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Sun X, Yu Q, Qi Y, Kang B, Zhao X, Liu L, Wang P, Cong M, Liu T. Peridroplet mitochondria are associated with the severity of MASLD and the prevention of MASLD by diethyldithiocarbamate. J Lipid Res 2024; 65:100590. [PMID: 38981572 PMCID: PMC11381863 DOI: 10.1016/j.jlr.2024.100590] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2023] [Revised: 06/24/2024] [Accepted: 06/26/2024] [Indexed: 07/11/2024] Open
Abstract
Mitochondria can contact lipid droplets (LDs) to form peridroplet mitochondria (PDM) which trap fatty acids in LDs by providing ATP for triglyceride synthesis and prevent lipotoxicity. However, the role of PDM in metabolic dysfunction associated steatotic liver disease (MASLD) is not clear. Here, the features of PDM in dietary MASLD models with different severity in mice were explored. Electron microscope photographs show that LDs and mitochondria rarely come into contact with each other in normal liver. In mice fed with high-fat diet, PDM can be observed in the liver as early as the beginning of steatosis in hepatocytes. For the first time, we show that PDM in mouse liver varies with the severity of MASLD. PDM and cytosolic mitochondria were isolated from the liver tissue of MASLD and analyzed by quantitative proteomics. Compared with cytosolic mitochondria, PDM have enhanced mitochondrial respiration and ATP synthesis. Diethyldithiocarbamate (DDC) alleviates choline-deficient, L-amino acid-defined diet-induced MASLD, while increases PDM in the liver. Similarly, DDC promotes the contact of mitochondria-LDs in steatotic C3A cells in vitro. Meanwhile, DDC promotes triglyceride synthesis and improves mitochondrial dysfunction in MASLD. In addition, DDC upregulates perilipin 5 both in vivo and in vitro, which is considered as a key regulator in PDM formation. Knockout of perilipin 5 inhibits the contact of mitochondria-LDs induced by DDC in C3A cells. These results demonstrate that PDM might be associated with the progression of MASLD and the prevention of MASLD by DDC.
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Affiliation(s)
- Xiangyun Sun
- Liver Research Center, Beijing Friendship Hospital, Capital Medical University, Beijing, China; Department of Hepatology, State Key Lab of Digestive Health, Beijing, China
| | - Qinghong Yu
- Liver Research Center, Beijing Friendship Hospital, Capital Medical University, Beijing, China; Department of Hepatology, State Key Lab of Digestive Health, Beijing, China
| | - Yifei Qi
- Liver Research Center, Beijing Friendship Hospital, Capital Medical University, Beijing, China; Department of Hepatology, State Key Lab of Digestive Health, Beijing, China
| | - Bilian Kang
- Liver Research Center, Beijing Friendship Hospital, Capital Medical University, Beijing, China; Department of Hepatology, State Key Lab of Digestive Health, Beijing, China
| | - Xinyan Zhao
- Liver Research Center, Beijing Friendship Hospital, Capital Medical University, Beijing, China; Department of Hepatology, State Key Lab of Digestive Health, Beijing, China; Department of Hepatology, National Clinical Research Center for Digestive Diseases, Beijing, China; Beijing Key Laboratory of Translational Medicine in Liver Cirrhosis, Beijing, China
| | - Lin Liu
- Liver Research Center, Beijing Friendship Hospital, Capital Medical University, Beijing, China; Department of Hepatology, State Key Lab of Digestive Health, Beijing, China; Department of Hepatology, National Clinical Research Center for Digestive Diseases, Beijing, China; Beijing Key Laboratory of Translational Medicine in Liver Cirrhosis, Beijing, China
| | - Ping Wang
- Liver Research Center, Beijing Friendship Hospital, Capital Medical University, Beijing, China; Department of Hepatology, State Key Lab of Digestive Health, Beijing, China; Department of Hepatology, National Clinical Research Center for Digestive Diseases, Beijing, China; Beijing Key Laboratory of Translational Medicine in Liver Cirrhosis, Beijing, China
| | - Min Cong
- Liver Research Center, Beijing Friendship Hospital, Capital Medical University, Beijing, China; Department of Hepatology, State Key Lab of Digestive Health, Beijing, China; Department of Hepatology, National Clinical Research Center for Digestive Diseases, Beijing, China; Beijing Key Laboratory of Translational Medicine in Liver Cirrhosis, Beijing, China
| | - Tianhui Liu
- Liver Research Center, Beijing Friendship Hospital, Capital Medical University, Beijing, China; Department of Hepatology, State Key Lab of Digestive Health, Beijing, China; Department of Hepatology, National Clinical Research Center for Digestive Diseases, Beijing, China; Beijing Key Laboratory of Translational Medicine in Liver Cirrhosis, Beijing, China.
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Bórquez JC, Díaz-Castro F, La Fuente FPD, Espinoza K, Figueroa AM, Martínez-Ruíz I, Hernández V, López-Soldado I, Ventura R, Domingo JC, Bosch M, Fajardo A, Sebastián D, Espinosa A, Pol A, Zorzano A, Cortés V, Hernández-Alvarez MI, Troncoso R. Mitofusin-2 induced by exercise modifies lipid droplet-mitochondria communication, promoting fatty acid oxidation in male mice with NAFLD. Metabolism 2024; 152:155765. [PMID: 38142958 DOI: 10.1016/j.metabol.2023.155765] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/29/2023] [Revised: 12/09/2023] [Accepted: 12/16/2023] [Indexed: 12/26/2023]
Abstract
BACKGROUND AND AIM The excessive accumulation of lipid droplets (LDs) is a defining characteristic of nonalcoholic fatty liver disease (NAFLD). The interaction between LDs and mitochondria is functionally important for lipid metabolism homeostasis. Exercise improves NAFLD, but it is not known if it has an effect on hepatic LD-mitochondria interactions. Here, we investigated the influence of exercise on LD-mitochondria interactions and its significance in the context of NAFLD. APPROACH AND RESULTS Mice were fed high-fat diet (HFD) or HFD-0.1 % methionine and choline-deficient diet (MCD) to emulate simple hepatic steatosis or non-alcoholic steatohepatitis, respectively. In both models, aerobic exercise decreased the size of LDs bound to mitochondria and the number of LD-mitochondria contacts. Analysis showed that the effects of exercise on HOMA-IR and liver triglyceride levels were independent of changes in body weight, and a positive correlation was observed between the number of LD-mitochondria contacts and NAFLD severity and with the lipid droplet size bound to mitochondria. Cellular fractionation studies revealed that ATP-coupled respiration and fatty acid oxidation (FAO) were greater in hepatic peridroplet mitochondria (PDM) from HFD-fed exercised mice than from equivalent sedentary mice. Finally, exercise increased FAO and mitofusin-2 abundance exclusively in PDM through a mechanism involving the curvature of mitochondrial membranes and the abundance of saturated lipids. Accordingly, hepatic mitofusin-2 ablation prevented exercise-induced FAO in PDM. CONCLUSIONS This study demonstrates that aerobic exercise has beneficial effects in murine NAFLD models by lessening the interactions between hepatic LDs and mitochondria, and by decreasing LD size, correlating with a reduced severity of NAFLD. Additionally, aerobic exercise increases FAO in PDM and this process is reliant on Mfn-2 enrichment, which modifies LD-mitochondria communication.
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Affiliation(s)
- Juan Carlos Bórquez
- Laboratorio de Investigación en Nutrición y Actividad Física (LABINAF), Instituto de Nutrición y Tecnología de los Alimentos (INTA), Universidad de Chile, Chile
| | - Francisco Díaz-Castro
- Laboratorio de Investigación en Nutrición y Actividad Física (LABINAF), Instituto de Nutrición y Tecnología de los Alimentos (INTA), Universidad de Chile, Chile
| | - Francisco Pino-de La Fuente
- Laboratorio de Investigación en Nutrición y Actividad Física (LABINAF), Instituto de Nutrición y Tecnología de los Alimentos (INTA), Universidad de Chile, Chile
| | - Karla Espinoza
- Laboratorio de Investigación en Nutrición y Actividad Física (LABINAF), Instituto de Nutrición y Tecnología de los Alimentos (INTA), Universidad de Chile, Chile
| | - Ana María Figueroa
- Department of Nutrition, Diabetes and Metabolism, Pontificia Universidad Católica de Chile, Chile
| | - Inma Martínez-Ruíz
- Departament de Bioquímica i Biomedicina Molecular, Facultat de Biologia, Universitat de Barcelona, Barcelona, Spain; Institut de Biomedicina de la Universitat de Barcelona IBUB, Barcelona, Spain
| | - Vanessa Hernández
- Institute for Research in Biomedicine (IRB Barcelona). The Barcelona Institute of Science and Technology, Barcelona (BIST), Spain
| | - Iliana López-Soldado
- Departament de Bioquímica i Biomedicina Molecular, Facultat de Biologia, Universitat de Barcelona, Barcelona, Spain; Institut de Biomedicina de la Universitat de Barcelona IBUB, Barcelona, Spain
| | - Raúl Ventura
- Departament de Bioquímica i Biomedicina Molecular, Facultat de Biologia, Universitat de Barcelona, Barcelona, Spain; Institut de Biomedicina de la Universitat de Barcelona IBUB, Barcelona, Spain
| | - Joan Carles Domingo
- Departament de Bioquímica i Biomedicina Molecular, Facultat de Biologia, Universitat de Barcelona, Barcelona, Spain
| | - Marta Bosch
- Cell Compartments and Signaling Group, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain
| | - Alba Fajardo
- Cell Compartments and Signaling Group, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain
| | - David Sebastián
- Department of Biochemistry and Physiology, Faculty of Pharmacy and Food Sciences, University of Barcelona, Barcelona, Spain
| | - Alejandra Espinosa
- Escuela de Medicina, Campus San Felipe, Universidad de Valparaíso, Chile; Department of Medical Technology, Faculty of Medicine, University of Chile, Chile
| | - Albert Pol
- Cell Compartments and Signaling Group, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain
| | - Antonio Zorzano
- Departament de Bioquímica i Biomedicina Molecular, Facultat de Biologia, Universitat de Barcelona, Barcelona, Spain; Institute for Research in Biomedicine (IRB Barcelona). The Barcelona Institute of Science and Technology, Barcelona (BIST), Spain; CIBER de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), Spain
| | - Víctor Cortés
- Department of Nutrition, Diabetes and Metabolism, Pontificia Universidad Católica de Chile, Chile.
| | - María Isabel Hernández-Alvarez
- Departament de Bioquímica i Biomedicina Molecular, Facultat de Biologia, Universitat de Barcelona, Barcelona, Spain; Institut de Biomedicina de la Universitat de Barcelona IBUB, Barcelona, Spain; CIBER de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), Spain.
| | - Rodrigo Troncoso
- Laboratorio de Investigación en Nutrición y Actividad Física (LABINAF), Instituto de Nutrición y Tecnología de los Alimentos (INTA), Universidad de Chile, Chile; Advanced Center for Chronic Diseases (ACCDiS), Universidad de Chile, Chile; Obesity-induced Accelerated Aging (ObAGE), Universidad de Chile, Chile.
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Jin S, Li Y, Xia T, Liu Y, Zhang S, Hu H, Chang Q, Yan M. Mechanisms and therapeutic implications of selective autophagy in nonalcoholic fatty liver disease. J Adv Res 2024:S2090-1232(24)00041-9. [PMID: 38295876 DOI: 10.1016/j.jare.2024.01.027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2023] [Revised: 01/24/2024] [Accepted: 01/25/2024] [Indexed: 02/08/2024] Open
Abstract
BACKGROUND Nonalcoholic fatty liver disease (NAFLD) has become the most common chronic liver disease worldwide, whereas there is no approved drug therapy due to its complexity. Studies are emerging to discuss the role of selective autophagy in the pathogenesis of NAFLD, because the specificity among the features of selective autophagy makes it a crucial process in mitigating hepatocyte damage caused by aberrant accumulation of dysfunctional organelles, for which no other pathway can compensate. AIM OF REVIEW This review aims to summarize the types, functions, and dynamics of selective autophagy that are of particular importance in the initiation and progression of NAFLD. And on this basis, the review outlines the therapeutic strategies against NAFLD, in particular the medications and potential natural products that can modulate selective autophagy in the pathogenesis of this disease. KEY SCIENTIFIC CONCEPTS OF REVIEW The critical roles of lipophagy and mitophagy in the pathogenesis of NAFLD are well established, while reticulophagy and pexophagy are still being identified in this disease due to the insufficient understanding of their molecular details. As gradual blockage of autophagic flux reveals the complexity of NAFLD, studies unraveling the underlying mechanisms have made it possible to successfully treat NAFLD with multiple pharmacological compounds that target associated pathways. Overall, it is convinced that the continued research into selective autophagy occurring in NAFLD will further enhance the understanding of the pathogenesis and uncover novel therapeutic targets.
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Affiliation(s)
- Suwei Jin
- Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences and Peking Union Medical College, China
| | - Yujia Li
- Department of Medicine II, University Medical Center Mannheim, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | - Tianji Xia
- Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences and Peking Union Medical College, China
| | - Yongguang Liu
- Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences and Peking Union Medical College, China
| | - Shanshan Zhang
- Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences and Peking Union Medical College, China
| | - Hongbo Hu
- College of Food Science and Nutritional Engineering, China Agricultural University, China.
| | - Qi Chang
- Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences and Peking Union Medical College, China.
| | - Mingzhu Yan
- Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences and Peking Union Medical College, China.
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Minami Y, Hoshino A, Higuchi Y, Hamaguchi M, Kaneko Y, Kirita Y, Taminishi S, Nishiji T, Taruno A, Fukui M, Arany Z, Matoba S. Liver lipophagy ameliorates nonalcoholic steatohepatitis through extracellular lipid secretion. Nat Commun 2023; 14:4084. [PMID: 37443159 PMCID: PMC10344867 DOI: 10.1038/s41467-023-39404-6] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2021] [Accepted: 06/12/2023] [Indexed: 07/15/2023] Open
Abstract
Nonalcoholic steatohepatitis (NASH) is a progressive disorder with aberrant lipid accumulation and subsequent inflammatory and profibrotic response. Therapeutic efforts at lipid reduction via increasing cytoplasmic lipolysis unfortunately worsens hepatitis due to toxicity of liberated fatty acid. An alternative approach could be lipid reduction through autophagic disposal, i.e., lipophagy. We engineered a synthetic adaptor protein to induce lipophagy, combining a lipid droplet-targeting signal with optimized LC3-interacting domain. Activating hepatocyte lipophagy in vivo strongly mitigated both steatosis and hepatitis in a diet-induced mouse NASH model. Mechanistically, activated lipophagy promoted the excretion of lipid from hepatocytes, thereby suppressing harmful intracellular accumulation of nonesterified fatty acid. A high-content compound screen identified alpelisib and digoxin, clinically-approved compounds, as effective activators of lipophagy. Administration of alpelisib or digoxin in vivo strongly inhibited the transition to steatohepatitis. These data thus identify lipophagy as a promising therapeutic approach to prevent NASH progression.
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Affiliation(s)
- Yoshito Minami
- Department of Cardiovascular Medicine, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, 602-8566, Japan
| | - Atsushi Hoshino
- Department of Cardiovascular Medicine, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, 602-8566, Japan.
| | - Yusuke Higuchi
- Department of Cardiovascular Medicine, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, 602-8566, Japan
| | - Masahide Hamaguchi
- Department of Endocrinology and Metabolism, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, 602-8566, Japan
| | - Yusaku Kaneko
- Department of Cardiovascular Medicine, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, 602-8566, Japan
| | - Yuhei Kirita
- Department of Nephrology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, 602-8566, Japan
| | - Shunta Taminishi
- Department of Cardiovascular Medicine, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, 602-8566, Japan
| | - Toshiyuki Nishiji
- Department of Cardiovascular Medicine, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, 602-8566, Japan
| | - Akiyuki Taruno
- Department of Molecular Cell Physiology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, 602-8566, Japan
- Japan Science and Technology Agency, PRESTO, Kawaguchi, Saitama, 332-0012, Japan
- Japan Science and Technology Agency, CREST, Kawaguchi, Saitama, 332-0012, Japan
| | - Michiaki Fukui
- Department of Endocrinology and Metabolism, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, 602-8566, Japan
| | - Zoltan Arany
- Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA.
| | - Satoaki Matoba
- Department of Cardiovascular Medicine, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, 602-8566, Japan
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Liang WM, Xiao J, Ren FF, Chen ZS, Li CR, Bai ZM, Rukšenas O. Acute effect of breathing exercises on muscle tension and executive function under psychological stress. Front Psychol 2023; 14:1155134. [PMID: 37303921 PMCID: PMC10249663 DOI: 10.3389/fpsyg.2023.1155134] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Accepted: 04/06/2023] [Indexed: 06/13/2023] Open
Abstract
Introduction Intensive and long-lasting office work is a common cause of muscular and mental disorders due to workplace stressors. Mindful and slow breathing exercises decrease psychological stress and improve mental health, whereas fast breathing increases neuronal excitability. This study aimed to explore the influence of 5 min of mindful breathing (MINDFUL), slow breathing (SLOW), fast breathing (FAST), and listening to music (MUSIC) on muscle tension and executive function during an intensive psychological task. Methods Forty-eight participants (24 men and 24 women) were enrolled. Muscle tension was recorded using surface electromyography, and executive function was assessed using the Stroop Color and Word Test (Stroop Test). The respiration rate (RR), oxygen saturation (SpO2), end-tidal carbon dioxide (EtCO2), and the subjects' preferred method were also recorded. During the experiment, participants performed a one-time baseline test (watching a neutral video for 5 min) and then completed 5 min of MUSIC, MINDFUL, SLOW, and FAST in a random sequence. The Stroop Test was performed after each intervention, including the baseline test, and was followed by a 5 min rest before performing the next intervention. Results None of the methods significantly influenced muscular activity and performance of the Stroop Test in both men and women, based on the average 5 min values. However, at the fifth minute, men's accuracy rate in the Stroop Test was significantly higher after SLOW than after MUSIC and FAST, and the reaction time after the SLOW was the shortest. SpO2 was significantly higher during SLOW than during MUSIC, and RR was relatively lower after SLOW than after MUSIC. Most men preferred SLOW, and most women preferred MUSIC, whereas FAST was the most unfavorable method for both men and women. Conclusion Brief breathing exercises did not substantially affect muscle tension under psychological stress. SLOW demonstrated greater potential for sustaining executive function in men, possibly via its superior respiration efficiency on SpO2 and inhibition of RR.
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Affiliation(s)
- Wen-Ming Liang
- Department of Neurobiology and Biophysics, Life Sciences Center, Vilnius University, Vilnius, Lithuania
- Department of Physiotherapy and Rehabilitation, Xiyuan Hospital, Chinese Academy of Chinese Medical Sciences, Beijing, China
| | - Jing Xiao
- Department of Physiotherapy and Rehabilitation, Xiyuan Hospital, Chinese Academy of Chinese Medical Sciences, Beijing, China
| | - Fei-Fei Ren
- Department of Physical Education, Beijing Language and Culture University, Beijing, China
| | - Zi-Shuai Chen
- Department of Traditional Chinese Exercises, College of Physical Education, Minzu University of China, Beijing, China
| | - Chun-Ri Li
- Department of Acupuncture, College of Acupuncture and Moxibustion, Liaoning University of Traditional Chinese Medicine, Shenyang, China
- Faculty of Health, Slovak Medical University, Banská Bystrica, Slovakia
| | - Zhen-Min Bai
- Department of Sports Rehabilitation, School of Sports Medicine and Rehabilitation, Beijing Sport University, Beijing, China
| | - Osvaldas Rukšenas
- Department of Neurobiology and Biophysics, Life Sciences Center, Vilnius University, Vilnius, Lithuania
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Amorim R, Magalhães CC, Borges F, Oliveira PJ, Teixeira J. From Non-Alcoholic Fatty Liver to Hepatocellular Carcinoma: A Story of (Mal)Adapted Mitochondria. BIOLOGY 2023; 12:biology12040595. [PMID: 37106795 PMCID: PMC10135755 DOI: 10.3390/biology12040595] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2023] [Revised: 03/30/2023] [Accepted: 04/11/2023] [Indexed: 04/29/2023]
Abstract
Non-alcoholic fatty liver disease (NAFLD) is a global pandemic affecting 25% of the world's population and is a serious health and economic concern worldwide. NAFLD is mainly the result of unhealthy dietary habits combined with sedentary lifestyle, although some genetic contributions to NAFLD have been documented. NAFLD is characterized by the excessive accumulation of triglycerides (TGs) in hepatocytes and encompasses a spectrum of chronic liver abnormalities, ranging from simple steatosis (NAFL) to steatohepatitis (NASH), significant liver fibrosis, cirrhosis, and hepatocellular carcinoma. Although the molecular mechanisms that cause the progression of steatosis to severe liver damage are not fully understood, metabolic-dysfunction-associated fatty liver disease is strong evidence that mitochondrial dysfunction plays a significant role in the development and progression of NAFLD. Mitochondria are highly dynamic organelles that undergo functional and structural adaptations to meet the metabolic requirements of the cell. Alterations in nutrient availability or cellular energy needs can modify mitochondria formation through biogenesis or the opposite processes of fission and fusion and fragmentation. In NAFL, simple steatosis can be seen as an adaptive response to storing lipotoxic free fatty acids (FFAs) as inert TGs due to chronic perturbation in lipid metabolism and lipotoxic insults. However, when liver hepatocytes' adaptive mechanisms are overburdened, lipotoxicity occurs, contributing to reactive oxygen species (ROS) formation, mitochondrial dysfunction, and endoplasmic reticulum (ER) stress. Impaired mitochondrial fatty acid oxidation, reduction in mitochondrial quality, and disrupted mitochondrial function are associated with a decrease in the energy levels and impaired redox balance and negatively affect mitochondria hepatocyte tolerance towards damaging hits. However, the sequence of events underlying mitochondrial failure from steatosis to hepatocarcinoma is still yet to be fully clarified. This review provides an overview of our understanding of mitochondrial adaptation in initial NAFLD stages and highlights how hepatic mitochondrial dysfunction and heterogeneity contribute to disease pathophysiology progression, from steatosis to hepatocellular carcinoma. Improving our understanding of different aspects of hepatocytes' mitochondrial physiology in the context of disease development and progression is crucial to improving diagnosis, management, and therapy of NAFLD/NASH.
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Affiliation(s)
- Ricardo Amorim
- CNC-Center for Neuroscience and Cell Biology, CIBB-Centre for Innovative Biomedicine and Biotechnology, University of Coimbra, 3004-504 Coimbra, Portugal
- CIQUP-IMS/Department of Chemistry and Biochemistry, Faculty of Sciences, University of Porto, 4169-007 Porto, Portugal
| | - Carina C Magalhães
- CNC-Center for Neuroscience and Cell Biology, CIBB-Centre for Innovative Biomedicine and Biotechnology, University of Coimbra, 3004-504 Coimbra, Portugal
| | - Fernanda Borges
- CIQUP-IMS/Department of Chemistry and Biochemistry, Faculty of Sciences, University of Porto, 4169-007 Porto, Portugal
| | - Paulo J Oliveira
- CNC-Center for Neuroscience and Cell Biology, CIBB-Centre for Innovative Biomedicine and Biotechnology, University of Coimbra, 3004-504 Coimbra, Portugal
| | - José Teixeira
- CNC-Center for Neuroscience and Cell Biology, CIBB-Centre for Innovative Biomedicine and Biotechnology, University of Coimbra, 3004-504 Coimbra, Portugal
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Zhang E. Hepatic PLIN5 Deficiency Impairs Lipogenesis through Mitochondrial Dysfunction. Int J Mol Sci 2022; 23:15598. [PMID: 36555245 PMCID: PMC9779494 DOI: 10.3390/ijms232415598] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2022] [Revised: 12/01/2022] [Accepted: 12/07/2022] [Indexed: 12/14/2022] Open
Abstract
Regulation of lipid droplets (LDs) metabolism is the core of controlling intracellular fatty acids (FAs) fluxes, and perilipin 5 (PLIN5) plays a key role in this process. Our previous studies have found that hepatic PLIN5 deficiency reduces LDs accumulation, but the trafficking of FAs produced from this pathway and the interaction between mitochondria and LDs in this process are largely unknown. Here, we found that the deficiency of PLIN5 decreases LDs accumulation by increasing FAs efflux. In addition, the decreased lipogenesis of PLIN5-deficient hepatocytes is accompanied by mitochondrial dysfunction, suggesting that PLIN5 plays an important role in mediating the interaction between LDs and mitochondria. Importantly, PLIN5 ablation negates oxidative capacity differences of peri-droplet and cytosolic mitochondria. In summary, these data indicate that PLIN5 plays a vital role in maintaining mitochondrial-mediated lipogenesis, which provides an important new perspective on the regulation of liver lipid storage and the relationship between PLIN5 and mitochondria.
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Affiliation(s)
- Enxiang Zhang
- Key Laboratory of Growth Regulation and Transformation Research of Zhejiang Province, School of Life Sciences, Westlake Institute for Advanced Study, Westlake University, Hangzhou 310024, China;
- Department of Cell Biology, Duke University Medical Center, Durham, NC 27710, USA
- Duke Regeneration Center, Duke University Medical Center, Durham, NC 27710, USA
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Steffen J, Ngo J, Wang SP, Williams K, Kramer HF, Ho G, Rodriguez C, Yekkala K, Amuzie C, Bialecki R, Norquay L, Nawrocki AR, Erion M, Pocai A, Shirihai OS, Liesa M. The mitochondrial fission protein Drp1 in liver is required to mitigate NASH and prevents the activation of the mitochondrial ISR. Mol Metab 2022; 64:101566. [PMID: 35940556 PMCID: PMC9420962 DOI: 10.1016/j.molmet.2022.101566] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/25/2022] [Revised: 07/14/2022] [Accepted: 07/29/2022] [Indexed: 11/22/2022] Open
Abstract
OBJECTIVE The mitochondrial fission protein Drp1 was proposed to promote NAFLD, as inhibition of hepatocyte Drp1 early in life prevents liver steatosis induced by high-fat diet in mice. However, whether Drp1-knockdown in older mice can reverse established NASH is unknown. METHODS N-acetylgalactosamine-siRNA conjugates, an FDA approved method to deliver siRNA selectively to hepatocytes, were used to knockdown hepatocyte-Drp1 in mice (NAG-Drp1si). NASH was induced in C57BL/6NTac mice by Gubra-Amylin-NASH diet (D09100310, 40% fat, 22% fructose and 2% cholesterol) and treatment with NAG-Drp1si was started at week 24 of diet. Circulating transaminases, liver histology, gene expression of fibrosis and inflammation markers, and hydroxyproline synthesis determined NASH severity. Liver NEFA and triglycerides were quantified by GC/MS. Mitochondrial function was determined by respirometry. Western blots of Oma1, Opa1, p-eIf2α, as well as transcriptional analyses of Atf4-regulated genes determined ISR engagement. RESULTS NAG-Drp1si treatment decreased body weight and induced liver inflammation in adult healthy mice. Increased hepatic Gdf15 production was the major contributor to body-weight loss caused by NAG-Drp1si treatment, as Gdf15 receptor deletion (Gfral KO) prevented the decrease in food intake and mitigated weight loss. NAG-Drp1si activated the Atf4-controlled integrated stress response (ISR) to increase hepatic Gdf15 expression. NAG-Drp1si in healthy mice caused ER stress and activated the mitochondrial protease Oma1, which are the ER and mitochondrial triggers that activate the Atf4-controlled ISR. Remarkably, induction of NASH was not sufficient to activate Oma1 in liver. However, NAG-Drp1si treatment was sufficient to activate Oma1 in adult mice with NASH, as well as exacerbating NASH-induced ER stress. Consequently, NAG-Drp1si treatment in mice with NASH led to higher ISR activation, exacerbated inflammation, fibrosis and necrosis. CONCLUSION Drp1 mitigates NASH by decreasing ER stress, preventing Oma1 activation and ISR exacerbation. The elevation in Gdf15 actions induced by NAG-Drp1si might represent an adaptive response decreasing the nutrient load to liver when mitochondria are misfunctional. Our study argues against blocking Drp1 in hepatocytes to combat NASH.
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Affiliation(s)
- Janos Steffen
- Cardiovascular and Metabolic Disease Research, Janssen Research & Development, LLC, 1400 McKean Road, Spring House, PA 19477-0776, USA
| | - Jennifer Ngo
- Department of Chemistry and Biochemistry, UCLA. 607 Charles E. Young Dr., Los Angeles, CA 90095, USA; Department of Medicine, Division of Endocrinology, David Geffen School of Medicine at UCLA. 650 Charles E. Young Dr., Los Angeles, CA 90095, USA
| | - Sheng-Ping Wang
- Cardiovascular and Metabolic Disease Research, Janssen Research & Development, LLC, 1400 McKean Road, Spring House, PA 19477-0776, USA
| | - Kevin Williams
- Department of Chemistry and Biochemistry, UCLA. 607 Charles E. Young Dr., Los Angeles, CA 90095, USA
| | - Henning F Kramer
- Cardiovascular and Metabolic Disease Research, Janssen Research & Development, LLC, 1400 McKean Road, Spring House, PA 19477-0776, USA
| | - George Ho
- Cardiovascular and Metabolic Disease Research, Janssen Research & Development, LLC, 1400 McKean Road, Spring House, PA 19477-0776, USA
| | - Carlos Rodriguez
- Cardiovascular and Metabolic Disease Research, Janssen Research & Development, LLC, 1400 McKean Road, Spring House, PA 19477-0776, USA
| | - Krishna Yekkala
- Preclinical Safety and Translational Sciences, Janssen Research & Development, LLC, 1400 McKean Road, Spring House, PA 19477-0776, USA
| | - Chidozie Amuzie
- Preclinical Safety and Translational Sciences, Janssen Research & Development, LLC, 1400 McKean Road, Spring House, PA 19477-0776, USA
| | - Russell Bialecki
- Preclinical Safety and Translational Sciences, Janssen Research & Development, LLC, 1400 McKean Road, Spring House, PA 19477-0776, USA
| | - Lisa Norquay
- Business Development, Janssen Research & Development, LLC, 1400 McKean Road, Spring House, PA 19477-0776, USA
| | - Andrea R Nawrocki
- Cardiovascular and Metabolic Disease Research, Janssen Research & Development, LLC, 1400 McKean Road, Spring House, PA 19477-0776, USA
| | - Mark Erion
- Cardiovascular and Metabolic Disease Research, Janssen Research & Development, LLC, 1400 McKean Road, Spring House, PA 19477-0776, USA
| | - Alessandro Pocai
- Cardiovascular and Metabolic Disease Research, Janssen Research & Development, LLC, 1400 McKean Road, Spring House, PA 19477-0776, USA.
| | - Orian S Shirihai
- Department of Medicine, Division of Endocrinology, David Geffen School of Medicine at UCLA. 650 Charles E. Young Dr., Los Angeles, CA 90095, USA; Department of Molecular and Medical Pharmacology, David Geffen School of Medicine at UCLA. 650 Charles E. Young Dr., Los Angeles, CA 90095, USA.
| | - Marc Liesa
- Department of Medicine, Division of Endocrinology, David Geffen School of Medicine at UCLA. 650 Charles E. Young Dr., Los Angeles, CA 90095, USA; Department of Molecular and Medical Pharmacology, David Geffen School of Medicine at UCLA. 650 Charles E. Young Dr., Los Angeles, CA 90095, USA; Molecular Biology Institute at UCLA, 611 Charles E. Young Drive East, Los Angeles, CA 90095-1570, USA; Institut de Biologia Molecular de Barcelona, IBMB, CSIC, Baldiri Reixac 4-8, Barcelona, Catalonia, 08028, Spain.
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9
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Plin5, a New Target in Diabetic Cardiomyopathy. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2022; 2022:2122856. [PMID: 35509833 PMCID: PMC9060988 DOI: 10.1155/2022/2122856] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/16/2022] [Revised: 03/14/2022] [Accepted: 04/06/2022] [Indexed: 02/07/2023]
Abstract
Abnormal lipid accumulation is commonly observed in diabetic cardiomyopathy (DC), which can create a lipotoxic microenvironment and damage cardiomyocytes. Lipid toxicity is an important pathogenic factor due to abnormal lipid accumulation in DC. As a lipid droplet (LD) decomposition barrier, Plin5 can protect LDs from lipase decomposition and regulate lipid metabolism, which is involved in the occurrence and development of cardiovascular diseases. In recent years, studies have shown that Plin5 expression is involved in the pathogenesis of DC lipid toxicity, such as oxidative stress, mitochondrial dysfunction, endoplasmic reticulum (ER) stress, and insulin resistance (IR) and has become a key target of DC research. Therefore, understanding the relationship between Plin5 and DC progression as well as the mechanism of this process is crucial for developing new therapeutic approaches and exploring new therapeutic targets. This review is aimed at exploring the latest findings and roles of Plin5 in lipid metabolism and DC-related pathogenesis, to explore possible clinical intervention approaches.
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10
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Pino-de la Fuente F, Bórquez JC, Díaz-Castro F, Espinosa A, Chiong M, Troncoso R. Exercise regulation of hepatic lipid droplet metabolism. Life Sci 2022; 298:120522. [PMID: 35367244 DOI: 10.1016/j.lfs.2022.120522] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2022] [Revised: 03/16/2022] [Accepted: 03/27/2022] [Indexed: 01/02/2023]
Abstract
Lipid droplets (LD) are not just lipid stores. They are now recognized as highly dynamic organelles, having a life cycle that includes biogenesis, growth, steady-state, transport, and catabolism. Importantly, LD exhibit different features in terms of size, number, lipid composition, proteins, and interaction with other organelles, and all these features exert an impact on cellular homeostasis. The imbalance of LD function causes non-alcoholic fatty liver disease (NAFLD). Studies show that exercise attenuates NAFLD by decreasing LD content; however, reports show metabolic benefits without changes in LD amount (intrahepatic triglyceride levels) in NAFLD. Due to the multiple effects of exercise in LD features, we think that these metabolic benefits occur through changes in LD features in NAFLD, rather than only the reduction in content. Exercise increases energy mobilization and utilization from storages such as LD, and is one of the non-pharmacological treatments against NAFLD. Therefore, exercise modification of LD could be a target for NAFLD treatment. Here, we review the most up-to-date literature on this topic, and focus on recent findings showing that LD features could play an important role in the severity of NAFLD.
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Affiliation(s)
- Francisco Pino-de la Fuente
- Laboratorio de Investigación en Nutrición y Actividad Física (LABINAF), Instituto de Nutrición y Tecnología de los Alimentos (INTA), Universidad de Chile, Santiago, Chile; Departamento de Tecnología Médica, Facultad de Medicina, Universidad de Chile, Chile; Advanced Center for Chronic Diseases (ACCDiS), Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago, Chile
| | - Juan Carlos Bórquez
- Laboratorio de Investigación en Nutrición y Actividad Física (LABINAF), Instituto de Nutrición y Tecnología de los Alimentos (INTA), Universidad de Chile, Santiago, Chile
| | - Francisco Díaz-Castro
- Laboratorio de Investigación en Nutrición y Actividad Física (LABINAF), Instituto de Nutrición y Tecnología de los Alimentos (INTA), Universidad de Chile, Santiago, Chile
| | - Alejandra Espinosa
- Departamento de Tecnología Médica, Facultad de Medicina, Universidad de Chile, Chile
| | - Mario Chiong
- Advanced Center for Chronic Diseases (ACCDiS), Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago, Chile
| | - Rodrigo Troncoso
- Laboratorio de Investigación en Nutrición y Actividad Física (LABINAF), Instituto de Nutrición y Tecnología de los Alimentos (INTA), Universidad de Chile, Santiago, Chile; Advanced Center for Chronic Diseases (ACCDiS), Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago, Chile.
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11
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Abstract
Lipid droplets (LDs) are ubiquitous organelles that store and supply lipids for energy metabolism, membrane synthesis and production of lipid-derived signaling molecules. While compositional differences in the phospholipid monolayer or neutral lipid core of LDs impact their metabolism and function, the proteome of LDs has emerged as a major influencer in all aspects of LD biology. The perilipins (PLINs) are the most studied and abundant proteins residing on the LD surface. This Cell Science at a Glance and the accompanying poster summarize our current knowledge of the common and unique features of the mammalian PLIN family of proteins, the mechanisms through which they affect cell metabolism and signaling, and their links to disease.
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Affiliation(s)
- Charles P. Najt
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA
| | - Mahima Devarajan
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA
| | - Douglas G. Mashek
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA
- Department of Medicine, Division of Diabetes, Endocrinology and Metabolism, University of Minnesota, Minneapolis, MN 55455, USA
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12
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ŞAHİN İE, HACIOĞLU C, DAVRAN F, ALPAY M. Perilipin-5 as a potential new biomarker in patients with liver disease and impaired De Ritis ratio. CUKUROVA MEDICAL JOURNAL 2021. [DOI: 10.17826/cumj.975899] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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13
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Eynaudi A, Díaz-Castro F, Bórquez JC, Bravo-Sagua R, Parra V, Troncoso R. Differential Effects of Oleic and Palmitic Acids on Lipid Droplet-Mitochondria Interaction in the Hepatic Cell Line HepG2. Front Nutr 2021; 8:775382. [PMID: 34869541 PMCID: PMC8632770 DOI: 10.3389/fnut.2021.775382] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2021] [Accepted: 10/15/2021] [Indexed: 12/18/2022] Open
Abstract
Fatty acid overload, either of the saturated palmitic acid (PA) or the unsaturated oleic acid (OA), causes triglyceride accumulation into specialized organelles termed lipid droplets (LD). However, only PA overload leads to liver damage mediated by mitochondrial dysfunction. Whether these divergent outcomes stem from differential effects of PA and OA on LD and mitochondria joint dynamics remains to be uncovered. Here, we contrast how both fatty acids impact the morphology and interaction between both organelles and mitochondrial bioenergetics in HepG2 cells. Using confocal microscopy, we showed that short-term (2–24 h) OA overload promotes more and bigger LD accumulation than PA. Oxygen polarography indicated that both treatments stimulated mitochondrial respiration; however, OA favored an overall build-up of the mitochondrial potential, and PA evoked mitochondrial fragmentation, concomitant with an ATP-oriented metabolism. Even though PA-induced a lesser increase in LD-mitochondria proximity than OA, those LD associated with highly active mitochondria suggest that they interact mainly to fuel fatty acid oxidation and ATP synthesis (that is, metabolically “active” LD). On the contrary, OA overload seemingly stimulated LD-mitochondria interaction mainly for LD growth (thus metabolically “passive” LDs). In sum, these differences point out that OA readily accumulates in LD, likely reducing their toxicity, while PA preferably stimulates mitochondrial oxidative metabolism, which may contribute to liver damage progression.
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Affiliation(s)
- Andrea Eynaudi
- Laboratorio de Investigación en Nutrición y Actividad Física (LABINAF), Instituto de Nutrición y Tecnología de los Alimentos (INTA), Universidad de Chile, Santiago, Chile
| | - Francisco Díaz-Castro
- Laboratorio de Investigación en Nutrición y Actividad Física (LABINAF), Instituto de Nutrición y Tecnología de los Alimentos (INTA), Universidad de Chile, Santiago, Chile
| | - Juan Carlos Bórquez
- Laboratorio de Investigación en Nutrición y Actividad Física (LABINAF), Instituto de Nutrición y Tecnología de los Alimentos (INTA), Universidad de Chile, Santiago, Chile
| | - Roberto Bravo-Sagua
- Laboratorio de Obesidad y Metabolismo Energético (OMEGA), Instituto de Nutrición y Tecnología de los Alimentos (INTA), Universidad de Chile, Santiago, Chile.,Advanced Center for Chronic Diseases (ACCDiS), Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago, Chile.,Red de Investigación en Envejecimiento Saludable, Consorcio de Universidades del Estado de Chile, Santiago, Chile
| | - Valentina Parra
- Advanced Center for Chronic Diseases (ACCDiS), Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago, Chile.,Red Para el Estudio de Enfermedades Cardiopulmonares de Alta Letalidad (REECPAL), Universidad de Chile, Santiago, Chile
| | - Rodrigo Troncoso
- Laboratorio de Investigación en Nutrición y Actividad Física (LABINAF), Instituto de Nutrición y Tecnología de los Alimentos (INTA), Universidad de Chile, Santiago, Chile.,Advanced Center for Chronic Diseases (ACCDiS), Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago, Chile
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14
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Ma Y, Yin X, Qin Z, Ke X, Mi Y, Zheng P, Tang Y. Role of Plin5 Deficiency in Progression of Non-Alcoholic Fatty Liver Disease Induced by a High-Fat Diet in Mice. J Comp Pathol 2021; 189:88-97. [PMID: 34886991 DOI: 10.1016/j.jcpa.2021.10.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2021] [Revised: 05/14/2021] [Accepted: 10/04/2021] [Indexed: 11/23/2022]
Abstract
Characterized by steatosis, inflammation and fibrosis, non-alcoholic fatty liver disease (NAFLD) is a metabolic disorder. As a major lipid droplet-binding protein, Plin5 has been reported to have multiple effects on metabolism, but the effect of Plin5 deficiency on NAFLD is unknown. Plin5 knockout mice and wild-type mice were used to investigate the role of Plin5 in the progression of NAFLD by feeding a high-fat diet (HFD) for 20 weeks. Plin5 deficiency improved obesity induced by the HFD and altered glucose tolerance. Histological examination revealed that Plin5 deficiency alleviated hepatic steatosis and fibrosis induced by the HFD. Plin5 deficiency was also associated with a significant change in lipid metabolism-associated molecules. Further studies of these molecules indicated that Plin5 deficiency activated the expression of AMP-activated protein kinase and inhibited the core regulator of lipogenesis, sterol regulatory element binding protein 1 and its downstream lipid synthesis-related genes. These findings suggest that Plin5 deficiency ameliorates NAFLD by regulating lipid metabolism and inhibiting lipogenesis, and may provide a new strategy for the treatment of NAFLD.
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Affiliation(s)
- Yuying Ma
- Academy of Medical Sciences, Zhengzhou, Henan, China; Department of Gastroenterology and Hepatology, Key Laboratory of H. Pylori and Gastrointestinal Microecology of Henan Province, Fifth Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, China
| | - Xuecui Yin
- Academy of Medical Sciences, Zhengzhou, Henan, China; Department of Gastroenterology and Hepatology, Key Laboratory of H. Pylori and Gastrointestinal Microecology of Henan Province, Fifth Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, China
| | - Zhenzhen Qin
- Department of Endocrine Geriatrics, Seventh People's Hospital of Zhengzhou, Zhengzhou, Henan, China
| | - Xiaofei Ke
- Department of Pediatrics, Fifth Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, China
| | - Yang Mi
- Department of Gastroenterology and Hepatology, Key Laboratory of H. Pylori and Gastrointestinal Microecology of Henan Province, Fifth Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, China
| | - Pengyuan Zheng
- Department of Gastroenterology and Hepatology, Key Laboratory of H. Pylori and Gastrointestinal Microecology of Henan Province, Fifth Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, China
| | - Youcai Tang
- Department of Gastroenterology and Hepatology, Key Laboratory of H. Pylori and Gastrointestinal Microecology of Henan Province, Fifth Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, China; Department of Pediatrics, Fifth Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, China; Henan Key Laboratory of Rehabilitation Medicine, Henan Joint International Research Laboratory of Chronic Liver Injury, Fifth Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, China.
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15
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Ngo J, Osto C, Villalobos F, Shirihai OS. Mitochondrial Heterogeneity in Metabolic Diseases. BIOLOGY 2021; 10:biology10090927. [PMID: 34571805 PMCID: PMC8470264 DOI: 10.3390/biology10090927] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/01/2021] [Revised: 09/03/2021] [Accepted: 09/08/2021] [Indexed: 11/16/2022]
Abstract
Simple Summary Often times mitochondria within a single cell are depicted as homogenous entities both morphologically and functionally. In normal and diseased states, mitochondria are heterogeneous and display distinct functional properties. In both cases, mitochondria exhibit differences in morphology, membrane potential, and mitochondrial calcium levels. However, the degree of heterogeneity is different during disease; or rather, heterogeneity at the physiological state stems from physically distinct mitochondrial subpopulations. Overall, mitochondrial heterogeneity is both beneficial and detrimental to the cellular system; protective in enabling cellular adaptation to biological stress or detrimental in inhibiting protective mechanisms. Abstract Mitochondria have distinct architectural features and biochemical functions consistent with cell-specific bioenergetic needs. However, as imaging and isolation techniques advance, heterogeneity amongst mitochondria has been observed to occur within the same cell. Moreover, mitochondrial heterogeneity is associated with functional differences in metabolic signaling, fuel utilization, and triglyceride synthesis. These phenotypic associations suggest that mitochondrial subpopulations and heterogeneity influence the risk of metabolic diseases. This review examines the current literature regarding mitochondrial heterogeneity in the pancreatic beta-cell and renal proximal tubules as they exist in the pathological and physiological states; specifically, pathological states of glucolipotoxicity, progression of type 2 diabetes, and kidney diseases. Emphasis will be placed on the benefits of balancing mitochondrial heterogeneity and how the disruption of balancing heterogeneity leads to impaired tissue function and disease onset.
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Affiliation(s)
- Jennifer Ngo
- Department of Medicine, Division of Endocrinology, David Geffen School of Medicine at UCLA, 650 Charles E. Young Drive East, Los Angeles, CA 90095, USA; (J.N.); (C.O.); (F.V.)
- Department of Chemistry and Biochemistry, University of California, 607 Charles E. Young Drive East, Los Angeles, CA 90095, USA
- Metabolism Theme, David Geffen School of Medicine, University of California, Los Angeles, CA 90095, USA
| | - Corey Osto
- Department of Medicine, Division of Endocrinology, David Geffen School of Medicine at UCLA, 650 Charles E. Young Drive East, Los Angeles, CA 90095, USA; (J.N.); (C.O.); (F.V.)
- Metabolism Theme, David Geffen School of Medicine, University of California, Los Angeles, CA 90095, USA
- Department of Molecular and Medical Pharmacology, David Geffen School of Medicine at UCLA, 650 Charles E. Young Drive East, Los Angeles, CA 90095, USA
| | - Frankie Villalobos
- Department of Medicine, Division of Endocrinology, David Geffen School of Medicine at UCLA, 650 Charles E. Young Drive East, Los Angeles, CA 90095, USA; (J.N.); (C.O.); (F.V.)
- Department of Integrative Biology and Physiology, University of California, Los Angeles, CA 90095, USA
| | - Orian S. Shirihai
- Department of Medicine, Division of Endocrinology, David Geffen School of Medicine at UCLA, 650 Charles E. Young Drive East, Los Angeles, CA 90095, USA; (J.N.); (C.O.); (F.V.)
- Metabolism Theme, David Geffen School of Medicine, University of California, Los Angeles, CA 90095, USA
- Department of Molecular and Medical Pharmacology, David Geffen School of Medicine at UCLA, 650 Charles E. Young Drive East, Los Angeles, CA 90095, USA
- Molecular Biology Institute, University of California, Los Angeles, CA 90095, USA
- Correspondence:
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16
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Mitochondrial Lipid Homeostasis at the Crossroads of Liver and Heart Diseases. Int J Mol Sci 2021; 22:ijms22136949. [PMID: 34203309 PMCID: PMC8268967 DOI: 10.3390/ijms22136949] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2021] [Revised: 06/19/2021] [Accepted: 06/25/2021] [Indexed: 12/16/2022] Open
Abstract
The prevalence of NAFLD (non-alcoholic fatty liver disease) is a rapidly increasing problem, affecting a huge population around the globe. However, CVDs (cardiovascular diseases) are the most common cause of mortality in NAFLD patients. Atherogenic dyslipidemia, characterized by plasma hypertriglyceridemia, increased small dense LDL (low-density lipoprotein) particles, and decreased HDL-C (high-density lipoprotein cholesterol) levels, is often observed in NAFLD patients. In this review, we summarize recent genetic evidence, proving the diverse nature of metabolic pathways involved in NAFLD pathogenesis. Analysis of available genetic data suggests that the altered operation of fatty-acid β-oxidation in liver mitochondria is the key process, connecting NAFLD-mediated dyslipidemia and elevated CVD risk. In addition, we discuss several NAFLD-associated genes with documented anti-atherosclerotic or cardioprotective effects, and current pharmaceutical strategies focused on both NAFLD treatment and reduction of CVD risk.
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17
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Gallardo-Montejano VI, Yang C, Hahner L, McAfee JL, Johnson JA, Holland WL, Fernandez-Valdivia R, Bickel PE. Perilipin 5 links mitochondrial uncoupled respiration in brown fat to healthy white fat remodeling and systemic glucose tolerance. Nat Commun 2021; 12:3320. [PMID: 34083525 PMCID: PMC8175597 DOI: 10.1038/s41467-021-23601-2] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2020] [Accepted: 04/28/2021] [Indexed: 02/06/2023] Open
Abstract
Exposure of mice or humans to cold promotes significant changes in brown adipose tissue (BAT) with respect to histology, lipid content, gene expression, and mitochondrial mass and function. Herein we report that the lipid droplet coat protein Perilipin 5 (PLIN5) increases markedly in BAT during exposure of mice to cold. To understand the functional significance of cold-induced PLIN5, we created and characterized gain- and loss-of-function mouse models. Enforcing PLIN5 expression in mouse BAT mimics the effects of cold with respect to mitochondrial cristae packing and uncoupled substrate-driven respiration. PLIN5 is necessary for the maintenance of mitochondrial cristae structure and respiratory function during cold stress. We further show that promoting PLIN5 function in BAT is associated with healthy remodeling of subcutaneous white adipose tissue and improvements in systemic glucose tolerance and diet-induced hepatic steatosis. These observations will inform future strategies that seek to exploit thermogenic adipose tissue as a therapeutic target for type 2 diabetes, obesity, and nonalcoholic fatty liver disease. Perilipin 5 is a lipid droplet protein that interacts with PGC1α in the nucleus to regulate mitochondrial metabolism. Here the authors use genetically engineered mouse models to determine the physiologic role of Perilipin 5, and show that it regulates mitochondrial adaptations to cold, as well as systemic energy metabolism.
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Affiliation(s)
- Violeta I Gallardo-Montejano
- Division of Endocrinology, Department of Internal Medicine, The University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Chaofeng Yang
- Division of Endocrinology, Department of Internal Medicine, The University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Lisa Hahner
- Division of Endocrinology, Department of Internal Medicine, The University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - John L McAfee
- Division of Endocrinology, Department of Internal Medicine, The University of Texas Southwestern Medical Center, Dallas, TX, USA.,Pathology and Laboratory Medicine Institute, Cleveland, OH, USA
| | - Joshua A Johnson
- Touchstone Diabetes Center, Department of Internal Medicine, The University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - William L Holland
- Touchstone Diabetes Center, Department of Internal Medicine, The University of Texas Southwestern Medical Center, Dallas, TX, USA.,Department of Nutrition and Integrative Physiology and the Diabetes and Metabolism Research Center, University of Utah, Salt Lake City, UT, USA
| | | | - Perry E Bickel
- Division of Endocrinology, Department of Internal Medicine, The University of Texas Southwestern Medical Center, Dallas, TX, USA.
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18
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Filali-Mouncef Y, Hunter C, Roccio F, Zagkou S, Dupont N, Primard C, Proikas-Cezanne T, Reggiori F. The ménage à trois of autophagy, lipid droplets and liver disease. Autophagy 2021; 18:50-72. [PMID: 33794741 PMCID: PMC8865253 DOI: 10.1080/15548627.2021.1895658] [Citation(s) in RCA: 118] [Impact Index Per Article: 39.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Autophagic pathways cross with lipid homeostasis and thus provide energy and essential building blocks that are indispensable for liver functions. Energy deficiencies are compensated by breaking down lipid droplets (LDs), intracellular organelles that store neutral lipids, in part by a selective type of autophagy, referred to as lipophagy. The process of lipophagy does not appear to be properly regulated in fatty liver diseases (FLDs), an important risk factor for the development of hepatocellular carcinomas (HCC). Here we provide an overview on our current knowledge of the biogenesis and functions of LDs, and the mechanisms underlying their lysosomal turnover by autophagic processes. This review also focuses on nonalcoholic steatohepatitis (NASH), a specific type of FLD characterized by steatosis, chronic inflammation and cell death. Particular attention is paid to the role of macroautophagy and macrolipophagy in relation to the parenchymal and non-parenchymal cells of the liver in NASH, as this disease has been associated with inappropriate lipophagy in various cell types of the liver.Abbreviations: ACAT: acetyl-CoA acetyltransferase; ACAC/ACC: acetyl-CoA carboxylase; AKT: AKT serine/threonine kinase; ATG: autophagy related; AUP1: AUP1 lipid droplet regulating VLDL assembly factor; BECN1/Vps30/Atg6: beclin 1; BSCL2/seipin: BSCL2 lipid droplet biogenesis associated, seipin; CMA: chaperone-mediated autophagy; CREB1/CREB: cAMP responsive element binding protein 1; CXCR3: C-X-C motif chemokine receptor 3; DAGs: diacylglycerols; DAMPs: danger/damage-associated molecular patterns; DEN: diethylnitrosamine; DGAT: diacylglycerol O-acyltransferase; DNL: de novo lipogenesis; EHBP1/NACSIN (EH domain binding protein 1); EHD2/PAST2: EH domain containing 2; CoA: coenzyme A; CCL/chemokines: chemokine ligands; CCl4: carbon tetrachloride; ER: endoplasmic reticulum; ESCRT: endosomal sorting complexes required for transport; FA: fatty acid; FFAs: free fatty acids; FFC: high saturated fats, fructose and cholesterol; FGF21: fibroblast growth factor 21; FITM/FIT: fat storage inducing transmembrane protein; FLD: fatty liver diseases; FOXO: forkhead box O; GABARAP: GABA type A receptor-associated protein; GPAT: glycerol-3-phosphate acyltransferase; HCC: hepatocellular carcinoma; HDAC6: histone deacetylase 6; HECT: homologous to E6-AP C-terminus; HFCD: high fat, choline deficient; HFD: high-fat diet; HSCs: hepatic stellate cells; HSPA8/HSC70: heat shock protein family A (Hsp70) member 8; ITCH/AIP4: itchy E3 ubiquitin protein ligase; KCs: Kupffer cells; LAMP2A: lysosomal associated membrane protein 2A; LDs: lipid droplets; LDL: low density lipoprotein; LEP/OB: leptin; LEPR/OBR: leptin receptor; LIPA/LAL: lipase A, lysosomal acid type; LIPE/HSL: lipase E, hormone sensitive type; LIR: LC3-interacting region; LPS: lipopolysaccharide; LSECs: liver sinusoidal endothelial cells; MAGs: monoacylglycerols; MAPK: mitogen-activated protein kinase; MAP3K5/ASK1: mitogen-activated protein kinase kinase kinase 5; MAP1LC3/LC3: microtubule associated protein 1 light chain 3; MCD: methionine-choline deficient; MGLL/MGL: monoglyceride lipase; MLXIPL/ChREBP: MLX interacting protein like; MTORC1: mechanistic target of rapamycin kinase complex 1; NAFLD: nonalcoholic fatty liver disease; NAS: NAFLD activity score; NASH: nonalcoholic steatohepatitis; NPC: NPC intracellular cholesterol transporter; NR1H3/LXRα: nuclear receptor subfamily 1 group H member 3; NR1H4/FXR: nuclear receptor subfamily 1 group H member 4; PDGF: platelet derived growth factor; PIK3C3/VPS34: phosphatidylinositol 3-kinase catalytic subunit type 3; PLIN: perilipin; PNPLA: patatin like phospholipase domain containing; PNPLA2/ATGL: patatin like phospholipase domain containing 2; PNPLA3/adiponutrin: patatin like phospholipase domain containing 3; PPAR: peroxisome proliferator activated receptor; PPARA/PPARα: peroxisome proliferator activated receptor alpha; PPARD/PPARδ: peroxisome proliferator activated receptor delta; PPARG/PPARγ: peroxisome proliferator activated receptor gamma; PPARGC1A/PGC1α: PPARG coactivator 1 alpha; PRKAA/AMPK: protein kinase AMP-activated catalytic subunit; PtdIns3K: class III phosphatidylinositol 3-kinase; PtdIns3P: phosphatidylinositol-3-phosphate; PTEN: phosphatase and tensin homolog; ROS: reactive oxygen species; SE: sterol esters; SIRT1: sirtuin 1; SPART/SPG20: spartin; SQSTM1/p62: sequestosome 1; SREBF1/SREBP1c: sterol regulatory element binding transcription factor 1; TAGs: triacylglycerols; TFE3: transcription factor binding to IGHM enhancer 3; TFEB: transcription factor EB; TGFB1/TGFβ: transforming growth factor beta 1; Ub: ubiquitin; UBE2G2/UBC7: ubiquitin conjugating enzyme E2 G2; ULK1/Atg1: unc-51 like autophagy activating kinase 1; USF1: upstream transcription factor 1; VLDL: very-low density lipoprotein; VPS: vacuolar protein sorting; WIPI: WD-repeat domain, phosphoinositide interacting; WDR: WD repeat domain.
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Affiliation(s)
- Yasmina Filali-Mouncef
- Department of Cell Biology, University of Groningen, University Medical Center Groningen, AV Groningen, The Netherlands
| | - Catherine Hunter
- Interfaculty Institute of Cell Biology, Eberhard Karls University Tuebingen, Tuebingen, Germany.,International Max Planck Research School 'From Molecules to Organisms', Max Planck Institute for Developmental Biology and Eberhard Karls University Tuebingen, Tuebingen, Germany
| | - Federica Roccio
- Institut Necker Enfants-Malades (INEM), INSERM U1151-CNRS UMR 8253, Université de Paris, Paris, France
| | - Stavroula Zagkou
- Adjuvatis, Lyon, France.,Laboratory of Tissue Biology and Therapeutic Engineering, CNRS UMR 5305, Université Claude Bernard Lyon 1, France
| | - Nicolas Dupont
- Institut Necker Enfants-Malades (INEM), INSERM U1151-CNRS UMR 8253, Université de Paris, Paris, France
| | | | - Tassula Proikas-Cezanne
- Interfaculty Institute of Cell Biology, Eberhard Karls University Tuebingen, Tuebingen, Germany.,International Max Planck Research School 'From Molecules to Organisms', Max Planck Institute for Developmental Biology and Eberhard Karls University Tuebingen, Tuebingen, Germany
| | - Fulvio Reggiori
- Department of Cell Biology, University of Groningen, University Medical Center Groningen, AV Groningen, The Netherlands
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Li L, Xie W, Gui Y, Zheng XL. Bromodomain-containing protein 4 and its role in cardiovascular diseases. J Cell Physiol 2020; 236:4829-4840. [PMID: 33345363 DOI: 10.1002/jcp.30225] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2020] [Revised: 12/03/2020] [Accepted: 12/07/2020] [Indexed: 12/22/2022]
Abstract
Bromodomain-containing protein 4 (BRD4), a chromatin-binding protein, is involved in the development of various tumors. Recent evidence suggests that BRD4 also plays a significant role in cardiovascular diseases, such as ischemic heart disease, hypertension, and cardiac hypertrophy. This review summarizes the roles of BRD4 as a potential regulator of various pathophysiological processes in cardiovascular diseases, implicating that BRD4 may be a new therapeutic target for cardiovascular diseases in the future.
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Affiliation(s)
- Liang Li
- Department of Pathophysiology, Institute of Cardiovascular Research, Key Laboratory for Atherosclerology of Hunan Province, Medical Research Center, Hunan Province Cooperative Innovation Center for Molecular Target New Drug Study, University of South China, Hengyang, Hunan, China.,Department of Biochemistry and Molecular Biology, Libin Cardiovascular Institute, Cumming School of Medicine, The University of Calgary, Calgary, Alberta, Canada
| | - Wei Xie
- Department of Biochemistry and Molecular Biology, Libin Cardiovascular Institute, Cumming School of Medicine, The University of Calgary, Calgary, Alberta, Canada.,Department of Anatomy, Clinical Anatomy & Reproductive Medicine Application Institute, University of South China, Hengyang, Hunan, China
| | - Yu Gui
- Department of Biochemistry and Molecular Biology, Libin Cardiovascular Institute, Cumming School of Medicine, The University of Calgary, Calgary, Alberta, Canada
| | - Xi-Long Zheng
- Department of Biochemistry and Molecular Biology, Libin Cardiovascular Institute, Cumming School of Medicine, The University of Calgary, Calgary, Alberta, Canada
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20
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Abstract
Background Mitochondrial oxidative function plays a key role in the development of non-alcoholic fatty liver disease (NAFLD) and insulin resistance (IR). Recent studies reported that fatty liver might not be a result of decreased mitochondrial fat oxidation caused by mitochondrial damage. Rather, NAFLD and IR induce an elevation in mitochondrial function that covers the increased demand for carbon intermediates and ATP caused by elevated lipogenesis and gluconeogenesis. Furthermore, mitochondria play a role in regulating hepatic insulin sensitivity and lipogenesis by modulating redox-sensitive signaling pathways. Scope of review We review the contradictory studies indicating that NAFLD and hyperglycemia can either increase or decrease mitochondrial oxidative capacity in the liver. We summarize mechanisms regulating mitochondrial heterogeneity inside the same cell and discuss how these mechanisms may determine the role of mitochondria in NAFLD. We further discuss the role of endogenous antioxidants in controlling mitochondrial H2O2 release and redox-mediated signaling. We describe the emerging concept that the subcellular location of cellular antioxidants is a key determinant of their effects on NAFLD. Major conclusions The balance of fat oxidation versus accumulation depends on mitochondrial fuel preference rather than ATP-synthesizing respiration. As such, therapies targeting fuel preference might be more suitable for treating NAFLD. Similarly, suppressing maladaptive antioxidants, rather than interfering with physiological mitochondrial H2O2-mediated signaling, may allow the maintenance of intact hepatic insulin signaling in NAFLD. Exploration of the subcellular compartmentalization of different antioxidant systems and the unique functions of specific mitochondrial subpopulations may offer new intervention points to treat NAFLD. Mitochondrial function has been reported to be increased or decreased in NAFLD. Functionally independent subpopulations of mitochondria can clarify the conundrum of these conflicting reports. Maladaptive antioxidants decreasing mitochondrial H2O2 and promoting NAFLD are discussed. Therapies targeting mitochondria to treat NAFLD are discussed.
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21
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EPA/DHA Concentrate by Urea Complexation Decreases Hyperinsulinemia and Increases Plin5 in the Liver of Mice Fed a High-Fat Diet. Molecules 2020; 25:molecules25143289. [PMID: 32698439 PMCID: PMC7397222 DOI: 10.3390/molecules25143289] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Revised: 06/27/2020] [Accepted: 07/15/2020] [Indexed: 12/14/2022] Open
Abstract
Dietary intake of eicosapentaenoic/docosahexaenoic acid (EPA/DHA) reduces insulin resistance and hepatic manifestations through the regulation of metabolism in the liver. Obese mice present insulin resistance and lipid accumulation in intracellular lipid droplets (LDs). LD-associated proteins perilipin (Plin) have an essential role in both adipogenesis and lipolysis; Plin5 regulates lipolysis and thus contributes to fat oxidation. The purpose of this study was to compare the effects of deodorized refined salmon oil (DSO) and its polyunsaturated fatty acids concentrate (CPUFA) containing EPA and DHA, obtained by complexing with urea, on obesity-induced metabolic alteration. CPUFA maximum content was determined using the Box-Behnken experimental design based on Surface Response Methodology. The optimized CPUFA was administered to high-fat diet (HFD)-fed mice (200 mg/kg/day of EPA + DHA) for 8 weeks. No significant differences (p > 0.05) in cholesterol, glycemia, LDs or transaminase content were found. Fasting insulin and hepatic Plin5 protein level increased in the group supplemented with the EPA + DHA optimized product (38.35 g/100 g total fatty acids) compared to obese mice without fish oil supplementation. The results suggest that processing salmon oil by urea concentration can generate an EPA+DHA dose useful to prevent the increase of fasting insulin and the decrease of Plin5 in the liver of insulin-resistant mice.
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22
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Arumugam MK, Talawar S, Listenberger L, Donohue TM, Osna NA, Kharbanda KK. Role of Elevated Intracellular S-Adenosylhomocysteine in the Pathogenesis of Alcohol-Related Liver Disease. Cells 2020; 9:cells9061526. [PMID: 32585865 PMCID: PMC7349643 DOI: 10.3390/cells9061526] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Revised: 06/19/2020] [Accepted: 06/21/2020] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND The earliest manifestation of alcohol-related liver disease (ALD) is steatosis, characterized by the accumulation of lipid droplets (LDs) in hepatocytes. Findings from our laboratory have indicated that many pathological changes, including steatosis, correlate with the alcohol-induced hepatocellular increases in S-adenosylhomocysteine (SAH). Based on these considerations, we hypothesized that an experimental increase in intracellular SAH alone will result in similar steatotic changes to those seen after alcohol exposure. METHODS Freshly isolated rat hepatocytes grown on collagen-coated plates were exposed to serum-free medium containing 50 µmol/L oleic acid and varying concentrations of 3-deazaadenosine (DZA) to experimentally elevate intracellular SAH levels. RESULTS Overnight exposure to DZA treatment dose-dependently increased hepatocellular triglyceride accumulation, which was also evident by morphological visualization of larger-sized LDs. The rise in triglycerides and LDs accompanied increases in mRNA and protein levels of several LD-associated proteins known to regulate LD number and size. Furthermore, DZA treatment caused a decline in the levels of lipases that prevent fat accumulation as well as increased the expression of factors involved in lipogenesis and fatty acid mobilization. Collectively, our results indicate that the elevation of intracellular SAH is sufficient to promote fat accumulation in hepatocytes, which is similar to that seen after alcohol exposure.
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Affiliation(s)
- Madan Kumar Arumugam
- Research Service, Veterans Affairs Nebraska-Western Iowa Health Care System, Omaha, NE 68105, USA; (M.K.A.); (S.T.); (T.M.D.J.); (N.A.O.)
- Department of Internal Medicine, University of Nebraska Medical Center, Omaha, NE 68198, USA
| | - Sharanappa Talawar
- Research Service, Veterans Affairs Nebraska-Western Iowa Health Care System, Omaha, NE 68105, USA; (M.K.A.); (S.T.); (T.M.D.J.); (N.A.O.)
- Department of Internal Medicine, University of Nebraska Medical Center, Omaha, NE 68198, USA
| | - Laura Listenberger
- Departments of Biology and Chemistry, St. Olaf College, Northfield, MN 55057, USA;
| | - Terrence M. Donohue
- Research Service, Veterans Affairs Nebraska-Western Iowa Health Care System, Omaha, NE 68105, USA; (M.K.A.); (S.T.); (T.M.D.J.); (N.A.O.)
- Department of Internal Medicine, University of Nebraska Medical Center, Omaha, NE 68198, USA
- Department of Biochemistry & Molecular Biology, University of Nebraska Medical Center, Omaha, NE 68198, USA
| | - Natalia A. Osna
- Research Service, Veterans Affairs Nebraska-Western Iowa Health Care System, Omaha, NE 68105, USA; (M.K.A.); (S.T.); (T.M.D.J.); (N.A.O.)
- Department of Internal Medicine, University of Nebraska Medical Center, Omaha, NE 68198, USA
| | - Kusum K. Kharbanda
- Research Service, Veterans Affairs Nebraska-Western Iowa Health Care System, Omaha, NE 68105, USA; (M.K.A.); (S.T.); (T.M.D.J.); (N.A.O.)
- Department of Internal Medicine, University of Nebraska Medical Center, Omaha, NE 68198, USA
- Department of Biochemistry & Molecular Biology, University of Nebraska Medical Center, Omaha, NE 68198, USA
- Correspondence: ; Tel.: +1-402-995-3752; Fax: +1-402-995-4600
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23
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Deletion of Perilipin 5 Protects Against Hepatic Injury in Nonalcoholic Fatty Liver Disease via Missing Inflammasome Activation. Cells 2020; 9:cells9061346. [PMID: 32481590 PMCID: PMC7348929 DOI: 10.3390/cells9061346] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Revised: 05/22/2020] [Accepted: 05/25/2020] [Indexed: 12/21/2022] Open
Abstract
Nonalcoholic fatty liver disease (NAFLD) is a leading cause of chronic liver diseases with an increasing prevalence due to rising rates of obesity, metabolic syndrome and type II diabetes. Untreated NAFLD may progress to steatohepatitis (NASH) and ultimately liver cirrhosis. NAFLD is characterized by lipid accumulation, and when sufficient excess lipids are obtained, irreversible liver injury may follow. Perilipin 5 (PLIN5), a known lipid droplet coating protein and triglyceride metabolism regulator, is highly expressed in oxidatively modified tissues but it is still unclear how it affects NAFLD/NASH progress. We here studied how PLIN5 affects NAFLD development induced by a 30-week high-fat diet (HFD) administration in wild type and PLIN5 knock out (Plin5−/−) mice. The disruption of PLIN5 induced differences in lipid metabolism during HFD feeding and was associated with reduced hepatic fat accumulation. Surprisingly, Plin5−/− mice showed mitigated activation of the NLR family pyrin domain-containing 3 (NLRP3) inflammasome, leading to minor hepatic damage. We conclude that PLIN5 is a pleiotropic regulator of hepatic homeostasis in NASH development. Targeting the PLIN5 expression appears critical for protecting the liver from inflammatory activation during chronic NAFLD.
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24
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Turpin-Nolan SM, Brüning JC. The role of ceramides in metabolic disorders: when size and localization matters. Nat Rev Endocrinol 2020; 16:224-233. [PMID: 32060415 DOI: 10.1038/s41574-020-0320-5] [Citation(s) in RCA: 99] [Impact Index Per Article: 24.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 01/13/2020] [Indexed: 01/21/2023]
Abstract
Ceramide accumulation is a hallmark in the manifestation of numerous obesity-related diseases, such as type 2 diabetes mellitus and atherosclerosis. Until the early 2000s, ceramides were viewed as a homogenous class of sphingolipids. However, it has now become clear that ceramides exert fundamentally different effects depending on the specific fatty acyl chain lengths, which are integrated into ceramides by a group of enzymes known as dihydroceramide synthases. In addition, alterations in ceramide synthesis, trafficking and metabolism in specific cellular compartments exert distinct consequences on metabolic homeostasis. Here, we examine the emerging concept of how the intracellular localization of ceramides with distinct acyl chain lengths can regulate glucose metabolism, thus emphasizing their potential as targets in the development of novel and specific therapies for obesity and obesity-associated diseases.
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Affiliation(s)
- Sarah M Turpin-Nolan
- Max Planck Institute for Metabolism Research, Köln, Germany
- Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria, Australia
- Cologne Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD), Köln, Germany
| | - Jens C Brüning
- Max Planck Institute for Metabolism Research, Köln, Germany.
- Cologne Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD), Köln, Germany.
- Centre for Molecular Medicine Cologne (CMMC), Köln, Germany.
- Centre for Endocrinology, Diabetes and Preventive Medicine (CEDP), University Hospital Cologne, Köln, Germany.
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25
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Zhang E, Cui W, Lopresti M, Mashek MT, Najt CP, Hu H, Mashek DG. Hepatic PLIN5 signals via SIRT1 to promote autophagy and prevent inflammation during fasting. J Lipid Res 2020; 61:338-350. [PMID: 31932301 DOI: 10.1194/jlr.ra119000336] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2019] [Revised: 01/09/2020] [Indexed: 01/04/2023] Open
Abstract
Lipid droplets (LDs) are energy-storage organelles that are coated with hundreds of proteins, including members of the perilipin (PLIN) family. PLIN5 is highly expressed in oxidative tissues, including the liver, and is thought to play a key role in uncoupling LD accumulation from lipotoxicity; however, the mechanisms behind this action are incompletely defined. We investigated the role of hepatic PLIN5 in inflammation and lipotoxicity in a murine model under both fasting and refeeding conditions and in hepatocyte cultures. PLIN5 ablation with antisense oligonucleotides triggered a pro-inflammatory response in livers from mice only under fasting conditions. Similarly, PLIN5 mitigated lipopolysaccharide- or palmitic acid-induced inflammatory responses in hepatocytes. During fasting, PLIN5 was also required for the induction of autophagy, which contributed to its anti-inflammatory effects. The ability of PLIN5 to promote autophagy and prevent inflammation were dependent upon signaling through sirtuin 1 (SIRT1), which is known to be activated in response to nuclear PLIN5 under fasting conditions. Taken together, these data show that PLIN5 signals via SIRT1 to promote autophagy and prevent FA-induced inflammation as a means to maintain hepatocyte homeostasis during periods of fasting and FA mobilization.
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Affiliation(s)
- Enxiang Zhang
- Beijing Advanced Innovation Center for Food Nutrition and Human Health, College of Food Science and Nutritional Engineering, China Agricultural University, Beijing, People's Republic of China.,Departments of Biochemistry, Molecular Biology, and Biophysics Division of Diabetes, Endocrinology, and Metabolism, University of Minnesota, Minneapolis, MN
| | - Wenqi Cui
- Departments of Biochemistry, Molecular Biology, and Biophysics Division of Diabetes, Endocrinology, and Metabolism, University of Minnesota, Minneapolis, MN
| | - Michael Lopresti
- Departments of Biochemistry, Molecular Biology, and Biophysics Division of Diabetes, Endocrinology, and Metabolism, University of Minnesota, Minneapolis, MN
| | - Mara T Mashek
- Departments of Biochemistry, Molecular Biology, and Biophysics Division of Diabetes, Endocrinology, and Metabolism, University of Minnesota, Minneapolis, MN
| | - Charles P Najt
- Departments of Biochemistry, Molecular Biology, and Biophysics Division of Diabetes, Endocrinology, and Metabolism, University of Minnesota, Minneapolis, MN
| | - Hongbo Hu
- Beijing Advanced Innovation Center for Food Nutrition and Human Health, College of Food Science and Nutritional Engineering, China Agricultural University, Beijing, People's Republic of China
| | - Douglas G Mashek
- Departments of Biochemistry, Molecular Biology, and Biophysics Division of Diabetes, Endocrinology, and Metabolism, University of Minnesota, Minneapolis, MN .,Medicine , Division of Diabetes, Endocrinology, and Metabolism, University of Minnesota, Minneapolis, MN
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26
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Challa TD, Wueest S, Lucchini FC, Dedual M, Modica S, Borsigova M, Wolfrum C, Blüher M, Konrad D. Liver ASK1 protects from non-alcoholic fatty liver disease and fibrosis. EMBO Mol Med 2019; 11:e10124. [PMID: 31595673 PMCID: PMC6783644 DOI: 10.15252/emmm.201810124] [Citation(s) in RCA: 59] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2018] [Revised: 04/30/2019] [Accepted: 05/03/2019] [Indexed: 12/15/2022] Open
Abstract
Non-alcoholic fatty liver disease (NAFLD) is strongly associated with obesity and may progress to non-alcoholic steatohepatitis (NASH) and liver fibrosis. The deficit of pharmacological therapies for the latter mainly results from an incomplete understanding of involved pathological mechanisms. Herein, we identify apoptosis signal-regulating kinase 1 (ASK1) as a suppressor of NASH and fibrosis formation. High-fat diet-fed and aged chow-fed liver-specific ASK1-knockout mice develop a higher degree of hepatic steatosis, inflammation, and fibrosis compared to controls. In addition, pharmacological inhibition of ASK1 increased hepatic lipid accumulation in wild-type mice. In line, liver-specific ASK1 overexpression protected mice from the development of high-fat diet-induced hepatic steatosis and carbon tetrachloride-induced fibrosis. Mechanistically, ASK1 depletion blunts autophagy, thereby enhancing lipid droplet accumulation and liver fibrosis. In human livers of lean and obese subjects, ASK1 expression correlated negatively with liver fat content and NASH scores, but positively with markers for autophagy. Taken together, ASK1 may be a novel therapeutic target to tackle NAFLD and liver fibrosis.
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Affiliation(s)
- Tenagne D Challa
- Division of Pediatric Endocrinology and DiabetologyUniversity Children's HospitalZurichSwitzerland
- Children's Research CenterUniversity Children's HospitalZurichSwitzerland
| | - Stephan Wueest
- Division of Pediatric Endocrinology and DiabetologyUniversity Children's HospitalZurichSwitzerland
- Children's Research CenterUniversity Children's HospitalZurichSwitzerland
| | - Fabrizio C Lucchini
- Division of Pediatric Endocrinology and DiabetologyUniversity Children's HospitalZurichSwitzerland
- Children's Research CenterUniversity Children's HospitalZurichSwitzerland
- Zurich Center for Integrative Human PhysiologyUniversity of ZurichZurichSwitzerland
| | - Mara Dedual
- Division of Pediatric Endocrinology and DiabetologyUniversity Children's HospitalZurichSwitzerland
- Children's Research CenterUniversity Children's HospitalZurichSwitzerland
- Zurich Center for Integrative Human PhysiologyUniversity of ZurichZurichSwitzerland
| | - Salvatore Modica
- Institute of Food, Nutrition and HealthETH ZurichSchwerzenbachSwitzerland
| | - Marcela Borsigova
- Division of Pediatric Endocrinology and DiabetologyUniversity Children's HospitalZurichSwitzerland
- Children's Research CenterUniversity Children's HospitalZurichSwitzerland
| | - Christian Wolfrum
- Institute of Food, Nutrition and HealthETH ZurichSchwerzenbachSwitzerland
| | | | - Daniel Konrad
- Division of Pediatric Endocrinology and DiabetologyUniversity Children's HospitalZurichSwitzerland
- Children's Research CenterUniversity Children's HospitalZurichSwitzerland
- Zurich Center for Integrative Human PhysiologyUniversity of ZurichZurichSwitzerland
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27
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Haemmerle G, Lass A. Genetically modified mouse models to study hepatic neutral lipid mobilization. Biochim Biophys Acta Mol Basis Dis 2019; 1865:879-894. [PMID: 29883718 PMCID: PMC6887554 DOI: 10.1016/j.bbadis.2018.06.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2018] [Revised: 05/25/2018] [Accepted: 06/01/2018] [Indexed: 02/07/2023]
Abstract
Excessive accumulation of triacylglycerol is the common denominator of a wide range of clinical pathologies of liver diseases, termed non-alcoholic fatty liver disease. Such excessive triacylglycerol deposition in the liver is also referred to as hepatic steatosis. Although liver steatosis often resolves over time, it eventually progresses to steatohepatitis, liver fibrosis and cirrhosis, with associated complications, including liver failure, hepatocellular carcinoma and ultimately death of affected individuals. From the disease etiology it is obvious that a tight regulation between lipid uptake, triacylglycerol synthesis, hydrolysis, secretion and fatty acid oxidation is required to prevent triacylglycerol deposition in the liver. In addition to triacylglycerol, also a tight control of other neutral lipid ester classes, i.e. cholesteryl esters and retinyl esters, is crucial for the maintenance of a healthy liver. Excessive cholesteryl ester accumulation is a hallmark of cholesteryl ester storage disease or Wolman disease, which is associated with premature death. The loss of hepatic vitamin A stores (retinyl ester stores of hepatic stellate cells) is incidental to the onset of liver fibrosis. Importantly, this more advanced stage of liver disease usually does not resolve but progresses to life threatening stages, i.e. liver cirrhosis and cancer. Therefore, understanding the enzymes and pathways that mobilize hepatic neutral lipid esters is crucial for the development of strategies and therapies to ameliorate pathophysiological conditions associated with derangements of hepatic neutral lipid ester stores, including liver steatosis, steatohepatitis, and fibrosis. This review highlights the physiological roles of enzymes governing the mobilization of neutral lipid esters at different sites in liver cells, including cytosolic lipid droplets, endoplasmic reticulum, and lysosomes. This article is part of a Special Issue entitled Molecular Basis of Disease: Animal models in liver disease.
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Affiliation(s)
- Guenter Haemmerle
- Institute of Molecular Biosciences, University of Graz, Heinrichstraße 31/II, 8010 Graz, Austria.
| | - Achim Lass
- Institute of Molecular Biosciences, University of Graz, Heinrichstraße 31/II, 8010 Graz, Austria; BioTechMed-Graz, Austria.
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28
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Benador IY, Veliova M, Liesa M, Shirihai OS. Mitochondria Bound to Lipid Droplets: Where Mitochondrial Dynamics Regulate Lipid Storage and Utilization. Cell Metab 2019; 29:827-835. [PMID: 30905670 PMCID: PMC6476311 DOI: 10.1016/j.cmet.2019.02.011] [Citation(s) in RCA: 166] [Impact Index Per Article: 33.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/23/2018] [Revised: 01/21/2019] [Accepted: 02/21/2019] [Indexed: 01/09/2023]
Abstract
The isolation and biochemical characterization of lipid droplet (LD)-associated mitochondria revealed the capacity of the cell to produce and maintain distinct mitochondrial populations carrying disparate proteome and dissimilar capacities to oxidize fatty acids and pyruvate. With mitochondrial motility being a central parameter determining mitochondrial fusion, adherence to LDs provides a mechanism by which peridroplet mitochondria (PDM) remain segregated from cytoplasmic mitochondria (CM). The existence of metabolically distinct subpopulations provides an explanation for the capacity of mitochondria within the individual cell to be involved simultaneously in fatty acid oxidation and LD formation. The mechanisms that deploy mitochondria to the LD and the dysfunctions that result from unbalanced proportions of PDM and CM remain to be explored. Understanding the roles and regulation of mitochondrial tethering to LDs offers new points of intervention in metabolic diseases.
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Affiliation(s)
- Ilan Y Benador
- Division of Endocrinology, Department of Medicine, and Department of Molecular and Medical Pharmacology, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA; Obesity Research Center, Department of Medicine, Boston University School of Medicine, Boston, MA, USA
| | - Michaela Veliova
- Division of Endocrinology, Department of Medicine, and Department of Molecular and Medical Pharmacology, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
| | - Marc Liesa
- Division of Endocrinology, Department of Medicine, and Department of Molecular and Medical Pharmacology, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA; UCLA Molecular Biology Institute, Los Angeles, CA, USA.
| | - Orian S Shirihai
- Division of Endocrinology, Department of Medicine, and Department of Molecular and Medical Pharmacology, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA; Obesity Research Center, Department of Medicine, Boston University School of Medicine, Boston, MA, USA.
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Keenan SN, Meex RC, Lo JCY, Ryan A, Nie S, Montgomery MK, Watt MJ. Perilipin 5 Deletion in Hepatocytes Remodels Lipid Metabolism and Causes Hepatic Insulin Resistance in Mice. Diabetes 2019; 68:543-555. [PMID: 30617219 DOI: 10.2337/db18-0670] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/15/2018] [Accepted: 12/13/2018] [Indexed: 11/13/2022]
Abstract
Defects in hepatic lipid metabolism cause nonalcoholic fatty liver disease and insulin resistance, and these pathologies are closely linked. Regulation of lipid droplet metabolism is central to the control of intracellular fatty acid fluxes, and perilipin 5 (PLIN5) is important in this process. We examined the role of PLIN5 on hepatic lipid metabolism and systemic glycemic control using liver-specific Plin5-deficient mice (Plin5LKO ). Hepatocytes isolated from Plin5LKO mice exhibited marked changes in lipid metabolism characterized by decreased fatty acid uptake and storage, decreased fatty acid oxidation that was associated with reduced contact between lipid droplets and mitochondria, and reduced triglyceride secretion. With consumption of a high-fat diet, Plin5LKO mice accumulated intrahepatic triglyceride, without significant changes in inflammation, ceramide or diglyceride contents, endoplasmic reticulum stress, or autophagy. Instead, livers of Plin5LKO mice exhibited activation of c-Jun N-terminal kinase, impaired insulin signal transduction, and insulin resistance, which impaired systemic insulin action and glycemic control. Re-expression of Plin5 in the livers of Plin5LKO mice reversed these effects. Together, we show that Plin5 is an important modulator of intrahepatic lipid metabolism and suggest that the increased Plin5 expression that occurs with overnutrition may play an important role in preventing hepatic insulin resistance.
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Affiliation(s)
- Stacey N Keenan
- Metabolism, Diabetes and Obesity Program, Monash Biomedicine Discovery Institute, and Department of Physiology, Monash University, Clayton, Victoria, Australia
| | - Ruth C Meex
- Metabolism, Diabetes and Obesity Program, Monash Biomedicine Discovery Institute, and Department of Physiology, Monash University, Clayton, Victoria, Australia
- Department of Human Biology, School of Nutrition and Translational Research in Metabolism (NUTRIM), Faculty of Health, Medicine and Life Sciences, Maastricht University Medical Centre, Maastricht, the Netherlands
| | - Jennifer C Y Lo
- Metabolism, Diabetes and Obesity Program, Monash Biomedicine Discovery Institute, and Department of Physiology, Monash University, Clayton, Victoria, Australia
| | - Andrew Ryan
- TissuPath, Mount Waverley, Victoria, Australia
| | - Shuai Nie
- Melbourne Mass Spectrometry and Proteomics Facility, Bio21 Molecular Science & Biotechnology Institute, The University of Melbourne, Melbourne, Victoria, Australia
| | - Magdalene K Montgomery
- Metabolism, Diabetes and Obesity Program, Monash Biomedicine Discovery Institute, and Department of Physiology, Monash University, Clayton, Victoria, Australia
- Department of Physiology, The University of Melbourne, Melbourne, Victoria, Australia
| | - Matthew J Watt
- Metabolism, Diabetes and Obesity Program, Monash Biomedicine Discovery Institute, and Department of Physiology, Monash University, Clayton, Victoria, Australia
- Department of Physiology, The University of Melbourne, Melbourne, Victoria, Australia
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30
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Petersen MC, Shulman GI. Mechanisms of Insulin Action and Insulin Resistance. Physiol Rev 2018; 98:2133-2223. [PMID: 30067154 PMCID: PMC6170977 DOI: 10.1152/physrev.00063.2017] [Citation(s) in RCA: 1440] [Impact Index Per Article: 240.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2017] [Revised: 03/22/2018] [Accepted: 03/24/2018] [Indexed: 12/15/2022] Open
Abstract
The 1921 discovery of insulin was a Big Bang from which a vast and expanding universe of research into insulin action and resistance has issued. In the intervening century, some discoveries have matured, coalescing into solid and fertile ground for clinical application; others remain incompletely investigated and scientifically controversial. Here, we attempt to synthesize this work to guide further mechanistic investigation and to inform the development of novel therapies for type 2 diabetes (T2D). The rational development of such therapies necessitates detailed knowledge of one of the key pathophysiological processes involved in T2D: insulin resistance. Understanding insulin resistance, in turn, requires knowledge of normal insulin action. In this review, both the physiology of insulin action and the pathophysiology of insulin resistance are described, focusing on three key insulin target tissues: skeletal muscle, liver, and white adipose tissue. We aim to develop an integrated physiological perspective, placing the intricate signaling effectors that carry out the cell-autonomous response to insulin in the context of the tissue-specific functions that generate the coordinated organismal response. First, in section II, the effectors and effects of direct, cell-autonomous insulin action in muscle, liver, and white adipose tissue are reviewed, beginning at the insulin receptor and working downstream. Section III considers the critical and underappreciated role of tissue crosstalk in whole body insulin action, especially the essential interaction between adipose lipolysis and hepatic gluconeogenesis. The pathophysiology of insulin resistance is then described in section IV. Special attention is given to which signaling pathways and functions become insulin resistant in the setting of chronic overnutrition, and an alternative explanation for the phenomenon of ‟selective hepatic insulin resistanceˮ is presented. Sections V, VI, and VII critically examine the evidence for and against several putative mediators of insulin resistance. Section V reviews work linking the bioactive lipids diacylglycerol, ceramide, and acylcarnitine to insulin resistance; section VI considers the impact of nutrient stresses in the endoplasmic reticulum and mitochondria on insulin resistance; and section VII discusses non-cell autonomous factors proposed to induce insulin resistance, including inflammatory mediators, branched-chain amino acids, adipokines, and hepatokines. Finally, in section VIII, we propose an integrated model of insulin resistance that links these mediators to final common pathways of metabolite-driven gluconeogenesis and ectopic lipid accumulation.
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Affiliation(s)
- Max C Petersen
- Departments of Internal Medicine and Cellular & Molecular Physiology, Howard Hughes Medical Institute, Yale University School of Medicine , New Haven, Connecticut
| | - Gerald I Shulman
- Departments of Internal Medicine and Cellular & Molecular Physiology, Howard Hughes Medical Institute, Yale University School of Medicine , New Haven, Connecticut
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31
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Apostolopoulou M, Gordillo R, Koliaki C, Gancheva S, Jelenik T, De Filippo E, Herder C, Markgraf D, Jankowiak F, Esposito I, Schlensak M, Scherer PE, Roden M. Specific Hepatic Sphingolipids Relate to Insulin Resistance, Oxidative Stress, and Inflammation in Nonalcoholic Steatohepatitis. Diabetes Care 2018; 41:1235-1243. [PMID: 29602794 DOI: 10.2337/dc17-1318] [Citation(s) in RCA: 183] [Impact Index Per Article: 30.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/01/2017] [Accepted: 03/06/2018] [Indexed: 02/03/2023]
Abstract
OBJECTIVE Insulin resistance and nonalcoholic fatty liver disease have been linked to several lipid metabolites in animals, but their role in humans remains unclear. This study examined the relationship of sphingolipids with hepatic and peripheral metabolism in 21 insulin-resistant obese patients without (NAFL-) or with (NAFL+) nonalcoholic fatty liver and nonalcoholic steatohepatitis (NASH) and 7 healthy lean individuals undergoing tissue biopsies during bariatric or elective abdominal surgery. RESEARCH DESIGN AND METHODS Hyperinsulinemic-euglycemic clamps with d-[6,6-2H2]glucose were performed to quantify tissue-specific insulin sensitivity. Hepatic oxidative capacity, lipid peroxidation, and the phosphorylated-to-total c-Jun N-terminal kinase (pJNK-to-tJNK) ratio were measured to assess mitochondrial function, oxidative stress, and inflammatory activity. RESULTS Hepatic total ceramides were higher by 50% and 33% in NASH compared with NAFL+ and NAFL-, respectively. Only in NASH were hepatic dihydroceramides (16:0, 22:0, and 24:1) and lactosylceramides increased. Serum total ceramides and dihydroceramides (hepatic dihydroceramides 22:0 and 24:1) correlated negatively with whole-body but not with hepatic insulin sensitivity. Hepatic maximal respiration related positively to serum lactosylceramide subspecies, hepatic sphinganine, and lactosylceramide 14:0. Liver lipid peroxides (total ceramides, sphingomyelin 22:0) and the pJNK-to-tJNK ratio (ceramide 24:0; hexosylceramides 22:0, 24:0, and 24:1) all positively correlated with the respective hepatic sphingolipids. CONCLUSIONS Sphingolipid species are not only increased in insulin-resistant humans with NASH but also correlate with hepatic oxidative stress and inflammation, suggesting that these lipids may play a role during progression of simple steatosis to NASH in humans.
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Affiliation(s)
- Maria Apostolopoulou
- Division of Endocrinology and Diabetology, Medical Faculty, Heinrich-Heine University, Düsseldorf, Germany.,Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research at Heinrich-Heine University, Düsseldorf, Germany.,German Center for Diabetes Research, München-Neuherberg, Germany
| | - Ruth Gordillo
- Touchstone Diabetes Center, Department of Internal Medicine, The University of Texas Southwestern Medical Center, Dallas, TX
| | - Chrysi Koliaki
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research at Heinrich-Heine University, Düsseldorf, Germany.,German Center for Diabetes Research, München-Neuherberg, Germany
| | - Sofia Gancheva
- Division of Endocrinology and Diabetology, Medical Faculty, Heinrich-Heine University, Düsseldorf, Germany.,Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research at Heinrich-Heine University, Düsseldorf, Germany.,German Center for Diabetes Research, München-Neuherberg, Germany
| | - Tomas Jelenik
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research at Heinrich-Heine University, Düsseldorf, Germany.,German Center for Diabetes Research, München-Neuherberg, Germany
| | - Elisabetta De Filippo
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research at Heinrich-Heine University, Düsseldorf, Germany.,German Center for Diabetes Research, München-Neuherberg, Germany
| | - Christian Herder
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research at Heinrich-Heine University, Düsseldorf, Germany.,German Center for Diabetes Research, München-Neuherberg, Germany
| | - Daniel Markgraf
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research at Heinrich-Heine University, Düsseldorf, Germany.,German Center for Diabetes Research, München-Neuherberg, Germany
| | - Frank Jankowiak
- Institute of Pathology, Medical Faculty, Heinrich-Heine University, Düsseldorf, Germany
| | - Irene Esposito
- Institute of Pathology, Medical Faculty, Heinrich-Heine University, Düsseldorf, Germany
| | | | - Philipp E Scherer
- Touchstone Diabetes Center, Department of Internal Medicine, The University of Texas Southwestern Medical Center, Dallas, TX
| | - Michael Roden
- Division of Endocrinology and Diabetology, Medical Faculty, Heinrich-Heine University, Düsseldorf, Germany .,Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research at Heinrich-Heine University, Düsseldorf, Germany.,German Center for Diabetes Research, München-Neuherberg, Germany
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32
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Hashani M, Witzel HR, Pawella LM, Lehmann-Koch J, Schumacher J, Mechtersheimer G, Schnölzer M, Schirmacher P, Roth W, Straub BK. Widespread expression of perilipin 5 in normal human tissues and in diseases is restricted to distinct lipid droplet subpopulations. Cell Tissue Res 2018; 374:121-136. [PMID: 29752569 DOI: 10.1007/s00441-018-2845-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2017] [Accepted: 04/18/2018] [Indexed: 12/18/2022]
Abstract
Diseases associated with the accumulation of lipid droplets are increasing in western countries. Lipid droplet biogenesis, structure and degradation are regulated by proteins of the perilipin family. Perilipin 5 has been shown to regulate basal lipolysis in oxidative tissues. We examine perilipin 5 in normal human tissues and in diseases using protein biochemical and microscopic techniques. Perilipin 5 was constitutively located at small lipid droplets in skeletal myocytes, cardiomyocytes and brown adipocytes. In addition, perilipin 5 was detected in the epithelia of the gastrointestinal and urogenital tract, especially in hepatocytes, the mitochondria-rich parietal cells of the stomach, tubular kidney cells and ductal cells of the salivary gland and pancreas. Granular cytoplasmic expression, without a lipid droplet-bound localization was detected elsewhere. In cardiomyopathies, in skeletal muscle diseases and during hepatocyte steatogenesis, perilipin 5 was upregulated and localized to larger and more numerous lipid droplets. In steatotic human hepatocytes, perilipin 5 was moderately increased and colocalized with perilipins 1 and 2 but not with perilipin 3 at lipid droplets. In liver diseases implicated in alterations of mitochondria, such as mitochondriopathies, alcoholic liver disease, Wilson's disease and acute liver injury, perilipin 5 was frequently localized to small lipid droplets and less in the cytoplasm. In tumorigenesis, perilipin 5 was especially upregulated in lipo-, leio- and rhabdomyosarcoma and hepatocellular and renal cell carcinoma. In summary, our study provides evidence that perilipin 5 is not restricted to certain cell types but localizes to distinct lipid droplet subpopulations reflecting a possible function in oxidative energy supply in normal tissues and in diseases.
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Affiliation(s)
- Merita Hashani
- Department of General Pathology, Institute of Pathology, University Hospital, Heidelberg, Germany.,Institute of Pathology, University Hospital of Prishtina, Prishtina, Kosovo
| | - Hagen Roland Witzel
- Institute of Pathology, University Medicine, Johannes Gutenberg-University Mainz, Langenbeckstr. 1, 55131, Mainz, Germany
| | - Lena Maria Pawella
- Department of General Pathology, Institute of Pathology, University Hospital, Heidelberg, Germany
| | - Judith Lehmann-Koch
- Department of General Pathology, Institute of Pathology, University Hospital, Heidelberg, Germany
| | - Jens Schumacher
- Department of Internal Medicine III, Division of Translational and Experimental Oncology, University Hospital Mainz, Mainz, Germany
| | - Gunhild Mechtersheimer
- Department of General Pathology, Institute of Pathology, University Hospital, Heidelberg, Germany
| | - Martina Schnölzer
- Functional Proteome Analysis, German Cancer Research Center Heidelberg (DKFZ), INF 580, Heidelberg, Germany
| | - Peter Schirmacher
- Department of General Pathology, Institute of Pathology, University Hospital, Heidelberg, Germany
| | - Wilfried Roth
- Institute of Pathology, University Medicine, Johannes Gutenberg-University Mainz, Langenbeckstr. 1, 55131, Mainz, Germany
| | - Beate Katharina Straub
- Department of General Pathology, Institute of Pathology, University Hospital, Heidelberg, Germany. .,Institute of Pathology, University Medicine, Johannes Gutenberg-University Mainz, Langenbeckstr. 1, 55131, Mainz, Germany.
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33
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Petersen MC, Shulman GI. Roles of Diacylglycerols and Ceramides in Hepatic Insulin Resistance. Trends Pharmacol Sci 2017; 38:649-665. [PMID: 28551355 DOI: 10.1016/j.tips.2017.04.004] [Citation(s) in RCA: 245] [Impact Index Per Article: 35.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2017] [Revised: 04/19/2017] [Accepted: 04/20/2017] [Indexed: 12/22/2022]
Abstract
Although ample evidence links hepatic lipid accumulation with hepatic insulin resistance, the mechanistic basis of this association is incompletely understood and controversial. Diacylglycerols (DAGs) and ceramides have emerged as the two best-studied putative mediators of lipid-induced hepatic insulin resistance. Both lipids were first associated with insulin resistance in skeletal muscle and were subsequently hypothesized to mediate insulin resistance in the liver. However, the putative roles for DAGs and ceramides in hepatic insulin resistance have proved more complex than originally imagined, with various genetic and pharmacologic manipulations yielding a vast and occasionally contradictory trove of data to sort. In this review we examine the state of this field, turning a critical eye toward both DAGs and ceramides as putative mediators of lipid-induced hepatic insulin resistance.
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Affiliation(s)
- Max C Petersen
- Department of Cellular and Molecular Physiology, Yale University School of Medicine, New Haven, CT 06520, USA
| | - Gerald I Shulman
- Department of Cellular and Molecular Physiology, Yale University School of Medicine, New Haven, CT 06520, USA; Department of Internal Medicine, Yale University School of Medicine, New Haven, CT 06520, USA; Howard Hughes Medical Institute, Yale University School of Medicine, New Haven, CT 06520, USA.
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34
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Peters HPF, Schrauwen P, Verhoef P, Byrne CD, Mela DJ, Pfeiffer AFH, Risérus U, Rosendaal FR, Schrauwen-Hinderling V. Liver fat: a relevant target for dietary intervention? Summary of a Unilever workshop. J Nutr Sci 2017; 6:e15. [PMID: 28630692 PMCID: PMC5468740 DOI: 10.1017/jns.2017.13] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2016] [Accepted: 03/09/2017] [Indexed: 12/20/2022] Open
Abstract
Currently it is estimated that about 1 billion people globally have non-alcoholic fatty liver disease (NAFLD), a condition in which liver fat exceeds 5 % of liver weight in the absence of significant alcohol intake. Due to the central role of the liver in metabolism, the prevalence of NAFLD is increasing in parallel with the prevalence of obesity, insulin resistance and other risk factors of metabolic diseases. However, the contribution of liver fat to the risk of type 2 diabetes mellitus and CVD, relative to other ectopic fat depots and to other risk markers, is unclear. Various studies have suggested that the accumulation of liver fat can be reduced or prevented via dietary changes. However, the amount of liver fat reduction that would be physiologically relevant, and the timeframes and dose-effect relationships for achieving this through different diet-based approaches, are unclear. Also, it is still uncertain whether the changes in liver fat per se or the associated metabolic changes are relevant. Furthermore, the methods available to measure liver fat, or even individual fatty acids, differ in sensitivity and reliability. The present report summarises key messages of presentations from different experts and related discussions from a workshop intended to capture current views and research gaps relating to the points above.
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Affiliation(s)
- Harry P. F. Peters
- Unilever R&D Vlaardingen, Olivier van Noortlaan 120, Vlaardingen, The Netherlands
| | - Patrick Schrauwen
- Department of Human Biology, NUTRIM School for Nutrition and Translational Research in Metabolism, Maastricht University Medical Center, Maastricht, The Netherlands
| | - Petra Verhoef
- Unilever R&D Vlaardingen, Olivier van Noortlaan 120, Vlaardingen, The Netherlands
| | - Christopher D. Byrne
- Nutrition and Metabolism, Faculty of Medicine, University of Southampton & Southampton National Institute for Health Research Biomedical Research Centre, University Hospital Southampton, Southampton, UK
| | - David J. Mela
- Unilever R&D Vlaardingen, Olivier van Noortlaan 120, Vlaardingen, The Netherlands
| | - Andreas F. H. Pfeiffer
- Department of Endocrinology, Diabetes and Nutrition, Charité Universitätsmedizin Berlin, Campus Benjamin Franklin, Berlin
- Department of Clinical Nutrition, German Institute of Human Nutrition, Potsdam and German Center for Diabetes Research, DZD, Neuherberg, Germany
| | - Ulf Risérus
- Department of Public Health and Caring Sciences, Clinical Nutrition and Metabolism Unit, Uppsala University, Sweden
| | - Frits R. Rosendaal
- Department of Clinical Epidemiology, Leiden University Medical Center, Leiden, The Netherlands
| | - Vera Schrauwen-Hinderling
- Department of Human Biology, NUTRIM School for Nutrition and Translational Research in Metabolism, Maastricht University Medical Center, Maastricht, The Netherlands
- Department of Radiology, NUTRIM School for Nutrition and Translational Research in Metabolism, Maastricht University Medical Center, Maastricht, The Netherlands
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35
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Yamada A, Honma K, Mochizuki K, Goda T. BRD4 regulates fructose-inducible lipid accumulation-related genes in the mouse liver. Metabolism 2016; 65:1478-88. [PMID: 27621183 DOI: 10.1016/j.metabol.2016.07.001] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/21/2016] [Revised: 06/01/2016] [Accepted: 07/04/2016] [Indexed: 12/16/2022]
Abstract
OBJECTIVE Fructose intake induces hepatic steatosis by activating fat synthesis. In this study, we searched for genes that showed acute induction in the livers of mice force-fed with fructose, and examined how this induction is regulated. MATERIALS/METHODS We identified genes induced at 6h after the fructose force-feeding using a microarray and quantitative real-time RT-PCR. Histone acetylation and an acetylated histone binding protein bromodomain containing (BRD)4 binding around the fructose-inducible genes were examined using a chromatin immunoprecipitation assay. We examined whether (+)-JQ1, an inhibitor of the binding between the BRD4 and acetylated histones, inhibited the expressions of fructose-inducible genes, histone acetylation and BRD4 binding around the genes. RESULTS We identified upregulated genes related to lipid accumulation, such as Cyp8b1, Dak and Plin5, in mice force-fed with fructose compared with those force-fed with glucose. Acetylation of histones H3 and H4, and BRD4 binding around the transcribed region of those fructose-inducible genes, were enhanced by fructose force-feeding. Meanwhile, (+)-JQ1 treatment reduced expressions of fructose-inducible genes, histone acetylation and BRD4 binding around these genes. CONCLUSIONS Acute induction of genes related to lipid accumulation in the livers of mice force-fed with fructose is associated with the induction of histone acetylation and BRD4 binding around these genes.
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Affiliation(s)
- Aki Yamada
- Laboratory of Nutritional Physiology, Graduate School of Nutritional and Environmental Sciences, Laboratory of Nutritional Physiology, University of Shizuoka, Shizuoka, Japan
| | - Kazue Honma
- Laboratory of Nutritional Physiology, Graduate School of Nutritional and Environmental Sciences, Laboratory of Nutritional Physiology, University of Shizuoka, Shizuoka, Japan
| | - Kazuki Mochizuki
- Laboratory of Food and Nutritional Sciences, Department of Local Produce and Food Sciences, Faculty of Life and Environmental Sciences, University of Yamanashi, Yamanashi, Japan
| | - Toshinao Goda
- Laboratory of Nutritional Physiology, Graduate School of Nutritional and Environmental Sciences, Laboratory of Nutritional Physiology, University of Shizuoka, Shizuoka, Japan.
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36
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Gallardo-Montejano VI, Saxena G, Kusminski CM, Yang C, McAfee JL, Hahner L, Hoch K, Dubinsky W, Narkar VA, Bickel PE. Nuclear Perilipin 5 integrates lipid droplet lipolysis with PGC-1α/SIRT1-dependent transcriptional regulation of mitochondrial function. Nat Commun 2016; 7:12723. [PMID: 27554864 PMCID: PMC4999519 DOI: 10.1038/ncomms12723] [Citation(s) in RCA: 102] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2015] [Accepted: 07/27/2016] [Indexed: 12/18/2022] Open
Abstract
Dysfunctional cellular lipid metabolism contributes to common chronic human diseases, including type 2 diabetes, obesity, fatty liver disease and diabetic cardiomyopathy. How cells balance lipid storage and mitochondrial oxidative capacity is poorly understood. Here we identify the lipid droplet protein Perilipin 5 as a catecholamine-triggered interaction partner of PGC-1α. We report that during catecholamine-stimulated lipolysis, Perilipin 5 is phosphorylated by protein kinase A and forms transcriptional complexes with PGC-1α and SIRT1 in the nucleus. Perilipin 5 promotes PGC-1α co-activator function by disinhibiting SIRT1 deacetylase activity. We show by gain-and-loss of function studies in cells that nuclear Perilipin 5 promotes transcription of genes that mediate mitochondrial biogenesis and oxidative function. We propose that Perilipin 5 is an important molecular link that couples the coordinated catecholamine activation of the PKA pathway and of lipid droplet lipolysis with transcriptional regulation to promote efficient fatty acid catabolism and prevent mitochondrial dysfunction.
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Affiliation(s)
- Violeta I. Gallardo-Montejano
- Division of Endocrinology, Department of Internal Medicine, The University of Texas Southwestern Medical Center, Dallas, Texas 75390, USA
| | - Geetu Saxena
- Center for Metabolic and Degenerative Diseases, The Brown Foundation Institute of Molecular Medicine for The Prevention Of Human Diseases, UT Health, Houston, Texas 77030, USA
| | - Christine M. Kusminski
- Touchstone Diabetes Center, Department of Internal Medicine, The University of Texas Southwestern Medical Center, Dallas, Texas 75390, USA
| | - Chaofeng Yang
- Division of Endocrinology, Department of Internal Medicine, The University of Texas Southwestern Medical Center, Dallas, Texas 75390, USA
| | - John L. McAfee
- Division of Endocrinology, Department of Internal Medicine, The University of Texas Southwestern Medical Center, Dallas, Texas 75390, USA
| | - Lisa Hahner
- Division of Endocrinology, Department of Internal Medicine, The University of Texas Southwestern Medical Center, Dallas, Texas 75390, USA
| | - Kathleen Hoch
- Center for Metabolic and Degenerative Diseases, The Brown Foundation Institute of Molecular Medicine for The Prevention Of Human Diseases, UT Health, Houston, Texas 77030, USA
| | - William Dubinsky
- Center for Metabolic and Degenerative Diseases, The Brown Foundation Institute of Molecular Medicine for The Prevention Of Human Diseases, UT Health, Houston, Texas 77030, USA
| | - Vihang A. Narkar
- Center for Metabolic and Degenerative Diseases, The Brown Foundation Institute of Molecular Medicine for The Prevention Of Human Diseases, UT Health, Houston, Texas 77030, USA
| | - Perry E. Bickel
- Division of Endocrinology, Department of Internal Medicine, The University of Texas Southwestern Medical Center, Dallas, Texas 75390, USA
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Johns M, Esmaeili Mohsen Abadi S, Malik N, Lee J, Neumann WL, Rausaria S, Imani-Nejad M, McPherson T, Schober J, Kwon G. Oral administration of SR-110, a peroxynitrite decomposing catalyst, enhances glucose homeostasis, insulin signaling, and islet architecture in B6D2F1 mice fed a high fat diet. Arch Biochem Biophys 2016; 596:126-37. [PMID: 26970045 DOI: 10.1016/j.abb.2016.03.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2015] [Revised: 02/23/2016] [Accepted: 03/02/2016] [Indexed: 01/03/2023]
Abstract
Peroxynitrite has been implicated in type 2 diabetes and diabetic complications. As a follow-up study to our previous work on SR-135 (Arch Biochem Biophys 577-578: 49-59, 2015), we provide evidence that this series of compounds are effective when administered orally, and their mechanisms of actions extend to the peripheral tissues. A more soluble analogue of SR-135, SR-110 (from a new class of Mn(III) bis(hydroxyphenyl)-dipyrromethene complexes) was orally administered for 2 weeks to B6D2F1 mice fed a high fat-diet (HFD). Mice fed a HFD for 4 months gained significantly higher body weights compared to lean diet-fed mice (52 ± 1.5 g vs 34 ± 1.3 g). SR-110 (10 mg/kg daily) treatment significantly reduced fasting blood glucose and insulin levels, and enhanced glucose tolerance as compared to HFD control or vehicle (peanut butter) group. SR-110 treatment enhanced insulin signaling in the peripheral organs, liver, heart, and skeletal muscle, and reduced lipid accumulation in the liver. Furthermore, SR-110 increased insulin content, restored islet architecture, decreased islet size, and reduced tyrosine nitration. These results suggest that a peroxynitrite decomposing catalyst is effective in improving glucose homeostasis and restoring islet morphology and β-cell insulin content under nutrient overload.
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Affiliation(s)
- Michael Johns
- Department of Biological Sciences, Southern Illinois University Edwardsville, Edwardsville, IL, 62026, USA
| | | | - Nehal Malik
- Department of Biological Sciences, Southern Illinois University Edwardsville, Edwardsville, IL, 62026, USA
| | - Joshua Lee
- School of Pharmacy, Southern Illinois University Edwardsville, Edwardsville, IL, 62026, USA
| | - William L Neumann
- School of Pharmacy, Southern Illinois University Edwardsville, Edwardsville, IL, 62026, USA
| | - Smita Rausaria
- School of Pharmacy, Southern Illinois University Edwardsville, Edwardsville, IL, 62026, USA
| | - Maryam Imani-Nejad
- School of Pharmacy, Southern Illinois University Edwardsville, Edwardsville, IL, 62026, USA
| | - Timothy McPherson
- School of Pharmacy, Southern Illinois University Edwardsville, Edwardsville, IL, 62026, USA
| | - Joseph Schober
- School of Pharmacy, Southern Illinois University Edwardsville, Edwardsville, IL, 62026, USA
| | - Guim Kwon
- School of Pharmacy, Southern Illinois University Edwardsville, Edwardsville, IL, 62026, USA.
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