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Alogaili F, Chinnarasu S, Jaeschke A, Kranias EG, Hui DY. Hepatic HAX-1 inactivation prevents metabolic diseases by enhancing mitochondrial activity and bile salt export. J Biol Chem 2020; 295:4631-4646. [PMID: 32079675 DOI: 10.1074/jbc.ra119.012361] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2019] [Revised: 02/04/2020] [Indexed: 12/26/2022] Open
Abstract
Increasing hepatic mitochondrial activity through pyruvate dehydrogenase and elevating enterohepatic bile acid recirculation are promising new approaches for metabolic disease therapy, but neither approach alone can completely ameliorate disease phenotype in high-fat diet-fed mice. This study showed that diet-induced hepatosteatosis, hyperlipidemia, and insulin resistance can be completely prevented in mice with liver-specific HCLS1-associated protein X-1 (HAX-1) inactivation. Mechanistically, we showed that HAX-1 interacts with inositol 1,4,5-trisphosphate receptor-1 (InsP3R1) in the liver, and its absence reduces InsP3R1 levels, thereby improving endoplasmic reticulum-mitochondria calcium homeostasis to prevent excess calcium overload and mitochondrial dysfunction. As a result, HAX-1 ablation activates pyruvate dehydrogenase and increases mitochondria utilization of glucose and fatty acids to prevent hepatosteatosis, hyperlipidemia, and insulin resistance. In contrast to the reduction of InsP3R1 levels, hepatic HAX-1 deficiency increases bile salt exporter protein levels, thereby promoting enterohepatic bile acid recirculation, leading to activation of bile acid-responsive genes in the intestinal ileum to augment insulin sensitivity and of cholesterol transport genes in the liver to suppress hyperlipidemia. The dual mechanisms of increased mitochondrial respiration and enterohepatic bile acid recirculation due to improvement of endoplasmic reticulum-mitochondria calcium homeostasis with hepatic HAX-1 inactivation suggest that this may be a potential therapeutic target for metabolic disease intervention.
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Affiliation(s)
- Fawzi Alogaili
- Department of Pathology and Laboratory Medicine, Metabolic Diseases Research Center, University of Cincinnati College of Medicine, Cincinnati, Ohio 45237.,Department of Pharmacology and Systems Physiology, University of Cincinnati College of Medicine, Cincinnati, Ohio 45267
| | - Sivaprakasam Chinnarasu
- Department of Pathology and Laboratory Medicine, Metabolic Diseases Research Center, University of Cincinnati College of Medicine, Cincinnati, Ohio 45237
| | - Anja Jaeschke
- Department of Pathology and Laboratory Medicine, Metabolic Diseases Research Center, University of Cincinnati College of Medicine, Cincinnati, Ohio 45237
| | - Evangelia G Kranias
- Department of Pharmacology and Systems Physiology, University of Cincinnati College of Medicine, Cincinnati, Ohio 45267
| | - David Y Hui
- Department of Pathology and Laboratory Medicine, Metabolic Diseases Research Center, University of Cincinnati College of Medicine, Cincinnati, Ohio 45237
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52
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Laitano O, Garcia CK, Mattingly AJ, Robinson GP, Murray KO, King MA, Ingram B, Ramamoorthy S, Leon LR, Clanton TL. Delayed metabolic dysfunction in myocardium following exertional heat stroke in mice. J Physiol 2020; 598:967-985. [PMID: 32026469 DOI: 10.1113/jp279310] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2019] [Accepted: 01/15/2020] [Indexed: 12/20/2022] Open
Abstract
KEY POINTS Exposure to exertional heat stroke (EHS) is associated with increased risk of long-term cardiovascular disorders in humans. We demonstrate that in female mice, severe EHS results in metabolic changes in the myocardium, emerging only after 9-14 days. This was not observed in males that were symptom-limited at much lower exercise levels and heat loads compared to females. At 14 days of recovery in females, there were marked elevations in myocardial free fatty acids, ceramides and diacylglycerols, consistent with development of underlying cardiac abnormalities. Glycolysis shifted towards the pentose phosphate and glycerol-3-phosphate dehydrogenase pathways. There was evidence for oxidative stress, tissue injury and microscopic interstitial inflammation. The tricarboxylic acid cycle and nucleic acid metabolism pathways were also negatively affected. We conclude that exposure to EHS in female mice has the capacity to cause delayed metabolic disorders in the heart that could influence long-term health. ABSTRACT Exposure to exertional heat stroke (EHS) is associated with a higher risk of long-term cardiovascular disease in humans. Whether this is a cause-and-effect relationship remains unknown. We studied the potential of EHS to contribute to the development of a 'silent' form of cardiovascular disease using a preclinical mouse model of EHS. Plasma and ventricular myocardial samples were collected over 14 days of recovery. Male and female C57bl/6J mice underwent forced wheel running for 1.5-3 h in a 37.5°C/40% relative humidity until symptom limitation, characterized by CNS dysfunction. They reached peak core temperatures of 42.2 ± 0.3°C. Females ran ∼40% longer, reaching ∼51% greater heat load. Myocardial and plasma samples (n = 8 per group) were obtained between 30 min and 14 days of recovery, analysed using metabolomics/lipidomics platforms and compared to exercise controls. The immediate recovery period revealed an acute energy substrate crisis from which both sexes recovered within 24 h. However, at 9-14 days, the myocardium of female mice developed marked elevations in free fatty acids, ceramides and diacylglycerols. Glycolytic and tricarboxylic acid cycle metabolites revealed bottlenecks in substrate flow, with build-up of intermediate metabolites consistent with oxidative stress and damage. Males exhibited only late stage reductions in acylcarnitines and elevations in acetylcarnitine. Histopathology at 14 days showed interstitial inflammation in the female hearts only. The results demonstrate that the myocardium of female mice is vulnerable to a slowly emerging metabolic disorder following EHS that may harbinger long-term cardiovascular complications. Lack of similar findings in males may reflect their lower heat exposure.
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Affiliation(s)
- Orlando Laitano
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, FL, USA
| | - Christian K Garcia
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, FL, USA
| | - Alex J Mattingly
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, FL, USA
| | - Gerard P Robinson
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, FL, USA
| | - Kevin O Murray
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, FL, USA
| | - Michelle A King
- US Army Research Institute for Environmental Medicine, Natick, MA, USA
| | | | | | - Lisa R Leon
- US Army Research Institute for Environmental Medicine, Natick, MA, USA
| | - Thomas L Clanton
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, FL, USA
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53
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da Silva DC, Valentão P, Andrade PB, Pereira DM. Endoplasmic reticulum stress signaling in cancer and neurodegenerative disorders: Tools and strategies to understand its complexity. Pharmacol Res 2020; 155:104702. [PMID: 32068119 DOI: 10.1016/j.phrs.2020.104702] [Citation(s) in RCA: 45] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Revised: 02/10/2020] [Accepted: 02/13/2020] [Indexed: 12/12/2022]
Abstract
The endoplasmic reticulum (ER) comprises a network of tubules and vesicles that constitutes the largest organelle of the eukaryotic cell. Being the location where most proteins are synthesized and folded, it is crucial for the upkeep of cellular homeostasis. Disturbed ER homeostasis triggers the activation of a conserved molecular machinery, termed the unfolded protein response (UPR), that comprises three major signaling branches, initiated by the protein kinase RNA-like endoplasmic reticulum kinase (PERK), inositol-requiring enzyme 1 (IRE1) and the activating transcription factor 6 (ATF6). Given the impact of this intricate signaling network upon an extensive list of cellular processes, including protein turnover and autophagy, ER stress is involved in the onset and progression of multiple diseases, including cancer and neurodegenerative disorders. There is, for this reason, an increasing number of publications focused on characterizing and/or modulating ER stress, which have resulted in a wide array of techniques employed to study ER-related molecular events. This review aims to sum up the essentials on the current knowledge of the molecular biology of endoplasmic reticulum stress, while highlighting the available tools used in studies of this nature.
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Affiliation(s)
- Daniela Correia da Silva
- REQUIMTE/LAQV, Laboratório de Farmacognosia, Departamento de Química, Faculdade de Farmácia, Universidade do Porto, Rua de Jorge Viterbo Ferreira, 228, 4050-213, Porto, Portugal
| | - Patrícia Valentão
- REQUIMTE/LAQV, Laboratório de Farmacognosia, Departamento de Química, Faculdade de Farmácia, Universidade do Porto, Rua de Jorge Viterbo Ferreira, 228, 4050-213, Porto, Portugal
| | - Paula B Andrade
- REQUIMTE/LAQV, Laboratório de Farmacognosia, Departamento de Química, Faculdade de Farmácia, Universidade do Porto, Rua de Jorge Viterbo Ferreira, 228, 4050-213, Porto, Portugal
| | - David M Pereira
- REQUIMTE/LAQV, Laboratório de Farmacognosia, Departamento de Química, Faculdade de Farmácia, Universidade do Porto, Rua de Jorge Viterbo Ferreira, 228, 4050-213, Porto, Portugal.
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54
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Yang W, Liu R, Xia C, Chen Y, Dong Z, Huang B, Li R, Li M, Xu C. Effects of different fatty acids on BRL3A rat liver cell damage. J Cell Physiol 2020; 235:6246-6256. [PMID: 32012270 DOI: 10.1002/jcp.29553] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2018] [Accepted: 01/10/2020] [Indexed: 12/15/2022]
Abstract
To evaluate the effects of fatty acids on endoplasmic reticulum (ER) stress, oxidative stress, and lipid damage. We treated BRL3A rat liver cells with, linoleic (LA), linolenic, oleic (OA), palmitic (PA), palmitoleic (POA), or stearic (SA) acid for 12 hr. The characteristics of cell lipid deposition, oxidative stress indexes, ER stress markers, nuclear factor κB p65 (NF-κB p65), lipid synthesis and transport regulators, and cholesterol metabolism regulators were analyzed. Endoplasmic chaperones like glucose-regulated protein 78, CCAAT-enhancer-binding protein, NF-κB p65, hydrogen peroxide, and malonaldehyde in PA- and SA-treated cells were significantly higher than in other treated cells. Deposition of fatty acids especially LA and POA were significantly increased than in other treated cells. De novo lipogenesis regulators sterol regulatory element-binding protein 1c, fatty acid synthase, and acetyl-coenzyme A carboxylase 1 (ACC1) expression were significantly increased in all fatty acid stimulation groups, and PA- and SA-treated cells showed lower p-ACC1 expression and higher scd1 expression than other fatty acid groups. Very low-density lipoprotein synthesis and apolipoprotein B100 expression in free fatty acids treated cells were significantly lower than control. PA, SA, OA, and POA had shown significantly increased cholesterol synthesis than other treated cells. PA and SA showed the lower synthesis of cytochrome P7A1 and total bile acids than other fatty acids treated cells. Excess of saturated fatty acids led to severe ER and oxidative stress. Excess unsaturated fatty acids led to increased lipid deposition in cultured hepatocytes. A balanced fatty acid intake is needed to maintain lipid homeostasis.
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Affiliation(s)
- Wei Yang
- Clinical Veterinary Medicine, College of Animal Science and Veterinary Medicine, Heilongjiang Bayi Agricultural University, Daqing, China
| | - Runqi Liu
- Clinical Veterinary Medicine, College of Animal Science and Veterinary Medicine, Heilongjiang Bayi Agricultural University, Daqing, China
| | - Cheng Xia
- Clinical Veterinary Medicine, College of Animal Science and Veterinary Medicine, Heilongjiang Bayi Agricultural University, Daqing, China
| | - Yuanyuan Chen
- Clinical Veterinary Medicine, College of Animal Science and Veterinary Medicine, Heilongjiang Bayi Agricultural University, Daqing, China
| | - Zhihao Dong
- Clinical Veterinary Medicine, College of Animal Science and Veterinary Medicine, Heilongjiang Bayi Agricultural University, Daqing, China
| | - Baoyin Huang
- Clinical Veterinary Medicine, College of Animal Science and Veterinary Medicine, Heilongjiang Bayi Agricultural University, Daqing, China
| | - Ruirui Li
- Clinical Veterinary Medicine, College of Animal Science and Veterinary Medicine, Heilongjiang Bayi Agricultural University, Daqing, China
| | - Ming Li
- Clinical Veterinary Medicine, College of Animal Science and Veterinary Medicine, Heilongjiang Bayi Agricultural University, Daqing, China
| | - Chuang Xu
- Clinical Veterinary Medicine, College of Animal Science and Veterinary Medicine, Heilongjiang Bayi Agricultural University, Daqing, China
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55
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Liu L, Xie B, Fan M, Candas-Green D, Jiang JX, Wei R, Wang Y, Chen HW, Hu Y, Li JJ. Low-Level Saturated Fatty Acid Palmitate Benefits Liver Cells by Boosting Mitochondrial Metabolism via CDK1-SIRT3-CPT2 Cascade. Dev Cell 2019; 52:196-209.e9. [PMID: 31866205 DOI: 10.1016/j.devcel.2019.11.012] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2018] [Revised: 10/10/2019] [Accepted: 11/18/2019] [Indexed: 12/20/2022]
Abstract
Saturated fatty acids (SFAs) (the "bad" fat), especially palmitate (PA), in the human diet are blamed for potential health risks such as obesity and cancer because of SFA-induced lipotoxicity. However, epidemiological results demonstrate a latent benefit of SFAs, and it remains elusive whether a certain low level of SFAs is physiologically essential for maintaining cell metabolic hemostasis. Here, we demonstrate that although high-level PA (HPA) indeed induces lipotoxic effects in liver cells, low-level PA (LPA) increases mitochondrial functions and alleviates the injuries induced by HPA or hepatoxic agent carbon tetrachloride (CCl4). LPA treatment in mice enhanced liver mitochondrial activity and reduced CCl4 hepatotoxicity with improved blood levels of aspartate aminotransferase (AST), alanine transaminase (ALT), and mitochondrial aspartate transaminase (m-AST). LPA-mediated mitochondrial homeostasis is regulated by CDK1-mediated SIRT3 phosphorylation, which in turn deacetylates and dimerizes CPT2 to enhance fatty acid oxidation. Thus, an advantageous effect is suggested by the consumption of LPA that augments mitochondrial metabolic homeostasis via CDK1-SIRT3-CPT2 cascade.
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Affiliation(s)
- Lin Liu
- Department of Radiation Oncology, School of Medicine, University of California, Davis, Sacramento, CA, USA; Institute of Liver Diseases, Shuguan Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Bowen Xie
- Department of Radiation Oncology, School of Medicine, University of California, Davis, Sacramento, CA, USA
| | - Ming Fan
- Department of Radiation Oncology, School of Medicine, University of California, Davis, Sacramento, CA, USA
| | - Demet Candas-Green
- Department of Radiation Oncology, School of Medicine, University of California, Davis, Sacramento, CA, USA
| | - Joy X Jiang
- Department of Internal Medicine, Division of Gastroenterology and Hepatology, School of Medicine, University of California, Davis, Sacramento, CA, USA
| | - Ryan Wei
- Department of Radiation Oncology, School of Medicine, University of California, Davis, Sacramento, CA, USA; Lewis Katz School of Medicine, Temple University, Philadelphia, PA, USA
| | - Yinsheng Wang
- Department of Chemistry, University of California, Riverside, Riverside, CA, USA
| | - Hong-Wu Chen
- Department of Biochemistry and Molecular Medicine, School of Medicine, University of California, Davis, Sacramento, CA, USA; Comprehensive Cancer Center, University of California, Davis, Sacramento, CA, USA
| | - Yiyang Hu
- Institute of Liver Diseases, Shuguan Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Jian Jian Li
- Department of Radiation Oncology, School of Medicine, University of California, Davis, Sacramento, CA, USA; Comprehensive Cancer Center, University of California, Davis, Sacramento, CA, USA.
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56
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Sodium fluorocitrate having inhibitory effect on fatty acid uptake ameliorates high fat diet-induced non-alcoholic fatty liver disease in C57BL/6J mice. Sci Rep 2019; 9:17839. [PMID: 31780766 PMCID: PMC6882787 DOI: 10.1038/s41598-019-54476-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2019] [Accepted: 11/13/2019] [Indexed: 12/30/2022] Open
Abstract
Non-alcoholic fatty liver disease (NAFLD) is excessive fat build-up in the liver without alcohol consumption and includes hepatic inflammation and damage. Excessive influx of fatty acids to liver from circulation is thought to be a pathogenic cause for the development of NAFLD. Thus, inhibition of fatty acid intake into hepatocyte would be a maneuver for protection from high fat diet (HFD)-induced NAFLD. This study was initiated to determine whether sodium fluorocitrate (SFC) as a fatty acid uptake inhibitor could prevent palmitate-induced lipotoxicity in hepatocytes and protect the mice from HFD-induced NAFLD. SFC significantly inhibited the cellular uptake of palmitate in HepG2 hepatocytes, and thus prevented palmitate-induced fat accumulation and death in these cells. Single treatment with SFC reduced fasting-induced hepatic steatosis in C57BL/6J mice. Concurrent treatment with SFC for 15 weeks in HFD-fed C57BL/6J mice prevented HFD-induced fat accumulation and stress/inflammatory signal activation in the liver. SFC restored HFD-induced increased levels of serum alanine aminotransferase and aspartate aminotransferases as hepatic injury markers in these mice. SFC treatment also improved HFD-induced hepatic insulin resistance, and thus ameliorated HFD-induced hyperglycemia. In conclusion, inhibition of fatty acid mobilization into liver through SFC treatment can be a strategy to protect from HFD-induced NAFLD.
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57
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Svegliati-Baroni G, Pierantonelli I, Torquato P, Marinelli R, Ferreri C, Chatgilialoglu C, Bartolini D, Galli F. Lipidomic biomarkers and mechanisms of lipotoxicity in non-alcoholic fatty liver disease. Free Radic Biol Med 2019; 144:293-309. [PMID: 31152791 DOI: 10.1016/j.freeradbiomed.2019.05.029] [Citation(s) in RCA: 132] [Impact Index Per Article: 26.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/24/2019] [Revised: 05/13/2019] [Accepted: 05/27/2019] [Indexed: 02/06/2023]
Abstract
Non-alcoholic fatty liver disease (NAFLD) represents the most common form of chronic liver disease worldwide (about 25% of the general population) and 3-5% of patients develop non-alcoholic steatohepatitis (NASH), characterized by hepatocytes damage, inflammation and fibrosis, which increase the risk of developing liver failure, cirrhosis and hepatocellular carcinoma. The pathogenesis of NAFLD, particularly the mechanisms whereby a minority of patients develop a more severe phenotype, is still incompletely understood. In this review we examine the available literature on initial mechanisms of hepatocellular damage and inflammation, deriving from toxic effects of excess lipids. Accumulating data indicate that the total amount of triglycerides stored in the liver cells is not the main determinant of lipotoxicity and that specific lipid classes act as damaging agents. These lipotoxic species affect the cell behavior via multiple mechanisms, including activation of death receptors, endoplasmic reticulum stress, modification of mitochondrial function and oxidative stress. The gut microbiota, which provides signals through the intestine to the liver, is also reported to play a key role in lipotoxicity. Finally, we summarize the most recent lipidomic strategies utilized to explore the liver lipidome and its modifications in the course of NALFD. These include measures of lipid profiles in blood plasma and erythrocyte membranes that can surrogate to some extent lipid investigation in the liver.
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Affiliation(s)
- Gianluca Svegliati-Baroni
- Department of Gastroenterology, Università Politecnica Delle Marche, Ancona, Italy; Obesity Center, Università Politecnica Delle Marche, Ancona, Italy.
| | - Irene Pierantonelli
- Department of Gastroenterology, Università Politecnica Delle Marche, Ancona, Italy; Department of Gastroenterology, Senigallia Hospital, Senigallia, Italy
| | | | - Rita Marinelli
- Department of Pharmaceutical Sciences, University of Perugia, Italy
| | - Carla Ferreri
- ISOF, Consiglio Nazionale Delle Ricerche, Via P. Gobetti 101, 40129, Bologna, Italy
| | | | | | - Francesco Galli
- Department of Pharmaceutical Sciences, University of Perugia, Italy
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58
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Diao X, Zhou Z, Xiang W, Jiang Y, Tian N, Tang X, Chen S, Wen J, Chen M, Liu K, Li Q, Liao R. Glutathione alleviates acute intracerebral hemorrhage injury via reversing mitochondrial dysfunction. Brain Res 2019; 1727:146514. [PMID: 31628933 DOI: 10.1016/j.brainres.2019.146514] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2019] [Revised: 10/02/2019] [Accepted: 10/16/2019] [Indexed: 01/01/2023]
Abstract
Glutathione (GSH) has been studied for its neuroprotection value in several diseases, but the effect of GSH on intracerebral hemorrhage (ICH) is unclear. In this study, we examined the protective effects of GSH in an experimentally induced ICH model and investigated the relative mechanisms. Adult male C57BL/6j mice were randomized into Sham, ICH and GSH treatment groups. GSH was injected with the dose of 50, 100 or 200 mg/kg once per day for 3 days, starting immediately after operation. The results revealed a GSH-mediated improvement of neurological deficits score (NDS), motor and sensory functions impairment in a dose-dependent manner three days post ICH (p < 0.01, GSH 200 vs ICH. Sham, n = 12; ICH, n = 9; GSH 50, n = 10; GSH 100, n = 10; GSH 200, n = 11) in addition to significantly reduced mortality rate (p = 0.2632, GSH 200 vs ICH. n = 12 per group) and damage volume (p < 0.05, GSH 200 vs ICH. n = 12 per group). GSH treatment also attenuated injury measured by decreased brain edema (p < 0.05, GSH 200 vs ICH. Sham, n = 10; ICH, n = 10; GSH 200, n = 12), blood-brain barrier disruption (p < 0.05, GSH 200 vs ICH. Sham, n = 10; ICH, n = 10; GSH 200, n = 12), and histopathological damage (p < 0.05, GSH 200 vs ICH. Sham, n = 6; ICH, n = 6; GSH 200, n = 8) 72 h after ICH. In addition, GSH treatment also decreased cell apoptosis (p < 0.01, GSH 200 vs ICH. Sham, n = 6; ICH, n = 6; GSH 200, n = 8) and resulted in up-regulated protein expression of complex I (p < 0.01, GSH 200 vs ICH. Sham, n = 6; ICH, n = 6; GSH 200, n = 8), which was consistent with an overall up-regulation of complex I function in mitochondria using Oxygraph-2 K high resolution respirometry (p < 0.05, GSH 200 vs ICH. Sham, n = 4; ICH, n = 5; GSH 200, n = 6). In conclusion, GSH effectively improved the prognosis of ICH mice by attenuating neurological impairment, decreasing neural damage, and inhibiting apoptosis. The neuroprotection by GSH resulted from the up-regulation of mitochondrial oxidative respiration function. The results of our study suggest that GSH can be a potential therapeutic agent for ICH.
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Affiliation(s)
- Xiaojun Diao
- Department of Neurology, Xiangya Hospital, Central South University, Changsha 410000, China; Guilin Medical University, Guilin 541004, China
| | - Zixian Zhou
- Department of Neurology, Affiliated Hospital of Guilin Medical University, Guilin Medical University, Guilin 541004, China; Laboratory of Neuroscience, Affiliated Hospital of Guilin Medical University, Guilin Medical University, Guilin 541004, China
| | - Wenjing Xiang
- Department of Neurology, Affiliated Hospital of Guilin Medical University, Guilin Medical University, Guilin 541004, China; Laboratory of Neuroscience, Affiliated Hospital of Guilin Medical University, Guilin Medical University, Guilin 541004, China
| | - Yanlin Jiang
- Department of Pharmacology, Affiliated Hospital of Guilin Medical University, Guilin Medical University, Guilin 541004, China
| | - Ning Tian
- Laboratory of Neuroscience, Affiliated Hospital of Guilin Medical University, Guilin Medical University, Guilin 541004, China; Guangxi Clinical Research Center for Neurological Diseases, Affiliated Hospital of Guilin Medical University, Guilin Medical University, Guilin 541004, China; Guangxi Key Laboratory of Brain and Cognitive Neuroscience, Guilin Medical University, Guilin 541004, China
| | - Xiaoling Tang
- Department of Neurology, Affiliated Hospital of Guilin Medical University, Guilin Medical University, Guilin 541004, China
| | - Sangsang Chen
- Department of Neurology, Affiliated Hospital of Guilin Medical University, Guilin Medical University, Guilin 541004, China
| | - Jian Wen
- Guangxi Clinical Research Center for Neurological Diseases, Affiliated Hospital of Guilin Medical University, Guilin Medical University, Guilin 541004, China; Guangxi Key Laboratory of Brain and Cognitive Neuroscience, Guilin Medical University, Guilin 541004, China
| | - Meiling Chen
- Department of Neurology, Affiliated Hospital of Guilin Medical University, Guilin Medical University, Guilin 541004, China
| | - Kaixiang Liu
- Department of Neurology, Affiliated Hospital of Guilin Medical University, Guilin Medical University, Guilin 541004, China
| | - Qinghua Li
- Department of Neurology, Xiangya Hospital, Central South University, Changsha 410000, China; Department of Neurology, Affiliated Hospital of Guilin Medical University, Guilin Medical University, Guilin 541004, China; Laboratory of Neuroscience, Affiliated Hospital of Guilin Medical University, Guilin Medical University, Guilin 541004, China; Guangxi Clinical Research Center for Neurological Diseases, Affiliated Hospital of Guilin Medical University, Guilin Medical University, Guilin 541004, China; Guangxi Key Laboratory of Brain and Cognitive Neuroscience, Guilin Medical University, Guilin 541004, China.
| | - Rujia Liao
- Department of Neurology, Affiliated Hospital of Guilin Medical University, Guilin Medical University, Guilin 541004, China; Laboratory of Neuroscience, Affiliated Hospital of Guilin Medical University, Guilin Medical University, Guilin 541004, China; Guangxi Clinical Research Center for Neurological Diseases, Affiliated Hospital of Guilin Medical University, Guilin Medical University, Guilin 541004, China; Guangxi Key Laboratory of Brain and Cognitive Neuroscience, Guilin Medical University, Guilin 541004, China.
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59
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Zámbó V, Simon-Szabó L, Sarnyai F, Mátyási J, Gór-Nagy Z, Somogyi A, Szelényi P, Kereszturi É, Tóth B, Csala M. Investigation of the putative rate-limiting role of electron transfer in fatty acid desaturation using transfected HEK293T cells. FEBS Lett 2019; 594:530-539. [PMID: 31557308 DOI: 10.1002/1873-3468.13622] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2019] [Revised: 09/10/2019] [Accepted: 09/21/2019] [Indexed: 11/09/2022]
Abstract
Elevated fatty acid (FA) levels contribute to severe metabolic diseases. Unbalanced oversupply of saturated FAs is particularly damaging, which renders stearoyl-CoA desaturase (SCD1) activity an important factor of resistance. A SCD1-related oxidoreductase protects cells against palmitate toxicity, so we aimed to test whether desaturase activity is limited by SCD1 itself or by the associated electron supply. Unsaturated/saturated FA ratio was markedly elevated by SCD1 overexpression while it remained unaffected by the overexpression of SCD1-related electron transfer proteins in HEK293T cells. Electron supply was not rate-limiting either in palmitate-treated cells or in cells with enhanced SCD1 expression. Our findings indicate the rate-limiting role of SCD1 itself, and that FA desaturation cannot be facilitated by reinforcing the electron supply of the enzyme.
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Affiliation(s)
- Veronika Zámbó
- Department of Medical Chemistry, Molecular Biology and Pathobiochemistry, Semmelweis University, Budapest, Hungary
| | - Laura Simon-Szabó
- Pathobiochemistry Research Group, Hungarian Academy of Sciences, Semmelweis University (MTA-SE), Budapest, Hungary
| | - Farkas Sarnyai
- Department of Medical Chemistry, Molecular Biology and Pathobiochemistry, Semmelweis University, Budapest, Hungary
| | | | - Zsófia Gór-Nagy
- Department of Inorganic and Analytical Chemistry, Budapest University of Technology and Economics, Hungary
| | - Anna Somogyi
- Department of Medical Chemistry, Molecular Biology and Pathobiochemistry, Semmelweis University, Budapest, Hungary
| | - Péter Szelényi
- Department of Medical Chemistry, Molecular Biology and Pathobiochemistry, Semmelweis University, Budapest, Hungary
| | - Éva Kereszturi
- Department of Medical Chemistry, Molecular Biology and Pathobiochemistry, Semmelweis University, Budapest, Hungary
| | - Blanka Tóth
- Department of Inorganic and Analytical Chemistry, Budapest University of Technology and Economics, Hungary
| | - Miklós Csala
- Department of Medical Chemistry, Molecular Biology and Pathobiochemistry, Semmelweis University, Budapest, Hungary
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60
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Ogino N, Miyagawa K, Kusanaga M, Hayashi T, Minami S, Oe S, Honma Y, Harada M. Involvement of sarco/endoplasmic reticulum calcium ATPase-mediated calcium flux in the protective effect of oleic acid against lipotoxicity in hepatocytes. Exp Cell Res 2019; 385:111651. [PMID: 31568762 DOI: 10.1016/j.yexcr.2019.111651] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2019] [Revised: 09/22/2019] [Accepted: 09/26/2019] [Indexed: 12/14/2022]
Abstract
Elevated free fatty acids, particularly saturated ones such as palmitic acid, may play an important role in the lipotoxic mechanism of nonalcoholic fatty liver disease (NAFLD). Saturated fatty acids induce autophagy dysfunction and endoplasmic reticulum (ER) stress leading to apoptosis in hepatocytes. However, unsaturated fatty acids, such as oleic acid, are nontoxic and can even prevent saturated fatty acid-induced toxicity in vitro. Although emerging evidence has suggested that ER calcium flux disruption in hepatocytes is involved in NAFLD pathogenesis, the roles of fatty acids in autophagy and ER calcium flux still remain unclear. We demonstrated that oleic acid ameliorated palmitic acid-induced autophagy arrest and ER stress in parallel with ER calcium depletion in hepatocytes. Moreover, we found that the effect of oleic acid against autophagy arrest was reversed by the pharmacological inhibition of sarcoplasmic reticulum Ca2+-ATPase (SERCA), which influxes calcium to ER. These data suggest that SERCA-mediated ER calcium flux is greatly involved in fatty acid-induced lipotoxicity in hepatocytes, and the prevention of ER calcium depletion may restore saturated fatty acid-induced autophagy arrest in hepatocytes.
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Affiliation(s)
- Noriyoshi Ogino
- Third Department of Internal Medicine, School of Medicine, University of Occupational and Environmental Health, Kitakyushu, Japan.
| | - Koichiro Miyagawa
- Third Department of Internal Medicine, School of Medicine, University of Occupational and Environmental Health, Kitakyushu, Japan
| | - Masashi Kusanaga
- Third Department of Internal Medicine, School of Medicine, University of Occupational and Environmental Health, Kitakyushu, Japan
| | - Tsuguru Hayashi
- Third Department of Internal Medicine, School of Medicine, University of Occupational and Environmental Health, Kitakyushu, Japan
| | - Sota Minami
- Third Department of Internal Medicine, School of Medicine, University of Occupational and Environmental Health, Kitakyushu, Japan
| | - Shinji Oe
- Third Department of Internal Medicine, School of Medicine, University of Occupational and Environmental Health, Kitakyushu, Japan
| | - Yuichi Honma
- Third Department of Internal Medicine, School of Medicine, University of Occupational and Environmental Health, Kitakyushu, Japan
| | - Masaru Harada
- Third Department of Internal Medicine, School of Medicine, University of Occupational and Environmental Health, Kitakyushu, Japan.
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61
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Ali ES, Rychkov GY, Barritt GJ. Deranged hepatocyte intracellular Ca 2+ homeostasis and the progression of non-alcoholic fatty liver disease to hepatocellular carcinoma. Cell Calcium 2019; 82:102057. [PMID: 31401389 DOI: 10.1016/j.ceca.2019.102057] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Revised: 06/29/2019] [Accepted: 07/01/2019] [Indexed: 12/12/2022]
Abstract
Hepatocellular carcinoma (HCC) is the second leading cause of cancer-related deaths in men, and the sixth in women. Non-alcoholic fatty liver disease (NAFLD) is now one of the major risk factors for HCC. NAFLD, which involves the accumulation of excess lipid in cytoplasmic lipid droplets in hepatocytes, can progress to non-alcoholic steatosis, fibrosis, and HCC. Changes in intracellular Ca2+ constitute important signaling pathways for the regulation of lipid and carbohydrate metabolism in normal hepatocytes. Recent studies of steatotic hepatocytes have identified lipid-induced changes in intracellular Ca2+, and have provided evidence that altered Ca2+ signaling exacerbates lipid accumulation and may promote HCC. The aims of this review are to summarise current knowledge of the lipid-induced changes in hepatocyte Ca2+ homeostasis, to comment on the mechanisms involved, and discuss the pathways leading from altered Ca2+ homeostasis to enhanced lipid accumulation and the potential promotion of HCC. In steatotic hepatocytes, lipid inhibits store-operated Ca2+ entry and SERCA2b, and activates Ca2+ efflux from the endoplasmic reticulum (ER) and its transfer to mitochondria. These changes are associated with changes in Ca2+ concentrations in the ER (decreased), cytoplasmic space (increased) and mitochondria (likely increased). They lead to: inhibition of lipolysis, lipid autophagy, lipid oxidation, and lipid secretion; activation of lipogenesis; increased lipid; ER stress, generation of reactive oxygen species (ROS), activation of Ca2+/calmodulin-dependent kinases and activation of transcription factor Nrf2. These all can potentially mediate the transition of NAFLD to HCC. It is concluded that lipid-induced changes in hepatocyte Ca2+ homeostasis are important in the initiation and progression of HCC. Further research is desirable to better understand the cause and effect relationships, the time courses and mechanisms involved, and the potential of Ca2+ transporters, channels, and binding proteins as targets for pharmacological intervention.
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Affiliation(s)
- Eunus S Ali
- Department of Medical Biochemistry, College of Medicine and Public Health, Flinders University, Adelaide, South Australia, 5001, Australia
| | - Grigori Y Rychkov
- School of Medicine, The University of Adelaide, and South Australian Health and Medical Research Institute, Adelaide, South Australia, 5005, Australia
| | - Greg J Barritt
- Department of Medical Biochemistry, College of Medicine and Public Health, Flinders University, Adelaide, South Australia, 5001, Australia.
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Lu YT, Xiao YF, Li YF, Li J, Nan FJ, Li JY. Sulfuretin protects hepatic cells through regulation of ROS levels and autophagic flux. Acta Pharmacol Sin 2019; 40:908-918. [PMID: 30560904 DOI: 10.1038/s41401-018-0193-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2018] [Accepted: 11/08/2018] [Indexed: 12/09/2022] Open
Abstract
Palmitate (PA) exposure induces stress conditions featuring ROS accumulation and upregulation of p62 expression, resulting in autophagic flux blockage and cell apoptosis. Sulfuretin (Sul) is a natural product isolated from Rhus verniciflua Stokes; the cytoprotective effect of Sul on human hepatic L02 cells and mouse primary hepatocytes under PA-induced stress conditions was investigated in this study. Sul induced mitophagy by activation of p-TBK1 and LC3 and produced a concomitant decline in p62 expression. Autophagosome formation and mitophagy were assessed by the sensitive dual fluorescence reporter mCherry-EGFP-LC3B, and mitochondrial fragmentation was analyzed using MitoTracker Deep Red FM. A preliminary structure-activity relationship (SAR) for Sul was also investigated, and the phenolic hydroxyl group was found to be pivotal for maintaining the cytoprotective bioactivity of Sul. Furthermore, experiments using flow cytometry and western blots revealed that Sul reversed the cytotoxic effect stimulated by the autophagy inhibitors 3-methyladenine (3-MA) and chloroquine (CQ), and its cytoprotective effect was almost eliminated when the autophagy-related 5 (Atg5) gene was knocked down. These studies suggest that, in addition to its antioxidative effects, Sul stimulates mitophagy and restores impaired autophagic flux, thus protecting hepatic cells from apoptosis, and that Sul has potential future medical applications for hepatoprotection.
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63
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Yang L, Wei J, Sheng F, Li P. Attenuation of Palmitic Acid-Induced Lipotoxicity by Chlorogenic Acid through Activation of SIRT1 in Hepatocytes. Mol Nutr Food Res 2019; 63:e1801432. [PMID: 31168914 DOI: 10.1002/mnfr.201801432] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2018] [Revised: 03/28/2019] [Indexed: 12/22/2022]
Abstract
SCOPE Saturated free fatty acids (FFAs) induce hepatocyte lipotoxicity, wherein oxidative stress-associated mitochondrial dysfunction is mechanistically involved. Chlorogenic acid (CGA), a potent antioxidant and anti-inflammatory compound, protects against high-fat-diet-induced oxidative stress and mitochondrial dysfunction in liver. This study investigates whether CGA protects against FFA-induced hepatocyte lipotoxicity via the regulation of mitochondrial fission/fusion and elucidates its underlying mechanisms. METHODS AND RESULTS AML12 cell, a non-transformed hepatocyte cell line, is treated with palmitate. Here, it is shown that CGA prevents palmitate-induced lipotoxicity by activation of SIRT1 regulated mitochondrial morphology. CGA treatment mitigates oxidative stress and mitochondrial dysfunction, as evidenced by a decrease in reactive oxygen species (ROS) production, and an increase in mitochondrial mass and mitochondrial membrane potential. CGA also significantly decreases Bax expression and thereby reduces mitochondria-mediated caspase-dependent apoptosis. Mechanistically, CGA attenuates ROS-induced mitochondrial fragmentation by inhibiting dynamin-related protein 1 (Drp1) and enhancing Mfn2 expression. In contrast, the inhibitory effects of CGA on the generation of mitochondrial ROS and Drp1 are blocked by siRNA knockdown of SIRT1. CONCLUSION Collectively, these findings show that supplementation with CGA protects hepatocytes from FFA-induced lipotoxicity through activation of SIRT1, which reverses the oxidative stress and dysfunction of mitochondrial biogenesis directly.
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Affiliation(s)
- Lele Yang
- State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macau, 999078, China
| | - Jinchao Wei
- State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macau, 999078, China
| | - Feiya Sheng
- State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macau, 999078, China
| | - Peng Li
- State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macau, 999078, China
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Abstract
Genomic instability is a common feature of tumours that has a wide range of disruptive effects on cellular homeostasis. In this review we briefly discuss how instability comes about, then focus on the impact of gain or loss of DNA (aneuploidy) on oxidative stress. We discuss several mechanisms that lead from aneuploidy to the production of reactive oxygen species, including the effects on protein complex stoichiometry, endoplasmic reticulum stress and metabolic disruption. Each of these are involved in positive feedback loops that amplify relatively minor genetic changes into major cellular disruption or cell death, depending on the capacity of the cell to induce antioxidants or processes such as mitophagy that can moderate the disruption. Finally we examine the direct effects of reactive oxygen species on mitosis and how oxidative stress can compromise centrosome number, cytoskeletal integrity and signalling processes that are vital for mitotic fidelity.
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Affiliation(s)
- David L Newman
- a Department of Molecular and Biomedical Science, University of Adelaide , Adelaide , Australia
| | - Lauren A Thurgood
- b Discipline of Molecular Medicine and Pathology and Flinders Centre for Innovation in Cancer, College of Medicine and Public Health, Flinders University , Adelaide , Australia
| | - Stephen L Gregory
- a Department of Molecular and Biomedical Science, University of Adelaide , Adelaide , Australia.,b Discipline of Molecular Medicine and Pathology and Flinders Centre for Innovation in Cancer, College of Medicine and Public Health, Flinders University , Adelaide , Australia
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65
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Mwangi SM, Li G, Ye L, Liu Y, Reichardt F, Yeligar SM, Hart CM, Czaja MJ, Srinivasan S. Glial Cell Line-Derived Neurotrophic Factor Enhances Autophagic Flux in Mouse and Rat Hepatocytes and Protects Against Palmitate Lipotoxicity. Hepatology 2019; 69:2455-2470. [PMID: 30715741 PMCID: PMC6541506 DOI: 10.1002/hep.30541] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/07/2018] [Accepted: 01/25/2019] [Indexed: 12/16/2022]
Abstract
Glial cell line-derived neurotrophic factor (GDNF) is a protein that is required for the development and survival of enteric, sympathetic, and catecholaminergic neurons. We previously reported that GDNF is protective against high fat diet (HFD)-induced hepatic steatosis in mice through suppression of hepatic expression of peroxisome proliferator activated receptor-γ and genes encoding enzymes involved in de novo lipogenesis. We also reported that transgenic overexpression of GDNF in mice prevented the HFD-induced liver accumulation of the autophagy cargo-associated protein p62/sequestosome 1 characteristic of impaired autophagy. Here we investigated the effects of GDNF on hepatic autophagy in response to increased fat load, and on hepatocyte mitochondrial fatty acid β-oxidation and cell survival. GDNF not only prevented the reductions in the liver levels of some key autophagy-related proteins, including Atg5, Atg7, Beclin-1 and LC3A/B-II, seen in HFD-fed control mice, but enhanced their levels after 12 weeks of HFD feeding. In vitro, GDNF accelerated autophagic cargo clearance in primary mouse hepatocytes and a rat hepatocyte cell line, and reduced the phosphorylation of the mechanistic target of rapamycin complex downstream-target p70S6 kinase similar to the autophagy activator rapamycin. GDNF also enhanced mitochondrial fatty acid β-oxidation in primary mouse and rat hepatocytes, and protected against palmitate-induced lipotoxicity. Conclusion: We demonstrate a role for GDNF in enhancing hepatic autophagy and in potentiating mitochondrial function and fatty acid oxidation. Our studies show that GDNF and its receptor agonists could be useful for enhancing hepatocyte survival and protecting against fatty acid-induced hepatic lipotoxicity.
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Affiliation(s)
- Simon Musyoka Mwangi
- Division of Digestive Diseases, Department of Medicine, Emory University School of Medicine, Atlanta, GA
- Research-Gastroenterology, Atlanta VA Health Care System, Decatur, GA, United States
| | - Ge Li
- Division of Digestive Diseases, Department of Medicine, Emory University School of Medicine, Atlanta, GA
- Research-Gastroenterology, Atlanta VA Health Care System, Decatur, GA, United States
| | - Lan Ye
- Division of Digestive Diseases, Department of Medicine, Emory University School of Medicine, Atlanta, GA
- Research-Gastroenterology, Atlanta VA Health Care System, Decatur, GA, United States
| | - Yunshan Liu
- Division of Digestive Diseases, Department of Medicine, Emory University School of Medicine, Atlanta, GA
| | - Francois Reichardt
- Division of Digestive Diseases, Department of Medicine, Emory University School of Medicine, Atlanta, GA
- Research-Gastroenterology, Atlanta VA Health Care System, Decatur, GA, United States
| | - Samantha M. Yeligar
- Division of Pulmonary, Allergy, Critical Care and Sleep Medicine, Department of Medicine, Emory University School of Medicine, Atlanta, GA
- Research-Pulmonary, Atlanta VA Health Care System, Decatur, GA
| | - C. Michael Hart
- Division of Pulmonary, Allergy, Critical Care and Sleep Medicine, Department of Medicine, Emory University School of Medicine, Atlanta, GA
- Research-Pulmonary, Atlanta VA Health Care System, Decatur, GA
| | - Mark J. Czaja
- Division of Digestive Diseases, Department of Medicine, Emory University School of Medicine, Atlanta, GA
| | - Shanthi Srinivasan
- Division of Digestive Diseases, Department of Medicine, Emory University School of Medicine, Atlanta, GA
- Research-Gastroenterology, Atlanta VA Health Care System, Decatur, GA, United States
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Guo Q, Hu H, Liu X, Yang D, Yin Y, Zhang B, He H, Oh Y, Wu Q, Liu C, Gu N. C/EBPβ mediates palmitate-induced musclin expression via the regulation of PERK/ATF4 pathways in myotubes. Am J Physiol Endocrinol Metab 2019; 316:E1081-E1092. [PMID: 30964708 DOI: 10.1152/ajpendo.00478.2018] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Musclin is a muscle-secreted cytokine that disrupts glucose uptake and glycogen synthesis in type 2 diabetes. The purpose of this study was to investigate the mechanisms responsible for the regulation of musclin gene expression in response to treatment with palmitate. RNA sequencing results showed that biological processes activated by palmitate are mainly enriched in endoplasmic reticulum (ER) stress. The protein kinase RNA-like ER kinase (PERK) signaling pathway is involved in the regulation of musclin expression induced by palmitate. Chromatin immunoprecipitation data showed that activating transcription factor 4 (ATF4)-downstream of PERK-bound to the promoter of the C/EBPβ gene. Notably, C/EBPβ also contains a binding site in the region -94~-52 of the musclin gene promoter. Knockdown or knockout of PERK and ATF4 using short hairpin RNA or CRISPR-Cas9 decreased the expression of C/EBPβ and musclin induced by palmitate. Furthermore, knockdown and knockout of C/EBPβ alleviated the high expression of musclin in response to treatment with palmitate. Moreover, CRISPR-Cas9 knockout of the region -94~-52 in which C/EBPβ binds to the promoter of musclin abrogated the induction of high musclin expression caused by palmitate. Collectively, these findings suggest that treatment with palmitate activates the PERK/ATF4 signaling pathway, which in turn increases the expression of C/EBPβ. C/EBPβ binds directly to the promoter of the musclin gene and upregulates its expression.
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Affiliation(s)
- Qian Guo
- School of Life Science and Technology, Harbin Institute of Technology , Harbin , China
| | - Hailong Hu
- School of Life Science and Technology, Harbin Institute of Technology , Harbin , China
| | - Xiaohuan Liu
- School of Life Science and Technology, Harbin Institute of Technology , Harbin , China
| | - DaQian Yang
- School of Life Science and Technology, Harbin Institute of Technology , Harbin , China
| | - Yao Yin
- School of Life Science and Technology, Harbin Institute of Technology , Harbin , China
| | - Boya Zhang
- School of Life Science and Technology, Harbin Institute of Technology , Harbin , China
| | - Hongjuan He
- School of Life Science and Technology, Harbin Institute of Technology , Harbin , China
| | - Yuri Oh
- Faculty of Education, Wakayama University , Wakayama , Japan
| | - Qiong Wu
- School of Life Science and Technology, Harbin Institute of Technology , Harbin , China
| | - Chuanpeng Liu
- School of Life Science and Technology, Harbin Institute of Technology , Harbin , China
| | - Ning Gu
- School of Life Science and Technology, Harbin Institute of Technology , Harbin , China
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67
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Ren X, Chen N, Chen Y, Liu W, Hu Y. TRB3 stimulates SIRT1 degradation and induces insulin resistance by lipotoxicity via COP1. Exp Cell Res 2019; 382:111428. [PMID: 31125554 DOI: 10.1016/j.yexcr.2019.05.009] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2019] [Revised: 04/05/2019] [Accepted: 05/08/2019] [Indexed: 11/26/2022]
Abstract
Fatty acid-induced lipotoxicity plays an important role in the pathogenesis of diabetes mellitus. Our previous studies have documented that lipotoxicity contributes to the onset and development of diabetes via insulin resistance and/or compromised function of the pancreatic β-cells. However, the underlying molecular mechanisms associating lipotoxicity with insulin resistance remain to be fully elucidated. In this study, we explored the role of TRB3-COP1-SIRT1 in lipotoxicity leading to insulin resistance in hepatocytes. High fat diet (HFD)-fed mice and hepG2 cells stimulated with palmitate were utilized as models of lipid metabolism disorders. We analyzed the interactions of SIRT1 and COP1 with each other and with TRB3 using co-immunoprecipitation, western blotting. SIRT1 ubiquitination was also explored. Animal and cell experiments showed that lipotoxicity induced SIRT1 down-regulation at the protein level without altering the mRNA level, whereas, lipotoxicity led to up-regulation of TRB3 and COP1 at both the gene and protein levels. Mechanistic analysis indicated that COP1 functioned as an E3 Ub-ligase of SIRT1, responsible for its proteasomal degradation under lipotoxic conditions. TRB3 recruited COP1 to SIRT1 to promote its ubiquitination. Our data indicated for the first time that TRB3-COP1-SIRT1 pathway played an important role in lipotoxicity leading to insulin resistance in hepatocytes, and suggested that COP1 could be a potential therapeutic choice for the treatment of diabetes mellitus, with lipotoxicity being the important pathomechanism.
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Affiliation(s)
- Xingxing Ren
- Department of Endocrinology, Renji Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, 200127, China
| | - Ningxin Chen
- Department of Endocrinology, Renji Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, 200127, China
| | - Yawen Chen
- Department of Endocrinology, Renji Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, 200127, China
| | - Wei Liu
- Department of Endocrinology, Renji Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, 200127, China.
| | - Yaomin Hu
- Department of Endocrinology, Renji Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, 200127, China.
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68
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Luangmonkong T, Suriguga S, Mutsaers HAM, Groothuis GMM, Olinga P, Boersema M. Targeting Oxidative Stress for the Treatment of Liver Fibrosis. Rev Physiol Biochem Pharmacol 2019; 175:71-102. [PMID: 29728869 DOI: 10.1007/112_2018_10] [Citation(s) in RCA: 152] [Impact Index Per Article: 30.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Oxidative stress is a reflection of the imbalance between the production of reactive oxygen species (ROS) and the scavenging capacity of the antioxidant system. Excessive ROS, generated from various endogenous oxidative biochemical enzymes, interferes with the normal function of liver-specific cells and presumably plays a role in the pathogenesis of liver fibrosis. Once exposed to harmful stimuli, Kupffer cells (KC) are the main effectors responsible for the generation of ROS, which consequently affect hepatic stellate cells (HSC) and hepatocytes. ROS-activated HSC undergo a phenotypic switch and deposit an excessive amount of extracellular matrix that alters the normal liver architecture and negatively affects liver function. Additionally, ROS stimulate necrosis and apoptosis of hepatocytes, which causes liver injury and leads to the progression of end-stage liver disease. In this review, we overview the role of ROS in liver fibrosis and discuss the promising therapeutic interventions related to oxidative stress. Most importantly, novel drugs that directly target the molecular pathways responsible for ROS generation, namely, mitochondrial dysfunction inhibitors, endoplasmic reticulum stress inhibitors, NADPH oxidase (NOX) inhibitors, and Toll-like receptor (TLR)-affecting agents, are reviewed in detail. In addition, challenges for targeting oxidative stress in the management of liver fibrosis are discussed.
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Affiliation(s)
- Theerut Luangmonkong
- Department of Pharmaceutical Technology and Biopharmacy, University of Groningen, Groningen, The Netherlands.,Department of Pharmacology, Faculty of Pharmacy, Mahidol University, Bangkok, Thailand
| | - Su Suriguga
- Department of Pharmaceutical Technology and Biopharmacy, University of Groningen, Groningen, The Netherlands
| | - Henricus A M Mutsaers
- Department of Pharmaceutical Technology and Biopharmacy, University of Groningen, Groningen, The Netherlands.,Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
| | - Geny M M Groothuis
- Department of Pharmacokinetics, Toxicology and Targeting, University of Groningen, Groningen, The Netherlands
| | - Peter Olinga
- Department of Pharmaceutical Technology and Biopharmacy, University of Groningen, Groningen, The Netherlands.
| | - Miriam Boersema
- Department of Pharmaceutical Technology and Biopharmacy, University of Groningen, Groningen, The Netherlands
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69
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Thoudam T, Ha CM, Leem J, Chanda D, Park JS, Kim HJ, Jeon JH, Choi YK, Liangpunsakul S, Huh YH, Kwon TH, Park KG, Harris RA, Park KS, Rhee HW, Lee IK. PDK4 Augments ER-Mitochondria Contact to Dampen Skeletal Muscle Insulin Signaling During Obesity. Diabetes 2019; 68:571-586. [PMID: 30523025 PMCID: PMC6385748 DOI: 10.2337/db18-0363] [Citation(s) in RCA: 106] [Impact Index Per Article: 21.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/29/2018] [Accepted: 11/20/2018] [Indexed: 12/17/2022]
Abstract
Mitochondria-associated endoplasmic reticulum membrane (MAM) is a structural link between mitochondria and endoplasmic reticulum (ER). MAM regulates Ca2+ transport from the ER to mitochondria via an IP3R1-GRP75-VDAC1 complex-dependent mechanism. Excessive MAM formation may cause mitochondrial Ca2+ overload and mitochondrial dysfunction. However, the exact implication of MAM formation in metabolic syndromes remains debatable. Here, we demonstrate that PDK4 interacts with and stabilizes the IP3R1-GRP75-VDAC1 complex at the MAM interface. Obesity-induced increase in PDK4 activity augments MAM formation and suppresses insulin signaling. Conversely, PDK4 inhibition dampens MAM formation and improves insulin signaling by preventing MAM-induced mitochondrial Ca2+ accumulation, mitochondrial dysfunction, and ER stress. Furthermore, Pdk4-/- mice exhibit reduced MAM formation and are protected against diet-induced skeletal muscle insulin resistance. Finally, forced formation and stabilization of MAMs with synthetic ER-mitochondria linker prevented the beneficial effects of PDK4 deficiency on insulin signaling. Overall, our findings demonstrate a critical mediatory role of PDK4 in the development of skeletal muscle insulin resistance via enhancement of MAM formation.
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Affiliation(s)
- Themis Thoudam
- Department of Biomedical Science, The Graduate School, Kyungpook National University, Daegu, Republic of Korea
- BK21 Plus KNU Biomedical Convergence Program, Department of Biomedical Science, Kyungpook National University, Daegu, Republic of Korea
| | - Chae-Myeong Ha
- Department of Biomedical Science, The Graduate School, Kyungpook National University, Daegu, Republic of Korea
- BK21 Plus KNU Biomedical Convergence Program, Department of Biomedical Science, Kyungpook National University, Daegu, Republic of Korea
| | - Jaechan Leem
- Department of Immunology, School of Medicine, Catholic University of Daegu, Daegu, Republic of Korea
| | - Dipanjan Chanda
- Leading-Edge Research Center for Drug Discovery and Development for Diabetes and Metabolic Disease, Kyungpook National University Hospital, Daegu, Republic of Korea
| | - Jong-Seok Park
- Department of Chemistry, Ulsan National Institute of Science and Technology, Ulsan, Republic of Korea
| | - Hyo-Jeong Kim
- Electron Microscopy Research Center, Korea Basic Science Institute, Ochang, Chungbuk, Republic of Korea
| | - Jae-Han Jeon
- Leading-Edge Research Center for Drug Discovery and Development for Diabetes and Metabolic Disease, Kyungpook National University Hospital, Daegu, Republic of Korea
- Department of Internal Medicine, School of Medicine, Kyungpook National University, Kyungpook National University Hospital, Daegu, Republic of Korea
| | - Yeon-Kyung Choi
- Leading-Edge Research Center for Drug Discovery and Development for Diabetes and Metabolic Disease, Kyungpook National University Hospital, Daegu, Republic of Korea
- Department of Internal Medicine, School of Medicine, Kyungpook National University, Kyungpook National University Hospital, Daegu, Republic of Korea
| | - Suthat Liangpunsakul
- Division of Gastroenterology and Hepatology, Department of Medicine, Indiana University School of Medicine, Indianapolis, IN
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, IN
- Richard L. Roudebush VA Medical Center, Indianapolis, IN
| | - Yang Hoon Huh
- Electron Microscopy Research Center, Korea Basic Science Institute, Ochang, Chungbuk, Republic of Korea
| | - Tae-Hwan Kwon
- Department of Biomedical Science, The Graduate School, Kyungpook National University, Daegu, Republic of Korea
- BK21 Plus KNU Biomedical Convergence Program, Department of Biomedical Science, Kyungpook National University, Daegu, Republic of Korea
| | - Keun-Gyu Park
- Leading-Edge Research Center for Drug Discovery and Development for Diabetes and Metabolic Disease, Kyungpook National University Hospital, Daegu, Republic of Korea
- Department of Internal Medicine, School of Medicine, Kyungpook National University, Kyungpook National University Hospital, Daegu, Republic of Korea
| | - Robert A Harris
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, IN
| | - Kyu-Sang Park
- Department of Physiology, Institute of Lifestyle Medicine, Yonsei University Wonju College of Medicine, Gangwon-Do, Republic of Korea
| | - Hyun-Woo Rhee
- Department of Chemistry, Seoul National University, Seoul, Republic of Korea
| | - In-Kyu Lee
- Leading-Edge Research Center for Drug Discovery and Development for Diabetes and Metabolic Disease, Kyungpook National University Hospital, Daegu, Republic of Korea
- Department of Internal Medicine, School of Medicine, Kyungpook National University, Kyungpook National University Hospital, Daegu, Republic of Korea
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Bessone F, Razori MV, Roma MG. Molecular pathways of nonalcoholic fatty liver disease development and progression. Cell Mol Life Sci 2019; 76:99-128. [PMID: 30343320 PMCID: PMC11105781 DOI: 10.1007/s00018-018-2947-0] [Citation(s) in RCA: 325] [Impact Index Per Article: 65.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2018] [Revised: 10/10/2018] [Accepted: 10/15/2018] [Indexed: 02/06/2023]
Abstract
Nonalcoholic fatty liver disease (NAFLD) is a main hepatic manifestation of metabolic syndrome. It represents a wide spectrum of histopathological abnormalities ranging from simple steatosis to nonalcoholic steatohepatitis (NASH) with or without fibrosis and, eventually, cirrhosis and hepatocellular carcinoma. While hepatic simple steatosis seems to be a rather benign manifestation of hepatic triglyceride accumulation, the buildup of highly toxic free fatty acids associated with insulin resistance-induced massive free fatty acid mobilization from adipose tissue and the increased de novo hepatic fatty acid synthesis from glucose acts as the "first hit" for NAFLD development. NAFLD progression seems to involve the occurrence of "parallel, multiple-hit" injuries, such as oxidative stress-induced mitochondrial dysfunction, endoplasmic reticulum stress, endotoxin-induced, TLR4-dependent release of inflammatory cytokines, and iron overload, among many others. These deleterious factors are responsible for the triggering of a number of signaling cascades leading to inflammation, cell death, and fibrosis, the hallmarks of NASH. This review is aimed at integrating the overwhelming progress made in the characterization of the physiopathological mechanisms of NAFLD at a molecular level, to better understand the factor influencing the initiation and progression of the disease.
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Affiliation(s)
- Fernando Bessone
- Hospital Provincial del Centenario, Facultad de Ciencias Médicas, Servicio de Gastroenterología y Hepatología, Universidad Nacional de Rosario, Rosario, Argentina
| | - María Valeria Razori
- Instituto de Fisiología Experimental (IFISE-CONICET), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 570, 2000, Rosario, Argentina
| | - Marcelo G Roma
- Instituto de Fisiología Experimental (IFISE-CONICET), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 570, 2000, Rosario, Argentina.
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71
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Singh A, Zhi L, Zhang H. LRRK2 and mitochondria: Recent advances and current views. Brain Res 2019; 1702:96-104. [PMID: 29894679 PMCID: PMC6281802 DOI: 10.1016/j.brainres.2018.06.010] [Citation(s) in RCA: 79] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2018] [Revised: 05/17/2018] [Accepted: 06/07/2018] [Indexed: 12/21/2022]
Abstract
Mutations in the leucine-rich repeat kinase 2 (LRRK2) gene account for most common causes of familial and sporadic Parkinson's disease (PD) and are one of the strongest genetic risk factors in sporadic PD. Pathways implicated in LRRK2-dependent neurodegeneration include cytoskeletal dynamics, vesicular trafficking, autophagy, mitochondria, and calcium homeostasis. However, the exact molecular mechanisms still need to be elucidated. Both genetic and environmental causes of PD have highlighted the importance of mitochondrial dysfunction in the pathogenesis of PD. Mitochondrial impairment has been observed in fibroblasts and iPSC-derived neural cells from PD patients with LRRK2 mutations, and LRRK2 has been shown to localize to mitochondria and to regulate its function. In this review we discuss recent discoveries relating to LRRK2 mutations and mitochondrial dysfunction.
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Affiliation(s)
- Alpana Singh
- Department of Neuroscience, Thomas Jefferson University, Philadelphia, United States
| | - Lianteng Zhi
- Department of Neuroscience, Thomas Jefferson University, Philadelphia, United States
| | - Hui Zhang
- Department of Neuroscience, Thomas Jefferson University, Philadelphia, United States.
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72
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Nonalcoholic Fatty Liver Disease: Basic Pathogenetic Mechanisms in the Progression From NAFLD to NASH. Transplantation 2019; 103:e1-e13. [DOI: 10.1097/tp.0000000000002480] [Citation(s) in RCA: 153] [Impact Index Per Article: 30.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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73
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Pinto BAS, França LM, Laurindo FRM, Paes AMDA. Unfolded Protein Response: Cause or Consequence of Lipid and Lipoprotein Metabolism Disturbances? ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1127:67-82. [DOI: 10.1007/978-3-030-11488-6_5] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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74
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Egnatchik RA, Leamy AK, Sacco SA, Cheah YE, Shiota M, Young JD. Glutamate-oxaloacetate transaminase activity promotes palmitate lipotoxicity in rat hepatocytes by enhancing anaplerosis and citric acid cycle flux. J Biol Chem 2018; 294:3081-3090. [PMID: 30563841 DOI: 10.1074/jbc.ra118.004869] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2018] [Revised: 12/04/2018] [Indexed: 12/17/2022] Open
Abstract
Hepatocyte lipotoxicity is characterized by aberrant mitochondrial metabolism, which predisposes cells to oxidative stress and apoptosis. Previously, we reported that translocation of calcium from the endoplasmic reticulum to mitochondria of palmitate-treated hepatocytes activates anaplerotic flux from glutamine to α-ketoglutarate (αKG), which subsequently enters the citric acid cycle (CAC) for oxidation. We hypothesized that increased glutamine anaplerosis fuels elevations in CAC flux and oxidative stress following palmitate treatment. To test this hypothesis, primary rat hepatocytes or immortalized H4IIEC3 rat hepatoma cells were treated with lipotoxic levels of palmitate while modulating anaplerotic pathways leading to αKG. We found that culture media supplemented with glutamine, glutamate, or dimethyl-αKG increased palmitate lipotoxicity compared with media that lacked these anaplerotic substrates. Knockdown of glutamate-oxaloacetate transaminase activity significantly reduced the lipotoxic effects of palmitate, whereas knockdown of glutamate dehydrogenase (Glud1) had no effect on palmitate lipotoxicity. 13C flux analysis of H4IIEC3 cells co-treated with palmitate and the pan-transaminase inhibitor aminooxyacetic acid confirmed that reductions in lipotoxic markers were associated with decreases in anaplerosis, CAC flux, and oxygen consumption. Taken together, these results demonstrate that lipotoxic palmitate treatments enhance anaplerosis in cultured rat hepatocytes, causing a shift to aberrant transaminase metabolism that fuels CAC dysregulation and oxidative stress.
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Affiliation(s)
| | | | | | | | - Masakazu Shiota
- Molecular Physiology and Biophysics, Vanderbilt University, Nashville, Tennessee 37235
| | - Jamey D Young
- From Chemical and Biomolecular Engineering and .,Molecular Physiology and Biophysics, Vanderbilt University, Nashville, Tennessee 37235
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75
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Matrine attenuates endoplasmic reticulum stress and mitochondrion dysfunction in nonalcoholic fatty liver disease by regulating SERCA pathway. J Transl Med 2018; 16:319. [PMID: 30458883 PMCID: PMC6245862 DOI: 10.1186/s12967-018-1685-2] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2018] [Accepted: 11/09/2018] [Indexed: 01/07/2023] Open
Abstract
Background Endoplasmic reticulum (ER) stress, which can promote lipid metabolism disorders and steatohepatitis, contributes significantly to the pathogenesis of nonalcoholic fatty liver disease (NAFLD). Calcium (Ca2+) homeostasis is considered to play a key role in ER stress. Matrine (Mat) has been applied for the treatment of hepatitis B, but its effect on NAFLD is still unknown, and there is no unified view of Mat on the regulation of ER stress in the previous literature. Methods The pharmacological effects were studied in high-fat-diet or methionine–choline-deficient diet induced C57BL/6J mice models and in palmitic acid (PA) induced L02 human liver cell model. Calcium fluorescence experiments, computational virtual docking analysis and biochemical assays were used in identifying the locus of Mat. Results The results showed that Mat-treated mice were more resistant to steatosis in the liver than vehicle-treated mice and that Mat significantly reduced hepatic inflammation, lipid peroxides. The beneficial effect of Mat was associated with suppressing ER stress and restoring mitochondrial dysfunction. Additionally, Mat decreased the PA-induced lipid accumulation, ER stress and cytosolic calcium level ([Ca2+]c) in hepatocyte cell lines in low and middle dose. However, the high dose Mat did not show satisfactory results in cell model. Calcium fluorescence experiments showed that Mat was able to regulate [Ca2+]c. By computational virtual docking analysis and biochemical assays, Mat was shown to influence [Ca2+]c via direct inhibition of SERCA. Conclusions The results showed that the bi-directional regulation of Mat to endoplasmic reticulum at different doses was based on the inhibition of SERCA. In addition, the results also provide a theoretical basis for Mat as a potential therapeutic strategy in NAFLD/NASH. Electronic supplementary material The online version of this article (10.1186/s12967-018-1685-2) contains supplementary material, which is available to authorized users.
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76
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Wang T, Yao W, Li J, He Q, Shao Y, Huang F. Acetyl-CoA from inflammation-induced fatty acids oxidation promotes hepatic malate-aspartate shuttle activity and glycolysis. Am J Physiol Endocrinol Metab 2018; 315:E496-E510. [PMID: 29763372 DOI: 10.1152/ajpendo.00061.2018] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Hepatic metabolic syndrome is associated with inflammation, as inflammation stimulates the reprogramming of nutrient metabolism and hepatic mitochondria-generated acetyl-CoA, but how acetyl-CoA affects the reprogramming of nutrient metabolism, especially glucose and fatty acids, in the condition of inflammation is still unclear. Here, we used an acute inflammation model in which pigs were injected with lipopolysaccharide (LPS) and found that hepatic glycolysis and fatty acid oxidation are both promoted. Acetyl-proteome profiling of LPS-infected pigs liver showed that inflammatory stress exacerbates the acetylation of mitochondrial proteins. Both mitochondrial glutamate oxaloacetate transaminase 2 (GOT2) and malate dehydrogenase 2 (MDH2) were acetylated, and the malate-aspartate shuttle (MAS) activity was stimulated to maintain glycolysis. With the use of 13C-carbon tracing in vitro, acetyl-CoA was found to be mainly supplied by lipid-derived fatty acid oxidation rather than glucose-derived pyruvate oxidative decarboxylation, while glucose was mainly used for lactate production in response to inflammatory stress. The results of the mitochondrial experiment showed that acetyl-CoA directly increases MDH2 and, in turn, the GOT2 acetylation level affects MAS activity. Treatment with palmitate in primary hepatocytes from LPS-injected pigs increased the hepatic production of acetyl-CoA, pyruvate, and lactate; MAS activity; and hepatic MDH2 and GOT2 hyperacetylation, while the deficiency of long-chain acetyl-CoA dehydrogenase resulted in the stabilization of these parameters. These observations suggest that acetyl-CoA produced by fatty acid oxidation promotes MAS activity and glycolysis via nonenzymatic acetylation during the inflammatory stress response.
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Affiliation(s)
- Tongxin Wang
- Department of Animal Nutrition and Feed Science, College of Animal Science and Technology, Huazhong Agricultural University , Wuhan , China
| | - Weilei Yao
- Department of Animal Nutrition and Feed Science, College of Animal Science and Technology, Huazhong Agricultural University , Wuhan , China
| | - Ji Li
- Department of Animal Nutrition and Feed Science, College of Animal Science and Technology, Huazhong Agricultural University , Wuhan , China
| | - Qiongyu He
- Department of Animal Nutrition and Feed Science, College of Animal Science and Technology, Huazhong Agricultural University , Wuhan , China
| | - Yafei Shao
- Department of Animal Nutrition and Feed Science, College of Animal Science and Technology, Huazhong Agricultural University , Wuhan , China
| | - Feiruo Huang
- Department of Animal Nutrition and Feed Science, College of Animal Science and Technology, Huazhong Agricultural University , Wuhan , China
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77
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Kanda T, Matsuoka S, Yamazaki M, Shibata T, Nirei K, Takahashi H, Kaneko T, Fujisawa M, Higuchi T, Nakamura H, Matsumoto N, Yamagami H, Ogawa M, Imazu H, Kuroda K, Moriyama M. Apoptosis and non-alcoholic fatty liver diseases. World J Gastroenterol 2018; 24:2661-2672. [PMID: 29991872 PMCID: PMC6034146 DOI: 10.3748/wjg.v24.i25.2661] [Citation(s) in RCA: 179] [Impact Index Per Article: 29.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/02/2018] [Revised: 06/04/2018] [Accepted: 06/21/2018] [Indexed: 02/06/2023] Open
Abstract
The number of patients with nonalcoholic fatty liver diseases (NAFLD) including nonalcoholic steatohepatitis (NASH), has been increasing. NASH causes cirrhosis and hepatocellular carcinoma (HCC) and is one of the most serious health problems in the world. The mechanism through which NASH progresses is still largely unknown. Activation of caspases, Bcl-2 family proteins, and c-Jun N-terminal kinase-induced hepatocyte apoptosis plays a role in the activation of NAFLD/NASH. Apoptotic hepatocytes stimulate immune cells and hepatic stellate cells toward the progression of fibrosis in the liver through the production of inflammasomes and cytokines. Abnormalities in glucose and lipid metabolism as well as microbiota accelerate these processes. The production of reactive oxygen species, oxidative stress, and endoplasmic reticulum stress is also involved. Cell death, including apoptosis, seems very important in the progression of NAFLD and NASH. Recently, inhibitors of apoptosis have been developed as drugs for the treatment of NASH and may prevent cirrhosis and HCC. Increased hepatocyte apoptosis may distinguish NASH from NAFLD, and the improvement of apoptosis could play a role in controlling the development of NASH. In this review, the association between apoptosis and NAFLD/NASH are discussed. This review could provide their knowledge, which plays a role in seeing the patients with NAFLD/NASH in daily clinical practice.
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Affiliation(s)
- Tatsuo Kanda
- Division of Gastroenterology and Hepatology, Department of Medicine, Nihon University School of Medicine, Itabashi-ku, Tokyo 173-8610, Japan
| | - Shunichi Matsuoka
- Division of Gastroenterology and Hepatology, Department of Medicine, Nihon University School of Medicine, Itabashi-ku, Tokyo 173-8610, Japan
| | - Motomi Yamazaki
- Division of Gastroenterology and Hepatology, Department of Medicine, Nihon University School of Medicine, Itabashi-ku, Tokyo 173-8610, Japan
| | - Toshikatsu Shibata
- Division of Gastroenterology and Hepatology, Department of Medicine, Nihon University School of Medicine, Itabashi-ku, Tokyo 173-8610, Japan
| | - Kazushige Nirei
- Division of Gastroenterology and Hepatology, Department of Medicine, Nihon University School of Medicine, Itabashi-ku, Tokyo 173-8610, Japan
| | - Hiroshi Takahashi
- Division of Gastroenterology and Hepatology, Department of Medicine, Nihon University School of Medicine, Itabashi-ku, Tokyo 173-8610, Japan
| | - Tomohiro Kaneko
- Division of Gastroenterology and Hepatology, Department of Medicine, Nihon University School of Medicine, Itabashi-ku, Tokyo 173-8610, Japan
| | - Mariko Fujisawa
- Division of Gastroenterology and Hepatology, Department of Medicine, Nihon University School of Medicine, Itabashi-ku, Tokyo 173-8610, Japan
| | - Teruhisa Higuchi
- Division of Gastroenterology and Hepatology, Department of Medicine, Nihon University School of Medicine, Itabashi-ku, Tokyo 173-8610, Japan
| | - Hitomi Nakamura
- Division of Gastroenterology and Hepatology, Department of Medicine, Nihon University School of Medicine, Itabashi-ku, Tokyo 173-8610, Japan
| | - Naoki Matsumoto
- Division of Gastroenterology and Hepatology, Department of Medicine, Nihon University School of Medicine, Itabashi-ku, Tokyo 173-8610, Japan
| | - Hiroaki Yamagami
- Division of Gastroenterology and Hepatology, Department of Medicine, Nihon University School of Medicine, Itabashi-ku, Tokyo 173-8610, Japan
| | - Masahiro Ogawa
- Division of Gastroenterology and Hepatology, Department of Medicine, Nihon University School of Medicine, Itabashi-ku, Tokyo 173-8610, Japan
| | - Hiroo Imazu
- Division of Gastroenterology and Hepatology, Department of Medicine, Nihon University School of Medicine, Itabashi-ku, Tokyo 173-8610, Japan
| | - Kazumichi Kuroda
- Division of Gastroenterology and Hepatology, Department of Medicine, Nihon University School of Medicine, Itabashi-ku, Tokyo 173-8610, Japan
| | - Mitsuhiko Moriyama
- Division of Gastroenterology and Hepatology, Department of Medicine, Nihon University School of Medicine, Itabashi-ku, Tokyo 173-8610, Japan
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78
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Oliva-Vilarnau N, Hankeova S, Vorrink SU, Mkrtchian S, Andersson ER, Lauschke VM. Calcium Signaling in Liver Injury and Regeneration. Front Med (Lausanne) 2018; 5:192. [PMID: 30023358 PMCID: PMC6039545 DOI: 10.3389/fmed.2018.00192] [Citation(s) in RCA: 52] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Accepted: 06/11/2018] [Indexed: 12/12/2022] Open
Abstract
The liver fulfills central roles in metabolic control and detoxification and, as such, is continuously exposed to a plethora of insults. Importantly, the liver has a unique ability to regenerate and can completely recoup from most acute, non-iterative insults. However, multiple conditions, including viral hepatitis, non-alcoholic fatty liver disease (NAFLD), long-term alcohol abuse and chronic use of certain medications, can cause persistent injury in which the regenerative capacity eventually becomes dysfunctional, resulting in hepatic scaring and cirrhosis. Calcium is a versatile secondary messenger that regulates multiple hepatic functions, including lipid and carbohydrate metabolism, as well as bile secretion and choleresis. Accordingly, dysregulation of calcium signaling is a hallmark of both acute and chronic liver diseases. In addition, recent research implicates calcium transients as essential components of liver regeneration. In this review, we provide a comprehensive overview of the role of calcium signaling in liver health and disease and discuss the importance of calcium in the orchestration of the ensuing regenerative response. Furthermore, we highlight similarities and differences in spatiotemporal calcium regulation between liver insults of different etiologies. Finally, we discuss intracellular calcium control as an emerging therapeutic target for liver injury and summarize recent clinical findings of calcium modulation for the treatment of ischemic-reperfusion injury, cholestasis and NAFLD.
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Affiliation(s)
- Nuria Oliva-Vilarnau
- Section of Pharmacogenetics, Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - Simona Hankeova
- Department of Biosciences and Nutrition, Karolinska Institutet, Huddinge, Sweden.,Faculty of Science, Institute of Experimental Biology, Masaryk University, Brno, Czechia
| | - Sabine U Vorrink
- Section of Pharmacogenetics, Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - Souren Mkrtchian
- Section of Pharmacogenetics, Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - Emma R Andersson
- Department of Biosciences and Nutrition, Karolinska Institutet, Huddinge, Sweden.,Department of Cell and Molecular Biology, Karolinska Institutet, Stockholm, Sweden
| | - Volker M Lauschke
- Section of Pharmacogenetics, Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
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79
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Anusornvongchai T, Nangaku M, Jao TM, Wu CH, Ishimoto Y, Maekawa H, Tanaka T, Shimizu A, Yamamoto M, Suzuki N, Sassa R, Inagi R. Palmitate deranges erythropoietin production via transcription factor ATF4 activation of unfolded protein response. Kidney Int 2018; 94:536-550. [PMID: 29887316 DOI: 10.1016/j.kint.2018.03.011] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2017] [Revised: 02/02/2018] [Accepted: 03/02/2018] [Indexed: 01/22/2023]
Abstract
Lipotoxicity plays an important role in the progression of chronic kidney damage via various mechanisms, such as endoplasmic reticulum stress. Several studies proposed renal lipotoxicity in glomerular and tubular cells but the effect of lipid on renal erythropoietin (EPO)-producing (REP) cells in the interstitium has not been elucidated. Since renal anemia is caused by derangement of EPO production in REP cells, we evaluated the effect of palmitate, a representative long-chain saturated fatty acid, on EPO production and the endoplasmic reticulum stress pathway. EPO production was suppressed by palmitate (palmitate-conjugated bovine serum albumin [BSA]) or a high palmitate diet, but not oleic acid-conjugated BSA or a high oleic acid diet, especially under cobalt-induced pseudo-hypoxia both in vitro and in vivo. Importantly, suppression of EPO production was not induced by a decrease in transcription factor HIF activity, while it was significantly associated with endoplasmic reticulum stress, particularly transcription factor ATF4 activation, which suppresses 3'-enhancer activity of the EPO gene. ATF4 knockdown by siRNA significantly attenuated the suppressive effect of palmitate on EPO production. Studies utilizing inherited super-anemic mice (ISAM) mated with EPO-Cre mice (ISAM-REC mice) for lineage-labeling of REP cells showed that ATF4 activation by palmitate suppressed EPO production in REP cells. Laser capture microdissection confirmed ATF4 activation in the interstitial area of ISAM-REC mice treated with palmitate-conjugated BSA. Thus, endoplasmic reticulum stress induced by palmitate suppressed EPO expression by REP cells in a manner independent of HIF activation. The link between endoplasmic reticulum stress, dyslipidemia, and hypoxia may contribute to development and progression of anemia in CKD.
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Affiliation(s)
- Thitinun Anusornvongchai
- Division of CKD Pathophysiology, The University of Tokyo Graduate School of Medicine, Tokyo, Japan; Department of Internal Medicine, Lerdsin General Hospital, Department of Medical Services, Bangkok, Thailand
| | - Masaomi Nangaku
- Division of Nephrology and Endocrinology, The University of Tokyo Graduate School of Medicine, Tokyo, Japan
| | - Tzu-Ming Jao
- Division of CKD Pathophysiology, The University of Tokyo Graduate School of Medicine, Tokyo, Japan
| | - Chia-Hsien Wu
- Division of Nephrology and Endocrinology, The University of Tokyo Graduate School of Medicine, Tokyo, Japan
| | - Yu Ishimoto
- Division of Nephrology and Endocrinology, The University of Tokyo Graduate School of Medicine, Tokyo, Japan
| | - Hiroshi Maekawa
- Division of Nephrology and Endocrinology, The University of Tokyo Graduate School of Medicine, Tokyo, Japan
| | - Tetsuhiro Tanaka
- Division of Nephrology and Endocrinology, The University of Tokyo Graduate School of Medicine, Tokyo, Japan
| | - Akira Shimizu
- Department of Analytic Human Pathology, Graduate School of Medicine, Nippon Medical School, Tokyo, Japan
| | - Masayuki Yamamoto
- Division of Interdisciplinary Medical Science, United Centers for Advanced Research and Translational Medicine, Tohoku University Graduate School of Medicine, Miyagi, Japan
| | - Norio Suzuki
- Division of Oxygen Biology, United Centers for Advanced Research and Translational Medicine, Tohoku University Graduate School of Medicine, Miyagi, Japan
| | | | - Reiko Inagi
- Division of CKD Pathophysiology, The University of Tokyo Graduate School of Medicine, Tokyo, Japan.
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80
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Honrath B, Krabbendam IE, IJsebaart C, Pegoretti V, Bendridi N, Rieusset J, Schmidt M, Culmsee C, Dolga AM. SK channel activation is neuroprotective in conditions of enhanced ER-mitochondrial coupling. Cell Death Dis 2018; 9:593. [PMID: 29789578 PMCID: PMC5964177 DOI: 10.1038/s41419-018-0590-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2017] [Revised: 04/08/2018] [Accepted: 04/12/2018] [Indexed: 12/26/2022]
Abstract
Alterations in the strength and interface area of contact sites between the endoplasmic reticulum (ER) and mitochondria contribute to calcium (Ca2+) dysregulation and neuronal cell death, and have been implicated in the pathology of several neurodegenerative diseases. Weakening this physical linkage may reduce Ca2+ uptake into mitochondria, while fortifying these organelle contact sites may promote mitochondrial Ca2+ overload and cell death. Small conductance Ca2+-activated K+ (SK) channels regulate mitochondrial respiration, and their activation attenuates mitochondrial damage in paradigms of oxidative stress. In the present study, we enhanced ER–mitochondrial coupling and investigated the impact of SK channels on survival of neuronal HT22 cells in conditions of oxidative stress. Using genetically encoded linkers, we show that mitochondrial respiration and the vulnerability of neuronal cells to oxidative stress was inversely linked to the strength of ER–mitochondrial contact points and the increase in mitochondrial Ca2+ uptake. Pharmacological activation of SK channels provided protection against glutamate-induced cell death and also in conditions of increased ER–mitochondrial coupling. Together, this study revealed that SK channel activation provided persistent neuroprotection in the paradigm of glutamate-induced oxytosis even in conditions where an increase in ER–mitochondrial coupling potentiated mitochondrial Ca2+ influx and impaired mitochondrial bioenergetics.
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Affiliation(s)
- Birgit Honrath
- Institute of Pharmacology and Clinical Pharmacy, University of Marburg, 35043, Marburg, Germany. .,Faculty of Science and Engineering, Groningen Research Institute of Pharmacy (GRIP), Research School of Behavioural and Cognitive Neurosciences (BCN), Department of Molecular Pharmacology, University of Groningen, 9713 AV, Groningen, The Netherlands.
| | - Inge E Krabbendam
- Faculty of Science and Engineering, Groningen Research Institute of Pharmacy (GRIP), Research School of Behavioural and Cognitive Neurosciences (BCN), Department of Molecular Pharmacology, University of Groningen, 9713 AV, Groningen, The Netherlands
| | - Carmen IJsebaart
- Faculty of Science and Engineering, Groningen Research Institute of Pharmacy (GRIP), Research School of Behavioural and Cognitive Neurosciences (BCN), Department of Molecular Pharmacology, University of Groningen, 9713 AV, Groningen, The Netherlands
| | - Valentina Pegoretti
- Faculty of Science and Engineering, Groningen Research Institute of Pharmacy (GRIP), Research School of Behavioural and Cognitive Neurosciences (BCN), Department of Molecular Pharmacology, University of Groningen, 9713 AV, Groningen, The Netherlands
| | - Nadia Bendridi
- INSERM U1060, INRA U1235, Laboratoire CarMeN, Lyon University, Université Claude Bernard Lyon1, INSA-Lyon, F-69921, Oullins, France
| | - Jennifer Rieusset
- INSERM U1060, INRA U1235, Laboratoire CarMeN, Lyon University, Université Claude Bernard Lyon1, INSA-Lyon, F-69921, Oullins, France
| | - Martina Schmidt
- Faculty of Science and Engineering, Groningen Research Institute of Pharmacy (GRIP), Research School of Behavioural and Cognitive Neurosciences (BCN), Department of Molecular Pharmacology, University of Groningen, 9713 AV, Groningen, The Netherlands
| | - Carsten Culmsee
- Institute of Pharmacology and Clinical Pharmacy, University of Marburg, 35043, Marburg, Germany
| | - Amalia M Dolga
- Institute of Pharmacology and Clinical Pharmacy, University of Marburg, 35043, Marburg, Germany. .,Faculty of Science and Engineering, Groningen Research Institute of Pharmacy (GRIP), Research School of Behavioural and Cognitive Neurosciences (BCN), Department of Molecular Pharmacology, University of Groningen, 9713 AV, Groningen, The Netherlands.
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81
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Xiao W, Zhang J, Chen S, Shi Y, Xiao F, An W. Alleviation of palmitic acid‐induced endoplasmic reticulum stress by augmenter of liver regeneration through IP3R‐controlled Ca
2+
release. J Cell Physiol 2018; 233:6148-6157. [DOI: 10.1002/jcp.26463] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2017] [Accepted: 01/05/2018] [Indexed: 01/12/2023]
Affiliation(s)
- Wei‐chun Xiao
- Department of Cell Biology and Municipal Laboratory for Liver Protection and Regulation of RegenerationCapital Medical UniversityBeijingChina
| | - Jing Zhang
- Department of Cell Biology and Municipal Laboratory for Liver Protection and Regulation of RegenerationCapital Medical UniversityBeijingChina
| | - Si‐li Chen
- Department of Cell Biology and Municipal Laboratory for Liver Protection and Regulation of RegenerationCapital Medical UniversityBeijingChina
| | - Yi‐jun Shi
- Department of Cell Biology and Municipal Laboratory for Liver Protection and Regulation of RegenerationCapital Medical UniversityBeijingChina
| | - Fan Xiao
- Department of Cell Biology and Municipal Laboratory for Liver Protection and Regulation of RegenerationCapital Medical UniversityBeijingChina
| | - Wei An
- Department of Cell Biology and Municipal Laboratory for Liver Protection and Regulation of RegenerationCapital Medical UniversityBeijingChina
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82
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Lang AL, Chen L, Poff GD, Ding WX, Barnett RA, Arteel GE, Beier JI. Vinyl chloride dysregulates metabolic homeostasis and enhances diet-induced liver injury in mice. Hepatol Commun 2018; 2:270-284. [PMID: 29507902 PMCID: PMC5831023 DOI: 10.1002/hep4.1151] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/19/2017] [Revised: 12/15/2017] [Accepted: 12/31/2017] [Indexed: 12/28/2022] Open
Abstract
Vinyl chloride (VC), a common industrial organochlorine and environmental pollutant, has been shown to directly cause hepatic angiosarcoma and toxicant‐associated steatohepatitis at high exposure levels. However, the impact of lower concentrations of VC on the progression of underlying liver diseases (e.g., nonalcoholic fatty liver disease [NAFLD]) is unclear. Given the high prevalence of NAFLD in the United States (and worldwide) population, this is an important concern. Recent studies by our group with VC metabolites suggest a potential interaction between VC exposure and underlying liver disease to cause enhanced damage. Here, a novel mouse model determined the effects of VC inhalation at levels below the current Occupational Safety and Health Administration limit (<1 ppm) in the context of NAFLD to better mimic human exposure and identify potential mechanisms of VC‐induced liver injury. VC exposure caused no overt liver injury in mice fed a low‐fat diet. However, in mice fed a high‐fat diet (HFD), VC significantly increased liver damage, steatosis, and increased neutrophil infiltration. Moreover, VC further enhanced HFD‐induced oxidative and endoplasmic reticulum stress. Importantly, VC exposure dysregulated energy homeostasis and impaired mitochondrial function, even in mice fed a low‐fat diet. In toto, the results indicate that VC exposure causes metabolic stress that sensitizes the liver to steatohepatitis caused by HFD. Conclusion: The hypothesis that low‐level (below the Occupational Safety and Health Administration limit) chronic exposure to VC by inhalation enhances liver injury caused by an HFD is supported. Importantly, our data raise concerns about the potential for overlap between fatty diets (i.e., Western diet) and exposure to VC and the health implications of this co‐exposure for humans. It also emphasizes that current safety restrictions may be insufficient to account for other factors that can influence hepatotoxicity. (Hepatology Communications 2018;2:270‐284)
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Affiliation(s)
- Anna L Lang
- Department of Pharmacology and Toxicology University of Louisville Health Sciences Center Louisville KY.,Hepatobiology and Toxicology Program University of Louisville Health Sciences Center Louisville KY.,University of Louisville Alcohol Research Center University of Louisville Health Sciences Center Louisville KY
| | - Liya Chen
- Department of Pharmacology and Toxicology University of Louisville Health Sciences Center Louisville KY.,Hepatobiology and Toxicology Program University of Louisville Health Sciences Center Louisville KY.,University of Louisville Alcohol Research Center University of Louisville Health Sciences Center Louisville KY
| | - Gavin D Poff
- Department of Pharmacology and Toxicology University of Louisville Health Sciences Center Louisville KY.,Hepatobiology and Toxicology Program University of Louisville Health Sciences Center Louisville KY
| | - Wen-Xing Ding
- Department of Pharmacology, Toxicology and Therapeutics University of Kansas Medical Center Kansas City KS
| | - Russel A Barnett
- Kentucky Institute for the Environment and Sustainable Development University of Louisville Louisville KY
| | - Gavin E Arteel
- Department of Pharmacology and Toxicology University of Louisville Health Sciences Center Louisville KY.,Hepatobiology and Toxicology Program University of Louisville Health Sciences Center Louisville KY.,University of Louisville Alcohol Research Center University of Louisville Health Sciences Center Louisville KY
| | - Juliane I Beier
- Department of Pharmacology and Toxicology University of Louisville Health Sciences Center Louisville KY.,Hepatobiology and Toxicology Program University of Louisville Health Sciences Center Louisville KY.,University of Louisville Alcohol Research Center University of Louisville Health Sciences Center Louisville KY
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83
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Honrath B, Culmsee C, Dolga AM. One protein, different cell fate: the differential outcome of depleting GRP75 during oxidative stress in neurons. Cell Death Dis 2018; 9:32. [PMID: 29348426 PMCID: PMC5833832 DOI: 10.1038/s41419-017-0148-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2017] [Revised: 11/13/2017] [Accepted: 11/14/2017] [Indexed: 12/30/2022]
Affiliation(s)
- Birgit Honrath
- Institute of Pharmacology and Clinical Pharmacy, University of Marburg, 35043, Marburg, Germany.
- Department of Molecular Pharmacology, Faculty of Science and Engineering, University of Groningen, 9713 AV, Groningen, The Netherlands.
| | - Carsten Culmsee
- Institute of Pharmacology and Clinical Pharmacy, University of Marburg, 35043, Marburg, Germany
| | - Amalia M Dolga
- Institute of Pharmacology and Clinical Pharmacy, University of Marburg, 35043, Marburg, Germany.
- Department of Molecular Pharmacology, Faculty of Science and Engineering, University of Groningen, 9713 AV, Groningen, The Netherlands.
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84
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Alsabeeh N, Chausse B, Kakimoto PA, Kowaltowski AJ, Shirihai O. Cell culture models of fatty acid overload: Problems and solutions. Biochim Biophys Acta Mol Cell Biol Lipids 2017; 1863:143-151. [PMID: 29155055 DOI: 10.1016/j.bbalip.2017.11.006] [Citation(s) in RCA: 72] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2017] [Revised: 11/09/2017] [Accepted: 11/14/2017] [Indexed: 12/17/2022]
Abstract
High plasma levels of fatty acids occur in a variety of metabolic diseases. Cellular effects of fatty acid overload resulting in negative cellular responses (lipotoxicity) are often studied in vitro, in an attempt to understand mechanisms involved in these diseases. Fatty acids are poorly soluble, and thus usually studied when complexed to albumins such as bovine serum albumin (BSA). The conjugation of fatty acids to albumin requires care pertaining to preparation of the solutions, effective free fatty acid concentrations, use of different fatty acid species, types of BSA, appropriate controls and ensuring cellular fatty acid uptake. This review discusses lipotoxicity models, the potential problems encountered when using these cellular models, as well as practical solutions for difficulties encountered.
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Affiliation(s)
- Nour Alsabeeh
- Department of Medicine, Division of Endocrinology, Diabetes and Hypertension, UCLA David Geffen School of Medicine, Los Angeles, CA 90095, USA; Department of Physiology and Biophysics, Boston University School of Medicine, Boston, MA 02118, USA; Department of Physiology, Faculty of Medicine, Kuwait University, Kuwait
| | - Bruno Chausse
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, SP 05508-000, Brazil
| | - Pamela A Kakimoto
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, SP 05508-000, Brazil
| | - Alicia J Kowaltowski
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, SP 05508-000, Brazil.
| | - Orian Shirihai
- Department of Medicine, Division of Endocrinology, Diabetes and Hypertension, UCLA David Geffen School of Medicine, Los Angeles, CA 90095, USA
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85
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Honrath B, Metz I, Bendridi N, Rieusset J, Culmsee C, Dolga AM. Glucose-regulated protein 75 determines ER-mitochondrial coupling and sensitivity to oxidative stress in neuronal cells. Cell Death Discov 2017; 3:17076. [PMID: 29367884 PMCID: PMC5672593 DOI: 10.1038/cddiscovery.2017.76] [Citation(s) in RCA: 94] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2017] [Revised: 09/01/2017] [Accepted: 09/04/2017] [Indexed: 01/20/2023] Open
Abstract
The crosstalk between different organelles allows for the exchange of proteins, lipids and ions. Endoplasmic reticulum (ER) and mitochondria are physically linked and signal through the mitochondria-associated membrane (MAM) to regulate the transfer of Ca2+ from ER stores into the mitochondrial matrix, thereby affecting mitochondrial function and intracellular Ca2+ homeostasis. The chaperone glucose-regulated protein 75 (GRP75) is a key protein expressed at the MAM interface which regulates ER–mitochondrial Ca2+ transfer. Previous studies revealed that modulation of GRP75 expression largely affected mitochondrial integrity and vulnerability to cell death. In the present study, we show that genetic ablation of GRP75, by weakening ER–mitochondrial junctions, provided protection against mitochondrial dysfunction and cell death in a model of glutamate-induced oxidative stress. Interestingly, GRP75 silencing attenuated both cytosolic and mitochondrial Ca2+ overload in conditions of oxidative stress, blocked the formation of reactive oxygen species and preserved mitochondrial respiration. These data revealed a major role for GRP75 in regulating mitochondrial function, Ca2+ and redox homeostasis. In line, GRP75 overexpression enhanced oxidative cell death induced by glutamate. Overall, our findings suggest weakening ER–mitochondrial connectivity by GRP75 inhibition as a novel protective approach in paradigms of oxidative stress in neuronal cells.
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Affiliation(s)
- Birgit Honrath
- Institute of Pharmacology and Clinical Pharmacy, University of Marburg, Marburg, Germany.,Faculty of Science and Engineering, Groningen Research Institute of Pharmacy (GRIP), Department of Molecular Pharmacology, University of Groningen, Groningen, The Netherlands
| | - Isabell Metz
- Institute of Pharmacology and Clinical Pharmacy, University of Marburg, Marburg, Germany
| | - Nadia Bendridi
- Laboratoire CarMeN, INSERM U1060, INRA U1235, Lyon University, Université Claude Bernard Lyon1, INSA-Lyon, Oullins, France
| | - Jennifer Rieusset
- Laboratoire CarMeN, INSERM U1060, INRA U1235, Lyon University, Université Claude Bernard Lyon1, INSA-Lyon, Oullins, France
| | - Carsten Culmsee
- Institute of Pharmacology and Clinical Pharmacy, University of Marburg, Marburg, Germany
| | - Amalia M Dolga
- Institute of Pharmacology and Clinical Pharmacy, University of Marburg, Marburg, Germany.,Faculty of Science and Engineering, Groningen Research Institute of Pharmacy (GRIP), Department of Molecular Pharmacology, University of Groningen, Groningen, The Netherlands
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86
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High fat diet disrupts endoplasmic reticulum calcium homeostasis in the rat liver. J Hepatol 2017; 67:1009-1017. [PMID: 28596111 PMCID: PMC6122848 DOI: 10.1016/j.jhep.2017.05.023] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/02/2016] [Revised: 05/10/2017] [Accepted: 05/25/2017] [Indexed: 12/14/2022]
Abstract
BACKGROUND & AIMS Disruption to endoplasmic reticulum (ER) calcium homeostasis has been implicated in obesity, however, the ability to longitudinally monitor ER calcium fluctuations has been challenging with prior methodologies. We recently described the development of a Gaussia luciferase (GLuc)-based reporter protein responsive to ER calcium depletion (GLuc-SERCaMP) and investigated the effect of a high fat diet on ER calcium homeostasis. METHODS A GLuc-based reporter cell line was treated with palmitate, a free fatty acid. Rats intrahepatically injected with GLuc-SERCaMP reporter were fed a cafeteria diet or high fat diet. The liver and plasma were examined for established markers of steatosis and compared to plasma levels of SERCaMP activity. RESULTS Palmitate induced GLuc-SERCaMP release in vitro, indicating ER calcium depletion. Consumption of a cafeteria diet or high fat pellets correlated with alterations to hepatic ER calcium homeostasis in rats, shown by increased GLuc-SERCaMP release. Access to ad lib high fat pellets also led to a corresponding decrease in microsomal calcium ATPase activity and an increase in markers of hepatic steatosis. In addition to GLuc-SERCaMP, we have also identified endogenous proteins (endogenous SERCaMPs) with a similar response to ER calcium depletion. We demonstrated the release of an endogenous SERCaMP, thought to be a liver esterase, during access to a high fat diet. Attenuation of both GLuc-SERCaMP and endogenous SERCaMP was observed during dantrolene administration. CONCLUSIONS Here we describe the use of a reporter for in vitro and in vivo models of high fat diet. Our results support the theory that dietary fat intake correlates with a decrease in ER calcium levels in the liver and suggest a high fat diet alters the ER proteome. Lay summary: ER calcium dysregulation was observed in rats fed a cafeteria diet or high fat pellets, with fluctuations in sensor release correlating with fat intake. Attenuation of sensor release, as well as food intake was observed during administration of dantrolene, a drug that stabilizes ER calcium. The study describes a novel technique for liver research and provides insight into cellular processes that may contribute to the pathogenesis of obesity and fatty liver disease.
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87
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Colvin BN, Longtine MS, Chen B, Costa ML, Nelson DM. Oleate attenuates palmitate-induced endoplasmic reticulum stress and apoptosis in placental trophoblasts. Reproduction 2017; 153:369-380. [PMID: 28159805 DOI: 10.1530/rep-16-0576] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2016] [Revised: 12/02/2016] [Accepted: 01/03/2017] [Indexed: 12/24/2022]
Abstract
Pre-pregnancy obesity is increasingly common and predisposes pregnant women and offspring to gestational diabetes, pre-eclampsia, fetal growth abnormalities and stillbirth. Obese women exhibit elevated levels of the two most common dietary fatty acids, palmitate and oleate, and the maternal blood containing these nutrients bathes the surface of trophoblasts of placental villi in vivo We test the hypothesis that the composition and concentration of free fatty acids modulate viability and function of primary human villous trophoblasts in culture. We found that palmitate increases syncytiotrophoblast death, specifically by caspase-mediated apoptosis, whereas oleate does not cause enhanced cell death. Importantly, exposure to both fatty acids in equimolar amounts yielded no increase in death or apoptosis, suggesting that oleate can protect syncytiotrophoblasts from palmitate-induced death. We further found that palmitate, but not oleate or oleate with palmitate, increases endoplasmic reticulum (ER) stress, signaling through the unfolded protein response, and yielding CHOP-mediated induction of apoptosis. Finally, we show that oleate or oleate plus palmitate both lead to increased lipid droplets in syncytiotrophoblasts, whereas palmitate does not. The data show palmitate is toxic to human syncytiotrophoblasts, through the induction of ER stress and apoptosis mediated by CHOP, whereas oleate is not toxic, abrogates palmitate toxicity and induces fat accumulation. We speculate that our in vitro results offer pathways by which the metabolic milieu of the obese pregnant woman can yield villous trophoblast dysfunction and sub-optimal placental function.
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Affiliation(s)
| | - Mark S Longtine
- Department of Obstetrics and GynecologyWashington University School of Medicine, St Louis, Missouri, USA
| | - Baosheng Chen
- Department of Obstetrics and GynecologyWashington University School of Medicine, St Louis, Missouri, USA
| | - Maria Laura Costa
- Department of Obstetrics and GynecologyWashington University School of Medicine, St Louis, Missouri, USA.,Department of Obstetrics and GynecologyUniversidade Estadual de Campinas, Cidade Universitaria Zeferino Vaz, Campinas, Brazil
| | - D Michael Nelson
- Department of Obstetrics and GynecologyWashington University School of Medicine, St Louis, Missouri, USA
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88
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Penke M, Schuster S, Gorski T, Gebhardt R, Kiess W, Garten A. Oleate ameliorates palmitate-induced reduction of NAMPT activity and NAD levels in primary human hepatocytes and hepatocarcinoma cells. Lipids Health Dis 2017; 16:191. [PMID: 28974242 PMCID: PMC5627432 DOI: 10.1186/s12944-017-0583-6] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2017] [Accepted: 09/26/2017] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Nicotinamide phosphoribosyltransferase (NAMPT) and nicotinamide adenine dinucleotide (NAD) levels are crucial for liver function. The saturated fatty acid palmitate and the unsaturated fatty acid oleate are the main free fatty acids in adipose tissue and human diet. We asked how these fatty acids affect cell survival, NAMPT and NAD levels in HepG2 cells and primary human hepatocytes. METHODS HepG2 cells were stimulated with palmitate (0.5mM), oleate (1mM) or a combination of both (0.5mM/1mM) as well as nicotinamide mononucleotide (NMN) (0.5 mM) or the specific NAMPT inhibitor FK866 (10nM). Cell survival was measured by WST-1 assay and Annexin V/propidium iodide staining. NAD levels were determined by NAD/NADH Assay or HPLC. Protein and mRNA levels were analysed by Western blot analyses and qPCR, respectively. NAMPT enzyme activity was measured using radiolabelled 14C-nicotinamide. Lipids were stained by Oil red O staining. RESULTS Palmitate significantly reduced cell survival and induced apoptosis at physiological doses. NAMPT activity and NAD levels significantly declined after 48h of palmitate. In addition, NAMPT mRNA expression was enhanced which was associated with increased NAMPT release into the supernatant, while intracellular NAMPT protein levels remained stable. Oleate alone did not influence cell viability and NAMPT activity but ameliorated the negative impact of palmitate on cell survival, NAMPT activity and NAD levels, as well as the increased NAMPT mRNA expression and secretion. NMN was able to normalize intracellular NAD levels but did not ameliorate cell viability after co-stimulation with palmitate. FK866, a specific NAMPT inhibitor did not influence lipid accumulation after oleate-treatment. CONCLUSIONS Palmitate targets NAMPT activity with a consequent cellular depletion of NAD. Oleate protects from palmitate-induced apoptosis and variation of NAMPT and NAD levels. Palmitate-induced cell stress leads to an increase of NAMPT mRNA and accumulation in the supernatant. However, the proapoptotic action of palmitate seems not to be mediated by decreased NAD levels.
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Affiliation(s)
- Melanie Penke
- Center for Pediatric Research Leipzig (CPL), University Hospital for Children & Adolescents, University of Leipzig, Liebigstraße 21, 04103 Leipzig, Germany
| | - Susanne Schuster
- Center for Pediatric Research Leipzig (CPL), University Hospital for Children & Adolescents, University of Leipzig, Liebigstraße 21, 04103 Leipzig, Germany
| | - Theresa Gorski
- Center for Pediatric Research Leipzig (CPL), University Hospital for Children & Adolescents, University of Leipzig, Liebigstraße 21, 04103 Leipzig, Germany
| | - Rolf Gebhardt
- Institute of Biochemistry, Faculty of Medicine, University of Leipzig, Johannisallee 30, 04103 Leipzig, Germany
| | - Wieland Kiess
- Center for Pediatric Research Leipzig (CPL), University Hospital for Children & Adolescents, University of Leipzig, Liebigstraße 21, 04103 Leipzig, Germany
| | - Antje Garten
- Center for Pediatric Research Leipzig (CPL), University Hospital for Children & Adolescents, University of Leipzig, Liebigstraße 21, 04103 Leipzig, Germany
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89
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Chemaly ER, Troncone L, Lebeche D. SERCA control of cell death and survival. Cell Calcium 2017; 69:46-61. [PMID: 28747251 DOI: 10.1016/j.ceca.2017.07.001] [Citation(s) in RCA: 132] [Impact Index Per Article: 18.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2017] [Revised: 07/03/2017] [Accepted: 07/03/2017] [Indexed: 12/31/2022]
Abstract
Intracellular calcium (Ca2+) is a critical coordinator of various aspects of cellular physiology. It is increasingly apparent that changes in cellular Ca2+ dynamics contribute to the regulation of normal and pathological signal transduction that controls cell growth and survival. Aberrant perturbations in Ca2+ homeostasis have been implicated in a range of pathological conditions, such as cardiovascular diseases, diabetes, tumorigenesis and steatosis hepatitis. Intracellular Ca2+ concentrations are therefore tightly regulated by a number of Ca2+ handling enzymes, proteins, channels and transporters located in the plasma membrane and in Ca2+ storage organelles, which work in concert to fine tune a temporally and spatially precise Ca2+ signal. Chief amongst them is the sarco/endoplasmic reticulum (SR/ER) Ca2+ ATPase pump (SERCA) which actively re-accumulates released Ca2+ back into the SR/ER, therefore maintaining Ca2+ homeostasis. There are at least 14 different SERCA isoforms encoded by three ATP2A1-3 genes whose expressions are species- and tissue-specific. Altered SERCA expression and activity results in cellular malignancy and induction of ER stress and ER stress-associated apoptosis. The role of SERCA misregulation in the control of apoptosis in various cell types and disease setting with prospective therapeutic implications is the focus of this review. Ca2+ is a double edge sword for both life as well as death, and current experimental evidence supports a model in which Ca2+ homeostasis and SERCA activity represent a nodal point that controls cell survival. Pharmacological or genetic targeting of this axis constitutes an incredible therapeutic potential to treat different diseases sharing similar biological disorders.
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Affiliation(s)
- Elie R Chemaly
- Division of Nephrology and Hypertension, Department of Medicine, Morsani College of Medicine, University of South Florida, Tampa, FL, USA
| | - Luca Troncone
- Cardiovascular Research Institute, Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Djamel Lebeche
- Cardiovascular Research Institute, Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, New York, USA; Diabetes, Obesity and Metabolism Institute, Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, New York, USA; Graduate School of Biological Sciences, Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, New York, USA.
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90
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Honrath B, Krabbendam IE, Culmsee C, Dolga AM. Small conductance Ca 2+-activated K + channels in the plasma membrane, mitochondria and the ER: Pharmacology and implications in neuronal diseases. Neurochem Int 2017; 109:13-23. [PMID: 28511953 DOI: 10.1016/j.neuint.2017.05.005] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2017] [Revised: 04/24/2017] [Accepted: 05/08/2017] [Indexed: 12/14/2022]
Abstract
Ca2+-activated K+ (KCa) channels regulate after-hyperpolarization in many types of neurons in the central and peripheral nervous system. Small conductance Ca2+-activated K+ (KCa2/SK) channels, a subfamily of KCa channels, are widely expressed in the nervous system, and in the cardiovascular system. Voltage-independent SK channels are activated by alterations in intracellular Ca2+ ([Ca2+]i) which facilitates the opening of these channels through binding of Ca2+ to calmodulin that is constitutively bound to the SK2 C-terminus. In neurons, SK channels regulate synaptic plasticity and [Ca2+]i homeostasis, and a number of recent studies elaborated on the emerging neuroprotective potential of SK channel activation in conditions of excitotoxicity and cerebral ischemia, as well as endoplasmic reticulum (ER) stress and oxidative cell death. Recently, SK channels were discovered in the inner mitochondrial membrane and in the membrane of the endoplasmic reticulum which sheds new light on the underlying molecular mechanisms and pathways involved in SK channel-mediated protective effects. In this review, we will discuss the protective properties of pharmacological SK channel modulation with particular emphasis on intracellularly located SK channels as potential therapeutic targets in paradigms of neuronal dysfunction.
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Affiliation(s)
- Birgit Honrath
- Institute of Pharmacology and Clinical Pharmacy, University of Marburg, 35043 Marburg, Germany; Faculty of Science and Engineering, Groningen Research Institute of Pharmacy, Department of Molecular Pharmacology, University of Groningen, 9713 AV Groningen, The Netherlands
| | - Inge E Krabbendam
- Faculty of Science and Engineering, Groningen Research Institute of Pharmacy, Department of Molecular Pharmacology, University of Groningen, 9713 AV Groningen, The Netherlands
| | - Carsten Culmsee
- Institute of Pharmacology and Clinical Pharmacy, University of Marburg, 35043 Marburg, Germany
| | - Amalia M Dolga
- Institute of Pharmacology and Clinical Pharmacy, University of Marburg, 35043 Marburg, Germany; Faculty of Science and Engineering, Groningen Research Institute of Pharmacy, Department of Molecular Pharmacology, University of Groningen, 9713 AV Groningen, The Netherlands.
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91
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Sodium 4-phenylbutyric acid prevents murine acetaminophen hepatotoxicity by minimizing endoplasmic reticulum stress. J Gastroenterol 2017; 52:611-622. [PMID: 27599972 DOI: 10.1007/s00535-016-1256-3] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/04/2016] [Accepted: 08/26/2016] [Indexed: 02/06/2023]
Abstract
BACKGROUND Acetaminophen (APAP) overdose induces severe oxidative stress followed by hepatocyte apoptosis/necrosis. Previous studies have indicated that endoplasmic reticulum (ER) stress is involved in the cell death process. Therefore, we investigated the effect of the chemical chaperone 4-phenyl butyric acid (PBA) on APAP-induced liver injury in mice. METHODS Eight-week-old male C57Bl6/J mice were given a single intraperitoneal (i.p.) injection of APAP (450 mg/kg body weight), following which some were repeatedly injected with PBA (120 mg/kg body weight, i.p.) every 3 h starting at 0.5 h after the APAP challenge. All mice were then serially euthanized up to 12 h later. RESULTS PBA treatment dramatically ameliorated the massive hepatocyte apoptosis/necrosis that was observed 6 h after APAP administration. PBA also significantly prevented the APAP-induced increases in cleaved activating transcription factor 6 and phosphorylation of c-Jun N-terminal protein kinase and significantly blunted the increases in mRNA levels for binding immunoglobulin protein, spliced X-box binding protein-1, and C/EBP homologous protein. Moreover, PBA significantly prevented APAP-induced Bax translocation to the mitochondria, and the expression of heme oxygenase-1 mRNA and 4-hydroxynonenal. By contrast, PBA did not affect hepatic glutathione depletion following APAP administration, reflecting APAP metabolism. CONCLUSIONS PBA prevents APAP-induced liver injury even when an APAP challenge precedes its administration. The underlying mechanism of action most likely involves the prevention of ER stress-induced apoptosis/necrosis in the hepatocytes during APAP intoxication.
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92
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Li X, Li X, Lu J, Huang Y, Lv L, Luan Y, Liu R, Sun R. Saikosaponins induced hepatotoxicity in mice via lipid metabolism dysregulation and oxidative stress: a proteomic study. Altern Ther Health Med 2017; 17:219. [PMID: 28420359 PMCID: PMC5395759 DOI: 10.1186/s12906-017-1733-0] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2017] [Accepted: 04/07/2017] [Indexed: 02/08/2023]
Abstract
BACKGROUND Radix Bupleuri (RB) has been popularly used for treating many liver diseases such as chronic hepatic inflammation and viral Hepatitis in China. Increasing clinical and experimental evidence indicates the potential hepatotoxicity of RB or prescriptions containing RB. Recently, Saikosaponins (SS) have been identified as major bioactive compounds isolated from RB, which may be also responsible for RB-induced liver injury. METHODS Serum AST, ALT and LDH levels were determined to evaluate SS-induced liver injury in mice. Serum and liver total triglyceride and cholesterol were used to indicate lipid metabolism homeostasis. Liver ROS, GSH, MDA and iNOS were used to examine the oxidative stress level after SS administration. Western blot was used to detect CYP2E1 expression. A 8-Plex iTRAQ Labeling Coupled with 2D LC - MS/MS technique was applied to analyze the protein expression profiles in livers of mice administered with different doses of SS for different time periods. Gene ontology analysis, cluster and enrichment analysis were employed to elucidate potential mechanism involved. HepG2 cells were used to identify our findings in vitro. RESULTS SS dose- and time-dependently induced liver injury in mice, indicated by increased serum AST, ALT and LDH levels. According to proteomic analysis, 487 differentially expressed proteins were identified in mice administrated with different dose of SS for different time periods. Altered proteins were enriched in pathways such as lipid metabolism, protein metabolism, macro molecular transportation, cytoskeleton structure and response to stress. SS enhanced CYP2E1 expression in a time and dose dependent manner, and induced oxidative stress both in vivo and in vitro. CONCLUSION Our results identified hepatotoxicity and established dose-time course-liver toxicity relationship in mice model of SS administration and suggested potential mechanisms, including impaired lipid and protein metabolism and oxidative stress. The current study provides experimental evidence for clinical safe use of RB, and also new insights into understanding the mechanism by which SS and RB induced liver injury.
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93
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Mann JP, Raponi M, Nobili V. Clinical implications of understanding the association between oxidative stress and pediatric NAFLD. Expert Rev Gastroenterol Hepatol 2017; 11:371-382. [PMID: 28162008 DOI: 10.1080/17474124.2017.1291340] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Oxidative stress is central to the pathogenesis of non-alcoholic steatohepatitis. The reactive oxygen species (ROS) that characterise oxidative stress are generated in several cellular sites and their production is influence by multi-organ interactions. Areas covered: Mitochondrial dysfunction is the main source of ROS in fatty liver and is closely related to endoplasmic reticulum stress. Both are caused by lipotoxicity and together these three factors form a cycle of progressive organelle damage, resulting in sterile inflammation and apoptosis. Adipose tissue inflammation and intestinal dysbiosis provide substrates for ROS formation and trigger immune activation. Obstructive sleep apnea and abnormal divalent metal metabolism may also play a role. Expert commentary: The majority of available high-quality data originates from studies in adults and there are fewer therapeutic trials performed in pediatric cohorts, therefore conclusions are generalised to children. Establishing the role of organelle interactions, and its relationship with oxidative stress in steatohepatitis, is a rapidly evolving area of research.
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Affiliation(s)
- Jake P Mann
- a Metabolic Research Laboratories, Institute of Metabolic Science , University of Cambridge , Cambridge , UK.,b Department of paediatrics , University of Cambridge , Cambridge , UK
| | | | - Valerio Nobili
- d Hepatometabolic Unit , Bambino Gesu Hospital - IRCCS , Rome , Italy.,e Liver Research Unit , Bambino Gesu Hospital - IRCCS , Rome , Italy
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94
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Dong Y, Fernandes C, Liu Y, Wu Y, Wu H, Brophy ML, Deng L, Song K, Wen A, Wong S, Yan D, Towner R, Chen H. Role of endoplasmic reticulum stress signalling in diabetic endothelial dysfunction and atherosclerosis. Diab Vasc Dis Res 2017; 14:14-23. [PMID: 27941052 PMCID: PMC5161113 DOI: 10.1177/1479164116666762] [Citation(s) in RCA: 68] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
It is well established that diabetes mellitus accelerates atherosclerotic vascular disease. Endothelial injury has been proposed to be the initial event in the pathogenesis of atherosclerosis. Endothelium not only acts as a semi-selective barrier but also serves physiological and metabolic functions. Diabetes or high glucose in circulation triggers a series of intracellular responses and organ damage such as endothelial dysfunction and apoptosis. One such response is high glucose-induced chronic endoplasmic reticulum stress in the endothelium. The unfolded protein response is an acute reaction that enables cells to overcome endoplasmic reticulum stress. However, when chronically persistent, endoplasmic reticulum stress response could ultimately lead to endothelial dysfunction and atherosclerosis. Herein, we discuss the scientific advances in understanding endoplasmic reticulum stress-induced endothelial dysfunction, the pathogenesis of diabetes-accelerated atherosclerosis and endoplasmic reticulum stress as a potential target in therapies for diabetic atherosclerosis.
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Affiliation(s)
- Yunzhou Dong
- Vascular Biology Program, Department of Surgery, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | | | - Yanjun Liu
- Department of Internal Medicine, Charles R. Drew University of Medicine and Science, University of California-Los Angeles School of Medicine, Los Angeles, CA, USA
| | - Yong Wu
- Department of Internal Medicine, Charles R. Drew University of Medicine and Science, University of California-Los Angeles School of Medicine, Los Angeles, CA, USA
| | - Hao Wu
- Vascular Biology Program, Department of Surgery, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Megan L Brophy
- Vascular Biology Program, Department of Surgery, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Lin Deng
- Department of Biological Chemistry & Molecular Pharmacology, Harvard Medical School, Boston, MA, USA
| | - Kai Song
- Vascular Biology Program, Department of Surgery, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Aiyun Wen
- Vascular Biology Program, Department of Surgery, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Scott Wong
- Vascular Biology Program, Department of Surgery, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Daoguang Yan
- Department of Biology, Jinan University, Guangzhou, China
| | - Rheal Towner
- Advanced Magnetic Resonance Center, Oklahoma Medical Research Foundation, Oklahoma, OK, USA
| | - Hong Chen
- Vascular Biology Program, Department of Surgery, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
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95
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Metabolic Disorders and Cancer: Hepatocyte Store-Operated Ca2+ Channels in Nonalcoholic Fatty Liver Disease. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2017; 993:595-621. [DOI: 10.1007/978-3-319-57732-6_30] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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96
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Abstract
Hepatic steatosis, the first step in the progression of nonalcoholic fatty liver disease, is characterized by triglyceride accumulation in hepatocytes and is highly prevalent in people with obesity. Although initially asymptomatic, hepatic steatosis is an important risk factor for the development of hepatic insulin resistance and type 2 diabetes mellitus and can also progress to more severe pathologies such as nonalcoholic steatohepatitis, liver fibrosis and cirrhosis; hepatic steatosis has, therefore, received considerable research interest in the past 20 years. The lipid accumulation that defines hepatic steatosis disturbs the function of the endoplasmic reticulum (ER) in hepatocytes, thereby generating chronic ER stress that interferes with normal cellular function. Although ubiquitous stress response mechanisms (namely, ER-associated degradation, unfolded protein response and autophagy) are the main processes for restoring cellular proteostasis, these mechanisms are unable to alleviate ER stress in the context of the fatty liver. Furthermore, ER stress and ER stress responses can promote lipid accumulation in hepatocytes in a counter-productive manner and could, therefore, be the origin of a vicious pathological cycle.
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Affiliation(s)
- Andrei Baiceanu
- Institut National de la Santé et de la Recherche Médicale, UMRS 1138, Centre de Recherche des Cordeliers, F-75006, Paris, France
- Sorbonne Universités, UPMC Univ Paris 06, UMRS 1138, Centre de Recherche des Cordeliers, F-75006, Paris, France
- Université Paris Descartes, Sorbonne Paris Cité, UMRS 1138, Centre de Recherche des Cordeliers, 15 rue de l'école de médecine, F-75006, Paris, France
- University of Medicine and Pharmacy Iuliu Hat¸ieganu, Faculty of Pharmacy, 8 Victor Babes Street, 400012 Cluj-Napoca, Romania
| | - Pierre Mesdom
- Institut National de la Santé et de la Recherche Médicale, UMRS 1138, Centre de Recherche des Cordeliers, F-75006, Paris, France
- Sorbonne Universités, UPMC Univ Paris 06, UMRS 1138, Centre de Recherche des Cordeliers, F-75006, Paris, France
- Université Paris Descartes, Sorbonne Paris Cité, UMRS 1138, Centre de Recherche des Cordeliers, 15 rue de l'école de médecine, F-75006, Paris, France
| | - Marie Lagouge
- Institut National de la Santé et de la Recherche Médicale, UMRS 1138, Centre de Recherche des Cordeliers, F-75006, Paris, France
- Sorbonne Universités, UPMC Univ Paris 06, UMRS 1138, Centre de Recherche des Cordeliers, F-75006, Paris, France
- Université Paris Descartes, Sorbonne Paris Cité, UMRS 1138, Centre de Recherche des Cordeliers, 15 rue de l'école de médecine, F-75006, Paris, France
| | - Fabienne Foufelle
- Institut National de la Santé et de la Recherche Médicale, UMRS 1138, Centre de Recherche des Cordeliers, F-75006, Paris, France
- Sorbonne Universités, UPMC Univ Paris 06, UMRS 1138, Centre de Recherche des Cordeliers, F-75006, Paris, France
- Université Paris Descartes, Sorbonne Paris Cité, UMRS 1138, Centre de Recherche des Cordeliers, 15 rue de l'école de médecine, F-75006, Paris, France
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97
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Hu S, Wang J, Wang J, Xue C, Wang Y. Long-chain bases from sea cucumber mitigate endoplasmic reticulum stress and inflammation in obesity mice. J Food Drug Anal 2016; 25:628-636. [PMID: 28911649 PMCID: PMC9328807 DOI: 10.1016/j.jfda.2016.10.011] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2016] [Revised: 10/09/2016] [Accepted: 10/17/2016] [Indexed: 01/01/2023] Open
Abstract
Endoplasmic reticulum (ER) stress and inflammation can induce hyperglycemia. Long-chain bases (LCBs) from sea cucumber exhibit antihyperglycemic activities. However, their effects on ER stress and inflammation are unknown. We investigated the effects of LCBs on ER stress and inflammatory response in high-fat, fructose diet-induced obesity mice. Reactive oxygen species and free fatty acids were measured. Inflammatory cytokines in serum and their mRNA expressions in epididymal adipose tissues were investigated. Hepatic ER stress-related key genes were detected. c-Jun NH2-terminal kinase and nuclear factor κB inflammatory pathways were also evaluated in the liver. Results showed that LCBs reduced serum and hepatic reactive oxygen species and free fatty acids concentrations. LCBs decreased serum proinflammatory cytokines levels, namely interleukin (IL)-1β, tumor necrosis factor-α, IL-6, macrophage inflammatory protein 1, and c-reactive protein, and increased anti-inflammatory cytokine IL-10 concentration. The mRNA and protein expressions of these cytokines in epididymal adipose tissues were regulated by LCBs as similar to their circulatory contents. LCBs inhibited phosphorylated c-Jun NH2-terminal kinase and inhibitor κ kinase β, and nuclear factor κB nuclear translocation. LCBs also inhibited mRNA expression of ER stress markers glucose regulated protein, activating transcription factor 6, double-stranded RNA-activated protein kinase-like endoplasmic reticulum kinase, and X-box binding protein 1, and phosphorylation of eukaryotic initiation factor-α and inositol requiring enzyme 1α. These results indicate that LCBs can alleviate ER stress and inflammatory response. Nutritional supplementation with LCBs may offer an adjunctive therapy for RE stress-associated inflammation.
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Affiliation(s)
- Shiwei Hu
- Innovation Application Institute, Zhejiang Ocean University, Zhoushan, Zhejiang Province, China; College of Food Science and Engineering, Ocean University of China, Qingdao, Shandong Province, China.
| | - Jinhui Wang
- Innovation Application Institute, Zhejiang Ocean University, Zhoushan, Zhejiang Province, China
| | - Jingfeng Wang
- College of Food Science and Engineering, Ocean University of China, Qingdao, Shandong Province, China
| | - Changhu Xue
- College of Food Science and Engineering, Ocean University of China, Qingdao, Shandong Province, China
| | - Yuming Wang
- College of Food Science and Engineering, Ocean University of China, Qingdao, Shandong Province, China
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98
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Feriod CN, Oliveira AG, Guerra MT, Nguyen L, Richards KM, Jurczak MJ, Ruan HB, Camporez JP, Yang X, Shulman GI, Bennett AM, Nathanson MH, Ehrlich BE. Hepatic Inositol 1,4,5 Trisphosphate Receptor Type 1 Mediates Fatty Liver. Hepatol Commun 2016; 1:23-35. [PMID: 28966992 PMCID: PMC5613674 DOI: 10.1002/hep4.1012] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Fatty liver is the most common type of liver disease, affecting nearly one third of the US population and more than half a billion people worldwide. Abnormalities in ER calcium handling and mitochondrial function each have been implicated in abnormal lipid droplet formation. Here we show that the type 1 isoform of the inositol 1,4,5-trisphosphate receptor (InsP3R1) specifically links ER calcium release to mitochondrial calcium signaling and lipid droplet formation in hepatocytes. Moreover, liver-specific InsP3R1 knockout mice have impaired mitochondrial calcium signaling, decreased hepatic triglycerides, reduced lipid droplet formation and are resistant to development of fatty liver. Patients with non-alcoholic steatohepatitis, the most malignant form of fatty liver, have increased hepatic expression of InsP3R1 and the extent of ER-mitochondrial co-localization correlates with the degree of steatosis in human liver biopsies. CONCLUSION InsP3R1 plays a central role in lipid droplet formation in hepatocytes and the data suggest that it is involved in the development of human fatty liver disease.
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Affiliation(s)
- Colleen N Feriod
- Department of Cellular and Molecular Physiology, Yale University School of Medicine New Haven, CT 06520.,Department of Pharmacology, Yale University School of Medicine New Haven, CT 06520
| | - Andre Gustavo Oliveira
- Section of Digestive Diseases, Internal Medicine, Yale University School of Medicine New Haven, CT 06520
| | - Mateus T Guerra
- Section of Digestive Diseases, Internal Medicine, Yale University School of Medicine New Haven, CT 06520
| | - Lily Nguyen
- Department of Pharmacology, Yale University School of Medicine New Haven, CT 06520
| | | | - Michael J Jurczak
- Department of Internal Medicine, Yale University School of Medicine New Haven, CT 06520
| | - Hai-Bin Ruan
- Department of Comparative Medicine, Yale University School of Medicine New Haven, CT 06520.,Program in Integrative Cell Signaling and Neurobiology of Metabolism, Yale University School of Medicine New Haven, CT 06520
| | - Joao Paulo Camporez
- Department of Internal Medicine, Yale University School of Medicine New Haven, CT 06520
| | - Xiaoyong Yang
- Department of Cellular and Molecular Physiology, Yale University School of Medicine New Haven, CT 06520.,Department of Comparative Medicine, Yale University School of Medicine New Haven, CT 06520.,Program in Integrative Cell Signaling and Neurobiology of Metabolism, Yale University School of Medicine New Haven, CT 06520
| | - Gerald I Shulman
- Department of Cellular and Molecular Physiology, Yale University School of Medicine New Haven, CT 06520.,Department of Internal Medicine, Yale University School of Medicine New Haven, CT 06520.,Howard Hughes Medical Institute, Yale University School of Medicine New Haven, CT 06520
| | - Anton M Bennett
- Department of Pharmacology, Yale University School of Medicine New Haven, CT 06520.,Program in Integrative Cell Signaling and Neurobiology of Metabolism, Yale University School of Medicine New Haven, CT 06520
| | - Michael H Nathanson
- Section of Digestive Diseases, Internal Medicine, Yale University School of Medicine New Haven, CT 06520
| | - Barbara E Ehrlich
- Department of Cellular and Molecular Physiology, Yale University School of Medicine New Haven, CT 06520.,Department of Pharmacology, Yale University School of Medicine New Haven, CT 06520
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99
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Martínez L, Torres S, Baulies A, Alarcón-Vila C, Elena M, Fabriàs G, Casas J, Caballeria J, Fernandez-Checa JC, García-Ruiz C. Myristic acid potentiates palmitic acid-induced lipotoxicity and steatohepatitis associated with lipodystrophy by sustaning de novo ceramide synthesis. Oncotarget 2016; 6:41479-96. [PMID: 26539645 PMCID: PMC4747168 DOI: 10.18632/oncotarget.6286] [Citation(s) in RCA: 66] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2015] [Accepted: 10/23/2015] [Indexed: 12/19/2022] Open
Abstract
Palmitic acid (PA) induces hepatocyte apoptosis and fuels de novo ceramide synthesis in the endoplasmic reticulum (ER). Myristic acid (MA), a free fatty acid highly abundant in copra/palmist oils, is a predictor of nonalcoholic steatohepatitis (NASH) and stimulates ceramide synthesis. Here we investigated the synergism between MA and PA in ceramide synthesis, ER stress, lipotoxicity and NASH. Unlike PA, MA is not lipotoxic but potentiated PA-mediated lipoapoptosis, ER stress, caspase-3 activation and cytochrome c release in primary mouse hepatocytes (PMH). Moreover, MA kinetically sustained PA-induced total ceramide content by stimulating dehydroceramide desaturase and switched the ceramide profile from decreased to increased ceramide 14:0/ceramide16:0, without changing medium and long-chain ceramide species. PMH were more sensitive to equimolar ceramide14:0/ceramide16:0 exposure, which mimics the outcome of PA plus MA treatment on ceramide homeostasis, than to either ceramide alone. Treatment with myriocin to inhibit ceramide synthesis and tauroursodeoxycholic acid to prevent ER stress ameliorated PA plus MA induced apoptosis, similar to the protection afforded by the antioxidant BHA, the pan-caspase inhibitor z-VAD-Fmk and JNK inhibition. Moreover, ruthenium red protected PMH against PA and MA-induced cell death. Recapitulating in vitro findings, mice fed a diet enriched in PA plus MA exhibited lipodystrophy, hepatosplenomegaly, increased liver ceramide content and cholesterol levels, ER stress, liver damage, inflammation and fibrosis compared to mice fed diets enriched in PA or MA alone. The deleterious effects of PA plus MA-enriched diet were largely prevented by in vivo myriocin treatment. These findings indicate a causal link between ceramide synthesis and ER stress in lipotoxicity, and imply that the consumption of diets enriched in MA and PA can cause NASH associated with lipodystrophy.
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Affiliation(s)
- Laura Martínez
- Cell Death and Proliferation, Institute of Biomedical Research of Barcelona (IIBB), CSIC, Barcelona, Spain.,Liver Unit, Hospital Clinic I Provincial de Barcelona, IDIBAPS and CIBERehd, Barcelona, Spain
| | - Sandra Torres
- Cell Death and Proliferation, Institute of Biomedical Research of Barcelona (IIBB), CSIC, Barcelona, Spain.,Liver Unit, Hospital Clinic I Provincial de Barcelona, IDIBAPS and CIBERehd, Barcelona, Spain
| | - Anna Baulies
- Cell Death and Proliferation, Institute of Biomedical Research of Barcelona (IIBB), CSIC, Barcelona, Spain.,Liver Unit, Hospital Clinic I Provincial de Barcelona, IDIBAPS and CIBERehd, Barcelona, Spain
| | - Cristina Alarcón-Vila
- Cell Death and Proliferation, Institute of Biomedical Research of Barcelona (IIBB), CSIC, Barcelona, Spain.,Liver Unit, Hospital Clinic I Provincial de Barcelona, IDIBAPS and CIBERehd, Barcelona, Spain
| | - Montserrat Elena
- Biomedic Diagnosis Center, Hospital Clinic i Provincial de Barcelona, IDIBAPS, Barcelona, Spain
| | - Gemma Fabriàs
- Research Unit on BioActive Molecules (RUBAM), Departament de Química Orgànica Biològica, Institut d'Investigacions Químiques i Ambientals de Barcelona, Consejo Superior de Investigaciones Científicas (CSIC), Barcelona, Spain
| | - Josefina Casas
- Research Unit on BioActive Molecules (RUBAM), Departament de Química Orgànica Biològica, Institut d'Investigacions Químiques i Ambientals de Barcelona, Consejo Superior de Investigaciones Científicas (CSIC), Barcelona, Spain
| | - Joan Caballeria
- Liver Unit, Hospital Clinic I Provincial de Barcelona, IDIBAPS and CIBERehd, Barcelona, Spain
| | - Jose C Fernandez-Checa
- Cell Death and Proliferation, Institute of Biomedical Research of Barcelona (IIBB), CSIC, Barcelona, Spain.,Liver Unit, Hospital Clinic I Provincial de Barcelona, IDIBAPS and CIBERehd, Barcelona, Spain.,Research Center for ALPD, Keck School of Medicine, Univerisity of Southern California, Los Angeles, CA, USA
| | - Carmen García-Ruiz
- Cell Death and Proliferation, Institute of Biomedical Research of Barcelona (IIBB), CSIC, Barcelona, Spain.,Liver Unit, Hospital Clinic I Provincial de Barcelona, IDIBAPS and CIBERehd, Barcelona, Spain.,Research Center for ALPD, Keck School of Medicine, Univerisity of Southern California, Los Angeles, CA, USA
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100
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Lee GH, Oh KJ, Kim HR, Han HS, Lee HY, Park KG, Nam KH, Koo SH, Chae HJ. Effect of BI-1 on insulin resistance through regulation of CYP2E1. Sci Rep 2016; 6:32229. [PMID: 27576594 PMCID: PMC5006057 DOI: 10.1038/srep32229] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2015] [Accepted: 08/04/2016] [Indexed: 12/21/2022] Open
Abstract
Diet-induced obesity is a major contributing factor to the progression of hepatic insulin resistance. Increased free fatty acids in liver enhances endoplasmic reticulum (ER) stress and production of reactive oxygen species (ROS), both are directly responsible for dysregulation of hepatic insulin signaling. BI-1, a recently studied ER stress regulator, was examined to investigate its association with ER stress and ROS in insulin resistance models. To induce obesity and insulin resistance, BI-1 wild type and BI-1 knock-out mice were fed a high-fat diet for 8 weeks. The BI-1 knock-out mice had hyperglycemia, was associated with impaired glucose and insulin tolerance under high-fat diet conditions. Increased activity of NADPH-dependent CYP reductase-associated cytochrome p450 2E1 (CYP2E1) and exacerbation of ER stress in the livers of BI-1 knock-out mice was also observed. Conversely, stable expression of BI-1 in HepG2 hepatocytes was shown to reduce palmitate-induced ER stress and CYP2E1-dependent ROS production, resulting in the preservation of intact insulin signaling. Stable expression of CYP2E1 led to increased ROS production and dysregulation of insulin signaling in hepatic cells, mimicking palmitate-mediated hepatic insulin resistance. We propose that BI-1 protects against obesity-induced hepatic insulin resistance by regulating CYP2E1 activity and ROS production.
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Affiliation(s)
- Geum-Hwa Lee
- Department of Pharmacology and New Drug Development Institute, Medical School, Chonbuk National University, Jeonju, 561-181, Republic of Korea
| | - Kyoung-Jin Oh
- Division of Life Sciences, Korea University, 145 Anam-Ro, Seongbuk-Gu, Seoul, 136-713, Republic of Korea.,Metabolic Regulation Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon, 305-806, Republic of Korea
| | - Hyung-Ryong Kim
- Department of Dental Pharmacology and Wonkwang Dental Research Institute, School of Dentistry, Wonkwang University, Iksan, 570-749, Republic of Korea
| | - Hye-Sook Han
- Division of Life Sciences, Korea University, 145 Anam-Ro, Seongbuk-Gu, Seoul, 136-713, Republic of Korea
| | - Hwa-Young Lee
- Department of Pharmacology and New Drug Development Institute, Medical School, Chonbuk National University, Jeonju, 561-181, Republic of Korea
| | - Keun-Gyu Park
- Department of Internal Medicine, Kyungpook National University School of Medicine, Daegu, 700-721, Republic of Korea
| | - Ki-Hoan Nam
- Laboratory Animal Resource Center, KRIBB, Ochang-eup, 363-883, Republic of Korea
| | - Seung-Hoi Koo
- Division of Life Sciences, Korea University, 145 Anam-Ro, Seongbuk-Gu, Seoul, 136-713, Republic of Korea
| | - Han-Jung Chae
- Department of Pharmacology and New Drug Development Institute, Medical School, Chonbuk National University, Jeonju, 561-181, Republic of Korea
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