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Ma YN, Jiang X, Tang W, Song P. Influence of intermittent fasting on autophagy in the liver. Biosci Trends 2023; 17:335-355. [PMID: 37661370 DOI: 10.5582/bst.2023.01207] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/05/2023]
Abstract
Studies have found that intermittent fasting (IF) can prevent diabetes, cancer, heart disease, and neuropathy, while in humans it has helped to alleviate metabolic syndrome, asthma, rheumatoid arthritis, Alzheimer's disease, and many other disorders. IF involves a series of coordinated metabolic and hormonal changes to maintain the organism's metabolic balance and cellular homeostasis. More importantly, IF can activate hepatic autophagy, which is important for maintaining cellular homeostasis and energy balance, quality control, cell and tissue remodeling, and defense against extracellular damage and pathogens. IF affects hepatic autophagy through multiple interacting pathways and molecular mechanisms, including adenosine monophosphate (AMP)-activated protein kinase (AMPK), mammalian target of rapamycin (mTOR), silent mating-type information regulatory 2 homolog-1 (SIRT1), peroxisomal proliferator-activated receptor alpha (PPARα) and farnesoid X receptor (FXR), as well as signaling pathways and molecular mechanisms such as glucagon and fibroblast growth factor 21 (FGF21). These pathways can stimulate the pro-inflammatory cytokines interleukin 6 (IL-6) and tumor necrosis factor α (TNF-α), play a cytoprotective role, downregulate the expression of aging-related molecules, and prevent the development of steatosis-associated liver tumors. By influencing the metabolism of energy and oxygen radicals as well as cellular stress response systems, IF protects hepatocytes from genetic and environmental factors. By activating hepatic autophagy, IF has a potential role in treating a variety of liver diseases, including non-alcoholic fatty liver disease, drug-induced liver injury, viral hepatitis, hepatic fibrosis, and hepatocellular carcinoma. A better understanding of the effects of IF on liver autophagy may lead to new approaches for the prevention and treatment of liver disease.
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Affiliation(s)
- Ya-Nan Ma
- Department of Gastroenterology, Hainan General Hospital, Hainan Affiliated Hospital of Hainan Medical University, Haikou, China
- Center for Clinical Sciences, National Center for Global Health and Medicine, Tokyo, Japan
| | - Xuemei Jiang
- Department of Gastroenterology, Hainan General Hospital, Hainan Affiliated Hospital of Hainan Medical University, Haikou, China
| | - Wei Tang
- International Health Care Center, National Center for Global Health and Medicine, Tokyo, Japan
- Hepato-Biliary-Pancreatic Surgery Division, Department of Surgery, The University of Tokyo Hospital, Tokyo, Japan
| | - Peipei Song
- Center for Clinical Sciences, National Center for Global Health and Medicine, Tokyo, Japan
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Zhao W, Lei M, Li J, Zhang H, Zhang H, Han Y, Ba Z, Zhang M, Li D, Liu C. Yes-associated protein inhibition ameliorates liver fibrosis and acute and chronic liver failure by decreasing ferroptosis and necroptosis. Heliyon 2023; 9:e15075. [PMID: 37151632 PMCID: PMC10161368 DOI: 10.1016/j.heliyon.2023.e15075] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2022] [Revised: 03/23/2023] [Accepted: 03/27/2023] [Indexed: 04/05/2023] Open
Abstract
Background/aims This study aims to determine which cell death modes contribute most in the progression of cirrhosis and acute-on-chronic liver failure (ACLF), and to investigate whether Yes associated protein (YAP) affects the disease process by regulating cell death. Materials and methods 30C57BL/6 male mice were divided into five groups: control, carbon tetrachloride (CCl4)-induced liver fibrosis model, CCl4+verteporfin, CCl4+lipopolysaccharides (LPS) combined with the D-(+)-Galactosamine (LPS/D-GalN)-induced ACLF model, and ACLF + verteporfin. Patients with chronic hepatitis B (CHB), hepatitis B virus (HBV) related liver cirrhosis or ACLF were enrolled. Histology, immunohistochemistry, transmission electron microscopy, Western blot and ELISA were conducted to assess the roles of YAP and cell death in liver cirrhosis and ACLF, and to explore the effect of YAP inhibition on cell deaths. Results YAP was markedly increased in mice with liver fibrosis and ACLF, along with ferroptosis and necroptosis. Furthermore, YAP inhibition significantly suppressed fibrosis in CCl4-mediated liver fibrosis and ACLF-associated liver injury. Notably, CCl4 induced up-regulation of ACSL4 and RIPK3 and down-regulation of SLC7A11, key factors in ferroptosis and necroptosis. This was significantly abrogated by verteporfin treatment. Similar changes in ferroptosis and necroptosis were found in ACLF and ACLF + verteporfin groups. Consistent with the above findings in mice, we found that plasma YAP levels were gradually increased with the development of HBV-related liver fibrosis and ACLF. Conclusion Ferroptosis and necroptosis are involved in the development of liver cirrhosis and ACLF. Inhibition of YAP improved liver fibrosis and liver damage in ACLF through a reduction in ferroptosis and necroptosis. Our findings may help better understanding the role of YAP in liver fibrosis and ACLF.
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Affiliation(s)
- Wen Zhao
- Department of Infectious Diseases, The First Affiliated Hospital of Bengbu Medical College, Bengbu, 233000, China
- Core Cooperative Unit of National Clinical Research Center for Infectious Diseases, China
- Key Laboratory of Infection and Immunity of Anhui Province, China
| | - Miao Lei
- Department of Infectious Diseases, The First Affiliated Hospital of Bengbu Medical College, Bengbu, 233000, China
- Core Cooperative Unit of National Clinical Research Center for Infectious Diseases, China
- Key Laboratory of Infection and Immunity of Anhui Province, China
| | - Jinfeng Li
- Department of Infectious Diseases, The First Affiliated Hospital of Bengbu Medical College, Bengbu, 233000, China
- Core Cooperative Unit of National Clinical Research Center for Infectious Diseases, China
- Key Laboratory of Infection and Immunity of Anhui Province, China
| | - Hailin Zhang
- Department of Infectious Diseases, The First Affiliated Hospital of Bengbu Medical College, Bengbu, 233000, China
- Core Cooperative Unit of National Clinical Research Center for Infectious Diseases, China
- Key Laboratory of Infection and Immunity of Anhui Province, China
| | - Hongkun Zhang
- Department of Infectious Diseases, The First Affiliated Hospital of Bengbu Medical College, Bengbu, 233000, China
- Core Cooperative Unit of National Clinical Research Center for Infectious Diseases, China
- Key Laboratory of Infection and Immunity of Anhui Province, China
| | - Yuxin Han
- Department of Infectious Diseases, The First Affiliated Hospital of Bengbu Medical College, Bengbu, 233000, China
- Core Cooperative Unit of National Clinical Research Center for Infectious Diseases, China
- Key Laboratory of Infection and Immunity of Anhui Province, China
| | - Zhiwei Ba
- Department of Infectious Diseases, The First Affiliated Hospital of Bengbu Medical College, Bengbu, 233000, China
- Core Cooperative Unit of National Clinical Research Center for Infectious Diseases, China
- Key Laboratory of Infection and Immunity of Anhui Province, China
| | - Manli Zhang
- Department of Infectious Diseases, The First Affiliated Hospital of Bengbu Medical College, Bengbu, 233000, China
- Core Cooperative Unit of National Clinical Research Center for Infectious Diseases, China
- Key Laboratory of Infection and Immunity of Anhui Province, China
| | - Dongdong Li
- Department of Infectious Diseases, The First Affiliated Hospital of Bengbu Medical College, Bengbu, 233000, China
- Core Cooperative Unit of National Clinical Research Center for Infectious Diseases, China
- Key Laboratory of Infection and Immunity of Anhui Province, China
| | - Chuanmiao Liu
- Department of Infectious Diseases, The First Affiliated Hospital of Bengbu Medical College, Bengbu, 233000, China
- Core Cooperative Unit of National Clinical Research Center for Infectious Diseases, China
- Key Laboratory of Infection and Immunity of Anhui Province, China
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Combined physical exercise reverses the reduced expression of Bmal1 in the liver of aged mice. Life Sci 2022; 312:121175. [PMID: 36414092 DOI: 10.1016/j.lfs.2022.121175] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2022] [Revised: 10/28/2022] [Accepted: 11/07/2022] [Indexed: 11/21/2022]
Abstract
Aging can modify the morphology and function of the liver, such as generating a decrease in the mitochondria content, autophagy, and cell senescence. Although exercise training has several beneficial effects on hepatic metabolism, its actions on autophagy processes, mitochondrial function, and cellular senescence need to be more widely explored. The present study verified the effects of aging and exercise on hepatic circadian markers, autophagy, and mitochondria activity in 24-month-old mice with a combined exercise training protocol. In addition, we used public datasets from human livers in several conditions and BMAL1 knockout mice. C57BL/6 mice were distributed into Control (CT, young, 6-month-old mice), sedentary old (Old Sed, sedentary, 24-month-old mice), and exercised old (Old Ex, 24-month-old mice submitted to a combined exercise training protocol). The exercise training protocol consisted of three days of endurance exercise - treadmill running, and two days of resistance exercise - climbing a ladder, for three weeks. At the end of the protocol, the liver was removed and prepared for histological analysis, reverse transcription-quantitative polymerase chain reaction (RT-qPCR), immunoblotting technique, and oxygen consumption. Heatmaps were built using a human dataset and Bmal1 knockout samples. In summary, the Old Sed had reduced strength, coordination, and balance, as well as a decrease in Bmal1 expression and the presence of degenerated liver cells. Still, this group upregulated the transcription factors related to mitochondrial biogenesis. The Old Ex group had increased strength, coordination, and balance, improved glucose sensitivity, as well as restored Bmal1 expression and the mitochondrial transcription factors. The human datasets indicated that mitochondrial markers and autophagy strongly correlate with specific liver diseases but not aging. We can speculate that mitochondrial and autophagy molecular markers alterations may depend on long-term training.
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Cell Autophagy in NASH and NASH-Related Hepatocellular Carcinoma. Int J Mol Sci 2022; 23:ijms23147734. [PMID: 35887082 PMCID: PMC9322157 DOI: 10.3390/ijms23147734] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2022] [Revised: 07/10/2022] [Accepted: 07/11/2022] [Indexed: 12/21/2022] Open
Abstract
Autophagy, a cellular self-digestion process, involves the degradation of targeted cell components such as damaged organelles, unfolded proteins, and intracellular pathogens by lysosomes. It is a major quality control system of the cell and plays an important role in cell differentiation, survival, development, and homeostasis. Alterations in the cell autophagic machinery have been implicated in several disease conditions, including neurodegeneration, autoimmunity, cancer, infection, inflammatory diseases, and aging. In non-alcoholic fatty liver disease, including its inflammatory form, non-alcoholic steatohepatitis (NASH), a decrease in cell autophagic activity, has been implicated in the initial development and progression of steatosis to NASH and hepatocellular carcinoma (HCC). We present an overview of autophagy as it occurs in mammalian cells with an insight into the emerging understanding of the role of autophagy in NASH and NASH-related HCC.
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Pinto AP, Ropelle ER, Quadrilatero J, da Silva ASR. Physical Exercise and Liver Autophagy: Potential Roles of IL-6 and Irisin. Exerc Sport Sci Rev 2022; 50:89-96. [PMID: 34961755 DOI: 10.1249/jes.0000000000000278] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Autophagic dysregulation contributes to liver diseases. Although some investigations have examined the effects of endurance and resistance exercise on autophagy activation, potential myokines responsible for skeletal muscle-liver crosstalk are still unknown. Based on experimental studies and bioinformatics, we hypothesized that interleukin 6 (IL-6) and irisin might be key players in the contraction-induced release of molecules that regulate liver autophagic responses.
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Affiliation(s)
- Ana P Pinto
- Postgraduate Program in Rehabilitation and Functional Performance, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto São Paulo, Brazil
| | - Eduardo R Ropelle
- Laboratory of Molecular Biology of Exercise, School of Applied Sciences, University of Campinas, Limeira, São Paulo, Brazil
| | - Joe Quadrilatero
- Department of Kinesiology, University of Waterloo, Waterloo, ON, Canada
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Byrnes K, Blessinger S, Bailey NT, Scaife R, Liu G, Khambu B. Therapeutic regulation of autophagy in hepatic metabolism. Acta Pharm Sin B 2022; 12:33-49. [PMID: 35127371 PMCID: PMC8799888 DOI: 10.1016/j.apsb.2021.07.021] [Citation(s) in RCA: 44] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2021] [Revised: 05/04/2021] [Accepted: 07/09/2021] [Indexed: 02/07/2023] Open
Abstract
Metabolic homeostasis requires dynamic catabolic and anabolic processes. Autophagy, an intracellular lysosomal degradative pathway, can rewire cellular metabolism linking catabolic to anabolic processes and thus sustain homeostasis. This is especially relevant in the liver, a key metabolic organ that governs body energy metabolism. Autophagy's role in hepatic energy regulation has just begun to emerge and autophagy seems to have a much broader impact than what has been appreciated in the field. Though classically known for selective or bulk degradation of cellular components or energy-dense macromolecules, emerging evidence indicates autophagy selectively regulates various signaling proteins to directly impact the expression levels of metabolic enzymes or their upstream regulators. Hence, we review three specific mechanisms by which autophagy can regulate metabolism: A) nutrient regeneration, B) quality control of organelles, and C) signaling protein regulation. The plasticity of the autophagic function is unraveling a new therapeutic approach. Thus, we will also discuss the potential translation of promising preclinical data on autophagy modulation into therapeutic strategies that can be used in the clinic to treat common metabolic disorders.
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Key Words
- AIM, Atf8 interacting motif
- ATGL, adipose triglyceride lipase
- ATL3, Atlastin GTPase 3
- ATM, ATM serine/threonine kinase
- Autophagy
- BA, bile acid
- BCL2L13, BCL2 like 13
- BNIP3, BCL2 interacting protein 3
- BNIP3L, BCL2 interacting protein 3 like
- CAR, constitutive androstane receptor
- CCPG1, cell cycle progression 1
- CLN3, lysosomal/endosomal transmembrane protein
- CMA, chaperonin mediated autophagy
- CREB, cAMP response element binding protein
- CRY1, cryptochrome 1
- CYP27A1, sterol 27-hydroxylase
- CYP7A1, cholesterol 7α-hydroxylase
- Cryptochrome 1
- DFCP1, double FYVE-containing protein 1
- FAM134B, family with sequence similarity 134, member B
- FFA, free fatty acid
- FOXO1, Forkhead box O1
- FUNDC1, FUN14 domain containing 1
- FXR, farnesoid X receptor
- Farnesoid X receptor
- GABARAPL1, GABA type A receptor associated protein like 1
- GIM, GABARAP-interacting motif
- LAAT-1, lysosomal amino acid transporter 1 homologue
- LALP70, lysosomal apyrase-like protein of 70 kDa
- LAMP1, lysosomal-associated membrane protein-1
- LAMP2, lysosomal-associated membrane protein-2
- LD, lipid droplet
- LIMP1, lysosomal integral membrane protein-1
- LIMP3, lysosomal integral membrane protein-3
- LIR, LC3 interacting region
- LXRa, liver X receptor a
- LYAAT-1, lysosomal amino acid transporter 1
- Liver metabolism
- Lysosome
- MCOLN1, mucolipin 1
- MFSD1, major facilitator superfamily domain containing 1
- NAFLD, non-alcoholic fatty liver disease
- NBR1, BRCA1 gene 1 protein
- NCoR1, nuclear receptor co-repressor 1
- NDP52, calcium-binding and coiled-coil domain-containing protein 2
- NPC-1, Niemann-Pick disease, type C1
- Nutrient regeneration
- OPTN, optineurin
- PEX5, peroxisomal biogenesis factor 5
- PI3K, phosphatidylinositol-4,5-bisphosphate 3-kinase
- PINK1, phosphatase and tensin homolog (PTEN)-induced kinase 1
- PKA, protein kinase A
- PKB, protein kinase B
- PLIN2, perilipin 2
- PLIN3, perilipin 3
- PP2A, protein phosphatase 2a
- PPARα, peroxisomal proliferator-activated receptor-alpha
- PQLC2, PQ-loop protein
- PXR, pregnane X receptor
- Quality control
- RETREG1, reticulophagy regulator 1
- ROS, reactive oxygen species
- RTN3, reticulon 3
- RTNL3, a long isoform of RTN3
- S1PR2, sphingosine-1-phosphate receptor 2
- S6K, P70-S6 kinase
- S6RP, S6 ribosomal protein
- SCARB2, scavenger receptor class B member 2
- SEC62, SEC62 homolog, preprotein translocation factor
- SIRT1, sirtuin 1
- SLC36A1, solute carrier family 36 member 1
- SLC38A7, solute carrier family 38 member 7
- SLC38A9, sodium-coupled neutral amino acid transporter 9
- SNAT7, sodium-coupled neutral amino acid transporter 7
- SPIN, spindling
- SQSTM1, sequestosome 1
- STBD1, starch-binding domain-containing protein 1
- Signaling proteins
- TBK1, serine/threonine-protein kinase
- TEX264, testis expressed 264, ER-phagy receptor
- TFEB/TFE3, transcription factor EB
- TGR5, takeda G protein receptor 5
- TRAC-1, thyroid-hormone-and retinoic acid-receptor associated co-repressor 1
- TRPML1, transient receptor potential mucolipin 1
- ULK1, Unc-51 like autophagy activating kinase 1
- UPR, unfolded protein response
- V-ATPase, vacuolar-ATPase
- VDR, vitamin D3 receptor
- VLDL, very-low-density lipoprotein
- WIPI1, WD repeat domain phosphoinositide-interacting protein 1
- mTORC1, mammalian target of rapamycin complex 1
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Salman A, Aon M, Hussein A, Salman M, Tourky M, Mahmoud A, Aljarad F, Elkaseer M, Shaaban HED, Moustafa A, El-Mikkawy A, Gaballa N, Abdallah H, Zaky Rashed ZF, Elkassar H. Impact of Hypothyroidism on Patients with Hepatocellular Carcinoma Undergoing Liver Transplantation. Int J Gen Med 2021; 14:5711-5718. [PMID: 34557025 PMCID: PMC8455075 DOI: 10.2147/ijgm.s326315] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Accepted: 08/31/2021] [Indexed: 12/23/2022] Open
Abstract
Background This work endeavored to explore the effect of hypothyroidism on mortality in subjects with HCC who underwent living-donor liver transplantation (LDLT). Methods This prospective study included 107 patients with HCC subjected to LDLT, divided into hypothyroid group (n=53) and euthyroid group (n=54). The primary objectives were overall and disease-free survival (DFS). Results Euthyroid and hypothyroid groups were comparable in all baseline characteristics except the age of patients. Overall survival (OS) of the whole group at 48 months was 68.8%, while the DFS was 60.2%. On univariate analysis, OS was negatively affected by the older age of the patients (p<0.001) or the donor (p<0.001), hypothyroidism (p=0.008), HBV (p=0.029), larger tumor size (p=0.023), and defective Milan criteria (p=0.022). On multivariate analysis, the age of the patients and donors was the independent factor affecting OS. On univariate analysis, DFS was negatively affected by older age of the patients (p < 0.001) or the donor (p=0.005), hypothyroidism (p=0.005), HBV (p=0.019), larger tumor size (p=0.023), and defective Milan criteria (p=0.020). On multivariate analysis, the age of the patients, thyroid status, and Milan criteria were the independent factors affecting DFS. Conclusion Hypothyroidism is a risk factor for worse outcomes in HCC patients after liver transplantation.
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Affiliation(s)
- Ahmed Salman
- Internal Medicine Department, Faculty of Medicine, Cairo University, Cairo, Egypt
| | - Mohamed Aon
- Internal Medicine Department, Faculty of Medicine, Cairo University, Cairo, Egypt
| | - Amr Hussein
- Internal Medicine Department, Faculty of Medicine, Al-Azhar University, Cairo, Egypt
| | - Mohamed Salman
- General Surgery Department, Faculty of Medicine, Cairo University, Cairo, Egypt
| | - Mohamed Tourky
- Department of Surgery, Great Western Hospitals NHS Foundation Trust, Swindon, UK
| | - Ahmed Mahmoud
- Senior Clinical Fellow, Great Western Hospital NHS Foundation Trust, Swindon, UK
| | - Feras Aljarad
- Lewisham and Greenwich NHS Trust, Lewisham, London, UK
| | - Mohamed Elkaseer
- General Surgery Department, Faculty of Medicine, Al-Azhar University, Cairo, Egypt
| | - Hossam El-Din Shaaban
- Hepatology and Gastroenterology Department, National Hepatology and Tropical Medicine Research Institute, Cairo, Egypt
| | - Ahmed Moustafa
- Department of Endemic Medicine and Hepatology, Faculty of Medicine, Cairo University, Cairo, Egypt
| | - Ahmed El-Mikkawy
- Hepatology and Gastroenterology Department, Theodor Bilharz Research Institute, Cairo, Egypt
| | - Nahla Gaballa
- Anesthesiology and Intensive Care Department, National Liver Institute, Menoufia University, Shibin El Kom, Egypt
| | - Heba Abdallah
- Clinical Pathology Department, National Liver Institute, Menoufia University, Shibin El Kom, Egypt
| | - Zaky Ftouh Zaky Rashed
- Anesthesiology and Intensive Care Department, Faculty of Medicine, Al-Azhar University, Cairo, Egypt.,Department of Anesthesia, College of Applied Sciences, Almaarefa university, Ad Diriyah, Riyadh, Saudi Arabia
| | - Hesham Elkassar
- Internal Medicine Department, Faculty of Medicine, Cairo University, Cairo, Egypt
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Chen Y, Xu Z, Zeng Y, Liu J, Wang X, Kang Y. Altered metabolism by autophagy defection affect liver regeneration. PLoS One 2021; 16:e0250578. [PMID: 33914811 PMCID: PMC8084245 DOI: 10.1371/journal.pone.0250578] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2020] [Accepted: 04/08/2021] [Indexed: 11/19/2022] Open
Abstract
Autophagy is the primary intracellular catabolic process for degrading and recycling long-lived proteins and damaged organelles, which maintains cellular homeostasis. Autophagy has key roles in development and differentiation. By using the mouse with liver specific knockout of autophagy related gene 5 (Atg5), a gene essential for autophagy, we investigated the possible role of autophagy in liver regeneration after 70% partial hepatectomy (PHx). Ablation of autophagy significantly impaired mouse liver regeneration, and this impairment was associated with reduced hepatocellular proliferation rate, down-regulated expression of cyclins and tumor suppressors, and increased hepatocellular apoptosis via the intrinsic apoptotic pathway. Ablation of autophagy does not affect IL-6 and TNF-α response after PHx, but the altered hepatic and systemic metabolic responses were observed in these mice, including reduced ATP and hepatic free fatty acid levels in the liver tissue, increased glucose level in the serum. Autophagy is required to promote hepatocellular proliferation by maintaining normal hepatic and systemic metabolism and suppress hepatocellular apoptosis in liver regeneration.
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Affiliation(s)
- Yi Chen
- Clinical Research Service Center, Henan Provincia People’s Hospital, Zhengzhou University People’s Hospital, Henan Province, Zhengzhou, China
| | - Zhiwei Xu
- Clinical Research Service Center, Henan Provincia People’s Hospital, Zhengzhou University People’s Hospital, Henan Province, Zhengzhou, China
| | - Yanli Zeng
- Department of Infectious Diseases, Henan Provincia People’s Hospital, Zhengzhou University People’s Hospital, Henan Province, Zhengzhou, China
| | - Junping Liu
- Department of Infectious Diseases, Henan Provincia People’s Hospital, Zhengzhou University People’s Hospital, Henan Province, Zhengzhou, China
| | - Xuemei Wang
- Department of Traditional Chinese Medicine, Henan Provincia People’s Hospital, Zhengzhou University People’s Hospital, Henan Province, Zhengzhou, China
| | - Yi Kang
- Department of Infectious Diseases, Henan Provincia People’s Hospital, Zhengzhou University People’s Hospital, Henan Province, Zhengzhou, China
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Zhang X, Deng Y, Xiang J, Liu H, Zhang J, Liao J, Chen K, Liu B, Liu J, Pu Y. Galangin Improved Non-Alcoholic Fatty Liver Disease in Mice by Promoting Autophagy. DRUG DESIGN DEVELOPMENT AND THERAPY 2020; 14:3393-3405. [PMID: 32884242 PMCID: PMC7443405 DOI: 10.2147/dddt.s258187] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/25/2020] [Accepted: 07/23/2020] [Indexed: 12/16/2022]
Abstract
Background Previous studies have shown that curcumin derivatives can improve the fatty degeneration of liver tissue that occurs in nonalcoholic fatty liver disease (NAFLD). However, the specific mechanism for that improvement remains unclear. We examined whether the curcumin derivative galangin could reduce the fatty degeneration of liver tissue in mice with NAFLD by inducing autophagy, from the perspective of both prevention and treatment. Methods C57BL/6J mice were randomly assigned to a prevention group (given galangin and a HFD simultaneously) or a treatment group (given galangin after being fed an HFD). The prevention group was treated with galangin (100 mg/kg/d) or an equal volume of normal saline (NS) while being fed an HFD. Some mice were treated with an autophagy inhibitor (3-methyladenine, 3-MA; 30 mg/kg/biwk, i.p.) while being fed an HFD and galangin. HepG2 cells were cultured in DMEM medium containing both free fatty acids and galangin. Results Galangin was found to reduce the fatty degeneration of liver tissue induced by eating an HFD at both the prevention and treatment levels, and that effect might be related to an enhancement of hepatocyte autophagy. Inhibition of autophagy by 3-MA blocked the protective effect of galangin on hepatic steatosis. At the cellular level, galangin reduced lipid accumulation and enhanced the level of hepatocyte autophagy. Conclusion In vitro and in vivo studies showed that galangin cannot only improve pre-existing hepatic steatosis but also prevent the development of stenosis by promoting hepatocyte autophagy.
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Affiliation(s)
- Xinxu Zhang
- Department of Geriatric Endocrinology, Xiangya Hospital, Central South University, Changsha, Hunan 410008, People's Republic of China
| | - Yuanyuan Deng
- Department of Geriatric Endocrinology, Xiangya Hospital, Central South University, Changsha, Hunan 410008, People's Republic of China
| | - Juan Xiang
- Department of Geriatric Endocrinology, Xiangya Hospital, Central South University, Changsha, Hunan 410008, People's Republic of China
| | - Huixia Liu
- Department of Geriatric Endocrinology, Xiangya Hospital, Central South University, Changsha, Hunan 410008, People's Republic of China
| | - Jiani Zhang
- Department of Geriatric Endocrinology, Xiangya Hospital, Central South University, Changsha, Hunan 410008, People's Republic of China
| | - Jie Liao
- Department of Geriatric Endocrinology, Xiangya Hospital, Central South University, Changsha, Hunan 410008, People's Republic of China
| | - Ke Chen
- Department of Geriatric Endocrinology, Xiangya Hospital, Central South University, Changsha, Hunan 410008, People's Republic of China
| | - Bo Liu
- Department of Geriatric Endocrinology, Xiangya Hospital, Central South University, Changsha, Hunan 410008, People's Republic of China
| | - Jun Liu
- Department of Geriatric Endocrinology, Xiangya Hospital, Central South University, Changsha, Hunan 410008, People's Republic of China
| | - Ying Pu
- Department of Geriatric Endocrinology, Xiangya Hospital, Central South University, Changsha, Hunan 410008, People's Republic of China
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Activation of autophagic flux via LKB1/AMPK/mTOR axis against xenoestrogen Bisphenol-A exposure in primary rat hepatocytes. Food Chem Toxicol 2020; 141:111314. [DOI: 10.1016/j.fct.2020.111314] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2019] [Revised: 03/07/2020] [Accepted: 03/30/2020] [Indexed: 12/25/2022]
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Honma Y, Sato-Morita M, Katsuki Y, Mihara H, Baba R, Hino K, Kawashima A, Ariyasu T, Harada M. Trehalose alleviates oxidative stress-mediated liver injury and Mallor-Denk body formation via activating autophagy in mice. Med Mol Morphol 2020; 54:41-51. [PMID: 32588144 DOI: 10.1007/s00795-020-00258-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2020] [Accepted: 06/16/2020] [Indexed: 02/06/2023]
Abstract
Autophagy is a degradation pathway for long-lived cytoplasmic proteins or damaged organelles and also for many aggregate-prone and disease-causing proteins. Endoplasmic reticulum (ER) stress and oxidative stress are associated with the pathophysiology of various liver diseases. These stresses induce the accumulation of abnormal proteins, Mallory-Denk body (MDB) formation and apoptosis in hepatocytes. A disaccharide trehalose had been reported to induce autophagy and decrease aggregate-prone proteins and cytotoxicity in neurodegenerative disease models. But the effects of trehalose in hepatocytes have not been fully understood. We examined the effect of trehalose on autophagy, ER stress and oxidative stress-mediated cytotoxicity and MDB formation in hepatocytes using mice model with 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC) treatment for 3 months. We administered trehalose by intraperitoneal injection of water containing 10% trehalose (0.02 mg/g body weight) every other day for 3 months. Our results demonstrated that trehalose induced autophagy and reduced ER stress, oxidative stress, MDB formation and apoptosis in hepatocytes of DDC-fed mice by Western blotting and immunostaining analyses. Electron microscopy revealed that trehalose induced autolysosome formation, which located is close to the MDBs. Thus, our findings suggest that trehalose can become a therapeutic agent for oxidative stress-related liver diseases via activating autophagy.
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Affiliation(s)
- Yuichi Honma
- Third Department of Internal Medicine, School of Medicine, University of Occupational and Environmental Health, 1-1 Iseigaoka, Yahatanishi-ku, Kitakyushu, 807-8555, Japan.
| | - Miyuki Sato-Morita
- Third Department of Internal Medicine, School of Medicine, University of Occupational and Environmental Health, 1-1 Iseigaoka, Yahatanishi-ku, Kitakyushu, 807-8555, Japan
| | - Yuka Katsuki
- Third Department of Internal Medicine, School of Medicine, University of Occupational and Environmental Health, 1-1 Iseigaoka, Yahatanishi-ku, Kitakyushu, 807-8555, Japan
| | - Hitomi Mihara
- Third Department of Internal Medicine, School of Medicine, University of Occupational and Environmental Health, 1-1 Iseigaoka, Yahatanishi-ku, Kitakyushu, 807-8555, Japan
| | - Ryoko Baba
- Department of Anatomy, School of Medicine, University of Occupational and Environmental Health, Kitakyushu, Japan
| | - Katsuhiko Hino
- Core Technology Division, R&D Center, Hayashibara Co., Ltd., Okayama, Japan
| | - Akira Kawashima
- Applied Technology Division, R&D Center, Hayashibara Co., Ltd., Okayama, Japan
| | - Toshio Ariyasu
- Applied Technology Division, R&D Center, Hayashibara Co., Ltd., Okayama, Japan
| | - Masaru Harada
- Third Department of Internal Medicine, School of Medicine, University of Occupational and Environmental Health, 1-1 Iseigaoka, Yahatanishi-ku, Kitakyushu, 807-8555, Japan
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12
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Pinto AP, Vieira TS, Marafon BB, Batitucci G, Cabrera EMB, da Rocha AL, Kohama EB, Rodrigues KCC, de Moura LP, Pauli JR, Cintra DE, Ropelle ER, de Freitas EC, da Silva ASR. The Combination of Fasting, Acute Resistance Exercise, and Protein Ingestion Led to Different Responses of Autophagy Markers in Gastrocnemius and Liver Samples. Nutrients 2020; 12:nu12030641. [PMID: 32121154 PMCID: PMC7146592 DOI: 10.3390/nu12030641] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2020] [Revised: 02/25/2020] [Accepted: 02/26/2020] [Indexed: 12/02/2022] Open
Abstract
The present study verified the responses of proteins related to the autophagy pathway after 10 h of fast with resistance exercise and protein ingestion in skeletal muscle and liver samples. The rats were distributed into five experimental groups: control (CT; sedentary and without gavage after fast), exercise immediately (EXE-imm; after fast, rats were submitted to the resistance protocol and received water by gavage immediately after exercise), exercise after 1 h (EXE-1h; after fast, rats were submitted to the resistance protocol and received water by gavage 1 h after exercise), exercise and supplementation immediately after exercise (EXE/Suppl-imm; after fast, rats were submitted to the resistance protocol and received a mix of casein: whey protein 1:1 (w/w) by gavage immediately after exercise), exercise and supplementation 1 h after exercise (EXE/Suppl-1h; after fast, rats were submitted to the resistance protocol and received a mix of casein: whey protein 1:1 (w/w) by gavage 1 h after exercise). In summary, the current findings show that the combination of fasting, acute resistance exercise, and protein blend ingestion (immediately or 1 h after the exercise stimulus) increased the serum levels of leucine, insulin, and glucose, as well as the autophagy protein contents in skeletal muscle, but decreased other proteins related to the autophagic pathway in the liver. These results deserve further mechanistic investigations since athletes are combining fasting with physical exercise to enhance health and performance outcomes.
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Affiliation(s)
- Ana P. Pinto
- Postgraduate Program in Rehabilitation and Functional Performance, Ribeirão Preto Medical School, University of São Paulo (USP), Ribeirão Preto, São Paulo 14049-900, Brazil; (A.P.P.); (A.L.d.R.); (E.B.K.)
| | - Tales S. Vieira
- Postgraduate Program in Nutritional Science, State University of São Paulo Júlio de Mesquita Filho (Araraquara). Araraquara, São Paulo 14800-903, Brazil; (T.S.V.); (G.B.); (E.C.d.F.)
| | - Bruno B. Marafon
- School of Physical Education and Sport of Ribeirão Preto, University of São Paulo (USP), Ribeirão Preto, São Paulo 14040-907, Brazil;
| | - Gabriela Batitucci
- Postgraduate Program in Nutritional Science, State University of São Paulo Júlio de Mesquita Filho (Araraquara). Araraquara, São Paulo 14800-903, Brazil; (T.S.V.); (G.B.); (E.C.d.F.)
| | - Elisa M. B. Cabrera
- Institute of Translational Nutrigenetics and Nutrigenomics, Department of Molecular Biology and Genomics, Health Sciences University Center, University of Guadalajara, Guadalajara 44100, Mexico;
| | - Alisson L. da Rocha
- Postgraduate Program in Rehabilitation and Functional Performance, Ribeirão Preto Medical School, University of São Paulo (USP), Ribeirão Preto, São Paulo 14049-900, Brazil; (A.P.P.); (A.L.d.R.); (E.B.K.)
| | - Eike B. Kohama
- Postgraduate Program in Rehabilitation and Functional Performance, Ribeirão Preto Medical School, University of São Paulo (USP), Ribeirão Preto, São Paulo 14049-900, Brazil; (A.P.P.); (A.L.d.R.); (E.B.K.)
| | - Kellen C. C. Rodrigues
- Laboratory of Molecular Biology of Exercise (LaBMEx), School of Applied Sciences, University of Campinas (UNICAMP), Limeira, São Paulo 13484-350, Brazil; (K.C.C.R.); (L.P.d.M.); (J.R.P.); (D.E.C.); (E.R.R.)
| | - Leandro P. de Moura
- Laboratory of Molecular Biology of Exercise (LaBMEx), School of Applied Sciences, University of Campinas (UNICAMP), Limeira, São Paulo 13484-350, Brazil; (K.C.C.R.); (L.P.d.M.); (J.R.P.); (D.E.C.); (E.R.R.)
| | - José R. Pauli
- Laboratory of Molecular Biology of Exercise (LaBMEx), School of Applied Sciences, University of Campinas (UNICAMP), Limeira, São Paulo 13484-350, Brazil; (K.C.C.R.); (L.P.d.M.); (J.R.P.); (D.E.C.); (E.R.R.)
| | - Dennys E. Cintra
- Laboratory of Molecular Biology of Exercise (LaBMEx), School of Applied Sciences, University of Campinas (UNICAMP), Limeira, São Paulo 13484-350, Brazil; (K.C.C.R.); (L.P.d.M.); (J.R.P.); (D.E.C.); (E.R.R.)
| | - Eduardo R. Ropelle
- Laboratory of Molecular Biology of Exercise (LaBMEx), School of Applied Sciences, University of Campinas (UNICAMP), Limeira, São Paulo 13484-350, Brazil; (K.C.C.R.); (L.P.d.M.); (J.R.P.); (D.E.C.); (E.R.R.)
| | - Ellen C. de Freitas
- Postgraduate Program in Nutritional Science, State University of São Paulo Júlio de Mesquita Filho (Araraquara). Araraquara, São Paulo 14800-903, Brazil; (T.S.V.); (G.B.); (E.C.d.F.)
- School of Physical Education and Sport of Ribeirão Preto, University of São Paulo (USP), Ribeirão Preto, São Paulo 14040-907, Brazil;
| | - Adelino S. R. da Silva
- Postgraduate Program in Rehabilitation and Functional Performance, Ribeirão Preto Medical School, University of São Paulo (USP), Ribeirão Preto, São Paulo 14049-900, Brazil; (A.P.P.); (A.L.d.R.); (E.B.K.)
- School of Physical Education and Sport of Ribeirão Preto, University of São Paulo (USP), Ribeirão Preto, São Paulo 14040-907, Brazil;
- Correspondence: ; Tel.: +55-16-33150522; Fax: +55-16-33150551
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13
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Zinc Attenuates the Cytotoxicity of Some Stimuli by Reducing Endoplasmic Reticulum Stress in Hepatocytes. Int J Mol Sci 2019; 20:ijms20092192. [PMID: 31058829 PMCID: PMC6540033 DOI: 10.3390/ijms20092192] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2019] [Revised: 04/28/2019] [Accepted: 05/02/2019] [Indexed: 01/01/2023] Open
Abstract
Zinc is an essential trace element and plays critical roles in cellular integrity and biological functions. Excess copper induced both oxidative stress and endoplasmic reticulum (ER) stress in liver-derived cultured cells. Excess copper also induced impairment of autophagic flux at the step of autophagosome–lysosome fusion, as well as Mallory–Denk body (MDB)-like inclusion body formation. Zinc ameliorated excess copper-induced impairment of autophagic flux and MDB-like inclusion body formation via the maintenance of ER homeostasis. Furthermore, zinc also ameliorated free fatty acid-induced impairment of autophagic flux. These results indicate that zinc may be able to protect hepatocytes from various ER stress-related conditions.
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14
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Chi HC, Tsai CY, Tsai MM, Yeh CT, Lin KH. Molecular functions and clinical impact of thyroid hormone-triggered autophagy in liver-related diseases. J Biomed Sci 2019; 26:24. [PMID: 30849993 PMCID: PMC6407245 DOI: 10.1186/s12929-019-0517-x] [Citation(s) in RCA: 55] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2019] [Accepted: 02/26/2019] [Indexed: 02/07/2023] Open
Abstract
The liver is controlled by several metabolic hormones, including thyroid hormone, and characteristically displays high lysosomal activity as well as metabolic stress-triggered autophagy, which is stringently regulated by the levels of hormones and metabolites. Hepatic autophagy provides energy through catabolism of glucose, amino acids and free fatty acids for starved cells, facilitating the generation of new macromolecules and maintenance of the quantity and quality of cellular organelles, such as mitochondria. Dysregulation of autophagy and defective mitochondrial homeostasis contribute to hepatocyte injury and liver-related diseases, such as non-alcoholic fatty liver disease (NAFLD) and liver cancer. Thyroid hormones (TH) mediate several critical physiological processes including organ development, cell differentiation, metabolism and cell growth and maintenance. Accumulating evidence has revealed dysregulation of cellular TH activity as the underlying cause of several liver-related diseases, including alcoholic or non-alcoholic fatty liver disease and liver cancer. Data from epidemiologic, animal and clinical studies collectively support preventive functions of THs in liver-related diseases, highlighting the therapeutic potential of TH analogs. Elucidation of the molecular mechanisms and downstream targets of TH should thus facilitate the development of therapeutic strategies for a number of major public health issues. Here, we have reviewed recent studies focusing on the involvement of THs in hepatic homeostasis through induction of autophagy and their implications in liver-related diseases. Additionally, the potential underlying molecular pathways and therapeutic applications of THs in NAFLD and HCC are discussed.
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Affiliation(s)
- Hsiang-Cheng Chi
- Radiation Biology Research Center, Institute for Radiological Research, Chang Gung University/Chang Gung Memorial Hospital, Linkou, Taoyuan, Taiwan
| | - Chung-Ying Tsai
- Kidney Research Center and Department of Nephrology, Chang Gung Immunology Consortium, Chang Gung Memorial Hospital, Taoyuan, 333, Taiwan
| | - Ming-Ming Tsai
- Department of Nursing, Chang-Gung University of Science and Technology, Taoyuan, Taiwan, 333.,Department of General Surgery, Chang Gung Memorial Hospital, Chiayi, Taiwan, 613.,Research Center for Chinese Herbal Medicine, College of Human Ecology, Chang Gung University of Science and Technology , Taoyuan, Taiwan
| | - Chau-Ting Yeh
- Liver Research Center, Chang Gung Memorial Hospital, Linkou, Taoyuan, Taiwan, 333
| | - Kwang-Huei Lin
- Liver Research Center, Chang Gung Memorial Hospital, Linkou, Taoyuan, Taiwan, 333. .,Department of Biochemistry, College of Medicine, Chang-Gung University, 259 Wen-Hwa 1 Road, Taoyuan, 333, Taiwan, Republic of China. .,Research Center for Chinese Herbal Medicine, College of Human Ecology, Chang Gung University of Science and Technology , Taoyuan, Taiwan.
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15
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Bgatova NP, Bakhbaeva SA, Taskaeva YS, Makarova VV, Borodin YI. Autophagy in Hepatocytes during Distant Tumor Growth. Bull Exp Biol Med 2018; 165:390-393. [PMID: 30006876 DOI: 10.1007/s10517-018-4177-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2017] [Indexed: 12/17/2022]
Abstract
Structural changes in the liver of CBA mice were studied during the development of experimental hepatocarcinoma-29 inoculated into the hip. A decrease in the volume density of hepatocyte cytoplasm, mitochondria, endoplasmic reticulum, and lipid inclusions and an increase in the volume density of lysosomal structures during tumor growth were observed. All stages of intracellular autophagy were recorded by the method of electron microscopy. These stages included the appearance of autophagosomes, autophagolysosomes, and secondary lysosomes in the hepatocyte cytoplasm. Fragments of cytoplasm, glycogen rosettes, mitochondria, and fragments of endoplasmic reticulum with ribosomes were found in autophagosomes. The obtained data indicate the development of non-selective autophagy in the liver during distant tumor growth in aimed at the maintenance of intracellular homeostasis in hepatocytes and energy and trophic homeostasis of organism.
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Affiliation(s)
- N P Bgatova
- Research Institute of Clinical and Experimental Lymphology, Branch of the Federal Research Centre Institute of Cytology and Genetics, Siberian Division of the Russian Academy of Sciences, Novosibirsk, Russia.
| | - S A Bakhbaeva
- Research Institute of Clinical and Experimental Lymphology, Branch of the Federal Research Centre Institute of Cytology and Genetics, Siberian Division of the Russian Academy of Sciences, Novosibirsk, Russia
| | - Yu S Taskaeva
- Research Institute of Clinical and Experimental Lymphology, Branch of the Federal Research Centre Institute of Cytology and Genetics, Siberian Division of the Russian Academy of Sciences, Novosibirsk, Russia
| | - V V Makarova
- Research Institute of Clinical and Experimental Lymphology, Branch of the Federal Research Centre Institute of Cytology and Genetics, Siberian Division of the Russian Academy of Sciences, Novosibirsk, Russia
| | - Yu I Borodin
- Research Institute of Clinical and Experimental Lymphology, Branch of the Federal Research Centre Institute of Cytology and Genetics, Siberian Division of the Russian Academy of Sciences, Novosibirsk, Russia
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16
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Dethlefsen MM, Kristensen CM, Tøndering AS, Lassen SB, Ringholm S, Pilegaard H. Impact of liver PGC-1α on exercise and exercise training-induced regulation of hepatic autophagy and mitophagy in mice on HFF. Physiol Rep 2018; 6:e13731. [PMID: 29962089 PMCID: PMC6026591 DOI: 10.14814/phy2.13731] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2018] [Revised: 05/07/2018] [Accepted: 05/08/2018] [Indexed: 01/01/2023] Open
Abstract
Hepatic autophagy has been shown to be regulated by acute exercise and exercise training. Moreover, high-fat diet-induced steatosis has been reported to be associated with impaired hepatic autophagy. In addition, autophagy has been shown to be regulated by acute exercise and exercise training in a PGC-1α dependent manner in skeletal muscle. The aim of this study was to test the hypotheses that high-fat high-fructose (HFF) diet changes hepatic autophagy and mitophagy, that exercise training can restore this through a PGC-1α-mediated mechanism, and that acute exercise regulates autophagy and mitophagy in the liver. Liver samples were obtained from liver-specific PGC-1α KO mice and their littermate Lox/Lox mice fed a HFF diet or a control diet for 13 weeks. The HFF mice were either exercise trained (ExT) on a treadmill the final 5 weeks or remained sedentary (UT). In addition, half of each group performed at the end of the intervention an acute 1 h exercise bout. HFF resulted in increased hepatic BNIP3 dimer and Parkin protein, while exercise training increased BNIP3 total protein without affecting the elevated BNIP3 dimer protein. In addition, exercise training reversed a HFF-induced increase in hepatic LC3II/LC3I protein ratio, as well as a decreased PGC-1α mRNA level. Acute exercise increased hepatic PGC-1α mRNA in HFF UT mice only. In conclusion, this indicates that exercise training in part reverses a HFF-induced increase in hepatic autophagy and capacity for mitophagy in a PGC-1α-independent manner. Moreover, HFF may blunt acute exercise-induced regulation of hepatic autophagy.
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Affiliation(s)
- Maja M. Dethlefsen
- Department of BiologySection for Cell Biology and PhysiologyUniversity of CopenhagenKobenhavnDenmark
| | - Caroline M. Kristensen
- Department of BiologySection for Cell Biology and PhysiologyUniversity of CopenhagenKobenhavnDenmark
| | - Anna S. Tøndering
- Department of BiologySection for Cell Biology and PhysiologyUniversity of CopenhagenKobenhavnDenmark
| | - Signe B. Lassen
- Department of BiologySection for Cell Biology and PhysiologyUniversity of CopenhagenKobenhavnDenmark
| | - Stine Ringholm
- Department of BiologySection for Cell Biology and PhysiologyUniversity of CopenhagenKobenhavnDenmark
| | - Henriette Pilegaard
- Department of BiologySection for Cell Biology and PhysiologyUniversity of CopenhagenKobenhavnDenmark
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17
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Masyuk TV, Masyuk AI, LaRusso NF. Therapeutic Targets in Polycystic Liver Disease. Curr Drug Targets 2018; 18:950-957. [PMID: 25915482 DOI: 10.2174/1389450116666150427161743] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2015] [Revised: 02/06/2015] [Accepted: 03/02/2015] [Indexed: 02/06/2023]
Abstract
Polycystic liver diseases (PLD) are a group of genetic disorders initiated by mutations in several PLD-related genes and characterized by the presence of multiple cholangiocyte-derived hepatic cysts that progressively replace liver tissue. PLD co-exists with Autosomal Dominant Polycystic Kidney Disease (ADPKD) and Autosomal Recessive PKD as well as occurs alone (i.e., Autosomal Dominant Polycystic Liver Disease [ADPLD]). PLD associated with ADPKD and ARPKD belong to a group of disorders known as cholangiociliopathies since many disease-causative and disease-related proteins are expressed in primary cilia of cholangiocytes. Aberrant expression of these proteins in primary cilia affects their structures and functions promoting cystogenesis. Current medical therapies for PLD include symptomatic management and surgical interventions. To date, the only available drug treatment for PLD patients that halt disease progression and improve quality of life are somatostatin analogs. However, the modest clinical benefits, need for long-term maintenance therapy, and the high cost of treatment justify the necessity for more effective treatment options. Substantial evidence suggests that experimental manipulations with components of the signaling pathways that influence cyst development (e.g., cAMP, intracellular calcium, receptor tyrosine kinase, transient receptor potential cation channel subfamily V member 4 (TRPV4) channel, mechanistic target of rapamycin (mTOR), histone deacetylase (HDAC6), Cdc25A phosphatase, miRNAs and metalloproteinases) attenuate growth of hepatic cysts. Many of these targets have been evaluated in pre-clinical trials suggesting their value as potential new therapies. This review outlines the current clinical and preclinical treatment strategies for PLD.
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Affiliation(s)
- Tatyana V Masyuk
- Division of Gastroenterology and Hepatology, Mayo Clinic, Rochester, MN, United States
| | - Anatoliy I Masyuk
- Division of Gastroenterology and Hepatology, Mayo Clinic, Rochester, MN, United States
| | - Nicholas F LaRusso
- Division of Gastroenterology and Hepatology, Mayo Clinic College of Medicine, 200 First Street, SW Rochester, Minnesota, MN 55905, United States
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18
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Qian Q, Zhang Z, Orwig A, Chen S, Ding WX, Xu Y, Kunz RC, Lind NRL, Stamler JS, Yang L. S-Nitrosoglutathione Reductase Dysfunction Contributes to Obesity-Associated Hepatic Insulin Resistance via Regulating Autophagy. Diabetes 2018; 67:193-207. [PMID: 29074597 PMCID: PMC10515702 DOI: 10.2337/db17-0223] [Citation(s) in RCA: 51] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/13/2017] [Accepted: 10/20/2017] [Indexed: 11/13/2022]
Abstract
Obesity is associated with elevated intracellular nitric oxide (NO) production, which promotes nitrosative stress in metabolic tissues such as liver and skeletal muscle, contributing to insulin resistance. The onset of obesity-associated insulin resistance is due, in part, to the compromise of hepatic autophagy, a process that leads to lysosomal degradation of cellular components. However, it is not known how NO bioactivity might impact autophagy in obesity. Here, we establish that S-nitrosoglutathione reductase (GSNOR), a major protein denitrosylase, provides a key regulatory link between inflammation and autophagy, which is disrupted in obesity and diabetes. We demonstrate that obesity promotes S-nitrosylation of lysosomal proteins in the liver, thereby impairing lysosomal enzyme activities. Moreover, in mice and humans, obesity and diabetes are accompanied by decreases in GSNOR activity, engendering nitrosative stress. In mice with a GSNOR deletion, diet-induced obesity increases lysosomal nitrosative stress and impairs autophagy in the liver, leading to hepatic insulin resistance. Conversely, liver-specific overexpression of GSNOR in obese mice markedly enhances lysosomal function and autophagy and, remarkably, improves insulin action and glucose homeostasis. Furthermore, overexpression of S-nitrosylation-resistant variants of lysosomal enzymes enhances autophagy, and pharmacologically and genetically enhancing autophagy improves hepatic insulin sensitivity in GSNOR-deficient hepatocytes. Taken together, our data indicate that obesity-induced protein S-nitrosylation is a key mechanism compromising the hepatic autophagy, contributing to hepatic insulin resistance.
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Affiliation(s)
- Qingwen Qian
- Department of Anatomy and Cell Biology, Fraternal Order of Eagles Diabetes Research Center, The Pappajohn Biomedical Institute, Carver College of Medicine, University of Iowa, Iowa City, IA
| | - Zeyuan Zhang
- Department of Anatomy and Cell Biology, Fraternal Order of Eagles Diabetes Research Center, The Pappajohn Biomedical Institute, Carver College of Medicine, University of Iowa, Iowa City, IA
| | - Allyson Orwig
- Department of Anatomy and Cell Biology, Fraternal Order of Eagles Diabetes Research Center, The Pappajohn Biomedical Institute, Carver College of Medicine, University of Iowa, Iowa City, IA
| | - Songhai Chen
- Department of Pharmacology, Carver College of Medicine, University of Iowa, Iowa City, IA
| | - Wen-Xing Ding
- Department of Pharmacology, Toxicology and Therapeutics, University of Kansas Medical Center, Kansas City, KS
| | - Yanji Xu
- Shaun and Lilly International, LLC, Collierville, TN
| | - Ryan C Kunz
- Thermo Fisher Scientific Center for Multiplexed Proteomics, Harvard Medical School, Boston, MA
| | - Nicholas R L Lind
- Department of Anatomy and Cell Biology, Fraternal Order of Eagles Diabetes Research Center, The Pappajohn Biomedical Institute, Carver College of Medicine, University of Iowa, Iowa City, IA
| | - Jonathan S Stamler
- Institute for Transformative Molecular Medicine and Department of Medicine, Case Western Reserve University and Harrington Discovery Institute, University Hospitals, Cleveland, OH
| | - Ling Yang
- Department of Anatomy and Cell Biology, Fraternal Order of Eagles Diabetes Research Center, The Pappajohn Biomedical Institute, Carver College of Medicine, University of Iowa, Iowa City, IA
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19
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Calcium-dependent O-GlcNAc signaling drives liver autophagy in adaptation to starvation. Genes Dev 2017; 31:1655-1665. [PMID: 28903979 PMCID: PMC5647936 DOI: 10.1101/gad.305441.117] [Citation(s) in RCA: 98] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2016] [Accepted: 08/14/2017] [Indexed: 12/19/2022]
Abstract
In this study, Ruan et al. demonstrate that O-GlcNAc transferase (OGT) is required for glucagon-stimulated liver autophagy and metabolic adaptation to starvation. Their findings delineate a new signaling pathway in which starvation promotes autophagy through OGT phosphorylation and establish the importance of O-GlcNAc signaling in coupling liver autophagy to nutrient homeostasis. Starvation induces liver autophagy, which is thought to provide nutrients for use by other organs and thereby maintain whole-body homeostasis. Here we demonstrate that O-linked β-N-acetylglucosamine (O-GlcNAc) transferase (OGT) is required for glucagon-stimulated liver autophagy and metabolic adaptation to starvation. Genetic ablation of OGT in mouse livers reduces autophagic flux and the production of glucose and ketone bodies. Upon glucagon-induced calcium signaling, calcium/calmodulin-dependent kinase II (CaMKII) phosphorylates OGT, which in turn promotes O-GlcNAc modification and activation of Ulk proteins by potentiating AMPK-dependent phosphorylation. These findings uncover a signaling cascade by which starvation promotes autophagy through OGT phosphorylation and establish the importance of O-GlcNAc signaling in coupling liver autophagy to nutrient homeostasis.
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20
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Wang R, Shen Z, Yang L, Yin M, Zheng W, Wu B, Liu T, Song H. Protective effects of heme oxygenase-1-transduced bone marrow-derived mesenchymal stem cells on reduced‑size liver transplantation: Role of autophagy regulated by the ERK/mTOR signaling pathway. Int J Mol Med 2017; 40:1537-1548. [PMID: 28901391 PMCID: PMC5627878 DOI: 10.3892/ijmm.2017.3121] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2017] [Accepted: 08/21/2017] [Indexed: 12/17/2022] Open
Abstract
Autophagy is a critical lysosomal pathway that degrades cytoplasmic components to maintain cell homeostasis and provide substrates for energy metabolism. A study revealed that heme oxygenase-1 (HO-1)-transduced bone marrow-derived mesenchymal stem cells (BM-MSCs) could protect 50% reduced-size liver transplantation (RSLT) in a rat model. However, the mechanisms remain mostly unknown. The aim of the present study was to explore the effects and related mechanism of autophagy on the protection conferred by HO-1-transduced BM-MSCs (HO-1/BM-MSCs) on 50% RSLT in a rat model. The authors established an acute rejection model following 50% RSLT in rats, with recipients divided into three groups receiving treatment with BM-MSCs, HO-1/BM-MSCs or normal saline (NS) injected through the dorsal penile vein. Transplanted liver tissues at 0, 1, 3, 5, 7, 10 and 14 days following transplantation were acquired for further analysis. The results indicated that the expression of autophagy-related proteins LC3 and Beclin-1 increased, the levels of ERK and p-ERK increased, and the levels of mammalian target of rapamycin (mTOR) and p-mTOR decreased in the HO-1/BM-MSCs. These observations indicated that autophagy is involved in the protective effects of HO-1/BM-MSCs on liver grafts following RSLT, possibly via upregulation of autophagy-related proteins through the ERK/mTOR signaling pathway.
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Affiliation(s)
- Raorao Wang
- Tianjin First Central Hospital Clinic Institute, Tianjin Medical University, Tianjin 300070, P.R. China
| | - Zhongyang Shen
- Department of Organ Transplantation, Tianjin First Central Hospital, Tianjin 300192, P.R. China
| | - Liu Yang
- Tianjin First Central Hospital Clinic Institute, Tianjin Medical University, Tianjin 300070, P.R. China
| | - Mingli Yin
- Tianjin First Central Hospital Clinic Institute, Tianjin Medical University, Tianjin 300070, P.R. China
| | - Weiping Zheng
- Department of Organ Transplantation, Tianjin First Central Hospital, Tianjin 300192, P.R. China
| | - Bin Wu
- Department of Organ Transplantation, Tianjin First Central Hospital, Tianjin 300192, P.R. China
| | - Tao Liu
- Department of Organ Transplantation, Tianjin First Central Hospital, Tianjin 300192, P.R. China
| | - Hongli Song
- Department of Organ Transplantation, Tianjin First Central Hospital, Tianjin 300192, P.R. China
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ER Stress and Autophagy in Obesity and Nonalcoholic Fatty Liver Disease. CURRENT PATHOBIOLOGY REPORTS 2017. [DOI: 10.1007/s40139-017-0145-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Li R, Guo E, Yang J, Li A, Yang Y, Liu S, Liu A, Jiang X. 1,25(OH) 2 D 3 attenuates hepatic steatosis by inducing autophagy in mice. Obesity (Silver Spring) 2017; 25:561-571. [PMID: 28145056 DOI: 10.1002/oby.21757] [Citation(s) in RCA: 58] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/06/2016] [Revised: 11/22/2016] [Accepted: 12/03/2016] [Indexed: 01/10/2023]
Abstract
OBJECTIVE 1,25(OH)2 D3 has been reported to attenuate liver steatosis; however, its exact mechanism of action remains poorly understood. This study aimed to determine whether 1,25(OH)2 D3 can attenuate hepatic steatosis by inducing autophagy. METHODS Male C57BL/6 mice fed a high-fat diet (HFD) were injected with 1,25(OH)2 D3 for 4 weeks. These mice were given 3-methyladenine (3-MA) to inhibit autophagy. HepG2 cells were preincubated with a free fatty acid (FFA) and then treated with 1,25(OH)2 D3 . Vitamin D receptor (VDR) shRNA and autophagy-related 16-like 1 (ATG16L1) siRNA were used for VDR knockdown or ATG16L1 silencing, respectively. RESULTS 1,25(OH)2 D3 diminished HFD-induced liver damage and steatosis, changes accompanied by autophagy and ATG16L1 expression upregulation. Inhibition of 1,25(OH)2 D3 -induced autophagy mediated by 3-MA blocked the protective effects of 1,25(OH)2 D3 on hepatic steatosis. Additionally, 1,25(OH)2 D3 -induced autophagy appeared to play a role in anti-inflammation and lipid metabolism modulation in the liver. In HepG2 cells, 1,25(OH)2 D3 reduced lipid accumulation and increased autophagy and ATG16L1 expression; however, this effect was abrogated after VDR knockdown. The protective effects of 1,25(OH)2 D3 -mediated autophagy against lipid accumulation were abolished by 3-MA. Furthermore, siRNA-mediated ATG16L1 knockdown prevented 1,25(OH)2 D3 -induced autophagy, resulting in increased fat accumulation. CONCLUSIONS The data suggest that 1,25(OH)2 D3 may ameliorate hepatic steatosis by inducing autophagy by upregulating ATG16L1.
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Affiliation(s)
- Renlong Li
- Graduate School, Southern Medical University, Guangzhou, China
- Department of Infectious Diseases, Wuhan General Hospital of Guangzhou Military Command, Wuhan, China
| | - Enshuang Guo
- Graduate School, Southern Medical University, Guangzhou, China
- Department of Infectious Diseases, Wuhan General Hospital of Guangzhou Military Command, Wuhan, China
| | - Jiankun Yang
- Experimental Medicine Center, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Anyi Li
- Animal Experimental Center, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Yan Yang
- Experimental Medicine Center, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Shenpei Liu
- Experimental Medicine Center, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Anding Liu
- Experimental Medicine Center, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Xiaojing Jiang
- Graduate School, Southern Medical University, Guangzhou, China
- Department of Infectious Diseases, Wuhan General Hospital of Guangzhou Military Command, Wuhan, China
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Chi HC, Chen SL, Tsai CY, Chuang WY, Huang YH, Tsai MM, Wu SM, Sun CP, Yeh CT, Lin KH. Thyroid hormone suppresses hepatocarcinogenesis via DAPK2 and SQSTM1-dependent selective autophagy. Autophagy 2016; 12:2271-2285. [PMID: 27653365 DOI: 10.1080/15548627.2016.1230583] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Recent studies have demonstrated a critical association between disruption of cellular thyroid hormone (TH) signaling and the incidence of hepatocellular carcinoma (HCC), but the underlying mechanisms remain largely elusive. Here, we showed that disruption of TH production results in a marked increase in progression of diethylnitrosamine (DEN)-induced HCC in a murine model, and conversely, TH administration suppresses the carcinogenic process via activation of autophagy. Inhibition of autophagy via treatment with chloroquine (CQ) or knockdown of ATG7 (autophagy-related 7) via adeno-associated virus (AAV) vectors, suppressed the protective effects of TH against DEN-induced hepatic damage and development of HCC. The involvement of autophagy in TH-mediated protection was further supported by data showing transcriptional activation of DAPK2 (death-associated protein kinase 2; a serine/threonine protein kinase), which enhanced the phosphorylation of SQSTM1/p62 (sequestosome 1) to promote selective autophagic clearance of protein aggregates. Ectopic expression of DAPK2 further attenuated DEN-induced hepatoxicity and DNA damage though enhanced autophagy, whereas, knockdown of DAPK2 displayed the opposite effect. The pathological significance of the TH-mediated hepatoprotective effect by DAPK2 was confirmed by the concomitant decrease in the expression of THRs and DAPK2 in matched HCC tumor tissues. Taken together, these findings indicate that TH promotes selective autophagy via induction of DAPK2-SQSTM1 cascade, which in turn protects hepatocytes from DEN-induced hepatotoxicity or carcinogenesis.
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Affiliation(s)
- Hsiang-Cheng Chi
- a Department of Biochemistry , College of Medicine, Chang-Gung University , Taoyuan , Taiwan
| | - Shen-Liang Chen
- b Department of Life Sciences , National Central University , Jhongli , Taiwan
| | - Chung-Ying Tsai
- a Department of Biochemistry , College of Medicine, Chang-Gung University , Taoyuan , Taiwan
| | - Wen-Yu Chuang
- c Department of Pathology , Chang Gung Memorial Hospital and Chang Gung University College of Medicine , Taoyuan , Taiwan
| | - Ya-Hui Huang
- d Liver Research Center, Chang Gung Memorial Hospital , Linkou, Taoyuan , Taiwan
| | - Ming-Ming Tsai
- e Department of Nursing , Chang-Gung University of Science and Technology , Taoyuan , Taiwan.,f Department of General Surgery , Chang Gung Memorial Hospital at Chiayi , Taiwan
| | - Sheng-Ming Wu
- a Department of Biochemistry , College of Medicine, Chang-Gung University , Taoyuan , Taiwan.,g Division of Pulmonary Medicine, Department of Internal Medicine , Shuang Ho Hospital, Taipei Medical University
| | - Cheng-Pu Sun
- h Institute of Biomedical Sciences, Academia Sinica , Taipei , Taiwan
| | - Chau-Ting Yeh
- d Liver Research Center, Chang Gung Memorial Hospital , Linkou, Taoyuan , Taiwan
| | - Kwang-Huei Lin
- a Department of Biochemistry , College of Medicine, Chang-Gung University , Taoyuan , Taiwan.,d Liver Research Center, Chang Gung Memorial Hospital , Linkou, Taoyuan , Taiwan
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Novel Grb14-Mediated Cross Talk between Insulin and p62/Nrf2 Pathways Regulates Liver Lipogenesis and Selective Insulin Resistance. Mol Cell Biol 2016; 36:2168-81. [PMID: 27215388 DOI: 10.1128/mcb.00170-16] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2016] [Accepted: 05/17/2016] [Indexed: 12/24/2022] Open
Abstract
A long-standing paradox in the pathophysiology of metabolic diseases is the selective insulin resistance of the liver. It is characterized by a blunted action of insulin to reduce glucose production, contributing to hyperglycemia, while de novo lipogenesis remains insulin sensitive, participating in turn to hepatic steatosis onset. The underlying molecular bases of this conundrum are not yet fully understood. Here, we established a model of selective insulin resistance in mice by silencing an inhibitor of insulin receptor catalytic activity, the growth factor receptor binding protein 14 (Grb14) in liver. Indeed, Grb14 knockdown enhanced hepatic insulin signaling but also dramatically inhibited de novo fatty acid synthesis. In the liver of obese and insulin-resistant mice, downregulation of Grb14 markedly decreased blood glucose and improved liver steatosis. Mechanistic analyses showed that upon Grb14 knockdown, the release of p62/sqstm1, a partner of Grb14, activated the transcription factor nuclear factor erythroid-2-related factor 2 (Nrf2), which in turn repressed the lipogenic nuclear liver X receptor (LXR). Our study reveals that Grb14 acts as a new signaling node that regulates lipogenesis and modulates insulin sensitivity in the liver by acting at a crossroad between the insulin receptor and the p62-Nrf2-LXR signaling pathways.
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25
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Masouminia M, Samadzadeh S, Mendoza AS, French BA, Tillman B, French SW. Upregulation of autophagy components in alcoholic hepatitis and nonalcoholic steatohepatitis. Exp Mol Pathol 2016; 101:81-8. [PMID: 27432584 DOI: 10.1016/j.yexmp.2016.07.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2016] [Accepted: 07/14/2016] [Indexed: 02/07/2023]
Abstract
There are many homeostatic mechanisms for coping with stress conditions in cells, including autophagy. In many studies autophagy, as an intracellular pathway which degrades misfolded and damaged protein, and Mallory-Denk Body (MDB) formation have been shown to be protective mechanisms against stress such as alcoholic hepatitis. Alcohol has a significant role in alteration of lipid homeostasis, sterol regulatory element-binding proteins (SREBPs) and peroxidase proliferator-activated receptors through AMP-activated protein kinase (AMPK)-dependent mechanism. AMPK is one of the kinases that regulate autophagy through the dephosphorylation of ATG1. Activation of ATG1 (ULK kinases family) activates ATG6. These two activated proteins relocate to the site of initial autophagosome and activate the other downstream components of autophagocytosis. Many other proteins regulate autophagocytosis at the gene level. CHOP (C/EBP homologous protein) is one of the most important parts of stress-inducible transcription that encodes a ubiquitous transcription factor. In this report we measure the upregulation of the gene that are involved in autophagocytosis in liver biopsies of alcoholic hepatitis and NASH. Electron microscopy was used to document the presence of autophagosomes in the liver cells. Expression of AMPK1, ATG1, ATG6 and CHOP in ASH were significantly (p value<0.05) upregulated in comparison to control. Electron microscopy findings of ASH confirmed the presence of autophagosomes, one of which contained a MDB, heretofore undescribed. Significant upregulations of AMPK-1, ATG-1, ATG-6, and CHOP, and uptrending of ATG-4, ATG-5, ATG-9, ATR, and ATM in ASH compared to normal control livers indicate active autophagocytosis in alcoholic hepatitis.
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Affiliation(s)
- M Masouminia
- Harbor UCLA Medical Center, Department of Pathology, Torrance, CA, United States
| | | | - A S Mendoza
- Harbor UCLA Medical Center, Department of Pathology, Torrance, CA, United States
| | | | - B Tillman
- LA Biomed, Torrance, CA, United States
| | - S W French
- Harbor UCLA Medical Center, Department of Pathology, Torrance, CA, United States.
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26
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Unuma K, Aki T, Funakoshi T, Hashimoto K, Uemura K. Extrusion of mitochondrial contents from lipopolysaccharide-stimulated cells: Involvement of autophagy. Autophagy 2016; 11:1520-36. [PMID: 26102061 DOI: 10.1080/15548627.2015.1063765] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Sepsis/endotoxemia is elicited by the circulatory distribution of pathogens/endotoxins into whole bodies, and causes profound effects on human health by causing inflammation in multiple organs. Mitochondrial damage is one of the characteristics of the cellular degeneration observed during sepsis/endotoxemia. Elimination of damaged mitochondria through the autophagy-lysosome system has been reported in the liver, indicating that autophagy should play an important role in liver homeostasis during sepsis/endotoxemia. An increased appearance of mitochondrial DNA and proteins in the plasma is another feature of sepsis/endotoxemia, suggesting that damaged mitochondria are not only eliminated within the cells, but also extruded through currently unknown mechanisms. Here we provide evidence for the secretion of mitochondrial proteins and DNA from lipopolysaccharide (LPS)-stimulated rat hepatocytes as well as mouse embryonic fibroblasts (MEFs). The secretion of mitochondrial contents is accompanied by the secretion of proteins that reside in the lumenal space of autolysosomes (LC3-II and CTSD/cathepsin D), but not by a lysosomal membrane protein (LAMP1). The pharmacological inhibition of autophagy by 3MA blocks the secretion of mitochondrial constituents from LPS-stimulated hepatocytes. LPS also stimulates the secretion of mitochondrial as well as autolysosomal lumenal proteins from wild-type (Atg5(+/+)) MEFs, but not from atg5(-/-) MEFs. Furthermore, we show that direct exposure of purified mitochondria activates polymorphonuclear leukocytes (PMNs), as evident by the induction of IL1B/interlekin-1β, a pro-inflammatory cytokine. Taken together, the data suggest the active extrusion of mitochondrial contents, which provoke an inflammatory response of immune cells, through the exocytosis of autolysosomes by cells stimulated with LPS.
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Affiliation(s)
- Kana Unuma
- a Department of Forensic Medicine ; Graduate School of Medical and Dental Sciences; Tokyo Medical and Dental University ; Tokyo , Japan
| | - Toshihiko Aki
- a Department of Forensic Medicine ; Graduate School of Medical and Dental Sciences; Tokyo Medical and Dental University ; Tokyo , Japan
| | - Takeshi Funakoshi
- a Department of Forensic Medicine ; Graduate School of Medical and Dental Sciences; Tokyo Medical and Dental University ; Tokyo , Japan
| | - Kyoko Hashimoto
- a Department of Forensic Medicine ; Graduate School of Medical and Dental Sciences; Tokyo Medical and Dental University ; Tokyo , Japan
| | - Koichi Uemura
- a Department of Forensic Medicine ; Graduate School of Medical and Dental Sciences; Tokyo Medical and Dental University ; Tokyo , Japan
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27
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Kim SM, Wang Y, Nabavi N, Liu Y, Correia MA. Hepatic cytochromes P450: structural degrons and barcodes, posttranslational modifications and cellular adapters in the ERAD-endgame. Drug Metab Rev 2016; 48:405-33. [PMID: 27320797 DOI: 10.1080/03602532.2016.1195403] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The endoplasmic reticulum (ER)-anchored hepatic cytochromes P450 (P450s) are enzymes that metabolize endo- and xenobiotics i.e. drugs, carcinogens, toxins, natural and chemical products. These agents modulate liver P450 content through increased synthesis or reduction via inactivation and/or proteolytic degradation, resulting in clinically significant drug-drug interactions. P450 proteolytic degradation occurs via ER-associated degradation (ERAD) involving either of two distinct routes: Ubiquitin (Ub)-dependent 26S proteasomal degradation (ERAD/UPD) or autophagic lysosomal degradation (ERAD/ALD). CYP3A4, the major human liver/intestinal P450, and the fast-turnover CYP2E1 species are degraded via ERAD/UPD entailing multisite protein phosphorylation and subsequent ubiquitination by gp78 and CHIP E3 Ub-ligases. We are gaining insight into the nature of the structural determinants involved in CYP3A4 and CYP2E1 molecular recognition in ERAD/UPD [i.e. K48-linked polyUb chains and linear and/or "conformational" phosphodegrons consisting either of consecutive sequences on surface loops and/or disordered regions, or structurally-assembled surface clusters of negatively charged acidic (Asp/Glu) and phosphorylated (Ser/Thr) residues, within or vicinal to which, Lys-residues are targeted for ubiquitination]. Structural inspection of select human liver P450s reveals that such linear or conformational phosphodegrons may indeed be a common P450-ERAD/UPD feature. By contrast, although many P450s such as the slow-turnover CYP2E1 species and rat liver CYP2B1 and CYP2C11 are degraded via ERAD/ALD, little is known about the mechanism of their ALD-targeting. On the basis of our current knowledge of ALD-substrate targeting, we propose a tripartite conjunction of K63-linked Ub-chains, P450 structural "LIR" motifs and selective cellular "cargo receptors" as plausible P450-ALD determinants.
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Affiliation(s)
- Sung-Mi Kim
- a Department of Cellular & Molecular Pharmacology , University of California San Francisco , San Francisco , CA , USA
| | - YongQiang Wang
- a Department of Cellular & Molecular Pharmacology , University of California San Francisco , San Francisco , CA , USA
| | - Noushin Nabavi
- a Department of Cellular & Molecular Pharmacology , University of California San Francisco , San Francisco , CA , USA
| | - Yi Liu
- a Department of Cellular & Molecular Pharmacology , University of California San Francisco , San Francisco , CA , USA
| | - Maria Almira Correia
- a Department of Cellular & Molecular Pharmacology , University of California San Francisco , San Francisco , CA , USA ;,b Department of Pharmaceutical Chemistry , University of California San Francisco , San Francisco , CA , USA ;,c Department of Bioengineering and Therapeutic Sciences , University of California San Francisco , San Francisco , CA , USA ;,d The Liver Center, University of California San Francisco , San Francisco , CA , USA
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Miyagawa K, Oe S, Honma Y, Izumi H, Baba R, Harada M. Lipid-Induced Endoplasmic Reticulum Stress Impairs Selective Autophagy at the Step of Autophagosome-Lysosome Fusion in Hepatocytes. THE AMERICAN JOURNAL OF PATHOLOGY 2016; 186:1861-1873. [PMID: 27157992 DOI: 10.1016/j.ajpath.2016.03.003] [Citation(s) in RCA: 67] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Received: 10/30/2015] [Revised: 02/18/2016] [Accepted: 03/04/2016] [Indexed: 02/08/2023]
Abstract
Blockage of hepatic autophagic degradation system occurs in obesity and is associated with the development of nonalcoholic fatty liver disease. However, the mechanism of this blockage remains unclear. We found a high-fat diet induced accumulation of autophagosomes in the mice livers. However, autophagy substrates such as p62 and ubiquitinated proteins also accumulated in the livers in this model. These findings indicate the possibility that a high-fat diet impairs autophagic flux in the liver. Then, to assess the autophagic flux in more detail, we performed analyses of autophagic flux in cultured hepatocytes exposed to monounsaturated fatty acids (FAs) or saturated FAs (SFAs). SFAs but not monounsaturated FAs suppressed degradation of contents in the autophagosomes. We analyzed each stage of the autophagy pathway (ie, autophagosome formation, autophagosome-lysosome fusion, lysosomal degradation) in cultured hepatocytes treated with monounsaturated FAs or SFAs and found that SFAs impaired autophagosome-lysosome fusion. This impairment occurred in an endoplasmic reticulum stress-dependent manner. Moreover, ubiquitin and p62-positive inclusions observed in high-fat diet-fed mice livers and SFA-treated cells were sequestered within autophagosomes. We also found that SFA-induced accumulation of Ser351-phosphorylated p62, which is indispensable for selective autophagy, further increased on administration of a lysosomal proteinase inhibitor. Although lipid-induced endoplasmic reticulum stress interferes with the autophagosome-lysosome fusion, selective autophagic sequestration of aggregated proteins is not inhibited.
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Affiliation(s)
- Koichiro Miyagawa
- Third Department of Internal Medicine, School of Medicine, University of Occupational and Environmental Health, Kitakyushu, Japan.
| | - Shinji Oe
- Third Department of Internal Medicine, School of Medicine, University of Occupational and Environmental Health, Kitakyushu, Japan
| | - Yuichi Honma
- Third Department of Internal Medicine, School of Medicine, University of Occupational and Environmental Health, Kitakyushu, Japan
| | - Hiroto Izumi
- Department of Occupational Pneumology, School of Medicine, University of Occupational and Environmental Health, Kitakyushu, Japan
| | - Ryoko Baba
- Department of Anatomy, School of Medicine, University of Occupational and Environmental Health, Kitakyushu, Japan
| | - Masaru Harada
- Third Department of Internal Medicine, School of Medicine, University of Occupational and Environmental Health, Kitakyushu, Japan.
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Wree A, Mehal WZ, Feldstein AE. Targeting Cell Death and Sterile Inflammation Loop for the Treatment of Nonalcoholic Steatohepatitis. Semin Liver Dis 2016; 36:27-36. [PMID: 26870930 PMCID: PMC4955833 DOI: 10.1055/s-0035-1571272] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Nonalcoholic fatty liver disease represents a wide spectrum of conditions and is currently the most common form of chronic liver disease affecting both adults and children in the United States and many other parts of the world. Great effort has been focused on the development of novel therapies for those patients with the more advanced forms of the disease, in particular those with nonalcoholic steatohepatitis (NASH) and liver fibrosis that can be associated with significant morbidity and mortality. In this review, the authors focus on the role of cell death and sterile inflammatory pathways as well as the self-perpetuating deleterious cycle they may trigger as novel therapeutic targets for the treatment of fibrotic NASH.
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Affiliation(s)
- Alexander Wree
- Department of Pediatrics, University of California San Diego (UCSD), and Rady Children’s Hospital, San Diego, California,Department of Internal Medicine III, University Hospital, RWTH-Aachen, Germany
| | - Wajahat Z. Mehal
- Yale University, and West Haven Veterans Medical Center, New Haven, Connecticut
| | - Ariel E. Feldstein
- Department of Pediatrics, University of California San Diego (UCSD), and Rady Children’s Hospital, San Diego, California
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Abstract
Excessive ethanol exposure is detrimental to the brain. The developing brain is particularly vulnerable to ethanol such that prenatal ethanol exposure causes fetal alcohol spectrum disorders (FASD). Neuronal loss in the brain is the most devastating consequence and is associated with mental retardation and other behavioral deficits observed in FASD. Since alcohol consumption during pregnancy has not declined, it is imperative to elucidate the underlying mechanisms and develop effective therapeutic strategies. One cellular mechanism that acts as a protective response for the central nervous system (CNS) is autophagy. Autophagy regulates lysosomal turnover of organelles and proteins within cells, and is involved in cell differentiation, survival, metabolism, and immunity. We have recently shown that ethanol activates autophagy in the developing brain. The autophagic preconditioning alleviates ethanol-induced neuron apoptosis, whereas inhibition of autophagy potentiates ethanol-stimulated reactive oxygen species (ROS) and exacerbates ethanol-induced neuroapoptosis. The expression of genes encoding proteins required for autophagy in the CNS is developmentally regulated; their levels are much lower during an ethanol-sensitive period than during an ethanol-resistant period. Ethanol may stimulate autophagy through multiple mechanisms; these include induction of oxidative stress and endoplasmic reticulum stress, modulation of MTOR and AMPK signaling, alterations in BCL2 family proteins, and disruption of intracellular calcium (Ca2+) homeostasis. This review discusses the most recent evidence regarding the involvement of autophagy in ethanol-mediated neurotoxicity as well as the potential therapeutic approach of targeting autophagic pathways.
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Key Words
- AD, Alzheimer disease
- ALS, autophagy-lysosome system
- AMPK, adenosine 5′-monophosphate-activated protein kinase;
- ATG, autophagy-related
- CNS, central nervous system
- ER, endoplasmic reticulum
- FASD, fetal alcohol spectrum disorders
- FOXO3, forkhead box O3
- GSK3B, glycogen synthase kinase 3 β
- HD, Huntington disease, HNSCs, hippocampal neural stem cells
- LC3, microtubule-associated protein 1 light chain 3
- MTOR, mechanistic target of rapamycin (serine/threonine kinase)
- MTORC1, MTOR complex 1
- NFE2L2, nuclear factor, erythroid 2-like 2
- NOX, NADPH oxidase
- PD, Parkinson disease
- PI3K, class I phosphoinositide 3-kinase
- ROS, reactive oxygen species
- SQSTM1/p62, sequestosome 1
- TSC1/2, tuberous sclerosis 1/ 2
- UPR, unfolded protein response
- alcohol
- alcoholism
- development
- fetal alcohol spectrum disorders
- neurodegeneration
- oxidative stress
- protein degradation
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Affiliation(s)
- Jia Luo
- a Department of Pharmacology and Nutritional Sciences ; University of Kentucky College of Medicine ; Lexington , KY USA
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31
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Hiura M, Honma Y, Miyagawa K, Oe S, Shimajiri S, Mihara H, Oe M, Sato-Morita M, Katsuki Y, Harada M. Alleviation mechanisms against hepatocyte oxidative stress in patients with chronic hepatic disorders. Hepatol Res 2015; 45:1124-35. [PMID: 25581125 DOI: 10.1111/hepr.12478] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/01/2014] [Revised: 01/05/2015] [Accepted: 01/06/2015] [Indexed: 02/08/2023]
Abstract
AIM Autophagy induction and Mallory-Denk body (MDB) formation have been considered to have cytoprotective effects from cellular stress in liver diseases. We investigated the relations among oxidative stress, autophagy and MDB formation in patients with chronic hepatitis B (CHB), chronic hepatitis C (CHC) and non-alcoholic fatty liver disease (NAFLD) to clarify the alleviation mechanisms against oxidative stress of hepatocytes. METHODS First, we treated cultured cells with proteasome inhibitor (PI) or free fatty acid (FFA) and evaluated endoplasmic reticulum (ER) stress, oxidative stress, ubiquitinated proteins and p62 by western blotting. Then, we used human liver biopsy samples to evaluate oxidative stress, autophagy and MDB formation by immunohistochemical analysis. RESULTS Treatment with PI or FFA increased ER stress, oxidative stress, ubiquitinated proteins and p62 in cultured cells. Human liver biopsy samples of CHC and NAFLD showed that MDB formed in areas with strong oxidative stress and that the MDB-containing cells circumvented oxidative stress. Keratin 8 (K8) expression was strong in MDB-containing cells in CHC and NAFLD. However, in CHB samples, the expression of K8 was not increased in response to oxidative stress and MDB aggregates did not appear. Aminotransferase values were significantly lower in patients with CHC and NAFLD in whom light chain 3 antibody expression was increased in response to oxidative stress. CONCLUSION Strong expression of K8 was considered to be important for MDB formation. MDB protect liver cells from oxidative stress at a cellular level and autophagy reduced hepatic damage when it was induced in the hepatocytes exposed to strong oxidative stress.
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Affiliation(s)
- Masaaki Hiura
- Third Department of Internal Medicine, Kitakyushu, Japan
| | - Yuichi Honma
- Third Department of Internal Medicine, Kitakyushu, Japan
| | | | - Shinji Oe
- Third Department of Internal Medicine, Kitakyushu, Japan
| | - Shohei Shimajiri
- Department of Pathology and Cell Biology, University of Occupational and Environmental Health, School of Medicine, Kitakyushu, Japan
| | - Hitomi Mihara
- Third Department of Internal Medicine, Kitakyushu, Japan
| | - Masami Oe
- Third Department of Internal Medicine, Kitakyushu, Japan
| | | | - Yuka Katsuki
- Third Department of Internal Medicine, Kitakyushu, Japan
| | - Masaru Harada
- Third Department of Internal Medicine, Kitakyushu, Japan
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32
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Kurahashi T, Hamashima S, Shirato T, Lee J, Homma T, Kang ES, Fujii J. An SOD1 deficiency enhances lipid droplet accumulation in the fasted mouse liver by aborting lipophagy. Biochem Biophys Res Commun 2015; 467:866-71. [PMID: 26474701 DOI: 10.1016/j.bbrc.2015.10.052] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2015] [Accepted: 10/09/2015] [Indexed: 12/12/2022]
Abstract
Under normal feeding conditions, oxidative stress stimulates lipid droplets accumulation in hepatocytes. We found that, despite the low visceral fat in Sod1-knockout (KO) mouse, lipid droplets accumulate in the liver to a greater extent than for the wild-type mouse upon fasting. Liver damage became evident in the KO mice. While fasting caused substantial endoplasmic reticulum stress in KO mice, the expression of genes involved in fatty acid production was suppressed. LC3-II, which is essential for the dynamic process of autophagosome formation, was activated in the wild-type mouse and enhanced in the KO mouse. However, the p62, an adapter protein with the ubiquitin- and LC3-binding activity, accumulated abnormally in the livers of KO mice, implying an abortive lipophagic process as the cause for the impaired lipid metabolism and the hepatic damage that occurs upon fasting.
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Affiliation(s)
- Toshihiro Kurahashi
- Department of Biochemistry and Molecular Biology, Graduate School of Medical Science, Yamagata University, Japan
| | - Shinji Hamashima
- Department of Biochemistry and Molecular Biology, Graduate School of Medical Science, Yamagata University, Japan
| | - Takaya Shirato
- Department of Biochemistry and Molecular Biology, Graduate School of Medical Science, Yamagata University, Japan
| | - Jaeyong Lee
- Department of Biochemistry and Molecular Biology, Graduate School of Medical Science, Yamagata University, Japan
| | - Takujiro Homma
- Department of Biochemistry and Molecular Biology, Graduate School of Medical Science, Yamagata University, Japan
| | - Eun Sil Kang
- Department of Biochemistry and Molecular Biology, Graduate School of Medical Science, Yamagata University, Japan
| | - Junichi Fujii
- Department of Biochemistry and Molecular Biology, Graduate School of Medical Science, Yamagata University, Japan.
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Circulating cell death biomarker: good candidates of prognostic indicator for patients with hepatitis B virus related acute-on-chronic liver failure. Sci Rep 2015; 5:14240. [PMID: 26383863 PMCID: PMC4585557 DOI: 10.1038/srep14240] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2015] [Accepted: 08/20/2015] [Indexed: 12/19/2022] Open
Abstract
Investigations on survival of patients with hepatitis B virus related acute-on-chronic liver failure (HBV-ACLF) are sparse and urgently needed. The current study aimed to evaluate the prognostic value of circulating cell death biomarkers (M30-anigen, M65-antigen and HMGB1) for HBV ACLF. In this prospective study (2/2013–8/2014), 94 patients including 54 HBV-ACLF and 40 chronic hepatitis B (CHB) patients were recruited. 40 healthy controls (HC) were also recruited. HBV-ACLF were followed up for 3 months for short-term mortality. All three biomarkers were significantly elevated in HBV-ACLF compared with CHB or HC. M30- and M65-antigens could significantly discriminate between non-survivors and survivors in HBV-ACLF. However, HMGB1 showed no prognostic value. By Cox regression analysis, M30- and M65-antigens and MELD were identified as independent predictors for short-term mortality. A novel prognostic model, MELD-CD (MELD-cell death) was established based on the multivariate results. The adjusted Harrell’s C-index of MELD-CD was 0.86 (P < 0.001) and was significantly higher (P < 0.001 for all) than the currently used models, MELD (C-index, 0.71, P < 0.001), MELD-NA (0.67, P < 0.001), CTPs (0.61, P < 0.05). Dynamic analyses further confirmed the prognostic utility of M30- and M65-antigen. Future studies are warranted to validate the results.
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DeLoach A, Cozart M, Kiaei A, Kiaei M. A retrospective review of the progress in amyotrophic lateral sclerosis drug discovery over the last decade and a look at the latest strategies. Expert Opin Drug Discov 2015; 10:1099-118. [PMID: 26307158 DOI: 10.1517/17460441.2015.1067197] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
INTRODUCTION Drug discovery for amyotrophic lateral sclerosis (ALS) has experienced a surge in clinical studies and remarkable preclinical milestones utilizing a variety of mutant superoxide dismutase 1 model systems. Of the drugs that were tested and showed positive preclinical effects, none demonstrated therapeutic benefits to ALS patients in clinical settings. AREAS COVERED This review discusses the advances made in drug discovery for ALS and highlights why drug development is proving to be so difficult. It also discusses how a closer look at both preclinical and clinical studies could uncover the reasons why these preclinical successes have yet to result in the availability of an effective drug for clinical use. EXPERT OPINION Valuable lessons from the numerous preclinical and clinical studies supply the biggest advantage in the monumental task of finding a cure for ALS. Obviously, a single design type for ALS clinical trials has not yielded success. The authors suggest a two-pronged approach that may prove essential to achieve clinical efficacy in the identification of novel targets and preclinical testing in multiple models to identify biomarkers that can function in diagnostic, predictive and prognostic roles, and changes to clinical trial design and patient recruitment criteria. The advancement of technology and invention of more powerful tools will further enhance the above. This will give rise to more sophisticated clinical trials with consideration of a range of criteria from: optimum dose, route of delivery, specific biomarkers, pharmacokinetics, pharmacodynamics and toxicology to biomarkers, timing for trial and patients' clinical status.
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Affiliation(s)
- Abigail DeLoach
- a 1 University of Arkansas for Medical Sciences, Department of Neurobiology and Developmental Sciences , Little Rock, AR 72205, USA
| | - Michael Cozart
- b 2 University of Arkansas for Medical Sciences, Department of Pharmacology and Toxicology , Little Rock, AR 72205, USA
| | - Arianna Kiaei
- a 1 University of Arkansas for Medical Sciences, Department of Neurobiology and Developmental Sciences , Little Rock, AR 72205, USA
| | - Mahmoud Kiaei
- a 1 University of Arkansas for Medical Sciences, Department of Neurobiology and Developmental Sciences , Little Rock, AR 72205, USA.,b 2 University of Arkansas for Medical Sciences, Department of Pharmacology and Toxicology , Little Rock, AR 72205, USA.,c 3 University of Arkansas for Medical Sciences, Department of Neurology , 4301 W. Markham St, 846, Little Rock, AR 72205 7199, USA
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Xie F, Jia L, Lin M, Shi Y, Yin J, Liu Y, Chen D, Meng Q. ASPP2 attenuates triglycerides to protect against hepatocyte injury by reducing autophagy in a cell and mouse model of non-alcoholic fatty liver disease. J Cell Mol Med 2014; 19:155-64. [PMID: 25256142 PMCID: PMC4288359 DOI: 10.1111/jcmm.12364] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2014] [Accepted: 06/10/2014] [Indexed: 01/01/2023] Open
Abstract
ASPP2 is a pro-apoptotic member of the p53 binding protein family. ASPP2 has been shown to inhibit autophagy, which maintains energy balance in nutritional deprivation. We attempted to identify the role of ASPP2 in the pathogenesis of non-alcoholic fatty liver disease (NAFLD). In a NAFLD cell model, control treated and untreated HepG2 cells were pre-incubated with GFP-adenovirus (GFP-ad) for 12 hrs and then treated with oleic acid (OA) for 24 hrs. In the experimental groups, the HepG2 cells were pre-treated with ASPP2-adenovirus (ASPP2-ad) or ASPP2-siRNA for 12 hrs and then treated with OA for 24 hrs. BALB/c mice fed a methionine- and choline-deficient (MCD) diet were used to generate a mouse model of NAFLD. The mice with fatty livers in the control group were pre-treated with injections of GFP-ad for 10 days. In the experimental group, the mice that had been pre-treated with ASPP2-ad were fed an MCD diet for 10 days. ASPP2-ad or GFP-ad was administered once every 5 days. Liver tissue from fatty liver patients and healthy controls were used to analyse the role of ASPP2. Autophagy, apoptosis markers and lipid metabolism mediators, were assessed with confocal fluorescence microscopy, immunohistochemistry, western blot and biochemical assays. ASPP2 overexpression decreased the triglyceride content and inhibited autophagy and apoptosis in the HepG2 cells. ASPP2-ad administration suppressed the MCD diet-induced autophagy, steatosis and apoptosis and decreased the previously elevated alanine aminotransferase levels. In conclusion, ASPP2 may participate in the lipid metabolism of non-alcoholic steatohepatitis and attenuate liver failure.
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Affiliation(s)
- Fang Xie
- Beijing You An Hospital, Affiliated Hospital of Capital Medical University, Beijing, China; Beijing Institute of Hepatology, Beijing, China
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Fu MY, He YJ, Lv X, Liu ZH, Shen Y, Ye GR, Deng YM, Shu JC. Transforming growth factor‑β1 reduces apoptosis via autophagy activation in hepatic stellate cells. Mol Med Rep 2014; 10:1282-8. [PMID: 25059289 PMCID: PMC4121427 DOI: 10.3892/mmr.2014.2383] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2013] [Accepted: 06/02/2014] [Indexed: 02/07/2023] Open
Abstract
Autophagy is a metabolic process that is important in fibrogenesis, in which cellular components are degraded by lysosomal machinery. Transforming growth factor β1 (TGF‑β1) is a potent fibrogenic cytokine involved in liver fibrosis; however, it remains elusive whether autophagy is regulated by TGF‑β1 in this process. In the present study, the function of TGF‑β1‑mediated autophagy in the proliferation and apoptosis of hepatic stellate cells (HSCs) was investigated. A rat HSC cell line (HSC‑T6) was incubated with or without TGF‑β1 followed by bafilomycin A1, and microtubule-associated proteins 1A/1B light chain 3 (LC3) small interfering (si)RNA was used to inhibit autophagy in order to assess the association between TGF‑β1 and autophagy. HSC‑T6 cell transient transfection was accomplished with a pLVX‑AcGFP‑N1‑rLC3B‑encoding plasmid. An MTS assay and flow cytometry were utilized to detect proliferation and apoptosis of HSC‑T6 cells. Quantitative polymerase chain reaction, immunofluorescence and western blot analysis were used to detect the presence of activation markers. Proliferation was increased and apoptosis was reduced in HSC‑T6 cells treated with TGF‑β1 compared with cells subjected to serum deprivation. However, when HSC‑T6 cells were treated with bafilomycin A1 and LC3 siRNA, increased apoptosis and reduced proliferation were observed. In addition, protein and mRNA expression levels of the autophagy marker LC3 were significantly increased. GFP‑LC3 punctate markings were more prolific following TGF‑β1 treatment of HSC‑T6 cells, indicating that TGF‑β1 may rescue HSC‑T6 cells from serum deprivation and reduce apoptosis via autophagy induction. The present study elucidated the possible functions of TGF‑β1‑mediated autophagy in the pathological process of liver fibrosis.
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Affiliation(s)
- Mei-Ya Fu
- Department of Gastroenterology, The Fourth Affiliated Hospital of the Medical College of Jinan University, Guangzhou Red Cross Hospital, Guangzhou, Guangdong 510220, P.R. China
| | - Ya-Jun He
- Department of Gastroenterology, The Fourth Affiliated Hospital of the Medical College of Jinan University, Guangzhou Red Cross Hospital, Guangzhou, Guangdong 510220, P.R. China
| | - Xia Lv
- Department of Gastroenterology, The Fourth Affiliated Hospital of the Medical College of Jinan University, Guangzhou Red Cross Hospital, Guangzhou, Guangdong 510220, P.R. China
| | - Zhi-He Liu
- Department of Gastroenterology, The Fourth Affiliated Hospital of the Medical College of Jinan University, Guangzhou Red Cross Hospital, Guangzhou, Guangdong 510220, P.R. China
| | - Yan Shen
- Department of Gastroenterology, The Fourth Affiliated Hospital of the Medical College of Jinan University, Guangzhou Red Cross Hospital, Guangzhou, Guangdong 510220, P.R. China
| | - Guo-Rong Ye
- Department of Gastroenterology, The Fourth Affiliated Hospital of the Medical College of Jinan University, Guangzhou Red Cross Hospital, Guangzhou, Guangdong 510220, P.R. China
| | - Yan-Mei Deng
- Department of Gastroenterology, The Fourth Affiliated Hospital of the Medical College of Jinan University, Guangzhou Red Cross Hospital, Guangzhou, Guangdong 510220, P.R. China
| | - Jian-Chang Shu
- Department of Gastroenterology, The Fourth Affiliated Hospital of the Medical College of Jinan University, Guangzhou Red Cross Hospital, Guangzhou, Guangdong 510220, P.R. China
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Genetic and chemical correction of cholesterol accumulation and impaired autophagy in hepatic and neural cells derived from Niemann-Pick Type C patient-specific iPS cells. Stem Cell Reports 2014; 2:866-80. [PMID: 24936472 PMCID: PMC4050353 DOI: 10.1016/j.stemcr.2014.03.014] [Citation(s) in RCA: 161] [Impact Index Per Article: 16.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2014] [Revised: 03/25/2014] [Accepted: 03/31/2014] [Indexed: 12/17/2022] Open
Abstract
Niemann-Pick type C (NPC) disease is a fatal inherited lipid storage disorder causing severe neurodegeneration and liver dysfunction with only limited treatment options for patients. Loss of NPC1 function causes defects in cholesterol metabolism and has recently been implicated in deregulation of autophagy. Here, we report the generation of isogenic pairs of NPC patient-specific induced pluripotent stem cells (iPSCs) using transcription activator-like effector nucleases (TALENs). We observed decreased cell viability, cholesterol accumulation, and dysfunctional autophagic flux in NPC1-deficient human hepatic and neural cells. Genetic correction of a disease-causing mutation rescued these defects and directly linked NPC1 protein function to impaired cholesterol metabolism and autophagy. Screening for autophagy-inducing compounds in disease-affected human cells showed cell type specificity. Carbamazepine was found to be cytoprotective and effective in restoring the autophagy defects in both NPC1-deficient hepatic and neuronal cells and therefore may be a promising treatment option with overall benefit for NPC disease. Generation of Niemann-Pick type C (NPC) disease patient-specific iPSCs NPC1 hepatic and neuronal cells show defects in cholesterol and autophagic flux TALEN-mediated genetic correction rescues the cholesterol and autophagy defects Autophagy inducers can restore functional autophagy and increase cell viability
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Eguchi A, Wree A, Feldstein AE. Biomarkers of liver cell death. J Hepatol 2014; 60:1063-74. [PMID: 24412608 DOI: 10.1016/j.jhep.2013.12.026] [Citation(s) in RCA: 148] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/27/2013] [Revised: 12/08/2013] [Accepted: 12/26/2013] [Indexed: 12/14/2022]
Abstract
Hepatocyte cell death during liver injury was classically viewed to occur by either programmed (apoptosis), or accidental, uncontrolled cell death (necrosis). Growing evidence from our increasing understanding of the biochemical and molecular mechanisms involved in cell demise has provided an expanding view of various modes of cell death that can be triggered during both acute and chronic liver damage such as necroptosis, pyroptosis, and autophagic cell death. The complexity of non-invasively assessing the predominant mode of cell death during a specific liver insult in either experimental in vivo models or in humans is highlighted by the fact that in many instances there is significant crosstalk and overlap between the different cell death pathways. Nevertheless, the realization that during cell demise triggered by a specific mode of cell death certain intracellular molecules such as proteins, newly generated protein fragments, or MicroRNAs are released from hepatocytes into the extracellular space and may appear in circulation have spurred a significant interest in the development of non-invasive markers to monitor liver cell death. This review focuses on some of the most promising markers, and their potential role in assessing the presence and severity of liver damage in humans.
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Affiliation(s)
- Akiko Eguchi
- Department of Pediatric Gastroenterology, Rady Children's Hospital, University of California San Diego, San Diego, CA 92123, United States
| | - Alexander Wree
- Department of Pediatric Gastroenterology, Rady Children's Hospital, University of California San Diego, San Diego, CA 92123, United States
| | - Ariel E Feldstein
- Department of Pediatric Gastroenterology, Rady Children's Hospital, University of California San Diego, San Diego, CA 92123, United States.
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Puri P, Chandra A. Autophagy modulation as a potential therapeutic target for liver diseases. J Clin Exp Hepatol 2014; 4:51-9. [PMID: 25755534 PMCID: PMC4017203 DOI: 10.1016/j.jceh.2014.04.001] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/10/2014] [Accepted: 04/01/2014] [Indexed: 12/12/2022] Open
Abstract
Autophagy is a critical intracellular pathway which maintains cellular function by lysosomal degradation of damaged proteins and organelles besides elimination of invading pathogens. Its primary function is to prevent cell death. Autophagy has diverse physiological functions namely; starvation adaptation, prevention of tumorigenesis, energy homeostasis, intracellular quality control and degradation of abnormal intracellular protein aggregates. Understanding the molecular mechanisms of autophagy has given key insights into the pathogenesis of various diseases like Non Alcoholic Steato-Hepatitis, Hepatitis B and C infections, Alpha-1 antitrypsin deficiency and hepatocellular carcinoma. Pharmacological modulation of autophagy may have a therapeutic potential in management of these liver diseases.
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Key Words
- AMPk, adenosine monophosphate-activated protein linase
- AT, antitrypsin
- ER, endoplasmic reticulum
- HBV, hepatitis B virus
- HCC, hepatocellular carcinoma
- HCV, hepatitis C virus
- HSC, hepatic stellate cells
- NASH, Non Alcoholic Steato-Hepatitis
- STEBPs, sterol regulatory element-binding proteins
- TG, triglyceride
- ULK1, Uncoordinated 51-like kinase 1
- autophagosome
- autophagy
- liver diseases
- mTORC1, mTOR complex 1
- mTORC2, mTOR complex 2
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Affiliation(s)
- Pankaj Puri
- Department of Gastroenterology, Army Hospital (Research and Referral), Dhaula Kuan, New Delhi 110010, India,Address for correspondence: Pankaj Puri, Department of Gastroenterology, Army Hospital (Research and Referral), Dhaula Kuan, New Delhi 110010, India.
| | - Alok Chandra
- Department of Gastroenterology, Command Hospital (EC), Alipore Road, Kolkata 700027, West Bengal, India
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Chen C, Deng M, Sun Q, Loughran P, Billiar TR, Scott MJ. Lipopolysaccharide stimulates p62-dependent autophagy-like aggregate clearance in hepatocytes. BIOMED RESEARCH INTERNATIONAL 2014; 2014:267350. [PMID: 24683544 PMCID: PMC3934718 DOI: 10.1155/2014/267350] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/07/2013] [Revised: 11/18/2013] [Accepted: 11/26/2013] [Indexed: 01/11/2023]
Abstract
Impairment of autophagy has been associated with liver injury. TLR4-stimulation by LPS upregulates autophagy in hepatocytes, although the signaling pathways involved remain elusive. The objective of this study was to determine the signaling pathway leading to LPS-stimulated autophagy in hepatocytes. Cell lysates from livers of wild type (WT; C57BL/6) mice given LPS (5 mg/kg-IP) and hepatocytes from WT, TLR4ko, and MyD88ko mice treated with LPS (100 ng/mL) up to 24 h were collected. LC3II, p62/SQSTM1, Nrf2, and beclin1 levels were determined by immunoblot, immunofluorescence, and qPCR. Autophagy-like activation was measured by GFP-LC3-puncta formation and LC3II-expression. Beclin1, Nrf2, p62, MyD88, and TIRAP were knocked-down using siRNA. LC3II-expression increased in both liver and hepatocytes after LPS and was dependent on TLR4. Beclin1 expression did not increase after LPS in hepatocytes and beclin1-knockdown did not affect LC3II levels. In hepatocytes given LPS, expression of p62 increased and p62 colocalized with LC3. p62-knockdown prevented LC3II puncta formation. LPS-induced LC3II/p62-puncta also required MyD88/TIRAP signaling and localization of both Nrf2 and NF κ B transcription factors to the nucleus to upregulate p62-expression. Therefore, TLR4-activation by LPS in hepatocytes induces a p62-mediated, not beclin1-mediated, autophagy-like clearance pathway that is hepatoprotective by clearing aggregate-prone or misfolded proteins from the cytosol and preserving energy homeostasis under stress.
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Affiliation(s)
- Christine Chen
- Department of Surgery, University of Pittsburgh, NW607 MUH, 3459 Fifth Avenue, Pittsburgh, PA 15213, USA
| | - Meihong Deng
- Department of Surgery, University of Pittsburgh, NW607 MUH, 3459 Fifth Avenue, Pittsburgh, PA 15213, USA
| | - Qian Sun
- Department of Surgery, University of Pittsburgh, NW607 MUH, 3459 Fifth Avenue, Pittsburgh, PA 15213, USA
- Department of Pathology, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Patricia Loughran
- Department of Surgery, University of Pittsburgh, NW607 MUH, 3459 Fifth Avenue, Pittsburgh, PA 15213, USA
- Center for Biologic Imaging, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Timothy R. Billiar
- Department of Surgery, University of Pittsburgh, NW607 MUH, 3459 Fifth Avenue, Pittsburgh, PA 15213, USA
| | - Melanie J. Scott
- Department of Surgery, University of Pittsburgh, NW607 MUH, 3459 Fifth Avenue, Pittsburgh, PA 15213, USA
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Notch-Nrf2 axis: regulation of Nrf2 gene expression and cytoprotection by notch signaling. Mol Cell Biol 2013; 34:653-63. [PMID: 24298019 DOI: 10.1128/mcb.01408-13] [Citation(s) in RCA: 101] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
The Notch signaling pathway enables regulation and control of development, differentiation, and homeostasis through cell-cell communication. Our investigation shows that Notch signaling directly activates the Nrf2 stress adaptive response pathway through recruitment of the Notch intracellular domain (NICD) transcriptosome to a conserved Rbpjκ site in the promoter of Nrf2. Stimulation of Notch signaling through Notch ligand expression in cells and by overexpression of the NICD in Rosa(NICD/-)::AlbCre mice in vivo induces expression of Nrf2 and its target genes. Continuous and transient NICD expression in the liver produces a Notch-dependent cytoprotective response through direct transcriptional activation of Nrf2 signaling to rescue mice from acute acetaminophen toxicity. This response can be reversed upon genetic disruption of Nrf2. Morphological studies showed that the characteristic phenotype of high-density intrahepatic bile ducts and enlarged liver in Rosa(NICD/-)::AlbCre mice could be at least partially reversed after Nrf2 disruption. Furthermore, the liver and bile duct phenotypes could be recapitulated with constitutive activation of Nrf2 signaling in Keap1(F/F)::AlbCre mice. It appears that Notch-to-Nrf2 signaling is another important determinant in liver development and function and promotes cell-cell cytoprotective signaling responses.
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Long-term fructose feeding changes the expression of leptin receptors and autophagy genes in the adipose tissue and liver of male rats: a possible link to elevated triglycerides. GENES AND NUTRITION 2013; 8:623-35. [PMID: 24085619 DOI: 10.1007/s12263-013-0357-3] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/29/2013] [Accepted: 09/23/2013] [Indexed: 01/21/2023]
Abstract
Long-term fructose consumption has been shown to evoke leptin resistance, to elevate triglyceride levels and to induce insulin resistance and hepatic steatosis. Autophagy has been suggested to function in processes such as lipid storage in adipose tissue and inflammation in liver. Autophagy and the leptin system have also been suggested to regulate each other. This study aimed to identify the changes caused by fetal undernourishment and postnatal fructose diet in the gene expression of leptin, its receptors (LEPR-a, LEPR-b, LEPR-c, LEPR-e and LEPR-f) and autophagy genes in the white adipose tissue (WAT) and liver of adult male rats in order to clarify the mechanism behind the metabolic alterations. The data clearly revealed that the long-term postnatal fructose diet decreased leptin levels (p < 0.001), LEPR (p < 0.001), especially LEPR-b (p = 0.011) and LEPR-f (p = 0.005), as well as SOCS3 (p < 0.001), ACC (p = 0.006), ATG7 (p < 0.001), MAP1LC3β (p < 0.001) and LAMP2 (p = 0.004) mRNA expression in WAT. Furthermore, LEPR (p < 0.001), especially LEPR-b (p = 0.001) and LEPR-f (p < 0.001), ACC (p = 0.010), ATG7 (p = 0.024), MAP1LC3β (p = 0.003) and LAMP2 (p < 0.001) mRNA expression in the liver was increased in fructose-fed rats. In addition, the LEPR expression in liver and MAP1LC3β expression in WAT together explained 55.7 % of the variation in the plasma triglyceride levels of the rats (R adj. (2) = 0.557, p < 0.001). These results, together with increased p62 levels in WAT (p < 0.001), could indicate decreased adipose tissue lipid storing capacity as well as alterations in liver metabolism which may represent a plausible mechanism through which fructose consumption could disturb lipid metabolism and result in elevated triglyceride levels.
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Glycogen storage disease type 1 and diabetes: Learning by comparing and contrasting the two disorders. DIABETES & METABOLISM 2013; 39:377-87. [DOI: 10.1016/j.diabet.2013.03.002] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2013] [Revised: 02/25/2013] [Accepted: 03/11/2013] [Indexed: 12/18/2022]
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Kaden TR, Li W. AUTOPHAGY, MITOCHONDRIAL DYNAMICS AND RETINAL DISEASES. Asia Pac J Ophthalmol (Phila) 2013; 2:S2162-0989(23)01010-1. [PMID: 24205447 PMCID: PMC3816775 DOI: 10.1097/apo.0b013e31829d3e33] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Affiliation(s)
- Talia R. Kaden
- National Eye Institute, National Institutes of Health, Bethesda, MD, USA
- Yale University School of Medicine, New Haven, CT, USA
| | - Wei Li
- National Eye Institute, National Institutes of Health, Bethesda, MD, USA
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Li S, Du L, Zhang L, Hu Y, Xia W, Wu J, Zhu J, Chen L, Zhu F, Li C, Yang S. Cathepsin B contributes to autophagy-related 7 (Atg7)-induced nod-like receptor 3 (NLRP3)-dependent proinflammatory response and aggravates lipotoxicity in rat insulinoma cell line. J Biol Chem 2013; 288:30094-30104. [PMID: 23986436 DOI: 10.1074/jbc.m113.494286] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Impairment of glucose-stimulated insulin secretion caused by the lipotoxicity of palmitate was found in β-cells. Recent studies have indicated that defects in autophagy contribute to pathogenesis in type 2 diabetes. Here, we report that autophagy-related 7 (Atg7) induced excessive autophagic activation in INS-1(823/13) cells exposed to saturated fatty acids. Atg7-induced cathepsin B (CTSB) overexpression resulted in an unexpected significant increase in proinflammatory chemokine and cytokine production levels of IL-1β, monocyte chemotactic protein-1, IL-6, and TNF-α. Inhibition of receptor-interacting protein did not affect the inflammatory response, ruling out involvement of necrosis. CTSB siRNA suppressed the inflammatory response but did not affect apoptosis significantly, suggesting that CTSB was a molecular linker between autophagy and the proinflammatory response. Blocking caspase-3 suppressed apoptosis but did not affect the inflammatory response, suggesting that CTSB induced inflammatory effects independently of apoptosis. Silencing of Nod-like receptor 3 (NLRP3) completely abolished both IL-1β secretion and the down-regulation effects of Atg7-induced CTSB overexpression on glucose-stimulated insulin secretion impairment, thus identifying the NLRP3 inflammasome as an autophagy-responsive element in the pancreatic INS-1(823/13) cell line. Combined together, our results indicate that CTSB contributed to the Atg7-induced NLRP3-dependent proinflammatory response, resulting in aggravation of lipotoxicity, independently of apoptosis in the pancreatic INS-1(823/13) cell line.
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Affiliation(s)
- Shali Li
- From the Department of Cell Biology, College of Life Science, Nanjing Normal University, Nanjing, Jiangsu Province 210046, China
| | - Leilei Du
- From the Department of Cell Biology, College of Life Science, Nanjing Normal University, Nanjing, Jiangsu Province 210046, China
| | - Lu Zhang
- From the Department of Cell Biology, College of Life Science, Nanjing Normal University, Nanjing, Jiangsu Province 210046, China
| | - Yue Hu
- From the Department of Cell Biology, College of Life Science, Nanjing Normal University, Nanjing, Jiangsu Province 210046, China
| | - Wenchun Xia
- From the Department of Cell Biology, College of Life Science, Nanjing Normal University, Nanjing, Jiangsu Province 210046, China
| | - Jia Wu
- From the Department of Cell Biology, College of Life Science, Nanjing Normal University, Nanjing, Jiangsu Province 210046, China
| | - Jing Zhu
- From the Department of Cell Biology, College of Life Science, Nanjing Normal University, Nanjing, Jiangsu Province 210046, China
| | - Lingling Chen
- From the Department of Cell Biology, College of Life Science, Nanjing Normal University, Nanjing, Jiangsu Province 210046, China
| | - Fengqi Zhu
- From the Department of Cell Biology, College of Life Science, Nanjing Normal University, Nanjing, Jiangsu Province 210046, China
| | - Chunxian Li
- From the Department of Cell Biology, College of Life Science, Nanjing Normal University, Nanjing, Jiangsu Province 210046, China
| | - SiJun Yang
- From the Department of Cell Biology, College of Life Science, Nanjing Normal University, Nanjing, Jiangsu Province 210046, China.
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Codogno P, Meijer AJ. Autophagy in the liver. J Hepatol 2013; 59:389-91. [PMID: 23669287 DOI: 10.1016/j.jhep.2013.02.031] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/15/2013] [Revised: 02/18/2013] [Accepted: 02/19/2013] [Indexed: 02/06/2023]
Affiliation(s)
- Patrice Codogno
- INSERM U845, Necker Medical School, University Paris-Descartes, 75015 Paris, France.
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Garlic-Derived S-Allylmercaptocysteine Ameliorates Nonalcoholic Fatty Liver Disease in a Rat Model through Inhibition of Apoptosis and Enhancing Autophagy. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2013; 2013:642920. [PMID: 23861709 PMCID: PMC3703729 DOI: 10.1155/2013/642920] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/18/2012] [Revised: 03/11/2013] [Accepted: 03/12/2013] [Indexed: 12/19/2022]
Abstract
Our previous study demonstrated that administration of garlic-derived antioxidant S-allylmercaptocysteine (SAMC) ameliorated hepatic injury in a nonalcoholic fatty liver disease (NAFLD) rat model. Our present study aimed to investigate the mechanism of SAMC on NAFLD-induced hepatic apoptosis and autophagy. Adult female rats were fed with a high-fat diet for 8 weeks to develop NAFLD with or without intraperitoneal injection of 200 mg/kg SAMC for three times per week. During NAFLD development, increased apoptotic cells and caspase-3 activation were observed in the liver. Increased apoptosis was modulated through both intrinsic and extrinsic apoptotic pathways. NAFLD treatment also enhanced the expression of key autophagic markers in the liver with reduced activity of LKB1/AMPK and PI3K/Akt pathways. Increased expression of proapoptotic regulator p53 and decreased activity of antiautophagic regulator mTOR were also observed. Administration of SAMC reduced the number of apoptotic cells through downregulation of both intrinsic and extrinsic apoptotic mechanisms. SAMC also counteracted the effects of NAFLD on LKB1/AMPK and PI3K/Akt pathways. Treatment with SAMC further enhanced hepatic autophagy by regulating autophagic markers and mTOR activity. In conclusion, administration of SAMC during NAFLD development in rats protects the liver from chronic injury by reducing apoptosis and enhancing autophagy.
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Gebhardt R, Coffer PJ. Hepatic autophagy is differentially regulated in periportal and pericentral zones - a general mechanism relevant for other tissues? Cell Commun Signal 2013; 11:21. [PMID: 23531205 PMCID: PMC3623826 DOI: 10.1186/1478-811x-11-21] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2012] [Accepted: 03/11/2013] [Indexed: 02/08/2023] Open
Abstract
Background Liver zonation, the fact that metabolic pathways are spatially separated along the liver sinusoids, is fundamental for proper functioning of this organ. For example, glutamine synthesis from glutamate and ammonia is localized pericentrally in only 7% of the hepatocytes concentrically arranged around the central veins. Recently, we found that FOXO transcription factors lead to upregulation of glutamine synthetase expression inducing autophagy via increasing glutamine production. Since in liver this mechanism can only be functioning in the pericentral zone it remains unclear how autophagy might be regulated in the rest of liver parenchyma. Presentation of the hypothesis We hypothesize that the regulation of autophagy by glutamine in liver is zonated. In the periportal zone, autophagy is inhibited by low intracellular glutamine but high essential amino acids, while in the pericentral zone it is stimulated by high intracellular glutamine. This zonation may be controlled by the Wnt and Hedgehog signalling pathways through reciprocal influence on the expression of amino acid transporters and metabolic enzymes in the different zones of the parenchyma. Testing the hypothesis The hypothesis can be tested in transgenic mice with conditional hepatocyte-specific modulation of Wnt and Hedgehog signalling. Isolated periportal and pericentral hepatocyte populations allow for determining the different activities of autophagy and its regulating mechanisms in different zones of the parenchyma. Implications of the hypothesis Zonation of the regulation of autophagy may allow adapting the extent of the proteolytic breakdown of proteins and organelles to different physiological needs in different zones of liver parenchyma. In this manner metabolic functions can be supported in one zone, for example maintenance of blood glucose levels during starvation which is a periportal issue, while simultaneously preventing cytotoxic events in the opposite zone. Likewise, lipid metabolism can be differentially influenced by uncoupling periportal lipophagy from pericentral breakdown of peroxisomes. Further implications concern the shaping of morphogen gradients along the sinusoidal axis by autophagy, and the different contribution of autophagy to the development of various different liver pathologies. The proposed dependence of the dual glutamine-dependent regulatory mechanisms of autophagy on inverse gradients of Wnt and hedgehog signalling may be relevant for other tissues in which GS is heterogeneously expressed.
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Affiliation(s)
- Rolf Gebhardt
- Institute of Biochemistry, Faculty of Medicine, University of Leipzig, Leipzig, Germany.
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Cui J, Gong Z, Shen HM. The role of autophagy in liver cancer: molecular mechanisms and potential therapeutic targets. Biochim Biophys Acta Rev Cancer 2013; 1836:15-26. [PMID: 23428608 DOI: 10.1016/j.bbcan.2013.02.003] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2012] [Revised: 02/08/2013] [Accepted: 02/08/2013] [Indexed: 02/07/2023]
Abstract
Autophagy is an evolutionarily conserved pathway for degradation of cytoplasmic proteins and organelles via lysosome. Proteins coded by the autophagy-related genes (Atgs) are the core molecular machinery in control of autophagy. Among the various biological functions of autophagy identified so far, the link between autophagy and cancer is probably among the most extensively studied and is often viewed as controversial. Autophagy might exert a dual role in cancer development: autophagy can serve as an anti-tumor mechanism, as defective autophagy (e.g., heterozygous knockdown Beclin 1 and Atg7 in mice) promotes the malignant transformation and spontaneous tumors. On the other hand, autophagy functions as a protective or survival mechanism in cancer cells against cellular stress (e.g., nutrient deprivation, hypoxia and DNA damage) and hence promotes tumorigenesis and causes resistance to therapeutic agents. Liver cancer is one of the common cancers with well-established etiological factors including hepatitis virus infection and environmental carcinogens such as aflatoxin and alcohol exposure. In recent years, the involvement of autophagy in liver cancer has been increasingly studied. Here, we aim to provide a systematic review on the close cross-talks between autophagy and liver cancer, and summarize the current status in development of novel liver cancer therapeutic approaches by targeting autophagy. It is believed that understanding the molecular mechanisms underlying the autophagy modulation and liver cancer development may provoke the translational studies that ultimately lead to new therapeutic strategies for liver cancer.
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Affiliation(s)
- Jianzhou Cui
- Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
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