State Key Laboratory of Vascular Homeostasis and Remodeling/Center for Non-Coding RNA Medicine, Peking University Health Science Center, Beijing, 100191, China
| | - Jing Li
- Department of Endocrinology, Beijing Chao-Yang Hospital, Capital Medical University, Beijing, 100020, China
| | - Tian-Tian Wang
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences/State Key Laboratory of Vascular Homeostasis and Remodeling/Center for Non-Coding RNA Medicine, Peking University Health Science Center, Beijing, 100191, China
| | - Wen-Jun Liu
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences/State Key Laboratory of Vascular Homeostasis and Remodeling/Center for Non-Coding RNA Medicine, Peking University Health Science Center, Beijing, 100191, China
| | - Song Hou
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences/State Key Laboratory of Vascular Homeostasis and Remodeling/Center for Non-Coding RNA Medicine, Peking University Health Science Center, Beijing, 100191, China
| | - Di Wang
- Department of Central Laboratory and Institute of Clinical Molecular Biology, Peking University People's Hospital, Beijing, 100044, China
| | - Qing-He Zhao
- Department of Gastroenterology, Peking University People's Hospital, Beijing, 100044, China
| | - Xiao-Xing Yu
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences/State Key Laboratory of Vascular Homeostasis and Remodeling/Center for Non-Coding RNA Medicine, Peking University Health Science Center, Beijing, 100191, China
| | - Ming Xu
- Department of Cardiology, Institute of Vascular Medicine, Peking University Third Hospital/Key Laboratory of Molecular Cardiovascular Science of the Ministry of Education, Beijing, 100191, China
| | - Xing-Kai Liu
- Department of Hepatobiliary and Pancreatic Surgery, General Surgery Centre, the First Hospital of Jilin University, Changchun, 130061, China.
| | - Yu-Jing Chi
- Department of Central Laboratory and Institute of Clinical Molecular Biology, Peking University People's Hospital, Beijing, 100044, China.
- Department of Gastroenterology, Peking University People's Hospital, Beijing, 100044, China.
| | - Ji-Chun Yang
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences/State Key Laboratory of Vascular Homeostasis and Remodeling/Center for Non-Coding RNA Medicine, Peking University Health Science Center, Beijing, 100191, China.
- Department of Cardiology, Peking University Third Hospital, Beijing, 100191, China.
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Engin A. Nonalcoholic Fatty Liver Disease and Staging of Hepatic Fibrosis. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2024; 1460:539-574. [PMID: 39287864 DOI: 10.1007/978-3-031-63657-8_18] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/19/2024]
Abstract
Nonalcoholic fatty liver disease (NAFLD) is in parallel with the obesity epidemic, and it is the most common cause of liver diseases. The patients with severe insulin-resistant diabetes having high body mass index (BMI), high-grade adipose tissue insulin resistance, and high hepatocellular triacylglycerols (triglycerides; TAG) content develop hepatic fibrosis within a 5-year follow-up. Insulin resistance with the deficiency of insulin receptor substrate-2 (IRS-2)-associated phosphatidylinositol 3-kinase (PI3K) activity causes an increase in intracellular fatty acid-derived metabolites such as diacylglycerol (DAG), fatty acyl CoA, or ceramides. Lipotoxicity-related mechanism of NAFLD could be explained still best by the "double-hit" hypothesis. Insulin resistance is the major mechanism in the development and progression of NAFLD/nonalcoholic steatohepatitis (NASH). Metabolic oxidative stress, autophagy, and inflammation induce NASH progression. In the "first hit" the hepatic concentrations of diacylglycerol increase with an increase in saturated liver fat content in human NAFLD. Activities of mitochondrial respiratory chain complexes are decreased in the liver tissue of patients with NASH. Hepatocyte lipoapoptosis is a critical feature of NASH. In the "second hit," reduced glutathione levels due to oxidative stress lead to the overactivation of c-Jun N-terminal kinase (JNK)/c-Jun signaling that induces cell death in the steatotic liver. Accumulation of toxic levels of reactive oxygen species (ROS) is caused at least by two ineffectual cyclical pathways. First is the endoplasmic reticulum (ER) oxidoreductin (Ero1)-protein disulfide isomerase oxidation cycle through the downstream of the inner membrane mitochondrial oxidative metabolism and the second is the Kelch like-ECH-associated protein 1 (Keap1)-nuclear factor (erythroid-derived 2)-like 2 (Nrf2) pathways. In clinical practice, on ultrasonographic examination, the elevation of transaminases, γ-glutamyltransferase, and the aspartate transaminase to platelet ratio index indicates NAFLD. Fibrosis-4 index, NAFLD fibrosis score, and cytokeratin18 are used for grading steatosis, staging fibrosis, and discriminating the NASH from simple steatosis, respectively. In addition to ultrasonography, "controlled attenuation parameter," "magnetic resonance imaging proton-density fat fraction," "ultrasound-based elastography," "magnetic resonance elastography," "acoustic radiation force impulse elastography imaging," "two-dimensional shear-wave elastography with supersonic imagine," and "vibration-controlled transient elastography" are recommended as combined tests with serum markers in the clinical evaluation of NAFLD. However, to confirm the diagnosis of NAFLD, a liver biopsy is the gold standard. Insulin resistance-associated hyperinsulinemia directly accelerates fibrogenesis during NAFLD development. Although hepatocyte lipoapoptosis is a key driving force of fibrosis progression, hepatic stellate cells and extracellular matrix cells are major fibrogenic effectors. Thereby, these are pharmacological targets of therapies in developing hepatic fibrosis. Nonpharmacological management of NAFLD mainly consists of two alternatives: lifestyle modification and metabolic surgery. Many pharmacological agents that are thought to be effective in the treatment of NAFLD have been tried, but due to lack of ability to attenuate NAFLD, or adverse effects during the phase trials, the vast majority could not be licensed.
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Affiliation(s)
- Atilla Engin
- Faculty of Medicine, Department of General Surgery, Gazi University, Besevler, Ankara, Turkey.
- Mustafa Kemal Mah. 2137. Sok. 8/14, 06520, Cankaya, Ankara, Turkey.
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Arroum T, Pham L, Raisanen TE, Morse PT, Wan J, Bell J, Lax R, Saada A, Hüttemann M, Weksler-Zangen S. High Sucrose Diet-Induced Subunit I Tyrosine 304 Phosphorylation of Cytochrome c Oxidase Leads to Liver Mitochondrial Respiratory Dysfunction in the Cohen Diabetic Rat Model. Antioxidants (Basel) 2023; 13:19. [PMID: 38275639 PMCID: PMC10812566 DOI: 10.3390/antiox13010019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2023] [Revised: 12/13/2023] [Accepted: 12/19/2023] [Indexed: 01/27/2024] Open
Abstract
The mitochondrial oxidative phosphorylation process generates most of the cellular energy and free radicals in mammalian tissues. Both factors play a critical role in numerous human diseases that could be affected by reversible phosphorylation events that regulate the function and activity of the oxidative phosphorylation complexes. In this study, we analyzed liver mitochondria of Cohen diabetes-sensitive (CDs) and Cohen diabetes-resistant (CDr) rats, using blue native gel electrophoresis (BN-PAGE) in combination with mitochondrial activity measurements and a site-specific tyrosine phosphorylation implicated in inflammation, a known driver of diabetes pathology. We uncovered the presence of a specific inhibitory phosphorylation on tyrosine 304 of catalytic subunit I of dimeric cytochrome c oxidase (CcO, complex IV). Driven by a high sucrose diet in both CDr and CDs rats, Y304 phosphorylation, which occurs close to the catalytic oxygen binding site, correlates with a decrease in CcO activity and respiratory dysfunction in rat liver tissue under hyperglycemic conditions. We propose that this phosphorylation, specifically seen in dimeric CcO and induced by high sucrose diet-mediated inflammatory signaling, triggers enzymatic activity decline of complex IV dimers and the assembly of supercomplexes in liver tissue as a molecular mechanism underlying a (pre-)diabetic phenotype.
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Affiliation(s)
- Tasnim Arroum
- Center for Molecular Medicine and Genetics, Wayne State University, Detroit, MI 48201, USA; (T.A.); (L.P.); (T.E.R.); (P.T.M.); (J.W.); (J.B.)
| | - Lucynda Pham
- Center for Molecular Medicine and Genetics, Wayne State University, Detroit, MI 48201, USA; (T.A.); (L.P.); (T.E.R.); (P.T.M.); (J.W.); (J.B.)
| | - Taryn E. Raisanen
- Center for Molecular Medicine and Genetics, Wayne State University, Detroit, MI 48201, USA; (T.A.); (L.P.); (T.E.R.); (P.T.M.); (J.W.); (J.B.)
| | - Paul T. Morse
- Center for Molecular Medicine and Genetics, Wayne State University, Detroit, MI 48201, USA; (T.A.); (L.P.); (T.E.R.); (P.T.M.); (J.W.); (J.B.)
| | - Junmei Wan
- Center for Molecular Medicine and Genetics, Wayne State University, Detroit, MI 48201, USA; (T.A.); (L.P.); (T.E.R.); (P.T.M.); (J.W.); (J.B.)
| | - Jamie Bell
- Center for Molecular Medicine and Genetics, Wayne State University, Detroit, MI 48201, USA; (T.A.); (L.P.); (T.E.R.); (P.T.M.); (J.W.); (J.B.)
| | - Rachel Lax
- Faculty of Medicine Hebrew, University of Jerusalem, Jerusalem 9112102, Israel; (R.L.); (A.S.)
- The Hadassah Diabetes Center, Hadassah Medical Center, Jerusalem 9112102, Israel
- The Liver Research Laboratory, Hadassah Medical Center, Jerusalem 9112102, Israel
| | - Ann Saada
- Faculty of Medicine Hebrew, University of Jerusalem, Jerusalem 9112102, Israel; (R.L.); (A.S.)
- Department of Genetics, Hadassah Medical Center, Jerusalem 9112102, Israel
- Department of Medical Laboratory Sciences, Hadassah Academic College, Jerusalem 9101001, Israel
| | - Maik Hüttemann
- Center for Molecular Medicine and Genetics, Wayne State University, Detroit, MI 48201, USA; (T.A.); (L.P.); (T.E.R.); (P.T.M.); (J.W.); (J.B.)
- Department of Biochemistry, Microbiology, and Immunology, Wayne State University, Detroit, MI 48201, USA
| | - Sarah Weksler-Zangen
- Faculty of Medicine Hebrew, University of Jerusalem, Jerusalem 9112102, Israel; (R.L.); (A.S.)
- The Hadassah Diabetes Center, Hadassah Medical Center, Jerusalem 9112102, Israel
- The Liver Research Laboratory, Hadassah Medical Center, Jerusalem 9112102, Israel
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8
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Qiu B, Lawan A, Xirouchaki CE, Yi JS, Robert M, Zhang L, Brown W, Fernández-Hernando C, Yang X, Tiganis T, Bennett AM. MKP1 promotes nonalcoholic steatohepatitis by suppressing AMPK activity through LKB1 nuclear retention. Nat Commun 2023; 14:5405. [PMID: 37669951 PMCID: PMC10480499 DOI: 10.1038/s41467-023-41145-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2023] [Accepted: 08/24/2023] [Indexed: 09/07/2023] Open
Abstract
Nonalcoholic steatohepatitis (NASH) is triggered by hepatocyte death through activation of caspase 6, as a result of decreased adenosine monophosphate (AMP)-activated protein kinase-alpha (AMPKα) activity. Increased hepatocellular death promotes inflammation which drives hepatic fibrosis. We show that the nuclear-localized mitogen-activated protein kinase (MAPK) phosphatase-1 (MKP1) is upregulated in NASH patients and in NASH diet fed male mice. The focus of this work is to investigate whether and how MKP1 is involved in the development of NASH. Under NASH conditions increased oxidative stress, induces MKP1 expression leading to nuclear p38 MAPK dephosphorylation and decreases liver kinase B1 (LKB1) phosphorylation at a site required to promote LKB1 nuclear exit. Hepatic deletion of MKP1 in NASH diet fed male mice releases nuclear LKB1 into the cytoplasm to activate AMPKα and prevents hepatocellular death, inflammation and NASH. Hence, nuclear-localized MKP1-p38 MAPK-LKB1 signaling is required to suppress AMPKα which triggers hepatocyte death and the development of NASH.
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Affiliation(s)
- Bin Qiu
- Yale University School of Medicine, Department of Pharmacology, 333 Cedar Street, New Haven, CT, 06520, USA
- Yale University School of Medicine, Yale Center of Molecular and Systems Metabolism, New Haven, CT, 06520, USA
| | - Ahmed Lawan
- University of Alabama, Department of Biological Sciences, 301 Sparkman Drive, Huntsville, AL, 35899, USA
| | - Chrysovalantou E Xirouchaki
- Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC, 3800, Australia
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC, 3800, Australia
| | - Jae-Sung Yi
- Yale University School of Medicine, Department of Pharmacology, 333 Cedar Street, New Haven, CT, 06520, USA
- Yale University School of Medicine, Yale Center of Molecular and Systems Metabolism, New Haven, CT, 06520, USA
| | - Marie Robert
- Yale University School of Medicine, Department of Pathology, 300 Cedar Street, New Haven, CT, 06520, USA
| | - Lei Zhang
- Yale University School of Medicine, Department of Pharmacology, 333 Cedar Street, New Haven, CT, 06520, USA
- Yale University School of Medicine, Yale Center of Molecular and Systems Metabolism, New Haven, CT, 06520, USA
| | - Wendy Brown
- Monash University Department of Surgery, Alfred Hospital, Melbourne, Victoria, 3004, Australia
| | - Carlos Fernández-Hernando
- Yale University School of Medicine, Yale Center of Molecular and Systems Metabolism, New Haven, CT, 06520, USA
- Yale University School of Medicine, Department of Pathology, 300 Cedar Street, New Haven, CT, 06520, USA
- Yale University School of Medicine, Vascular Biology and Therapeutics Program, New Haven, CT, 06520, USA
- Department of Comparative Medicine, Yale University School of Medicine, New Haven, CT, USA
| | - Xiaoyong Yang
- Yale University School of Medicine, Yale Center of Molecular and Systems Metabolism, New Haven, CT, 06520, USA
- Department of Comparative Medicine, Yale University School of Medicine, New Haven, CT, USA
| | - Tony Tiganis
- Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC, 3800, Australia
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC, 3800, Australia
- Department of Comparative Medicine, Yale University School of Medicine, New Haven, CT, USA
| | - Anton M Bennett
- Yale University School of Medicine, Department of Pharmacology, 333 Cedar Street, New Haven, CT, 06520, USA.
- Yale University School of Medicine, Yale Center of Molecular and Systems Metabolism, New Haven, CT, 06520, USA.
- Yale University School of Medicine, Vascular Biology and Therapeutics Program, New Haven, CT, 06520, USA.
- Department of Comparative Medicine, Yale University School of Medicine, New Haven, CT, USA.
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9
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Chen L, Zhou M, Li H, Liu D, Liao P, Zong Y, Zhang C, Zou W, Gao J. Mitochondrial heterogeneity in diseases. Signal Transduct Target Ther 2023; 8:311. [PMID: 37607925 PMCID: PMC10444818 DOI: 10.1038/s41392-023-01546-w] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2022] [Revised: 02/21/2023] [Accepted: 06/13/2023] [Indexed: 08/24/2023] Open
Abstract
As key organelles involved in cellular metabolism, mitochondria frequently undergo adaptive changes in morphology, components and functions in response to various environmental stresses and cellular demands. Previous studies of mitochondria research have gradually evolved, from focusing on morphological change analysis to systematic multiomics, thereby revealing the mitochondrial variation between cells or within the mitochondrial population within a single cell. The phenomenon of mitochondrial variation features is defined as mitochondrial heterogeneity. Moreover, mitochondrial heterogeneity has been reported to influence a variety of physiological processes, including tissue homeostasis, tissue repair, immunoregulation, and tumor progression. Here, we comprehensively review the mitochondrial heterogeneity in different tissues under pathological states, involving variant features of mitochondrial DNA, RNA, protein and lipid components. Then, the mechanisms that contribute to mitochondrial heterogeneity are also summarized, such as the mutation of the mitochondrial genome and the import of mitochondrial proteins that result in the heterogeneity of mitochondrial DNA and protein components. Additionally, multiple perspectives are investigated to better comprehend the mysteries of mitochondrial heterogeneity between cells. Finally, we summarize the prospective mitochondrial heterogeneity-targeting therapies in terms of alleviating mitochondrial oxidative damage, reducing mitochondrial carbon stress and enhancing mitochondrial biogenesis to relieve various pathological conditions. The possibility of recent technological advances in targeted mitochondrial gene editing is also discussed.
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Affiliation(s)
- Long Chen
- State Key Laboratory of Cell Biology, CAS Center for Excellence in Molecular Cell Sciences, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai, 200031, China
| | - Mengnan Zhou
- Department of Pathogenic Biology, School of Basic Medical Science, China Medical University, Shenyang, 110001, China
| | - Hao Li
- Department of Orthopaedics, Shanghai Sixth People's Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, 200233, China
| | - Delin Liu
- Department of Orthopaedics, Shanghai Sixth People's Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, 200233, China
| | - Peng Liao
- Department of Orthopaedics, Shanghai Sixth People's Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, 200233, China
| | - Yao Zong
- Centre for Orthopaedic Research, Medical School, The University of Western Australia, Nedlands, WA, 6009, Australia
| | - Changqing Zhang
- Department of Orthopaedics, Shanghai Sixth People's Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, 200233, China.
| | - Weiguo Zou
- State Key Laboratory of Cell Biology, CAS Center for Excellence in Molecular Cell Sciences, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai, 200031, China.
- Institute of Microsurgery on Extremities, and Department of Orthopedic Surgery, Shanghai Sixth People's Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, 200233, China.
| | - Junjie Gao
- Department of Orthopaedics, Shanghai Sixth People's Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, 200233, China.
- Institute of Microsurgery on Extremities, and Department of Orthopedic Surgery, Shanghai Sixth People's Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, 200233, China.
- Shanghai Sixth People's Hospital Fujian, No. 16, Luoshan Section, Jinguang Road, Luoshan Street, Jinjiang City, Quanzhou, Fujian, China.
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10
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Qiu B, Lawan A, Xirouchaki CE, Yi JS, Robert M, Zhang L, Brown W, Fernández-Hernando C, Yang X, Tiganis T, Bennett AM. MKP1 promotes nonalcoholic steatohepatitis by suppressing AMPK activity through LKB1 nuclear retention. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.07.10.548263. [PMID: 37502892 PMCID: PMC10369865 DOI: 10.1101/2023.07.10.548263] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/29/2023]
Abstract
Nonalcoholic steatohepatitis (NASH) is triggered by hepatocyte death through activation of caspase 6, as a result of decreased adenosine monophosphate (AMP)-activated protein kinase-alpha (AMPKα) activity. Increased hepatocellular death promotes inflammation which drives hepatic fibrosis. We show that the nuclear-localized mitogen-activated protein kinase (MAPK) phosphatase-1 (MKP1) is upregulated in NASH patients and in NASH diet fed mice. The focus of this work was to investigate whether and how MKP1 is involved in the development of NASH. Under NASH conditions increased oxidative stress, induces MKP1 expression leading to nuclear p38 MAPK dephosphorylation and decreased liver kinase B1 (LKB1) phosphorylation at a site required to promote LKB1 nuclear exit. Hepatic deletion of MKP1 in NASH diet fed mice released nuclear LKB1 into the cytoplasm to activate AMPKα and prevent hepatocellular death, inflammation and NASH. Hence, nuclear-localized MKP1-p38 MAPK-LKB1 signaling is required to suppress AMPKα which triggers hepatocyte death and the development of NASH.
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11
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Wiafe YA, Afihene MY, Anto EO, Nmai RA, Amoah-Kumi L, Frimpong J, Dickson FD, Antwi SO, Roberts LR. Non-Alcoholic Fatty Liver Disease and Liver Fibrosis in Persons with Type 2 Diabetes Mellitus in Ghana: A Study of Prevalence, Severity, and Contributing Factors Using Transient Elastography. J Clin Med 2023; 12:jcm12113741. [PMID: 37297935 DOI: 10.3390/jcm12113741] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2023] [Revised: 05/24/2023] [Accepted: 05/26/2023] [Indexed: 06/12/2023] Open
Abstract
Type 2 diabetes mellitus (T2DM) is a metabolic disorder characterized by hyperglycemia, insulin resistance, and pancreatic islet cell dysfunction. T2DM is associated with non-alcoholic fatty liver disease (NAFLD) because of impaired glucose metabolism in both conditions. However, it is widely assumed that people with T2DM in sub-Saharan Africa (SSA) have a lower prevalence of NAFLD than in other parts of the world. With our recent access to transient elastography, we aimed to investigate the prevalence of, severity of, and contributing factors to NAFLD in persons with T2DM in Ghana. We performed a cross-sectional study recruiting 218 individuals with T2DM at the Kwadaso Seventh-Day Adventist and Mount Sinai Hospitals in the Ashanti region of Ghana using a simple randomized sampling technique. A structured questionnaire was used to obtain socio-demographic information, clinical history, exercise and other lifestyle factors, and anthropometric measurements. Transient elastography was performed using a FibroScan® machine to obtain the Controlled Attenuation Parameter (CAP) score and liver fibrosis score. The prevalence of NAFLD among Ghanaian T2DM participants was 51.4% (112/218), of whom 11.6% had significant liver fibrosis. An evaluation of the NAFLD group (n = 112) versus the non-NAFLD group (n = 106) revealed a higher BMI (28.7 vs. 25.2 kg/m2, p = 0.001), waist circumference (106.0 vs. 98.0 cm, p = 0.001), hip circumference (107.0 vs. 100.5 cm, p = 0.003), and waist-to-height ratio (0.66 vs. 0.62, p = 0.001) in T2DM patients with NAFLD compared to those without NAFLD. Being obese was an independent predictor of NAFLD in persons with T2DM than known history of hypertension and dyslipidaemia.
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Affiliation(s)
- Yaw Amo Wiafe
- Department of Medical Diagnostics, College of Health Sciences, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
| | - Mary Yeboah Afihene
- Department of Medicine, College of Health Sciences, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
| | - Enoch Odame Anto
- Department of Medical Diagnostics, College of Health Sciences, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
| | - Richmond Ashitey Nmai
- Department of Medical Diagnostics, College of Health Sciences, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
| | - Lois Amoah-Kumi
- Department of Medical Diagnostics, College of Health Sciences, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
| | - Joseph Frimpong
- Department of Medical Diagnostics, College of Health Sciences, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
| | | | - Samuel O Antwi
- Division of Epidemiology, Department of Quantitative Health Sciences, Mayo Clinic College of Medicine and Science, Jacksonville, FL 32224, USA
| | - Lewis R Roberts
- Division of Gastroenterology and Hepatology, Mayo Clinic College of Medicine and Science, Rochester, MN 55905, USA
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12
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Vilela WR, Bellozi PMQ, Picolo VL, Cavadas BN, Marques KVS, Pereira LTG, Guirao ARDY, Amato AA, Magalhães KG, Mortari MR, Medei EH, Goulart JT, de Bem AF. Early-life metabolic dysfunction impairs cognition and mitochondrial function in mice. J Nutr Biochem 2023; 117:109352. [PMID: 37061011 DOI: 10.1016/j.jnutbio.2023.109352] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Revised: 03/10/2023] [Accepted: 04/10/2023] [Indexed: 04/17/2023]
Abstract
The impact of overnutrition early in life is not restricted to the onset of cardiovascular and metabolic diseases, but also affects critical brain functions related to cognition. This study aimed to evaluate the relationship between peripheral metabolic and bioenergetic changes induced by a two-hit protocol and their impact on cognitive function in juvenile mice. Three-week-old male C57BL/6 mice received a high-fat diet (HFD) or control diet for 7 weeks, associated with 2 low doses of streptozotocin (STZ) or vehicle. Despite the absence of obesity, HFD+STZ impaired glucose metabolism and induced a trend towards cholesterol increase. The two-hit protocol impaired recognition and spatial memories in juvenile mice, without inducing a depressive-like behavior. HFD+STZ mice presented increased immunoreactivity for GFAP and a trend towards a decrease in NeuN in the hippocampus. The treatment caused a bioenergetic impairment in the hippocampus, characterized by a decrease in both O2 consumption related to ATP production and in the maximum respiratory capacity. The thermogenic capacity of brown adipose tissue was impaired by the two-hit protocol, here verified through the absence of a decrease in O2 consumption after uncoupled protein-1 inhibition and an increase in the reserve respiratory capacity. Impaired mitochondrial function was also observed in the liver of HFD+STZ juvenile mice, but not in their heart. These results indicate that exposure to HFD+STZ early in life has a detrimental impact on the bioenergetic and mitochondrial function of tissues with metabolic and thermogenic activities, which is likely related to hippocampal metabolic changes and cognitive impairment.
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Affiliation(s)
- Wembley Rodrigues Vilela
- Laboratory of Bioenergetics and Metabolism, Department of Physiological Sciences, Biology Institute, University of Brasilia, Federal District, Brazil
| | - Paula Maria Quaglio Bellozi
- Laboratory of Bioenergetics and Metabolism, Department of Physiological Sciences, Biology Institute, University of Brasilia, Federal District, Brazil
| | - Victor Luna Picolo
- Laboratory of Bioenergetics and Metabolism, Department of Physiological Sciences, Biology Institute, University of Brasilia, Federal District, Brazil
| | - Bruna Neves Cavadas
- Laboratory of Bioenergetics and Metabolism, Department of Physiological Sciences, Biology Institute, University of Brasilia, Federal District, Brazil
| | - Keila Valentina Silva Marques
- Laboratory of Bioenergetics and Metabolism, Department of Physiological Sciences, Biology Institute, University of Brasilia, Federal District, Brazil
| | | | - Ainhoa Rodriguez de Yurre Guirao
- Laboratory of Cardioimunology, Carlos Chagas Filho Institute of Biophysics, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Angélica Amorim Amato
- Laboratory of Molecular Pharmacology, School of Health Sciences, University of Brasilia, Brazil
| | - Kelly Grace Magalhães
- Laboratory of Immunology and Inflammation, Department of Physiological Sciences, Biology Institute, University of Brasilia, Federal District, Brazil
| | - Márcia Renata Mortari
- Laboratory of Neuropharmacology, Department of Physiological Sciences, Biology Institute, University of Brasilia, Federal District, Brazil
| | - Emiliano Horacio Medei
- Laboratory of Cardioimunology, Carlos Chagas Filho Institute of Biophysics, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Jair Trapé Goulart
- Laboratory of Bioenergetics and Metabolism, Department of Physiological Sciences, Biology Institute, University of Brasilia, Federal District, Brazil.
| | - Andreza Fabro de Bem
- Laboratory of Bioenergetics and Metabolism, Department of Physiological Sciences, Biology Institute, University of Brasilia, Federal District, Brazil; Center of Social and Affective Neuroscience, Department of Clinical and Experimental Medicine, Faculty of Medicine and Health, Linköping University, Linköping, Sweden.
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13
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Bouazza A, Fontaine E, Leverve X, Koceir EA. Interference of altered plasma trace elements profile with hyperhomocysteinemia and oxidative stress damage to insulin secretion dysfunction in Psammomys obesus: focus on the selenium. Arch Physiol Biochem 2023; 129:505-518. [PMID: 33171059 DOI: 10.1080/13813455.2020.1839501] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/06/2022]
Abstract
The objective of this study is to investigate the relationship between altered plasma trace elements, particularly selenium (Se), with Hyper-homocysteinemia (HhCys) as a predictive factor of insulin secretion dysfunction. The study is carried out on adult Psammomys obesus, divided in 4 experimental groups: (I) Normoglycemic/Normoinsulinemic; (II) Normoglycemic/Hyperinsulinemic; (III) Hyperglycaemic/Hyperinsulinemic and (IV) Hyperglycaemic/Insulin deficiency with ketoacidosis. The data showed that a drastic depletion of Se plasma levels is positively correlated with HhCys (>15 µmol/L; p < .001), concomitantly with decreased GPx activity, GSH levels, and GSH/GSSG ratio in group IV both in plasma and liver. In contrast, SOD activity is increased (p ≤ .001) in group IV both in plasma and liver. However, plasma Cu and Mn levels increased, while plasma Zn levels decreased in group IV (p < .001). Our study confirms the increase of plasma hCys levels seemed to be a major contributing factor to antioxidant capacities and alters the availability of selenium metabolism by interference with homocysteine synthesis in the insulin secretion deficiency stage.
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Affiliation(s)
- Asma Bouazza
- Bioenergetics and Intermediary Metabolism team, Laboratory of Biology and Organism Physiology, Biological Sciences faculty, University of Sciences and Technology Houari Boumediene (USTHB), Algiers, Algeria
| | - Eric Fontaine
- Laboratoire de Bioénergétique Fondamentale et Appliquée (LBFA), INSERM, Grenoble, France
| | - Xavier Leverve
- Laboratoire de Bioénergétique Fondamentale et Appliquée (LBFA), INSERM, Grenoble, France
| | - Elhadj-Ahmed Koceir
- Bioenergetics and Intermediary Metabolism team, Laboratory of Biology and Organism Physiology, Biological Sciences faculty, University of Sciences and Technology Houari Boumediene (USTHB), Algiers, Algeria
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14
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Fromenty B, Roden M. Mitochondrial alterations in fatty liver diseases. J Hepatol 2023; 78:415-429. [PMID: 36209983 DOI: 10.1016/j.jhep.2022.09.020] [Citation(s) in RCA: 90] [Impact Index Per Article: 90.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/10/2022] [Revised: 08/29/2022] [Accepted: 09/17/2022] [Indexed: 11/07/2022]
Abstract
Fatty liver diseases can result from common metabolic diseases, as well as from xenobiotic exposure and excessive alcohol use, all of which have been shown to exert toxic effects on hepatic mitochondrial functionality and dynamics. Invasive or complex methodology limits large-scale investigations of mitochondria in human livers. Nevertheless, abnormal mitochondrial function, such as impaired fatty acid oxidation and oxidative phosphorylation, drives oxidative stress and has been identified as an important feature of human steatohepatitis. On the other hand, hepatic mitochondria can be flexible and adapt to the ambient metabolic condition to prevent triglyceride and lipotoxin accumulation in obesity. Experience from studies on xenobiotics has provided important insights into the regulation of hepatic mitochondria. Increasing awareness of the joint presence of metabolic disease-related (lipotoxic) and alcohol-related liver diseases further highlights the need to better understand their mutual interaction and potentiation in disease progression. Recent clinical studies have assessed the effects of diets or bariatric surgery on hepatic mitochondria, which are also evolving as an interesting therapeutic target in non-alcoholic fatty liver disease. This review summarises the current knowledge on hepatic mitochondria with a focus on fatty liver diseases linked to obesity, type 2 diabetes and xenobiotics.
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Affiliation(s)
- Bernard Fromenty
- INSERM, Univ Rennes, INRAE, Institut NUMECAN (Nutrition Metabolisms and Cancer) UMR_A 1341, UMR_S 1241, F-35000, Rennes, France
| | - Michael Roden
- Department of Endocrinology and Diabetology, Medical Faculty and University Hospital Düsseldorf, Heinrich-Heine University Düsseldorf, Düsseldorf, Germany; Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research at Heinrich-Heine University Düsseldorf, Düsseldorf, Germany; German Center for Diabetes Research, Partner Düsseldorf, München-Neuherberg, Germany.
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15
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Yan H, Meng Y, Li X, Xiang R, Hou S, Wang J, Wang L, Yu X, Xu M, Chi Y, Yang J. FAM3A maintains metabolic homeostasis by interacting with F1-ATP synthase to regulate the activity and assembly of ATP synthase. Metabolism 2023; 139:155372. [PMID: 36470472 DOI: 10.1016/j.metabol.2022.155372] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/25/2022] [Revised: 11/12/2022] [Accepted: 11/25/2022] [Indexed: 12/12/2022]
Abstract
Reduced mitochondrial ATP synthase (ATPS) capacity plays crucial roles in the pathogenesis of metabolic disorders. However, there is currently no effective strategy for synchronously stimulating the expressions of ATPS key subunits to restore its assembly. This study determined the roles of mitochondrial protein FAM3A in regulating the activity and assembly of ATPS in hepatocytes. FAM3A is localized in mitochondrial matrix, where it interacts with F1-ATPS to initially activate ATP synthesis and release, and released ATP further activates P2 receptor-Akt-CREB pathway to induce FOXD3 expression. FOXD3 synchronously stimulates the transcriptions of ATPS key subunits and assembly genes to increase its assembly and capacity, augmenting ATP synthesis and inhibiting ROS production. FAM3A, FOXD3 and ATPS expressions were reduced in livers of diabetic mice and NAFLD patients. FOXD3 expression, ATPS capacity and ATP content were reduced in various tissues of FAM3A-deficient mice with dysregulated glucose and lipid metabolism. Hepatic FOXD3 activation increased ATPS assembly to ameliorate dysregulated glucose and lipid metabolism in obese mice. Hepatic FOXD3 inhibition or knockout reduced ATPS capacity to aggravate HFD-induced hyperglycemia and steatosis. In conclusion, FAM3A is an active ATPS component, and regulates its activity and assembly by activating FOXD3. Activating FAM3A-FOXD3 axis represents a viable strategy for restoring ATPS assembly to treat metabolic disorders.
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Affiliation(s)
- Han Yan
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Key Laboratory of Molecular Cardiovascular Science of the Ministry of Education, Center for Non-coding RNA Medicine, Peking University Health Science Center, Beijing 100191, China
| | - Yuhong Meng
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Key Laboratory of Molecular Cardiovascular Science of the Ministry of Education, Center for Non-coding RNA Medicine, Peking University Health Science Center, Beijing 100191, China
| | - Xin Li
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Key Laboratory of Molecular Cardiovascular Science of the Ministry of Education, Center for Non-coding RNA Medicine, Peking University Health Science Center, Beijing 100191, China
| | - Rui Xiang
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Key Laboratory of Molecular Cardiovascular Science of the Ministry of Education, Center for Non-coding RNA Medicine, Peking University Health Science Center, Beijing 100191, China
| | - Song Hou
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Key Laboratory of Molecular Cardiovascular Science of the Ministry of Education, Center for Non-coding RNA Medicine, Peking University Health Science Center, Beijing 100191, China
| | - Junpei Wang
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Key Laboratory of Molecular Cardiovascular Science of the Ministry of Education, Center for Non-coding RNA Medicine, Peking University Health Science Center, Beijing 100191, China
| | - Lin Wang
- Department of Hepatobiliary Surgery, Xi-Jing Hospital, Fourth Military Medical University, Xi'an 710032, China
| | - Xiaoxing Yu
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Key Laboratory of Molecular Cardiovascular Science of the Ministry of Education, Center for Non-coding RNA Medicine, Peking University Health Science Center, Beijing 100191, China
| | - Ming Xu
- Department of Cardiology, Institute of Vascular Medicine, Peking University Third Hospital, Key Laboratory of Molecular Cardiovascular Science of the Ministry of Education, Beijing 100191, China
| | - Yujing Chi
- Department of Central Laboratory and Institute of Clinical Molecular Biology, Peking University People's Hospital, Beijing 100044, China.
| | - Jichun Yang
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Key Laboratory of Molecular Cardiovascular Science of the Ministry of Education, Center for Non-coding RNA Medicine, Peking University Health Science Center, Beijing 100191, China.
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16
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Singh V. F 1F o adenosine triphosphate (ATP) synthase is a potential drug target in non-communicable diseases. Mol Biol Rep 2023; 50:3849-3862. [PMID: 36715790 DOI: 10.1007/s11033-023-08299-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2022] [Accepted: 01/19/2023] [Indexed: 01/31/2023]
Abstract
F1Fo adenosine triphosphate (ATP) synthase, also known as the complex V, is the central ATP-producing unit in the cells arranged in the mitochondrial and plasma membranes. F1Fo ATP synthase also regulates the central metabolic processes in the human body driven by proton motive force (Δp). Numerous studies have immensely contributed toward highlighting its regulation in improving energy homeostasis and maintaining mitochondrial integrity, which otherwise gets compromised in illnesses. Yet, its role in the implication of non-communicable diseases remains unknown. F1Fo ATP synthase dysregulation at gene level leads to reduced activity and delocalization in the cristae and plasma membranes, which is directly associated with non-communicable diseases: cardiovascular diseases, diabetes, neurodegenerative disorders, cancer, and renal diseases. Individual subunits of the F1Fo ATP synthase target ligand-based competitive or non-competitive inhibition. After performing a systematic literature review to understand its specific functions and its novel drug targets, the present article focuses on the central role of F1Fo ATP synthase in primary non-communicable diseases. Next, it discusses its involvement through various pathways and the effects of multiple inhibitors, activators, and modulators specific to non-communicable diseases with a futuristic outlook.
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Affiliation(s)
- Varsha Singh
- Centre for Life Sciences, Chitkara School of Health Sciences, Chitkara University, Rajpura, Punjab, 140401, India.
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17
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Active Glycogen Synthase in the Liver Prevents High-Fat Diet-Induced Glucose Intolerance, Decreases Food Intake, and Lowers Body Weight. Int J Mol Sci 2023; 24:ijms24032574. [PMID: 36768897 PMCID: PMC9917303 DOI: 10.3390/ijms24032574] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2022] [Revised: 01/19/2023] [Accepted: 01/23/2023] [Indexed: 01/31/2023] Open
Abstract
Many lines of evidence demonstrate a correlation between liver glycogen content and food intake. We previously demonstrated that mice overexpressing protein targeting to glycogen (PTG) specifically in the liver-which have increased glycogen content in this organ-are protected from high-fat diet (HFD)-induced obesity by reduced food intake. However, the use of PTG to increase liver glycogen implies certain limitations. PTG stimulates glycogen synthesis but also inhibits the enzyme responsible for glycogen degradation. Furthermore, as PTG is a regulatory subunit of protein phosphatase 1 (PP1), which regulates many cellular functions, its overexpression could have side effects beyond the regulation of glycogen metabolism. Therefore, it is necessary to determine whether the direct activation of glycogen synthesis, without affecting its degradation or other cellular functions, has the same effects. To this end, we generated mice overexpressing a non-inactivatable form of glycogen synthase (GS) specifically in the liver (9A-MGSAlb mice). Control and 9a-MGSAlb mice were fed a standard diet (SD) or HFD for 16 weeks. Glucose tolerance and feeding behavior were analyzed. 9A-MGSAlb mice showed an increase in hepatic glycogen in fed and fasting conditions. When fed an HFD, these animals preserved their hepatic energy state, had a reduced food intake, and presented a lower body weight and fat mass than control animals, without changes in energy expenditure. Furthermore, 9A-MGSAlb animals showed improved glucose tolerance when fed an SD or HFD. Moreover, liver triacylglycerol levels that were increased after HFD feeding were lower in these mice. These results confirm that increased liver glycogen stores contribute to decreased appetite and improve glucose tolerance in mice fed an HFD. On the basis of our findings, strategies to preserve hepatic glycogen stores emerge as potential treatments for obesity and hyperglycemia.
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Sarabhai T, Mastrototaro L, Kahl S, Bönhof GJ, Jonuscheit M, Bobrov P, Katsuyama H, Guthoff R, Wolkersdorfer M, Herder C, Meuth SG, Dreyer S, Roden M. Hyperbaric oxygen rapidly improves tissue-specific insulin sensitivity and mitochondrial capacity in humans with type 2 diabetes: a randomised placebo-controlled crossover trial. Diabetologia 2023; 66:57-69. [PMID: 36178534 PMCID: PMC9729133 DOI: 10.1007/s00125-022-05797-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/15/2022] [Accepted: 07/28/2022] [Indexed: 12/14/2022]
Abstract
AIMS/HYPOTHESIS Hyperbaric oxygen (HBO) therapy may improve hyperglycaemia in humans with type 2 diabetes, but underlying mechanisms are unclear. Our objective was to examine the glucometabolic effects of HBO on whole-body glucose disposal in humans with type 2 diabetes. METHODS In a randomised placebo-controlled crossover trial located at the German Diabetes Center, 12 male individuals with type 2 diabetes (age 18-75 years, BMI <35 kg/m2, HbA1c 42-75 mmol/mol [6-9%]), randomly allocated by one person, underwent 2-h HBO, once with 100% (240 kPa; HBO) and once with 21% oxygen (240 kPa; control, CON). Insulin sensitivity was assessed by hyperinsulinaemic-euglycaemic clamps with D-[6,6-2H2]glucose, hepatic and skeletal muscle energy metabolism were assessed by 1H/31P-magnetic resonance spectroscopy, while high-resolution respirometry measured skeletal muscle and white adipose tissue (WAT) mitochondrial capacity. All participants and people assessing the outcomes were blinded. RESULTS HBO decreased fasting blood glucose by 19% and increased whole-body, hepatic and WAT insulin sensitivity about one-third (p<0.05 vs CON). Upon HBO, hepatic γ-ATP concentrations doubled, mitochondrial respiratory control doubled in skeletal muscle and tripled in WAT (p<0.05 vs CON). HBO increased myocellular insulin-stimulated serine-473/threonine-308 phosphorylation of Akt but decreased basal inhibitory serine-1101 phosphorylation of IRS-1 and endoplasmic reticulum stress (p<0.05 vs CON). CONCLUSIONS/INTERPRETATION HBO-mediated improvement of insulin sensitivity likely results from decreased endoplasmic reticulum stress and increased mitochondrial capacity, possibly leading to low-dose reactive oxygen species-mediated mitohormesis in humans with type 2 diabetes. TRIAL REGISTRATION ClinicalTrials.gov NCT04219215 FUNDING: German Federal Ministry of Health, German Federal Ministry of Education and Research, North-Rhine Westfalia Ministry of Culture and Science, European-Regional-Development-Fund, German-Research-Foundation (DFG), Schmutzler Stiftung.
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Affiliation(s)
- Theresia Sarabhai
- Department of Endocrinology and Diabetology, Medical Faculty and University Hospital Düsseldorf, Heinrich-Heine-University, Düsseldorf, Germany
- Institute for Clinical Diabetology, German Diabetes Center (DDZ), Leibniz Institute for Diabetes Research at Heinrich-Heine-University, Düsseldorf, Germany
- German Center for Diabetes Research (DZD), Partner Düsseldorf, München-Neuherberg, Germany
| | - Lucia Mastrototaro
- Institute for Clinical Diabetology, German Diabetes Center (DDZ), Leibniz Institute for Diabetes Research at Heinrich-Heine-University, Düsseldorf, Germany
- German Center for Diabetes Research (DZD), Partner Düsseldorf, München-Neuherberg, Germany
| | - Sabine Kahl
- Institute for Clinical Diabetology, German Diabetes Center (DDZ), Leibniz Institute for Diabetes Research at Heinrich-Heine-University, Düsseldorf, Germany
- German Center for Diabetes Research (DZD), Partner Düsseldorf, München-Neuherberg, Germany
| | - Gidon J Bönhof
- Department of Endocrinology and Diabetology, Medical Faculty and University Hospital Düsseldorf, Heinrich-Heine-University, Düsseldorf, Germany
- Institute for Clinical Diabetology, German Diabetes Center (DDZ), Leibniz Institute for Diabetes Research at Heinrich-Heine-University, Düsseldorf, Germany
- German Center for Diabetes Research (DZD), Partner Düsseldorf, München-Neuherberg, Germany
| | - Marc Jonuscheit
- Institute for Clinical Diabetology, German Diabetes Center (DDZ), Leibniz Institute for Diabetes Research at Heinrich-Heine-University, Düsseldorf, Germany
- German Center for Diabetes Research (DZD), Partner Düsseldorf, München-Neuherberg, Germany
| | - Pavel Bobrov
- German Center for Diabetes Research (DZD), Partner Düsseldorf, München-Neuherberg, Germany
- Institute for Biometrics and Epidemiology, German Diabetes Center, Leibniz Center for Diabetes Research at Heinrich-Heine-University, Düsseldorf, Germany
| | - Hisayuki Katsuyama
- Institute for Clinical Diabetology, German Diabetes Center (DDZ), Leibniz Institute for Diabetes Research at Heinrich-Heine-University, Düsseldorf, Germany
- German Center for Diabetes Research (DZD), Partner Düsseldorf, München-Neuherberg, Germany
| | - Rainer Guthoff
- Department of Ophthalmology, Medical Faculty and University Hospital Düsseldorf, Heinrich-Heine-University, Düsseldorf, Germany
| | - Martin Wolkersdorfer
- Department of Production, Hospital Pharmacy, Landesapotheke Salzburg, Salzburg, Austria
| | - Christian Herder
- Department of Endocrinology and Diabetology, Medical Faculty and University Hospital Düsseldorf, Heinrich-Heine-University, Düsseldorf, Germany
- Institute for Clinical Diabetology, German Diabetes Center (DDZ), Leibniz Institute for Diabetes Research at Heinrich-Heine-University, Düsseldorf, Germany
- German Center for Diabetes Research (DZD), Partner Düsseldorf, München-Neuherberg, Germany
| | - Sven G Meuth
- Department of Neurology, Medical Faculty and University Hospital Düsseldorf, Heinrich-Heine-University, Düsseldorf, Germany
| | - Sven Dreyer
- Clinic for Orthopedics and Trauma Surgery, Medical Faculty and University Hospital Düsseldorf, Heinrich-Heine-University, Düsseldorf, Germany
| | - Michael Roden
- Department of Endocrinology and Diabetology, Medical Faculty and University Hospital Düsseldorf, Heinrich-Heine-University, Düsseldorf, Germany.
- Institute for Clinical Diabetology, German Diabetes Center (DDZ), Leibniz Institute for Diabetes Research at Heinrich-Heine-University, Düsseldorf, Germany.
- German Center for Diabetes Research (DZD), Partner Düsseldorf, München-Neuherberg, Germany.
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Alfadda NA, Aljuraiban GS, Awwad HM, Khaleel MS, Almaghamsi AM, Sherbeeni SM, Alqutub AN, Aldosary AS, Alfadda AA. Higher carbohydrate intake in relation to non-alcoholic fatty liver disease in patients with type 2 diabetes. Front Nutr 2022; 9:996004. [PMID: 36570126 PMCID: PMC9773196 DOI: 10.3389/fnut.2022.996004] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2022] [Accepted: 11/14/2022] [Indexed: 12/13/2022] Open
Abstract
Background Non-alcoholic fatty liver disease (NAFLD) is an overlooked complication of type 2 diabetes (T2D). Current recommendations for the management of NAFLD are mainly focused on weight reduction, overlooking the role of macronutrient composition. Although dietary carbohydrates play a major role in intrahepatic fat synthesis, their association with the progression of liver steatosis has not been fully investigated in patients with T2D. Aim To investigate the association between higher carbohydrate intake and the presence of liver steatosis in patients with T2D. Methods This cross-sectional study included men and women aged 18-60 years diagnosed with T2D. Anthropometric measurements, hepatic steatosis assessment using the controlled attenuation parameter (CAP), blood samples, and dietary data were analyzed. Participants were divided into two groups: NAFLD and NAFLD-free. A two-sample t-test was used to evaluate the differences between the two groups. Stepwise multiple linear regression models adjusted for potential confounders were used to determine the association between CAP values and higher carbohydrate intake. Results In total, 358 participants were included. NAFLD was present in 79.3% of the participants. Body mass index, waist circumference, ALT, HbA1c, and triglycerides showed direct, while HDL-Cholesterol revealed inverse associations with CAP values. No significant relationship was found between carbohydrate intake and steatosis in the total study sample; however, multiple linear regression analysis revealed a significant relationship between carbohydrate intake and CAP values in patients aged ≤50 years. Conclusion In patients with T2D, higher carbohydrate intake was associated with liver steatosis in those aged 50 years and below. Further studies are required to confirm the causality between carbohydrate intake and liver steatosis.
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Affiliation(s)
- Nora A. Alfadda
- Department of Community Health Sciences, College of Applied Medical Sciences, King Saud University, Riyadh, Saudi Arabia
| | - Ghadeer S. Aljuraiban
- Department of Community Health Sciences, College of Applied Medical Sciences, King Saud University, Riyadh, Saudi Arabia
| | - Hadeel M. Awwad
- Obesity Research Center, College of Medicine, King Saud University, Riyadh, Saudi Arabia
| | - Mohammad S. Khaleel
- Obesity Research Center, College of Medicine, King Saud University, Riyadh, Saudi Arabia
| | | | | | - Adel N. Alqutub
- Department of Gastroenterology and Hepatology, King Fahad Medical City, Riyadh, Saudi Arabia
| | - Abdullah S. Aldosary
- Department of Medical Imaging Administration, King Fahad Medical City, Riyadh, Saudi Arabia
| | - Assim A. Alfadda
- Obesity Research Center, College of Medicine, King Saud University, Riyadh, Saudi Arabia,Department of Medicine, College of Medicine, King Saud University, Riyadh, Saudi Arabia,*Correspondence: Assim A. Alfadda,
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20
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Moore MP, Cunningham RP, Meers GM, Johnson SA, Wheeler AA, Ganga RR, Spencer NM, Pitt JB, Diaz-Arias A, Swi AIA, Hammoud GM, Ibdah JA, Parks EJ, Rector RS. Compromised hepatic mitochondrial fatty acid oxidation and reduced markers of mitochondrial turnover in human NAFLD. Hepatology 2022; 76:1452-1465. [PMID: 35000203 PMCID: PMC9270503 DOI: 10.1002/hep.32324] [Citation(s) in RCA: 99] [Impact Index Per Article: 49.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
BACKGROUND AND AIMS NAFLD and its more-advanced form, steatohepatitis (NASH), is associated with obesity and is an independent risk factor for cardiovascular, liver-related, and all-cause mortality. Available human data examining hepatic mitochondrial fatty acid oxidation (FAO) and hepatic mitochondrial turnover in NAFLD and NASH are scant. APPROACH AND RESULTS To investigate this relationship, liver biopsies were obtained from patients with obesity undergoing bariatric surgery and data clustered into four groups based on hepatic histopathological classification: Control (CTRL; no disease); NAFL (steatosis only); Borderline-NASH (steatosis with lobular inflammation or hepatocellular ballooning); and Definite-NASH (D-NASH; steatosis, lobular inflammation, and hepatocellular ballooning). Hepatic mitochondrial complete FAO to CO2 and the rate-limiting enzyme in β-oxidation (β-hydroxyacyl-CoA dehydrogenase activity) were reduced by ~40%-50% with D-NASH compared with CTRL. This corresponded with increased hepatic mitochondrial reactive oxygen species production, as well as dramatic reductions in markers of mitochondrial biogenesis, autophagy, mitophagy, fission, and fusion in NAFL and NASH. CONCLUSIONS These findings suggest that compromised hepatic FAO and mitochondrial turnover are intimately linked to increasing NAFLD severity in patients with obesity.
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Affiliation(s)
- Mary P. Moore
- Research Service, Harry S Truman Memorial Veterans Medical Center, Columbia, MO, USA, 65201
- Department of Nutrition and Exercise Physiology, University of Missouri, Columbia, MO, USA, 65211
| | - Rory P. Cunningham
- Research Service, Harry S Truman Memorial Veterans Medical Center, Columbia, MO, USA, 65201
- Department of Nutrition and Exercise Physiology, University of Missouri, Columbia, MO, USA, 65211
| | - Grace M. Meers
- Research Service, Harry S Truman Memorial Veterans Medical Center, Columbia, MO, USA, 65201
- Department of Nutrition and Exercise Physiology, University of Missouri, Columbia, MO, USA, 65211
| | - Sarah A. Johnson
- Research Service, Harry S Truman Memorial Veterans Medical Center, Columbia, MO, USA, 65201
- Department of Medicine-Division of Gastroenterology and Hepatology, University of Missouri, Columbia MO, USA, 65211
| | - Andrew A. Wheeler
- Department of Surgery, University of Missouri, Columbia MO, USA, 65211
| | - Rama R. Ganga
- Department of Surgery, University of Missouri, Columbia MO, USA, 65211
| | - Nicole M. Spencer
- Department of Surgery, University of Missouri, Columbia MO, USA, 65211
| | - James B. Pitt
- Department of Surgery, University of Missouri, Columbia MO, USA, 65211
| | | | - Ahmed I. A. Swi
- Department of Medicine-Division of Gastroenterology and Hepatology, University of Missouri, Columbia MO, USA, 65211
| | - Ghassan M. Hammoud
- Department of Medicine-Division of Gastroenterology and Hepatology, University of Missouri, Columbia MO, USA, 65211
| | - Jamal A. Ibdah
- Research Service, Harry S Truman Memorial Veterans Medical Center, Columbia, MO, USA, 65201
- Department of Nutrition and Exercise Physiology, University of Missouri, Columbia, MO, USA, 65211
- Department of Medicine-Division of Gastroenterology and Hepatology, University of Missouri, Columbia MO, USA, 65211
| | - Elizabeth J. Parks
- Department of Nutrition and Exercise Physiology, University of Missouri, Columbia, MO, USA, 65211
- Department of Medicine-Division of Gastroenterology and Hepatology, University of Missouri, Columbia MO, USA, 65211
| | - R. Scott Rector
- Research Service, Harry S Truman Memorial Veterans Medical Center, Columbia, MO, USA, 65201
- Department of Nutrition and Exercise Physiology, University of Missouri, Columbia, MO, USA, 65211
- Department of Medicine-Division of Gastroenterology and Hepatology, University of Missouri, Columbia MO, USA, 65211
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21
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Legaki AI, Moustakas II, Sikorska M, Papadopoulos G, Velliou RI, Chatzigeorgiou A. Hepatocyte Mitochondrial Dynamics and Bioenergetics in Obesity-Related Non-Alcoholic Fatty Liver Disease. Curr Obes Rep 2022; 11:126-143. [PMID: 35501558 PMCID: PMC9399061 DOI: 10.1007/s13679-022-00473-1] [Citation(s) in RCA: 39] [Impact Index Per Article: 19.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 01/26/2022] [Indexed: 02/07/2023]
Abstract
PURPOSE OF THE REVIEW Mitochondrial dysfunction has long been proposed to play a crucial role in the pathogenesis of a considerable number of disorders, such as neurodegeneration, cancer, cardiovascular, and metabolic disorders, including obesity-related insulin resistance and non-alcoholic fatty liver disease (NAFLD). Mitochondria are highly dynamic organelles that undergo functional and structural adaptations to meet the metabolic requirements of the cell. Alterations in nutrient availability or cellular energy needs can modify their formation through biogenesis and the opposite processes of fission and fusion, the fragmentation, and connection of mitochondrial network areas respectively. Herein, we review and discuss the current literature on the significance of mitochondrial adaptations in obesity and metabolic dysregulation, emphasizing on the role of hepatocyte mitochondrial flexibility in obesity and NAFLD. RECENT FINDINGS Accumulating evidence suggests the involvement of mitochondrial morphology and bioenergetics dysregulations to the emergence of NAFLD and its progress to non-alcoholic steatohepatitis (NASH). Most relevant data suggests that changes in liver mitochondrial dynamics and bioenergetics hold a key role in the pathogenesis of NAFLD. During obesity and NAFLD, oxidative stress occurs due to the excessive production of ROS, leading to mitochondrial dysfunction. As a result, mitochondria become incompetent and uncoupled from respiratory chain activities, further promoting hepatic fat accumulation, while leading to liver inflammation, insulin resistance, and disease's deterioration. Elucidation of the mechanisms leading to dysfunctional mitochondrial activity of the hepatocytes during NAFLD is of predominant importance for the development of novel therapeutic approaches towards the treatment of this metabolic disorder.
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Affiliation(s)
- Aigli-Ioanna Legaki
- Department of Physiology, Medical School, National and Kapodistrian University of Athens, 75 Mikras Asias Str, 11527 Athens, Greece
| | - Ioannis I. Moustakas
- Department of Physiology, Medical School, National and Kapodistrian University of Athens, 75 Mikras Asias Str, 11527 Athens, Greece
| | - Michalina Sikorska
- Department of Physiology, Medical School, National and Kapodistrian University of Athens, 75 Mikras Asias Str, 11527 Athens, Greece
| | - Grigorios Papadopoulos
- Department of Physiology, Medical School, National and Kapodistrian University of Athens, 75 Mikras Asias Str, 11527 Athens, Greece
| | - Rallia-Iliana Velliou
- Department of Physiology, Medical School, National and Kapodistrian University of Athens, 75 Mikras Asias Str, 11527 Athens, Greece
| | - Antonios Chatzigeorgiou
- Department of Physiology, Medical School, National and Kapodistrian University of Athens, 75 Mikras Asias Str, 11527 Athens, Greece
- Institute for Clinical Chemistry and Laboratory Medicine, University Clinic Carl Gustav Carus, Technische Universität Dresden, Fetscherstrasse 74, 01307 Dresden, Germany
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22
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Li J, Yan H, Xiang R, Yang W, Ye J, Yin R, Yang J, Chi Y. ATP Secretion and Metabolism in Regulating Pancreatic Beta Cell Functions and Hepatic Glycolipid Metabolism. Front Physiol 2022; 13:918042. [PMID: 35800345 PMCID: PMC9253475 DOI: 10.3389/fphys.2022.918042] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2022] [Accepted: 05/30/2022] [Indexed: 11/13/2022] Open
Abstract
Diabetes (DM), especially type 2 diabetes (T2DM) has become one of the major diseases severely threatening public health worldwide. Islet beta cell dysfunctions and peripheral insulin resistance including liver and muscle metabolic disorder play decisive roles in the pathogenesis of T2DM. Particularly, increased hepatic gluconeogenesis due to insulin deficiency or resistance is the central event in the development of fasting hyperglycemia. To maintain or restore the functions of islet beta cells and suppress hepatic gluconeogenesis is crucial for delaying or even stopping the progression of T2DM and diabetic complications. As the key energy outcome of mitochondrial oxidative phosphorylation, adenosine triphosphate (ATP) plays vital roles in the process of almost all the biological activities including metabolic regulation. Cellular adenosine triphosphate participates intracellular energy transfer in all forms of life. Recently, it had also been revealed that ATP can be released by islet beta cells and hepatocytes, and the released ATP and its degraded products including ADP, AMP and adenosine act as important signaling molecules to regulate islet beta cell functions and hepatic glycolipid metabolism via the activation of P2 receptors (ATP receptors). In this review, the latest findings regarding the roles and mechanisms of intracellular and extracellular ATP in regulating islet functions and hepatic glycolipid metabolism would be briefly summarized and discussed.
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Affiliation(s)
- Jing Li
- Department of Endocrinology, Beijing Chao-Yang Hospital, Capital Medical University, Beijing, China
| | - Han Yan
- Key Laboratory of Cardiovascular Science of the Ministry of Education, Center for Non-coding RNA Medicine, Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, China
| | - Rui Xiang
- Key Laboratory of Cardiovascular Science of the Ministry of Education, Center for Non-coding RNA Medicine, Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, China
| | - Weili Yang
- Beijing Key Laboratory of Diabetes Research and Care, Beijing Tongren Hospital, Capital Medical University, Beijing, China
| | - Jingjing Ye
- Department of Central Laboratory and Institute of Clinical Molecular Biology, Peking University People’s Hospital, Beijing, China
- Key Laboratory of Trauma and Neural Regeneration (Peking University), National Center for Trauma Medicine, Trauma Medicine Center, Peking University People’s Hospital, Beijing, China
| | - Ruili Yin
- Beijing Key Laboratory of Diabetes Prevention and Research, Center for Endocrine Metabolic and Immune Disease, Beijing Luhe Hospital, Capital Medical University, Beijing, China
| | - Jichun Yang
- Key Laboratory of Cardiovascular Science of the Ministry of Education, Center for Non-coding RNA Medicine, Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, China
- *Correspondence: Jichun Yang, ; Yujing Chi,
| | - Yujing Chi
- Department of Central Laboratory and Institute of Clinical Molecular Biology, Peking University People’s Hospital, Beijing, China
- *Correspondence: Jichun Yang, ; Yujing Chi,
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A multi-omics analysis reveals that the lysine deacetylase ABHD14B influences glucose metabolism in mammals. J Biol Chem 2022; 298:102128. [PMID: 35700823 PMCID: PMC9270251 DOI: 10.1016/j.jbc.2022.102128] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2022] [Revised: 06/08/2022] [Accepted: 06/09/2022] [Indexed: 11/30/2022] Open
Abstract
The sirtuins and histone deacetylases are the best characterized members of the lysine deacetylase (KDAC) enzyme family. Recently, we annotated the “orphan” enzyme ABHD14B (α/β-hydrolase domain containing protein # 14B) as a novel KDAC and showed this enzyme’s ability to transfer an acetyl-group from protein lysine residue(s) to coenzyme-A to yield acetyl-coenzyme-A, thereby, expanding the repertoire of this enzyme family. However, the role of ABHD14B in metabolic processes is not fully elucidated. Here, we investigated the role of this enzyme using mammalian cell knockdowns in a combined transcriptomics and metabolomics analysis. We found from these complementary experiments in vivo that the loss of ABHD14B results in significantly altered glucose metabolism, specifically the decreased flux of glucose through glycolysis and the citric acid cycle. Further, we show that depleting hepatic ABHD14B in mice also results in defective systemic glucose metabolism, particularly during fasting. Taken together, our findings illuminate the important metabolic functions that the KDAC ABHD14B plays in mammalian physiology and poses new questions regarding the role of this hitherto cryptic metabolism-regulating enzyme.
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Molecular Basis of Irisin Regulating the Effects of Exercise on Insulin Resistance. APPLIED SCIENCES-BASEL 2022. [DOI: 10.3390/app12125837] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Insulin resistance is recognized as one major feature of metabolic syndrome, and frequently emerges as a difficult problem encountered during long-term pharmacological treatment of diabetes. Insulin resistance often causes organs or tissues, such as skeletal muscle, adipose, and liver, to become less responsive or resistant to insulin. Exercise can promote the physiological function of those organs and tissues and benefits insulin action via increasing insulin receptor sensitivity, glucose uptake, and mitochondrial function. This is done by decreasing adipose tissue deposition, inflammatory cytokines, and oxidative stress. However, understanding the mechanism that regulates the interaction between exercise and insulin function becomes a challenging task. As a novel myokine, irisin is activated by exercise, released from the muscle, and affects multi-organ functions. Recent evidence indicates that it can promote glucose uptake, improve mitochondrial function, alleviate obesity, and decrease inflammation, as a result leading to the improvement of insulin action. We here will review the current evidence concerning the signaling pathways by which irisin regulates the effect of exercise on the up-regulation of insulin action in humans and animals.
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25
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Dietary lipid droplet structure in postnatal life improves hepatic energy and lipid metabolism in a mouse model for postnatal programming. Pharmacol Res 2022; 179:106193. [DOI: 10.1016/j.phrs.2022.106193] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/10/2021] [Revised: 03/09/2022] [Accepted: 03/24/2022] [Indexed: 11/23/2022]
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Guerra S, Mocciaro G, Gastaldelli A. Adipose tissue insulin resistance and lipidome alterations as the characterizing factors of non-alcoholic steatohepatitis. Eur J Clin Invest 2022; 52:e13695. [PMID: 34695228 DOI: 10.1111/eci.13695] [Citation(s) in RCA: 28] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 09/16/2021] [Accepted: 10/15/2021] [Indexed: 12/13/2022]
Abstract
BACKGROUND The prevalence of non-alcoholic fatty liver disease (NAFLD) is now 25% in the general population but increases to more than 55% in subjects with obesity and/or type 2 diabetes. Simple steatosis (NAFL) can develop into more severe forms, that is non-alcoholic steatohepatitis (NASH), cirrhosis and hepatocellular carcinoma leading to death. METHODS In this narrative review, we have discussed the current knowledge in the pathophysiology of fatty liver disease, including both metabolic and non-metabolic factors, insulin resistance, mitochondrial function, as well as the markers of liver damage, giving attention to the alterations in lipid metabolism and production of lipotoxic lipids. RESULTS Insulin resistance, particularly in the adipose tissue, is the main driver of NAFLD due to the excess release of fatty acids. Lipidome analyses have shown that several lipids, including DAGs and ceramides, and especially if they contain saturated lipids, act as bioactive compounds, toxic to the cells. Lipids can also affect mitochondrial function. Not only lipids, but also amino acid metabolism is impaired in NAFL/NASH, and some amino acids, as branched-chain and aromatic amino acids, glutamate, serine and glycine, have been linked to impaired metabolism, insulin resistance and severity of NAFLD and serine is a precursor of ceramides. CONCLUSIONS The measurement of lipotoxic species and adipose tissue dysfunction can help to identify individuals at risk of progression to NASH.
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Affiliation(s)
- Sara Guerra
- Institute of Clinical Physiology (IFC), National Research Council (CNR), Pisa, Italy.,Sant'Anna School of Advanced Studies, Pisa, Italy
| | - Gabriele Mocciaro
- Institute of Clinical Physiology (IFC), National Research Council (CNR), Pisa, Italy
| | - Amalia Gastaldelli
- Institute of Clinical Physiology (IFC), National Research Council (CNR), Pisa, Italy.,Sant'Anna School of Advanced Studies, Pisa, Italy
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Abstract
Non-alcoholic fatty liver disease (NAFLD) is emerging as the most common chronic liver disease worldwide. It refers to a range of liver conditions affecting people who drink little or no alcohol. NAFLD comprises non-alcoholic fatty liver and non-alcoholic steatohepatitis (NASH), the more aggressive form of NAFLD. NASH is featured by steatosis, lobular inflammation, hepatocyte injury, and various degrees of fibrosis. Although much progress has been made over the past decades, the pathogenic mechanism of NAFLD remains to be fully elucidated. Hepatocyte nuclear factor 4α (HNF4α) is a nuclear hormone receptor that is highly expressed in hepatocytes. Hepatic HNF4α expression is markedly reduced in NAFLD patients and mouse models of NASH. HNF4α has been shown to regulate bile acid, lipid, glucose, and drug metabolism. In this review, we summarize the recent advances in the understanding of the pathogenesis of NAFLD with a focus on the regulation of HNF4α and the role of hepatic HNF4α in NAFLD. Several lines of evidence have shown that hepatic HNF4α plays a key role in the initiation and progression of NAFLD. Recent data suggest that hepatic HNF4α may be a promising target for treatment of NAFLD.
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Huang YC, Hsu SM, Shie FS, Shiao YJ, Chao LJ, Chen HW, Yao HH, Chien MA, Lin CC, Tsay HJ. Reduced mitochondria membrane potential and lysosomal acidification are associated with decreased oligomeric Aβ degradation induced by hyperglycemia: A study of mixed glia cultures. PLoS One 2022; 17:e0260966. [PMID: 35073330 PMCID: PMC8786178 DOI: 10.1371/journal.pone.0260966] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2021] [Accepted: 11/20/2021] [Indexed: 01/21/2023] Open
Abstract
Diabetes is a risk factor for Alzheimer’s disease (AD), a chronic neurodegenerative disease. We and others have shown prediabetes, including hyperglycemia and obesity induced by high fat and high sucrose diets, is associated with exacerbated amyloid beta (Aβ) accumulation and cognitive impairment in AD transgenic mice. However, whether hyperglycemia reduce glial clearance of oligomeric amyloid-β (oAβ), the most neurotoxic Aβ aggregate, remains unclear. Mixed glial cultures simulating the coexistence of astrocytes and microglia in the neural microenvironment were established to investigate glial clearance of oAβ under normoglycemia and chronic hyperglycemia. Ramified microglia and low IL-1β release were observed in mixed glia cultures. In contrast, amoeboid-like microglia and higher IL-1β release were observed in primary microglia cultures. APPswe/PS1dE9 transgenic mice are a commonly used AD mouse model. Microglia close to senile plaques in APPswe/PS1dE9 transgenic mice exposed to normoglycemia or chronic hyperglycemia exhibited an amoeboid-like morphology; other microglia were ramified. Therefore, mixed glia cultures reproduce the in vivo ramified microglial morphology. To investigate the impact of sustained high-glucose conditions on glial oAβ clearance, mixed glia were cultured in media containing 5.5 mM glucose (normal glucose, NG) or 25 mM glucose (high glucose, HG) for 16 days. Compared to NG, HG reduced the steady-state level of oAβ puncta internalized by microglia and astrocytes and decreased oAβ degradation kinetics. Furthermore, the lysosomal acidification and lysosomal hydrolysis activity of microglia and astrocytes were lower in HG with and without oAβ treatment than NG. Moreover, HG reduced mitochondrial membrane potential and ATP levels in mixed glia, which can lead to reduced lysosomal function. Overall, continuous high glucose reduces microglial and astrocytic ATP production and lysosome activity which may lead to decreased glial oAβ degradation. Our study reveals diabetes-induced hyperglycemia hinders glial oAβ clearance and contributes to oAβ accumulation in AD pathogenesis.
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Affiliation(s)
- Yung-Cheng Huang
- Department of Physical Medicine and Rehabilitation, Cheng-Hsin General Hospital, Taipei, Taiwan, Republic of China
- National Taipei University of Nursing and Health Sciences, Taipei City, Taiwan, R.O.C
| | - Shu-Meng Hsu
- Institute of Neuroscience, School of Life Science, National Yang Ming Chiao Tung University, Taipei, Taiwan, R.O.C
| | - Feng-Shiun Shie
- Center for Neuropsychiatric Research National Health Research Institutes, Zhunan Town, Miaoli County, Taiwan, R.O.C
| | - Young-Ji Shiao
- National Research Institute of Chinese Medicine, Ministry of Health and Welfare, Taipei, Taiwan
- Ph.D. Program in Clinical Drug Development of Chinese Herbal Medicine, Taipei Medical University, Taipei, Taiwan, R.O.C
- Institute of Biopharmaceutical Science, National Yang Ming Chiao Tung University, Taipei, Taiwan, R.O.C
| | - Li-Jung Chao
- Institute of Neuroscience, School of Life Science, National Yang Ming Chiao Tung University, Taipei, Taiwan, R.O.C
| | - Hui-Wen Chen
- Institute of Neuroscience, School of Life Science, National Yang Ming Chiao Tung University, Taipei, Taiwan, R.O.C
| | - Heng-Hsiang Yao
- Institute of Neuroscience, School of Life Science, National Yang Ming Chiao Tung University, Taipei, Taiwan, R.O.C
| | - Meng An Chien
- Institute of Neuroscience, School of Life Science, National Yang Ming Chiao Tung University, Taipei, Taiwan, R.O.C
| | - Chung-Chih Lin
- Department of Life Sciences and Institute of Genome Sciences, National Yang Ming Chiao Tung University, Taipei, Taiwan, Republic of China
- Brain Research Center, National Yang Ming Chiao Tung University, Taipei, Taiwan, Republic of China
- Biophotonics Interdisciplinary Research Center, National Yang Ming Chiao Tung University, Taipei, Taiwan, Republic of China
- * E-mail: (CCL); (HJT)
| | - Huey-Jen Tsay
- Institute of Neuroscience, School of Life Science, National Yang Ming Chiao Tung University, Taipei, Taiwan, R.O.C
- Brain Research Center, National Yang Ming Chiao Tung University, Taipei, Taiwan, Republic of China
- * E-mail: (CCL); (HJT)
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29
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López-Soldado I, Guinovart JJ, Duran J. Hepatic overexpression of protein targeting to glycogen attenuates obesity and improves hyperglycemia in db/db mice. Front Endocrinol (Lausanne) 2022; 13:969924. [PMID: 36157460 PMCID: PMC9500150 DOI: 10.3389/fendo.2022.969924] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/15/2022] [Accepted: 08/16/2022] [Indexed: 11/13/2022] Open
Abstract
Increased liver glycogen content has been shown to reduce food intake, attenuate obesity, and improve glucose tolerance in a mouse model of high-fat diet (HFD)-induced obesity. Here we studied the contribution of liver glycogen to the regulation of obesity and glucose metabolism in a model of type 2 diabetes and obesity, namely the db/db mouse. To this end, we crossed db/db mice with animals overexpressing protein targeting to glycogen (PTG) in the liver to generate db/db mice with increased liver glycogen content (db/db-PTG). Hepatic PTG overexpression reduced food intake and fat weight and attenuated obesity and hyperglycemia in db/db mice. Db/db-PTG mice showed similar energy expenditure and physical activity to db/db mice. PTG overexpression reduced liver phosphoenolpyruvate carboxykinase (PEPCK) protein levels and repressed hepatic glucose production in db/db mice. Moreover, increased liver glycogen elevated hepatic ATP content in these animals. However, lipid metabolism was not modified by PTG overexpression. In conclusion, increased liver glycogen content ameliorates the diabetic and obesity phenotype in db/db mice.
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Affiliation(s)
- Iliana López-Soldado
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Barcelona, Spain
- Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), Madrid, Spain
- Department of Biochemistry and Molecular Biomedicine, University of Barcelona, Barcelona, Spain
- *Correspondence: Iliana López-Soldado,
| | - Joan J. Guinovart
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Barcelona, Spain
- Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), Madrid, Spain
- Department of Biochemistry and Molecular Biomedicine, University of Barcelona, Barcelona, Spain
| | - Jordi Duran
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Barcelona, Spain
- Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), Madrid, Spain
- Institut Químic de Sarrià (IQS), Universitat Ramon Llull (URL), Barcelona, Spain
- Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute of Science and Technology, Barcelona, Spain
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30
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Krako Jakovljevic N, Pavlovic K, Zujovic T, Kravic-Stevovic T, Jotic A, Markovic I, Lalic NM. In vitro models of insulin resistance: Mitochondrial coupling is differently affected in liver and muscle cells. Mitochondrion 2021; 61:165-173. [PMID: 34634496 DOI: 10.1016/j.mito.2021.10.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Revised: 09/17/2021] [Accepted: 10/06/2021] [Indexed: 01/07/2023]
Abstract
Mitochondrial dysfunction in diabetes is a widely studied topic, but inconsistency in literature data suggests a need for valid and reproducible models that will help to clarify this interaction. We aimed to establish insulin resistance models using chronic high insulin treatment in two cell types: myocytes and hepatocytes, characterise them in terms of mitochondrial function and compare them to the widely used palmitate-induced model of insulin resistance. We found that insulin lowered phosphorylation of Akt while not affecting cell viability, ROS production, mitochondrial morphology or respiration, and caused decrease in mitochondrial coupling only in muscle but not in liver cells.
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Affiliation(s)
- Nina Krako Jakovljevic
- Clinic for Endocrinology, Diabetes and Metabolic Diseases, University Clinical Centre of Serbia, Faculty of Medicine, University of Belgrade, Dr Subotica 13, 11000 Belgrade, Serbia
| | - Kasja Pavlovic
- Clinic for Endocrinology, Diabetes and Metabolic Diseases, University Clinical Centre of Serbia, Faculty of Medicine, University of Belgrade, Dr Subotica 13, 11000 Belgrade, Serbia
| | - Tijana Zujovic
- Clinic for Endocrinology, Diabetes and Metabolic Diseases, University Clinical Centre of Serbia, Faculty of Medicine, University of Belgrade, Dr Subotica 13, 11000 Belgrade, Serbia
| | - Tamara Kravic-Stevovic
- Institute of Histology and Embryology, Faculty of Medicine, University of Belgrade, Visegradska 26, 11000 Belgrade, Serbia
| | - Aleksandra Jotic
- Clinic for Endocrinology, Diabetes and Metabolic Diseases, University Clinical Centre of Serbia, Faculty of Medicine, University of Belgrade, Dr Subotica 13, 11000 Belgrade, Serbia
| | - Ivanka Markovic
- Institute of Medical and Clinical Biochemistry, Faculty of Medicine, University of Belgrade, Pasterova 2, 11000 Belgrade, Serbia
| | - Nebojsa M Lalic
- Clinic for Endocrinology, Diabetes and Metabolic Diseases, University Clinical Centre of Serbia, Faculty of Medicine, University of Belgrade, Dr Subotica 13, 11000 Belgrade, Serbia.
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Tsilingiris D, Tzeravini E, Koliaki C, Dalamaga M, Kokkinos A. The Role of Mitochondrial Adaptation and Metabolic Flexibility in the Pathophysiology of Obesity and Insulin Resistance: an Updated Overview. Curr Obes Rep 2021; 10:191-213. [PMID: 33840072 DOI: 10.1007/s13679-021-00434-0] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 03/30/2021] [Indexed: 12/27/2022]
Abstract
PURPOSE OF REVIEW The term "metabolic flexibility" denotes the dynamic responses of the cellular oxidative machinery in order to adapt to changes in energy substrate availability. A progressive loss of this adaptive capacity has been implicated in the development of obesity-related comorbidities. Mitochondria are dynamic intracellular organelles which play a fundamental role in energy metabolism, and the mitochondrial adaptation to environmental challenges may be viewed as the functional component of metabolic flexibility. Herein, we attempt to comprehensively review the available evidence regarding the role of mitochondrial adaptation and metabolic flexibility in the pathogenesis of obesity and related morbidities, namely insulin resistance states and non-alcoholic fatty liver disease (NAFLD). RECENT FINDINGS Overall, there is a concrete body of evidence to support the presence of impaired mitochondrial adaptation as a principal component of systemic metabolic inflexibility in conditions related to obesity. There are still many unresolved questions regarding the relationship between the gradual loss of mitochondrial adaptability and the progression of obesity-related complications, such as causality issues, the timely appearance and reversibility of the described disturbances, and the generalizability of the findings to the mitochondrial content of every affected tissue or organ. The evidence regarding the causality between the observed associations remains inconclusive, although most of the available data points towards a bidirectional, potentially mutually amplifying relationship. The spectrum of NAFLD is of particular interest, since functional and pathological changes in the course of its development closely mirror the progression of dysmetabolism, if not constituting a dynamic component of the latter.
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Affiliation(s)
- Dimitrios Tsilingiris
- First Department of Propaedeutic Internal Medicine, School of Medicine, Laiko General Hospital, National and Kapodistrian University of Athens, Athens, Greece.
- Department of Internal Medicine I and Clinical Chemistry, University of Heidelberg, Heidelberg, Germany.
| | - Evangelia Tzeravini
- First Department of Propaedeutic Internal Medicine, School of Medicine, Laiko General Hospital, National and Kapodistrian University of Athens, Athens, Greece
| | - Chrysi Koliaki
- First Department of Propaedeutic Internal Medicine, School of Medicine, Laiko General Hospital, National and Kapodistrian University of Athens, Athens, Greece
| | - Maria Dalamaga
- Department of Biological Chemistry, School of Medicine, National and Kapodistrian University of Athens, Mikras Asias 75, 11527, Athens, Greece
| | - Alexander Kokkinos
- First Department of Propaedeutic Internal Medicine, School of Medicine, Laiko General Hospital, National and Kapodistrian University of Athens, Athens, Greece
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Guerra JVS, Dias MMG, Brilhante AJVC, Terra MF, García-Arévalo M, Figueira ACM. Multifactorial Basis and Therapeutic Strategies in Metabolism-Related Diseases. Nutrients 2021; 13:nu13082830. [PMID: 34444990 PMCID: PMC8398524 DOI: 10.3390/nu13082830] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2021] [Revised: 08/09/2021] [Accepted: 08/11/2021] [Indexed: 12/11/2022] Open
Abstract
Throughout the 20th and 21st centuries, the incidence of non-communicable diseases (NCDs), also known as chronic diseases, has been increasing worldwide. Changes in dietary and physical activity patterns, along with genetic conditions, are the main factors that modulate the metabolism of individuals, leading to the development of NCDs. Obesity, diabetes, metabolic associated fatty liver disease (MAFLD), and cardiovascular diseases (CVDs) are classified in this group of chronic diseases. Therefore, understanding the underlying molecular mechanisms of these diseases leads us to develop more accurate and effective treatments to reduce or mitigate their prevalence in the population. Given the global relevance of NCDs and ongoing research progress, this article reviews the current understanding about NCDs and their related risk factors, with a focus on obesity, diabetes, MAFLD, and CVDs, summarizing the knowledge about their pathophysiology and highlighting the currently available and emerging therapeutic strategies, especially pharmacological interventions. All of these diseases play an important role in the contamination by the SARS-CoV-2 virus, as well as in the progression and severity of the symptoms of the coronavirus disease 2019 (COVID-19). Therefore, we briefly explore the relationship between NCDs and COVID-19.
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Affiliation(s)
- João V. S. Guerra
- Brazilian Center for Research in Energy and Materials (CNPEM), Brazilian Biosciences National Laboratory (LNBio), Polo II de Alta Tecnologia—R. Giuseppe Máximo Scolfaro, Campinas 13083-100, Brazil; (J.V.S.G.); (M.M.G.D.); (M.F.T.)
- Graduate Program in Pharmaceutical Sciences, Faculty Pharmaceutical Sciences, University of Campinas, Campinas 13083-970, Brazil
| | - Marieli M. G. Dias
- Brazilian Center for Research in Energy and Materials (CNPEM), Brazilian Biosciences National Laboratory (LNBio), Polo II de Alta Tecnologia—R. Giuseppe Máximo Scolfaro, Campinas 13083-100, Brazil; (J.V.S.G.); (M.M.G.D.); (M.F.T.)
- Graduate Program in Functional and Molecular Biology, Institute of Biology, State University of Campinas (Unicamp), Campinas 13083-970, Brazil;
| | - Anna J. V. C. Brilhante
- Graduate Program in Functional and Molecular Biology, Institute of Biology, State University of Campinas (Unicamp), Campinas 13083-970, Brazil;
- Brazilian Center for Research in Energy and Materials (CNPEM), Brazilian Biorenewables National Laboratory (LNBR), Polo II de Alta Tecnologia—R. Giuseppe Máximo Scolfaro, Campinas 13083-100, Brazil
| | - Maiara F. Terra
- Brazilian Center for Research in Energy and Materials (CNPEM), Brazilian Biosciences National Laboratory (LNBio), Polo II de Alta Tecnologia—R. Giuseppe Máximo Scolfaro, Campinas 13083-100, Brazil; (J.V.S.G.); (M.M.G.D.); (M.F.T.)
- Graduate Program in Functional and Molecular Biology, Institute of Biology, State University of Campinas (Unicamp), Campinas 13083-970, Brazil;
| | - Marta García-Arévalo
- Brazilian Center for Research in Energy and Materials (CNPEM), Brazilian Biosciences National Laboratory (LNBio), Polo II de Alta Tecnologia—R. Giuseppe Máximo Scolfaro, Campinas 13083-100, Brazil; (J.V.S.G.); (M.M.G.D.); (M.F.T.)
- Correspondence: or (M.G.-A.); (A.C.M.F.)
| | - Ana Carolina M. Figueira
- Brazilian Center for Research in Energy and Materials (CNPEM), Brazilian Biosciences National Laboratory (LNBio), Polo II de Alta Tecnologia—R. Giuseppe Máximo Scolfaro, Campinas 13083-100, Brazil; (J.V.S.G.); (M.M.G.D.); (M.F.T.)
- Correspondence: or (M.G.-A.); (A.C.M.F.)
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Pafili K, Roden M. Nonalcoholic fatty liver disease (NAFLD) from pathogenesis to treatment concepts in humans. Mol Metab 2021; 50:101122. [PMID: 33220492 PMCID: PMC8324683 DOI: 10.1016/j.molmet.2020.101122] [Citation(s) in RCA: 144] [Impact Index Per Article: 48.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Revised: 10/30/2020] [Accepted: 11/13/2020] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Nonalcoholic fatty liver disease (NAFLD) comprises hepatic alterations with increased lipid accumulation (steatosis) without or with inflammation (nonalcoholic steatohepatitis, NASH) and/or fibrosis in the absence of other causes of liver disease. NAFLD is developing as a burgeoning health challenge, mainly due to the worldwide obesity and diabetes epidemics. SCOPE OF REVIEW This review summarizes the knowledge on the pathogenesis underlying NAFLD by focusing on studies in humans and on hypercaloric nutrition, including effects of saturated fat and fructose, as well as adipose tissue dysfunction, leading to hepatic lipotoxicity, abnormal mitochondrial function, and oxidative stress, and highlights intestinal dysbiosis. These mechanisms are discussed in the context of current treatments targeting metabolic pathways and the results of related clinical trials. MAJOR CONCLUSIONS Recent studies have provided evidence that certain conditions, for example, the severe insulin-resistant diabetes (SIRD) subgroup (cluster) and the presence of an increasing number of gene variants, seem to predispose for excessive risk of NAFLD and its accelerated progression. Recent clinical trials have been frequently unsuccessful in halting or preventing NAFLD progression, perhaps partly due to including unselected cohorts in later stages of NAFLD. On the basis of this literature review, this study proposed screening in individuals with the highest genetic or acquired risk of disease progression, for example, the SIRD subgroup, and developing treatment concepts targeting the earliest pathophysiolgical alterations, namely, adipocyte dysfunction and insulin resistance.
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Affiliation(s)
- Kalliopi Pafili
- Institute of Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research, Düsseldorf, Germany; German Center for Diabetes Research, München-Neuherberg, Germany
| | - Michael Roden
- Institute of Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research, Düsseldorf, Germany; German Center for Diabetes Research, München-Neuherberg, Germany; Division of Endocrinology and Diabetology, Medical Faculty, Heinrich-Heine University, Düsseldorf, Germany.
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von Loeffelholz C, Coldewey SM, Birkenfeld AL. A Narrative Review on the Role of AMPK on De Novo Lipogenesis in Non-Alcoholic Fatty Liver Disease: Evidence from Human Studies. Cells 2021; 10:cells10071822. [PMID: 34359991 PMCID: PMC8306246 DOI: 10.3390/cells10071822] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2021] [Revised: 07/01/2021] [Accepted: 07/15/2021] [Indexed: 02/06/2023] Open
Abstract
5′AMP-activated protein kinase (AMPK) is known as metabolic sensor in mammalian cells that becomes activated by an increasing adenosine monophosphate (AMP)/adenosine triphosphate (ATP) ratio. The heterotrimeric AMPK protein comprises three subunits, each of which has multiple phosphorylation sites, playing an important role in the regulation of essential molecular pathways. By phosphorylation of downstream proteins and modulation of gene transcription AMPK functions as a master switch of energy homeostasis in tissues with high metabolic turnover, such as the liver, skeletal muscle, and adipose tissue. Regulation of AMPK under conditions of chronic caloric oversupply emerged as substantial research target to get deeper insight into the pathogenesis of non-alcoholic fatty liver disease (NAFLD). Evidence supporting the role of AMPK in NAFLD is mainly derived from preclinical cell culture and animal studies. Dysbalanced de novo lipogenesis has been identified as one of the key processes in NAFLD pathogenesis. Thus, the scope of this review is to provide an integrative overview of evidence, in particular from clinical studies and human samples, on the role of AMPK in the regulation of primarily de novo lipogenesis in human NAFLD.
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Affiliation(s)
- Christian von Loeffelholz
- Department of Anesthesiology and Intensive Care Medicine, Jena University Hospital, 07747 Jena, Germany;
- Correspondence: ; Tel.: +49-3641-9323-177; Fax: +49-3641-9323-102
| | - Sina M. Coldewey
- Department of Anesthesiology and Intensive Care Medicine, Jena University Hospital, 07747 Jena, Germany;
- Septomics Research Center, Jena University Hospital, 07747 Jena, Germany
- Center for Sepsis Control and Care, Jena University Hospital, 07747 Jena, Germany
| | - Andreas L. Birkenfeld
- Department of Diabetology Endocrinology and Nephrology, University Hospital Tübingen, Eberhard Karls University Tübingen, 72074 Tübingen, Germany;
- Department of Therapy of Diabetes, Institute of Diabetes Research and Metabolic Diseases in the Helmholtz Center Munich, Eberhard Karls University Tübingen, 72074 Tübingen, Germany
- Division of Diabetes and Nutritional Sciences, Rayne Institute, King’s College London, London SE5 9RJ, UK
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Di Ciaula A, Calamita G, Shanmugam H, Khalil M, Bonfrate L, Wang DQH, Baffy G, Portincasa P. Mitochondria Matter: Systemic Aspects of Nonalcoholic Fatty Liver Disease (NAFLD) and Diagnostic Assessment of Liver Function by Stable Isotope Dynamic Breath Tests. Int J Mol Sci 2021; 22:7702. [PMID: 34299321 PMCID: PMC8305940 DOI: 10.3390/ijms22147702] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2021] [Revised: 07/08/2021] [Accepted: 07/14/2021] [Indexed: 02/07/2023] Open
Abstract
The liver plays a key role in systemic metabolic processes, which include detoxification, synthesis, storage, and export of carbohydrates, lipids, and proteins. The raising trends of obesity and metabolic disorders worldwide is often associated with the nonalcoholic fatty liver disease (NAFLD), which has become the most frequent type of chronic liver disorder with risk of progression to cirrhosis and hepatocellular carcinoma. Liver mitochondria play a key role in degrading the pathways of carbohydrates, proteins, lipids, and xenobiotics, and to provide energy for the body cells. The morphological and functional integrity of mitochondria guarantee the proper functioning of β-oxidation of free fatty acids and of the tricarboxylic acid cycle. Evaluation of the liver in clinical medicine needs to be accurate in NAFLD patients and includes history, physical exam, imaging, and laboratory assays. Evaluation of mitochondrial function in chronic liver disease and NAFLD is now possible by novel diagnostic tools. "Dynamic" liver function tests include the breath test (BT) based on the use of substrates marked with the non-radioactive, naturally occurring stable isotope 13C. Hepatocellular metabolization of the substrate will generate 13CO2, which is excreted in breath and measured by mass spectrometry or infrared spectroscopy. Breath levels of 13CO2 are biomarkers of specific metabolic processes occurring in the hepatocyte cytosol, microsomes, and mitochondria. 13C-BTs explore distinct chronic liver diseases including simple liver steatosis, non-alcoholic steatohepatitis, liver fibrosis, cirrhosis, hepatocellular carcinoma, drug, and alcohol effects. In NAFLD, 13C-BT use substrates such as α-ketoisocaproic acid, methionine, and octanoic acid to assess mitochondrial oxidation capacity which can be impaired at an early stage of disease. 13C-BTs represent an indirect, cost-effective, and easy method to evaluate dynamic liver function. Further applications are expected in clinical medicine. In this review, we discuss the involvement of liver mitochondria in the progression of NAFLD, together with the role of 13C-BT in assessing mitochondrial function and its potential use in the prevention and management of NAFLD.
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Affiliation(s)
- Agostino Di Ciaula
- Clinica Medica “A. Murri”, Department of Biomedical Sciences & Human Oncology, University of Bari Medical School, 70124 Bari, Italy; (A.D.C.); (H.S.); (M.K.); (L.B.)
| | - Giuseppe Calamita
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari “Aldo Moro”, 70100 Bari, Italy;
| | - Harshitha Shanmugam
- Clinica Medica “A. Murri”, Department of Biomedical Sciences & Human Oncology, University of Bari Medical School, 70124 Bari, Italy; (A.D.C.); (H.S.); (M.K.); (L.B.)
| | - Mohamad Khalil
- Clinica Medica “A. Murri”, Department of Biomedical Sciences & Human Oncology, University of Bari Medical School, 70124 Bari, Italy; (A.D.C.); (H.S.); (M.K.); (L.B.)
| | - Leonilde Bonfrate
- Clinica Medica “A. Murri”, Department of Biomedical Sciences & Human Oncology, University of Bari Medical School, 70124 Bari, Italy; (A.D.C.); (H.S.); (M.K.); (L.B.)
| | - David Q.-H. Wang
- Marion Bessin Liver Research Center, Einstein-Mount Sinai Diabetes Research Center, Department of Medicine and Genetics, Division of Gastroenterology and Liver Diseases, Albert Einstein College of Medicine, Bronx, NY 10461, USA;
| | - Gyorgy Baffy
- Department of Medicine, VA Boston Healthcare System and Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02130, USA;
| | - Piero Portincasa
- Clinica Medica “A. Murri”, Department of Biomedical Sciences & Human Oncology, University of Bari Medical School, 70124 Bari, Italy; (A.D.C.); (H.S.); (M.K.); (L.B.)
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36
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Geisler CE, Ghimire S, Hepler C, Miller KE, Bruggink SM, Kentch KP, Higgins MR, Banek CT, Yoshino J, Klein S, Renquist BJ. Hepatocyte membrane potential regulates serum insulin and insulin sensitivity by altering hepatic GABA release. Cell Rep 2021; 35:109298. [PMID: 34192533 PMCID: PMC8341405 DOI: 10.1016/j.celrep.2021.109298] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2020] [Revised: 04/17/2021] [Accepted: 06/03/2021] [Indexed: 01/10/2023] Open
Abstract
Hepatic lipid accumulation in obesity correlates with the severity of hyperinsulinemia and systemic insulin resistance. Obesity-induced hepatocellular lipid accumulation results in hepatocyte depolarization. We have established that hepatocyte depolarization depresses hepatic afferent vagal nerve firing, increases GABA release from liver slices, and causes hyperinsulinemia. Preventing hepatic GABA release or eliminating the ability of the liver to communicate to the hepatic vagal nerve ameliorates the hyperinsulinemia and insulin resistance associated with diet-induced obesity. In people with obesity, hepatic expression of GABA transporters is associated with glucose infusion and disposal rates during a hyperinsulinemic euglycemic clamp. Single-nucleotide polymorphisms in hepatic GABA re-uptake transporters are associated with an increased incidence of type 2 diabetes mellitus. Herein, we identify GABA as a neuro-hepatokine that is dysregulated in obesity and whose release can be manipulated to mute or exacerbate the glucoregulatory dysfunction common to obesity.
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Affiliation(s)
- Caroline E Geisler
- School of Animal and Comparative Biomedical Sciences, University of Arizona, Tucson, AZ 85721, USA; Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Susma Ghimire
- School of Animal and Comparative Biomedical Sciences, University of Arizona, Tucson, AZ 85721, USA
| | - Chelsea Hepler
- School of Animal and Comparative Biomedical Sciences, University of Arizona, Tucson, AZ 85721, USA; Robert H. Lurie Medical Research Center, Northwestern University, Chicago, IL 60611, USA
| | - Kendra E Miller
- School of Animal and Comparative Biomedical Sciences, University of Arizona, Tucson, AZ 85721, USA
| | - Stephanie M Bruggink
- School of Animal and Comparative Biomedical Sciences, University of Arizona, Tucson, AZ 85721, USA
| | - Kyle P Kentch
- School of Animal and Comparative Biomedical Sciences, University of Arizona, Tucson, AZ 85721, USA
| | - Mark R Higgins
- School of Animal and Comparative Biomedical Sciences, University of Arizona, Tucson, AZ 85721, USA
| | | | - Jun Yoshino
- Center for Human Nutrition, Washington University School of Medicine, St. Louis, MO, USA
| | - Samuel Klein
- Center for Human Nutrition, Washington University School of Medicine, St. Louis, MO, USA
| | - Benjamin J Renquist
- School of Animal and Comparative Biomedical Sciences, University of Arizona, Tucson, AZ 85721, USA.
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37
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Krako Jakovljevic N, Pavlovic K, Jotic A, Lalic K, Stoiljkovic M, Lukic L, Milicic T, Macesic M, Stanarcic Gajovic J, Lalic NM. Targeting Mitochondria in Diabetes. Int J Mol Sci 2021; 22:6642. [PMID: 34205752 PMCID: PMC8233932 DOI: 10.3390/ijms22126642] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Revised: 06/14/2021] [Accepted: 06/15/2021] [Indexed: 12/18/2022] Open
Abstract
Type 2 diabetes (T2D), one of the most prevalent noncommunicable diseases, is often preceded by insulin resistance (IR), which underlies the inability of tissues to respond to insulin and leads to disturbed metabolic homeostasis. Mitochondria, as a central player in the cellular energy metabolism, are involved in the mechanisms of IR and T2D. Mitochondrial function is affected by insulin resistance in different tissues, among which skeletal muscle and liver have the highest impact on whole-body glucose homeostasis. This review focuses on human studies that assess mitochondrial function in liver, muscle and blood cells in the context of T2D. Furthermore, different interventions targeting mitochondria in IR and T2D are listed, with a selection of studies using respirometry as a measure of mitochondrial function, for better data comparison. Altogether, mitochondrial respiratory capacity appears to be a metabolic indicator since it decreases as the disease progresses but increases after lifestyle (exercise) and pharmacological interventions, together with the improvement in metabolic health. Finally, novel therapeutics developed to target mitochondria have potential for a more integrative therapeutic approach, treating both causative and secondary defects of diabetes.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | - Nebojsa M. Lalic
- Clinic for Endocrinology, Diabetes and Metabolic Diseases, University Clinical Center of Serbia, Faculty of Medicine, University of Belgrade, Dr Subotica 13, 11000 Belgrade, Serbia; (N.K.J.); (K.P.); (A.J.); (K.L.); (M.S.); (L.L.); (T.M.); (M.M.); (J.S.G.)
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38
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Schröder B, Kahl S, Roden M. Non-alcoholic fatty liver disease in type 2 diabetes - A specific entity? Liver Int 2021; 41 Suppl 1:105-111. [PMID: 34155798 DOI: 10.1111/liv.14846] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Accepted: 02/22/2021] [Indexed: 01/03/2023]
Abstract
Individuals with obesity or type 2 diabetes (T2D) have an increased risk of developing non-alcoholic fatty liver disease (NAFLD). In insulin-resistant states, altered adipose tissue function may be the initial abnormality underlying NAFLD. Hepatic lipid oversupply interferes with insulin signalling and mitochondrial function. In obese individuals, adaptation of hepatic mitochondrial respiration fails with the progression of NAFLD and can activate pro-inflammatory pathways. T2D as well as type 1 diabetes are associated with altered hepatic mitochondrial function. Screening for NAFLD remains challenging especially in those with diabetes because liver enzymes are often in the normal range and the performance of NAFLD scores is limited. Patients with T2D and severe insulin-resistant diabetes (SIRD) have the highest prevalence of NAFLD at diagnosis and the greatest risk of progression. In this subgroup, the single-nucleotide-polymorphism (SNP) rs738409(G) of the patatin-like phospholipase domain-containing protein 3 (PNPLA3) gene is associated with high liver fat content and adipose tissue insulin resistance. This frequent SNP is also known to be associated with lean NAFLD so that genetic testing for this and other SNPs could improve future screening strategies to identify high-risk individuals. Although lifestyle modifications are effective, this approach is limited owing to difficulties with compliance and several classes of drugs are being tested to treat NAFLD. Antihyperglycaemic drugs such as glucagon-like peptide 1 receptor agonists (GLP-1 RA), sodium-glucose cotransporter 2 inhibitors (SGLT2i) and pioglitazone are promising and halt the progression of NAFLD. In conclusion, although NAFLD in diabetes may not be a separate entity, there are specific features to its pathogenesis and clinical management.
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Affiliation(s)
- Benjamin Schröder
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research at Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany.,German Center for Diabetes Research, Partner Düsseldorf, München-Neuherberg, Germany
| | - Sabine Kahl
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research at Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany.,German Center for Diabetes Research, Partner Düsseldorf, München-Neuherberg, Germany
| | - Michael Roden
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research at Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany.,German Center for Diabetes Research, Partner Düsseldorf, München-Neuherberg, Germany.,Department of Endocrinology and Diabetology, Medical Faculty and University Hospital Düsseldorf, Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany
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39
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Cao K, Lv W, Wang X, Dong S, Liu X, Yang T, Xu J, Zeng M, Zou X, Zhao D, Ma Q, Lin M, Long J, Zang W, Gao F, Feng Z, Liu J. Hypermethylation of Hepatic Mitochondrial ND6 Provokes Systemic Insulin Resistance. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2021; 8:2004507. [PMID: 34141522 PMCID: PMC8188198 DOI: 10.1002/advs.202004507] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/23/2020] [Revised: 03/18/2021] [Indexed: 05/10/2023]
Abstract
Mitochondrial epigenetics is rising as intriguing notion for its potential involvement in aging and diseases, while the details remain largely unexplored. Here it is shown that among the 13 mitochondrial DNA (mtDNA) encoded genes, NADH-dehydrogenase 6 (ND6) transcript is primarily decreased in obese and type 2 diabetes populations, which negatively correlates with its distinctive hypermethylation. Hepatic mtDNA sequencing in mice unveils that ND6 presents the highest methylation level, which dramatically increases under diabetic condition due to enhanced mitochondrial translocation of DNA methyltransferase 1 (DNMT1) promoted by free fatty acid through adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK) activation. Hepatic knockdown of ND6 or overexpression of Dnmt1 similarly impairs mitochondrial function and induces systemic insulin resistance both in vivo and in vitro. Genetic or chemical targeting hepatic DNMT1 shows significant benefits against insulin resistance associated metabolic disorders. These findings highlight the pivotal role of ND6 epigenetic network in regulating mitochondrial function and onset of insulin resistance, shedding light on potential preventive and therapeutic strategies of insulin resistance and related metabolic disorders from a perspective of mitochondrial epigenetics.
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Affiliation(s)
- Ke Cao
- Center for Mitochondrial Biology and MedicineThe Key Laboratory of Biomedical Information Engineering of Ministry of EducationSchool of Life Science and TechnologyXi'an Jiaotong UniversityXi'anShaanxi710049China
| | - Weiqiang Lv
- Center for Mitochondrial Biology and MedicineThe Key Laboratory of Biomedical Information Engineering of Ministry of EducationSchool of Life Science and TechnologyXi'an Jiaotong UniversityXi'anShaanxi710049China
| | - Xueqiang Wang
- Center for Mitochondrial Biology and MedicineThe Key Laboratory of Biomedical Information Engineering of Ministry of EducationSchool of Life Science and TechnologyXi'an Jiaotong UniversityXi'anShaanxi710049China
| | - Shanshan Dong
- Biomedical Informatics & Genomics CenterThe Key Laboratory of Biomedical Information Engineering of Ministry of EducationSchool of Life Science and TechnologyXi'an Jiaotong UniversityXi'anShannxi710049China
| | - Xuyun Liu
- Center for Mitochondrial Biology and MedicineThe Key Laboratory of Biomedical Information Engineering of Ministry of EducationSchool of Life Science and TechnologyXi'an Jiaotong UniversityXi'anShaanxi710049China
| | - Tielin Yang
- Biomedical Informatics & Genomics CenterThe Key Laboratory of Biomedical Information Engineering of Ministry of EducationSchool of Life Science and TechnologyXi'an Jiaotong UniversityXi'anShannxi710049China
| | - Jie Xu
- Center for Mitochondrial Biology and MedicineThe Key Laboratory of Biomedical Information Engineering of Ministry of EducationSchool of Life Science and TechnologyXi'an Jiaotong UniversityXi'anShaanxi710049China
| | - Mengqi Zeng
- Center for Mitochondrial Biology and MedicineThe Key Laboratory of Biomedical Information Engineering of Ministry of EducationSchool of Life Science and TechnologyXi'an Jiaotong UniversityXi'anShaanxi710049China
| | - Xuan Zou
- National & Local Joint Engineering Research Center of Biodiagnosis and BiotherapyThe Second Affiliated Hospital of Xi'an Jiaotong UniversityXi'anShannxi710004China
| | - Daina Zhao
- Center for Mitochondrial Biology and MedicineThe Key Laboratory of Biomedical Information Engineering of Ministry of EducationSchool of Life Science and TechnologyXi'an Jiaotong UniversityXi'anShaanxi710049China
| | - Qingqing Ma
- Guizhou Aerospace HospitalZunyiGuizhou563099China
| | - Mu Lin
- Guizhou Aerospace HospitalZunyiGuizhou563099China
| | - Jiangang Long
- Center for Mitochondrial Biology and MedicineThe Key Laboratory of Biomedical Information Engineering of Ministry of EducationSchool of Life Science and TechnologyXi'an Jiaotong UniversityXi'anShaanxi710049China
| | - Weijin Zang
- Department of PharmacologySchool of Basic Medical SciencesXi'an Jiaotong University Health Science CenterXi'anShaanxi710061China
| | - Feng Gao
- School of Aerospace MedicineFourth Military Medical UniversityXi'an710032China
| | - Zhihui Feng
- Center for Mitochondrial Biology and MedicineThe Key Laboratory of Biomedical Information Engineering of Ministry of EducationSchool of Life Science and TechnologyXi'an Jiaotong UniversityXi'anShaanxi710049China
- Frontier Institute of Science and TechnologyXi'an Jiaotong UniversityXi'anShaanxi710049China
| | - Jiankang Liu
- Center for Mitochondrial Biology and MedicineThe Key Laboratory of Biomedical Information Engineering of Ministry of EducationSchool of Life Science and TechnologyXi'an Jiaotong UniversityXi'anShaanxi710049China
- Frontier Institute of Science and TechnologyXi'an Jiaotong UniversityXi'anShaanxi710049China
- National & Local Joint Engineering Research Center of Biodiagnosis and BiotherapyThe Second Affiliated Hospital of Xi'an Jiaotong UniversityXi'anShannxi710004China
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Di Ciaula A, Passarella S, Shanmugam H, Noviello M, Bonfrate L, Wang DQH, Portincasa P. Nonalcoholic Fatty Liver Disease (NAFLD). Mitochondria as Players and Targets of Therapies? Int J Mol Sci 2021; 22:ijms22105375. [PMID: 34065331 PMCID: PMC8160908 DOI: 10.3390/ijms22105375] [Citation(s) in RCA: 65] [Impact Index Per Article: 21.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2021] [Revised: 05/14/2021] [Accepted: 05/18/2021] [Indexed: 12/12/2022] Open
Abstract
Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disease and represents the hepatic expression of several metabolic abnormalities of high epidemiologic relevance. Fat accumulation in the hepatocytes results in cellular fragility and risk of progression toward necroinflammation, i.e., nonalcoholic steatohepatitis (NASH), fibrosis, cirrhosis, and eventually hepatocellular carcinoma. Several pathways contribute to fat accumulation and damage in the liver and can also involve the mitochondria, whose functional integrity is essential to maintain liver bioenergetics. In NAFLD/NASH, both structural and functional mitochondrial abnormalities occur and can involve mitochondrial electron transport chain, decreased mitochondrial β-oxidation of free fatty acids, excessive generation of reactive oxygen species, and lipid peroxidation. NASH is a major target of therapy, but there is no established single or combined treatment so far. Notably, translational and clinical studies point to mitochondria as future therapeutic targets in NAFLD since the prevention of mitochondrial damage could improve liver bioenergetics.
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Affiliation(s)
- Agostino Di Ciaula
- Department of Biomedical Sciences & Human Oncology, Clinica Medica “A. Murri”, University of Bari Medical School, 70124 Bari, Italy; (A.D.C.); (H.S.); (M.N.); (L.B.)
| | - Salvatore Passarella
- School of Medicine, University of Bari Medical School, 70124 Bari, Italy
- Correspondence: (S.P.); (P.P.); Tel.: +39-328-468-7215 (P.P.)
| | - Harshitha Shanmugam
- Department of Biomedical Sciences & Human Oncology, Clinica Medica “A. Murri”, University of Bari Medical School, 70124 Bari, Italy; (A.D.C.); (H.S.); (M.N.); (L.B.)
| | - Marica Noviello
- Department of Biomedical Sciences & Human Oncology, Clinica Medica “A. Murri”, University of Bari Medical School, 70124 Bari, Italy; (A.D.C.); (H.S.); (M.N.); (L.B.)
| | - Leonilde Bonfrate
- Department of Biomedical Sciences & Human Oncology, Clinica Medica “A. Murri”, University of Bari Medical School, 70124 Bari, Italy; (A.D.C.); (H.S.); (M.N.); (L.B.)
| | - David Q.-H. Wang
- Department of Medicine and Genetics, Division of Gastroenterology and Liver Diseases, Marion Bessin Liver Research Center, Einstein-Mount Sinai Diabetes Research Center, Albert Einstein College of Medicine, Bronx, NY 10461, USA;
| | - Piero Portincasa
- Department of Biomedical Sciences & Human Oncology, Clinica Medica “A. Murri”, University of Bari Medical School, 70124 Bari, Italy; (A.D.C.); (H.S.); (M.N.); (L.B.)
- Correspondence: (S.P.); (P.P.); Tel.: +39-328-468-7215 (P.P.)
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41
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López-Soldado I, Guinovart JJ, Duran J. Increasing hepatic glycogen moderates the diabetic phenotype in insulin-deficient Akita mice. J Biol Chem 2021; 296:100498. [PMID: 33667544 PMCID: PMC8027280 DOI: 10.1016/j.jbc.2021.100498] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2020] [Revised: 02/23/2021] [Accepted: 03/01/2021] [Indexed: 12/14/2022] Open
Abstract
Hepatic glycogen metabolism is impaired in diabetes. We previously demonstrated that strategies to increase liver glycogen content in a high-fat-diet mouse model of obesity and insulin resistance led to a reduction in food intake and ameliorated obesity and glucose tolerance. These effects were accompanied by a decrease in insulin levels, but whether this decrease contributed to the phenotype observed in this animal was unclear. Here we sought to evaluate this aspect directly, by examining the long-term effects of increasing liver glycogen in an animal model of insulin-deficient and monogenic diabetes, namely the Akita mouse, which is characterized by reduced insulin production. We crossed Akita mice with animals overexpressing protein targeting to glycogen (PTG) in the liver to generate Akita mice with increased liver glycogen content (Akita-PTGOE). Akita-PTGOE animals showed lower glycemia, lower food intake, and decreased water consumption and urine output compared with Akita mice. Furthermore, Akita-PTGOE mice showed a restoration of the hepatic energy state and a normalization of gluconeogenesis and glycolysis back to nondiabetic levels. Moreover, hepatic lipogenesis, which is reduced in Akita mice, was reverted in Akita-PTGOE animals. These results demonstrate that strategies to increase liver glycogen content lead to the long-term reduction of the diabetic phenotype, independently of circulating insulin.
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Affiliation(s)
- Iliana López-Soldado
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Barcelona, Spain; Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), Madrid, Spain.
| | - Joan J Guinovart
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Barcelona, Spain; Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), Madrid, Spain; Department of Biochemistry and Molecular Biomedicine, University of Barcelona, Barcelona, Spain
| | - Jordi Duran
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Barcelona, Spain; Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), Madrid, Spain
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42
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Shannon CE, Ragavan M, Palavicini JP, Fourcaudot M, Bakewell TM, Valdez IA, Ayala I, Jin ES, Madesh M, Han X, Merritt ME, Norton L. Insulin resistance is mechanistically linked to hepatic mitochondrial remodeling in non-alcoholic fatty liver disease. Mol Metab 2021; 45:101154. [PMID: 33359401 PMCID: PMC7811046 DOI: 10.1016/j.molmet.2020.101154] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Revised: 12/18/2020] [Accepted: 12/20/2020] [Indexed: 12/23/2022] Open
Abstract
OBJECTIVE Insulin resistance and altered hepatic mitochondrial function are central features of type 2 diabetes (T2D) and non-alcoholic fatty liver disease (NAFLD), but the etiological role of these processes in disease progression remains unclear. Here we investigated the molecular links between insulin resistance, mitochondrial remodeling, and hepatic lipid accumulation. METHODS Hepatic insulin sensitivity, endogenous glucose production, and mitochondrial metabolic fluxes were determined in wild-type, obese (ob/ob) and pioglitazone-treatment obese mice using a combination of radiolabeled tracer and stable isotope NMR approaches. Mechanistic studies of pioglitazone action were performed in isolated primary hepatocytes, whilst molecular hepatic lipid species were profiled using shotgun lipidomics. RESULTS Livers from obese, insulin-resistant mice displayed augmented mitochondrial content and increased tricarboxylic acid cycle (TCA) cycle and pyruvate dehydrogenase (PDH) activities. Insulin sensitization with pioglitazone mitigated pyruvate-driven TCA cycle activity and PDH activation via both allosteric (intracellular pyruvate availability) and covalent (PDK4 and PDP2) mechanisms that were dependent on PPARγ activity in isolated primary hepatocytes. Improved mitochondrial function following pioglitazone treatment was entirely dissociated from changes in hepatic triglycerides, diacylglycerides, or fatty acids. Instead, we highlight a role for the mitochondrial phospholipid cardiolipin, which underwent pathological remodeling in livers from obese mice that was reversed by insulin sensitization. CONCLUSION Our findings identify targetable mitochondrial features of T2D and NAFLD and highlight the benefit of insulin sensitization in managing the clinical burden of obesity-associated disease.
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Affiliation(s)
- Chris E Shannon
- Division of Diabetes, University of Texas Health Science Center and Texas Diabetes Institute, San Antonio, TX, USA
| | - Mukundan Ragavan
- Department of Biochemistry and Molecular Biology, College of Medicine, University of Florida, Gainesville, FL, USA
| | - Juan Pablo Palavicini
- Division of Diabetes, University of Texas Health Science Center and Texas Diabetes Institute, San Antonio, TX, USA; Barshop Institute for Longevity and Aging Studies, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - Marcel Fourcaudot
- Division of Diabetes, University of Texas Health Science Center and Texas Diabetes Institute, San Antonio, TX, USA
| | - Terry M Bakewell
- Division of Diabetes, University of Texas Health Science Center and Texas Diabetes Institute, San Antonio, TX, USA
| | - Ivan A Valdez
- Division of Diabetes, University of Texas Health Science Center and Texas Diabetes Institute, San Antonio, TX, USA
| | - Iriscilla Ayala
- Division of Diabetes, University of Texas Health Science Center and Texas Diabetes Institute, San Antonio, TX, USA
| | - Eunsook S Jin
- Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Muniswamy Madesh
- Division of Nephrology, University of Texas Health Science Center and Texas Diabetes Institute, San Antonio, TX, USA
| | - Xianlin Han
- Division of Diabetes, University of Texas Health Science Center and Texas Diabetes Institute, San Antonio, TX, USA; Barshop Institute for Longevity and Aging Studies, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA; Glenn Biggs Institute for Alzheimer's & Neurodegenerative Diseases, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - Matthew E Merritt
- Department of Biochemistry and Molecular Biology, College of Medicine, University of Florida, Gainesville, FL, USA
| | - Luke Norton
- Division of Diabetes, University of Texas Health Science Center and Texas Diabetes Institute, San Antonio, TX, USA.
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Metabolic Imaging in Non-Alcoholic Fatty Liver Disease: Applications of Magnetic Resonance Spectroscopy. J Clin Med 2021; 10:jcm10040632. [PMID: 33562284 PMCID: PMC7915174 DOI: 10.3390/jcm10040632] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2020] [Revised: 01/22/2021] [Accepted: 01/26/2021] [Indexed: 12/20/2022] Open
Abstract
Non-alcoholic fatty liver disease (NAFLD) is poised to dominate the landscape of clinical hepatology in the 21st century. Its complex, interdependent aetiologies, non-linear disease progression and uncertain natural history have presented great challenges to the development of effective therapies. Progress will require an integrated approach to uncover molecular mediators, key pathogenic milestones and response to intervention at the metabolic level. The advent of precision imaging has yielded unprecedented insights into these processes. Quantitative imaging biomarkers such as magnetic resonance imaging (MRI), spectroscopy (MRS) and elastography (MRE) present robust, powerful tools with which to probe NAFLD metabolism and fibrogenesis non-invasively, in real time. Specific advantages of MRS include the ability to quantify static metabolite concentrations as well as dynamic substrate flux in vivo. Thus, a vast range of key metabolic events in the natural history of NAFLD can be explored using MRS. Here, we provide an overview of MRS for the clinician, as well as key pathways exploitable by MRS in vivo. Development, optimisation and validation of multinuclear MRS, in combination with other quantitative imaging techniques, may ultimately provide a robust, non-invasive alternative to liver biopsy for observational and longitudinal studies. Through enabling deeper insight into inflammatory and fibrogenic cascades, MRS may facilitate identification of novel therapeutic targets and clinically meaningful endpoints in NAFLD. Its widespread use in future could conceivably accelerate study design, data acquisition and availability of disease-modifying therapies at a population level.
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Therapeutic potential of mitochondrial uncouplers for the treatment of metabolic associated fatty liver disease and NASH. Mol Metab 2021; 46:101178. [PMID: 33545391 PMCID: PMC8085597 DOI: 10.1016/j.molmet.2021.101178] [Citation(s) in RCA: 51] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Revised: 01/18/2021] [Accepted: 01/28/2021] [Indexed: 12/13/2022] Open
Abstract
Background Mitochondrial uncouplers shuttle protons across the inner mitochondrial membrane via a pathway that is independent of adenosine triphosphate (ATP) synthase, thereby uncoupling nutrient oxidation from ATP production and dissipating the proton gradient as heat. While initial toxicity concerns hindered their therapeutic development in the early 1930s, there has been increased interest in exploring the therapeutic potential of mitochondrial uncouplers for the treatment of metabolic diseases. Scope of review In this review, we cover recent advances in the mechanisms by which mitochondrial uncouplers regulate biological processes and disease, with a particular focus on metabolic associated fatty liver disease (MAFLD), nonalcoholic hepatosteatosis (NASH), insulin resistance, and type 2 diabetes (T2D). We also discuss the challenges that remain to be addressed before synthetic and natural mitochondrial uncouplers can successfully enter the clinic. Major conclusions Rodent and non-human primate studies suggest that a myriad of small molecule mitochondrial uncouplers can safely reverse MAFLD/NASH with a wide therapeutic index. Despite this, further characterization of the tissue- and cell-specific effects of mitochondrial uncouplers is needed. We propose targeting the dosing of mitochondrial uncouplers to specific tissues such as the liver and/or developing molecules with self-limiting properties to induce a subtle and sustained increase in mitochondrial inefficiency, thereby avoiding systemic toxicity concerns.
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Rothe M, Wessel C, Cames S, Szendroedi J, Burkart V, Hwang JH, Roden M. In vivo absolute quantification of hepatic γ-ATP concentration in mice using 31 P MRS at 11.7 T. NMR IN BIOMEDICINE 2021; 34:e4422. [PMID: 33025629 DOI: 10.1002/nbm.4422] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2020] [Revised: 09/14/2020] [Accepted: 09/15/2020] [Indexed: 06/11/2023]
Abstract
Measurement of ATP concentrations and synthesis in humans indicated abnormal hepatic energy metabolism in obesity, non-alcoholic fatty liver disease (NAFLD) and Type 2 diabetes. Further mechanistic studies on energy metabolism require the detailed phenotyping of specific mouse models. Thus, this study aimed to establish and evaluate a robust and fast single voxel 31 P MRS method to quantify hepatic γ-ATP concentrations at 11.7 T in three mouse models with different insulin sensitivities and liver fat contents (72-week-old C57BL/6 control mice, 72-week-old insulin resistant sterol regulatory-element binding protein-1c overexpressing (SREBP-1c+ ) mice and 10-12-week-old prediabetic non-obese diabetic (NOD) mice). Absolute quantification was performed by employing an external reference and a matching replacement ATP phantom with 3D image selected in vivo spectroscopy 31 P MRS. This single voxel 31 P MRS method non-invasively quantified hepatic γ-ATP within 17 min and the repeatability tests provided a coefficient of variation of 7.8 ± 1.1%. The mean hepatic γ-ATP concentrations were markedly lower in SREBP-1c+ mice (1.14 ± 0.10 mM) than in C57BL/6 mice (2.15 ± 0.13 mM; p < 0.0002) and NOD mice (1.78 ± 0.13 mM; p < 0.006, one-way ANOVA test). In conclusion, this method allows us to rapidly and precisely measure hepatic γ-ATP concentrations, and thereby to non-invasively detect abnormal hepatic energy metabolism in mice with different degrees of insulin resistance and NAFLD. Thus, this 31 P MRS will also be useful for future mechanistic as well as therapeutic translational studies in other murine models.
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Affiliation(s)
- Maik Rothe
- Institute for Clinical Diabetology, German Diabetes Center at Heinrich Heine University, Leibniz Institute for Diabetes Research, Düsseldorf, Germany
- German Center for Diabetes Research, München-Neuherberg, Germany
| | - Corinna Wessel
- Institute for Clinical Diabetology, German Diabetes Center at Heinrich Heine University, Leibniz Institute for Diabetes Research, Düsseldorf, Germany
- German Center for Diabetes Research, München-Neuherberg, Germany
| | - Sandra Cames
- Institute for Clinical Diabetology, German Diabetes Center at Heinrich Heine University, Leibniz Institute for Diabetes Research, Düsseldorf, Germany
- German Center for Diabetes Research, München-Neuherberg, Germany
| | - Julia Szendroedi
- Institute for Clinical Diabetology, German Diabetes Center at Heinrich Heine University, Leibniz Institute for Diabetes Research, Düsseldorf, Germany
- German Center for Diabetes Research, München-Neuherberg, Germany
- Division of Endocrinology and Diabetology, Medical Faculty, Heinrich Heine University, Düsseldorf, Germany
| | - Volker Burkart
- Institute for Clinical Diabetology, German Diabetes Center at Heinrich Heine University, Leibniz Institute for Diabetes Research, Düsseldorf, Germany
- German Center for Diabetes Research, München-Neuherberg, Germany
| | - Jong-Hee Hwang
- Institute for Clinical Diabetology, German Diabetes Center at Heinrich Heine University, Leibniz Institute for Diabetes Research, Düsseldorf, Germany
- German Center for Diabetes Research, München-Neuherberg, Germany
| | - Michael Roden
- Institute for Clinical Diabetology, German Diabetes Center at Heinrich Heine University, Leibniz Institute for Diabetes Research, Düsseldorf, Germany
- German Center for Diabetes Research, München-Neuherberg, Germany
- Division of Endocrinology and Diabetology, Medical Faculty, Heinrich Heine University, Düsseldorf, Germany
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Exploring Liver Mitochondrial Function by 13C-Stable Isotope Breath Tests: Implications in Clinical Biochemistry. Methods Mol Biol 2021; 2310:179-199. [PMID: 34096004 DOI: 10.1007/978-1-0716-1433-4_11] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The liver is at the crossroad of key metabolic processes, which include detoxification, glycolipidic storage and export, and protein synthesis. The gut-liver axis, moreover, provides hepatocytes with a series of bacterial products and metabolites, which contribute to maintain liver function in health and disease. Breath tests (BTs) are developed as diagnostic tools for indirect, rapid, noninvasive assessment of several metabolic processes in the liver. BTs monitor the appearance of CO2 in breath as a marker of a specific substrate metabolized in the liver, typically within microsomes, cytosol, or mitochondria. The noninvasiveness of BTs originates from the use of the, nonradioactive, naturally occurring stable isotope 13C marking a specific substrate which is metabolized in the liver, leading to the appearance of 13CO2 in expired air. Some substrates (ketoisocaproic acid, methionine, and octanoic acid) provide information about dynamic liver mitochondrial function in health and disease. In humans, the application of 13C-breath tests ranges from nonalcoholic and alcoholic liver diseases to liver cirrhosis, hepatocarcinoma, preoperative and postoperative assessment of liver function, and drug-induced liver damage. 13C-BTs are an indirect, cost-effective, and easy method to evaluate dynamic liver function and gastric kinetics in health and disease, with ongoing studies focusing on further applications in clinical medicine.
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Grattagliano I, Di Ciaula A, Baj J, Molina-Molina E, Shanmugam H, Garruti G, Wang DQH, Portincasa P. Protocols for Mitochondria as the Target of Pharmacological Therapy in the Context of Nonalcoholic Fatty Liver Disease (NAFLD). Methods Mol Biol 2021; 2310:201-246. [PMID: 34096005 PMCID: PMC8580566 DOI: 10.1007/978-1-0716-1433-4_12] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Nonalcoholic fatty liver disease (NAFLD) is one of the most frequent metabolic chronic liver diseases in developed countries and puts the populations at risk of progression to liver necro-inflammation, fibrosis, cirrhosis, and hepatocellular carcinoma. Mitochondrial dysfunction is involved in the onset of NAFLD and contributes to the progression from NAFLD to nonalcoholic steatohepatitis (NASH). Thus, liver mitochondria could become the target for treatments for improving liver function in NAFLD patients. This chapter describes the most important steps used for potential therapeutic interventions in NAFLD patients, discusses current options gathered from both experimental and clinical evidence, and presents some novel options for potentially improving mitochondrial function in NAFLD.
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Affiliation(s)
- Ignazio Grattagliano
- Clinica Medica "A. Murri", Department of Biomedical Sciences and Human Oncology, University of Bari Medical School, Bari, Italy
- Italian College of General Practitioners and Primary Care, Bari, Italy
| | - Agostino Di Ciaula
- Clinica Medica "A. Murri", Department of Biomedical Sciences and Human Oncology, University of Bari Medical School, Bari, Italy
| | - Jacek Baj
- Department of Anatomy, Medical University of Lublin, Lublin, Poland
| | - Emilio Molina-Molina
- Clinica Medica "A. Murri", Department of Biomedical Sciences and Human Oncology, University of Bari Medical School, Bari, Italy
| | - Harshitha Shanmugam
- Clinica Medica "A. Murri", Department of Biomedical Sciences and Human Oncology, University of Bari Medical School, Bari, Italy
| | - Gabriella Garruti
- Section of Endocrinology, Department of Emergency and Organ Transplantations, University of Bari "Aldo Moro" Medical School, Bari, Italy
| | - David Q-H Wang
- Division of Gastroenterology and Liver Diseases, Department of Medicine and Genetics, Marion Bessin Liver Research Center, Einstein-Mount Sinai Diabetes Research Center, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Piero Portincasa
- Clinica Medica "A. Murri", Department of Biomedical Sciences and Human Oncology, University of Bari Medical School, Bari, Italy.
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Mikolasevic I, Domislovic V, Turk Wensveen T, Delija B, Klapan M, Juric T, Lukic A, Mijic A, Skenderevic N, Puz P, Ostojic A, Krznaric Z, Radic-Kristo D, Filipec Kanizaj T, Stimac D. Screening for nonalcoholic fatty liver disease in patients with type 2 diabetes mellitus using transient elastography - a prospective, cross sectional study. Eur J Intern Med 2020; 82:68-75. [PMID: 32839076 DOI: 10.1016/j.ejim.2020.08.005] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/17/2020] [Revised: 06/22/2020] [Accepted: 08/01/2020] [Indexed: 02/08/2023]
Abstract
AIM To investigate the prevalence and severity of nonalcoholic fatty liver disease (NAFLD) in patients with diabetes mellitus type 2 (T2DM), based on increased controlled attenuation parameter (CAP) and liver stiffness measurements obtained by transient elastography. In addition, we aimed to identify parameters that correlate with increased elastographic parameters of steatosis and fibrosis to provide a better indication when a patient with T2DM should be screened for NAFLD. METHODS We conducted prospective, cross-sectional study of 679 consecutive adult patients with diagnosed T2DM mean age 65.2±11.6. NAFLD was defined by transient elastography. In 105 patients a percutaneous liver biopsy (LB) was done. RESULTS The prevalence of NAFLD based on transient elastography was 83.6%. Independent factors associated with increased CAP were higher body mass index, longer T2DM duration, higher serum triglyceride, lower levels of vitamin D, higher C-reactive protein, and higher HOMA-IR. The prevalence of moderate liver fibrosis was 26.9% and advanced liver fibrosis 12.6%. Independent factors associated with moderated fibrosis based on elastography were higher body mass index and higher levels of alanine aminotransferase (ALT), while independent factors associated with advanced fibrosis were female gender, higher body mass index, higher levels of ALT, gama-glutamil transferase and C-reactive protein. Sixty-four (60.9%) of 105 patients with LB had NAFLD activity score ≥5. Regarding the presence and stages of fibrosis based on LB, moderate fibrosis was found in 29.5% of patients, while 29.5% had advanced fibrosis and 6.7% cirrhosis. CONCLUSION This study supports more aggressive screening for NAFLD and fibrosis in patients with T2DM.
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Affiliation(s)
- I Mikolasevic
- Department of Gastroenterology, University Hospital Center Rijeka, Rijeka, Croatia; Department of Gastroenterology, University Hospital Merkur, Zagreb, Croatia; School of Medicine, Rijeka, Croatia.
| | - V Domislovic
- Department for Gastroenterology and Hepatology, University Hospital Center Zagreb, Zagreb, Croatia
| | - T Turk Wensveen
- School of Medicine, Rijeka, Croatia; Department of Endocrinology, University Hospital Center Rijeka, Rijeka, Croatia
| | - B Delija
- School of Medicine, Rijeka, Croatia
| | - M Klapan
- School of Medicine, Rijeka, Croatia
| | - T Juric
- School of Medicine, Rijeka, Croatia
| | - A Lukic
- School of Medicine, Rijeka, Croatia
| | - A Mijic
- School of Medicine, Rijeka, Croatia
| | - N Skenderevic
- Department of Gastroenterology, University Hospital Merkur, Zagreb, Croatia
| | - P Puz
- Internal Medicine, General Hospital Koprivnica, Koprivnica, Croatia
| | - A Ostojic
- Department of Gastroenterology, University Hospital Merkur, Zagreb, Croatia
| | - Z Krznaric
- Department for Gastroenterology and Hepatology, University Hospital Center Zagreb, Zagreb, Croatia; School of Medicine, Zagreb, Croatia
| | - D Radic-Kristo
- Department of Hematology, University Hospital Merkur, Zagreb, Croatia; School of Medicine, Osijek, Croatia
| | - T Filipec Kanizaj
- Department of Gastroenterology, University Hospital Merkur, Zagreb, Croatia; School of Medicine, Zagreb, Croatia
| | - D Stimac
- Department of Gastroenterology, University Hospital Center Rijeka, Rijeka, Croatia; School of Medicine, Rijeka, Croatia
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Dewidar B, Kahl S, Pafili K, Roden M. Metabolic liver disease in diabetes - From mechanisms to clinical trials. Metabolism 2020; 111S:154299. [PMID: 32569680 PMCID: PMC7305712 DOI: 10.1016/j.metabol.2020.154299] [Citation(s) in RCA: 87] [Impact Index Per Article: 21.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/25/2020] [Revised: 06/04/2020] [Accepted: 06/18/2020] [Indexed: 12/12/2022]
Abstract
Non-alcoholic fatty liver disease (NAFLD) comprises fatty liver (steatosis), non-alcoholic steatohepatitis (NASH) and fibrosis/cirrhosis and may lead to end-stage liver failure or hepatocellular carcinoma. NAFLD is tightly associated with the most frequent metabolic disorders, such as obesity, metabolic syndrome, and type 2 diabetes mellitus (T2DM). Both multisystem diseases share several common mechanisms. Alterations of tissue communications include excessive lipid and later cytokine release by dysfunctional adipose tissue, intestinal dysbiosis and ectopic fat deposition in skeletal muscle. On the hepatocellular level, this leads to insulin resistance due to abnormal lipid handling and mitochondrial function. Over time, cellular oxidative stress and activation of inflammatory pathways, again supported by multiorgan crosstalk, determine NAFLD progression. Recent studies show that particularly the severe insulin resistant diabetes (SIRD) subgroup (cluster) associates with NAFLD and its accelerated progression and increases the risk of diabetes-related cardiovascular and kidney diseases, underpinning the critical role of insulin resistance. Consequently, lifestyle modification and certain drug classes used to treat T2DM have demonstrated effectiveness for treating NAFLD, but also some novel therapeutic concepts may be beneficial for both NAFLD and T2DM. This review addresses the bidirectional relationship between mechanisms underlying T2DM and NAFLD, the relevance of novel biomarkers for improving the diagnostic modalities and the identification of subgroups at specific risk of disease progression. Also, the role of metabolism-related drugs in NAFLD is discussed in light of the recent clinical trials. Finally, this review highlights some challenges to be addressed by future studies on NAFLD in the context of T2DM.
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Affiliation(s)
- Bedair Dewidar
- Institute of Clinical Diabetology, German Diabetes Center, Düsseldorf, Germany; German Center for Diabetes Research, München-Neuherberg, Germany; Department of Pharmacology and Toxicology, Faculty of Pharmacy, Tanta University, Tanta, Egypt
| | - Sabine Kahl
- Institute of Clinical Diabetology, German Diabetes Center, Düsseldorf, Germany; German Center for Diabetes Research, München-Neuherberg, Germany
| | - Kalliopi Pafili
- Institute of Clinical Diabetology, German Diabetes Center, Düsseldorf, Germany
| | - Michael Roden
- Institute of Clinical Diabetology, German Diabetes Center, Düsseldorf, Germany; German Center for Diabetes Research, München-Neuherberg, Germany; Division of Endocrinology and Diabetology, Medical Faculty, Heinrich-Heine University, Düsseldorf, Germany.
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Muyyarikkandy MS, McLeod M, Maguire M, Mahar R, Kattapuram N, Zhang C, Surugihalli C, Muralidaran V, Vavilikolanu K, Mathews CE, Merritt ME, Sunny NE. Branched chain amino acids and carbohydrate restriction exacerbate ketogenesis and hepatic mitochondrial oxidative dysfunction during NAFLD. FASEB J 2020; 34:14832-14849. [PMID: 32918763 DOI: 10.1096/fj.202001495r] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Revised: 08/10/2020] [Accepted: 08/24/2020] [Indexed: 12/16/2022]
Abstract
Mitochondrial adaptation during non-alcoholic fatty liver disease (NAFLD) include remodeling of ketogenic flux and sustained tricarboxylic acid (TCA) cycle activity, which are concurrent to onset of oxidative stress. Over 70% of obese humans have NAFLD and ketogenic diets are common weight loss strategies. However, the effectiveness of ketogenic diets toward alleviating NAFLD remains unclear. We hypothesized that chronic ketogenesis will worsen metabolic dysfunction and oxidative stress during NAFLD. Mice (C57BL/6) were kept (for 16-wks) on either a low-fat, high-fat, or high-fat diet supplemented with 1.5X branched chain amino acids (BCAAs) by replacing carbohydrate calories (ketogenic). The ketogenic diet induced hepatic lipid oxidation and ketogenesis, and produced multifaceted changes in flux through the individual steps of the TCA cycle. Higher rates of hepatic oxidative fluxes fueled by the ketogenic diet paralleled lower rates of de novo lipogenesis. Interestingly, this metabolic remodeling did not improve insulin resistance, but induced fibrogenic genes and inflammation in the liver. Under a chronic "ketogenic environment," the hepatocyte diverted more acetyl-CoA away from lipogenesis toward ketogenesis and TCA cycle, a milieu which can hasten oxidative stress and inflammation. In summary, chronic exposure to ketogenic environment during obesity and NAFLD has the potential to aggravate hepatic mitochondrial dysfunction.
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Affiliation(s)
| | - Marc McLeod
- Department of Biochemistry and Molecular Biology, College of Medicine, University of Florida, Gainesville, FL, USA
| | - Meghan Maguire
- Department of Animal and Avian Sciences, University of Maryland, College Park, MD, USA
| | - Rohit Mahar
- Department of Biochemistry and Molecular Biology, College of Medicine, University of Florida, Gainesville, FL, USA
| | - Nathan Kattapuram
- Department of Animal and Avian Sciences, University of Maryland, College Park, MD, USA
| | - Christine Zhang
- Department of Animal and Avian Sciences, University of Maryland, College Park, MD, USA
| | - Chaitra Surugihalli
- Department of Animal and Avian Sciences, University of Maryland, College Park, MD, USA
| | - Vaishna Muralidaran
- Department of Animal and Avian Sciences, University of Maryland, College Park, MD, USA
| | - Kruthi Vavilikolanu
- Department of Animal and Avian Sciences, University of Maryland, College Park, MD, USA
| | - Clayton E Mathews
- Department of Biochemistry and Molecular Biology, College of Medicine, University of Florida, Gainesville, FL, USA
| | - Matthew E Merritt
- Department of Biochemistry and Molecular Biology, College of Medicine, University of Florida, Gainesville, FL, USA
| | - Nishanth E Sunny
- Department of Animal and Avian Sciences, University of Maryland, College Park, MD, USA
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