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Vinik Y, Maimon A, Dubey V, Raj H, Abramovitch I, Malitsky S, Itkin M, Ma'ayan A, Westermann F, Gottlieb E, Ruppin E, Lev S. Programming a Ferroptosis-to-Apoptosis Transition Landscape Revealed Ferroptosis Biomarkers and Repressors for Cancer Therapy. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2024; 11:e2307263. [PMID: 38441406 PMCID: PMC11077643 DOI: 10.1002/advs.202307263] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/05/2023] [Revised: 02/11/2024] [Indexed: 05/09/2024]
Abstract
Ferroptosis and apoptosis are key cell-death pathways implicated in several human diseases including cancer. Ferroptosis is driven by iron-dependent lipid peroxidation and currently has no characteristic biomarkers or gene signatures. Here a continuous phenotypic gradient between ferroptosis and apoptosis coupled to transcriptomic and metabolomic landscapes is established. The gradual ferroptosis-to-apoptosis transcriptomic landscape is used to generate a unique, unbiased transcriptomic predictor, the Gradient Gene Set (GGS), which classified ferroptosis and apoptosis with high accuracy. Further GGS optimization using multiple ferroptotic and apoptotic datasets revealed highly specific ferroptosis biomarkers, which are robustly validated in vitro and in vivo. A subset of the GGS is associated with poor prognosis in breast cancer patients and PDXs and contains different ferroptosis repressors. Depletion of one representative, PDGFA-assaociated protein 1(PDAP1), is found to suppress basal-like breast tumor growth in a mouse model. Omics and mechanistic studies revealed that ferroptosis is associated with enhanced lysosomal function, glutaminolysis, and the tricarboxylic acid (TCA) cycle, while its transition into apoptosis is attributed to enhanced endoplasmic reticulum(ER)-stress and phosphatidylethanolamine (PE)-to-phosphatidylcholine (PC) metabolic shift. Collectively, this study highlights molecular mechanisms underlying ferroptosis execution, identified a highly predictive ferroptosis gene signature with prognostic value, ferroptosis versus apoptosis biomarkers, and ferroptosis repressors for breast cancer therapy.
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Affiliation(s)
- Yaron Vinik
- Molecular Cell Biology DepartmentWeizmann Institute of ScienceRehovot76100Israel
| | - Avi Maimon
- Molecular Cell Biology DepartmentWeizmann Institute of ScienceRehovot76100Israel
| | - Vinay Dubey
- Molecular Cell Biology DepartmentWeizmann Institute of ScienceRehovot76100Israel
| | - Harsha Raj
- Molecular Cell Biology DepartmentWeizmann Institute of ScienceRehovot76100Israel
| | - Ifat Abramovitch
- The Ruth and Bruce RappaportFaculty of MedicineTechnion–Israel Institute of TechnologyHaifa3525433Israel
| | - Sergey Malitsky
- Metabolic Profiling UnitWeizmann Institute of ScienceRehovot76100Israel
| | - Maxim Itkin
- Metabolic Profiling UnitWeizmann Institute of ScienceRehovot76100Israel
| | - Avi Ma'ayan
- Department of Pharmacological SciencesMount Sinai Center for BioinformaticsIcahn School of Medicine at Mount SinaiNew YorkNY10029USA
| | - Frank Westermann
- Neuroblastoma GenomicsGerman Cancer Research Center (DKFZ)69120HeidelbergGermany
| | - Eyal Gottlieb
- The Ruth and Bruce RappaportFaculty of MedicineTechnion–Israel Institute of TechnologyHaifa3525433Israel
| | - Eytan Ruppin
- Cancer Data Science LaboratoryNational Cancer InstituteNational Institutes of HealthBethesdaMD20892USA
| | - Sima Lev
- Molecular Cell Biology DepartmentWeizmann Institute of ScienceRehovot76100Israel
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Ajoolabady A, Kaplowitz N, Lebeaupin C, Kroemer G, Kaufman RJ, Malhi H, Ren J. Endoplasmic reticulum stress in liver diseases. Hepatology 2023; 77:619-639. [PMID: 35524448 PMCID: PMC9637239 DOI: 10.1002/hep.32562] [Citation(s) in RCA: 79] [Impact Index Per Article: 79.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Revised: 03/05/2022] [Accepted: 03/08/2022] [Indexed: 02/02/2023]
Abstract
The endoplasmic reticulum (ER) is an intracellular organelle that fosters the correct folding of linear polypeptides and proteins, a process tightly governed by the ER-resident enzymes and chaperones. Failure to shape the proper 3-dimensional architecture of proteins culminates in the accumulation of misfolded or unfolded proteins within the ER, disturbs ER homeostasis, and leads to canonically defined ER stress. Recent studies have elucidated that cellular perturbations, such as lipotoxicity, can also lead to ER stress. In response to ER stress, the unfolded protein response (UPR) is activated to reestablish ER homeostasis ("adaptive UPR"), or, conversely, to provoke cell death when ER stress is overwhelmed and sustained ("maladaptive UPR"). It is well documented that ER stress contributes to the onset and progression of multiple hepatic pathologies including NAFLD, alcohol-associated liver disease, viral hepatitis, liver ischemia, drug toxicity, and liver cancers. Here, we review key studies dealing with the emerging role of ER stress and the UPR in the pathophysiology of liver diseases from cellular, murine, and human models. Specifically, we will summarize current available knowledge on pharmacological and non-pharmacological interventions that may be used to target maladaptive UPR for the treatment of nonmalignant liver diseases.
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Affiliation(s)
- Amir Ajoolabady
- Department of Cardiology, Shanghai Institute for Cardiovascular Diseases, Zhongshan Hospital Fudan University, Shanghai, China
| | - Neil Kaplowitz
- Division of Gastrointestinal and Liver Disease, Department of Medicine, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA
- USC Research Center for Liver Disease, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA
| | - Cynthia Lebeaupin
- Degenerative Diseases Program, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA 92037, USA
| | - Guido Kroemer
- Centre de Recherche des Cordeliers, Equipe labellisée par la Ligue contre le cancer, Université de Paris, Sorbonne Université, Inserm U1138, Institut Universitaire de France, Paris, France
- Metabolomics and Cell Biology Platforms, Institut Gustave Roussy, Villejuif, France
- Pôle de Biologie, Hôpital Européen Georges Pompidou, AP-HP, Paris, France
| | - Randal J. Kaufman
- Degenerative Diseases Program, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA 92037, USA
| | - Harmeet Malhi
- Division of Gastroenterology and Hepatology, Mayo Clinic, Rochester, MN 55905, USA
| | - Jun Ren
- Department of Cardiology, Shanghai Institute for Cardiovascular Diseases, Zhongshan Hospital Fudan University, Shanghai, China
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, WA 98195, USA
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Kunicka Z, Mierzejewski K, Kurzyńska A, Stryiński R, Mateos J, Carrera M, Golubska M, Bogacka I. Analysis of changes in the proteomic profile of porcine corpus luteum during different stages of the oestrous cycle: effects of PPAR gamma ligands. Reprod Fertil Dev 2022; 34:776-788. [PMID: 35577556 DOI: 10.1071/rd21248] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Accepted: 04/12/2022] [Indexed: 01/05/2023] Open
Abstract
CONTEXT The corpus luteum (CL) is an endocrine gland in the ovary of mature females during the oestrous cycle and pregnancy. There is evidence of a relationship between the secretory function of the CL and PPARs. AIMS In this study, we investigated the changes in the proteome of the CL in relation to the phase of the oestrous cycle and the impact of PPARγ ligands on the proteomic profile of the CL during the mid- and late-luteal phase of the oestrous cycle. METHODS The porcine CL explants were incubated in vitro for 6h in the presence of PPARγ ligands (agonist pioglitazone, antagonist T0070907) or without ligands. Global proteomic analysis was performed using the TMT-based LC-MS/MS method. KEY RESULTS The obtained results showed the disparity in proteomic profile of the untreated CL - different abundance of 23 and 28 proteins for the mid- and late-luteal phase, respectively. Moreover, seven proteins were differentially regulated in the CL tissue treated with PPARγ ligands. In the mid-luteal phase, one protein, CAND1, was downregulated after treatment with T0070907. In the late-luteal phase, the proteins SPTAN1, GOLGB1, TP53BP1, MATR3, RRBP1 and SRRT were upregulated by pioglitazone. CONCLUSIONS Comparative proteomic analysis revealed that certain proteins constitute a specific proteomic signature for each examined phase. Moreover, the study showed that the effect of PPARγ ligands on the CL proteome was rather limited. IMPLICATIONS The results provide a broader insight into the processes that may be responsible for the structural luteolysis of the porcine CL, in addition to apoptosis and autophagy.
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Affiliation(s)
- Zuzanna Kunicka
- Department of Animal Anatomy and Physiology, Faculty of Biology and Biotechnology, University of Warmia and Mazury in Olsztyn, 10-719 Olsztyn, Poland
| | - Karol Mierzejewski
- Department of Animal Anatomy and Physiology, Faculty of Biology and Biotechnology, University of Warmia and Mazury in Olsztyn, 10-719 Olsztyn, Poland
| | - Aleksandra Kurzyńska
- Department of Animal Anatomy and Physiology, Faculty of Biology and Biotechnology, University of Warmia and Mazury in Olsztyn, 10-719 Olsztyn, Poland
| | - Robert Stryiński
- Department of Biochemistry, Faculty of Biology and Biotechnology, University of Warmia and Mazury in Olsztyn, 10-719 Olsztyn, Poland
| | - Jesús Mateos
- Galapagos NV, Generaal de Wittelaan L11, 2800 Mechelen, Belgium
| | - Mónica Carrera
- Department of Food Technology, Marine Research Institute (IIM), Spanish National Research Council (CSIC), 36208 Vigo, Spain
| | - Monika Golubska
- Department of Animal Anatomy and Physiology, Faculty of Biology and Biotechnology, University of Warmia and Mazury in Olsztyn, 10-719 Olsztyn, Poland
| | - Iwona Bogacka
- Department of Animal Anatomy and Physiology, Faculty of Biology and Biotechnology, University of Warmia and Mazury in Olsztyn, 10-719 Olsztyn, Poland
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Prasad M K, Mohandas S, Ramkumar KM. Role of ER stress inhibitors in the management of diabetes. Eur J Pharmacol 2022; 922:174893. [DOI: 10.1016/j.ejphar.2022.174893] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2022] [Revised: 03/07/2022] [Accepted: 03/09/2022] [Indexed: 12/14/2022]
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Ma J, Zeng P, Liu L, Zhu M, Zheng J, Wang C, Zhao X, Hu W, Yang X, Duan Y, Han J, Miao QR, Chen Y. Peroxisome Proliferator-Activated Receptor-Gamma Reduces ER Stress and Inflammation via Targeting NGBR Expression. Front Pharmacol 2022; 12:817784. [PMID: 35111067 PMCID: PMC8801792 DOI: 10.3389/fphar.2021.817784] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2021] [Accepted: 12/27/2021] [Indexed: 01/01/2023] Open
Abstract
Increased Nogo-B receptor (NGBR) expression in the liver improves insulin sensitivity by reducing endoplasmic reticulum stress (ER stress) and activating the AMPK pathway, although it remains elusive the mechanisms by which NGBR is induced. In this study, we found that PPARγ ligands (rosiglitazone or pioglitazone) increased NGBR expression in hepatic cells and HUVECs. Furthermore, promoter analysis defined two PPREs (PPARγ-responsive elements) in the promoter region of NGBR, which was further confirmed by the ChIP assay. In vivo, using liver-specific PPARγ deficient (PPARγLKO) mice, we identified the key role of PPARγ expression in pioglitazone-induced NGBR expression. Meanwhile, the basal level of ER stress and inflammation was slightly increased by NGBR knockdown. However, the inhibitory effect of rosiglitazone on inflammation was abolished while rosiglitazone-inhibited ER stress was weakened by NGBR knockdown. Taken together, these findings show that NGBR is a previously unrecognized target of PPARγ activation and plays an essential role in PPARγ-reduced ER stress and inflammation.
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Affiliation(s)
- Jialing Ma
- Key Laboratory of Major Metabolic Diseases and Nutritional Regulation of Anhui Department of Education, College of Food and Biological Engineering, Hefei University of Technology, Hefei, China
| | - Peng Zeng
- College of Life Sciences, State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Bioactive Materials of Ministry of Education, Nankai University, Tianjin, China
| | - Lipei Liu
- College of Life Sciences, State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Bioactive Materials of Ministry of Education, Nankai University, Tianjin, China
| | - Mengmeng Zhu
- Key Laboratory of Major Metabolic Diseases and Nutritional Regulation of Anhui Department of Education, College of Food and Biological Engineering, Hefei University of Technology, Hefei, China
| | - Juan Zheng
- Key Laboratory of Major Metabolic Diseases and Nutritional Regulation of Anhui Department of Education, College of Food and Biological Engineering, Hefei University of Technology, Hefei, China
| | - Chengyi Wang
- Key Laboratory of Major Metabolic Diseases and Nutritional Regulation of Anhui Department of Education, College of Food and Biological Engineering, Hefei University of Technology, Hefei, China
| | - Xiaokang Zhao
- Key Laboratory of Major Metabolic Diseases and Nutritional Regulation of Anhui Department of Education, College of Food and Biological Engineering, Hefei University of Technology, Hefei, China
| | - Wenquan Hu
- Centre for Lipid Research & Key Laboratory of Molecular Biology for Infectious Diseases (Ministry of Education), Chongqing Medical University, Chongqing, China
| | - Xiaoxiao Yang
- Key Laboratory of Major Metabolic Diseases and Nutritional Regulation of Anhui Department of Education, College of Food and Biological Engineering, Hefei University of Technology, Hefei, China
| | - Yajun Duan
- Key Laboratory of Major Metabolic Diseases and Nutritional Regulation of Anhui Department of Education, College of Food and Biological Engineering, Hefei University of Technology, Hefei, China
| | - Jihong Han
- Key Laboratory of Major Metabolic Diseases and Nutritional Regulation of Anhui Department of Education, College of Food and Biological Engineering, Hefei University of Technology, Hefei, China.,College of Life Sciences, State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Bioactive Materials of Ministry of Education, Nankai University, Tianjin, China
| | - Qing R Miao
- Diabetes and Obesity Research Center, New York University Long Island School of Medicine, New York, NY, United States
| | - Yuanli Chen
- Key Laboratory of Major Metabolic Diseases and Nutritional Regulation of Anhui Department of Education, College of Food and Biological Engineering, Hefei University of Technology, Hefei, China
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Park CY, Lee SK, Kim J, Kim D, Choe H, Jeong JH, Choi KC, Park HS, Han SN, Jang YJ. Endoplasmic reticulum stress increases LECT2 expression via ATF4. Biochem Biophys Res Commun 2021; 585:169-176. [PMID: 34808500 DOI: 10.1016/j.bbrc.2021.11.038] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Accepted: 11/11/2021] [Indexed: 12/23/2022]
Abstract
Non-alcoholic fatty liver disease (NAFLD) is frequently associated with obesity, insulin resistance, and endoplasmic reticulum (ER) stress. Elevated circulating levels of the hepatokine leukocyte cell-derived chemotaxin-2 (LECT2) have also been noted in NAFLD; however, the mechanism underlying this association is unclear. To investigate a possible link between ER stress/unfolded protein response (UPR) signaling and LECT2 secretion, HepG2 cells were incubated with ER stress inducers with or without an ER stress-reducing chemical chaperone. Additionally, UPR pathway genes were knocked down and overexpressed, and a ChIP assay was performed. In diet-induced obese mice, hepatic expression of LECT2 and activating transcription factor 4 (ATF4) was measured. In HepG2 cells, LECT2 expression was increased by ER stressors, an effect blocked by the chemical chaperone. Among UPR pathway proteins, only knockdown of ATF4 suppressed ER stress-induced LECT2 expression, while overexpression of ATF4 enhanced LECT2 expression. The ChIP assay revealed that ATF4 binds to three putative binding sites on the LECT2 promoter and binding is promoted by an ER stress inducer. In steatotic livers of obese mice, LECT2 and ATF4 expression was concomitantly elevated. Our data indicate that activation of ER stress/UPR signaling induces LECT2 expression in steatotic liver; specifically, ATF4 appears to mediate upregulation of LECT2 transcription.
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Affiliation(s)
- Chan Yoon Park
- Department of Physiology, University of Ulsan College of Medicine, Seoul, South Korea; Department of Food & Nutrition, College of Health Science, The University of Suwon, Hwaseong-si, Gyeonggi-do, South Korea
| | - Seul Ki Lee
- Department of Physiology, University of Ulsan College of Medicine, Seoul, South Korea
| | - Jimin Kim
- Department of Physiology, University of Ulsan College of Medicine, Seoul, South Korea
| | - Donguk Kim
- Department of Physiology, University of Ulsan College of Medicine, Seoul, South Korea
| | - Han Choe
- Department of Physiology, University of Ulsan College of Medicine, Seoul, South Korea
| | - Ji-Hoon Jeong
- Department of Biomedical Sciences, Asan Medical Center, AMIST, University of Ulsan College of Medicine, Seoul, South Korea
| | - Kyung-Chul Choi
- Department of Biomedical Sciences, Asan Medical Center, AMIST, University of Ulsan College of Medicine, Seoul, South Korea
| | - Hye Soon Park
- Department of Family Medicine, University of Ulsan College of Medicine, Seoul, South Korea
| | - Sung Nim Han
- Department of Food and Nutrition & Research Institute of Human Ecology, College of Human Ecology, Seoul National University, Seoul, South Korea
| | - Yeon Jin Jang
- Department of Physiology, University of Ulsan College of Medicine, Seoul, South Korea.
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Lee JH, Han JH, Joe EH, Jou I. Small heterodimer partner (SHP) aggravates ER stress in Parkinson's disease-linked LRRK2 mutant astrocyte by regulating XBP1 SUMOylation. J Biomed Sci 2021; 28:51. [PMID: 34229656 PMCID: PMC8261914 DOI: 10.1186/s12929-021-00747-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Accepted: 06/13/2021] [Indexed: 12/15/2022] Open
Abstract
Background Endoplasmic reticulum (ER) stress is a common feature of Parkinson’s disease (PD), and several PD-related genes are responsible for ER dysfunction. Recent studies suggested LRRK2-G2019S, a pathogenic mutation in the PD-associated gene LRRK2, cause ER dysfunction, and could thereby contribute to the development of PD. It remains unclear, however, how mutant LRRK2 influence ER stress to control cellular outcome. In this study, we identified the mechanism by which LRRK2-G2019S accelerates ER stress and cell death in astrocytes. Methods To investigate changes in ER stress response genes, we treated LRRK2-wild type and LRRK2-G2019S astrocytes with tunicamycin, an ER stress-inducing agent, and performed gene expression profiling with microarrays. The XBP1 SUMOylation and PIAS1 ubiquitination were performed using immunoprecipitation assay. The effect of astrocyte to neuronal survival were assessed by astrocytes-neuron coculture and slice culture systems. To provide in vivo proof-of-concept of our approach, we measured ER stress response in mouse brain. Results Microarray gene expression profiling revealed that LRRK2-G2019S decreased signaling through XBP1, a key transcription factor of the ER stress response, while increasing the apoptotic ER stress response typified by PERK signaling. In LRRK2-G2019S astrocytes, the transcriptional activity of XBP1 was decreased by PIAS1-mediated SUMOylation. Intriguingly, LRRK2-GS stabilized PIAS1 by increasing the level of small heterodimer partner (SHP), a negative regulator of PIAS1 degradation, thereby promoting XBP1 SUMOylation. When SHP was depleted, XBP1 SUMOylation and cell death were reduced. In addition, we identified agents that can disrupt SHP-mediated XBP1 SUMOylation and may therefore have therapeutic activity in PD caused by the LRRK2-G2019S mutation. Conclusion Our findings reveal a novel regulatory mechanism involving XBP1 in LRRK2-G2019S mutant astrocytes, and highlight the importance of the SHP/PIAS1/XBP1 axis in PD models. These findings provide important insight into the basis of the correlation between mutant LRRK2 and pathophysiological ER stress in PD, and suggest a plausible model that explains this connection. Supplementary Information The online version contains supplementary material available at 10.1186/s12929-021-00747-1.
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Affiliation(s)
- Jee Hoon Lee
- Department of Pharmacology, Ajou University School of Medicine, Suwon, 442-721, South Korea.,Inflamm-Aging Translational Research Center, Ajou University School of Medicine, Suwon, South Korea
| | - Ji-Hye Han
- Department of Pharmacology, Ajou University School of Medicine, Suwon, 442-721, South Korea
| | - Eun-Hye Joe
- Department of Pharmacology, Ajou University School of Medicine, Suwon, 442-721, South Korea
| | - Ilo Jou
- Department of Pharmacology, Ajou University School of Medicine, Suwon, 442-721, South Korea. .,Inflamm-Aging Translational Research Center, Ajou University School of Medicine, Suwon, South Korea.
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Bruschi FV, Tardelli M, Herac M, Claudel T, Trauner M. Metabolic regulation of hepatic PNPLA3 expression and severity of liver fibrosis in patients with NASH. Liver Int 2020; 40:1098-1110. [PMID: 32043752 PMCID: PMC7318357 DOI: 10.1111/liv.14402] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/23/2019] [Revised: 01/31/2020] [Accepted: 02/03/2020] [Indexed: 02/06/2023]
Abstract
BACKGROUND AND AIMS The genetic PNPLA3 polymorphism I148M has been extensively associated with higher risk for development and progression of NAFLD towards NASH. METHODS PNPLA3 and α-SMA expression were quantified in liver biopsies collected from NASH patients (n = 26) with different fibrosis stages and PNPLA3 genotypes. To study the potential mechanisms driving PNPLA3 expression during NASH progression towards fibrosis, hepatocytes and hepatic stellate cells (HSCs) were cultivated in low and high glucose medium. Moreover, hepatocytes were treated with increasing concentrations of palmitic acid alone or in combination with glucose. Conditioned media were collected from challenged hepatocytes to stimulate HSCs. RESULTS Tissue expression of PNPLA3 was significantly enhanced in biopsies of patients carrying the I148M polymorphism compared to wild type (WT). In NASH biopsies, PNPLA3 significantly correlated with fibrosis stage and α-SMA levels independently of PNPLA3 genotype. In line, PNPLA3 expression was higher in α-SMA positive cells. Low glucose increased PNPLA3 in HSCs, whereas high glucose induced PNPLA3 and de-novo lipogenesis-related genes expression in hepatocytes. Palmitic acid induced fat accumulation and cell stress markers in hepatocytes, which could be counteracted by oleic acid. Conditioned media collected from lipotoxic challenged hepatocytes markedly induced PNPLA3 mRNA and protein levels, fibrogenic and autophagic markers and promoted migration in HSCs. Notably, conditioned media collected from hepatocytes cultivated with both glucose and palmitic acid exacerbated HSCs migration, PNPLA3 and fibrogenic gene expression, promoting release of cytokines from HSCs. CONCLUSIONS Collectively, our observations uncover the diverse metabolic regulation of PNPLA3 among different hepatic cell populations and support its relation to fibrosis progression.
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Affiliation(s)
- Francesca V. Bruschi
- Hans Popper Laboratory of Molecular HepatologyDivision of Gastroenterology and HepatologyInternal Medicine IIIMedical University of ViennaViennaAustria
| | - Matteo Tardelli
- Hans Popper Laboratory of Molecular HepatologyDivision of Gastroenterology and HepatologyInternal Medicine IIIMedical University of ViennaViennaAustria,Division of Gastroenterology and HepatologyJoan and Sanford I. Weill Cornell Department of MedicineWeill Cornell Medical CollegeNew YorkNYUSA
| | - Merima Herac
- Clinical Institute of PathologyMedical University of ViennaViennaAustria
| | - Thierry Claudel
- Hans Popper Laboratory of Molecular HepatologyDivision of Gastroenterology and HepatologyInternal Medicine IIIMedical University of ViennaViennaAustria
| | - Michael Trauner
- Hans Popper Laboratory of Molecular HepatologyDivision of Gastroenterology and HepatologyInternal Medicine IIIMedical University of ViennaViennaAustria
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Zhu MK, Li HY, Bai LH, Wang LS, Zou XT. Histological changes, lipid metabolism, and oxidative and endoplasmic reticulum stress in the liver of laying hens exposed to cadmium concentrations. Poult Sci 2020; 99:3215-3228. [PMID: 32475458 PMCID: PMC7597684 DOI: 10.1016/j.psj.2019.12.073] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2019] [Revised: 10/21/2019] [Accepted: 12/24/2019] [Indexed: 12/18/2022] Open
Abstract
The objective of this study was to determine the effects of cadmium (Cd) on histological changes, lipid metabolism, and oxidative and endoplasmic reticulum (ER) stress in the liver of layers. A total of 480 hens at 38 wk of age were randomly assigned in 5 groups that were fed a basal diet or basal diet supplemented with CdCl2 2.5H2O at 7.5, 15, 30, and 60 mg Cd/kg feed for 9 wk. The results showed that accumulation of Cd was the greatest in the kidney, followed by the liver, pancreas, and lung. Diet contaminated with 30 mg Cd/kg induced antioxidant defenses accompanied by the increase of the activities of antioxidant enzymes in the liver, while dietary supplementation with 60 mg Cd/kg decreased the antioxidant levels significantly (P < 0.05). Immunofluorescence assay showed Cd induced reactive oxygen species production and endoplasmic reticulum stress in hepatocytes. Exposure to 60 mg Cd/kg significantly upregulated the expression of cytochrome C, caspase 3, caspase 9, caspase 7, Grp78, and Chop (P < 0.05). Histopathology and quantitative real-time PCR results presented periportal fibrosis, bile duct hyperplasia, and periportal inflammatory cell infiltration in the liver accompanied by upregulating the expression of tumor necrosis factor-α, IL-6 and IL-10 in the 30- or 60-mg Cd/kg groups. Oil Red O staining and RT-qPCR results showed dietary supplementation with 7.5, 15, and 30 mg Cd/kg promoted the synthesis of lipid droplets and upregulated the expression of fatty acid synthase, while dietary supplementation with 60 mg Cd/kg attenuated the synthesis of lipid droplets and downregulated the expression of acyl-CoA oxidase 1, carnitine palmitoyltransferase-1, and perixisome proliferation-activated receptor α (P < 0.05). Besides, the expression of vitellogenin (VTG) II and microsomal triglyceride transfer protein were upregulated in the 7.5-mg Cd/kg group, and the expressions of apolipoprotein B, vitellogenin II, and apolipoprotein very-low-density lipoprotein-II were downregulated in the 30- and/or 60-mg Cd/kg groups (P < 0.05). Conclusively, although low-dose Cd exposure promoted the synthesis of lipids and lipoproteins in the liver, the increase of Cd exposure could trigger liver injury through inducing oxidative and endoplasmic reticulum stress and negatively affect lipid metabolism and yolk formation in laying hens.
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Affiliation(s)
- M K Zhu
- Key Laboratory of Animal Feed and Nutrition of Zhejiang Province, Key Laboratory of Animal Nutrition and Feed Science in East China, Ministry of Agriculture, The Key Laboratory of Molecular Animal Nutrition, Ministry of Education, College of Animal Sciences, Zhejiang University, Hangzhou 310058, P.R. China
| | - H Y Li
- Key Laboratory of Animal Feed and Nutrition of Zhejiang Province, Key Laboratory of Animal Nutrition and Feed Science in East China, Ministry of Agriculture, The Key Laboratory of Molecular Animal Nutrition, Ministry of Education, College of Animal Sciences, Zhejiang University, Hangzhou 310058, P.R. China
| | - L H Bai
- Key Laboratory of Animal Feed and Nutrition of Zhejiang Province, Key Laboratory of Animal Nutrition and Feed Science in East China, Ministry of Agriculture, The Key Laboratory of Molecular Animal Nutrition, Ministry of Education, College of Animal Sciences, Zhejiang University, Hangzhou 310058, P.R. China
| | - L S Wang
- Jiande Weifeng Feed Co., Ltd., Jiande, 311603 Hangzhou, Zhejiang, P.R. China
| | - X T Zou
- Key Laboratory of Animal Feed and Nutrition of Zhejiang Province, Key Laboratory of Animal Nutrition and Feed Science in East China, Ministry of Agriculture, The Key Laboratory of Molecular Animal Nutrition, Ministry of Education, College of Animal Sciences, Zhejiang University, Hangzhou 310058, P.R. China.
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Xiao T, Liang X, Liu H, Zhang F, Meng W, Hu F. Mitochondrial stress protein HSP60 regulates ER stress-induced hepatic lipogenesis. J Mol Endocrinol 2020; 64:67-75. [PMID: 31804966 PMCID: PMC6993205 DOI: 10.1530/jme-19-0207] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/21/2019] [Accepted: 12/04/2019] [Indexed: 01/15/2023]
Abstract
Endoplasmic reticulum (ER) stress and mitochondrial dysfunction are associated with hepatic steatosis and insulin resistance. Molecular mechanisms underlying ER stress and/or mitochondrial dysfunction that cause metabolic disorders and hepatic steatosis remain to be fully understood. Here, we found that a high fat diet (HFD) or chemically induced ER stress can stimulate mitochondrial stress protein HSP60 expression, impair mitochondrial respiration, and decrease mitochondrial membrane potential in mouse hepatocytes. HSP60 overexpression promotes ER stress and hepatic lipogenic protein expression and impairs insulin signaling in mouse hepatocytes. Mechanistically, HSP60 regulates ER stress-induced hepatic lipogenesis via the mTORC1-SREBP1 signaling pathway. These results suggest that HSP60 is an important ER and mitochondrial stress cross-talking protein and may control ER stress-induced hepatic lipogenesis and insulin resistance.
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Affiliation(s)
- Ting Xiao
- Department of Metabolism and Endocrinology, The Second Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Xiuci Liang
- Department of Metabolism and Endocrinology, The Second Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Hailan Liu
- Department of Metabolism and Endocrinology, The Second Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Feng Zhang
- Department of Metabolism and Endocrinology, The Second Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Wen Meng
- Department of Metabolism and Endocrinology, The Second Xiangya Hospital, Central South University, Changsha, Hunan, China
- Correspondence should be addressed to F Hu: or to W Meng:
| | - Fang Hu
- Department of Metabolism and Endocrinology, The Second Xiangya Hospital, Central South University, Changsha, Hunan, China
- National Clinical Research Center for Metabolic Diseases, Changsha, Hunan, China
- Metabolic Syndrome Research Center, Central South University, Changsha, Hunan, China
- Correspondence should be addressed to F Hu: or to W Meng:
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11
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Soliman E, Behairy SF, El-maraghy NN, Elshazly SM. PPAR-γ agonist, pioglitazone, reduced oxidative and endoplasmic reticulum stress associated with L-NAME-induced hypertension in rats. Life Sci 2019; 239:117047. [DOI: 10.1016/j.lfs.2019.117047] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2019] [Revised: 10/30/2019] [Accepted: 11/02/2019] [Indexed: 02/07/2023]
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12
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Abstract
Endoplasmic reticulum (ER) stress is a major contributor to liver disease and hepatic fibrosis, but the role it plays varies depending on the cause and progression of the disease. Furthermore, ER stress plays a distinct role in hepatocytes versus hepatic stellate cells (HSCs), which adds to the complexity of understanding ER stress and its downstream signaling through the unfolded protein response (UPR) in liver disease. Here, the authors focus on the current literature of ER stress in nonalcoholic and alcoholic fatty liver diseases, how ER stress impacts hepatocyte injury, and the role of ER stress in HSC activation and hepatic fibrosis. This review provides insight into the complex signaling and regulation of the UPR, parallels and distinctions between different liver diseases, and how ER stress may be targeted as an antisteatotic or antifibrotic therapy to limit the progression of liver disease.
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Affiliation(s)
- Jessica L. Maiers
- Division of Gastroenterology and Hepatology, Mayo Clinic, Rochester, Minnesota
| | - Harmeet Malhi
- Division of Gastroenterology and Hepatology, Mayo Clinic, Rochester, Minnesota
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13
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Rosiglitazone rescues human neural stem cells from amyloid-beta induced ER stress via PPARγ dependent signaling. Exp Cell Res 2018; 370:312-321. [DOI: 10.1016/j.yexcr.2018.06.033] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2018] [Revised: 06/23/2018] [Accepted: 06/27/2018] [Indexed: 12/15/2022]
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14
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Kalavalapalli S, Bril F, Koelmel JP, Abdo K, Guingab J, Andrews P, Li WY, Jose D, Yost RA, Frye RF, Garrett TJ, Cusi K, Sunny NE. Pioglitazone improves hepatic mitochondrial function in a mouse model of nonalcoholic steatohepatitis. Am J Physiol Endocrinol Metab 2018; 315:E163-E173. [PMID: 29634314 PMCID: PMC6139494 DOI: 10.1152/ajpendo.00023.2018] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Pioglitazone is effective in improving insulin resistance and liver histology in patients with nonalcoholic steatohepatitis (NASH). Because dysfunctional mitochondrial metabolism is a central feature of NASH, we hypothesized that an important target of pioglitazone would be alleviating mitochondrial oxidative dysfunction. To this end, we studied hepatic mitochondrial metabolism in mice fed high-fructose high-transfat diet (TFD) supplemented with pioglitazone for 20 wk, using nuclear magnetic resonance-based 13C isotopomer analysis. Pioglitazone improved whole body and adipose insulin sensitivity in TFD-fed mice. Furthermore, pioglitazone reduced intrahepatic triglyceride content and fed plasma ketones and hepatic TCA cycle flux, anaplerosis, and pyruvate cycling in mice with NASH. This was associated with a marked reduction in most intrahepatic diacylglycerol classes and, to a lesser extent, some ceramide species (C22:1, C23:0). Considering the cross-talk between mitochondrial function and branched-chain amino acid (BCAA) metabolism, pioglitazone's impact on plasma BCAA profile was determined in a cohort of human subjects. Pioglitazone improved the plasma BCAA concentration profile in patients with NASH. This appeared to be related to an improvement in BCAA degradation in multiple tissues. These results provide evidence that pioglitazone-induced changes in NASH are related to improvements in hepatic mitochondrial oxidative dysfunction and changes in whole body BCAA metabolism.
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Affiliation(s)
- Srilaxmi Kalavalapalli
- Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, University of Florida , Gainesville, Florida
| | - Fernando Bril
- Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, University of Florida , Gainesville, Florida
| | - Jeremy P Koelmel
- Department of Chemistry, University of Florida , Gainesville, Florida
| | - Kaitlyn Abdo
- Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, University of Florida , Gainesville, Florida
| | - Joy Guingab
- Department of Pathology, University of Florida , Gainesville, Florida
| | - Paige Andrews
- Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, University of Florida , Gainesville, Florida
| | - Wen-Yi Li
- Department of Pharmacotherapy and Translational Research, College of Pharmacy, University of Florida , Gainesville, Florida
| | - Dhanya Jose
- Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, University of Florida , Gainesville, Florida
| | - Richard A Yost
- Department of Chemistry, University of Florida , Gainesville, Florida
- Department of Pathology, University of Florida , Gainesville, Florida
| | - Reginald F Frye
- Department of Pharmacotherapy and Translational Research, College of Pharmacy, University of Florida , Gainesville, Florida
| | - Timothy J Garrett
- Department of Pathology, University of Florida , Gainesville, Florida
| | - Kenneth Cusi
- Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, University of Florida , Gainesville, Florida
- Division of Endocrinology, Diabetes and Metabolism, Malcom Randall Veterans Administration Medical Center , Gainesville, Florida
| | - Nishanth E Sunny
- Department of Animal and Avian Sciences, University of Maryland , College Park, Maryland
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15
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Luo L, Jiang W, Liu H, Bu J, Tang P, Du C, Xu Z, Luo H, Liu B, Xiao B, Zhou Z, Liu F. De-silencing Grb10 contributes to acute ER stress-induced steatosis in mouse liver. J Mol Endocrinol 2018; 60:285-297. [PMID: 29555819 DOI: 10.1530/jme-18-0018] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/20/2018] [Accepted: 03/19/2018] [Indexed: 12/14/2022]
Abstract
The growth factor receptor bound protein GRB10 is an imprinted gene product and a key negative regulator of the insulin, IGF1 and mTORC1 signaling pathways. GRB10 is highly expressed in mouse fetal liver but almost completely silenced in adult mice, suggesting a potential detrimental role of this protein in adult liver function. Here we show that the Grb10 gene could be reactivated in adult mouse liver by acute endoplasmic reticulum stress (ER stress) such as tunicamycin or a short-term high-fat diet (HFD) challenge, concurrently with increased unfolded protein response (UPR) and hepatosteatosis. Lipogenic gene expression and acute ER stress-induced hepatosteatosis were significantly suppressed in the liver of the liver-specific GRB10 knockout mice, uncovering a key role of Grb10 reactivation in acute ER stress-induced hepatic lipid dysregulation. Mechanically, acute ER stress induces Grb10 reactivation via an ATF4-mediated increase in Grb10 gene transcription. Our study demonstrates for the first time that the silenced Grb10 gene can be reactivated by acute ER stress and its reactivation plays an important role in the early development of hepatic steatosis.
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Affiliation(s)
- Liping Luo
- Department of Metabolism and Endocrinology and the Metabolic Syndrome Research Center of Central South UniversityThe Second Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Wanxiang Jiang
- Department of Metabolism and Endocrinology and the Metabolic Syndrome Research Center of Central South UniversityThe Second Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Hui Liu
- Department of Metabolism and Endocrinology and the Metabolic Syndrome Research Center of Central South UniversityThe Second Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Jicheng Bu
- Department of Metabolism and Endocrinology and the Metabolic Syndrome Research Center of Central South UniversityThe Second Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Ping Tang
- The State Key Laboratory of BiotherapyWest China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Chongyangzi Du
- The State Key Laboratory of BiotherapyWest China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Zhipeng Xu
- Department of Metabolism and Endocrinology and the Metabolic Syndrome Research Center of Central South UniversityThe Second Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Hairong Luo
- Department of Metabolism and Endocrinology and the Metabolic Syndrome Research Center of Central South UniversityThe Second Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Bilian Liu
- Department of Metabolism and Endocrinology and the Metabolic Syndrome Research Center of Central South UniversityThe Second Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Bo Xiao
- Department of Metabolism and Endocrinology and the Metabolic Syndrome Research Center of Central South UniversityThe Second Xiangya Hospital, Central South University, Changsha, Hunan, China
- The State Key Laboratory of BiotherapyWest China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Zhiguang Zhou
- Department of Metabolism and Endocrinology and the Metabolic Syndrome Research Center of Central South UniversityThe Second Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Feng Liu
- Department of Metabolism and Endocrinology and the Metabolic Syndrome Research Center of Central South UniversityThe Second Xiangya Hospital, Central South University, Changsha, Hunan, China
- Department of PharmacologyUniversity of Texas Health Science Center at San Antonio, San Antonio, Texas, USA
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16
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Torre‐Villalvazo I, Bunt AE, Alemán G, Marquez‐Mota CC, Diaz‐Villaseñor A, Noriega LG, Estrada I, Figueroa‐Juárez E, Tovar‐Palacio C, Rodriguez‐López LA, López‐Romero P, Torres N, Tovar AR. Adiponectin synthesis and secretion by subcutaneous adipose tissue is impaired during obesity by endoplasmic reticulum stress. J Cell Biochem 2018; 119:5970-5984. [DOI: 10.1002/jcb.26794] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2017] [Accepted: 02/16/2018] [Indexed: 12/18/2022]
Affiliation(s)
- Ivan Torre‐Villalvazo
- Departamento de Fisiología de la NutriciónInstituto Nacional de Ciencias Médicas y Nutrición Salvador ZubiránMéxico CityMéxico
| | - Ana E. Bunt
- Departamento de Fisiología de la NutriciónInstituto Nacional de Ciencias Médicas y Nutrición Salvador ZubiránMéxico CityMéxico
| | - Gabriela Alemán
- Departamento de Fisiología de la NutriciónInstituto Nacional de Ciencias Médicas y Nutrición Salvador ZubiránMéxico CityMéxico
| | - Claudia C. Marquez‐Mota
- Departamento de Fisiología de la NutriciónInstituto Nacional de Ciencias Médicas y Nutrición Salvador ZubiránMéxico CityMéxico
- Departamento de Nutrición Animal y BioquímicaFMVZ‐UNAMMéxico CityMéxico
| | - Andrea Diaz‐Villaseñor
- Departamento de Fisiología de la NutriciónInstituto Nacional de Ciencias Médicas y Nutrición Salvador ZubiránMéxico CityMéxico
- Instituto de Investigaciones BiomédicasIIB‐UNAMMéxico CityMéxico
| | - Lilia G. Noriega
- Departamento de Fisiología de la NutriciónInstituto Nacional de Ciencias Médicas y Nutrición Salvador ZubiránMéxico CityMéxico
| | - Isabela Estrada
- Departamento de Fisiología de la NutriciónInstituto Nacional de Ciencias Médicas y Nutrición Salvador ZubiránMéxico CityMéxico
| | - Elizabeth Figueroa‐Juárez
- Departamento de Nefrología y Metabolismo MineralInstituto Nacional de Ciencias Médicas y Nutrición Salvador ZubiránMéxico CityMéxico
| | - Claudia Tovar‐Palacio
- Departamento de Nefrología y Metabolismo MineralInstituto Nacional de Ciencias Médicas y Nutrición Salvador ZubiránMéxico CityMéxico
| | - Leonardo A. Rodriguez‐López
- Departamento de Fisiología de la NutriciónInstituto Nacional de Ciencias Médicas y Nutrición Salvador ZubiránMéxico CityMéxico
| | - Patricia López‐Romero
- Departamento de Fisiología de la NutriciónInstituto Nacional de Ciencias Médicas y Nutrición Salvador ZubiránMéxico CityMéxico
| | - Nimbe Torres
- Departamento de Fisiología de la NutriciónInstituto Nacional de Ciencias Médicas y Nutrición Salvador ZubiránMéxico CityMéxico
| | - Armando R. Tovar
- Departamento de Fisiología de la NutriciónInstituto Nacional de Ciencias Médicas y Nutrición Salvador ZubiránMéxico CityMéxico
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17
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Tu HC, Hsiao YC, Yang WY, Tsai SL, Lin HK, Liao CY, Lu JW, Chou YT, Wang HD, Yuh CH. Up-regulation of golgi α-mannosidase IA and down-regulation of golgi α-mannosidase IC activates unfolded protein response during hepatocarcinogenesis. Hepatol Commun 2017; 1:230-247. [PMID: 29404456 PMCID: PMC5721452 DOI: 10.1002/hep4.1032] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/14/2016] [Revised: 02/27/2017] [Accepted: 03/09/2017] [Indexed: 12/27/2022] Open
Abstract
α‐1,2 mannosidases, key enzymes in N‐glycosylation, are required for the formation of mature glycoproteins in eukaryotes. Aberrant regulation of α‐1,2 mannosidases can result in cancer, although the underlying mechanisms are unclear. Here, we report the distinct roles of α‐1,2 mannosidase subtypes (MAN1A, MAN1B, ERMAN1, MAN1C) in the formation of hepatocellular carcinoma (HCC). Clinicopathological analyses revealed that the clinical stage, tumor size, α‐fetoprotein level, and invasion status were positively correlated with the expression levels of MAN1A1, MAN1B1, and MAN1A2. In contrast, the expression of MAN1C1 was decreased as early as stage I of HCC. Survival analyses showed that high MAN1A1, MAN1A2, and MAN1B1 expression levels combined with low MAN1C1 expression levels were significantly correlated with shorter overall survival rates. Functionally, the overexpression of MAN1A1 promoted proliferation, migration, and transformation as well as in vivo migration in zebrafish. Conversely, overexpression of MAN1C1 reduced the migration ability both in vitro and in vivo, decreased the colony formation ability, and shortened the S phase of the cell cycle. Furthermore, the expression of genes involved in cell cycle/proliferation and migration was increased in MAN1A1‐overexpressing cells but decreased in MAN1C1‐overexpressing cells. MAN1A1 activated the expression of key regulators of the unfolded protein response (UPR), while treatment with endoplasmic reticulum stress inhibitors blocked the expression of MAN1A1‐activated genes. Using the MAN1A1 liver‐specific overexpression zebrafish model, we observed steatosis and inflammation at earlier stages and HCC formation at a later stage accompanied by the increased expression of the UPR modulator binding immunoglobulin protein (BiP). These data suggest that the up‐regulation of MAN1A1 activates the UPR and might initiate metastasis. Conclusion: MAN1A1 represents a novel oncogene while MAN1C1 plays a role in tumor suppression in hepatocarcinogenesis. (Hepatology Communications 2017;1:230‐247)
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Affiliation(s)
- Hsiao-Chen Tu
- Institute of Molecular and Genomic Medicine National Health Research Institutes Zhunan Miaoli Taiwan.,Institute of Biotechnology National Tsing-Hua University Hsinchu Taiwan
| | - Yung-Chun Hsiao
- Institute of Molecular and Genomic Medicine National Health Research Institutes Zhunan Miaoli Taiwan.,Institute of Biotechnology National Tsing-Hua University Hsinchu Taiwan
| | - Wan-Yu Yang
- Institute of Molecular and Genomic Medicine National Health Research Institutes Zhunan Miaoli Taiwan
| | - Shin-Lin Tsai
- Institute of Molecular and Genomic Medicine National Health Research Institutes Zhunan Miaoli Taiwan
| | - Hua-Kuo Lin
- Institute of Molecular and Genomic Medicine National Health Research Institutes Zhunan Miaoli Taiwan
| | - Chong-Yi Liao
- Institute of Molecular and Genomic Medicine National Health Research Institutes Zhunan Miaoli Taiwan.,Institute of Biotechnology National Tsing-Hua University Hsinchu Taiwan
| | - Jeng-Wei Lu
- Institute of Molecular and Genomic Medicine National Health Research Institutes Zhunan Miaoli Taiwan.,Department of Life Sciences National Central University Jhongli City Taoyuan Taiwan
| | - Yu-Ting Chou
- Institute of Molecular and Genomic Medicine National Health Research Institutes Zhunan Miaoli Taiwan.,Institute of Biotechnology National Tsing-Hua University Hsinchu Taiwan
| | - Horng-Dar Wang
- Institute of Biotechnology National Tsing-Hua University Hsinchu Taiwan
| | - Chiou-Hwa Yuh
- Institute of Molecular and Genomic Medicine National Health Research Institutes Zhunan Miaoli Taiwan.,Institute of Bioinformatics and Structural Biology National Tsing-Hua University Hsinchu Taiwan.,Department of Biological Science and Technology National Chiao Tung University Hsinchu Taiwan.,Kaohsiung Medical University Kaohsiung Taiwan
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18
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Sarvani C, Sireesh D, Ramkumar KM. Unraveling the role of ER stress inhibitors in the context of metabolic diseases. Pharmacol Res 2017; 119:412-421. [PMID: 28237513 DOI: 10.1016/j.phrs.2017.02.018] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/02/2016] [Revised: 02/16/2017] [Accepted: 02/20/2017] [Indexed: 02/05/2023]
Abstract
ER stress is provoked by the accumulation of unfolded and misfolded proteins in the ER lumen leading to perturbations in ER homeostasis. ER stress activates a signaling cascade called the Unfolded Protein Response (UPR) which triggers a set of transcriptional and translational events that restore ER homeostasis, promoting cell survival and adaptation. If this adaptive response fails, a terminal UPR program commits such cells to apoptosis. Existing preclinical and clinical evidence testify that prolonged ER stress escalates the risk of several metabolic disorders including diabetes, obesity and dyslipidemia. There have been considerable efforts to develop small molecules that are capable of ameliorating ER stress. Few naturally occurring and synthetic molecules have already been demonstrated for their efficacy in abrogating ER stress in both in vitro and in vivo models of metabolic disorders. This review provides a broad overview of the molecular mechanisms of inhibition of ER stress and its association with various metabolic diseases.
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Affiliation(s)
- Chodisetty Sarvani
- SRM Research Institute, SRM University, Kattankulathur 603 203, Tamilnadu, India
| | - Dornadula Sireesh
- SRM Research Institute, SRM University, Kattankulathur 603 203, Tamilnadu, India
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19
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Lee JM. Nuclear Receptors Resolve Endoplasmic Reticulum Stress to Improve Hepatic Insulin Resistance. Diabetes Metab J 2017; 41:10-19. [PMID: 28236381 PMCID: PMC5328691 DOI: 10.4093/dmj.2017.41.1.10] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/05/2016] [Accepted: 12/02/2016] [Indexed: 12/14/2022] Open
Abstract
Chronic endoplasmic reticulum (ER) stress culminating in proteotoxicity contributes to the development of insulin resistance and progression to type 2 diabetes mellitus. Pharmacologic interventions targeting several different nuclear receptors have emerged as potential treatments for insulin resistance. The mechanistic basis for these antidiabetic effects has primarily been attributed to multiple metabolic and inflammatory functions. Here we review recent advances in our understanding of the association of ER stress with insulin resistance and the role of nuclear receptors in promoting ER stress resolution and improving insulin resistance in the liver.
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Affiliation(s)
- Jae Man Lee
- Department of Biochemistry and Cell Biology, Cell and Matrix Research Institute, Kyungpook National University School of Medicine, Daegu, Korea
- BK21 Plus KNU Biomedical Convergence Program, Department of Biomedical Science, Kyungpook National University School of Medicine, Daegu, Korea.
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20
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Jung TW, Choi KM. Pharmacological Modulators of Endoplasmic Reticulum Stress in Metabolic Diseases. Int J Mol Sci 2016; 17:ijms17020192. [PMID: 26840310 PMCID: PMC4783926 DOI: 10.3390/ijms17020192] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2015] [Revised: 01/20/2016] [Accepted: 01/27/2016] [Indexed: 01/23/2023] Open
Abstract
The endoplasmic reticulum (ER) is the principal organelle responsible for correct protein folding, a step in protein synthesis that is critical for the functional conformation of proteins. ER stress is a primary feature of secretory cells and is involved in the pathogenesis of numerous human diseases, such as certain neurodegenerative and cardiometabolic disorders. The unfolded protein response (UPR) is a defense mechanism to attenuate ER stress and maintain the homeostasis of the organism. Two major degradation systems, including the proteasome and autophagy, are involved in this defense system. If ER stress overwhelms the capacity of the cell's defense mechanisms, apoptotic death may result. This review is focused on the various pharmacological modulators that can protect cells from damage induced by ER stress. The possible mechanisms for cytoprotection are also discussed.
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Affiliation(s)
- Tae Woo Jung
- Division of Endocrinology and Metabolism, Department of Internal Medicine, College of Medicine, Korea University, Seoul 152-703, Korea.
| | - Kyung Mook Choi
- Division of Endocrinology and Metabolism, Department of Internal Medicine, College of Medicine, Korea University, Seoul 152-703, Korea.
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21
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PPARγ Agonists Attenuate Palmitate-Induced ER Stress through Up-Regulation of SCD-1 in Macrophages. PLoS One 2015; 10:e0128546. [PMID: 26061913 PMCID: PMC4464548 DOI: 10.1371/journal.pone.0128546] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2015] [Accepted: 04/28/2015] [Indexed: 12/18/2022] Open
Abstract
Background Clinical trials have shown that treatment of patients with type 2 diabetes with pioglitazone, a peroxisome proliferator-activated receptor (PPAR)γ agonist, reduces cardiovascular events. However, the effect of PPARγ agonists on endoplasmic reticulum (ER) stress that plays an important role in the progression of atherosclerosis has not been determined. We sought to determine the effect of PPARγ agonists on ER stress induced by palmitate, the most abundant saturated fatty acid in the serum. Methods and Results Protein expression of ER stress marker was evaluated by Western blot analysis and stearoyl-CoA desaturase1 (SCD-1) mRNA expression was evaluated by qRT-PCR. Macrophage apoptosis was detected by flowcytometry. Pioglitazone and rosiglitazone reduced palmitate-induced phosphorylation of PERK, a marker of ER stress, in RAW264.7, a murine macrophage cell line. Pioglitazone also suppressed palmitate-induced apoptosis in association with inhibition of CHOP expression, JNK phosphorylation and cleavage of caspase-3. These effects of pioglitazone were reversed by GW9662, a PPARγ antagonist, indicating that PPARγ is involved in this process. PPARγ agonists increased expression of SCD-1 that introduces a double bond on the acyl chain of long-chain fatty acid. 4-(2-Chlorophenoxy)-N-(3-(3-methylcarbamoyl)phenyl)piperidine-1-carboxamide, an inhibitor of SCD-1, abolished the anti-ER stress and anti-apoptotic effects of pioglitazone. These results suggest that PPARγ agonists attenuate palmitate-induced ER stress and apoptosis through SCD-1 induction. Up-regulation of SCD-1 may contribute to the reduction of cardiovascular events by treatment with PPARγ agonists.
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22
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Kim SR, Lee YC. Endoplasmic reticulum stress and the related signaling networks in severe asthma. ALLERGY, ASTHMA & IMMUNOLOGY RESEARCH 2015; 7:106-17. [PMID: 25729617 PMCID: PMC4341331 DOI: 10.4168/aair.2015.7.2.106] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/31/2014] [Revised: 04/25/2014] [Accepted: 04/25/2014] [Indexed: 12/25/2022]
Abstract
The endoplasmic reticulum (ER) is a specialized organelle that plays a central role in biosynthesis, correct protein folding, and posttranslational modifications of secretory and membrane proteins. Loss of homeostasis in ER functions triggers the ER stress response, resulting in activation of unfolded protein response (UPR), a hallmark of many inflammatory diseases. These pathways have been reported as critical players in the pathogenesis of various pulmonary disorders, including pulmonary fibrosis, lung injury, and chronic airway disorders. More interestingly, ER stress and the related signaling networks are emerging as important modulators of inflammatory and immune responses in the development of allergen-induced bronchial asthma, especially severe asthma.
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Affiliation(s)
- So Ri Kim
- Department of Internal Medicine, Research Center for Pulmonary Disorders, Chonbuk National University Medical School, Research Institute of Clinical Medicine of Chonbuk National University-Biomedical Research Institute of Chonbuk National University Hospital, Jeonju, Korea
| | - Yong Chul Lee
- Department of Internal Medicine, Research Center for Pulmonary Disorders, Chonbuk National University Medical School, Research Institute of Clinical Medicine of Chonbuk National University-Biomedical Research Institute of Chonbuk National University Hospital, Jeonju, Korea
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23
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Cao Q, Wang X, Jia L, Mondal AK, Diallo A, Hawkins GA, Das SK, Parks JS, Yu L, Shi H, Shi H, Xue B. Inhibiting DNA Methylation by 5-Aza-2'-deoxycytidine ameliorates atherosclerosis through suppressing macrophage inflammation. Endocrinology 2014; 155:4925-38. [PMID: 25251587 PMCID: PMC4239421 DOI: 10.1210/en.2014-1595] [Citation(s) in RCA: 125] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Inflammation marks all stages of atherogenesis. DNA hypermethylation in the whole genome or specific genes is associated with inflammation and cardiovascular diseases. Therefore, we aimed to study whether inhibiting DNA methylation by DNA methyltransferase inhibitor 5-aza-2'-deoxycytidine (5-aza-dC) ameliorates atherosclerosis in low-density lipoprotein receptor knockout (Ldlr(-/-)) mice. Ldlr(-/-) mice were fed an atherogenic diet and adminisered saline or 5-aza-dC (0.25 mg/kg) for up to 30 weeks. 5-aza-dC treatment markedly decreased atherosclerosis development in Ldlr(-/-) mice without changes in body weight, plasma lipid profile, macrophage cholesterol levels and plaque lipid content. Instead, this effect was associated with decreased macrophage inflammation. Macrophages with 5-aza-dC treatment had downregulated expression of genes involved in inflammation (TNF-α, IL-6, IL-1β, and inducible nitric oxidase) and chemotaxis (CD62/L-selectin, chemokine [C-C motif] ligand 2/MCP-1 [CCL2/MCP-1], CCL5, CCL9, and CCL2 receptor CCR2). This resulted in attenuated macrophage migration and adhesion to endothelial cells and reduced macrophage infiltration into atherosclerotic plaques. 5-aza-dC also suppressed macrophage endoplasmic reticulum stress, a key upstream signal that activates macrophage inflammation and apoptotic pathways. Finally, 5-aza-dC demethylated liver X receptor α (LXRα) and peroxisome proliferator-activated receptor γ1 (PPARγ1) promoters, which are both enriched with CpG sites. This led to overexpression of LXRα and PPARγ, which may be responsible for 5-aza-dC's anti-inflammatory and atheroprotective effect. Our findings provide strong evidence that DNA methylation may play a significant role in cardiovascular diseases and serve as a therapeutic target for prevention and treatment of atherosclerosis.
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Affiliation(s)
- Qiang Cao
- Department of Biology and Center for Obesity Reversal (Q.C., H.S., B.X.), Georgia State University, Atlanta, Georgia; Departments of Internal Medicine (Q.C., X.W., A.K.M., A.D., G.A.H., S.K.D., H.S., B.X.) and Pathology (J.S.P.), Wake Forest School of Medicine, Winston-Salem, North Carolina; Department of Internal Medicine (L.J.), University of Texas, Southwestern Medical Center, Dallas, Texas; Department of Animal and Avian Sciences (L.Y.), University of Maryland, College Park, Maryland; and Department of Biochemistry and Molecular Biology (H.S.), Georgia Regents University, Augusta, Georgia
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Purple perilla extracts allay ER stress in lipid-laden macrophages. PLoS One 2014; 9:e110581. [PMID: 25333946 PMCID: PMC4198214 DOI: 10.1371/journal.pone.0110581] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2014] [Accepted: 09/15/2014] [Indexed: 12/15/2022] Open
Abstract
There is a growing body of evidence that excess lipids, hypoxic stress and other inflammatory signals can stimulate endoplasmic reticulum (ER) stress in metabolic diseases. However, the pathophysiological importance and the underlying mechanisms of this phenomenon remain unknown. The current study investigated that 50 ng/ml oxidized LDL promoted unfolded protein response (UPR) and ER stress in J774A1 murine macrophages, which was blocked by extracts (PPE) of purple Perilla frutescens, a plant of the mint family Lamiaceae. The ER stressor tunicamycin was employed as a positive control. Treating 1–10 µg/ml oxidized LDL for 24 h elicited lipotoxic apoptosis in macrophages with obvious nuclear condensation and DNA fragmentation, which was inhibited by PPE. Tunicamycin and oxidized LDL activated and induced the UPR components of activating transcription factor 6 and ER resident chaperone BiP/Grp78 in temporal manners and such effects were blocked by ≥5 µg/ml PPE. In addition, PPE suppressed the enhanced mRNA transcription and splicing of X-box binding protein 1 (XBP1) by tunicamycin and oxidized LDL. The protein induction and nuclear translocation of XBP1 were deterred in PPE-treated macrophages under ER stress. The induction of ATP-binding cassette transporter A1 (ABCA1), scavenger receptor-B1 (SR-B1) and intracellular adhesion molecule-1 (ICAM-1) was abolished by the ER stressor in activated macrophages. The protein induction of ABCA1 and ICAM1 but not SR-B1 was retrieved by adding 10 µg/ml PPE to cells. These results demonstrate that PPE inhibited lipotoxic apoptosis and demoted the induction and activation of UPR components in macrophages. PPE restored normal proteostasis in activated macrophages oxidized LDL. Therefore, PPE was a potent agent antagonizing macrophage ER stress due to lipotoxic signals associated with atherosclerosis.
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25
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Chistiakov DA, Sobenin IA, Orekhov AN, Bobryshev YV. Role of endoplasmic reticulum stress in atherosclerosis and diabetic macrovascular complications. BIOMED RESEARCH INTERNATIONAL 2014; 2014:610140. [PMID: 25061609 PMCID: PMC4100367 DOI: 10.1155/2014/610140] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/15/2014] [Accepted: 06/16/2014] [Indexed: 12/16/2022]
Abstract
Age-related changes in endoplasmic reticulum (ER) are associated with stress of this cell organelle. Unfolded protein response (UPR) is a normal physiological reaction of a cell in order to prevent accumulation of unfolded and misfolded proteins in the ER and improve the normal ER function. However, in pathologic conditions such as atherosclerosis, obesity, and diabetes, ER function becomes impaired, leading to the development of ER stress. In chronic ER stress, defective posttranslational protein folding results in deposits of aberrantly folded proteins in the ER and the induction of cell apoptosis mediated by UPR sensors C/EBPα-homologous protein (CHOP) and inositol requiring protein-1 (IRE1). Since ER stress and ER-induced cell death play a nonredundant role in the pathogenesis of atherosclerosis and diabetic macrovascular complications, pharmaceutical targeting of ER stress components and pathways may be beneficial in the treatment and prevention of cardiovascular pathology.
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Affiliation(s)
| | - Igor A. Sobenin
- Institute for Atherosclerosis, Skolkovo Innovation Center, Moscow, Russia
- Institute of General Pathology and Pathophysiology, Russian Academy of Sciences, Moscow, Russia
- Russian Cardiology Research and Production Complex, Moscow, Russia
| | - Alexander N. Orekhov
- Institute for Atherosclerosis, Skolkovo Innovation Center, Moscow, Russia
- Institute of General Pathology and Pathophysiology, Russian Academy of Sciences, Moscow, Russia
| | - Yuri V. Bobryshev
- Institute of General Pathology and Pathophysiology, Russian Academy of Sciences, Moscow, Russia
- Faculty of Medicine and St. Vincent's Centre for Applied Medical Research, University of New South Wales, Sydney, NSW 2052, Australia
- School of Medicine, University of Western Sydney, Campbelltown, NSW, Australia
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26
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Crunk AE, Monks J, Murakami A, Jackman M, MacLean PS, Ladinsky M, Bales ES, Cain S, Orlicky DJ, McManaman JL. Dynamic regulation of hepatic lipid droplet properties by diet. PLoS One 2013; 8:e67631. [PMID: 23874434 PMCID: PMC3708958 DOI: 10.1371/journal.pone.0067631] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2013] [Accepted: 05/20/2013] [Indexed: 12/21/2022] Open
Abstract
Cytoplasmic lipid droplets (CLD) are organelle-like structures that function in neutral lipid storage, transport and metabolism through the actions of specific surface-associated proteins. Although diet and metabolism influence hepatic CLD levels, how they affect CLD protein composition is largely unknown. We used non-biased, shotgun, proteomics in combination with metabolic analysis, quantitative immunoblotting, electron microscopy and confocal imaging to define the effects of low- and high-fat diets on CLD properties in fasted-refed mice. We found that the hepatic CLD proteome is distinct from that of CLD from other mammalian tissues, containing enzymes from multiple metabolic pathways. The hepatic CLD proteome is also differentially affected by dietary fat content and hepatic metabolic status. High fat feeding markedly increased the CLD surface density of perilipin-2, a critical regulator of hepatic neutral lipid storage, whereas it reduced CLD levels of betaine-homocysteine S-methyltransferase, an enzyme regulator of homocysteine levels linked to fatty liver disease and hepatocellular carcinoma. Collectively our data demonstrate that the hepatic CLD proteome is enriched in metabolic enzymes, and that it is qualitatively and quantitatively regulated by diet and metabolism. These findings implicate CLD in the regulation of hepatic metabolic processes, and suggest that their properties undergo reorganization in response to hepatic metabolic demands.
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Affiliation(s)
- Amanda E. Crunk
- Graduate Program of Molecular Biology, University of Colorado School of Medicine, Aurora, Colorado, United States of America
- Division of Basic Reproductive Sciences, University of Colorado School of Medicine, Aurora, Colorado, United States of America
| | - Jenifer Monks
- Division of Basic Reproductive Sciences, University of Colorado School of Medicine, Aurora, Colorado, United States of America
| | - Aya Murakami
- Graduate Program of Molecular Biology, University of Colorado School of Medicine, Aurora, Colorado, United States of America
| | - Matthew Jackman
- Division of Endocrinology and Metabolism, University of Colorado School of Medicine, Aurora, Colorado, United States of America
- The Center for Human Nutrition, University of Colorado School of Medicine, Aurora, Colorado, United States of America
- The Colorado Obesity Research Initiative, University of Colorado School of Medicine, Aurora, Colorado, United States of America
| | - Paul S. MacLean
- Division of Endocrinology and Metabolism, University of Colorado School of Medicine, Aurora, Colorado, United States of America
- The Center for Human Nutrition, University of Colorado School of Medicine, Aurora, Colorado, United States of America
- The Colorado Obesity Research Initiative, University of Colorado School of Medicine, Aurora, Colorado, United States of America
| | - Mark Ladinsky
- The Boulder Laboratory for 3D Electron Microscopy, University of Colorado Boulder, Boulder Colorado, United States of America
| | - Elise S. Bales
- Division of Basic Reproductive Sciences, University of Colorado School of Medicine, Aurora, Colorado, United States of America
| | - Shannon Cain
- The Colorado Obesity Research Initiative, University of Colorado School of Medicine, Aurora, Colorado, United States of America
| | - David J. Orlicky
- Department of Pathology, University of Colorado School of Medicine, Aurora, Colorado, United States of America
| | - James L. McManaman
- Graduate Program of Molecular Biology, University of Colorado School of Medicine, Aurora, Colorado, United States of America
- Division of Basic Reproductive Sciences, University of Colorado School of Medicine, Aurora, Colorado, United States of America
- The Center for Human Nutrition, University of Colorado School of Medicine, Aurora, Colorado, United States of America
- The Colorado Obesity Research Initiative, University of Colorado School of Medicine, Aurora, Colorado, United States of America
- * E-mail:
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27
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Takahashi N, Yoshizaki T, Hiranaka N, Suzuki T, Yui T, Akanuma M, Kanazawa K, Yoshida M, Naito S, Fujiya M, Kohgo Y, Ieko M. Endoplasmic reticulum stress suppresses lipin-1 expression in 3T3-L1 adipocytes. Biochem Biophys Res Commun 2013; 431:25-30. [PMID: 23291236 DOI: 10.1016/j.bbrc.2012.12.112] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2012] [Accepted: 12/14/2012] [Indexed: 01/04/2023]
Abstract
Lipin-1 plays crucial roles in the regulation of lipid metabolism and cell differentiation in adipocytes. In obesity, adipose lipin-1 mRNA expression is decreased and positively correlated with systemic insulin sensitivity. Amelioration of the lipin-1 depletion might be improved dysmetabolism. Although some cytokines such as TNF-α and interleukin-1β reduces adipose lipin-1 expression, the mechanism of decreased adipose lipin-1 expression in obesity remains unclear. Recently, endoplasmic reticulum (ER) stress is implicated in the pathogenesis of obesity. Here we investigated the role of ER stress on the lipin-1 expression in 3T3-L1 adipocytes. We demonstrated that lipin-1 expression was suppressed by the treatment with ER stress inducers (tunicamycin and thapsigargin) at transcriptional level. We also showed that constitutive lipin-1 expression could be maintained by peroxisome proliferator-activated receptor-γ in 3T3-L1 adipocytes. Activation of peroxisome proliferator-activated receptor-γ recovered the ER stress-induced lipin-1 suppression. These results suggested that ER stress might be involved in the pathogenesis of obesity through lipin-1 depletion.
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Affiliation(s)
- Nobuhiko Takahashi
- Department of Internal Medicine, School of Dentistry, Health Sciences University of Hokkaido, 1757, Kanazawa, Ishikari-Toubetsu, Hokkaido 061-0023, Japan.
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28
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Kang SB, Kim HM, Kim HJ, Seok H, Huh JH, Lee BW, Kang ES, Lee HC, Cha BS. Rosiglitazone attenuates casein-induced hepatic endoplasmic reticulum stress in Sprague-Dawley rats: a novel model of endoplasmic reticulum stress. Endocr J 2013; 60:1231-40. [PMID: 23965360 DOI: 10.1507/endocrj.ej13-0167] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
The proteins found in cow milk have been reported to cause systemic inflammation. Endoplasmic reticulum (ER) stress is known to be involved in the development of several metabolic disorders including insulin resistance and non-alcoholic fatty liver disease. However, the effect of thiazolidinediones (TZDs) on ER stress is still controversial. This is why we want to investigate in this study whether casein, which is the major protein in cow's milk, induces ER stress in the liver and whether rosiglitazone can attenuate these changes. Nine-week-old male Sprague-Dawley (SD) rats were separated into three groups: (1) vehicle treated; (2) daily subcutaneous injections of 1 mL 10% casein; (3) daily subcutaneous injection of 1 mL 10% casein and rosiglitazone 4 mg/[kg d]. After 6 weeks, body weight, food intake, glucose and lipid parameters, and serum AST/ALT levels were measured after an overnight fast. Real time RT-PCR and immunohistochemical staining for various ER stress markers were performed, and a TUNEL analysis was also performed. After 6 weeks, casein injection induced weight reduction, systemic inflammation, and hepatic dysfunction in SD rats. Casein injection increased both the gene and protein expression of ER stress markers in the liver and also caused hepatocyte apoptosis. Rosiglitazone treatment attenuated casein-induced systemic inflammation, ER stress, deteriorated liver function, and increased apoptosis. In conclusion, our results may provide further insight into the effects of casein on chronic inflammatory diseases, and to have a better understanding of the mechanism of the anti-inflammatory properties of rosiglitazone regardless of its hypoglycemic effect.
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Affiliation(s)
- Saet Byol Kang
- Brain Korea 21 project for Medical Science, Yonsei University College of Medicine, Seoul, Korea
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Pei L, Yang J, Du J, Liu H, Ao N, Zhang Y. Downregulation of chemerin and alleviation of endoplasmic reticulum stress by metformin in adipose tissue of rats. Diabetes Res Clin Pract 2012; 97:267-75. [PMID: 22445233 DOI: 10.1016/j.diabres.2012.02.023] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/18/2011] [Revised: 01/16/2012] [Accepted: 02/23/2012] [Indexed: 11/30/2022]
Abstract
AIMS To investigate whether metformin regulates chemerin expression in vivo by alleviating ER stress. METHODS Male Sprague-Dawley rats were fed a high-fat or normal diet for 10 weeks to induce insulin resistance. During the following 6 weeks, the rats were divided into four groups: normal diet without treatment (NC), normal diet with metformin treatment (NM), high-fat diet without metformin (HF), and high-fat diet with metformin (HM). Body weight, fasting glucose, basal insulin level, insulin sensitivity, chemerin expression in serum and adipose tissue, ER stress marker and its pathway were measured. RESULTS After 6 weeks treatment, metformin reduced the body weight gain and enhanced insulin sensitivity of high-fat fed rats. The basal insulin level in the HM group was lower than in the HF group. Metformin reduced chemerin expression in the HM group compared with HF. Metformin reduced the GRP78 mRNA expression in HM rats. Activation of IRE1 alpha was lower in the HM group than the HF group. CONCLUSIONS Metformin treatment decreased the chemerin expression and alleviated the ER stress in the visceral adipose tissue of high-fat diet-induced insulin-resistant rats. These data may also provide a further rationale for exploring the use of metformin in the treatment of insulin resistance.
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Affiliation(s)
- Lina Pei
- Department of Endocrinology and Metabolism, The 1st Affiliated Hospital, China Medical University, Shenyang, China
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30
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Kang JH, Chang YC, Maurizi MR. 4-O-carboxymethyl ascochlorin causes ER stress and induced autophagy in human hepatocellular carcinoma cells. J Biol Chem 2012; 287:15661-71. [PMID: 22433868 DOI: 10.1074/jbc.m112.358473] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
The synthetic derivative of ascochlorin, 4-O-carboxymethyl ascochlorin (AS-6) is an agonist of the nuclear hormone receptor PPARγ and has been shown to induce differentiation in mouse pre-adipocytes and to ameliorate type II diabetes in a murine model. AS-6 was cytotoxic when added at micromolar concentrations to cultures of three different human cancer cell lines. We used gel electrophoresis and mass spectrometry to identify proteins with altered expression in human hepatocarcinoma cells (HepG2) cells after 12 h in the presence of AS-6 and found 58 proteins that were differentially expressed. Many of the proteins showing increased expression in cells treated with AS-6 are involved in protein quality control, including glucose-regulated protein 78 (GRP78/BiP), a regulator of ER stress responses, and the transcriptional regulator CHOP, which mediates ER stress-induced apoptosis. Cells treated with AS-6 undergo an autophagic response accompanied by increased expression of beclin1, ATG5, and LC3-II and autophagosome formation marked by the appearance of large vesicles containing LC3-II. Grp78 induction was inhibited when the PPARγ antagonist, GW9662, was added together with AS-6, and autophagy and cell death were partially blocked. 3-methyl-adenine (3-MA), an inhibitor of phosphatidyl inositol 3-kinase (PI3-kinase) prevented induction of ATG5 and activation of LC3-II and blocked autophagosome formation. 3-MA also blocked induction of GRP78 and CHOP, suggesting that PI3-kinase, which is known to mediate ER stress-induced autophagy, also plays a role in initiating apoptosis in response to ER stress. Together these data establish that the cytotoxicity of AS-6 operates by a mechanism dependent on ER stress-induced autophagy and apoptosis.
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Affiliation(s)
- Jeong Han Kang
- Laboratory of Cell Biology, NCI, National Institutes of Health, Bethesda, Maryland 20892, USA
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31
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Guy CD, Suzuki A, Burchette JL, Brunt EM, Abdelmalek MF, Cardona D, McCall SJ, Ünalp A, Belt P, Ferrell LD, Diehl AM. Costaining for keratins 8/18 plus ubiquitin improves detection of hepatocyte injury in nonalcoholic fatty liver disease. Hum Pathol 2011; 43:790-800. [PMID: 22036053 DOI: 10.1016/j.humpath.2011.07.007] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/21/2011] [Revised: 07/05/2011] [Accepted: 07/21/2011] [Indexed: 01/02/2023]
Abstract
Nonalcoholic fatty liver disease is a global health dilemma. The gold standard for diagnosis is liver biopsy. Ballooned hepatocytes are histologic manifestations of hepatocellular injury and are characteristic of steatohepatitis, the more severe form of nonalcoholic fatty liver disease. Definitive histologic identification of ballooned hepatocytes on routine stains, however, can be difficult. Immunohistochemical evidence for loss of the normal hepatocytic keratin 8/18 can serve as an objective marker of ballooned hepatocytes. We sought to explore the utility of a keratin 8/18 plus ubiquitin double immunohistochemical stain for the histologic evaluation of adult nonalcoholic fatty liver disease. Double immunohistochemical staining for keratin 8/18 and ubiquitin was analyzed using 40 adult human nonalcoholic fatty liver disease core liver biopsies. Ballooned hepatocytes lack keratin 8/18 staining as previously shown by others, but normal-size hepatocytes with keratin loss are approximately 5 times greater in number than keratin-negative ballooned hepatocytes. Keratin-negative ballooned hepatocytes, normal-size hepatocytes with keratin loss, and ubiquitin deposits show a zonal distribution, are positively associated with each other, and are frequently found adjacent to or intermixed with fibrous matrix. All 3 lesions correlate with fibrosis stage and the hematoxylin and eosin diagnosis of steatohepatitis (all P < .05). Compared with hematoxylin and eosin staining, immunohistochemical staining improves the receiver operating characteristics curve for advanced fibrosis (0.77 versus 0.83, 0.89, and 0.89 for keratin-negative ballooned hepatocytes, normal-size hepatocytes with keratin loss, and ubiquitin, respectively) because immunohistochemistry is more sensitive and specific for fibrogenic hepatocellular injury than hematoxylin and eosin staining. Keratin 8/18 plus ubiquitin double immunohistochemical stain improves detection of hepatocyte injury in nonalcoholic fatty liver disease. Thus, it may help differentiate nonalcoholic steatohepatitis from nonalcoholic fatty liver.
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Affiliation(s)
- Cynthia D Guy
- Department of Pathology, Duke University Medical Center, Durham, NC 27710, USA
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32
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Ueno T, Nakamura A, Nakayama H, Otabe S, Yuan X, Fukutani T, Iwamoto H, Nakamura T, Koga H, Torimura T, Sata M, Yamada K. Adiponectin suppresses endoplasmic reticulum stress in nonalcoholic steatohepatitis. Exp Ther Med 2011; 2:1035-1040. [PMID: 22977616 DOI: 10.3892/etm.2011.348] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2011] [Accepted: 08/22/2011] [Indexed: 01/12/2023] Open
Abstract
In this study, we examined whether adiponectin suppresses endoplasmic reticulum (ER) stress in nonalcoholic steatohepatitis (NASH) using male transgenic mice expressing nSREBP-1c in adipose tissue, nSREBP-1c/adiponectin double-transgenic mice expressing human adiponectin in the liver, and wild-type male mice as the control. Histological findings similar to those observed in liver specimens from patients with NASH were observed in the livers from the nSREBP-1c transgenic mice at 30 weeks of age. By contrast, the NASH-like liver histology was markedly attenuated in age-matched nSREBP-1c/adiponectin double-transgenic mice. The nSREBP-1c/adiponectin double-transgenic mice showed human adiponectin production in the liver and a restored circulating human adiponectin level. Human adiponectin messenger ribonucleic acid (mRNA) expression in the liver was identified in the nSREBP-1c/adiponectin double-transgenic mice, but adiponectin receptor 1 and 2 mRNA expression in the liver was normal. TNFα mRNA was decreased in the liver of the nSREBP-1c/adiponectin double-transgenic mice compared with the nSREBP-1c transgenic mice. The protein expressions of X-box-binding protein-1, activating transcription factor 4, acetyl-CoA carboxylase, TNFα and NFκB were down-regulated in liver tissues from the nSREBP-1c/adiponectin double-transgenic mice. Mouse adiponectin and activating transcription factor 6 expressions were almost the same in the three groups. Post-load plasma glucose levels were significantly lower in the nSREBP-1c/adiponectin double-transgenic mice compared with the nSREBP-1c transgenic mice. These results indicate that adiponectin expressed in the liver suppresses ER stress and attenuates hepatic steatosis, inflammation and insulin resistance in NASH. Adiponectin may open the way to novel therapies for human NASH.
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Affiliation(s)
- Takato Ueno
- Research Center for Innovative Cancer Therapy, Kurume University
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Garbow JR, Doherty JM, Schugar RC, Travers S, Weber ML, Wentz AE, Ezenwajiaku N, Cotter DG, Brunt EM, Crawford PA. Hepatic steatosis, inflammation, and ER stress in mice maintained long term on a very low-carbohydrate ketogenic diet. Am J Physiol Gastrointest Liver Physiol 2011; 300:G956-67. [PMID: 21454445 PMCID: PMC3119109 DOI: 10.1152/ajpgi.00539.2010] [Citation(s) in RCA: 119] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/07/2010] [Accepted: 03/29/2011] [Indexed: 01/31/2023]
Abstract
Low-carbohydrate diets are used to manage obesity, seizure disorders, and malignancies of the central nervous system. These diets create a distinctive, but incompletely defined, cellular, molecular, and integrated metabolic state. Here, we determine the systemic and hepatic effects of long-term administration of a very low-carbohydrate, low-protein, and high-fat ketogenic diet, serially comparing these effects to a high-simple-carbohydrate, high-fat Western diet and a low-fat, polysaccharide-rich control chow diet in C57BL/6J mice. Longitudinal measurement of body composition, serum metabolites, and intrahepatic fat content, using in vivo magnetic resonance spectroscopy, reveals that mice fed the ketogenic diet over 12 wk remain lean, euglycemic, and hypoinsulinemic but accumulate hepatic lipid in a temporal pattern very distinct from animals fed the Western diet. Ketogenic diet-fed mice ultimately develop systemic glucose intolerance, hepatic endoplasmic reticulum stress, steatosis, cellular injury, and macrophage accumulation, but surprisingly insulin-induced hepatic Akt phosphorylation and whole-body insulin responsiveness are not impaired. Moreover, whereas hepatic Pparg mRNA abundance is augmented by both high-fat diets, each diet confers splice variant specificity. The distinctive nutrient milieu created by long-term administration of this low-carbohydrate, low-protein ketogenic diet in mice evokes unique signatures of nonalcoholic fatty liver disease and whole-body glucose homeostasis.
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Affiliation(s)
- Joel R Garbow
- Department of 1Medicine, Washington University, St. Louis, Missouri 63110, USA
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Malhi H, Kaufman RJ. Endoplasmic reticulum stress in liver disease. J Hepatol 2011; 54:795-809. [PMID: 21145844 PMCID: PMC3375108 DOI: 10.1016/j.jhep.2010.11.005] [Citation(s) in RCA: 887] [Impact Index Per Article: 68.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/10/2010] [Revised: 10/26/2010] [Accepted: 11/03/2010] [Indexed: 02/06/2023]
Abstract
The unfolded protein response (UPR) is activated upon the accumulation of misfolded proteins in the endoplasmic reticulum (ER) that are sensed by the binding immunoglobulin protein (BiP)/glucose-regulated protein 78 (GRP78). The accumulation of unfolded proteins sequesters BiP so it dissociates from three ER-transmembrane transducers leading to their activation. These transducers are inositol requiring (IRE) 1α, PKR-like ER kinase (PERK), and activating transcription factor (ATF) 6α. PERK phosphorylates eukaryotic initiation factor 2 alpha (eIF2α) resulting in global mRNA translation attenuation, and concurrently selectively increases the translation of several mRNAs, including the transcription factor ATF4, and its downstream target CHOP. IRE1α has kinase and endoribonuclease (RNase) activities. IRE1α autophosphorylation activates the RNase activity to splice XBP1 mRNA, to produce the active transcription factor sXBP1. IRE1α activation also recruits and activates the stress kinase JNK. ATF6α transits to the Golgi compartment where it is cleaved by intramembrane proteolysis to generate a soluble active transcription factor. These UPR pathways act in concert to increase ER content, expand the ER protein folding capacity, degrade misfolded proteins, and reduce the load of new proteins entering the ER. All of these are geared toward adaptation to resolve the protein folding defect. Faced with persistent ER stress, adaptation starts to fail and apoptosis occurs, possibly mediated through calcium perturbations, reactive oxygen species, and the proapoptotic transcription factor CHOP. The UPR is activated in several liver diseases; including obesity associated fatty liver disease, viral hepatitis, and alcohol-induced liver injury, all of which are associated with steatosis, raising the possibility that ER stress-dependent alteration in lipid homeostasis is the mechanism that underlies the steatosis. Hepatocyte apoptosis is a pathogenic event in several liver diseases, and may be linked to unresolved ER stress. If this is true, restoration of ER homeostasis prior to ER stress-induced cell death may provide a therapeutic rationale in these diseases. Herein we discuss each branch of the UPR and how they may impact hepatocyte function in different pathologic states.
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Affiliation(s)
- Harmeet Malhi
- Division of Gastroenterology and Hepatology, College of Medicine, Mayo Clinic, Rochester, MN, USA
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35
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Minamino T, Komuro I, Kitakaze M. Endoplasmic reticulum stress as a therapeutic target in cardiovascular disease. Circ Res 2010; 107:1071-82. [PMID: 21030724 DOI: 10.1161/circresaha.110.227819] [Citation(s) in RCA: 374] [Impact Index Per Article: 26.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Cardiovascular disease constitutes a major and increasing health burden in developed countries. Although treatments have progressed, the development of novel treatments for patients with cardiovascular diseases remains a major research goal. The endoplasmic reticulum (ER) is the cellular organelle in which protein folding, calcium homeostasis, and lipid biosynthesis occur. Stimuli such as oxidative stress, ischemic insult, disturbances in calcium homeostasis, and enhanced expression of normal and/or folding-defective proteins lead to the accumulation of unfolded proteins, a condition referred to as ER stress. ER stress triggers the unfolded protein response (UPR) to maintain ER homeostasis. The UPR involves a group of signal transduction pathways that ameliorate the accumulation of unfolded protein by increasing ER-resident chaperones, inhibiting protein translation and accelerating the degradation of unfolded proteins. The UPR is initially an adaptive response but, if unresolved, can lead to apoptotic cell death. Thus, the ER is now recognized as an important organelle in deciding cell life and death. There is compelling evidence that the adaptive and proapoptotic pathways of UPR play fundamental roles in the development and progression of cardiovascular diseases, including heart failure, ischemic heart diseases, and atherosclerosis. Thus, therapeutic interventions that target molecules of the UPR component and reduce ER stress will be promising strategies to treat cardiovascular diseases. In this review, we summarize the recent progress in understanding UPR signaling in cardiovascular disease and its related therapeutic potential. Future studies may clarify the most promising molecules to be investigated as targets for cardiovascular diseases.
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Affiliation(s)
- Tetsuo Minamino
- Department of Cardiovascular Medicine, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka, Japan.
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Lim S, Cho YM, Park KS, Lee HK. Persistent organic pollutants, mitochondrial dysfunction, and metabolic syndrome. Ann N Y Acad Sci 2010; 1201:166-76. [PMID: 20649553 DOI: 10.1111/j.1749-6632.2010.05622.x] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
The number of individuals with metabolic syndrome is increasing worldwide, constituting a major social problem in many countries. Recently, epidemiological and experimental studies have associated insulin resistance or type 2 diabetes with elevated body burdens of persistent organic pollutants (POPs). It has been proposed that mitochondrial dysfunction plays a key role in this association. Mitochondrial DNA abnormalities are known to cause pancreas beta cell damage, insulin resistance, and diabetes mellitus. Recently, much evidence has emerged showing that environmental toxins, including POPs, affect mitochondrial function and subsequently induce insulin resistance. In this review, we present a novel concept in which metabolic syndrome is the result of mitochondrial dysfunction, which in turn is caused by exposure to POPs. The potential mechanism including POPs for mitochondrial dysfunction on metabolic syndrome is also discussed. We propose that the mitochondrial paradigm for the etiology of metabolic syndrome will facilitate the prevention and treatment of this major health problem.
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Affiliation(s)
- Soo Lim
- Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea
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Abstract
PURPOSE OF REVIEW To provide an overview of the emerging role of cellular stress responses in inflammatory bowel disease (IBD). RECENT FINDINGS The unfolded protein response (UPR) is a primitive cellular pathway that is engaged when responding to endoplasmic reticulum stress and regulates autophagy. Highly secretory cells such as Paneth cells and goblet cells in the intestines are particularly susceptible to endoplasmic reticulum stress and are exceedingly dependent upon a properly functioning UPR to maintain cellular viability and homeostasis. Primary genetic abnormalities within the components of the UPR (e.g. XBP1, ARG2, ORMDL3), genes that encode proteins reliant upon a robust secretory pathway (e.g. MUC2, HLAB27) and environmental factors that create disturbances in the UPR (e.g. microbial products and inflammatory cytokines) are important factors in the primary development and/or perpetuation of intestinal inflammation. SUMMARY Endoplasmic reticulum stress is an important new pathway involved in the development of intestinal inflammation associated with IBD and likely other intestinal inflammatory disorders.
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Abstract
The endoplasmic reticulum (ER) is a cellular compartment responsible for multiple important cellular functions including the biosynthesis and folding of newly synthesized proteins destined for secretion, such as insulin. A myriad of pathological and physiological factors perturb ER function and cause dysregulation of ER homeostasis, leading to ER stress. Accumulating evidence suggests that ER stress plays a role in the pathogenesis of diabetes, contributing to pancreatic β-cell loss and insulin resistance. ER stress may also link obesity, inflammation and insulin resistance in type 2 diabetes. In this review, we address the transition from physiology to pathology, namely how and why the physiological UPR evolves to a proapoptotic ER stress response in diabetes and its complications. Special attention was given to elucidate how ER stress could explain some of the 'clinical paradoxes' such as secondary sulfonylurea failure, initial worsening of retinopathy during tight glycemic control, insulin resistance induced by protease inhibitors and other clinically relevant observations.
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