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Yan C, Hu W, Tu J, Li J, Liang Q, Han S. Pathogenic mechanisms and regulatory factors involved in alcoholic liver disease. J Transl Med 2023; 21:300. [PMID: 37143126 PMCID: PMC10158301 DOI: 10.1186/s12967-023-04166-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2023] [Accepted: 04/27/2023] [Indexed: 05/06/2023] Open
Abstract
Alcoholism is a widespread and damaging behaviour of people throughout the world. Long-term alcohol consumption has resulted in alcoholic liver disease (ALD) being the leading cause of chronic liver disease. Many metabolic enzymes, including alcohol dehydrogenases such as ADH, CYP2E1, and CATacetaldehyde dehydrogenases ALDHsand nonoxidative metabolizing enzymes such as SULT, UGT, and FAEES, are involved in the metabolism of ethanol, the main component in alcoholic beverages. Ethanol consumption changes the functional or expression profiles of various regulatory factors, such as kinases, transcription factors, and microRNAs. Therefore, the underlying mechanisms of ALD are complex, involving inflammation, mitochondrial damage, endoplasmic reticulum stress, nitrification, and oxidative stress. Moreover, recent evidence has demonstrated that the gut-liver axis plays a critical role in ALD pathogenesis. For example, ethanol damages the intestinal barrier, resulting in the release of endotoxins and alterations in intestinal flora content and bile acid metabolism. However, ALD therapies show low effectiveness. Therefore, this review summarizes ethanol metabolism pathways and highly influential pathogenic mechanisms and regulatory factors involved in ALD pathology with the aim of new therapeutic insights.
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Affiliation(s)
- Chuyun Yan
- Department of Hepatobiliary Surgery, Anhui Province Key Laboratory of Hepatopancreatobiliary Surgery, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, 230001, Anhui, China
| | - Wanting Hu
- MOE Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology, Key Lab of Microanalytical Methods & Instrumentation, Department of Chemistry, Center for Synthetic and Systems Biology, Tsinghua University, Beijing, 100084, China
| | - Jinqi Tu
- The First Affiliated Hospital of Wannan Medical College, Yijishan Hospital of Wannan Medical College of Wuhu, Wannan Medical College, Wuhu, 241000, Anhui, China
| | - Jinyao Li
- Xinjiang Key Laboratory of Biological Resources and Genetic Engineering, College of Life Science and Technology, Xinjiang University, Urumqi, 830046, China
| | - Qionglin Liang
- MOE Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology, Key Lab of Microanalytical Methods & Instrumentation, Department of Chemistry, Center for Synthetic and Systems Biology, Tsinghua University, Beijing, 100084, China
| | - Shuxin Han
- Department of Hepatobiliary Surgery, Anhui Province Key Laboratory of Hepatopancreatobiliary Surgery, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, 230001, Anhui, China.
- Xinjiang Key Laboratory of Biological Resources and Genetic Engineering, College of Life Science and Technology, Xinjiang University, Urumqi, 830046, China.
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Thomes PG, Rensch G, Casey CA, Donohue TM. Ethanol Exposure to Ethanol-Oxidizing HEPG2 Cells Induces Intracellular Protein Aggregation. Cells 2023; 12:cells12071013. [PMID: 37048086 PMCID: PMC10093015 DOI: 10.3390/cells12071013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2023] [Revised: 03/05/2023] [Accepted: 03/22/2023] [Indexed: 03/29/2023] Open
Abstract
Background: Aggresomes are collections of intracellular protein aggregates. In liver cells of patients with alcoholic hepatitis, aggresomes appear histologically as cellular inclusions known as Mallory–Denk (M–D) bodies. The proteasome is a multicatalytic intracellular protease that catalyzes the degradation of both normal (native) and abnormal (misfolded and/or damaged) proteins. The enzyme minimizes intracellular protein aggregate formation by rapidly degrading abnormal proteins before they form aggregates. When proteasome activity is blocked, either by specific inhibitors or by intracellular oxidants (e.g., peroxynitrite, acetaldehyde), aggresome formation is enhanced. Here, we sought to verify whether inhibition of proteasome activity by ethanol exposure enhances protein aggregate formation in VL-17A cells, which are recombinant, ethanol-oxidizing HepG2 cells that express both alcohol dehydrogenase (ADH) and cytochrome P450 2E1 (CYP2E1). Methods: We exposed ethanol-non-oxidizing HepG2 cells (ADH−/CYP2E1−) or ethanol-oxidizing VL-17A (ADH+/CYP2E1+) to varying levels of ethanol for 24 h or 72 h. After these treatments, we stained cells for aggresomes (detected microscopically) and quantified their numbers and sizes. We also conducted flow cytometric analyses to confirm our microscopic findings. Additionally, aggresome content in liver cells of patients with alcohol-induced hepatitis was quantified. Results: After we exposed VL-17A cells to increasing doses of ethanol for 24 h or 72 h, 20S proteasome activity declined in response to rising ethanol concentrations. After 24 h of ethanol exposure, aggresome numbers in VL-17A cells were 1.8-fold higher than their untreated controls at all ethanol concentrations employed. After 72 h of ethanol exposure, mean aggresome numbers were 2.5-fold higher than unexposed control cells. The mean aggregate size in all ethanol-exposed VL-17A cells was significantly higher than in unexposed control cells but was unaffected by the duration of ethanol exposure. Co-exposure of cells to EtOH and rapamycin, the latter an autophagy activator, completely prevented EtOH-induced aggresome formation. In the livers of patients with alcohol-induced hepatitis (AH), the staining intensity of aggresomes was 2.2-fold higher than in the livers of patients without alcohol use disorder (AUD). Conclusions: We conclude that ethanol-induced proteasome inhibition in ethanol-metabolizing VL-17A hepatoma cells causes accumulation of protein aggregates. Notably, autophagy activation removes such aggregates. The significance of these findings is discussed.
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Affiliation(s)
- Paul G. Thomes
- Liver Study Unit, VA-Nebraska-Western Iowa Health Care System, Omaha, NE 68105, USA
- The Depts of Internal Medicine, University of Nebraska Medical Center, Omaha, NE 68198, USA
- Biochemistry/Molecular Biology, University of Nebraska Medical Center, Omaha, NE 68198, USA
- Correspondence: ; Tel.: +1-402-995-3738; Fax: +1-402-449-0604
| | - Gage Rensch
- The Depts of Internal Medicine, University of Nebraska Medical Center, Omaha, NE 68198, USA
| | - Carol A. Casey
- Liver Study Unit, VA-Nebraska-Western Iowa Health Care System, Omaha, NE 68105, USA
- The Depts of Internal Medicine, University of Nebraska Medical Center, Omaha, NE 68198, USA
- Biochemistry/Molecular Biology, University of Nebraska Medical Center, Omaha, NE 68198, USA
| | - Terrence M. Donohue
- Liver Study Unit, VA-Nebraska-Western Iowa Health Care System, Omaha, NE 68105, USA
- The Depts of Internal Medicine, University of Nebraska Medical Center, Omaha, NE 68198, USA
- Biochemistry/Molecular Biology, University of Nebraska Medical Center, Omaha, NE 68198, USA
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Samuvel DJ, Li L, Krishnasamy Y, Gooz M, Takemoto K, Woster PM, Lemasters JJ, Zhong Z. Mitochondrial depolarization after acute ethanol treatment drives mitophagy in living mice. Autophagy 2022; 18:2671-2685. [PMID: 35293288 PMCID: PMC9629059 DOI: 10.1080/15548627.2022.2046457] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Revised: 02/18/2022] [Accepted: 02/22/2022] [Indexed: 12/15/2022] Open
Abstract
Ethanol increases hepatic mitophagy driven by unknown mechanisms. Type 1 mitophagy sequesters polarized mitochondria for nutrient recovery and cytoplasmic remodeling. In Type 2, mitochondrial depolarization (mtDepo) initiates mitophagy to remove the damaged organelles. Previously, we showed that acute ethanol administration produces reversible hepatic mtDepo. Here, we tested the hypothesis that ethanol-induced mtDepo initiates Type 2 mitophagy. GFP-LC3 transgenic mice were gavaged with ethanol (2-6 g/kg) with and without pre-treatment with agents that decrease or increase mtDepo-Alda-1, tacrolimus, or disulfiram. Without ethanol, virtually all hepatocytes contained polarized mitochondria with infrequent autophagic GFP-LC3 puncta visualized by intravital microscopy. At ~4 h after ethanol treatment, mtDepo occurred in an all-or-none fashion within individual hepatocytes, which increased dose dependently. GFP-LC3 puncta increased in parallel, predominantly in hepatocytes with mtDepo. Mitochondrial PINK1 and PRKN/parkin also increased. After covalent labeling of mitochondria with MitoTracker Red (MTR), GFP-LC3 puncta encircled MTR-labeled mitochondria after ethanol treatment, directly demonstrating mitophagy. GFP-LC3 puncta did not associate with fat droplets visualized with BODIPY558/568, indicating that increased autophagy was not due to lipophagy. Before ethanol administration, rhodamine-dextran (RhDex)-labeled lysosomes showed little association with GFP-LC3. After ethanol treatment, TFEB (transcription factor EB) translocated to nuclei, and lysosomal mass increased. Many GFP-LC3 puncta merged with RhDex-labeled lysosomes, showing autophagosomal processing into lysosomes. After ethanol treatment, disulfiram increased, whereas Alda-1 and tacrolimus decreased mtDepo, and mitophagy changed proportionately. In conclusion, mtDepo after acute ethanol treatment induces mitophagic sequestration and subsequent lysosomal processing.Abbreviations : AcAld, acetaldehyde; ADH, alcohol dehydrogenase; ALDH, aldehyde dehydrogenase; ALD, alcoholic liver disease; Alda-1, N-(1,3-benzodioxol-5-ylmethyl)-2,6-dichlorobenzamide; GAPDH, glyceraldehyde-3-phosphate dehydrogenase; GFP, green fluorescent protein; LAMP1, lysosomal-associated membrane protein 1; LMNB1, lamin B1; MAA, malondialdehyde-acetaldehyde adducts; MAP1LC3/LC3, microtubule-associated protein 1 light chain 3; MPT, mitochondrial permeability transition; mtDAMPS, mitochondrial damage-associated molecular patterns; mtDepo, mitochondrial depolarization; mtDNA, mitochondrial DNA; MTR, MitoTracker Red; PI, propidium iodide; PINK1, PTEN induced putative kinase 1; PRKN, parkin; RhDex, rhodamine dextran; TFEB, transcription factor EB; Tg, transgenic; TMRM, tetramethylrhodamine methylester; TOMM20, translocase of outer mitochondrial membrane 20; VDAC, voltage-dependent anion channel.
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Affiliation(s)
- Devadoss J. Samuvel
- Departments of Drug Discovery & Biomedical Science, Medical University of South Carolin, Charleston, SC, USA
| | - Li Li
- Departments of Drug Discovery & Biomedical Science, Medical University of South Carolin, Charleston, SC, USA
| | - Yasodha Krishnasamy
- Departments of Drug Discovery & Biomedical Science, Medical University of South Carolin, Charleston, SC, USA
| | - Monika Gooz
- Departments of Drug Discovery & Biomedical Science, Medical University of South Carolin, Charleston, SC, USA
| | - Kenji Takemoto
- Departments of Drug Discovery & Biomedical Science, Medical University of South Carolin, Charleston, SC, USA
| | - Patrick M. Woster
- Departments of Drug Discovery & Biomedical Science, Medical University of South Carolin, Charleston, SC, USA
| | - John J. Lemasters
- Departments of Drug Discovery & Biomedical Science, Medical University of South Carolin, Charleston, SC, USA
- Department of Biochemistry & Molecular Biology, Medical University of South Carolina, Charleston, SC, USA
| | - Zhi Zhong
- Departments of Drug Discovery & Biomedical Science, Medical University of South Carolin, Charleston, SC, USA
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Ameliorative Impacts of Wheat Germ Oil against Ethanol-Induced Hepatic and Renal Dysfunction in Rats: Involvement of Anti-Inflammatory, Anti-Apoptotic, and Antioxidant Signaling Pathways. LIFE (BASEL, SWITZERLAND) 2022; 12:life12101671. [PMID: 36295108 PMCID: PMC9605469 DOI: 10.3390/life12101671] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/08/2022] [Revised: 10/19/2022] [Accepted: 10/19/2022] [Indexed: 11/07/2022]
Abstract
Wheat germ oil (WGO) is a well-known product with anti-inflammatory and antioxidant properties. The current study aimed to investigate the impacts of WGO against ethanol-induced liver and kidney dysfunction at the serum, anti-inflammatory, antioxidants and anti-apoptotic signaling pathways. Rats received saline orally as a negative control or WGO in a dose of 1.5 mL/kg (1400 mg/kg body weight orally) for 15 days. The affected group received ethanol 50% v/v 10 mL/kg (5 g/kg) body weight orally once a day for consecutive 15 days to induce hepatorenal injuries in ethanolic non-treated group. The protective group received WGO daily 1 h before ethanol administration. Serum (1.5 mL) from blood was extracted and examined for the changes in biochemical assessments in serum alkaline phosphatase (ALP), alanine aminotransferase (ALT), bilirubin, serum γ-glutamyl transpeptidase (GGT), total protein, serum albumin, butyrylcholinesterase (BChE), total cholesterol (TC), total triglyceride (TG), urea, creatinine, uric acid, potassium (K+), Beta-2 microglobulin (β2M), malondialdehyde (MDA), catalase (CAT), reduced glutathione (GSH), superoxide dismutase (SOD) and aspartate aminotransferase (AST). Kidney and liver homogenate was used to measure MDA, GSH and catalase activities. Quantitative real time PCR (qRT-PCR) was used to express Nrf2 and HO-1 in liver, and NF-kB and kidney injury molecule (KIM-1) in kidneys, which are correlated with oxidative stress and inflammation. Capase-3 and Bcl2 genes were examined using immunohistochemical analysis in the kidney and liver. Ethanol administration induced significant alteration in examined liver and kidney markers (AST, ALT, GGT, ALP, total proteins, urea, creatinine and uric acid). Moreover, alcohol administration decreased antioxidant activities at serum and hepatorenal tissues (GSH, catalase and SOD), while MDA was increased as a tissue degradation marker. Inflammatory cytokines, together with genes of oxidative stress markers (Nrf2 and HO-1), were all affected. At cellular levels, apoptotic marker caspase-3 was upregulated, while antiapoptotic marker B-cell lymphoma 2 (Bcl2), was down regulated using immunohistochemical analysis. Of interest, pretreatment with WGO improved the side effects induced by ethanol on hepatic, renal biomarkers and reversed its impact on serum and tissue antioxidant parameters. Nrf2/HO-1 were upregulated, while NFk-B and KIM-1 were downregulated using real time PCR. Immune reactivities of caspase-3 and Bcl2 genes were restored in the protective group. In conclusion, WGO ameliorated ethanol-induced hepatic and renal dysfunction at the biochemical, molecular and cellular levels by regulating some mechanisms that controls oxidative stress, apoptosis, inflammation and anti-apoptotic pathways.
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Pal L, Agrawal S, Gautam A. Voacanga grandifolia (Miq.) Rolfe protects against alcohol-induced liver toxicity in rats. Asian Pac J Trop Biomed 2022. [DOI: 10.4103/2221-1691.363876] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
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Chen C, Wang S, Yu L, Mueller J, Fortunato F, Rausch V, Mueller S. H 2O 2-mediated autophagy during ethanol metabolism. Redox Biol 2021; 46:102081. [PMID: 34343907 PMCID: PMC8350071 DOI: 10.1016/j.redox.2021.102081] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2021] [Revised: 07/15/2021] [Accepted: 07/22/2021] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Alcoholic liver disease (ALD) is the most common liver disease worldwide and its underlying molecular mechanisms are still poorly understood. Moreover, conflicting data have been reported on potentially protective autophagy, the exact role of ethanol-metabolizing enzymes and ROS. METHODS Expression of LC3B, CYP2E1, and NOX4 was studied in a mouse model of acute ethanol exposure by immunoblotting and immunohistochemistry. Autophagy was further studied in primary mouse hepatocytes and huh7 cells in response to ethanol and its major intermediator acetaldehyde. Experiments were carried out in cells overexpressing CYP2E1 and knock down of NOX4 using siRNA. The response to external H2O2 was studied by using the GOX/CAT system. Autophagic flux was monitored using the mRFP-GFP-LC3 plasmid, while rapamycin and chloroquine served as positive and negative controls. RESULTS Acute ethanol exposure of mice over 24 h significantly induced autophagy as measured by LC3B expression but also induced the ROS-generating CYP2E1 and NOX4 enzymes. Notably, ethanol but not its downstream metabolite acetaldehyde induced autophagy in primary mouse hepatocytes. In contrast, autophagy could only be induced in huh7 cells in the presence of overexpressed CYP2E1. In addition, overexpression of NOX4 also significantly increased autophagy, which could be blocked by siRNA mediated knock down. The antioxidant N-acetylcysteine (NAC) also efficiently blocked CYP2E1-and NOX4-mediated induction of autophagy. Finally, specific and non-toxic production of H2O2 by the GOX/CAT system as evidenced by elevated peroxiredoxin (Prx-2) also induced LC3B which was efficiently blocked by NAC. H2O2 strongly increased the autophagic flux as measured by mRFP-GFP-LC3 plasmid. CONCLUSION We here provide evidence that short-term ethanol exposure induces autophagy in hepatocytes both in vivo and in vitro through the generation of ROS. These data suggest that suppression of autophagy by ethanol is most likely due to longer alcohol exposure during chronic alcohol consumption with the accumulation of e.g. misfolded proteins.
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Affiliation(s)
- Cheng Chen
- Center for Alcohol Research and Salem Medical Center, University of Heidelberg, Heidelberg, Germany
| | - Shijin Wang
- Center for Alcohol Research and Salem Medical Center, University of Heidelberg, Heidelberg, Germany
| | - Linna Yu
- Center for Alcohol Research and Salem Medical Center, University of Heidelberg, Heidelberg, Germany
| | - Johannes Mueller
- Center for Alcohol Research and Salem Medical Center, University of Heidelberg, Heidelberg, Germany
| | - Franco Fortunato
- Department of Surgery, University of Heidelberg, Heidelberg, Germany
| | - Vanessa Rausch
- Center for Alcohol Research and Salem Medical Center, University of Heidelberg, Heidelberg, Germany
| | - Sebastian Mueller
- Center for Alcohol Research and Salem Medical Center, University of Heidelberg, Heidelberg, Germany.
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Zhao Y, Lu J, Mao A, Zhang R, Guan S. Autophagy Inhibition Plays a Protective Role in Ferroptosis Induced by Alcohol via the p62-Keap1-Nrf2 Pathway. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2021; 69:9671-9683. [PMID: 34388345 DOI: 10.1021/acs.jafc.1c03751] [Citation(s) in RCA: 43] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Binge alcohol consumption is a serious health concern. Ferroptosis is an iron-dependent lipid peroxidation mediated cell death. Activation of the Kelch-like ECH-associated protein 1 (Keap1)-nuclear factor erythroid 2-related factor 2 (Nrf2) pathway has been shown to exert a protective effect by blunting the responses to ferroptosis inducers. The autophagy substrate p62 was demonstrated to modulate Nrf2 and contribute to the suppression of ferroptosis. Furthermore, autophagy inhibition resulted in the accumulation of p62, which is a specific substrate for this process. Therefore, we aimed to explore the protective effect of autophagy inhibition against alcohol-induced ferroptosis through activating the p62-Keap1-Nrf2 pathway. Our results demonstrated that alcohol induced ferroptosis, which could be significantly reduced by ferrostatin-1. Additionally, we found that autophagy inhibition could protect HepG2 cells against alcohol-induced ferroptosis by activating the p62-Keap1-Nrf2 pathway. Furthermore, inhibition of autophagy increased the expression of p62, which interacted with Keap1 to promote Nrf2 translocation into the nucleus and upregulation its target proteins ferritin heavy (FTH), ferroportin (FPN), and heme oxygenase-1 (HO-1). This study provides a theoretical basis for further elucidation of the relationship between autophagy and ferroptosis and lays a preliminary foundation for further research concerning dietary guidance in the prevention and treatment of diseases related to alcohol-induced ferroptosis.
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Affiliation(s)
- Yanan Zhao
- College of Food Science and Engineering, Jilin University, Changchun, Jilin 130062, People's Republic of China
| | - Jing Lu
- College of Food Science and Engineering, Jilin University, Changchun, Jilin 130062, People's Republic of China
- Key Laboratory of Zoonosis, Ministry of Education College of Veterinary Medicine, Jilin University, Changchun, Jilin 130062, People's Republic of China
| | - Ankang Mao
- College of Food Science and Engineering, Jilin University, Changchun, Jilin 130062, People's Republic of China
| | - Ranran Zhang
- College of Food Science and Engineering, Jilin University, Changchun, Jilin 130062, People's Republic of China
| | - Shuang Guan
- College of Food Science and Engineering, Jilin University, Changchun, Jilin 130062, People's Republic of China
- Key Laboratory of Zoonosis, Ministry of Education College of Veterinary Medicine, Jilin University, Changchun, Jilin 130062, People's Republic of China
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Zhang YP, Yang XQ, Yu DK, Xiao HY, Du JR. Nrf2 signalling pathway and autophagy impact on the preventive effect of green tea extract against alcohol-induced liver injury. J Pharm Pharmacol 2021; 73:986-995. [PMID: 33877365 DOI: 10.1093/jpp/rgab027] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2020] [Accepted: 02/04/2021] [Indexed: 02/05/2023]
Abstract
OBJECTIVES To explore the potential molecular mechanism underlying the effect of green tea extract (TE), rich in tea polyphenols (TPs), on improving alcohol-induced liver injury. METHODS Mice were intragastrically treated with 50% (v/v) alcohol administration (15 ml/kg BW) with or without three doses of TE (50, 120 and 300 mg TPs/kg BW) daily for 4 weeks, and biological changes were tested. KEY FINDINGS The TE improved the functional and histological situations in the liver of the mice accepted alcohol administration, including enzymes for alcohol metabolism, oxidative stress and lipid accumulation. Interestingly, the TE increased the nuclear translocation of nuclear factor erythroid-2-related factor 2 (Nrf2), with the decreasing expression of kelch-like ECH-associated protein 1 (Keap1), indicating the association between the effect of TE with Nrf2-mediated antioxidant signalling. Moreover, the TE restored the activity of autophagy, showing as lifted Beclin-1 expression, LC3B-II/LC3B-I ratio, and decreased p62 expression. Importantly, all these effects were dose-dependent. CONCLUSIONS These findings provide a new notion for the first time that the TE preventing against alcohol-induced liver injury is closely related to accelerated metabolism of alcohol and relieved oxidative stress, which is associated with Nrf2 signalling activation and autophagy restoration, thus the reduction of lipid accumulation in liver.
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Affiliation(s)
- Yu-Pei Zhang
- Department of Pharmacology, Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial Technology, Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry and Sichuan Province, West China School of Pharmacy, Sichuan University, Chengdu, China
| | - Xue-Qin Yang
- Department of Pharmacology, Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial Technology, Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry and Sichuan Province, West China School of Pharmacy, Sichuan University, Chengdu, China
| | - Dong-Ke Yu
- Department of Pharmacy, Sichuan Provincial People's Hospital, Chengdu, China
| | - Heng-Yi Xiao
- Laboratory of Aging Research, West China Hospital, Sichuan University, Chengdu, China
| | - Jun-Rong Du
- Department of Pharmacology, Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial Technology, Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry and Sichuan Province, West China School of Pharmacy, Sichuan University, Chengdu, China
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Salehi E, Mashayekh M, Taheri F, Gholami M, Motaghinejad M, Safari S, Sepehr A. Curcumin Can be Acts as Effective agent for Prevent or Treatment of Alcohol-induced Toxicity in Hepatocytes: An Illustrated Mechanistic Review. IRANIAN JOURNAL OF PHARMACEUTICAL RESEARCH : IJPR 2021; 20:418-436. [PMID: 34400970 PMCID: PMC8170768 DOI: 10.22037/ijpr.2020.112852.13985] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Previous studies have shown that alcohol abuse can cause serious liver damage and cirrhosis. The main pathway for these types of hepatocellular cell neurodegeneration is mitochondrial dysfunction, which causes lipid peroxidation and dysfunction of the glutathione ring and the defect of antioxidant enzymes in alcoholic hepatic cells. Alcohol can also initiate malicious inflammatory pathways and trigger the initiation and activation of intestinal and extrinsic apoptosis pathways in hepatocellular tissues that lead to cirrhosis. Previous studies have shown that curcumin may inhibit lipid peroxidation, glutathione dysfunction and restore antioxidant enzymes. Curcumin also modulates inflammation and the production of alcohol-induced biomarkers. Curcumin has been shown to play a critical role in the survival of alcoholic hepatocellular tissue. It has been shown that curcumin can induce and trigger mitochondrial biogenesis and, by this mechanism, prevent the occurrence of both intrinsic and extrinsic apoptosis pathways in liver cells that have been impaired by alcohol. According to this mechanism, curcumin may protect hepatocellular tissue from alcohol-induced cell degeneration and may therefore survive alcoholic hepatocellular tissue. . Based on these mechanisms, the protective functions of curcumin against alcohol-induced cell degeneration due to oxidative stress, inflammation, and apoptosis events in hepatocellular tissue have been recorded. Hence, in this research, we have attempted to evaluate and analyze the main contribution mechanism of curcumin cell defense properties against alcohol-induced hepatocellular damage, according to previous experimental and clinical studies, and in this way we report findings from major studies.
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Affiliation(s)
- Elham Salehi
- Department of Pharmaceutical Chemistry, Faculty of Pharmaceutical Chemistry, Pharmaceutical Sciences Branch, Islamic Azad University (IUAPS), Tehran, Iran.
| | - Mohammad Mashayekh
- Department of Pharmaceutical Chemistry, Faculty of Pharmaceutical Chemistry, Pharmaceutical Sciences Branch, Islamic Azad University (IUAPS), Tehran, Iran.
| | - Fereshteh Taheri
- Razi Drug Research Center, Iran University of Medical Sciences, Tehran, Iran.
| | - Mina Gholami
- Department of Medicinal Chemistry, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran.
| | - Majid Motaghinejad
- Razi Drug Research Center, Iran University of Medical Sciences, Tehran, Iran.
| | - Sepideh Safari
- Razi Drug Research Center, Iran University of Medical Sciences, Tehran, Iran.
| | - Afrah Sepehr
- Razi Drug Research Center, Iran University of Medical Sciences, Tehran, Iran.
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Microbiota reprogramming for treatment of alcohol-related liver disease. Transl Res 2020; 226:26-38. [PMID: 32687975 PMCID: PMC7572584 DOI: 10.1016/j.trsl.2020.07.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Revised: 07/01/2020] [Accepted: 07/13/2020] [Indexed: 02/08/2023]
Abstract
In the past decade knowledge has expanded regarding the importance of the gut microbiota in maintaining intestinal homeostasis and overall health. During this same time, we have also gained appreciation for the role of the gut-liver axis in the development of liver diseases. Alcohol overconsumption is one of the leading causes of liver failure globally. However, not all people with alcohol use disorder progress to advanced stages of liver disease. With advances in technology to investigate the gut microbiome and metabolome, we are now beginning to delineate alcohol's effects on the gut microbiome in relation to liver disease. This review presents our current understanding on the role of the gut microbiota during alcohol exposure, and various therapeutic attempts that have been made to reprogram the gut microbiota with the goal of alleviating alcoholic-related liver disease.
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Yuan F, Xu Y, You K, Zhang J, Yang F, Li YX. Calcitriol alleviates ethanol-induced hepatotoxicity via AMPK/mTOR-mediated autophagy. Arch Biochem Biophys 2020; 697:108694. [PMID: 33232716 DOI: 10.1016/j.abb.2020.108694] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2020] [Revised: 11/04/2020] [Accepted: 11/17/2020] [Indexed: 12/28/2022]
Abstract
Excessive ethanol consumption causes cellular damage, leading to fetal alcohol syndrome and alcohol liver diseases, which are frequently seen with vitamin D (VD) deficiency. A great deal of progress has been achieved in the mechanisms of ethanol-induced hepatocyte damage. However, there are limited intervention means to reduce or rescue hepatocytes damage caused by ethanol. On the basis of our preliminary limited screen process, calcitriol showed a positive effect on protecting hepatocyte viability. Therefore, the molecular basis is worth elucidating. We found that calcitriol pretreatment markedly improved the cell viability, decreased cell apoptosis and oxidative stress and alleviated the abnormal mitochondrial morphology and membrane potential of hepatocytes induced by ethanol. Notably, autophagy was significantly enhanced by calcitriol, as evident by the increasing number of autophagosomes and autolysosomes, upregulated LC3B-Ⅱ and ATG5 levels, and promotion of p62 degradation. Furthermore, calcitriol pretreatment increased the colocalization of GFP-LC3-labeled autophagosomes with mitochondria, suggesting that calcitriol effectively promoted ethanol-induced mitophagy in hepatocytes. In addition, the inhibition of autophagy attenuated the protective and preventive effect of calcitriol. Furthermore, the effect of calcitriol on autophagy was regulated by AMPK/mTOR signaling, and signaling transduction was dependent on the Vitamin D receptor (VDR). In conclusion, calcitriol ameliorates ethanol-induced hepatocyte damage by enhancing autophagy. It may offer a convenient preventive and hepatoprotective mean for people on occasional social drink.
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Affiliation(s)
- Fang Yuan
- School of Life Sciences, University of Science and Technology of China, 230027, Hefei, China; Institute of Public Health, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, 510530, Guangzhou, China; Key Laboratory of Regenerative Biology, South China Institute for Stem Cell Biology and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, 510530, Guangzhou, China; Guangdong Provincial Key Laboratory of Biocomputing, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, 510530, Guangzhou, China
| | - Yingying Xu
- Institute of Public Health, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, 510530, Guangzhou, China; Key Laboratory of Regenerative Biology, South China Institute for Stem Cell Biology and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, 510530, Guangzhou, China; Guangdong Provincial Key Laboratory of Biocomputing, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, 510530, Guangzhou, China
| | - Kai You
- Institute of Public Health, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, 510530, Guangzhou, China; Key Laboratory of Regenerative Biology, South China Institute for Stem Cell Biology and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, 510530, Guangzhou, China; Guangdong Provincial Key Laboratory of Biocomputing, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, 510530, Guangzhou, China
| | - Jiaye Zhang
- Institute of Public Health, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, 510530, Guangzhou, China; Key Laboratory of Regenerative Biology, South China Institute for Stem Cell Biology and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, 510530, Guangzhou, China; Guangdong Provincial Key Laboratory of Biocomputing, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, 510530, Guangzhou, China
| | - Fan Yang
- Institute of Public Health, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, 510530, Guangzhou, China; Key Laboratory of Regenerative Biology, South China Institute for Stem Cell Biology and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, 510530, Guangzhou, China; Guangdong Provincial Key Laboratory of Biocomputing, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, 510530, Guangzhou, China
| | - Yin-Xiong Li
- Institute of Public Health, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, 510530, Guangzhou, China; Key Laboratory of Regenerative Biology, South China Institute for Stem Cell Biology and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, 510530, Guangzhou, China; Guangdong Provincial Key Laboratory of Biocomputing, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, 510530, Guangzhou, China.
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12
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Kurhaluk N, Tkachenko H, Lukash O. Melatonin modulates oxidative phosphorylation, hepatic and kidney autophagy-caused subclinical endotoxemia and acute ethanol-induced oxidative stress. Chronobiol Int 2020; 37:1709-1724. [DOI: 10.1080/07420528.2020.1830792] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- Natalia Kurhaluk
- Department of Zoology and Animal Physiology, Institute of Biology and Earth Sciences, Pomeranian University in Słupsk, Słupsk, Poland
| | - Halyna Tkachenko
- Department of Zoology and Animal Physiology, Institute of Biology and Earth Sciences, Pomeranian University in Słupsk, Słupsk, Poland
| | - Oleksandr Lukash
- Department of Ecology and Nature Protection, T.G. Shevchenko National University “Chernihiv Collegium”, Chernihiv, Ukraine
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13
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Fan J, Shi Y, Peng Y. Autophagy and Liver Diseases. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2020; 1207:497-528. [PMID: 32671772 DOI: 10.1007/978-981-15-4272-5_37] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Autophagy plays an important role in the physiology and pathology of the liver. It is involved in the development of many liver diseases such as α-1-antitrypsin deficiency, chronic hepatitis virus infection, alcoholic liver disease, nonalcoholic fatty liver disease, and liver cancer. Autophagy has thus become a new target for the treatment of liver diseases. How to treat liver diseases by regulating autophagy has been a hot topic.
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Affiliation(s)
- Jia Fan
- Zhongshan Hospital, Fudan University, 180 FengLin Road, Shanghai, China.
| | - Yinghong Shi
- Zhongshan Hospital, Fudan University, 180 FengLin Road, Shanghai, China
| | - Yuanfei Peng
- Zhongshan Hospital, Fudan University, 180 FengLin Road, Shanghai, China
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14
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Ma Y, Chai H, Ding Q, Qian Q, Yan Z, Ding B, Dou X, Li S. Hepatic SIRT3 Upregulation in Response to Chronic Alcohol Consumption Contributes to Alcoholic Liver Disease in Mice. Front Physiol 2019; 10:1042. [PMID: 31474877 PMCID: PMC6707764 DOI: 10.3389/fphys.2019.01042] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2019] [Accepted: 07/30/2019] [Indexed: 12/20/2022] Open
Abstract
Background Alcoholic liver disease (ALD) is a type of chronic liver disease caused by chronic ethanol overconsumption. The pathogenesis of ALD is complex and there is no effective clinical treatment thus far. SIRT3 is an NAD+-dependent deacetylase primarily located inside mitochondria, and reports on the effect of chronic alcohol exposure on liver SIRT3 expression are scarce. This study aims to investigate the effect of chronic alcohol consumption on hepatic SIRT3 expression and its role in alcoholic-induced liver injury. Methods Using the Lieber-DeCarli mouse model of ALD, we analyzed the regulation of SIRT3 and the effect of liver-specific knocking-down of SIRT3 on alcohol-induced liver injury. HepG2 and AML12 hepatocytes were employed to detect the biological function of SIRT3 on alcohol-induced hepatic cytotoxicity and its potential mechanism. Results Chronic alcohol exposure led to hepatic SIRT3 upregulation and liver-specific SIRT3 knockdown alleviated alcoholic feeding-induced liver injury and lipid accumulation, which is associated with improved autophagy induction. In addition, autophagy induction contributed to the cytoprotective effect of SIRT3 knockdown on ethanol-induced hepatocyte cell death. Conclusion In summary, our data suggest that hepatic SIRT3 upregulation in response to chronic alcohol exposure and liver-specific SIRT3 knockdown, induced autophagy activation further alleviating alcoholic-induced liver injury, which represents a novel mechanism in this process.
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Affiliation(s)
- Yue Ma
- College of Life Sciences, Zhejiang Chinese Medical University, Hangzhou, China.,Laboratory Animal Center, Zhejiang Academy of Medical Sciences, Hangzhou, China
| | - Hui Chai
- College of Life Sciences, Zhejiang Chinese Medical University, Hangzhou, China.,Molecular Medicine Institute, Zhejiang Chinese Medical University, Hangzhou, China
| | - Qinchao Ding
- College of Life Sciences, Zhejiang Chinese Medical University, Hangzhou, China
| | - Qianyu Qian
- College of Life Sciences, Zhejiang Chinese Medical University, Hangzhou, China
| | - Zhaoyuan Yan
- College of Life Sciences, Zhejiang Chinese Medical University, Hangzhou, China
| | - Bin Ding
- College of Life Sciences, Zhejiang Chinese Medical University, Hangzhou, China.,Molecular Medicine Institute, Zhejiang Chinese Medical University, Hangzhou, China
| | - Xiaobing Dou
- College of Life Sciences, Zhejiang Chinese Medical University, Hangzhou, China.,Molecular Medicine Institute, Zhejiang Chinese Medical University, Hangzhou, China
| | - Songtao Li
- Molecular Medicine Institute, Zhejiang Chinese Medical University, Hangzhou, China.,College of Basic Medicine and Public Health, Zhejiang Chinese Medical University, Hangzhou, China
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15
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Atef MM, Hafez YM, Alshenawy HA, Emam MN. Ameliorative effects of autophagy inducer, simvastatin on alcohol-induced liver disease in a rat model. J Cell Biochem 2019; 120:7679-7688. [PMID: 30417426 DOI: 10.1002/jcb.28042] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2018] [Accepted: 10/22/2018] [Indexed: 01/24/2023]
Abstract
Alcoholic liver disease (ALD) encompasses a variety of liver injuries with various underlying mechanisms but still no effective treatment. So we aimed to monitor the influence of simvastatin on alcohol-induced liver injury and elucidate the underlying mechanisms of its cytoprotective effect. Thirty male albino rats were randomly divided into five equal groups. Group 1 (control): received a standard diet; group 2: received simvastatin (10 mg kg-1 day -1 ) once a day orally for 8 weeks; group 3: received 20% ethanol (7.9 g kg -1 day -1 ) daily orally for 8 weeks; group 4: received 20% ethanol along with same simvastatin dose daily for 8 weeks; group 5: received 20% ethanol orally for 8 weeks then received the same simvastatin dose for the next 8 weeks. Serum alanine aminotransferase, aspartate aminotransferase, total cholesterol, triglycerides, high-density lipoprotein cholesterol, and low-density lipoprotein cholesterol were measured. Liver tissue malondialdehyde, reduced glutathione levels, and superoxide dismutase activity were estimated. B-cell lymphoma 2 and C/EBP homologous protein levels were evaluated by enzyme linked immunosorbent assay (ELISA). Light chain 3-II and peroxisome proliferation-activated receptor gamma messenger RNA expression was assessed by real-time polymerase chain reaction. Immunohistochemical staining was performed using anti-rat tumor necrosis factor-alpha antibody. Our results revealed that simvastatin treatment was able to ameliorate alcohol-induced liver damage; the improved biochemical data were confirmed by histopathological evaluation. Simvastatin being an autophagy inducer was able to prevent and reverse alcohol-induced liver changes via induction of autophagy, attenuation of oxidative stress, inflammation, and endoplasmic reticulum stress-induced apoptosis. Therefore, our findings suggest that treatment with simvastatin may be a useful approach in the management strategy of ALD.
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Affiliation(s)
- Marwa Mohamed Atef
- Medical Biochemistry Department, Faculty of Medicine, Tanta University, Tanta, Egypt
| | - Yasser Mostafa Hafez
- Internal Medicine Department, Faculty of Medicine, Tanta University, Tanta, Egypt
| | | | - Marwa Nagy Emam
- Physiology Department, Faculty of Medicine, Tanta University, Tanta, Egypt
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16
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Ramesh J, Ronsard L, Gao A, Venugopal B. Autophagy Intertwines with Different Diseases-Recent Strategies for Therapeutic Approaches. Diseases 2019; 7:diseases7010015. [PMID: 30717078 PMCID: PMC6473623 DOI: 10.3390/diseases7010015] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2018] [Revised: 01/22/2019] [Accepted: 01/28/2019] [Indexed: 12/12/2022] Open
Abstract
Autophagy is a regular and substantial “clear-out process” that occurs within the cell and that gets rid of debris that accumulates in membrane-enclosed vacuoles by using enzyme-rich lysosomes, which are filled with acids that degrade the contents of the vacuoles. This machinery is well-connected with many prevalent diseases, including cancer, HIV, and Parkinson’s disease. Considering that autophagy is well-known for its significant connections with a number of well-known fatal diseases, a thorough knowledge of the current findings in the field is essential in developing therapies to control the progression rate of diseases. Thus, this review summarizes the critical events comprising autophagy in the cellular system and the significance of its key molecules in manifesting this pathway in various diseases for down- or upregulation. We collectively reviewed the role of autophagy in various diseases, mainly neurodegenerative diseases, cancer, inflammatory diseases, and renal disorders. Here, some collective reports on autophagy showed that this process might serve as a dual performer: either protector or contributor to certain diseases. The aim of this review is to help researchers to understand the role of autophagy-regulating genes encoding functional open reading frames (ORFs) and its connection with diseases, which will eventually drive better understanding of both the progression and suppression of different diseases at various stages. This review also focuses on certain novel therapeutic strategies which have been published in the recent years based on targeting autophagy key proteins and its interconnecting signaling cascades.
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Affiliation(s)
- Janani Ramesh
- Department of Medical Biochemistry, Dr. A.L.M. Post Graduate Institute of Basic Medical Sciences, University of Madras, Chennai 600113, India.
- Renal Division, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA.
| | - Larance Ronsard
- The Ragon Institute of Massachusetts General Hospital, The Massachusetts Institute of Technology and Harvard University, 400 Technology Square, Cambridge, MA 02140, USA.
| | - Anthony Gao
- Renal Division, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA.
| | - Bhuvarahamurthy Venugopal
- Department of Medical Biochemistry, Dr. A.L.M. Post Graduate Institute of Basic Medical Sciences, University of Madras, Chennai 600113, India.
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17
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Guan ZF, Zhang XM, Tao YH, Zhang Y, Huang YY, Chen G, Tang WJ, Ji G, Guo QL, Liu M, Zhang Q, Wang NN, Yu ZY, Wu GF, Tang ZP, Du ZG, Shang XL, Liu YC, Mei GH, Guo JC, Zhou HG. EGb761 improves the cognitive function of elderly db/db -/- diabetic mice by regulating the beclin-1 and NF-κB signaling pathways. Metab Brain Dis 2018; 33:1887-1897. [PMID: 30187180 PMCID: PMC6244769 DOI: 10.1007/s11011-018-0295-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/05/2017] [Accepted: 07/23/2018] [Indexed: 12/23/2022]
Abstract
To assess whether EGb761 could protect elderly diabetic mice with cognitive disorders and explore the role of beclin-1-mediated autophagy in these protective effects. Two-month-old male db/db-/- mice and wild-type C57/BL6 mice were randomly divided into six groups: db/db-/- control, db/db-/- 50 mg, db/db-/- 100 mg, wild-type (WT) control, WT 50 mg, and WT 100 mg. EGb761 (50 mg/kg or 100 mg/kg of bodyweight) was given by gavage once a day for 1 month from the age of 6 months. Y-maze and social choice tests were performed at 8th months. The blood pressure was measured. The imaging changes in the brain were measured using magnetic resonance imaging (MRI). The expression and distribution of beclin-1, LC3, and NF-κB were detected using immunohistochemistry staining and western blotting. Ultrastructure alterations in the hippocampus were observed using transmission electron microscopy. Compared with WT mice, the learning ability, memory and overall cognitive function of db/db-/- mice decreased (P < 0.05), and EGb761 could significantly improve the learning and memory function of db/db-/- mice (P < 0.05). EGb761 significantly improved systolic blood pressure in db/db-/- mice (P < 0.01). In addition, fMRI-bold showed a decline in the hippocampus of mice in the db/db-/- group compared with WT. EGb761 could improve these above changes. Immunohistochemistry staining and western blotting confirmed that EGb761 significantly increased beclin-1 and reduced LC3-II/I levels in the brains of db/db-/- mice (P < 0.05). NF-κB levels were obviously higher in the db/db-/- group than that in the WT group, and EGb761 significantly reduced NF-κB levels in db/db-/- mice (P < 0.05). There was a trend of increased autophagosomes in db/db-/- mice, but EGb761 did not change obviously the number of autophagosomes. Compared with normal aged WT mice, aging db/db-/- mice had more common complications of cerebral small vessel disease and cognitive dysfunction. EGb761 could significantly improve the cognitive function of aging db/db-/- mice via a mechanism that may involve the regulation of beclin-1, LC3, and NF-κB.
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Affiliation(s)
- Zhu-Fei Guan
- Department of Geriatrics, National Clinical Research Center for Aging and Medicine, Huashan Hospital, Fudan University, Shanghai, 200040, China
- State Key Laboratory of Medical Neurobiology, Department of Neurobiology, School of Basic Medical Neurobiology, Department of Neurobiology School of Basic Medical Science, Shanghai Medical College, Fudan University, Shanghai, 200032, China
| | - Xiao-Ming Zhang
- Department of Geriatrics, National Clinical Research Center for Aging and Medicine, Huashan Hospital, Fudan University, Shanghai, 200040, China
| | - Ying-Hong Tao
- Department of Medical Examination Center, Huashan Hospital, Fudan University, Shanghai, 200040, China
| | - Yu Zhang
- Department of Geriatrics, National Clinical Research Center for Aging and Medicine, Huashan Hospital, Fudan University, Shanghai, 200040, China
| | - Yan-Yan Huang
- Department of Geriatrics, National Clinical Research Center for Aging and Medicine, Huashan Hospital, Fudan University, Shanghai, 200040, China
| | - Gang Chen
- Department of Geriatrics, National Clinical Research Center for Aging and Medicine, Huashan Hospital, Fudan University, Shanghai, 200040, China
| | - Wei-Jun Tang
- Department of Radiology, Huashan Hospital, Fudan University, Shanghai, 200040, China
| | - Gang Ji
- State Key Laboratory of Medical Neurobiology, Department of Neurobiology, School of Basic Medical Neurobiology, Department of Neurobiology School of Basic Medical Science, Shanghai Medical College, Fudan University, Shanghai, 200032, China
| | - Qi-Lin Guo
- State Key Laboratory of Medical Neurobiology, Department of Neurobiology, School of Basic Medical Neurobiology, Department of Neurobiology School of Basic Medical Science, Shanghai Medical College, Fudan University, Shanghai, 200032, China
| | - Ming Liu
- State Key Laboratory of Medical Neurobiology, Department of Neurobiology, School of Basic Medical Neurobiology, Department of Neurobiology School of Basic Medical Science, Shanghai Medical College, Fudan University, Shanghai, 200032, China
| | - Qian Zhang
- State Key Laboratory of Medical Neurobiology, Department of Neurobiology, School of Basic Medical Neurobiology, Department of Neurobiology School of Basic Medical Science, Shanghai Medical College, Fudan University, Shanghai, 200032, China
| | - Na-Na Wang
- Department of Geriatrics, National Clinical Research Center for Aging and Medicine, Huashan Hospital, Fudan University, Shanghai, 200040, China
| | - Zhong-Yu Yu
- Department of Geriatrics, National Clinical Research Center for Aging and Medicine, Huashan Hospital, Fudan University, Shanghai, 200040, China
| | - Guo-Feng Wu
- Department of Emergency Neurology, Guiyang Medical University, Guiyang, 550004, China
| | - Zhou-Ping Tang
- Department of Neurology, Tongji Hospital, Huazhong University of Science and Technology, Wuhan, 430000, China
| | - Zun-Guo Du
- Department of Pathology, Huashan Hospital, Fudan University, Shanghai, 200040, China
| | - Xi-Liang Shang
- Department of Sport Medicine, Huashan Hospital, Fudan University, Shanghai, 200040, China
| | - Ying-Chao Liu
- Department of Neurosurgery, Provincial Hospital Affiliated to Shandong University, Jinan, 250021, China
| | - Guang-Hai Mei
- Department of Neurosurgery, Huashan Hospital, Fudan University, Shanghai, 200040, China.
| | - Jing-Chun Guo
- State Key Laboratory of Medical Neurobiology, Department of Neurobiology, School of Basic Medical Neurobiology, Department of Neurobiology School of Basic Medical Science, Shanghai Medical College, Fudan University, Shanghai, 200032, China.
| | - Hou-Guang Zhou
- Department of Geriatrics, National Clinical Research Center for Aging and Medicine, Huashan Hospital, Fudan University, Shanghai, 200040, China.
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18
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Yin XM. Autophagy in liver diseases: A matter of what to remove and whether to keep. LIVER RESEARCH 2018; 2:109-111. [PMID: 32042470 PMCID: PMC7010265 DOI: 10.1016/j.livres.2018.09.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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19
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Sun J, Fu J, Li L, Chen C, Wang H, Hou Y, Xu Y, Pi J. Nrf2 in alcoholic liver disease. Toxicol Appl Pharmacol 2018; 357:62-69. [PMID: 30165058 DOI: 10.1016/j.taap.2018.08.019] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2018] [Revised: 08/23/2018] [Accepted: 08/24/2018] [Indexed: 12/19/2022]
Abstract
Alcoholic liver disease (ALD) is a leading cause of morbidity and mortality of liver disorders and a major health issue globally. ALD refers to a spectrum of liver pathologies ranging from steatosis, steatohepatitis, fibrosis, cirrhosis and even hepatocellular carcinoma. Various mechanisms, including oxidative stress, protein and DNA modification, inflammation and impaired lipid metabolism, have been implicated in the pathogenesis of ALD. Further, reactive oxygen species (ROS) in particular, have been identified as a key component in the initiation and progression of ALD. Nuclear factor erythroid 2 like 2 (Nrf2) is a master regulator of the intracellular adaptive antioxidant response to oxidative stress, and aids in the detoxification of a variety of toxicants. Given its cytoprotective role, Nrf2 has been extensively studied as a therapeutic target for ALD. Paradoxically, however, emerging evidence have revealed that Nrf2 may be implicated in the progression of ALD. In this review, we summarize the role of Nrf2 in the development of ALD and discuss the underlying mechanisms. Clearly, more comprehensive studies with proper animal and cell models and in human are needed to verify the potential therapeutic role of Nrf2 in ALD.
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Affiliation(s)
- Jing Sun
- Program of Environmental Toxicology, School of Public Health, China Medical University, No. 77 Puhe Road, Shenyang North New Area, Shenyang, Liaoning 110122, PR China
| | - Jingqi Fu
- Program of Environmental Toxicology, School of Public Health, China Medical University, No. 77 Puhe Road, Shenyang North New Area, Shenyang, Liaoning 110122, PR China.
| | - Lu Li
- Program of Environmental Toxicology, School of Public Health, China Medical University, No. 77 Puhe Road, Shenyang North New Area, Shenyang, Liaoning 110122, PR China
| | - Chengjie Chen
- Program of Environmental Toxicology, School of Public Health, China Medical University, No. 77 Puhe Road, Shenyang North New Area, Shenyang, Liaoning 110122, PR China
| | - Huihui Wang
- Group of Chronic Disease and Environmental Genomics, School of Public Health, China Medical University, No. 77 Puhe Road, Shenyang North New Area, Shenyang, Liaoning 110122, PR China
| | - Yongyong Hou
- Program of Environmental Toxicology, School of Public Health, China Medical University, No. 77 Puhe Road, Shenyang North New Area, Shenyang, Liaoning 110122, PR China
| | - Yuanyuan Xu
- Group of Chronic Disease and Environmental Genomics, School of Public Health, China Medical University, No. 77 Puhe Road, Shenyang North New Area, Shenyang, Liaoning 110122, PR China
| | - Jingbo Pi
- Program of Environmental Toxicology, School of Public Health, China Medical University, No. 77 Puhe Road, Shenyang North New Area, Shenyang, Liaoning 110122, PR China.
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20
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Bak DH, Na J, Choi MJ, Lee BC, Oh CT, Kim JY, Han HJ, Kim MJ, Kim TH, Kim BJ. Anti‑apoptotic effects of human placental hydrolysate against hepatocyte toxicity in vivo and in vitro. Int J Mol Med 2018; 42:2569-2583. [PMID: 30132515 PMCID: PMC6192762 DOI: 10.3892/ijmm.2018.3830] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2018] [Accepted: 07/30/2018] [Indexed: 02/07/2023] Open
Abstract
Apoptosis and oxidative stress are essential for the pathogenesis of acute liver failure and fulminant hepatic failure. Human placental hydrolysate (hPH) has been reported to possess antioxidant and anti-inflammatory properties. In the present study, the protective effects of hPH against D-galactosamine (D-GalN)- and lipopolysaccharide (LPS)-induced hepatocyte apoptosis were investigated in vivo. In addition, the molecular mechanisms underlying the anti-apoptotic activities of hPH against D-GalN-induced cell death in vitro were examined. Male Sprague-Dawley rats were injected with D-GaIN/LPS with or without the administration of hPH. Rats were sacrificed 24 h after D-GaIN/LPS intraperitoneal injection, and the blood and liver samples were collected for future inflammation and hepatotoxicity analyses. Changes in cell viability, apoptosis protein expression, mitochondrial mass, mitochondrial membrane potential, reactive oxygen species generation, and the levels of proteins and mRNA associated with a protective mechanism were determined in HepG2 cells pretreated with hPH for 2 h prior to D-GalN exposure. The findings suggested that hPH treatment effectively protected against D-GalN/LPS-induced hepatocyte apoptosis by reducing the levels of alanine aminotransferase, aspartate aminotransferase, lactate dehydrogenase, interleukin-6, and tumor necrosis factor-α, and increasing the level of proliferating cell nuclear antigen. It was also found that hPH inhibited the apoptotic cell death induced by D-GalN. hPH activated the expression of antioxidant enzymes, including superoxide dismutase, glutathione peroxidase, and catalase, which were further upregulated by the Kelch-like ECH2-associated protein 1-p62-nuclear factor-erythroid 2-related factor 2 pathway, a component of oxidative stress defense mechanisms. Furthermore, hPH markedly reduced cytosolic and mitochondrial reactive oxygen species and rescued mitochondrial loss and dysfunction through the reduction of damage-regulated autophagy modulator, p53, and C/EBP homologous protein. Collectively, hPH exhibited a protective role in hepatocyte apoptosis by inhibiting oxidative stress and maintaining cell homeostasis. The underlying mechanisms may be associated with the inhibition of endoplasmic reticulum stress and minimization of the autophagy progress.
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Affiliation(s)
- Dong-Ho Bak
- Department of Dermatology, College of Medicine, Chung‑Ang University, Seoul 06973, Republic of Korea
| | - Jungtae Na
- Department of Dermatology, College of Medicine, Chung‑Ang University, Seoul 06973, Republic of Korea
| | - Mi Ji Choi
- Department of Dermatology, College of Medicine, Chung‑Ang University, Seoul 06973, Republic of Korea
| | - Byung Chul Lee
- Department of Dermatology, College of Medicine, Chung‑Ang University, Seoul 06973, Republic of Korea
| | - Chang Taek Oh
- Research and Development Center, Green Cross WellBeing Corporation, Seongnam, Gyeonggi 13595, Republic of Korea
| | - Jeom-Yong Kim
- Research and Development Center, Green Cross WellBeing Corporation, Seongnam, Gyeonggi 13595, Republic of Korea
| | - Hae Jung Han
- Research and Development Center, Green Cross WellBeing Corporation, Seongnam, Gyeonggi 13595, Republic of Korea
| | | | - Tae Ho Kim
- Division of Gastroenterology, Department of Internal Medicine, Bucheon St. Mary's Hospital, The Catholic University of Korea, Bucheon‑si, Gyeonggi 14647, Republic of Korea
| | - Beom Joon Kim
- Department of Dermatology, College of Medicine, Chung‑Ang University, Seoul 06973, Republic of Korea
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Chung HH. The Multiple Modulation of miR-122 in the Attenuation of Alcoholic Liver Disease. Gastroenterology 2018; 154:1857. [PMID: 29621515 DOI: 10.1053/j.gastro.2018.02.036] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/25/2018] [Accepted: 02/09/2018] [Indexed: 12/19/2022]
Affiliation(s)
- Hsien-Hui Chung
- Preventive Medicine Program, Center for General Education, Chung Yuan Christian University, Taoyuan City, Taiwan and Department of Pharmacy & Clinical Trial Pharmacy, Kaohsiung Veterans General Hospital, Kaohsiung City, Taiwan
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22
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Activation of autophagy attenuates EtOH-LPS-induced hepatic steatosis and injury through MD2 associated TLR4 signaling. Sci Rep 2017; 7:9292. [PMID: 28839246 PMCID: PMC5571015 DOI: 10.1038/s41598-017-09045-z] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2017] [Accepted: 07/17/2017] [Indexed: 12/13/2022] Open
Abstract
Autophagy serves as a protective mechanism to degrade damaged organelles and proteins. Acute alcohol exposure is known to activate the hepatic autophagy response, whereas chronic alcohol exposure slows autophagosome formation along with an elevation of gut-derived endotoxin. In the current study, we examined whether lipopolysaccharide (LPS) administration decreased autophagic response in the liver of mice treated by short-term alcohol and whether activation of autophagy by rapamycin attenuates EtOH-LPS-induced liver steatosis and injury. We demonstrated that ten-day alcohol feeding primed the liver to LPS-induced lipid accumulation and liver injury with significantly increased hepatic steatosis and serum AST level as well as hepatic cellular NF-κB activation. LPS increased alcohol-mediated reactive oxygen species (ROS) formation while reducing autophagy activation. These deleterious effects were attenuated by rapamycin administration in mice. The protective effects of rapamycin are associated with decreased cellular MD2/TLR4 expression and interaction in Raw264.7 cells. Taken together, our results demonstrated that enhanced gut-derived LPS decreases the hepatic autophagosome numbers in response to alcohol exposure, and activation of autophagy by rapamycin protects from EtOH-LPS-induced liver injury, probably through reduced macrophage expression and interaction of TLR4/MD2 signaling complex.
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Guan Z, Tao Y, Zhang X, Guo Q, Liu Y, Zhang Y, Wang Y, ji G, Wu G, Wang N, Yang H, Yu Z, Guo J, Zhou H. G-CSF and cognitive dysfunction in elderly diabetic mice with cerebral small vessel disease: Preventive intervention effects and underlying mechanisms. CNS Neurosci Ther 2017; 23:462-474. [PMID: 28374506 PMCID: PMC6492719 DOI: 10.1111/cns.12691] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2017] [Revised: 02/25/2017] [Accepted: 02/27/2017] [Indexed: 12/23/2022] Open
Abstract
AIMS Although cognitive dysfunction is a common neurological complication in elderly patients with diabetes, the mechanisms underlying this relationship remain unclear, and effective preventive interventions have yet to be developed. Thus, this study investigated the preventive effects and mechanisms of action associated with granulocyte colony-stimulating factor (G-CSF) on cognitive dysfunction in elderly diabetic mice with cerebral small vessel disease. METHODS This study included 40 male db/db diabetic and wild-type (WT) mice that were categorized into the following four groups at the age of 3 weeks: db/db group (DG), db/db+G-CSF group (DGG), WT group (WG), and WT+G-CSF group (WGG). The mice were fed normal diets for 4 months and then given G-CSF (75 μg/kg) via intraperitoneal injections for 1 month. At 7.5 months of age, the cognitive abilities of the mice were assessed with the Y-maze test and the Social Choice Test; body weight, blood pressure (BP), and blood glucose measurements were obtained throughout the study. Brain imaging and blood oxygen level-dependent (BOLD) contrast imaging analyses were performed with a small animal magnetic resonance imaging (MRI) system, autophagosome levels were detected with a transmission electron microscope (TEM), hippocampal neurons were assessed with hematoxylin and eosin (HE) staining, and protein expressions and distributions were evaluated using immunohistochemistry and Western blot analyses. RESULTS (i) The body weight and blood glucose levels of the DG and DGG mice were significantly higher than those of the WG and WGG mice; (ii) social choice and spatial memory capabilities were significantly reduced in DG mice but were recovered by G-CSF in DGG mice; (iii) the MRI scans revealed multiple lacunar lesions and apparent hippocampal atrophy in the brains of DG mice, but G-CSF reduced the number of lacunar lesions and ameliorated hippocampal atrophy; (iv) the MRI-BOLD scans showed a downward trend in whole-brain activity and reductions in the connectivities of the hippocampus and amygdala with subcortical structures in DG mice, but G-CSF clearly improved the altered brain activity as well as the connectivity of the hippocampus in DGG mice; (v) HE staining revealed fewer neurons in the hippocampus in DG mice; (vi) TEM analyses revealed significantly fewer autophagosomes in the hippocampi of DG mice, but G-CSF did not increase these numbers; (vii) there were significant reductions in mechanistic target of rapamycin (mTOR) and LC3-phosphatidylethanolamine conjugate (LC3)-II/I levels in the hippocampi of DG mice, whereas p62 was upregulated, and G-CSF significantly enhanced the levels of Beclin1, mTOR, and LC-II/I in DGG mice; and (viii) G-CSF significantly reversed increases in nuclear factor κB (NF-κB) protein levels in DG but not in WG mice. CONCLUSIONS In this study, aged diabetic mice were prone to cognitive dysfunction and cerebral small vessel disease. However, administration of G-CSF significantly improved cognitive function in elderly db/db diabetic mice, and this change was likely related to the regulation of autophagy and NF-κB signaling pathways.
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Affiliation(s)
- Zhu‐Fei Guan
- Department of Geriatric NeurologyHuashan HospitalFudan UniversityShanghaiChina
- State Key Laboratory of Medical NeurobiologyInstitute of Brain ScienceFudan UniversityShanghaiChina
| | - Ying‐Hong Tao
- Department of General MedicineOuyang Community Health Service CenterHongkou DistrictShanghaiChina
| | - Xiao‐Ming Zhang
- Department of Geriatric NeurologyHuashan HospitalFudan UniversityShanghaiChina
| | - Qi‐Lin Guo
- State Key Laboratory of Medical NeurobiologyInstitute of Brain ScienceFudan UniversityShanghaiChina
| | - Ying‐Chao Liu
- Department of NeurosurgeryShandong Provincial HospitalJinanChina
| | - Yu Zhang
- Department of Geriatric NeurologyHuashan HospitalFudan UniversityShanghaiChina
| | - Yan‐Mei Wang
- Department of Geriatric NeurologyHuashan HospitalFudan UniversityShanghaiChina
| | - Gang ji
- State Key Laboratory of Medical NeurobiologyInstitute of Brain ScienceFudan UniversityShanghaiChina
| | - Guo‐Feng Wu
- Department of Emergency NeurologyAffiliated HospitalGuiyang Medical UniversityGuiyangChina
| | - Na‐Na Wang
- Department of Geriatric NeurologyHuashan HospitalFudan UniversityShanghaiChina
| | - Hao Yang
- Department of Geriatric NeurologyHuashan HospitalFudan UniversityShanghaiChina
| | - Zhong‐Yu Yu
- Department of Geriatric NeurologyHuashan HospitalFudan UniversityShanghaiChina
| | - Jing‐Chun Guo
- State Key Laboratory of Medical NeurobiologyInstitute of Brain ScienceFudan UniversityShanghaiChina
| | - Hou‐Guang Zhou
- Department of Geriatric NeurologyHuashan HospitalFudan UniversityShanghaiChina
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BISPO VANDERSONS, DANTAS LUCASS, CHAVES FILHO ADRIANOB, PINTO ISABELLAF, SILVA RAILMARAPDA, OTSUKA FELIPEA, SANTOS RODRIGOB, SANTOS ALINEC, TRINDADE DANIELLEJ, MATOS HUMBERTOR. Reduction of the DNA damages, Hepatoprotective Effect and Antioxidant Potential of the Coconut Water, ascorbic and Caffeic Acids in Oxidative Stress Mediated by Ethanol. ACTA ACUST UNITED AC 2017; 89:1095-1109. [DOI: 10.1590/0001-3765201720160581] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2016] [Accepted: 01/04/2017] [Indexed: 11/21/2022]
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Schulze RJ, Rasineni K, Weller SG, Schott MB, Schroeder B, Casey CA, McNiven MA. Ethanol exposure inhibits hepatocyte lipophagy by inactivating the small guanosine triphosphatase Rab7. Hepatol Commun 2017; 1:140-152. [PMID: 29404450 PMCID: PMC5721426 DOI: 10.1002/hep4.1021] [Citation(s) in RCA: 52] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/24/2016] [Accepted: 01/29/2017] [Indexed: 12/20/2022] Open
Abstract
Alcohol consumption is a well-established risk factor for the onset and progression of fatty liver disease. An estimated 90% of heavy drinkers are thought to develop significant liver steatosis. For these reasons, an increased understanding of the molecular basis for alcohol-induced hepatic steatosis is important. It has become clear that autophagy, a catabolic process of intracellular degradation and recycling, plays a key role in hepatic lipid metabolism. We have shown that Rab7, a small guanosine triphosphatase known to regulate membrane trafficking, acts as a key orchestrator of hepatocellular lipophagy, a selective form of autophagy in which lipid droplets (LDs) are specifically targeted for turnover by the autophagic machinery. Nutrient starvation results in Rab7 activation on the surface of the LD and lysosomal compartments, resulting in the mobilization of triglycerides stored within the LDs for energy production. Here, we examine whether the steatotic effects of alcohol exposure are a result of perturbations to the Rab7-mediated lipophagic pathway. Rats chronically fed an ethanol-containing diet accumulated significantly higher levels of fat in their hepatocytes. Interestingly, hepatocytes isolated from these ethanol-fed rats contained juxtanuclear lysosomes that exhibited impaired motility. These changes are similar to those we observed in Rab7-depleted hepatocytes. Consistent with these defects in the lysosomal compartment, we observed a marked 80% reduction in Rab7 activity in cultured hepatocytes as well as a complete block in starvation-induced Rab7 activation in primary hepatocytes isolated from chronic ethanol-fed animals. Conclusion: A mechanism is supported whereby ethanol exposure inhibits Rab7 activity, resulting in the impaired transport, targeting, and fusion of the autophagic machinery with LDs, leading to an accumulation of hepatocellular lipids and hepatic steatosis. (Hepatology Communications 2017;1:140-152).
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Affiliation(s)
- Ryan J. Schulze
- Department of Biochemistry and Molecular Biology and the Center for Digestive DiseasesMayo ClinicRochesterMN
| | - Karuna Rasineni
- Department of Internal MedicineUniversity of Nebraska Medical CenterOmahaNE
| | - Shaun G. Weller
- Department of Biochemistry and Molecular Biology and the Center for Digestive DiseasesMayo ClinicRochesterMN
| | - Micah B. Schott
- Department of Biochemistry and Molecular Biology and the Center for Digestive DiseasesMayo ClinicRochesterMN
| | - Barbara Schroeder
- Department of Biochemistry and Molecular Biology and the Center for Digestive DiseasesMayo ClinicRochesterMN
- Present address:
Helmholtz Zentrum München, Institute of Biological and Medical ImagingNeuherbergGermany
| | - Carol A. Casey
- Department of Internal MedicineUniversity of Nebraska Medical CenterOmahaNE
- Research Service, VA Nebraska‐Western Iowa Health Care SystemOmahaNE
| | - Mark A. McNiven
- Department of Biochemistry and Molecular Biology and the Center for Digestive DiseasesMayo ClinicRochesterMN
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Neuman MG, French SW, Zakhari S, Malnick S, Seitz HK, Cohen LB, Salaspuro M, Voinea-Griffin A, Barasch A, Kirpich IA, Thomes PG, Schrum LW, Donohue TM, Kharbanda KK, Cruz M, Opris M. Alcohol, microbiome, life style influence alcohol and non-alcoholic organ damage. Exp Mol Pathol 2017; 102:162-180. [PMID: 28077318 DOI: 10.1016/j.yexmp.2017.01.003] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2017] [Accepted: 01/04/2017] [Indexed: 02/06/2023]
Abstract
This paper is based upon the "8th Charles Lieber's Satellite Symposium" organized by Manuela G. Neuman at the Research Society on Alcoholism Annual Meeting, on June 25, 2016 at New Orleans, Louisiana, USA. The integrative symposium investigated different aspects of alcohol-induced liver disease (ALD) as well as non-alcohol-induced liver disease (NAFLD) and possible repair. We revealed the basic aspects of alcohol metabolism that may be responsible for the development of liver disease as well as the factors that determine the amount, frequency and which type of alcohol misuse leads to liver and gastrointestinal diseases. We aimed to (1) describe the immuno-pathology of ALD, (2) examine the role of genetics in the development of alcoholic hepatitis (ASH) and NAFLD, (3) propose diagnostic markers of ASH and non-alcoholic steatohepatitis (NASH), (4) examine age and ethnic differences as well as analyze the validity of some models, (5) develop common research tools and biomarkers to study alcohol-induced effects, 6) examine the role of alcohol in oral health and colon and gastrointestinal cancer and (7) focus on factors that aggravate the severity of organ-damage. The present review includes pre-clinical, translational and clinical research that characterizes ALD and NAFLD. Strong clinical and experimental evidence lead to recognition of the key toxic role of alcohol in the pathogenesis of ALD with simple fatty infiltrations and chronic alcoholic hepatitis with hepatic fibrosis or cirrhosis. These latter stages may also be associated with a number of cellular and histological changes, including the presence of Mallory's hyaline, megamitochondria, or perivenular and perisinusoidal fibrosis. Genetic polymorphisms of ethanol metabolizing enzymes and cytochrome p450 (CYP) 2E1 activation may change the severity of ASH and NASH. Other risk factors such as its co-morbidities with chronic viral hepatitis in the presence or absence of human deficiency virus were discussed. Dysregulation of metabolism, as a result of ethanol exposure, in the intestine leads to colon carcinogenesis. The hepatotoxic effects of ethanol undermine the contribution of malnutrition to the liver injury. Dietary interventions such as micro and macronutrients, as well as changes to the microbiota have been suggested. The clinical aspects of NASH, as part of the metabolic syndrome in the aging population, have been presented. The symposium addressed mechanisms and biomarkers of alcohol induced damage to different organs, as well as the role of the microbiome in this dialog. The microbiota regulates and acts as a key element in harmonizing immune responses at intestinal mucosal surfaces. It is known that microbiota is an inducer of proinflammatory T helper 17 cells and regulatory T cells in the intestine. The signals at the sites of inflammation mediate recruitment and differentiation in order to remove inflammatory inducers and promote tissue homeostasis restoration. The change in the intestinal microbiota also influences the change in obesity and regresses the liver steatosis. Evidence on the positive role of moderate alcohol consumption on heart and metabolic diseases as well on reducing steatosis have been looked up. Moreover nutrition as a therapeutic intervention in alcoholic liver disease has been discussed. In addition to the original data, we searched the literature (2008-2016) for the latest publication on the described subjects. In order to obtain the updated data we used the usual engines (Pub Med and Google Scholar). The intention of the eighth symposia was to advance the international profile of the biological research on alcoholism. We also wish to further our mission of leading the forum to progress the science and practice of translational research in alcoholism.
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Affiliation(s)
- Manuela G Neuman
- In Vitro Drug Safety and Biotechnology, Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada; Department of Pharmacology and Toxicology, Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada.
| | | | | | - Stephen Malnick
- Department Internal Medicine, Kaplan Medical Centre and Hebrew University of Jerusalem, Rehovot, Israel
| | - Helmut K Seitz
- Centre of Alcohol Research, University of Heidelberg, Heidelberg, Germany
| | - Lawrence B Cohen
- Division of Gastroenterology, Sunnybrook Health Sciences Centre, Department of Medicine, Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada
| | - Mikko Salaspuro
- Research Unit on Acetaldehyde and Cancer, University of Helsinki, Helsinki, Finland
| | - Andreea Voinea-Griffin
- Public Health Science Texas A&M University, College of Dentistry, Dallas University, TX, USA
| | - Andrei Barasch
- Joan and Sanford I. Weill Department of Medicine, Weill Cornell Medical College, New York, NY, USA
| | - Irina A Kirpich
- Division of Gastroenterology, Hepatology, and Nutrition, Department of Medicine, University of Louisville School of Medicine, Louisville, KY, USA; Department of Pharmacology and Toxicology, University of Louisville School of Medicine, Louisville, KY, USA
| | - Paul G Thomes
- Department of Internal Medicine, Carolinas Medical Center, Charlotte, NC, USA; Department of Internal Medicine, University of Nebraska Medical Center, Omaha, NE, USA
| | - Laura W Schrum
- Department of Internal Medicine, Carolinas Medical Center, Charlotte, NC, USA
| | - Terrence M Donohue
- Department of Internal Medicine, University of Nebraska Medical Center, Omaha, NE, USA
| | - Kusum K Kharbanda
- Department of Internal Medicine, University of Nebraska Medical Center, Omaha, NE, USA; Research Service, Veterans Affairs Nebraska-Western Iowa Health Care System, University of Nebraska Medical Center, Omaha, NE, USA; Department of Biochemistry & Molecular Biology, University of Nebraska Medical Center, Omaha, NE, USA
| | - Marcus Cruz
- In Vitro Drug Safety and Biotechnology, Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada; Department of Pharmacology and Toxicology, Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada
| | - Mihai Opris
- Department of Pharmacology and Toxicology, Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada; Family Medicine Clinic CAR, Bucharest, Romania
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Piano MR. Alcohol's Effects on the Cardiovascular System. Alcohol Res 2017; 38:219-241. [PMID: 28988575 PMCID: PMC5513687] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Alcohol use has complex effects on cardiovascular (CV) health. The associations between drinking and CV diseases such as hypertension, coronary heart disease, stroke, peripheral arterial disease, and cardiomyopathy have been studied extensively and are outlined in this review. Although many behavioral, genetic, and biologic variants influence the interconnection between alcohol use and CV disease, dose and pattern of alcohol consumption seem to modulate this most. Low-to-moderate alcohol use may mitigate certain mechanisms such as risk and hemostatic factors affecting atherosclerosis and inflammation, pathophysiologic processes integral to most CV disease. But any positive aspects of drinking must be weighed against serious physiological effects, including mitochondrial dysfunction and changes in circulation, inflammatory response, oxidative stress, and programmed cell death, as well as anatomical damage to the CV system, especially the heart itself. Both the negative and positive effects of alcohol use on particular CV conditions are presented here. The review concludes by suggesting several promising avenues for future research related to alcohol use and CV disease. These include using direct biomarkers of alcohol to confirm self-report of alcohol consumption levels; studying potential mediation of various genetic, socioeconomic, and racial and ethnic factors that may affect alcohol use and CV disease; reviewing alcohol-medication interactions in cardiac patients; and examining CV effects of alcohol use in young adults and in older adults.
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Guan ZF, Zhou XL, Zhang XM, Zhang Y, Wang YM, Guo QL, Ji G, Wu GF, Wang NN, Yang H, Yu ZY, Zhou HG, Guo JC, Liu YC. Beclin-1- mediated autophagy may be involved in the elderly cognitive and affective disorders in streptozotocin-induced diabetic mice. Transl Neurodegener 2016; 5:22. [PMID: 27999666 PMCID: PMC5154026 DOI: 10.1186/s40035-016-0070-4] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2016] [Accepted: 12/04/2016] [Indexed: 02/07/2023] Open
Abstract
Background Diabetes is the most common metabolic disease with many chronic complications, and cognitive disorders are one of the common complications in patients with diabetes. Previous studies have showed that autophagy played important roles in the progression of metabolic syndrome, diabetes and other diseases. So we investigated whether aged diabetic mice are prone to be associated with the cognitive and affective disorders and whether Beclin-1-mediated autophagy might be involved in thepahological process. Methods High-fat diet/streptozotocin (STZ) injection-induced diabetic C57 mice were adopted in this study. Cognitive disorders were detected by Morris water maze and fear conditional test. Affective disorders were detected by tail suspension test and forced swimming test. Magnetic resonance imaging was applied to observe changes of morphology and metabolism in the brain. The 18 F-fluorodeoxyglucose positron emission tomography (FDG-PET) was used to assess metabolism changes in the brain of aged diabetic mice. Autophagy were evaluated by Beclin- 1, LC3II/I and P62, which were detected by western blot analysis and observed by electron microscopy. Results 1. Compared with control group, diabetes mice showed significantly decreasing abilities in spatial memory and conditioned fear memory (all P < 0.05), and increasing tendency of depression (P < 0.05). 2. MRI showed that the majority of elderly diabetic mice were associated with multiple cerebral small vessel disease. Some even showed hippocampal atrophy, ventricular dilatation and leukoaraiosis. 3. FDG-PET-CT discovered that the glucose metabolism in the amygdala and hippocampus was significantly decreased compared with normal aged mice (P < 0.05). 4. Electron microscopy found that, although autophagy bodies was not widespread, and there was no significant difference between the two groups, yet compared with normal aged mice, apparent cell edema, myelinated tow reduction and intracellular lipofuscin augmentation existed in elderly diabetic mice brain. 5. The level of p62 was increased in the STZ-induced diabetic mice hippocampus and striatum, and beclin1 protein expression were significantly decreased in diabetic mice hippocampus compared with normal aged mice (P < 0.05). There was a upward trend of the ratio of LC3II/I in hippocampus, cortex and striatum, but no statistically difference between the two groups. Conclusion Compared with normal aged mice, diabetic aged mice were apt to cerebral small vessel disease and associated with cognitive and affective disorders, which may be related to the significantly reduced glucose metabolism in hippocampus and amygdala. Beclin1 mediated autophagy in hippocampus probably played an important role in cognitive and affective disorders of STZ-induced aged diabetic mice.
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Affiliation(s)
- Zhu-Fei Guan
- Department of Geriatric Neurology, Huashan Hospital, Fudan University; National Clinical Medicine Research Center for Age-related Diseases, 12 Middle WuLuMuQi Rd, Shanghai, 200040 China ; State Key Laboratory of Medical Neurobiology, Department of Neurobiology, School of Basic Medical Neurobiology, Department of Neurobiology School of Basic Medical Science, Shanghai Medical College, Fudan University, 131 DongAn Rd, Shanghai, 200032 China
| | - Xiu-Ling Zhou
- Department of Ultrasonics, Huashan Hospital, Fudan University, Shanghai, 200040 China
| | - Xiao-Ming Zhang
- Department of Geriatric Neurology, Huashan Hospital, Fudan University; National Clinical Medicine Research Center for Age-related Diseases, 12 Middle WuLuMuQi Rd, Shanghai, 200040 China
| | - Yu Zhang
- Department of Geriatric Neurology, Huashan Hospital, Fudan University; National Clinical Medicine Research Center for Age-related Diseases, 12 Middle WuLuMuQi Rd, Shanghai, 200040 China
| | - Yan-Mei Wang
- Department of Geriatric Neurology, Huashan Hospital, Fudan University; National Clinical Medicine Research Center for Age-related Diseases, 12 Middle WuLuMuQi Rd, Shanghai, 200040 China
| | - Qi-Lin Guo
- State Key Laboratory of Medical Neurobiology, Department of Neurobiology, School of Basic Medical Neurobiology, Department of Neurobiology School of Basic Medical Science, Shanghai Medical College, Fudan University, 131 DongAn Rd, Shanghai, 200032 China
| | - Gang Ji
- State Key Laboratory of Medical Neurobiology, Department of Neurobiology, School of Basic Medical Neurobiology, Department of Neurobiology School of Basic Medical Science, Shanghai Medical College, Fudan University, 131 DongAn Rd, Shanghai, 200032 China
| | - Guo-Feng Wu
- Department of EmergencyNeurology, Guiyang Medical University, Guiyang, 550004 China
| | - Na-Na Wang
- Department of Geriatric Neurology, Huashan Hospital, Fudan University; National Clinical Medicine Research Center for Age-related Diseases, 12 Middle WuLuMuQi Rd, Shanghai, 200040 China
| | - Hao Yang
- Department of Geriatric Neurology, Huashan Hospital, Fudan University; National Clinical Medicine Research Center for Age-related Diseases, 12 Middle WuLuMuQi Rd, Shanghai, 200040 China
| | - Zhong-Yu Yu
- Department of Geriatric Neurology, Huashan Hospital, Fudan University; National Clinical Medicine Research Center for Age-related Diseases, 12 Middle WuLuMuQi Rd, Shanghai, 200040 China
| | - Hou-Guang Zhou
- Department of Geriatric Neurology, Huashan Hospital, Fudan University; National Clinical Medicine Research Center for Age-related Diseases, 12 Middle WuLuMuQi Rd, Shanghai, 200040 China
| | - Jing-Chun Guo
- State Key Laboratory of Medical Neurobiology, Department of Neurobiology, School of Basic Medical Neurobiology, Department of Neurobiology School of Basic Medical Science, Shanghai Medical College, Fudan University, 131 DongAn Rd, Shanghai, 200032 China
| | - Ying-Chao Liu
- Department of Neurosurgery, Shandong Provincial Hospital, 5 Latitude and 7 longitude Rd, Jinan, 250021 China
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Role of Autophagy in HIV Pathogenesis and Drug Abuse. Mol Neurobiol 2016; 54:5855-5867. [PMID: 27660273 DOI: 10.1007/s12035-016-0118-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2016] [Accepted: 09/12/2016] [Indexed: 12/27/2022]
Abstract
Autophagy is a highly regulated process in which excessive cytoplasmic materials are captured and degraded during deprivation conditions. The unique nature of autophagy that clears invasive microorganisms has made it an important cellular defense mechanism in a variety of clinical situations. In recent years, it has become increasingly clear that autophagy is extensively involved in the pathology of HIV-1. To ensure survival of the virus, HIV-1 viral proteins modulate and utilize the autophagy pathway so that biosynthesis of the virus is maximized. At the same time, the abuse of illicit drugs such as methamphetamine, cocaine, morphine, and alcohol is thought to be a significant risk factor for the acquirement and progression of HIV-1. During drug-induced toxicity, autophagic activity has been proved to be altered in various cell types. Here, we review the current literature on the interaction between autophagy, HIV-1, and drug abuse and discuss the complex role of autophagy during HIV-1 pathogenesis in co-exposure to illicit drugs.
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Molecular mechanism of hepatic steatosis: pathophysiological role of autophagy. Expert Rev Mol Med 2016; 18:e14. [PMID: 27499351 DOI: 10.1017/erm.2016.14] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
UNLABELLED Steatosis is an early characteristic in the pathogenesis of fatty liver disease (FLD). Mechanisms of hepatic steatosis are aetiology-dependent. Activation of autophagy in liver ameliorates hepatic steatosis. A modulation of hepatic autophagy affects the degree of hepatocyte steatosis and the progression of FLD as demonstrated by pre-clinical models and clinical trials. This review summarises recent advances on pathophysiological roles of autophagy in hepatic lipid metabolism. A comprehensive regulation of autophagic networks holds promise for the improvement of hepatic steatosis. Autophagic signalling pathway may be a novel therapeutic target against FLD. HIGHLIGHTS • Hepatic steatosis is a pathological condition wherein vacuoles of triglyceride (TG) fat are overaccumulated in liver because of abnormal metabolism of lipids. • Hepatic autophagy regulates lipid metabolism as demonstrated by macrolipophagy in response to starvation and hepatic overabundance of TG in obesity. • Autophagic signals are closely associated with apoptotic pathways. There is distinctive relationship between hepatic autophagy and apoptosis, which affects the progression of fatty liver. • Regulation of autophagic process can be a novel therapeutic strategy for fatty liver disease.
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Abstract
Ethanol metabolism in hepatocytes causes the generation of reactive oxygen species, endoplasmic reticulum stress and alterations in mitochondrial energy and REDOX metabolism. In ethanol-exposed liver disease, autophagy not only acts as a cleanser to remove damaged organelles and cytosolic components, but also selectively clears specific targets such as lipid droplets and damaged mitochondria. Moreover, ethanol appears to play a role in protecting hepatocytes from apoptosis at certain concentrations. This article describes the evidence, function and potential mechanism of autophagy in ethanol-exposed liver disease and the controversy surrounding the effects of ethanol on autophagy.
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Affiliation(s)
- Li-Ren Wang
- Department of Infection and Liver Diseases, Liver Research Center, the First Affiliated Hospital of Wenzhou Medical University, Wenzhou 325000, China
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Pla A, Pascual M, Guerri C. Autophagy Constitutes a Protective Mechanism against Ethanol Toxicity in Mouse Astrocytes and Neurons. PLoS One 2016; 11:e0153097. [PMID: 27070930 PMCID: PMC4829237 DOI: 10.1371/journal.pone.0153097] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2016] [Accepted: 03/23/2016] [Indexed: 11/19/2022] Open
Abstract
Ethanol induces brain damage and neurodegeneration by triggering inflammatory processes in glial cells through activation of Toll-like receptor 4 (TLR4) signaling. Recent evidence indicates the role of protein degradation pathways in neurodegeneration and alcoholic liver disease, but how these processes affect the brain remains elusive. We have demonstrated that chronic ethanol consumption impairs proteolytic pathways in mouse brain, and the immune response mediated by TLR4 receptors participates in these dysfunctions. We evaluate the in vitro effects of an acute ethanol dose on the autophagy-lysosome pathway (ALP) on WT and TLR4-/- mouse astrocytes and neurons in primary culture, and how these changes affect cell survival. Our results show that ethanol induces overexpression of several autophagy markers (ATG12, LC3-II, CTSB), and increases the number of lysosomes in WT astrocytes, effects accompanied by a basification of lysosomal pH and by lowered phosphorylation levels of autophagy inhibitor mTOR, along with activation of complexes beclin-1 and ULK1. Notably, we found only minor changes between control and ethanol-treated TLR4-/- mouse astroglial cells. Ethanol also triggers the expression of the inflammatory mediators iNOS and COX-2, but induces astroglial death only slightly. Blocking autophagy by using specific inhibitors increases both inflammation and cell death. Conversely, in neurons, ethanol down-regulates the autophagy pathway and triggers cell death, which is partially recovered by using autophagy enhancers. These results support the protective role of the ALP against ethanol-induced astroglial cell damage in a TLR4-dependent manner, and provide new insight into the mechanisms that underlie ethanol-induced brain damage and are neuronal sensitive to the ethanol effects.
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Affiliation(s)
- Antoni Pla
- Department of Cellular Pathology, Centro de Investigación Príncipe Felipe, C/ Eduardo Primo Yúfera 3, 46012, Valencia, Spain
| | - María Pascual
- Department of Cellular Pathology, Centro de Investigación Príncipe Felipe, C/ Eduardo Primo Yúfera 3, 46012, Valencia, Spain
| | - Consuelo Guerri
- Department of Cellular Pathology, Centro de Investigación Príncipe Felipe, C/ Eduardo Primo Yúfera 3, 46012, Valencia, Spain
- * E-mail:
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Abstract
Alcoholic liver disease (ALD) is a leading cause of liver-related morbidity and mortality worldwide. ALD encompasses a spectrum of disorders including asymptomatic steatosis, steatohepatitis, fibrosis, cirrhosis and its related complications, and the acute-on-chronic state of alcoholic hepatitis. While multidisciplinary efforts continue to be aimed at curbing progression of this spectrum of disorders, there is an urgent need to focus our efforts on effective therapeutic interventions for alcoholic hepatitis (AH), the most severe form of ALD. AH is characterized by an abrupt development of jaundice and complications related to liver insufficiency and portal hypertension in patients with heavy alcohol intake. The mortality of patients with severe AH is very high (20-50 % at 3 months). The current therapeutic regimens are limited. The development of new therapies requires translational studies in human samples and suitable animal models that reproduce clinical and histological features of human AH. This review article summarizes the clinical syndrome, pre-clinical translational tools, and pathogenesis of AH at a molecular and cellular level, with the aim of identifying new targets of potential therapeutic intervention.
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Lívero FA, Acco A. Molecular basis of alcoholic fatty liver disease: From incidence to treatment. Hepatol Res 2016; 46:111-23. [PMID: 26417962 DOI: 10.1111/hepr.12594] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/28/2015] [Revised: 09/14/2015] [Accepted: 09/16/2015] [Indexed: 12/11/2022]
Abstract
Alcoholic liver diseases have complex and multiple pathogenic mechanisms but still no effective treatment. Steatosis or alcoholic fatty liver disease (AFLD) has a widespread incidence and is the first step in the progression to more severe stages of alcoholic liver disease, with concomitant increases in morbidity and mortality rates. The ways in which this progression occurs and why some individuals are susceptible are still unanswered scientific questions. Research with animal models and clinical evidence have shown that it is a multifactorial disease that involves interactions between lipid metabolism, inflammation, the immune response and oxidative stress. Each of these pathways provides a better understanding of the pathogenesis of AFLD and contributes to the development of therapeutic strategies. This review emphasizes the importance of research on alcoholic steatosis based on incidence data, key pathogenic mechanisms and therapeutic interventions, and discusses perspectives on the progression of this disease.
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Affiliation(s)
| | - Alexandra Acco
- Department of Pharmacology, Federal University of Paraná, Curitiba, Brazil
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Autophagy Protects against CYP2E1/Chronic Ethanol-Induced Hepatotoxicity. Biomolecules 2015; 5:2659-74. [PMID: 26501338 PMCID: PMC4693252 DOI: 10.3390/biom5042659] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2015] [Revised: 10/09/2015] [Accepted: 10/09/2015] [Indexed: 02/07/2023] Open
Abstract
Autophagy is an intracellular pathway by which lysosomes degrade and recycle long-lived proteins and cellular organelles. The effects of ethanol on autophagy are complex but recent studies have shown that autophagy serves a protective function against ethanol-induced liver injury. Autophagy was found to also be protective against CYP2E1-dependent toxicity in vitro in HepG2 cells which express CYP2E1 and in vivo in an acute alcohol/CYPE1-dependent liver injury model. The goal of the current report was to extend the previous in vitro and acute in vivo experiments to a chronic ethanol model to evaluate whether autophagy is also protective against CYP2E1-dependent liver injury in a chronic ethanol-fed mouse model. Wild type (WT), CYP2E1 knockout (KO) or CYP2E1 humanized transgenic knockin (KI), mice were fed an ethanol liquid diet or control dextrose diet for four weeks. In the last week, some mice received either saline or 3-methyladenine (3-MA), an inhibitor of autophagy, or rapamycin, which stimulates autophagy. Inhibition of autophagy by 3-MA potentiated the ethanol-induced increases in serum transaminase and triglyceride levels in the WT and KI mice but not KO mice, while rapamycin prevented the ethanol liver injury. Treatment with 3-MA enhanced the ethanol-induced fat accumulation in WT mice and caused necrosis in the KI mice; little or no effect was found in the ethanol-fed KO mice or any of the dextrose-fed mice. 3-MA treatment further lowered the ethanol-decrease in hepatic GSH levels and further increased formation of TBARS in WT and KI mice, whereas rapamycin blunted these effects of ethanol. Neither 3-MA nor rapamycin treatment affected CYP2E1 catalytic activity or content or the induction CYP2E1 by ethanol. The 3-MA treatment decreased levels of Beclin-1 and Atg 7 but increased levels of p62 in the ethanol-fed WT and KI mice whereas rapamycin had the opposite effects, validating inhibition and stimulation of autophagy, respectively. These results suggest that autophagy is protective against CYP2E1-dependent liver injury in a chronic ethanol-fed mouse model. We speculate that autophagy-dependent processes such as mitophagy and lipophagy help to minimize ethanol-induced CYP2E1-dependent oxidative stress and therefore the subsequent liver injury and steatosis. Attempts to stimulate autophagy may be helpful in lowering ethanol and CYP2E1-dependent liver toxicity.
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Ji C. Advances and New Concepts in Alcohol-Induced Organelle Stress, Unfolded Protein Responses and Organ Damage. Biomolecules 2015; 5:1099-121. [PMID: 26047032 PMCID: PMC4496712 DOI: 10.3390/biom5021099] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2015] [Revised: 05/23/2015] [Accepted: 05/26/2015] [Indexed: 12/20/2022] Open
Abstract
Alcohol is a simple and consumable biomolecule yet its excessive consumption disturbs numerous biological pathways damaging nearly all organs of the human body. One of the essential biological processes affected by the harmful effects of alcohol is proteostasis, which regulates the balance between biogenesis and turnover of proteins within and outside the cell. A significant amount of published evidence indicates that alcohol and its metabolites directly or indirectly interfere with protein homeostasis in the endoplasmic reticulum (ER) causing an accumulation of unfolded or misfolded proteins, which triggers the unfolded protein response (UPR) leading to either restoration of homeostasis or cell death, inflammation and other pathologies under severe and chronic alcohol conditions. The UPR senses the abnormal protein accumulation and activates transcription factors that regulate nuclear transcription of genes related to ER function. Similarly, this kind of protein stress response can occur in other cellular organelles, which is an evolving field of interest. Here, I review recent advances in the alcohol-induced ER stress response as well as discuss new concepts on alcohol-induced mitochondrial, Golgi and lysosomal stress responses and injuries.
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Affiliation(s)
- Cheng Ji
- GI/Liver Division, Research Center for Liver Disease, Department of Medicine, Keck School of Medicine of USC, University of Southern California, Los Angeles, CA 90033, USA.
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On the mechanism underlying ethanol-induced mitochondrial dynamic disruption and autophagy response. Biochim Biophys Acta Mol Basis Dis 2015; 1852:1400-9. [PMID: 25779081 DOI: 10.1016/j.bbadis.2015.03.006] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2014] [Revised: 02/20/2015] [Accepted: 03/07/2015] [Indexed: 12/15/2022]
Abstract
We have explored the mechanisms underlying ethanol-induced mitochondrial dynamics disruption and mitophagy. Ethanol increases mitochondrial fission in a concentration-dependent manner through Drp1 mitochondrial translocation and OPA1 proteolytic cleavage. ARPE-19 (a human retinal pigment epithelial cell line) cells challenged with ethanol showed mitochondrial potential disruptions mediated by alterations in mitochondrial complex IV protein level and increases in mitochondrial reactive oxygen species production. In addition, ethanol activated the canonical autophagic pathway, as denoted by autophagosome formation and autophagy regulator elements including Beclin1, ATG5-ATG12 and P-S6 kinase. Likewise, autophagy inhibition dramatically increased mitochondrial fission and cell death, whereas autophagy stimulation rendered the opposite results, placing autophagy as a cytoprotective response aimed to remove damaged mitochondria. Interestingly, although ethanol induced mitochondrial Bax translocation, this episode was associated to cell death rather than mitochondrial fission or autophagy responses. Thus, Bax required 600 mM ethanol to migrate to mitochondria, a concentration that resulted in cell death. Furthermore, mouse embryonic fibroblasts lacking this protein respond to ethanol by undergoing mitochondrial fission and autophagy but not cytotoxicity. Finally, by using the specific mitochondrial-targeted scavenger MitoQ, we revealed mitochondria as the main source of reactive oxygen species that trigger autophagy activation. These findings suggest that cells respond to ethanol activating mitochondrial fission machinery by Drp1 and OPA1 rather than bax, in a manner that stimulates cytoprotective autophagy through mitochondrial ROS.
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Guo R, Xu X, Babcock SA, Zhang Y, Ren J. Aldehyde dedydrogenase-2 plays a beneficial role in ameliorating chronic alcohol-induced hepatic steatosis and inflammation through regulation of autophagy. J Hepatol 2015; 62:647-56. [PMID: 25457208 PMCID: PMC4336638 DOI: 10.1016/j.jhep.2014.10.009] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/05/2013] [Revised: 09/08/2014] [Accepted: 10/08/2014] [Indexed: 12/15/2022]
Abstract
BACKGROUND & AIMS Mitochondrial aldehyde dehydrogenase (ALDH2) plays a critical role in the detoxification of the ethanol metabolite acetaldehyde. This study was designed to examine the impact of global ALDH2 overexpression on alcohol-induced hepatic steatosis. METHODS Wild type Friend virus B (FVB) and ALDH2 transgenic mice were placed on a 4% alcohol or control diet for 12 weeks. Serum levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), bilirubin and cholesterol, hepatic triglyceride, steatosis, fat metabolism-related proteins, pro-inflammatory cytokines, glutathione (GSH), oxidized glutathione (GSSG), autophagy and autophagy signalling were examined. The role of autophagy was evaluated in alcohol dehydrogenase 1 (ADH1)-transfected human hepatocellular liver carcinoma cells (VA-13) treated with or without the autophagy inducer rapamycin and lysosomal inhibitors. RESULTS Chronic alcohol intake led to elevated AST-, ALT-levels, bilirubin, AST/ALT ratio, cholesterol, hepatic triglycerides and hepatic fat deposition as evidenced by H&E and Oil Red O staining. Hepatic fat deposition was associated with disturbed levels of fat metabolism-related proteins (fatty acid synthase, SCD1), upregulated interleukin-6, TNF-α, cyclooxygenase, oxidative stress, and loss of autophagy, effects which were attenuated or ablated by the ALDH2 transgene. Moreover, ethanol (100 mM) and acetaldehyde (100 and 500 μM) increased levels of IL-6 and IFN-γ, and suppressed autophagy in VA-13 cells, effects which were markedly alleviated by rapamycin. In addition, lysosomal inhibitors mimicked ethanol-induced p62 accumulation with little additive effect with ethanol. Ethanol significantly suppressed LC3 conversion in the presence of lysosomal inhibitors. CONCLUSIONS In summary, our results revealed that ALDH2 plays a beneficial role in ameliorating chronic alcohol intake-induced hepatic steatosis and inflammation through regulation of autophagy.
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Affiliation(s)
- Rui Guo
- Center for Cardiovascular Research and Alternative Medicine, University of Wyoming College of Health Sciences, Laramie, USA
| | - Xihui Xu
- Center for Cardiovascular Research and Alternative Medicine, University of Wyoming College of Health Sciences, Laramie, USA
| | - Sara A Babcock
- Center for Cardiovascular Research and Alternative Medicine, University of Wyoming College of Health Sciences, Laramie, USA
| | - Yingmei Zhang
- Center for Cardiovascular Research and Alternative Medicine, University of Wyoming College of Health Sciences, Laramie, USA; Department of Cardiology, Xijing Hospital, Fourth Military Medical University, Xi'an, China; Department of Cardiology, Zhongshan Hospital, Fudan University, Shanghai, China.
| | - Jun Ren
- Center for Cardiovascular Research and Alternative Medicine, University of Wyoming College of Health Sciences, Laramie, USA; Department of Cardiology, Zhongshan Hospital, Fudan University, Shanghai, China.
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Ceni E, Mello T, Galli A. Pathogenesis of alcoholic liver disease: Role of oxidative metabolism. World J Gastroenterol 2014; 20:17756-17772. [PMID: 25548474 PMCID: PMC4273126 DOI: 10.3748/wjg.v20.i47.17756] [Citation(s) in RCA: 314] [Impact Index Per Article: 31.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/11/2014] [Revised: 05/22/2014] [Accepted: 08/28/2014] [Indexed: 02/06/2023] Open
Abstract
Alcohol consumption is a predominant etiological factor in the pathogenesis of chronic liver diseases, resulting in fatty liver, alcoholic hepatitis, fibrosis/cirrhosis, and hepatocellular carcinoma (HCC). Although the pathogenesis of alcoholic liver disease (ALD) involves complex and still unclear biological processes, the oxidative metabolites of ethanol such as acetaldehyde and reactive oxygen species (ROS) play a preeminent role in the clinical and pathological spectrum of ALD. Ethanol oxidative metabolism influences intracellular signaling pathways and deranges the transcriptional control of several genes, leading to fat accumulation, fibrogenesis and activation of innate and adaptive immunity. Acetaldehyde is known to be toxic to the liver and alters lipid homeostasis, decreasing peroxisome proliferator-activated receptors and increasing sterol regulatory element binding protein activity via an AMP-activated protein kinase (AMPK)-dependent mechanism. AMPK activation by ROS modulates autophagy, which has an important role in removing lipid droplets. Acetaldehyde and aldehydes generated from lipid peroxidation induce collagen synthesis by their ability to form protein adducts that activate transforming-growth-factor-β-dependent and independent profibrogenic pathways in activated hepatic stellate cells (HSCs). Furthermore, activation of innate and adaptive immunity in response to ethanol metabolism plays a key role in the development and progression of ALD. Acetaldehyde alters the intestinal barrier and promote lipopolysaccharide (LPS) translocation by disrupting tight and adherent junctions in human colonic mucosa. Acetaldehyde and LPS induce Kupffer cells to release ROS and proinflammatory cytokines and chemokines that contribute to neutrophils infiltration. In addition, alcohol consumption inhibits natural killer cells that are cytotoxic to HSCs and thus have an important antifibrotic function in the liver. Ethanol metabolism may also interfere with cell-mediated adaptive immunity by impairing proteasome function in macrophages and dendritic cells, and consequently alters allogenic antigen presentation. Finally, acetaldehyde and ROS have a role in alcohol-related carcinogenesis because they can form DNA adducts that are prone to mutagenesis, and they interfere with methylation, synthesis and repair of DNA, thereby increasing HCC susceptibility.
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Effect of Golgi phosphoprotein 2 (GOLPH2/GP73) on autophagy in human hepatocellular carcinoma HepG2 cells. Tumour Biol 2014; 36:3399-406. [PMID: 25527157 DOI: 10.1007/s13277-014-2974-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2014] [Accepted: 12/10/2014] [Indexed: 12/29/2022] Open
Abstract
This study aims to investigate the effect of Golgi Protein 73 (GP73) on autophagy in human hepatoma line cells HepG2. We investigated the functional effects of GP73 on autophagy in hepatoma cell line HepG2 using immunofluoscence staining, Western blotting and real-time PCR. Our data showed that specific small interference RNA (siRNA) notably induced formation of autophagic vacuoles. In addition, upregulation of GP73 significantly inhibited formation of starvation-induced LC3-positive structures. We provide the first experimental evidence to show that GP73 may play an important role in the inhibitory regulation of autophagy. Therefore, our data suggest a new molecular mechanism for GP73-related hepatoma progression.
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Abstract
Alcoholic cardiomyopathy (ACM) is a specific heart muscle disease found in individuals with a history of long-term heavy alcohol consumption. ACM is associated with a number of adverse histological, cellular, and structural changes within the myocardium. Several mechanisms are implicated in mediating the adverse effects of ethanol, including the generation of oxidative stress, apoptotic cell death, impaired mitochondrial bioenergetics/stress, derangements in fatty acid metabolism and transport, and accelerated protein catabolism. In this review, we discuss the evidence for such mechanisms and present the potential importance of drinking patterns, genetic susceptibility, nutritional factors, race, and sex. The purpose of this review is to provide a mechanistic paradigm for future research in the area of ACM.
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Affiliation(s)
- Mariann R. Piano
- Professor and Department Head, Department of Biobehavioral Health Science (MC 807), University of Illinois at Chicago, 845 S. Damen Ave., Chicago, IL 60612, 312-413-0132 (TEL), 312-996-4979,
| | - Shane A. Phillips
- Associate Professor and Associate Department Head, Department of Physical Therapy, University of Illinois at Chicago, 1919 W. Taylor St. (MC 898), Chicago, IL 60612, 312-355-0277 (TEL),
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Pretreatment with wortmannin alleviates lipopolysaccharide/d-galactosamine-induced acute liver injury. Biochem Biophys Res Commun 2014; 455:234-40. [DOI: 10.1016/j.bbrc.2014.10.152] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2014] [Accepted: 10/30/2014] [Indexed: 02/07/2023]
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Abstract
The pathogenic mechanism underlying alcoholic fatty liver (AFL) is not clear. Autophagy is a self-digestion process that is critical for the maintenance of cellular homeostasis and regulation of lipid metabolism. We investigated the role of autophagy and autophagic flux in hepatic injury induced by chronic ethanol feeding in mice. C57BL/6 mice were fed a Lieber-DeCarli ethanol diet (ED) to induce AFL or an isocaloric control diet for 6 weeks. Chloroquine (CQ, 10 mg/kg, intra-peritoneally [i.p.]) or rapamycin (Rapa, 5 mg/kg, i.p.) were administered during the last 2 weeks of the experimental period. Chronic ethanol feeding induced AFL with focal necrosis associated with increased levels of hepatic triglyceride. This phenomenon was aggravated by CQ, an inhibitor of autophagy, and attenuated by Rapa, an inducer of autophagy. Expression of microtubule-associated protein 1 light chain 3 (LC3)-II and sequestosome1/p62 significantly increased in the ED group. Moreover, accumulation of autophagosomes was observed by transmission electron microscopy in chronic ethanol-treated mice. Chronic ethanol consumption decreased protein expression of LC3 lipidation-related proteins Atg3 and Atg7, and the lysosomal proteins lysosome-associated membrane protein-2 and Rab7, and increased the protein expression of calpain 1 and phosphorylated mammalian target of rapamycin. Taken together, these findings suggest that chronic ethanol consumption leads to impairment of autophagic flux, which contributes to ethanol-induced liver injury.
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Donohue TM, Thomes PG. Ethanol-induced oxidant stress modulates hepatic autophagy and proteasome activity. Redox Biol 2014; 3:29-39. [PMID: 25462063 PMCID: PMC4297932 DOI: 10.1016/j.redox.2014.10.006] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2014] [Revised: 10/27/2014] [Accepted: 10/28/2014] [Indexed: 02/07/2023] Open
Abstract
In this review, we describe research findings on the effects of alcohol exposure on two major catabolic systems in liver cells: the ubiquitin-proteasome system (UPS) and autophagy. These hydrolytic systems are not unique to liver cells; they exist in all eukaryotic tissues and cells. However, because the liver is the principal site of ethanol metabolism, it sustains the greatest damage from heavy drinking. Thus, the focus of this review is to specifically describe how ethanol oxidation modulates the activities of the UPS and autophagy and the mechanisms by which these changes contribute to the pathogenesis of alcohol-induced liver injury. Here, we describe the history and the importance of cellular hydrolytic systems, followed by a description of each catabolic pathway and the differential modulation of each by ethanol exposure. Overall, the evidence for an involvement of these catabolic systems in the pathogenesis of alcoholic liver disease is quite strong. It underscores their importance, not only as effective means of cellular recycling and eventual energy generation, but also as essential components of cellular defense.
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Affiliation(s)
- Terrence M Donohue
- Research Service (151), VA-Nebraska-Western Iowa Health Care System, Omaha, NE 68105, USA; Department of Internal Medicine, College of Medicine, USA; Department of Biochemistry and Molecular Biology, College of Medicine, USA; Department of Pathology and Microbiology, College of Medicine, USA; The Center for Environmental Health and Toxicology, College of Public Health, University of Nebraska Medical Center, Omaha, NE, 68198, USA.
| | - Paul G Thomes
- Research Service (151), VA-Nebraska-Western Iowa Health Care System, Omaha, NE 68105, USA; Department of Internal Medicine, College of Medicine, USA
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Xu J, Liu X, Gao B, Karin M, Tsukamoto H, Brenner D, Kisseleva T. New Approaches for Studying Alcoholic Liver Disease. CURRENT PATHOBIOLOGY REPORTS 2014; 2:171-183. [PMID: 26594598 DOI: 10.1007/s40139-014-0053-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Alcoholic liver disease (ALD) is major cause of chronic liver injury which results in liver fibrosis and cirrhosis. According to the surveillance report published by the National Institute on Alcohol Abuse and Alcoholism, liver cirrhosis is the 12th leading cause of death in the United States with 48 % of these deaths being attributed to excessive alcohol consumption. ALD includes a spectrum of disorders from simple steatosis to steatohepatitis, fibrosis, and hepatocellular carcinoma. Several mechanisms play a critical role in the pathogenesis of ALD. These include ethanol-induced oxidative stress and depletion of glutathione, pathological methionine metabolism, increased gut permeability and release of endotoxins into the portal blood, recruitment and activation of inflammatory cells including bone marrow-derived and liver resident macrophages (Kupffer cells). Chronic alcohol consumption results in liver damage and activation of hepatic stellate cells (HSCs) and myofibroblasts, leading to liver fibrosis. Here we discuss the current view on factors that are specific for different stages of ALD and those that regulate its progression, including cytokines and chemokines, alcohol-responsive intracellular signaling pathways, and transcriptional factors. We also review recent studies demonstrating that alcohol-mediated changes can be regulated on an epigenetic level, including microRNAs. Finally, we discuss the reversibility of liver fibrosis and inactivation of HSCs as a potential strategy for treating alcohol-induced liver damage.
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Affiliation(s)
- Jun Xu
- Department of Medicine, UC San Diego, San Diego, CA, USA
| | - Xiao Liu
- Department of Medicine, UC San Diego, San Diego, CA, USA
| | - Bin Gao
- Laboratory of Liver Diseases, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD, USA
| | - Michael Karin
- Department of Pharmacology, UC San Diego, San Diego, CA, USA
| | - Hidekazu Tsukamoto
- Southern California Research Center for ALPD & Cirrhosis Department of Pathology Keck School of Medicine of USC, University of Southern California, Los Angeles, CA, USA
| | - David Brenner
- Department of Medicine, UC San Diego, San Diego, CA, USA
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Diabetes and the brain: oxidative stress, inflammation, and autophagy. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2014; 2014:102158. [PMID: 25215171 PMCID: PMC4158559 DOI: 10.1155/2014/102158] [Citation(s) in RCA: 292] [Impact Index Per Article: 29.2] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/03/2013] [Revised: 07/30/2014] [Accepted: 07/30/2014] [Indexed: 12/19/2022]
Abstract
Diabetes mellitus is a common metabolic disorder associated with chronic complications including a state of mild to moderate cognitive impairment, in particular psychomotor slowing and reduced mental flexibility, not attributable to other causes, and shares many symptoms that are best described as accelerated brain ageing. A common theory for aging and for the pathogenesis of this cerebral dysfunctioning in diabetes relates cell death to oxidative stress in strong association to inflammation, and in fact nuclear factor κB (NFκB), a master regulator of inflammation and also a sensor of oxidative stress, has a strategic position at the crossroad between oxidative stress and inflammation. Moreover, metabolic inflammation is, in turn, related to the induction of various intracellular stresses such as mitochondrial oxidative stress, endoplasmic reticulum (ER) stress, and autophagy defect. In parallel, blockade of autophagy can relate to proinflammatory signaling via oxidative stress pathway and NFκB-mediated inflammation.
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Autophagy in alcohol-induced multiorgan injury: mechanisms and potential therapeutic targets. BIOMED RESEARCH INTERNATIONAL 2014; 2014:498491. [PMID: 25140315 PMCID: PMC4124834 DOI: 10.1155/2014/498491] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/04/2014] [Accepted: 06/29/2014] [Indexed: 12/21/2022]
Abstract
Autophagy is a genetically programmed, evolutionarily conserved intracellular degradation pathway involved in the trafficking of long-lived proteins and cellular organelles to the lysosome for degradation to maintain cellular homeostasis. Alcohol consumption leads to injury in various tissues and organs including liver, pancreas, heart, brain, and muscle. Emerging evidence suggests that autophagy is involved in alcohol-induced tissue injury. Autophagy serves as a cellular protective mechanism against alcohol-induced tissue injury in most tissues but could be detrimental in heart and muscle. This review summarizes current knowledge about the role of autophagy in alcohol-induced injury in different tissues/organs and its potential molecular mechanisms as well as possible therapeutic targets based on modulation of autophagy.
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Phospholipase D1 decreases type I collagen levels in hepatic stellate cells via induction of autophagy. Biochem Biophys Res Commun 2014; 449:38-43. [PMID: 24802400 DOI: 10.1016/j.bbrc.2014.04.149] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2014] [Accepted: 04/28/2014] [Indexed: 11/24/2022]
Abstract
Hepatic stellate cells (HSCs) are major players in liver fibrogenesis. Accumulating evidence shows that suppression of autophagy plays an important role in the development and progression of liver disease. Phospholipase D1 (PLD1), which catalyzes the hydrolysis of phosphatidylcholine to yield phosphatidic acid (PA) and choline, was recently shown to modulate autophagy. However, little is known about the effects of PLD1 on the production of type I collagen that characterizes liver fibrosis. Here, we examined whether PLD1 regulates type I collagen levels in HSCs through induction of autophagy. Adenovirus-mediated overexpression of PLD-1 (Ad-PLD1) reduced type I collagen levels in the activated human HSC lines, hTERT and LX2. Overexpression of PLD1 in HSCs led to induction of autophagy as demonstrated by increased LC3-II conversion and formation of LC3 puncta, and decreased p62 abundance. Moreover, inhibiting the induction of autophagy by treating cells with bafilomycin or a small interfering (si)RNA for ATG7 rescued Ad-PLD1-induced suppression of type I collagen accumulation in HSCs. The effects of PLD on type I collagen levels were not related to TGF-β/Smad signaling. Furthermore, treatment of cells with PA induced autophagy and inhibited type I collagen accumulation. The present study indicates that PLD1 plays a role in regulating type I collagen accumulation through induction of autophagy.
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Pi*Z heterozygous alpha-1 antitrypsin states accelerate parenchymal but not biliary cirrhosis. Eur J Gastroenterol Hepatol 2014; 26:412-7. [PMID: 24518491 DOI: 10.1097/meg.0000000000000061] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
OBJECTIVE The degree to which heterozygous forms of alpha-1 antitrypsin (A1AT), principally MZ, causes liver disease is uncertain. If heterozygosity is a relevant cofactor, over-representation in patients with end-stage liver disease would be predicted. We therefore assessed the prevalence and disease-related distribution of A1AT heterozygosity in the largest cohort to date for this purpose. METHODS We retrospectively analysed 1036 patients assessed for liver transplantation at our unit between 2003 and 2010. A1AT heterozygotes were identified on the basis of isoelectric focusing and/or histology, showing A1AT globule deposition consistent with an abnormal phenotype. RESULTS Z-allele frequency was the highest in patients with nonalcoholic steatohepatitis (NASH) cirrhosis (20.3%), followed by patients with 'other parenchymal' diseases (11.9%), alcohol-related liver disease (9.9%), autoimmune disease (8.6%), hepatitis C (6.1%), hepatitis B (3.0%) and biliary disease (1.9%). Compared with the heterozygote frequency in the general European population of 9.0%, the heterozygote frequency was significantly higher among patients with NASH cirrhosis (P≤0.0001) and lower in the biliary subgroup (P=0.004). The prevalence of MZ heterozygosity was significantly increased in cirrhosis because of both alcohol (9.9%) and NASH (17.3%) compared with the general European population (2.8%; P<0.0001). CONCLUSION Accumulation of misfolded A1AT aggregates appears to accelerate progression, in which the hepatocyte is the key injured cell. Heterozygous A1AT states worsen prognosis, particularly in NASH and alcohol-related cirrhosis, and should be identified at presentation. In cases in which genetic screening is not readily available, a low threshold for isoelectric focusing and routine specific histochemical staining of liver biopsy specimens are warranted to identify these patients.
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