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Ji L, Lou S, Fang Y, Wang X, Zhu W, Liang G, Lee K, Luo W, Zhuang Z. Patchouli Alcohol Protects the Heart against Diabetes-Related Cardiomyopathy through the JAK2/STAT3 Signaling Pathway. Pharmaceuticals (Basel) 2024; 17:631. [PMID: 38794201 PMCID: PMC11124524 DOI: 10.3390/ph17050631] [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: 02/08/2024] [Revised: 04/20/2024] [Accepted: 04/29/2024] [Indexed: 05/26/2024] Open
Abstract
Diabetic cardiomyopathy (DCM) represents a common pathological state brought about by diabetes mellitus (DM). Patchouli alcohol (PatA) is known for its diverse advantageous effects, notably its anti-inflammatory properties and protective role against metabolic disorders. Despite this, the influence of PatA on DCM remains relatively unexplored. To explore the effect of PatA on diabetes-induced cardiac injury and dysfunction in mice, streptozotocin (STZ) was used to mimic type 1 diabetes in mice. Serological markers and echocardiography show that PatA treatment protects the heart against cardiomyopathy by controlling myocardial fibrosis but not by reducing hyperglycemia in diabetic mice. Discovery Studio 2017 software was used to perform reverse target screening of PatA, and we found that JAK2 may be a potential target of PatA. RNA-seq analysis of heart tissues revealed that PatA activity in the myocardium was primarily associated with the inflammatory fibrosis through the Janus tyrosine kinase 2 (JAK2)/signal transducer and activator of the transcription 3 (STAT3) pathway. In vitro, we also found that PatA alleviates high glucose (HG) + palmitic acid (PA)-induced fibrotic and inflammatory responses via inhibiting the JAK2/STAT3 signaling pathway in H9C2 cells. Our findings illustrate that PatA mitigates the effects of HG + PA- or STZ-induced cardiomyopathy by acting on the JAK2/STAT3 signaling pathway. These insights indicate that PatA could potentially serve as a therapeutic agent for DCM treatment.
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Affiliation(s)
- Lijun Ji
- The Affiliated Cangnan Hospital and Chemical Biology Research Center, Wenzhou Medical University, Wenzhou 325000, China; (L.J.); (S.L.); (Y.F.); (X.W.); (W.Z.); (G.L.)
- College of Pharmacy, Chonnam National University, Gwangju 61186, Republic of Korea;
| | - Shuaijie Lou
- The Affiliated Cangnan Hospital and Chemical Biology Research Center, Wenzhou Medical University, Wenzhou 325000, China; (L.J.); (S.L.); (Y.F.); (X.W.); (W.Z.); (G.L.)
| | - Yi Fang
- The Affiliated Cangnan Hospital and Chemical Biology Research Center, Wenzhou Medical University, Wenzhou 325000, China; (L.J.); (S.L.); (Y.F.); (X.W.); (W.Z.); (G.L.)
| | - Xu Wang
- The Affiliated Cangnan Hospital and Chemical Biology Research Center, Wenzhou Medical University, Wenzhou 325000, China; (L.J.); (S.L.); (Y.F.); (X.W.); (W.Z.); (G.L.)
| | - Weiwei Zhu
- The Affiliated Cangnan Hospital and Chemical Biology Research Center, Wenzhou Medical University, Wenzhou 325000, China; (L.J.); (S.L.); (Y.F.); (X.W.); (W.Z.); (G.L.)
| | - Guang Liang
- The Affiliated Cangnan Hospital and Chemical Biology Research Center, Wenzhou Medical University, Wenzhou 325000, China; (L.J.); (S.L.); (Y.F.); (X.W.); (W.Z.); (G.L.)
- School of Pharmaceutical Sciences, Hangzhou Medical College, Hangzhou 311399, China
| | - Kwangyoul Lee
- College of Pharmacy, Chonnam National University, Gwangju 61186, Republic of Korea;
| | - Wu Luo
- The Affiliated Cangnan Hospital and Chemical Biology Research Center, Wenzhou Medical University, Wenzhou 325000, China; (L.J.); (S.L.); (Y.F.); (X.W.); (W.Z.); (G.L.)
- School of Pharmaceutical Sciences, Hangzhou Medical College, Hangzhou 311399, China
| | - Zaishou Zhuang
- The Affiliated Cangnan Hospital and Chemical Biology Research Center, Wenzhou Medical University, Wenzhou 325000, China; (L.J.); (S.L.); (Y.F.); (X.W.); (W.Z.); (G.L.)
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Yang CW, Liu HM, Chang ZY, Liu GH, Chang HH, Huang PY, Lee TY. Puerarin Modulates Hepatic Farnesoid X Receptor and Gut Microbiota in High-Fat Diet-Induced Obese Mice. Int J Mol Sci 2024; 25:5274. [PMID: 38791314 PMCID: PMC11121391 DOI: 10.3390/ijms25105274] [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: 04/24/2024] [Revised: 05/04/2024] [Accepted: 05/06/2024] [Indexed: 05/26/2024] Open
Abstract
Obesity is associated with alterations in lipid metabolism and gut microbiota dysbiosis. This study investigated the effects of puerarin, a bioactive isoflavone, on lipid metabolism disorders and gut microbiota in high-fat diet (HFD)-induced obese mice. Supplementation with puerarin reduced plasma alanine aminotransferase, liver triglyceride, liver free fatty acid (FFA), and improved gut microbiota dysbiosis in obese mice. Puerarin's beneficial metabolic effects were attenuated when farnesoid X receptor (FXR) was antagonized, suggesting FXR-mediated mechanisms. In hepatocytes, puerarin ameliorated high FFA-induced sterol regulatory element-binding protein (SREBP) 1 signaling, inflammation, and mitochondrial dysfunction in an FXR-dependent manner. In obese mice, puerarin reduced liver damage, regulated hepatic lipogenesis, decreased inflammation, improved mitochondrial function, and modulated mitophagy and ubiquitin-proteasome pathways, but was less effective in FXR knockout mice. Puerarin upregulated hepatic expression of FXR, bile salt export pump (BSEP), and downregulated cytochrome P450 7A1 (CYP7A1) and sodium taurocholate transporter (NTCP), indicating modulation of bile acid synthesis and transport. Puerarin also restored gut microbial diversity, the Firmicutes/Bacteroidetes ratio, and the abundance of Clostridium celatum and Akkermansia muciniphila. This study demonstrates that puerarin effectively ameliorates metabolic disturbances and gut microbiota dysbiosis in obese mice, predominantly through FXR-dependent pathways. These findings underscore puerarin's potential as a therapeutic agent for managing obesity and enhancing gut health, highlighting its dual role in improving metabolic functions and modulating microbial communities.
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MESH Headings
- Animals
- Isoflavones/pharmacology
- Gastrointestinal Microbiome/drug effects
- Diet, High-Fat/adverse effects
- Receptors, Cytoplasmic and Nuclear/metabolism
- Mice
- Obesity/metabolism
- Obesity/drug therapy
- Liver/metabolism
- Liver/drug effects
- Male
- Dysbiosis
- Mice, Obese
- Mice, Inbred C57BL
- ATP Binding Cassette Transporter, Subfamily B, Member 11/metabolism
- ATP Binding Cassette Transporter, Subfamily B, Member 11/genetics
- Cholesterol 7-alpha-Hydroxylase/metabolism
- Cholesterol 7-alpha-Hydroxylase/genetics
- Mice, Knockout
- Organic Anion Transporters, Sodium-Dependent/metabolism
- Organic Anion Transporters, Sodium-Dependent/genetics
- Symporters/metabolism
- Symporters/genetics
- Lipid Metabolism/drug effects
- Hepatocytes/metabolism
- Hepatocytes/drug effects
- Akkermansia
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Affiliation(s)
- Ching-Wei Yang
- Graduate Institute of Clinical Medical Sciences, College of Medicine, Chang Gung University, Taoyuan 33302, Taiwan;
- Division of Internal and Pediatric Chinese Medicine, Center for Traditional Chinese Medicine, Chang Gung Memorial Hospital, Linkou 333423, Taiwan
| | - Hsuan-Miao Liu
- Graduate Institute of Traditional Chinese Medicine, School of Chinese Medicine, College of Medicine, Chang Gung University, Taoyuan 33302, Taiwan;
| | - Zi-Yu Chang
- Department of Traditional Chinese Medicine, Chang Gung Memorial Hospital, Keelung 20401, Taiwan;
| | - Geng-Hao Liu
- School of Traditional Chinese Medicine, College of Medicine, Chang Gung University, Taoyuan 333323, Taiwan;
- Division of Acupuncture and Moxibustion, Center for Traditional Chinese Medicine, Chang Gung Memorial Hospital, Taoyuan 333423, Taiwan
- Sleep Center, Chang Gung Memorial Hospital, Taoyuan 333008, Taiwan
| | - Hen-Hong Chang
- Graduate Institute of Integrated Medicine, China Medical University, Taichung 40402, Taiwan;
| | - Po-Yu Huang
- Department of Chinese Medicine, Linsen Chinese Medicine and Kunming Branch, Taipei City Hospital, Taipei 10844, Taiwan
| | - Tzung-Yan Lee
- Graduate Institute of Traditional Chinese Medicine, School of Chinese Medicine, College of Medicine, Chang Gung University, Taoyuan 33302, Taiwan;
- School of Traditional Chinese Medicine, College of Medicine, Chang Gung University, Taoyuan 333323, Taiwan;
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3
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Sumida Y, Yoneda M, Seko Y, Takahashi H, Hara N, Fujii H, Itoh Y, Yoneda M, Nakajima A, Okanoue T. Role of vitamin E in the treatment of non-alcoholic steatohepatitis. Free Radic Biol Med 2021; 177:391-403. [PMID: 34715296 DOI: 10.1016/j.freeradbiomed.2021.10.017] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/01/2021] [Revised: 10/11/2021] [Accepted: 10/12/2021] [Indexed: 12/12/2022]
Abstract
Non-alcoholic steatohepatitis (NASH), a severe form of non-alcoholic fatty liver disease (NAFLD), can progress to cirrhosis, hepatocellular carcinoma (HCC), and hepatic failure/liver transplantation. Indeed, NASH will soon be the leading cause of HCC and liver transplantation. Lifestyle intervention represents the cornerstone of NASH treatment, but it is difficult to sustain. However, no pharmacotherapies for NASH have been approved. Oxidative stress has been implicated as one of the key factors in the pathogenesis of NASH. Systematic reviews with meta-analyses have confirmed that vitamin E reduces transaminase activities and may resolve NASH histopathology without improving hepatic fibrosis. However, vitamin E is not recommended for the treatment of NASH in diabetes, NAFLD without liver biopsy, NASH cirrhosis, or cryptogenic cirrhosis. Nevertheless, vitamin E supplementation may improve clinical outcomes in patients with NASH and bridging fibrosis or cirrhosis. Further studies are warranted to confirm such effects of vitamin E and that it would reduce overall mortality/morbidity without increasing the incidence of cardiovascular events. Future clinical trials of the use of vitamin E in combination with other anti-fibrotic agents may demonstrate an additive or synergistic therapeutic effect. Vitamin E is the first-line pharmacotherapy for NASH, according to the consensus of global academic societies.
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Affiliation(s)
- Yoshio Sumida
- Division of Hepatology and Pancreatology, Department of Internal Medicine, Aichi Medical University, Nagakute, Aichi, Japan.
| | - Masato Yoneda
- Department of Gastroenterology and Hepatology, Yokohama City University Graduate School of Medicine, Yokohama, Japan.
| | - Yuya Seko
- Department of Gastroenterology and Hepatology, Kyoto Prefectural University of Medicine, Kyoto, Japan.
| | | | - Nagisa Hara
- Liver Center, Saga University Hospital, Saga, Japan
| | - Hideki Fujii
- Department of Hepatology, Graduate School of Medicine, Osaka City University, Osaka, Japan.
| | - Yoshito Itoh
- Department of Gastroenterology and Hepatology, Kyoto Prefectural University of Medicine, Kyoto, Japan.
| | - Masashi Yoneda
- Division of Hepatology and Pancreatology, Department of Internal Medicine, Aichi Medical University, Nagakute, Aichi, Japan.
| | - Atsushi Nakajima
- Department of Gastroenterology and Hepatology, Yokohama City University Graduate School of Medicine, Yokohama, Japan.
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Ali LMA, Shaker SA, Pinol R, Millan A, Hanafy MY, Helmy MH, Kamel MA, Mahmoud SA. Effect of superparamagnetic iron oxide nanoparticles on glucose homeostasis on type 2 diabetes experimental model. Life Sci 2020; 245:117361. [PMID: 32001268 DOI: 10.1016/j.lfs.2020.117361] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2019] [Revised: 01/07/2020] [Accepted: 01/24/2020] [Indexed: 01/12/2023]
Abstract
AIMS Evaluation of the anti-diabetic effect of superparamagnetic iron oxide nanoparticles (SPIONs) on Type 2 diabetic rats and compared their effect to metformin treatment. MAIN METHODS Diabetic rats were treated with different doses of nanoparticles one time per week for 4 weeks. Fasting blood glucose level was determined for studied groups during the experimental period (30 days). At the end of the experiment, oral glucose tolerance test was carried out, serum samples were collected for biochemical assays. Then animals were sacrificed to obtain tissues for assessment of glucose transporters, insulin receptors and insulin signaling proteins. KEY FINDING SPIONs treatment normalized fasting blood glucose and lowering insulin level in diabetic rats compared to untreated diabetic rats. SPIONs significantly ameliorate the glucose sensing and the active components of insulin signaling pathway. The anti-diabetic effects of SPIONs may be mediated through its effect on (i) hepatic peroxisome proliferator-activated receptor gamma coactivator 1-alpha content, which induced by SPIONs treatment in a dose-dependent manner, (ii) adipocytokines as SPIONs treated diabetic rats showed significantly higher levels of adiponectin and lower retinol binding protein 4 compared to untreated diabetic rats, (iii) lipid profile as SPIONs treatment significantly corrected the lipid profile in a dose-dependent manner and to a similar extent as metformin or even better. SIGNIFICANCE To our knowledge, this is the first study that explores the anti-diabetic effects of SPIONs on diabetic model.
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Affiliation(s)
- Lamiaa M A Ali
- Department of Biochemistry, Medical Research Institute, University of Alexandria, Alexandria, Egypt.; Institut des Biomolécules Max Mousseron UMR 5247 CNRS, UM-Faculté de Pharmacie, 15 Avenue Charles Flahault, 34093 Montpellier cedex 05, France.
| | - Sara A Shaker
- Department of Biochemistry, Medical Research Institute, University of Alexandria, Alexandria, Egypt
| | - Rafael Pinol
- Instituto de Ciencia de Materiales de Aragon-CSIC, Universidad de Zaragoza, Spain
| | - Angel Millan
- Instituto de Ciencia de Materiales de Aragon-CSIC, Universidad de Zaragoza, Spain.
| | - Mervat Y Hanafy
- Department of Biochemistry, Medical Research Institute, University of Alexandria, Alexandria, Egypt
| | - Madiha H Helmy
- Department of Biochemistry, Medical Research Institute, University of Alexandria, Alexandria, Egypt
| | - Maher A Kamel
- Department of Biochemistry, Medical Research Institute, University of Alexandria, Alexandria, Egypt..
| | - Shimaa A Mahmoud
- Department of Biochemistry, Medical Research Institute, University of Alexandria, Alexandria, Egypt
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Ren L, Han F, Xuan L, Lv Y, Gong L, Yan Y, Wan Z, Guo L, Liu H, Xu B, Sun Y, Yang S, Liu L. Clusterin ameliorates endothelial dysfunction in diabetes by suppressing mitochondrial fragmentation. Free Radic Biol Med 2019; 145:357-373. [PMID: 31614179 DOI: 10.1016/j.freeradbiomed.2019.10.008] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/02/2019] [Revised: 10/10/2019] [Accepted: 10/10/2019] [Indexed: 12/20/2022]
Abstract
Clusterin (CLU) is a stress-responding protein associated with cytoprotection in a broad range of pathological processes. However, clusterin's function in diabetes-induced endothelial dysfunction has not been defined. Herein, using two diabetes models, we investigated the role of clusterin in endothelial dysfunction triggered by diabetes and the molecular mechanisms involved. The results revealed that clusterin overexpression inhibited ICAM-1/VCAM-1 expression in aortas and improved endothelium-dependent vasodilatation in db/db diabetic mice and streptozotocin (STZ)-induced diabetes models. Consistently, in vitro, adenoviral clusterin overexpression reduced the expression of a range of pro-inflammatory cytokines and suppressed monocyte adhesion to endothelial cells subjected to high glucose and high palmitate. Further study indicated that clusterin overexpression mitigated mitochondrial excessive fission and reduced mitochondrial ROS production. Conversely, silencing clusterin aggravated mitochondrial fission and endothelial inflammatory activation in high glucose-exposed endothelial cells. Accumulating evidence indicates that impaired mitochondrial dynamics plays a considerable role in promoting endothelial dysfunction in diabetic subjects. Therefore, treatments targeting mitochondrial undue fission may be promising measures to prevent vascular complications of diabetes. Furthermore, AMP-activated protein kinase (AMPK) activation contributed to the modulation of mitochondrial dynamics executed by clusterin. Mechanistically, clusterin promoted the phosphorylation of AMPKα and its downstream target acetyl-CoA carboxylase (ACC), while the inhibition of AMPKα negated the improvement in mitochondrial dynamics provided by clusterin overexpression. Over all, these findings suggest that clusterin exerts beneficial effects in endothelial cells under diabetic conditions via inhibiting mitochondrial fragmentation mediated by AMPK.
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Affiliation(s)
- Lulu Ren
- Department of Pharmacy, Beijing Chao-Yang Hospital, Capital Medical University, Beijing, 100020, China
| | - Feifei Han
- Department of Pharmacy, Beijing Chao-Yang Hospital, Capital Medical University, Beijing, 100020, China
| | - Lingling Xuan
- Department of Pharmacy, Beijing Chao-Yang Hospital, Capital Medical University, Beijing, 100020, China
| | - Yali Lv
- Department of Pharmacy, Beijing Chao-Yang Hospital, Capital Medical University, Beijing, 100020, China
| | - Lili Gong
- Department of Pharmacy, Beijing Chao-Yang Hospital, Capital Medical University, Beijing, 100020, China
| | - Yan Yan
- Department of Pharmacy, Beijing Chao-Yang Hospital, Capital Medical University, Beijing, 100020, China
| | - Zirui Wan
- Department of Pharmacy, Beijing Chao-Yang Hospital, Capital Medical University, Beijing, 100020, China
| | - Lifang Guo
- Department of Pharmacy, Beijing Chao-Yang Hospital, Capital Medical University, Beijing, 100020, China; School of Life Sciences, Tsinghua University, Beijing, 100084, China
| | - He Liu
- Department of Pharmacy, Beijing Chao-Yang Hospital, Capital Medical University, Beijing, 100020, China
| | - Benshan Xu
- Department of Pharmacy, Beijing Chao-Yang Hospital, Capital Medical University, Beijing, 100020, China
| | - Yuan Sun
- Department of Pharmacy, Beijing Chao-Yang Hospital, Capital Medical University, Beijing, 100020, China
| | - Song Yang
- Department of Pharmacy, Beijing Chao-Yang Hospital, Capital Medical University, Beijing, 100020, China
| | - Lihong Liu
- Department of Pharmacy, Beijing Chao-Yang Hospital, Capital Medical University, Beijing, 100020, China.
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6
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Simoes IC, Janikiewicz J, Bauer J, Karkucinska-Wieckowska A, Kalinowski P, Dobrzyń A, Wolski A, Pronicki M, Zieniewicz K, Dobrzyń P, Krawczyk M, Zischka H, Wieckowski MR, Potes Y. Fat and Sugar-A Dangerous Duet. A Comparative Review on Metabolic Remodeling in Rodent Models of Nonalcoholic Fatty Liver Disease. Nutrients 2019; 11:E2871. [PMID: 31771244 PMCID: PMC6950566 DOI: 10.3390/nu11122871] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2019] [Revised: 11/20/2019] [Accepted: 11/21/2019] [Indexed: 02/07/2023] Open
Abstract
Nonalcoholic fatty liver disease (NAFLD) is a common disease in Western society and ranges from steatosis to steatohepatitis to end-stage liver disease such as cirrhosis and hepatocellular carcinoma. The molecular mechanisms that are involved in the progression of steatosis to more severe liver damage in patients are not fully understood. A deeper investigation of NAFLD pathogenesis is possible due to the many different animal models developed recently. In this review, we present a comparative overview of the most common dietary NAFLD rodent models with respect to their metabolic phenotype and morphological manifestation. Moreover, we describe similarities and controversies concerning the effect of NAFLD-inducing diets on mitochondria as well as mitochondria-derived oxidative stress in the progression of NAFLD.
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Affiliation(s)
- Ines C.M. Simoes
- Nencki Institute of Experimental Biology of Polish Academy of Sciences, 02-093 Warsaw, Poland (J.J.); (A.D.); (P.D.); (Y.P.)
| | - Justyna Janikiewicz
- Nencki Institute of Experimental Biology of Polish Academy of Sciences, 02-093 Warsaw, Poland (J.J.); (A.D.); (P.D.); (Y.P.)
| | - Judith Bauer
- Institute of Toxicology and Environmental Hygiene, Technical University Munich, School of Medicine, Biedersteiner Strasse 29, D-80802 Munich, Germany; (J.B.); (H.Z.)
| | | | - Piotr Kalinowski
- Department of General, Transplant and Liver Surgery, Medical University of Warsaw, 02-091 Warsaw, Poland; (P.K.); (K.Z.)
| | - Agnieszka Dobrzyń
- Nencki Institute of Experimental Biology of Polish Academy of Sciences, 02-093 Warsaw, Poland (J.J.); (A.D.); (P.D.); (Y.P.)
| | - Andrzej Wolski
- Department of Interventional Radiology and Neuroradiology, Medical University of Lublin, 20-090 Lublin, Poland;
| | - Maciej Pronicki
- Department of Pathology, The Children’s Memorial Health Institute, 04-730 Warsaw, Poland; (A.K.-W.); (M.P.)
| | - Krzysztof Zieniewicz
- Department of General, Transplant and Liver Surgery, Medical University of Warsaw, 02-091 Warsaw, Poland; (P.K.); (K.Z.)
| | - Paweł Dobrzyń
- Nencki Institute of Experimental Biology of Polish Academy of Sciences, 02-093 Warsaw, Poland (J.J.); (A.D.); (P.D.); (Y.P.)
| | - Marcin Krawczyk
- Laboratory of Metabolic Liver Diseases, Department of General, Transplant and Liver Surgery, Centre for Preclinical Research, Medical University of Warsaw, 02-091 Warsaw, Poland;
- Department of Medicine II, Saarland University Medical Center, 66421 Homburg, Germany
| | - Hans Zischka
- Institute of Toxicology and Environmental Hygiene, Technical University Munich, School of Medicine, Biedersteiner Strasse 29, D-80802 Munich, Germany; (J.B.); (H.Z.)
- Institute of Molecular Toxicology and Pharmacology, Helmholtz Center Munich, German Research Center for Environmental Health, Ingolstaedter Landstrasse 1, D-85764 Neuherberg, Germany
| | - Mariusz R. Wieckowski
- Nencki Institute of Experimental Biology of Polish Academy of Sciences, 02-093 Warsaw, Poland (J.J.); (A.D.); (P.D.); (Y.P.)
| | - Yaiza Potes
- Nencki Institute of Experimental Biology of Polish Academy of Sciences, 02-093 Warsaw, Poland (J.J.); (A.D.); (P.D.); (Y.P.)
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7
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Léveillé M, Estall JL. Mitochondrial Dysfunction in the Transition from NASH to HCC. Metabolites 2019; 9:E233. [PMID: 31623280 PMCID: PMC6836234 DOI: 10.3390/metabo9100233] [Citation(s) in RCA: 62] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2019] [Revised: 09/26/2019] [Accepted: 10/11/2019] [Indexed: 02/06/2023] Open
Abstract
The liver constantly adapts to meet energy requirements of the whole body. Despite its remarkable adaptative capacity, prolonged exposure of liver cells to harmful environmental cues (such as diets rich in fat, sugar, and cholesterol) results in the development of chronic liver diseases (including non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH)) that can progress to hepatocellular carcinoma (HCC). The pathogenesis of these diseases is extremely complex, multifactorial, and poorly understood. Emerging evidence suggests that mitochondrial dysfunction or maladaptation contributes to detrimental effects on hepatocyte bioenergetics, reactive oxygen species (ROS) homeostasis, endoplasmic reticulum (ER) stress, inflammation, and cell death leading to NASH and HCC. The present review highlights the potential contribution of altered mitochondria function to NASH-related HCC and discusses how agents targeting this organelle could provide interesting treatment strategies for these diseases.
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Affiliation(s)
- Mélissa Léveillé
- Institut de Recherches Cliniques de Montréal (IRCM), Montreal, Quebec, QC H2W 1R7, Canada.
- Faculty of Medicine, University of Montreal, Montreal, Quebec, QC H3G 2M1, Canada.
| | - Jennifer L Estall
- Institut de Recherches Cliniques de Montréal (IRCM), Montreal, Quebec, QC H2W 1R7, Canada.
- Faculty of Medicine, University of Montreal, Montreal, Quebec, QC H3G 2M1, Canada.
- Division of Experimental Medicine, McGill University, Montreal, Quebec, QC H4A 3J1, Canada.
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8
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Guimarães J, Bargut TCL, Mandarim-de-Lacerda CA, Aguila MB. Medium-chain triglyceride reinforce the hepatic damage caused by fructose intake in mice. Prostaglandins Leukot Essent Fatty Acids 2019; 140:64-71. [PMID: 30553406 DOI: 10.1016/j.plefa.2018.11.005] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/17/2018] [Revised: 11/06/2018] [Accepted: 11/08/2018] [Indexed: 01/16/2023]
Abstract
We aimed to investigate the effects of medium-chain triglyceride oil on the high fructose diet-provoked hepatic abnormalities in mice. We used C57bl/6 mice of 3-months-old divided into four groups for 12 weeks: control (C), control with MCT (C-MCT), fructose (F), and fructose with MCT (F-MCT). We investigated food and water intake, body mass, blood pressure, glucose tolerance, plasma and liver biochemistry, hepatic protein and gene expression. There were no changes in body mass, food intake and glucose tolerance among the groups. The F group presented increased water intake and blood pressure associated with hepatic steatosis and elevated de novo lipogenesis, beta-oxidation, mitochondrial biogenesis and inflammation in the liver. Surprisingly, the C-MCT group also showed hepatic steatosis and inflammation in the liver, and the F-MCT group had no exacerbations of fructose-induced abnormalities, showing marked hepatic steatosis, lipogenesis de novo and hepatic inflammation. The MCT oil groups also presented increased beta-oxidation and mitochondrial biogenesis. In conclusion, MCT oil showed detrimental hepatic effects and should be used with caution, especially in the presence of hepatic alterations.
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Affiliation(s)
- Janaina Guimarães
- Laboratory of Morphometry, Metabolism and Cardiovascular Diseases, Biomedical Center, Institute of Biology, State University of Rio de Janeiro, Rio de Janeiro, Brazil
| | | | - Carlos Alberto Mandarim-de-Lacerda
- Laboratory of Morphometry, Metabolism and Cardiovascular Diseases, Biomedical Center, Institute of Biology, State University of Rio de Janeiro, Rio de Janeiro, Brazil.
| | - Marcia Barbosa Aguila
- Laboratory of Morphometry, Metabolism and Cardiovascular Diseases, Biomedical Center, Institute of Biology, State University of Rio de Janeiro, Rio de Janeiro, Brazil
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9
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Oriquat GA, Ali MA, Mahmoud SA, Eid RMHM, Hassan R, Kamel MA. Improving hepatic mitochondrial biogenesis as a postulated mechanism for the antidiabetic effect of Spirulina platensis in comparison with metformin. Appl Physiol Nutr Metab 2018; 44:357-364. [PMID: 30208279 DOI: 10.1139/apnm-2018-0354] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Various nutritional and medicinal potencies have been accredited to metabolites from the cyanobacteria, Spirulina platensis (Arthrospira platensis) sp. Hence, our study was designed to examine whether the Spirulina supplementation would possess beneficial effects in type 2 diabetes mellitus (T2DM) in comparison with metformin. High-fat diet/low-dose streptozotocin (HFD/STZ) model was adopted and the diabetic rats were orally treated with metformin (200 mg/kg) or Spirulina (250 or 500 or 750 mg/kg) for 30 days. Spirulina ameliorated the HFD/STZ-induced elevation of fasting blood glucose, insulin, and hepatic enzymes. Moreover, Spirulina successfully rectified disrupted serum lipid profile and exhibited an anti-inflammatory effect via tumor necrosis factor-α and adiponectin modulation. On the molecular level, Spirulina reduced the expression of hepatic sterol regulatory element binding protein-1c (SREBP-1c), confirming its lipotropic effect. Furthermore, Spirulina amended compromised hepatic mitochondrial biogenesis signaling by significantly increasing peroxisome proliferator-activated receptor-gamma coactivator-1α (PGC-1α), mitochondrial transcription factor A (Tfam), and mitochondrial DNA (mtDNA) copy number. On almost all parameters, the highest dose of Spirulina showed the best effects, which were comparable to that of metformin. To our knowledge, our study is the first to attribute the various aspects of the effect of Spirulina to the SREBP-1c and PGC-1α/Tfam/mtDNA pathways in liver. The present results clearly proved that Spirulina modulated glucose/lipid profile and exhibited prominent anti-inflammatory properties through SREBP-1c inhibition and hepatic mitochondrial biogenesis enhancement. Thus, Spirulina can be considered as an add-on to conventional antidiabetic agents and might influence the whole dynamics of the therapeutic approaches in T2DM.
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Affiliation(s)
- Ghaleb A Oriquat
- a Faculty of Pharmacy and Medical Sciences, Al-Ahliyya Amman University, Amman 19328, Jordan
| | - Mennatallah A Ali
- b Department of Pharmacology & Therapeutics, Faculty of Pharmacy and Drug Manufacturing, Pharos University in Alexandria, PO Box 37, Alexandria 21648, Egypt
| | - Shimaa A Mahmoud
- c Department of Biochemistry, Medical Research Institute, Alexandria University, Alexandria 21561, Egypt
| | - Rania M H M Eid
- d Department of Physiology, Faculty of Medicine, Aswan University, Aswan 81528, Egypt
| | - Rania Hassan
- e Department of Biochemistry, Faculty of Physical Therapy, Pharos University in Alexandria, Alexandria 21648, Egypt
| | - Maher A Kamel
- c Department of Biochemistry, Medical Research Institute, Alexandria University, Alexandria 21561, Egypt
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Ajith TA. Role of mitochondria and mitochondria-targeted agents in non-alcoholic fatty liver disease. Clin Exp Pharmacol Physiol 2017; 45:413-421. [PMID: 29112771 DOI: 10.1111/1440-1681.12886] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2017] [Revised: 10/26/2017] [Accepted: 10/27/2017] [Indexed: 12/18/2022]
Abstract
Mitochondria play a pivotal role in the fatty acid oxidation and have been found to be affected early during the macrovesicular fat accumulation in the hepatocytes. The fatty infiltration is the primary cause of oxidative stress and inflammation in the non-alcoholic fatty liver disease (NAFLD), which can lead to the peroxidation of phospholipids, such as cardiolipin. Oxidative stress-induced damage to mitochondrial DNA can result in the impairment of oxidative phosphorylation and further increases the generation of reactive oxygen species. The mitochondrial damage may eventually lead to apoptotic death of hepatocytes. The apoptosis along with the generated cytokines from the stellate and Kupffer cells further augment the fibrotic changes to advance the disease. Hence, alleviation of the mitochondrial impairment, particularly in the early stages of NAFLD, may prevent the progression of the disease. Among the various experimentally studied mitochondrial-targeted agents, triphenylphosphonium cation ligated ubiquinone Q10 and vitamin E, Szeto-Scheller peptides, and superoxide dismutase mimetic-salen manganese complexes (EUK-8 and EUK-134) have been found to be most promising. In addition to these mitochondrial-targeted agents, a novel area of therapy called mitotherapy have also emerged. However, clinical studies conducted so far are still fragmentary to validate their efficacy. This review article discusses the mitochondria-targeted molecules and their potential role in the treatment of NAFLD.
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Zhang SB, Yang S, Zhang Z, Zhang A, Zhang M, Yin L, Casey-Sawicki K, Swarts S, Vidyasagar S, Zhang L, Okunieff P. Thoracic gamma irradiation-induced obesity in C57BL/6 female mice. Int J Radiat Biol 2017; 93:1334-1342. [DOI: 10.1080/09553002.2017.1385871] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Affiliation(s)
- Steven B. Zhang
- Department of Radiation Oncology, University of Florida Health Cancer Center, Gainesville, FL, USA
| | - Shanmin Yang
- Department of Radiation Oncology, University of Florida Health Cancer Center, Gainesville, FL, USA
| | - Zhenhuan Zhang
- Department of Radiation Oncology, University of Florida Health Cancer Center, Gainesville, FL, USA
| | - Amy Zhang
- Department of Radiation Oncology, University of Florida Health Cancer Center, Gainesville, FL, USA
| | - Mei Zhang
- Department of Radiation Oncology, University of Florida Health Cancer Center, Gainesville, FL, USA
| | - Liangjie Yin
- Department of Radiation Oncology, University of Florida Health Cancer Center, Gainesville, FL, USA
| | - Katherine Casey-Sawicki
- Department of Radiation Oncology, University of Florida Health Cancer Center, Gainesville, FL, USA
| | - Steven Swarts
- Department of Radiation Oncology, University of Florida Health Cancer Center, Gainesville, FL, USA
| | - Sadasivan Vidyasagar
- Department of Radiation Oncology, University of Florida Health Cancer Center, Gainesville, FL, USA
| | - Lurong Zhang
- Department of Radiation Oncology, University of Florida Health Cancer Center, Gainesville, FL, USA
| | - Paul Okunieff
- Department of Radiation Oncology, University of Florida Health Cancer Center, Gainesville, FL, USA
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12
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Tong M, Leão R, Vimbela GV, Yalcin EB, Kay J, Krotow A, de la Monte SM. Altered temporal lobe white matter lipid ion profiles in an experimental model of sporadic Alzheimer's disease. Mol Cell Neurosci 2017; 82:23-34. [PMID: 28438696 DOI: 10.1016/j.mcn.2017.04.010] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2016] [Revised: 02/19/2017] [Accepted: 04/20/2017] [Indexed: 10/19/2022] Open
Abstract
BACKGROUND White matter is an early and important yet under-evaluated target of Alzheimer's disease (AD). Metabolic impairments due to insulin and insulin-like growth factor resistance contribute to white matter degeneration because corresponding signal transduction pathways maintain oligodendrocyte function and survival. METHODS This study utilized a model of sporadic AD in which adult Long Evans rats administered intracerebral streptozotocin (i.c. STZ) developed AD-type neurodegeneration. Temporal lobe white matter lipid ion profiles were characterized by matrix-assisted laser desorption/ionization-imaging mass spectrometry (MALDI-IMS). RESULTS Although the lipid ion species expressed in the i.c. STZ and control groups were virtually identical, i.c. STZ mainly altered the abundances of various lipid ions. Correspondingly, the i.c. STZ group was distinguished from control by principal component analysis and data bar plots. i.c. STZ mainly reduced expression of lipid ions with low m/z's (less than 810) as well as the upper range m/z lipids (m/z 964-986), and increased expression of lipid ions with m/z's between 888 and 937. Phospholipids were mainly included among the clusters inhibited by i.c. STZ, while both sulfatides and phospholipids were increased by i.c. STZ. However, Chi-Square analysis demonstrated significant i.c. STZ-induced trend reductions in phospholipids and increases in sulfatides (P<0.00001). CONCLUSIONS The i.c. STZ model of sporadic AD is associated with broad and sustained abnormalities in temporal lobe white matter lipids. The findings suggest that the i.c. STZ model could be used for pre-clinical studies to assess therapeutic measures for their ability to restore white matter integrity in AD.
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Affiliation(s)
- Ming Tong
- Liver Research Center, Rhode Island Hospital, Warren Alpert Medical School of Brown University, Providence, RI, United States; Division of Gastroenterology, Rhode Island Hospital, Warren Alpert Medical School of Brown University, Providence, RI, United States; Department of Medicine, Rhode Island Hospital, Warren Alpert Medical School of Brown University, Providence, RI, United States
| | - Raiane Leão
- Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Gina V Vimbela
- Department of Chemical Engineering, California State University, Long Beach, CA, United States
| | - Emine B Yalcin
- Liver Research Center, Rhode Island Hospital, Warren Alpert Medical School of Brown University, Providence, RI, United States
| | - Jared Kay
- Liver Research Center, Rhode Island Hospital, Warren Alpert Medical School of Brown University, Providence, RI, United States
| | | | - Suzanne M de la Monte
- Liver Research Center, Rhode Island Hospital, Warren Alpert Medical School of Brown University, Providence, RI, United States; Division of Gastroenterology, Rhode Island Hospital, Warren Alpert Medical School of Brown University, Providence, RI, United States; Division of Neuropathology, Rhode Island Hospital, Warren Alpert Medical School of Brown University, Providence, RI, United States; Department of Medicine, Rhode Island Hospital, Warren Alpert Medical School of Brown University, Providence, RI, United States; Department of Pathology, Rhode Island Hospital, Warren Alpert Medical School of Brown University, Providence, RI, United States; Department of Neurology, Rhode Island Hospital, Warren Alpert Medical School of Brown University, Providence, RI, United States; Department of Neurosurgery, Rhode Island Hospital, Warren Alpert Medical School of Brown University, Providence, RI, United States.
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13
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Spahis S, Delvin E, Borys JM, Levy E. Oxidative Stress as a Critical Factor in Nonalcoholic Fatty Liver Disease Pathogenesis. Antioxid Redox Signal 2017; 26:519-541. [PMID: 27452109 DOI: 10.1089/ars.2016.6776] [Citation(s) in RCA: 263] [Impact Index Per Article: 37.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
SIGNIFICANCE Nonalcoholic fatty liver disease (NAFLD), characterized by liver triacylglycerol build-up, has been growing in the global world in concert with the raised prevalence of cardiometabolic disorders, including obesity, diabetes, and hyperlipemia. Redox imbalance has been suggested to be highly relevant to NAFLD pathogenesis. Recent Advances: As a major health problem, NAFLD progresses to the more severe nonalcoholic steatohepatitis (NASH) condition and predisposes susceptible individuals to liver and cardiovascular disease. Although NAFLD represents the predominant cause of chronic liver disorders, the mechanisms of its development and progression remain incompletely understood, even if various scientific groups ascribed them to the occurrence of insulin resistance, dyslipidemia, inflammation, and apoptosis. Nevertheless, oxidative stress (OxS) more and more appears as the most important pathological event during NAFLD development and the hallmark between simple steatosis and NASH manifestation. CRITICAL ISSUES The purpose of this article is to summarize recent developments in the understanding of NAFLD, essentially focusing on OxS as a major pathogenetic mechanism. Various attempts to translate reactive oxygen species (ROS) scavenging by antioxidants into experimental and clinical studies have yielded mostly encouraging results. FUTURE DIRECTIONS Although augmented concentrations of ROS and faulty antioxidant defense have been associated to NAFLD and related complications, mechanisms of action and proofs of principle should be highlighted to support the causative role of OxS and to translate its concept into the clinic. Antioxid. Redox Signal. 26, 519-541.
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Affiliation(s)
- Schohraya Spahis
- 1 GI-Nutrition Unit, Research Centre, CHU Ste-Justine, Université de Montréal , Montreal, Quebec, Canada .,2 Department of Nutrition, Université de Montréal , Montreal, Quebec, Canada
| | - Edgard Delvin
- 1 GI-Nutrition Unit, Research Centre, CHU Ste-Justine, Université de Montréal , Montreal, Quebec, Canada .,3 Department of Biochemistry, Université de Montréal , Montreal, Quebec, Canada
| | | | - Emile Levy
- 1 GI-Nutrition Unit, Research Centre, CHU Ste-Justine, Université de Montréal , Montreal, Quebec, Canada .,2 Department of Nutrition, Université de Montréal , Montreal, Quebec, Canada .,4 EPODE International Network , Paris, France
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14
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Stahel P, Kim JJ, Cieslar SR, Warrington JM, Xiao C, Cant JP. Supranutritional selenium intake from enriched milk casein impairs hepatic insulin sensitivity via attenuated IRS/PI3K/AKT signaling and decreased PGC-1α expression in male Sprague–Dawley rats. J Nutr Biochem 2017; 41:142-150. [DOI: 10.1016/j.jnutbio.2016.12.012] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2016] [Revised: 11/14/2016] [Accepted: 12/28/2016] [Indexed: 11/28/2022]
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15
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Deochand C, Tong M, Agarwal AR, Cadenas E, de la Monte SM. Tobacco Smoke Exposure Impairs Brain Insulin/IGF Signaling: Potential Co-Factor Role in Neurodegeneration. J Alzheimers Dis 2016; 50:373-86. [PMID: 26682684 DOI: 10.3233/jad-150664] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
BACKGROUND Human studies suggest tobacco smoking is a risk factor for cognitive impairment and neurodegeneration, including Alzheimer's disease (AD). However, experimental data linking tobacco smoke exposures to underlying mediators of neurodegeneration, including impairments in brain insulin and insulin-like growth factor (IGF) signaling in AD are lacking. OBJECTIVE This study tests the hypothesis that cigarette smoke (CS) exposures can impair brain insulin/IGF signaling and alter expression of AD-associated proteins. METHODS Adult male A/J mice were exposed to air for 8 weeks (A8), CS for 4 or 8 weeks (CS4, CS8), or CS8 followed by 2 weeks recovery (CS8+R). Gene expression was measured by qRT-PCR analysis and proteins were measured by multiplex bead-based or direct binding duplex ELISAs. RESULTS CS exposure effects on insulin/IGF and insulin receptor substrate (IRS) proteins and phosphorylated proteins were striking compared with the mRNA. The main consequences of CS4 or CS8 exposures were to significantly reduce insulin R, IGF-1R, IRS-1, and tyrosine phosphorylated insulin R and IGF-1R proteins. Paradoxically, these effects were even greater in the CS8+R group. In addition, relative levels of S312-IRS-1, which inhibits downstream signaling, were increased in the CS4, CS8, and CS8+R groups. Correspondingly, CS and CS8+R exposures inhibited expression of proteins and phosphoproteins required for signaling through Akt, PRAS40, and/or p70S6K, increased AβPP-Aβ, and reduced ASPH protein, which is a target of insulin/IGF-1 signaling. CONCLUSION Secondhand CS exposures caused molecular and biochemical abnormalities in brain that overlap with the findings in AD, and many of these effects were sustained or worsened despite short-term CS withdrawal.
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Affiliation(s)
- Chetram Deochand
- Liver Research Center, Rhode Island Hospital and the Warren Alpert Medical School of Brown University, Providence, RI, USA.,Divisions of Gastroenterology, Rhode Island Hospital and the Warren Alpert Medical School of Brown University, Providence, RI, USA.,Department of Medicine, Rhode Island Hospital and the Warren Alpert Medical School of Brown University, Providence, RI, USA
| | - Ming Tong
- Liver Research Center, Rhode Island Hospital and the Warren Alpert Medical School of Brown University, Providence, RI, USA.,Divisions of Gastroenterology, Rhode Island Hospital and the Warren Alpert Medical School of Brown University, Providence, RI, USA.,Department of Medicine, Rhode Island Hospital and the Warren Alpert Medical School of Brown University, Providence, RI, USA
| | - Amit R Agarwal
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA, USA
| | - Enrique Cadenas
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA, USA
| | - Suzanne M de la Monte
- Liver Research Center, Rhode Island Hospital and the Warren Alpert Medical School of Brown University, Providence, RI, USA.,Divisions of Gastroenterology, Rhode Island Hospital and the Warren Alpert Medical School of Brown University, Providence, RI, USA.,Divisions of Neuropathology, Rhode Island Hospital and the Warren Alpert Medical School of Brown University, Providence, RI, USA.,Department of Medicine, Rhode Island Hospital and the Warren Alpert Medical School of Brown University, Providence, RI, USA.,Department of Pathology, Rhode Island Hospital and the Warren Alpert Medical School of Brown University, Providence, RI, USA.,Department of Neurology, Rhode Island Hospital and the Warren Alpert Medical School of Brown University, Providence, RI, USA.,Department of Neurosurgery, Rhode Island Hospital and the Warren Alpert Medical School of Brown University, Providence, RI, USA
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Noninvasive mapping of the redox status of dimethylnitrosamine-induced hepatic fibrosis using in vivo dynamic nuclear polarization-magnetic resonance imaging. Sci Rep 2016; 6:32604. [PMID: 27587186 PMCID: PMC5009327 DOI: 10.1038/srep32604] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2016] [Accepted: 08/09/2016] [Indexed: 12/13/2022] Open
Abstract
Hepatic fibrosis is a chronic disorder caused by viral infection and/or metabolic, genetic and cholestatic disorders. A noninvasive procedure that enables the detection of liver fibrosis based on redox status would be useful for disease identification and monitoring, and the development of treatments. However, an appropriate technique has not been reported. This study describes a novel method for assessing the redox status of the liver using in vivo dynamic nuclear polarization-magnetic resonance imaging (DNP-MRI) with the nitroxyl radical carbamoyl-PROXYL as a molecular imaging probe, which was tested in dimethylnitrosamine-treated mice as a model of liver fibrosis. Based on the pharmacokinetics of carbamoyl-PROXYL in control livers, reduction rate mapping was performed in fibrotic livers. Reduction rate maps demonstrated a clear difference between the redox status of control and fibrotic livers according to the expression of antioxidants. These findings indicate that in vivo DNP-MRI with a nitroxyl radical probe enables noninvasive detection of changes in liver redox status.
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17
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Chen CC, Lee TY, Kwok CF, Hsu YP, Shih KC, Lin YJ, Ho LT. Cannabinoid receptor type 1 mediates high-fat diet-induced insulin resistance by increasing forkhead box O1 activity in a mouse model of obesity. Int J Mol Med 2016; 37:743-54. [PMID: 26847930 DOI: 10.3892/ijmm.2016.2475] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2015] [Accepted: 12/09/2015] [Indexed: 11/05/2022] Open
Abstract
Hepatic glucose production is promoted by forkhead box O1 (FoxO1) under conditions of insulin resistance. The overactivity of cannabinoid receptor type 1 (CB1R) partly causes increased liver fat deposits and metabolic dysfunction in obese rodents by decreasing mitochondrial function. The aim of the present study was to investigate the role of FoxO1 in CB1R-mediated insulin resistance through the dysregulation of mitochondrial function in the livers of mice with high-fat diet (HFD)-induced obesity. For this purpose, male C57BL/6 mice were randomly assigned to groups and either fed a standard diet (STD), a HFD, or a HFD with 1-week treatment of the CB1R inverse agonist, AM251, at 1 or 5 mg/kg. For in vitro experiments, AML12 hepatocytes were incubated with FoxO1 siRNA prior to challenge with arachidonyl-2'-chloroethylamide (ACEA) or a high concentration of free fatty acids (HFFA). Plasma parameters were analyzed using colorimetric methods. Liver histopathology and hepatic status markers were examined. The HFD-fed mice exhibited an increase in CB1R levels in the liver. Moreover, in response to increased hepatic oxidative stress, the HFD-fed mice also displayed hepatic mitochondrial dysfunction, as indicated by the decreased mRNA levels of carnitine palmitoyltransferase-1 (CPT-1), mitochondrial transcription factor A (TFAM), nuclear respiratory factor-1 (NRF-1) and citrate synthase. On the contrary, these effects in the HFD-fed mice were reversed by treatment with 5 mg/kg AM251. The administration of AM251 suppressed the induction of FoxO1, phosphoenolpyruvate carboxykinase (PEPCK) and glucose 6-phosphatase (G6Pase) expression in the livers of the mice fed a HFD by enhancing the phosphorylation of insulin signaling cascades thus, further lowering the high level of the homeostatic model assessment of insulin resistance (HOMA‑IR) index. In our in vitro experiments, transfection with FoxO1 siRNA prevented the HFFA- and ACEA-induced decrease in the gene expression of mitochondrial biogenesis-related factors, and abrogated the HFFA- and ACEA-induced increase in PEPCK and G6Pase expression. Taken together, our findings suggest that the anti-insulin resistance effect of AM251, which leads to an improvement of mitochondrial function in hepatic steatosis, is mediated through FoxO1.
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Affiliation(s)
- Chin-Chang Chen
- Institute of Physiology, National Yang-Ming University, Taipei, Taiwan, R.O.C
| | - Tzung-Yan Lee
- Graduate Institute of Traditional Chinese Medicine, Chang Gung University, Tao-Yuan, Taiwan, R.O.C
| | - Ching-Fai Kwok
- Division of Endocrinology and Metabolism, Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan, R.O.C
| | - Yung-Pei Hsu
- Department of Medical Research, Taipei Veterans General Hospital, Taipei, Taiwan, R.O.C
| | - Kuang-Chung Shih
- Division of Endocrinology and Metabolism, Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan, R.O.C
| | - Yan-Jie Lin
- Institute of Physiology, National Yang-Ming University, Taipei, Taiwan, R.O.C
| | - Low-Tone Ho
- Institute of Physiology, National Yang-Ming University, Taipei, Taiwan, R.O.C
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Lee SB, Cho HI, Jin YW, Lee EK, Ahn JY, Lee SM. Wild ginseng cambial meristematic cells ameliorate hepatic steatosis and mitochondrial dysfunction in high-fat diet-fed mice. J Pharm Pharmacol 2016; 68:119-27. [DOI: 10.1111/jphp.12487] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2015] [Accepted: 09/12/2015] [Indexed: 12/23/2022]
Abstract
Abstract
Objectives
The aim of this study was to determine the protective mechanisms of wild ginseng cambial meristematic cells (CMCs) on non-alcoholic fatty liver disease in high-fat diet (HFD)-fed mice.
Methods
Male C57BL/6 mice received either normal-fat diet or HFD for 10 weeks along with wild ginseng CMCs (75, 150 and 300 mg/kg) or vehicle (0.5% carboxyl methyl cellulose) by oral administration once a day. Triglyceride and total cholesterol contents were measured in liver and serum samples. Parameters for hepatic lipid metabolism and mitochondria biogenesis were assessed.
Key findings
Treatment with wild ginseng CMCs markedly attenuated body weight, serum and hepatic lipid contents, and serum aminotransferase activity. While wild ginseng CMCs attenuated the increases in sterol regulatory element-binding transcription factor 1 (SREBP-1) and carbohydrate-responsive element-binding protein (ChREBP) expression, it enhanced the increases in carnitine palmitoyltransferase 1A (CPT1A) and peroxisome proliferator-activated receptor alpha (PPAR-α) expression. HFD decreased glutamate dehydrogenase activity and glutathione content, and increased lipid peroxidation, which were all attenuated by wild ginseng CMCs. Furthermore, wild ginseng CMCs enhanced mitochondrial biogenesis-related factors, including peroxisome proliferator-activated receptor-γ co activator 1α (PGC1α), nuclear respiratory factor 1 (NRF1) and mitochondrial transcription factor A (TFAM).
Conclusions
Wild ginseng CMCs protect against HFD-induced liver injury, which prevents lipid accumulation and mitochondrial oxidative stress, and enhances mitochondrial biogenesis.
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Affiliation(s)
- Sang-Bin Lee
- School of Pharmacy, Sungkyunkwan University, Suwon, Republic of Korea
| | - Hong-Ik Cho
- School of Pharmacy, Sungkyunkwan University, Suwon, Republic of Korea
| | - Young-Woo Jin
- Plant Stem Cell Institute, Unhwa Corp., Jeonju, Republic of Korea
| | - Eun-Kyong Lee
- Plant Stem Cell Institute, Unhwa Corp., Jeonju, Republic of Korea
| | - Jeung Youb Ahn
- Plant Stem Cell Institute, Unhwa Corp., Jeonju, Republic of Korea
| | - Sun-Mee Lee
- School of Pharmacy, Sungkyunkwan University, Suwon, Republic of Korea
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Yu R, Deochand C, Krotow A, Leão R, Tong M, Agarwal AR, Cadenas E, de la Monte SM. Tobacco Smoke-Induced Brain White Matter Myelin Dysfunction: Potential Co-Factor Role of Smoking in Neurodegeneration. J Alzheimers Dis 2016; 50:133-48. [PMID: 26639972 PMCID: PMC5577392 DOI: 10.3233/jad-150751] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
BACKGROUND Meta-analysis studies showed that smokers have increased risk for developing Alzheimer's disease (AD) compared with non-smokers, and neuroimaging studies revealed that smoking damages white matter structural integrity. OBJECTIVE The present study characterizes the effects of side-stream (second hand) cigarette smoke (CS) exposures on the expression of genes that regulate oligodendrocyte myelin-synthesis, maturation, and maintenance and neuroglial functions. METHODS Adult male A/J mice were exposed to air (8 weeks; A8), CS (4 or 8 weeks; CS4, CS8), or CS8 followed by 2 weeks recovery (CS8 + R). The frontal lobes were used for histology and qRT-PCR analysis. RESULTS Luxol fast blue, Hematoxylin and Eosin stained histological sections revealed CS-associated reductions in myelin staining intensity and narrowing of the corpus callosum. CS exposures broadly decreased mRNA levels of immature and mature oligodendrocyte myelin-associated, neuroglial, and oligodendrocyte-related transcription factors. These effects were more prominent in the CS8 compared with CS4 group, suggesting that molecular abnormalities linked to white matter atrophy and myelin loss worsen with duration of CS exposure. Recovery normalized or upregulated less than 25% of the suppressed genes; in most cases, inhibition of gene expression was either sustained or exacerbated. CONCLUSION CS exposures broadly inhibit expression of genes needed for myelin synthesis and maintenance. These adverse effects often were not reversed by short-term CS withdrawal. The results support the hypothesis that smoking contributes to white matter degeneration, and therefore could be a key risk factor for a number of neurodegenerative diseases, including AD.
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Affiliation(s)
- Rosa Yu
- Liver Research Center, Divisions of Rhode Island Hospital and the Warren Alpert Medical School of Brown University, Providence, RI, USA
- Gastroenterology and Rhode Island Hospital and the Warren Alpert Medical School of Brown University, Providence, RI, USA
- Medicine, Rhode Island Hospital and the Warren Alpert Medical School of Brown University, Providence, RI, USA
| | - Chetram Deochand
- Liver Research Center, Divisions of Rhode Island Hospital and the Warren Alpert Medical School of Brown University, Providence, RI, USA
- Gastroenterology and Rhode Island Hospital and the Warren Alpert Medical School of Brown University, Providence, RI, USA
- Medicine, Rhode Island Hospital and the Warren Alpert Medical School of Brown University, Providence, RI, USA
- Molecular Pharmacology and Physiology Graduate Program at Brown University, Providence, RI, USA
| | - Alexander Krotow
- Molecular Pharmacology and Physiology Graduate Program at Brown University, Providence, RI, USA
| | - Raiane Leão
- Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Ming Tong
- Liver Research Center, Divisions of Rhode Island Hospital and the Warren Alpert Medical School of Brown University, Providence, RI, USA
- Gastroenterology and Rhode Island Hospital and the Warren Alpert Medical School of Brown University, Providence, RI, USA
- Medicine, Rhode Island Hospital and the Warren Alpert Medical School of Brown University, Providence, RI, USA
| | - Amit R. Agarwal
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA, USA
| | - Enrique Cadenas
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA, USA
| | - Suzanne M. de la Monte
- Liver Research Center, Divisions of Rhode Island Hospital and the Warren Alpert Medical School of Brown University, Providence, RI, USA
- Gastroenterology and Rhode Island Hospital and the Warren Alpert Medical School of Brown University, Providence, RI, USA
- Neuropathology, and Departments of Rhode Island Hospital and the Warren Alpert Medical School of Brown University, Providence, RI, USA
- Medicine, Rhode Island Hospital and the Warren Alpert Medical School of Brown University, Providence, RI, USA
- Pathology, Rhode Island Hospital and the Warren Alpert Medical School of Brown University, Providence, RI, USA
- Neurology, Rhode Island Hospital and the Warren Alpert Medical School of Brown University, Providence, RI, USA
- Neurosurgery, Rhode Island Hospital and the Warren Alpert Medical School of Brown University, Providence, RI, USA
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Yang G, Dou J, Zhang X, Gu W, Lv Z, DU J, Ba J, Mu Y, Lu J. Increased 3β-hydroxysteroid dehydrogenase 2 and 17α-hydroxylase activities in a virilized adolescent female with adrenal adenoma: A case report. Exp Ther Med 2015; 11:530-534. [PMID: 26893641 DOI: 10.3892/etm.2015.2935] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2014] [Accepted: 06/19/2014] [Indexed: 01/04/2023] Open
Abstract
In the present study, the case of a female patient with pseudo-hermaphrodism caused by an androgen-producing adrenocortical tumor is presented, and the possible mechanism is investigated. The expression of the luteinizing hormone/human chorionic gonadotrophin (LH/hCG) receptor in tumor tissues and normal adrenal tissues was analyzed using immunohistochemistry. Furthermore, the activities of 3β-hydroxysteroid dehydrogenase 2 (HSD2), cytochrome P450 17α-hydroxylase (CYP17) and 17β-hydroxysteroid dehydrogenase 3 (HSD3) enzymes were measured using enzyme-linked immunosorbent assay, and the expression levels of 3β-HSD2, 17β-HSD3, CYP17 and LH/hCG receptor mRNA were determined by quantitative polymerase chain reaction (qPCR). Immunohistochemical staining for the LH/hCG receptor was negative in the tumor tissue and positive in the normal adrenal tissue. The activities of 3β-HSD2 and CYP17 in the tumor tissue were higher than those in the normal tissue (P<0.01), whereas the activity of 17β-HSD3 was lower (P<0.01). The mRNA levels of 3β-HSD2 and CYP17 were higher (P<0.01) and the levels of 17β-HSD3 and LH/hCG receptor were lower (P<0.01) in the tumor tissue compared with those of the normal tissue. In conclusion, in the present study, a rare case of virilization by an androgen-producing adrenocortical tumor is present. The results indicate that it may be associated with increased activities of 3β-HSD2 and CYP17 but not with the expression of the LH/hCG receptor.
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Affiliation(s)
- Guoqing Yang
- Department of Endocrinology, PLA General Hospital, Beijing 100853, P.R. China
| | - Jingtao Dou
- Department of Endocrinology, PLA General Hospital, Beijing 100853, P.R. China
| | - Xiaolin Zhang
- Department of Endocrinology, PLA General Hospital, Beijing 100853, P.R. China
| | - Weijun Gu
- Department of Endocrinology, PLA General Hospital, Beijing 100853, P.R. China
| | - Zhaohui Lv
- Department of Endocrinology, PLA General Hospital, Beijing 100853, P.R. China
| | - Jin DU
- Department of Endocrinology, PLA General Hospital, Beijing 100853, P.R. China
| | - Jianming Ba
- Department of Endocrinology, PLA General Hospital, Beijing 100853, P.R. China
| | - Yiming Mu
- Department of Endocrinology, PLA General Hospital, Beijing 100853, P.R. China
| | - Juming Lu
- Department of Endocrinology, PLA General Hospital, Beijing 100853, P.R. China
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Chung B, Stadion M, Schulz N, Jain D, Scherneck S, Joost HG, Schürmann A. The diabetes gene Zfp69 modulates hepatic insulin sensitivity in mice. Diabetologia 2015; 58:2403-13. [PMID: 26232096 PMCID: PMC4572078 DOI: 10.1007/s00125-015-3703-8] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/16/2015] [Accepted: 06/30/2015] [Indexed: 12/19/2022]
Abstract
AIMS/HYPOTHESIS Zfp69 was previously identified by positional cloning as a candidate gene for obesity-associated diabetes. C57BL/6J and New Zealand obese (NZO) mice carry a loss-of-function mutation due to the integration of a retrotransposon. On the NZO background, the Zfp69 locus caused severe hyperglycaemia and loss of beta cells. To provide direct evidence for a causal role of Zfp69, we investigated the effects of its overexpression on both a lean [B6-Tg(Zfp69)] and an obese [NZO/B6-Tg(Zfp69)] background. METHODS Zfp69 transgenic mice were generated by integrating the cDNA into the ROSA locus of the C57BL/6 genome and characterised. RESULTS B6-Tg(Zfp69) mice were normoglycaemic, developed hyperinsulinaemia, and exhibited increased expression of G6pc and Pck1 and slightly reduced phospho-Akt levels in the liver. During OGTTs, glucose clearance was normal but insulin levels were significantly higher in the B6-Tg(Zfp69) than in control mice. The liver fat content and plasma triacylglycerol levels were significantly increased in B6-Tg(Zfp69) and NZO/B6-Tg(Zfp69) mice on a high-fat diet compared with controls. Liver transcriptome analysis of B6-Tg(Zfp69) mice revealed a downregulation of genes involved in glucose and lipid metabolism. Specifically, expression of Nampt, Lpin2, Map2k6, Gys2, Bnip3, Fitm2, Slc2a2, Ppargc1α and Insr was significantly decreased in the liver of B6-Tg(Zfp69) mice compared with wild-type animals. However, overexpression of Zfp69 did not induce overt diabetes with hyperglycaemia and beta cell loss. CONCLUSIONS/INTERPRETATION Zfp69 mediates hyperlipidaemia, liver fat accumulation and mild insulin resistance. However, it does not induce type 2 diabetes, suggesting that the diabetogenic effect of the Zfp69 locus requires synergy with other as yet unidentified genes.
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Affiliation(s)
- Bomee Chung
- Department of Experimental Diabetology, German Institute of Human Nutrition Potsdam-Rebruecke, Arthur-Scheunert-Allee 114-116, D-14558, Nuthetal, Germany
- German Center for Diabetes Research (DZD), Neuherberg, Germany
| | - Mandy Stadion
- Department of Experimental Diabetology, German Institute of Human Nutrition Potsdam-Rebruecke, Arthur-Scheunert-Allee 114-116, D-14558, Nuthetal, Germany
- German Center for Diabetes Research (DZD), Neuherberg, Germany
| | - Nadja Schulz
- Department of Experimental Diabetology, German Institute of Human Nutrition Potsdam-Rebruecke, Arthur-Scheunert-Allee 114-116, D-14558, Nuthetal, Germany
- German Center for Diabetes Research (DZD), Neuherberg, Germany
| | - Deepak Jain
- German Center for Diabetes Research (DZD), Neuherberg, Germany
- Institute of Metabolic Physiology, Heinrich Heine University of Düsseldorf, Universitätsstrasse, 1, D-40225, Duesseldorf, Germany
| | - Stephan Scherneck
- Department of Experimental Diabetology, German Institute of Human Nutrition Potsdam-Rebruecke, Arthur-Scheunert-Allee 114-116, D-14558, Nuthetal, Germany
- German Center for Diabetes Research (DZD), Neuherberg, Germany
| | - Hans-Georg Joost
- Department of Experimental Diabetology, German Institute of Human Nutrition Potsdam-Rebruecke, Arthur-Scheunert-Allee 114-116, D-14558, Nuthetal, Germany
- German Center for Diabetes Research (DZD), Neuherberg, Germany
| | - Annette Schürmann
- Department of Experimental Diabetology, German Institute of Human Nutrition Potsdam-Rebruecke, Arthur-Scheunert-Allee 114-116, D-14558, Nuthetal, Germany.
- German Center for Diabetes Research (DZD), Neuherberg, Germany.
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Tong M, Yu R, Silbermann E, Zabala V, Deochand C, de la Monte SM. Differential Contributions of Alcohol and Nicotine-Derived Nitrosamine Ketone (NNK) to White Matter Pathology in the Adolescent Rat Brain. Alcohol Alcohol 2015; 50:680-9. [PMID: 26373813 DOI: 10.1093/alcalc/agv102] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2014] [Accepted: 08/17/2015] [Indexed: 12/30/2022] Open
Abstract
AIM Epidemiologic studies have demonstrated high rates of smoking among alcoholics, and neuroimaging studies have detected white matter atrophy and degeneration in both smokers and individuals with alcohol-related brain disease (ARBD). These findings suggest that tobacco smoke exposure may be a co-factor in ARBD. The present study examines the differential and additive effects of tobacco-specific nitrosamine (NNK) and ethanol exposures on the structural and functional integrity of white matter in an experimental model. METHODS Adolescent Long Evans rats were fed liquid diets containing 0 or 26% ethanol for 8 weeks. In weeks 3-8, rats were treated with nicotine-derived nitrosamine ketone (NNK) (2 mg/kg, 3×/week) or saline by i.p. injection. In weeks 7-8, the ethanol group was binge-administered ethanol (2 g/kg; 3×/week). RESULTS Ethanol, NNK and ethanol + NNK caused striking degenerative abnormalities in white matter myelin and axons, with accompanying reductions in myelin-associated glycoprotein expression. Quantitative RT-PCR targeted array and heatmap analyses demonstrated that ethanol modestly increased, whereas ethanol + NNK sharply increased expression of immature and mature oligodendroglial genes, and that NNK increased immature but inhibited mature oligodendroglial genes. In addition, NNK modulated expression of neuroglial genes in favor of growth cone collapse and synaptic disconnection. Ethanol- and NNK-associated increases in FOXO1, FOXO4 and NKX2-2 transcription factor gene expression could reflect compensatory responses to brain insulin resistance in this model. CONCLUSION Alcohol and tobacco exposures promote ARBD by impairing myelin synthesis, maturation and integrity via distinct but overlapping mechanisms. Public health measures to reduce ARBD should target both alcohol and tobacco abuses.
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Affiliation(s)
- Ming Tong
- Department of Medicine, Division of Gastroenterology, and the Liver Research Center, Rhode Island Hospital, Providence, RI, USA Warren Alpert Medical School of Brown University, Providence, RI, USA
| | - Rosa Yu
- Departments of Pathology and Neurology, and the Division of Neuropathology, Rhode Island Hospital, Providence, RI, USA
| | | | - Valerie Zabala
- Molecular Pharmacology and Physiology Graduate Program, Brown University, Providence, RI, USA
| | - Chetram Deochand
- Biotechnology Graduate Program, Brown University, Providence, RI, USA
| | - Suzanne M de la Monte
- Department of Medicine, Division of Gastroenterology, and the Liver Research Center, Rhode Island Hospital, Providence, RI, USA Warren Alpert Medical School of Brown University, Providence, RI, USA Departments of Pathology and Neurology, and the Division of Neuropathology, Rhode Island Hospital, Providence, RI, USA
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Tong M, Yu R, Deochand C, de la Monte SM. Differential Contributions of Alcohol and the Nicotine-Derived Nitrosamine Ketone (NNK) to Insulin and Insulin-Like Growth Factor Resistance in the Adolescent Rat Brain. Alcohol Alcohol 2015; 50:670-9. [PMID: 26373814 DOI: 10.1093/alcalc/agv101] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2014] [Accepted: 08/17/2015] [Indexed: 12/11/2022] Open
Abstract
AIMS Since epidemiologic studies suggest that tobacco smoke toxins, e.g. the nicotine-derived nitrosamine ketone (NNK) tobacco-specific nitrosamine, can be a co-factor in alcohol-related brain disease (ARBD), we examined the independent and additive effects of alcohol and NNK exposures on spatial learning/memory, and brain insulin/IGF signaling, neuronal function and oxidative stress. METHODS Adolescent Long Evans rats were fed liquid diets containing 0 or 26% caloric ethanol for 8 weeks. During weeks 3-8, rats were treated with i.p. NNK (2 mg/kg, 3×/week) or saline. In weeks 7-8, ethanol groups were binge-administered ethanol (2 g/kg; 3×/week). In week 8, at 12 weeks of age, rats were subjected to Morris Water Maze tests. Temporal lobes were used to assess molecular indices of insulin/IGF resistance, oxidative stress and neuronal function. RESULTS Ethanol and NNK impaired spatial learning, and NNK ± ethanol impaired memory. Linear trend analysis demonstrated worsening performance from control to ethanol, to NNK, and then ethanol + NNK. Ethanol ± NNK, caused brain atrophy, inhibited insulin signaling through the insulin receptor and Akt, activated GSK-3β, increased protein carbonyl and 3-nitrotyrosine, and reduced acetylcholinesterase. NNK increased NTyr. Ethanol + NNK had synergistic stimulatory effects on 8-iso-PGF-2α, inhibitory effects on p-p70S6K, tau and p-tau and trend effects on insulin-like growth factor type 1 (IGF-1) receptor expression and phosphorylation. CONCLUSIONS Ethanol, NNK and combined ethanol + NNK exposures that begin in adolescence impair spatial learning and memory in young adults. The ethanol and/or NNK exposures differentially impair insulin/IGF signaling through neuronal growth, survival and plasticity pathways, increase cellular injury and oxidative stress and reduce expression of critical proteins needed for neuronal function.
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Affiliation(s)
- Ming Tong
- Department of Medicine, Division of Gastroenterology, and the Liver Research Center, Rhode Island Hospital, Providence, RI, USA Warren Alpert Medical School of Brown University, Providence, RI, USA
| | - Rosa Yu
- Departments of Pathology and Neurology, and the Division of Neuropathology, Rhode Island Hospital, Providence, RI, USA
| | - Chetram Deochand
- Biotechnology Graduate Program, Brown University, Providence, RI, USA
| | - Suzanne M de la Monte
- Department of Medicine, Division of Gastroenterology, and the Liver Research Center, Rhode Island Hospital, Providence, RI, USA Warren Alpert Medical School of Brown University, Providence, RI, USA Departments of Pathology and Neurology, and the Division of Neuropathology, Rhode Island Hospital, Providence, RI, USA
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Protective effects of dietary avocado oil on impaired electron transport chain function and exacerbated oxidative stress in liver mitochondria from diabetic rats. J Bioenerg Biomembr 2015; 47:337-53. [PMID: 26060181 DOI: 10.1007/s10863-015-9614-z] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2014] [Accepted: 05/29/2015] [Indexed: 02/07/2023]
Abstract
Electron transport chain (ETC) dysfunction, excessive ROS generation and lipid peroxidation are hallmarks of mitochondrial injury in the diabetic liver, with these alterations also playing a role in the development of non-alcoholic fatty liver disease (NAFLD). Enhanced mitochondrial sensitivity to lipid peroxidation during diabetes has been also associated to augmented content of C22:6 in membrane phospholipids. Thus, we aimed to test whether avocado oil, a rich source of C18:1 and antioxidants, attenuates the deleterious effects of diabetes on oxidative status of liver mitochondria by decreasing unsaturation of acyl chains of membrane lipids and/or by improving ETC functionality and decreasing ROS generation. Streptozocin-induced diabetes elicited a noticeable increase in the content of C22:6, leading to augmented mitochondrial peroxidizability index and higher levels of lipid peroxidation. Mitochondrial respiration and complex I activity were impaired in diabetic rats with a concomitant increase in ROS generation using a complex I substrate. This was associated to a more oxidized state of glutathione, All these alterations were prevented by avocado oil except by the changes in mitochondrial fatty acid composition. Avocado oil did not prevented hyperglycemia and polyphagia although did normalized hyperlipidemia. Neither diabetes nor avocado oil induced steatosis. These results suggest that avocado oil improves mitochondrial ETC function by attenuating the deleterious effects of oxidative stress in the liver of diabetic rats independently of a hypoglycemic effect or by modifying the fatty acid composition of mitochondrial membranes. These findings might have also significant implications in the progression of NAFLD in experimental models of steatosis.
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Pattern and profile of chronic liver disease in acute on chronic liver failure. Hepatol Int 2015; 9:366-72. [PMID: 26016461 DOI: 10.1007/s12072-015-9627-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/21/2014] [Accepted: 03/30/2015] [Indexed: 12/19/2022]
Abstract
The etiology of the chronic liver disease (CLD) in patients with acute on chronic liver failure (ACLF) may vary from region to region. The major cause of underlying CLD is viral (hepatitis B and C) in the East, while it is alcohol related in the West and in some parts of the Indian subcontinent. Autoimmune liver disease and Wilson's disease are the major underlying etiologies in the pediatric age group. The patients with CLD without cirrhosis should be included when defining ACLF. Non-alcoholic fatty liver disease related chronic liver insult in patients with known risk factors for progressive disease should be taken as a chronic liver disease in the setting of ACLF, whereas fatty liver with normal aminotransferases in low risk patients should not. The patients with CLD and previous decompensation should be excluded. Diagnosis of chronic liver disease in the setting of ACLF is made by history, physical examination and previously available or recent laboratory, endoscopic or radiological investigations. A liver biopsy through the transjugular route may help in cases where the presence of underlying CLD or its cause is not clear. The need of liver biopsy in ACLF should, however, be individualized. Standardization of liver biopsy assessment is essential for a uniform approach to the diagnosis and treatment of CLD and acute insult. Tools to measure liver stiffness may aid in identifying patients with advanced fibrosis. Studies are needed to validate the performance of these tests in the setting of ACLF.
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Zabala V, Tong M, Yu R, Ramirez T, Yalcin EB, Balbo S, Silbermann E, Deochand C, Nunez K, Hecht S, de la Monte SM. Potential contributions of the tobacco nicotine-derived nitrosamine ketone (NNK) in the pathogenesis of steatohepatitis in a chronic plus binge rat model of alcoholic liver disease. Alcohol Alcohol 2015; 50:118-31. [PMID: 25618784 DOI: 10.1093/alcalc/agu083] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
AIMS Alcoholic liver disease (ALD) is linked to binge drinking and cigarette smoking. Heavy chronic ± binge alcohol, or low-level exposures to dietary nitrosamines cause steatohepatitis with insulin resistance and oxidative stress in animal models. This study examines hepatotoxic effects of sub-mutagenic exposures to tobacco-specific nitrosamine (NNK) in relation to ALD. METHODS Long Evans rats were fed liquid diets containing 0 or 26% (caloric) ethanol (EtOH) for 8 weeks. In Weeks 3 through 8, rats were treated with NNK (2 mg/kg) or saline by i.p. injection, 3×/week, and in Weeks 7 and 8, EtOH-fed rats were binge-administered 2 g/kg EtOH 3×/week; controls were given saline. RESULTS EtOH ± NNK caused steatohepatitis with necrosis, disruption of the hepatic cord architecture, ballooning degeneration, early fibrosis, mitochondrial cytopathy and ER disruption. Severity of lesions was highest in the EtOH+NNK group. EtOH and NNK inhibited insulin/IGF signaling through Akt and activated pro-inflammatory cytokines, while EtOH promoted lipid peroxidation, and NNK increased apoptosis. O(6)-methyl-Guanine adducts were only detected in NNK-exposed livers. CONCLUSION Both alcohol and NNK exposures contribute to ALD pathogenesis, including insulin/IGF resistance and inflammation. The differential effects of EtOH and NNK on adduct formation are critical to ALD progression among alcoholics who smoke.
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Affiliation(s)
- Valerie Zabala
- Department of Medicine, Division of Gastroenterology, and The Liver Research Center, Rhode Island Hospital, Providence, RI, USA Department of Molecular Pharmacology and Physiology, Brown University, Providence, RI, USA
| | - Ming Tong
- Department of Medicine, Division of Gastroenterology, and The Liver Research Center, Rhode Island Hospital, Providence, RI, USA Warren Alpert Medical School of Brown University, Providence, RI, USA
| | - Rosa Yu
- Department of Neuroscience, Brown University, Providence, RI, USA
| | - Teresa Ramirez
- Department of Molecular Pharmacology and Physiology, Brown University, Providence, RI, USA
| | - Emine B Yalcin
- Department of Medicine, Division of Gastroenterology, and The Liver Research Center, Rhode Island Hospital, Providence, RI, USA Warren Alpert Medical School of Brown University, Providence, RI, USA
| | - Silvia Balbo
- Masonic Cancer Center, University of Minnesota, Cancer and Cardiovascular Research Building, 2231 6th Street SE, Minneapolis, MN 55455, USA
| | | | - Chetram Deochand
- Biotechnology Graduate Program, Brown University, Providence, RI, USA
| | - Kavin Nunez
- Department of Neuroscience, Brown University, Providence, RI, USA
| | - Stephen Hecht
- Masonic Cancer Center, University of Minnesota, Cancer and Cardiovascular Research Building, 2231 6th Street SE, Minneapolis, MN 55455, USA
| | - Suzanne M de la Monte
- Department of Medicine, Division of Gastroenterology, and The Liver Research Center, Rhode Island Hospital, Providence, RI, USA Warren Alpert Medical School of Brown University, Providence, RI, USA Departments of Pathology and Neurology, and the Division of Neuropathology, Rhode Island Hospital, Providence, RI, USA
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Zhu S, Cheng G, Zhu H, Guan G. A study of genes involved in adipocyte differentiation. J Pediatr Endocrinol Metab 2015; 28:93-9. [PMID: 25153216 DOI: 10.1515/jpem-2014-0002] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/01/2014] [Accepted: 06/20/2014] [Indexed: 11/15/2022]
Abstract
OBJECTIVE With the use of the microarray technique, genes expressed in the late phase of adipocyte differentiation were investigated. These genes play an important role in stimulating adipocyte growth and lipid droplet formation. Therefore, they contribute a great deal to the onset of obesity. METHODS With the use of SW872 adipocytes and the microarray technique, genes related to adipocyte differentiation were tested and compared with undifferentiated preadipocytes 14 days after induction. Real-time reverse transcription polymerase chain reaction (RT-PCR) was used for confirmation. RESULTS More than 21,329 transcriptors were expressed and determined, of which 1326 increased and 687 decreased undifferentiated adipocytes. Among them, 21 were highly expressed by more than 10-fold. With RT-PCR, 12 were confirmed, including apelin, CIDEC, PID1, LYRM1, ADD1, PPARγ2, ANGPTL4, ADIPOQ, ACOX1, FIP1L1, MAP3K2 and PEX14. Furthermore, genes involved in lipid metabolism, signal transduction, DNA replication, redox status and transcription factors were determined as well. Novel genes involved in adipogenesis (e.g., apelin) were detected. CONCLUSION A variety of genes were discovered and validated with RT-PCR at the late phase of adipocyte differentiation. This may help us better understand the onset of obesity and the potential role of adipocytes in other organs.
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Green CJ, Pramfalk C, Morten KJ, Hodson L. From whole body to cellular models of hepatic triglyceride metabolism: man has got to know his limitations. Am J Physiol Endocrinol Metab 2015; 308:E1-20. [PMID: 25352434 PMCID: PMC4281685 DOI: 10.1152/ajpendo.00192.2014] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The liver is a main metabolic organ in the human body and carries out a vital role in lipid metabolism. Nonalcoholic fatty liver disease (NAFLD) is one of the most common liver diseases, encompassing a spectrum of conditions from simple fatty liver (hepatic steatosis) through to cirrhosis. Although obesity is a known risk factor for hepatic steatosis, it remains unclear what factor(s) is/are responsible for the primary event leading to retention of intrahepatocellular fat. Studying hepatic processes and the etiology and progression of disease in vivo in humans is challenging, not least as NAFLD may take years to develop. We present here a review of experimental models and approaches that have been used to assess liver triglyceride metabolism and discuss their usefulness in helping to understand the aetiology and development of NAFLD.
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Affiliation(s)
- Charlotte J Green
- Oxford Centre for Diabetes, Endocrinology and Metabolism, University of Oxford, Churchill Hospital, Oxford United Kingdom; and
| | - Camilla Pramfalk
- Oxford Centre for Diabetes, Endocrinology and Metabolism, University of Oxford, Churchill Hospital, Oxford United Kingdom; and
| | - Karl J Morten
- Nuffield Department of Obstetrics and Gynaecology, University of Oxford, John Radcliffe Hospital, Oxford, United Kingdom
| | - Leanne Hodson
- Oxford Centre for Diabetes, Endocrinology and Metabolism, University of Oxford, Churchill Hospital, Oxford United Kingdom; and
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Affiliation(s)
| | - Akihiko Ohshige
- Digestive and Lifestyle Diseases, Kagoshima University Graduate School of Medical and Dental Sciences
| | - Hirofumi Uto
- Center for Digestive and Liver Diseases, Miyazaki Medical Center Hospital
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Postnatal overfeeding promotes early onset and exaggeration of high-fat diet-induced nonalcoholic fatty liver disease through disordered hepatic lipid metabolism in rats. J Nutr Biochem 2014; 25:1108-1116. [PMID: 25154569 DOI: 10.1016/j.jnutbio.2014.06.010] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2013] [Revised: 04/01/2014] [Accepted: 06/13/2014] [Indexed: 01/03/2023]
Abstract
Exposure to overnutrition in critical or sensitive developmental periods may increase the risk of developing obesity and metabolic syndrome in adults. Nonalcoholic fatty liver disease (NAFLD) is the hepatic manifestation of the metabolic syndrome, but the relationship among postnatal nutrition, lipid metabolism, and NAFLD progression during development remains poorly understood. Here we investigated in a rat model whether postnatal overfeeding increases susceptibility to NAFLD in response to a high-fat diet. Litters from Sprague-Dawley dams were culled to three (small litters) or ten (normal litters) pups and then weaned onto a standard or high-fat diet at postnatal day 21 to generate normal-litter, small-litter, normal-litter/high-fat, and small-litter/high-fat groups. At age 16 weeks, the small-litter and both high-fat groups showed obesity, dyslipidemia, and insulin resistance. Hepatic disorders appeared earlier in the small-litter/high-fat rats with greater liver mass gain and higher hepatic triglycerides and steatosis score versus normal-litter/high-fat rats. Hepatic acetyl-CoA carboxylase activity and mRNA expression were increased in small-litter rats and aggravated in small-litter/high-fat rats but not in normal-litter/high-fat rats. The high expression in small-litter/high-fat rats coincided with high sterol regulatory element-binding protein-1c mRNA and protein expression. However, mRNA expression of enzymes involved in hepatic fatty acid oxidation (carnitine palmitoyltransferase 1) and output (microsomal triglyceride transfer protein) was decreased under a high-fat diet regardless of litter size. In conclusion, overfeeding related to small-litter rearing during lactation contributes to the NAFLD phenotype when combined with a high-fat diet, possibly through up-regulated hepatic lipogenesis.
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Role of Insulin Resistance and Diabetes in the Pathogenesis and Treatment of Nonalcoholic Fatty Liver Disease. ACTA ACUST UNITED AC 2014. [DOI: 10.1007/s11901-014-0229-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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Sahini N, Borlak J. Recent insights into the molecular pathophysiology of lipid droplet formation in hepatocytes. Prog Lipid Res 2014; 54:86-112. [PMID: 24607340 DOI: 10.1016/j.plipres.2014.02.002] [Citation(s) in RCA: 87] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2013] [Revised: 02/17/2014] [Accepted: 02/21/2014] [Indexed: 12/11/2022]
Abstract
Triacyglycerols are a major energy reserve of the body and are normally stored in adipose tissue as lipid droplets (LDs). The liver, however, stores energy as glycogen and digested triglycerides in the form of fatty acids. In stressed condition such as obesity, imbalanced nutrition and drug induced liver injury hepatocytes accumulate excess lipids in the form of LDs whose prolonged storage leads to disease conditions most notably non-alcoholic fatty liver disease (NAFLD). Fatty liver disease has become a major health burden with more than 90% of obese, nearly 70% of overweight and about 25% of normal weight patients being affected. Notably, research in recent years has shown LD as highly dynamic organelles for maintaining lipid homeostasis through fat storage, protein sorting and other molecular events studied in adipocytes and other cells of living organisms. This review focuses on the molecular events of LD formation in hepatocytes and the importance of cross talk between different cell types and their signalling in NAFLD as to provide a perspective on molecular mechanisms as well as possibilities for different therapeutic intervention strategies.
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Affiliation(s)
- Nishika Sahini
- Centre for Pharmacology and Toxicology, Hannover Medical School, 30625 Hannover, Germany
| | - Jürgen Borlak
- Centre for Pharmacology and Toxicology, Hannover Medical School, 30625 Hannover, Germany.
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An Intimate Relationship between ROS and Insulin Signalling: Implications for Antioxidant Treatment of Fatty Liver Disease. Int J Cell Biol 2014; 2014:519153. [PMID: 24672550 PMCID: PMC3944655 DOI: 10.1155/2014/519153] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2013] [Accepted: 12/20/2013] [Indexed: 01/22/2023] Open
Abstract
Oxidative stress damages multiple cellular components including DNA, lipids, and proteins and has been linked to pathological alterations in nonalcoholic fatty liver disease (NAFLD). Reactive oxygen species (ROS) emission, resulting from nutrient overload and mitochondrial dysfunction, is thought to be a principal mediator in NAFLD progression, particularly toward the development of hepatic insulin resistance. In the context of insulin signalling, ROS has a dual role, as both a facilitator and inhibitor of the insulin signalling cascade. ROS mediate these effects through redox modifications of cysteine residues affecting phosphatase enzyme activity, stress-sensitive kinases, and metabolic sensors. This review highlights the intricate relationship between redox-sensitive proteins and insulin signalling in the context of fatty liver disease, and to a larger extent, the importance of reactive oxygen species as primary signalling molecules in metabolically active cells.
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de la Monte SM, Tong M. Brain metabolic dysfunction at the core of Alzheimer's disease. Biochem Pharmacol 2013; 88:548-59. [PMID: 24380887 DOI: 10.1016/j.bcp.2013.12.012] [Citation(s) in RCA: 315] [Impact Index Per Article: 28.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2013] [Revised: 12/16/2013] [Accepted: 12/16/2013] [Indexed: 02/06/2023]
Abstract
Growing evidence supports the concept that Alzheimer's disease (AD) is fundamentally a metabolic disease with molecular and biochemical features that correspond with diabetes mellitus and other peripheral insulin resistance disorders. Brain insulin/IGF resistance and its consequences can readily account for most of the structural and functional abnormalities in AD. However, disease pathogenesis is complicated by the fact that AD can occur as a separate disease process, or arise in association with systemic insulin resistance diseases, including diabetes, obesity, and non-alcoholic fatty liver disease. Whether primary or secondary in origin, brain insulin/IGF resistance initiates a cascade of neurodegeneration that is propagated by metabolic dysfunction, increased oxidative and ER stress, neuro-inflammation, impaired cell survival, and dysregulated lipid metabolism. These injurious processes compromise neuronal and glial functions, reduce neurotransmitter homeostasis, and cause toxic oligomeric pTau and (amyloid beta peptide of amyloid beta precursor protein) AβPP-Aβ fibrils and insoluble aggregates (neurofibrillary tangles and plaques) to accumulate in brain. AD progresses due to: (1) activation of a harmful positive feedback loop that progressively worsens the effects of insulin resistance; and (2) the formation of ROS- and RNS-related lipid, protein, and DNA adducts that permanently damage basic cellular and molecular functions. Epidemiologic data suggest that insulin resistance diseases, including AD, are exposure-related in etiology. Furthermore, experimental and lifestyle trend data suggest chronic low-level nitrosamine exposures are responsible. These concepts offer opportunities to discover and implement new treatments and devise preventive measures to conquer the AD and other insulin resistance disease epidemics.
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Affiliation(s)
- Suzanne M de la Monte
- Departments of Pathology (Neuropathology), Rhode Island Hospital and the Warren Alpert Medical School of Brown University, Providence, RI, USA; Departments of Neurology, Rhode Island Hospital and the Warren Alpert Medical School of Brown University, Providence, RI, USA; Departments of Neurosurgery, Rhode Island Hospital and the Warren Alpert Medical School of Brown University, Providence, RI, USA; Departments of Medicine, Rhode Island Hospital and the Warren Alpert Medical School of Brown University, Providence, RI, USA.
| | - Ming Tong
- Departments of Medicine, Rhode Island Hospital and the Warren Alpert Medical School of Brown University, Providence, RI, USA
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Krautbauer S, Eisinger K, Lupke M, Wanninger J, Ruemmele P, Hader Y, Weiss TS, Buechler C. Manganese superoxide dismutase is reduced in the liver of male but not female humans and rodents with non-alcoholic fatty liver disease. Exp Mol Pathol 2013; 95:330-5. [PMID: 24161595 DOI: 10.1016/j.yexmp.2013.10.003] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2013] [Accepted: 10/11/2013] [Indexed: 12/30/2022]
Abstract
Non-alcoholic fatty liver disease (NAFLD) is among the most common liver diseases. Oxidative stress is one of the pathogenic mechanisms contributing to the progression of simple fatty liver to non-alcoholic steatohepatitis (NASH). Manganese superoxide dismutase (MnSOD) is a mitochondrial antioxidative enzyme and here its expression in rodent and human NAFLD has been analyzed. MnSOD is found reduced in the liver of male mice fed a high fat diet and male ob/ob mice. Female mice fed an atherogenic diet to induce NASH have MnSOD protein levels comparable to controls. In a cohort of 30 controls, 41 patients with fatty liver and 39 NASH patients, MnSOD mRNA is significantly lower in the steatotic and NASH liver. When analyzed in both genders separately reduction of MnSOD expression is only found in males. Here, MnSOD mRNA negatively correlates with steatosis grade but not with extent of fibrosis or inflammation. MnSOD is, however, not reduced in primary human hepatocytes (PHH) treated with palmitate or oleate to increase cellular triglycerides. Lipopolysaccharide, TNF, IL-6, TGFβ and leptin which are all raised in NAFLD do not affect MnSOD in PHH. Adiponectin which attenuates oxidative stress partly by increasing MnSOD in macrophages does not induce MnSOD in PHH. In summary, current data show that hepatic MnSOD is reduced in male but not female humans and rodents with NAFLD.
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Affiliation(s)
- Sabrina Krautbauer
- Department of Internal Medicine I, Regensburg University Hospital, 93042 Regensburg, Germany
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Rigault C, Le Borgne F, Tazir B, Benani A, Demarquoy J. A high-fat diet increases L-carnitine synthesis through a differential maturation of the Bbox1 mRNAs. BIOCHIMICA ET BIOPHYSICA ACTA 2013; 1831:370-7. [PMID: 23127966 DOI: 10.1016/j.bbalip.2012.10.007] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2012] [Revised: 10/15/2012] [Accepted: 10/26/2012] [Indexed: 12/30/2022]
Abstract
l-carnitine is a key molecule in both mitochondrial and peroxisomal lipid metabolisms. l-carnitine is biosynthesized from gamma-butyrobetaine by a reaction catalyzed by the gamma-butyrobetaine hydroxylase (Bbox1). The aim of this work was to identify molecular mechanisms involved in the regulation of l-carnitine biosynthesis and availability. Using 3' RACE, we identified four alternatively polyadenylated Bbox1 mRNAs in rat liver. We utilized a combination of in vitro experiments using hybrid constructs containing the Bbox1 3' UTR and in vivo experiments on rat liver mRNAs to reveal specificities in the different Bbox1 mRNA isoforms, especially in terms of polyadenylation efficiency, mRNA stability and translation efficiency. This complex maturation process of the Bbox1 mRNAs in the liver was studied on rats fed a high-fat diet. High-fat diet selectively increased the level of three Bbox1 mRNA isoforms in rat liver and the alternative use of polyadenylation sites contributed to the global increase in Bbox1 enzymatic activity and l-carnitine levels. Our results show that the maturation of Bbox1 mRNAs is nutritionally regulated in the liver through a selective polyadenylation process to adjust l-carnitine biosynthesis to the energy supply.
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Affiliation(s)
- Caroline Rigault
- Université de Bourgogne, BioperoxIL, EA 7270, Faculté Gabriel, 6 blvd Gabriel, 21000 Dijon, France
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Si M, Yan Y, Tang L, Wu H, Yang B, He Q, Wu H. A novel indole derivative compound GY3 improves glucose and lipid metabolism via activation of AMP-activated protein kinase pathway. Eur J Pharmacol 2013; 698:480-8. [DOI: 10.1016/j.ejphar.2012.10.006] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2012] [Revised: 09/26/2012] [Accepted: 10/08/2012] [Indexed: 01/12/2023]
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Shi W, Hu S, Wang W, Zhou X, Qiu W. Skeletal muscle-specific CPT1 deficiency elevates lipotoxic intermediates but preserves insulin sensitivity. J Diabetes Res 2013; 2013:163062. [PMID: 24319696 PMCID: PMC3844227 DOI: 10.1155/2013/163062] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/08/2013] [Accepted: 10/15/2013] [Indexed: 02/04/2023] Open
Abstract
OBJECTIVE By specific knockout of carnitine palmitoyl transferase 1b (CPT1b) in skeletal muscles, we explored the effect of CPT1b deficiency on lipids and insulin sensitivity. METHODS Mice with specific knockout of CPT1b in skeletal muscles (CPT1b M-/-) were used for the experiment group, with littermate C57BL/6 as controls (CPT1b). General and metabolic profiles were measured and compared between groups. mRNA expression and CPT1 activity were measured in skeletal muscle tissues and compared between groups. Mitochondrial fatty acid oxidation (FAO), triglycerides (TAGs), diglycerides (DAGs), and ceramides were examined in skeletal muscles in two groups. Phosphorylated AKT (pAkt) and glucose transporter 4 (Glut4) were determined with real-time polymerase chain reaction (RT-PCR). Insulin tolerance test, glucose tolerance test, and pyruvate oxidation were performed in both groups. RESULTS CPT1b M-/- model was successfully established, with impaired muscle CPT1 activity. Compared with CPT1b mice, CPT1b M-/- mice had similar food intake but lower body weight or fat mass and higher lipids but similar glucose or insulin levels. Their mitochondrial FAO of skeletal muscles was impaired. There were lipids accumulations (TAGs, DAGs, and ceramides) in skeletal muscle. However, pAkt and Glut4, insulin sensitivity, glucose tolerance, and pyruvate oxidation were preserved. CONCLUSION Skeletal muscle-specific CPT1 deficiency elevates lipotoxic intermediates but preserves insulin sensitivity.
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Affiliation(s)
- Wanchun Shi
- Department of Endocrinology, Huzhou Central Hospital, Zhejiang 313000, China
| | - Siping Hu
- Department of Anesthesiology, Huzhou Central Hospital, Zhejiang 313000, China
| | - Wenhua Wang
- Department of Endocrinology, Huzhou Central Hospital, Zhejiang 313000, China
| | - Xiaohui Zhou
- Department of Endocrinology, Huzhou Central Hospital, Zhejiang 313000, China
| | - Wei Qiu
- Department of Endocrinology, Huzhou Central Hospital, Zhejiang 313000, China
- *Wei Qiu:
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Almon RR, Dubois DC, Sukumaran S, Wang X, Xue B, Nie J, Jusko WJ. Effects of high fat feeding on liver gene expression in diabetic goto-kakizaki rats. GENE REGULATION AND SYSTEMS BIOLOGY 2012; 6:151-68. [PMID: 23236253 PMCID: PMC3516129 DOI: 10.4137/grsb.s10371] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Effects of high fat diet (HFD) on obesity and, subsequently, on diabetes are highly variable and modulated by genetics in both humans and rodents. In this report, we characterized the response of Goto-Kakizaki (GK) rats, a spontaneous polygenic model for lean diabetes and healthy Wistar-Kyoto (WKY) controls, to high fat feeding from weaning to 20 weeks of age. Animals fed either normal diet or HFD were sacrificed at 4, 8, 12, 16 and 20 weeks of age and a wide array of physiological measurements were made along with gene expression profiling using Affymetrix gene array chips. Mining of the microarray data identified differentially regulated genes (involved in inflammation, metabolism, transcription regulation, and signaling) in diabetic animals, as well as the response of both strains to HFD. Functional annotation suggested that HFD increased inflammatory differences between the two strains. Chronic inflammation driven by heightened innate immune response was identified to be present in GK animals regardless of diet. In addition, compensatory mechanisms by which WKY animals on HFD resisted the development of diabetes were identified, thus illustrating the complexity of diabetes disease progression.
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Affiliation(s)
- Richard R Almon
- Department of Biological Sciences, State University of New York at Buffalo, Buffalo, NY, USA. ; Department of Pharmaceutical Sciences, State University of New York at Buffalo, Buffalo, NY, USA. ; New York State Center of Excellence in Bioinformatics and Life Sciences
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Yin Y, Yu Z, Xia M, Luo X, Lu X, Ling W. Vitamin D attenuates high fat diet-induced hepatic steatosis in rats by modulating lipid metabolism. Eur J Clin Invest 2012; 42:1189-96. [PMID: 22958216 DOI: 10.1111/j.1365-2362.2012.02706.x] [Citation(s) in RCA: 91] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
BACKGROUND Vitamin D has been reported to be reversely associated with type 2 diabetes and metabolic syndrome and is involved in modulation of lipid metabolism. The purpose of the present study was to determine whether 1,25-dihydroxyvitamin D(3) (1,25(OH)(2) D(3) ) has a protective effect on high fat diet (HFD)-induced hepatic steatosis in rats and to elucidate its underlying molecular mechanisms. MATERIALS AND METHODS Male Sprague-Dawley (SD) rats were fed with normal fat diet, HFD or HFD with intraperitoneal injection of 1, 2.5 and 5 μg/kg 1,25(OH)(2) D(3) , respectively, each 2 days for 8 weeks. Serum lipid profile and liver triglyceride were determined. Hepatic histology was examined by haematoxylin/eosin (H&E) and Oil Red O stainings. Hepatic gene expression involved in lipogenesis and lipid oxidation was analysed by quantitative reverse transcription-polymerase chain reaction (RT-PCR). RESULTS The administration of 1,25(OH)(2) D(3) prevented HFD-induced body weight gain and reduced liver weight. 1,25(OH)(2) D(3) attenuated hepatic steatosis in a dose-dependent manner along with improved serum lipid profile. Furthermore, 1,25(OH)(2) D(3) downregulated mRNA expression of sterol regulatory element binding protein-1c (SREBP-1c) and its target genes acetyl-CoA carboxylase (ACC) and fatty acid synthase (FAS) involved in lipogenesis. Peroxisome proliferator-activated receptor α (PPARα) and its target gene carnitine palmitoyltransferase-1 (CPT-1) involved in hepatic fatty acid (FA) oxidation were upregulated by 1,25(OH)(2) D(3) . CONCLUSIONS These results suggest that the preventing effect of 1,25(OH)(2) D(3) against HFD-induced hepatic steatosis is related to the inhibition of lipogenesis and the promotion of FA oxidation in rat liver.
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Affiliation(s)
- Yi Yin
- Guangdong Provincial Key Laboratory of Food, Nutrition and Health, Department of Nutrition, School of Public Health, Sun Yat-sen University, Guangzhou, China
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Bruce KD, Sihota KK, Byrne CD, Cagampang FR. The housekeeping gene YWHAZ remains stable in a model of developmentally primed non-alcoholic fatty liver disease. Liver Int 2012; 32:1315-21. [PMID: 22583519 DOI: 10.1111/j.1478-3231.2012.02813.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/29/2011] [Accepted: 04/03/2012] [Indexed: 12/12/2022]
Abstract
BACKGROUND Non-alcoholic fatty liver disease (NAFLD) is the most common form of chronic liver disease in Western society. Comparative gene expression studies are beginning to elucidate the molecular mechanisms underlying NAFLD progression. We have previously shown that high fat diets during early life can prime non-alcoholic steatohepatitis (NASH) in adulthood, through lipogenesis gene elevation. To generate accurate results in such studies, appropriate housekeeping genes (HKG) which are unaffected by disease processes, are used for data normalisation. However, there is little existing data to show the effects of NAFLD on HKG expression. AIMS To identify the HKG in a mouse model of developmentally primed NAFLD and NASH, which maintains expression stability. METHODS We determined the expression stability of six candidates HKG (GAPDH, YWHAZ, B2M, EIF4A2, ACTB and CYC1) in a mouse model of developmentally primed NAFLD in both the day and night, using geNORM qBasePlus software. RESULTS HKG expression differed across dietary groups and time of day. In the majority of treatment groups and time points the most stable gene was YWHAZ. Following high fat diet interventions CYC1 became notably unstable. Overall the effect of NAFLD and NASH on HKG expression was to maintain stability of YWHAZ, but destabilise CYC1 and EIF4A2. CONCLUSIONS Our data clearly shows that HKG expression is affected by NAFLD severity and time of day sampling, highlighting the importance of suitable HKG gene selection. For comparative gene expression studies investigating NAFLD we would recommend use of YWHAZ as a robust, stably expressed HKG.
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Affiliation(s)
- Kimberley D Bruce
- Human Development and Health, Institute of Developmental Sciences, University of Southampton Faculty of Medicine, Southampton, UK.
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Cha JY, Kim YB. Sulfated oxysterol 25HC3S as a therapeutic target of non-alcoholic fatty liver disease. Metabolism 2012; 61:1055-7. [PMID: 22592130 DOI: 10.1016/j.metabol.2012.04.011] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/04/2012] [Revised: 04/11/2012] [Accepted: 04/11/2012] [Indexed: 11/21/2022]
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Kuo JJ, Chang HH, Tsai TH, Lee TY. Positive effect of curcumin on inflammation and mitochondrial dysfunction in obese mice with liver steatosis. Int J Mol Med 2012; 30:673-9. [PMID: 22751848 DOI: 10.3892/ijmm.2012.1049] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2012] [Accepted: 06/08/2012] [Indexed: 12/19/2022] Open
Abstract
Obesity contributes to the increased risk of liver- related morbidity and mortality. The accumulation of macrophages in adipose tissue in an inflammatory state is a hallmark of obesity-induced hepatic steatosis. In this study, we reveal the role of curcumin in the molecular mechanisms underlying inflammatory events in a model consisting of obese mice with hepatic steatosis. Obese mice fed with curcumin experienced significant weight loss and significantly reduced serum triglyceride (TG) levels. The adipose tumor necrocis factor-α, interleukin-6 (IL-6) and monocyte chemotactic protein-1 levels were significantly higher in obese mice compared to mice fed with curcumin. Compared to the obese mice, curcumin decreased the number of F4/80-positive macrophages in epididymal adipose and liver tissue. The induction of signal transducer and activator of transcription 3 phosphorylation by curcumin resulted in the downregulation of the suppressor of cytokine signaling 3 in the liver of obese mice. Curcumin decreased hepatic TG in obese mice by downregulating the gene expression of sterol regulatory element-binding protein-1c in the liver. The hepatic expression of several mitochondrial biogenesis genes decreased in the obese mice, including mitochondrial DNA (mtDNA), nuclear respiratory factor 1 (NRF1) and mitochondrial transcription factor A (Tfam), which are responsible for the lower mitochondrial respiratory chain (MRC) complex I activity and adenosine triphosphate production. By contrast, obese mice treated with curcumin showed normalized mtDNA, NRF1 and Tfam gene expression, reduced hepatic nuclear factor-κB activities and levels of thiobarbituric acid reactive substances (TBARS) and restored mitochondrial oxidative metabolism and biogenesis. The results from the present sudy show that curcumin prevents fatty liver disease through multiple mechanisms, and suggest that curcumin may be used to prevent the development and progression of non-alcoholic fatty liver disease (NAFLD).
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Affiliation(s)
- Jong-Jen Kuo
- Institute of Traditional Medicine, National Yang Ming University, Taipei, Taiwan, R.O.C
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Cusi K. Role of obesity and lipotoxicity in the development of nonalcoholic steatohepatitis: pathophysiology and clinical implications. Gastroenterology 2012; 142:711-725.e6. [PMID: 22326434 DOI: 10.1053/j.gastro.2012.02.003] [Citation(s) in RCA: 620] [Impact Index Per Article: 51.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/26/2011] [Revised: 01/04/2012] [Accepted: 02/02/2012] [Indexed: 02/07/2023]
Abstract
As obesity reaches epidemic proportions, nonalcoholic fatty liver disease (NAFLD) is becoming a frequent cause of patient referral to gastroenterologists. There is a close link between dysfunctional adipose tissue in NAFLD and common conditions such as metabolic syndrome, type 2 diabetes mellitus, and cardiovascular disease. This review focuses on the pathophysiology of interactions between adipose tissue and target organs in obesity and the resulting clinical implications for the management of nonalcoholic steatohepatitis. The release of fatty acids from dysfunctional and insulin-resistant adipocytes results in lipotoxicity, caused by the accumulation of triglyceride-derived toxic metabolites in ectopic tissues (liver, muscle, pancreatic beta cells) and subsequent activation of inflammatory pathways, cellular dysfunction, and lipoapoptosis. The cross talk between dysfunctional adipocytes and the liver involves multiple cell populations, including macrophages and other immune cells, that in concert promote the development of lipotoxic liver disease, a term that more accurately describes the pathophysiology of nonalcoholic steatohepatitis. At the clinical level, adipose tissue insulin resistance contributes to type 2 diabetes mellitus and cardiovascular disease. Treatments that rescue the liver from lipotoxicity by restoring adipose tissue insulin sensitivity (eg, significant weight loss, exercise, thiazolidinediones) or preventing activation of inflammatory pathways and oxidative stress (ie, vitamin E, thiazolidinediones) hold promise in the treatment of NAFLD, although their long-term safety and efficacy remain to be established. Better understanding of pathways that link dysregulated adipose tissue, metabolic dysfunction, and liver lipotoxicity will result in improvements in the clinical management of these challenging patients.
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Affiliation(s)
- Kenneth Cusi
- Division of Endocrinology, Diabetes and Metabolism, University of Florida, Gainesville, Florida 32610-0226, USA.
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Rolo AP, Teodoro JS, Palmeira CM. Role of oxidative stress in the pathogenesis of nonalcoholic steatohepatitis. Free Radic Biol Med 2012; 52:59-69. [PMID: 22064361 DOI: 10.1016/j.freeradbiomed.2011.10.003] [Citation(s) in RCA: 674] [Impact Index Per Article: 56.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/28/2011] [Revised: 10/03/2011] [Accepted: 10/04/2011] [Indexed: 02/07/2023]
Abstract
The worldwide rising prevalence of obesity and insulin resistance is associated with a parallel increase in nonalcoholic fatty liver disease (NAFLD). NAFLD is characterized by excess accumulation of triglyceride in the hepatocyte due to increased inflow of free fatty acids and/or de novo lipogenesis caused by various drugs and multiple defects in energy metabolism. Accumulation of lipids in the hepatocyte impairs the oxidative capacity of the mitochondria, increasing the reduced state of the electron transport chain (ETC) complexes and stimulating peroxisomal and microsomal pathways of fat oxidation. The consequent increased generation of reactive oxygen species (ROS) and reactive aldehydic derivatives causes oxidative stress and cell death, via ATP, NAD, and glutathione depletion and DNA, lipid, and protein damage. Oxidative stress also triggers production of inflammatory cytokines, causing inflammation and a fibrogenic response. This ultimately results in the development of nonalcoholic steatohepatitis (NASH), which can result in end-stage liver disease. The current therapeutic strategies for NASH treatment are mostly directed toward correction of the risk factors. Stimulation of mitochondrial function may also prevent NASH development, protecting the cell against the increased flux of reduced substrates to the ETC and ROS generation.
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Affiliation(s)
- Anabela P Rolo
- Center for Neuroscience and Cell Biology, Faculty of Science and Technology, University of Coimbra, Coimbra, Portugal
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Xia Y, Li Q, Zhong W, Dong J, Wang Z, Wang C. L-carnitine ameliorated fatty liver in high-calorie diet/STZ-induced type 2 diabetic mice by improving mitochondrial function. Diabetol Metab Syndr 2011; 3:31. [PMID: 22082204 PMCID: PMC3226540 DOI: 10.1186/1758-5996-3-31] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/22/2011] [Accepted: 11/15/2011] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND There are an increasing number of patients suffering from fatty liver caused by type 2 diabetes. We intended to study the preventive and therapeutic effect of L-carnitine (LC) on nonalcoholic fatty liver disease (NAFLD) in streptozotocin (STZ)-induced type 2 diabetic mice and to explore its possible mechanism. METHODS Thirty male Kungming mice were randomly divided into five groups: control group, diabetic group, pre-treatment group (125 mg/kg BW), low-dose (125 mg/kg BW) therapeutic group and high-dose (250 mg/kg BW) therapeutic group. The morphology of hepatocytes was observed by light and electron microscopy. LC and ALC (acetyl L-carnitine) concentrations in the liver were determined by high-performance liquid chromatography (HPLC). Moreover, liver weight, insulin levels and free fatty acid (FFA) and triglyceride (TG) levels in the liver and plasma were measured. RESULTS Average liver LC and ALC levels were 33.7% and 20% lower, respectively, in diabetic mice compared to control mice (P < 0.05). After preventive and therapeutic treatment with LC, less hepatocyte steatosis, clearer crista and fewer glycogen granules in the mitochondria were observed. Decreased liver weight, TG levels, and FFA concentrations (P < 0.05) in the liver were also observed after treatment with LC in diabetic mice. Moreover, liver LC and ALC levels increased upon treatment with LC, whereas the ratio of LC and ALC decreased significantly (P < 0.01). CONCLUSION LC supplements ameliorated fatty liver in type 2 diabetic mice by increasing fatty acid oxidation and decreasing the LC/ALC ratio in the liver. Therefore, oral administration of LC protected mitochondrial function in liver.
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Affiliation(s)
- Yunqiu Xia
- Center for Human Functional Experiment, Medical College, Qingdao University, Ningxia Road, Qingdao, China
| | - Qing Li
- Class 5, Grade 2007, Medical College, Qingdao University, Ningxia Road, Qingdao, China
| | - Weizhen Zhong
- Center for Human Functional Experiment, Medical College, Qingdao University, Ningxia Road, Qingdao, China
| | - Jing Dong
- Physiology Department of the Medical College, Qingdao University, Ningxia Road, Qingdao, China
| | - Zhulin Wang
- Class 5, Grade 2007, Medical College, Qingdao University, Ningxia Road, Qingdao, China
| | - Chunbo Wang
- Center for Human Functional Experiment, Medical College, Qingdao University, Ningxia Road, Qingdao, China
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Wenz T. Mitochondria and PGC-1α in Aging and Age-Associated Diseases. J Aging Res 2011; 2011:810619. [PMID: 21629705 PMCID: PMC3100651 DOI: 10.4061/2011/810619] [Citation(s) in RCA: 86] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2010] [Revised: 02/23/2011] [Accepted: 02/24/2011] [Indexed: 12/31/2022] Open
Abstract
Aging is the most significant risk factor for a range of degenerative disease such as cardiovascular, neurodegenerative and metabolic disorders. While the cause of aging and its associated diseases is multifactorial, mitochondrial dysfunction has been implicated in the aging process and the onset and progression of age-associated disorders. Recent studies indicate that maintenance of mitochondrial function is beneficial in the prevention or delay of age-associated diseases. A central molecule seems to be the peroxisome proliferator-activated receptor γ coactivator α (PGC-1α), which is the key regulator of mitochondrial biogenesis. Besides regulating mitochondrial function, PGC-1α targets several other cellular processes and thereby influences cell fate on multiple levels. This paper discusses how mitochondrial function and PGC-1α are affected in age-associated diseases and how modulation of PGC-1α might offer a therapeutic potential for age-related pathology.
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Affiliation(s)
- Tina Wenz
- Institute for Genetics, Cluster of Excellence, Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, Zülpicher Straße 47A, 50674 Cologne, Germany
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