1
|
Ma Y, Ding Q, Qian Q, Feng L, Zhu Q, Si C, Dou X, Li S. AMPK-Regulated Autophagy Contributes to Ursolic Acid Supplementation-Alleviated Hepatic Steatosis and Liver Injury in Chronic Alcohol-Fed Mice. ACS OMEGA 2023; 8:907-914. [PMID: 36643445 PMCID: PMC9835778 DOI: 10.1021/acsomega.2c06252] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/27/2022] [Accepted: 12/08/2022] [Indexed: 06/17/2023]
Abstract
Alcoholic liver disease (ALD) is a chronic liver disease caused by long-term heavy consumption of alcohol. The pathogenesis of ALD is complex, and there is no effective clinical treatment at present. Ursolic acid (UA), a general triterpenoid with multiple biological roles, is widely distributed in plants. This study aims to explore the therapeutic effect and potential mechanisms of UA that protect against liver injury and hepatic steatosis in an ALD mouse model. In this study, we analyzed the lipid accumulation and the effect of UA treatment in a mouse model of ALD; AML12 and HepG2 cells were used to study the biological effect and potential mechanisms of UA on ethanol-induced hepatotoxicity. The morphologic and histological detections showed that UA significantly reduced alcohol-induced liver injury and hepatic steatosis. In addition, UA dramatically ameliorated alcohol-induced metabolic disorders, oxidative stress, and inflammation. Furthermore, UA treatment activated autophagy via the AMPK-ACC pathway to protect hepatocytes from lipotoxicity. Thus, these findings demonstrate that UA treatment alleviates alcoholic-induced liver injury by activating autophagy through the AMPK-ACC pathway. Therefore, UA may represent a promising candidate for the treatment of ALD.
Collapse
Affiliation(s)
- Yue Ma
- Zhejiang
Provincial Laboratory of Experimental Animal’s & Nonclinical
Laboratory Studies, Hangzhou Medical College, Hangzhou, Zhejiang 310053, PR China
| | - Qinchao Ding
- School
of Public Health, Zhejiang Chinese Medical
University, Hangzhou, Zhejiang 310053, PR China
- Institute
of Dairy Science, College of Animal Sciences, Zhejiang University, Hangzhou, Zhejiang 310058, PR China
| | - Qianyu Qian
- School
of Life Science, Zhejiang Chinese Medical
University, Hangzhou, Zhejiang 310053, PR China
| | - Luyan Feng
- School
of Life Science, Zhejiang Chinese Medical
University, Hangzhou, Zhejiang 310053, PR China
| | - Qin Zhu
- Department
of Clinical Nutrition, Zhejiang Hospital, Hangzhou, Zhejiang 310013, PR China
| | - Caijuan Si
- Department
of Clinical Nutrition, Zhejiang Hospital, Hangzhou, Zhejiang 310013, PR China
| | - Xiaobing Dou
- School
of Life Science, Zhejiang Chinese Medical
University, Hangzhou, Zhejiang 310053, PR China
| | - Songtao Li
- School
of Public Health, Zhejiang Chinese Medical
University, Hangzhou, Zhejiang 310053, PR China
- Department
of Clinical Nutrition, Zhejiang Hospital, Hangzhou, Zhejiang 310013, PR China
| |
Collapse
|
2
|
Duryee MJ, Aripova N, Hunter CD, Ruskamp RJ, Tessin MR, Works DR, Mikuls TR, Thiele GM. A novel reactive aldehyde species inhibitor prevents the deleterious effects of ethanol in an animal model of alcoholic liver disease. Int Immunopharmacol 2022; 113:109400. [DOI: 10.1016/j.intimp.2022.109400] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2022] [Revised: 10/27/2022] [Accepted: 10/27/2022] [Indexed: 11/06/2022]
|
3
|
Pan XY, Wang L, You HM, Cheng M, Yang Y, Huang C, Li J. Alternative activation of macrophages by prostacyclin synthase ameliorates alcohol induced liver injury. J Transl Med 2021; 101:1210-1224. [PMID: 34112940 PMCID: PMC8367821 DOI: 10.1038/s41374-021-00531-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Revised: 12/19/2020] [Accepted: 12/19/2020] [Indexed: 12/13/2022] Open
Abstract
Alcoholic liver disease (ALD) is a major cause of chronic liver disease worldwide. Macrophages exhibit different functional states and are classified as classically activated (M1) and alternatively activated (M2) macrophages. However, the mechanisms that govern M1/M2 polarization in chronic ALD remain to be elucidated. Prostacyclin (PGI2) synthase (PTGIS) is an enzyme of the prostaglandin pathway which catalyzes the conversion of Prostaglandin H2 (PGH2) to PGI2. PTGIS has anti-inflammatory properties. However, the function of PTGIS in ALD has not yet been determined. In this study, we demonstrated that PTGIS was downregulated in ALD and forced PTGIS expression in vivo using recombinant adeno-associated viral vector-packed PTGIS overexpression plasmid, which alleviated the inflammatory response and suppressed the macrophage M1 phenotype in mice. Loss- and gain-of function-experiments demonstrated that forced PTGIS expression inhibited the macrophage switch to the M1 phenotype and promoted M2 polarization. Furthermore, we identified the genes regulated by PTGIS through RNA-sequencing (RNA-seq) analysis. Gene ontology and KEGG pathway analyses showed that PTGIS regulates many genes involved in the immune response and is enriched in the Janus kinase/signal transducers and activators of transcription (JAK/STAT) signal transduction pathway, which plays an important role in regulating macrophage polarization. The proteins interacting with JAKs were predicted using the STRING database. The overlap between the RNA-seq and the STRING database was interleukin-6; this indicated that it was involved in macrophage polarization regulated by JAK/STAT signaling. We further explored the microRNAs that could regulate the expression of PTGIS through TargetScan. The results of luciferase assay illustrated that the expression of PTGIS was regulated by miR-140-3p.1. These results imply that PTGIS plays a pivotal role in ALD, partly by influencing macrophage polarization.
Collapse
Affiliation(s)
- Xue-Yin Pan
- Inflammation and Immune Mediated Diseases Laboratory of Anhui Province, Anhui Institute of Innovative Drugs, School of Pharmacy, Anhui Medical University, Hefei, 230032, China
- The key Laboratory of Anti-inflammatory of Immune Medicines, Ministry of Education, Hefei, 230032, China
- Institute for Liver Diseases of Anhui Medical University, Hefei, China
| | - Ling Wang
- Inflammation and Immune Mediated Diseases Laboratory of Anhui Province, Anhui Institute of Innovative Drugs, School of Pharmacy, Anhui Medical University, Hefei, 230032, China
- The key Laboratory of Anti-inflammatory of Immune Medicines, Ministry of Education, Hefei, 230032, China
- Institute for Liver Diseases of Anhui Medical University, Hefei, China
| | - Hong-Mei You
- Inflammation and Immune Mediated Diseases Laboratory of Anhui Province, Anhui Institute of Innovative Drugs, School of Pharmacy, Anhui Medical University, Hefei, 230032, China
- The key Laboratory of Anti-inflammatory of Immune Medicines, Ministry of Education, Hefei, 230032, China
- Institute for Liver Diseases of Anhui Medical University, Hefei, China
| | - Miao Cheng
- Inflammation and Immune Mediated Diseases Laboratory of Anhui Province, Anhui Institute of Innovative Drugs, School of Pharmacy, Anhui Medical University, Hefei, 230032, China
- The key Laboratory of Anti-inflammatory of Immune Medicines, Ministry of Education, Hefei, 230032, China
- Institute for Liver Diseases of Anhui Medical University, Hefei, China
| | - Yang Yang
- Inflammation and Immune Mediated Diseases Laboratory of Anhui Province, Anhui Institute of Innovative Drugs, School of Pharmacy, Anhui Medical University, Hefei, 230032, China
- The key Laboratory of Anti-inflammatory of Immune Medicines, Ministry of Education, Hefei, 230032, China
- Institute for Liver Diseases of Anhui Medical University, Hefei, China
| | - Cheng Huang
- Inflammation and Immune Mediated Diseases Laboratory of Anhui Province, Anhui Institute of Innovative Drugs, School of Pharmacy, Anhui Medical University, Hefei, 230032, China
- The key Laboratory of Anti-inflammatory of Immune Medicines, Ministry of Education, Hefei, 230032, China
- Institute for Liver Diseases of Anhui Medical University, Hefei, China
| | - Jun Li
- Inflammation and Immune Mediated Diseases Laboratory of Anhui Province, Anhui Institute of Innovative Drugs, School of Pharmacy, Anhui Medical University, Hefei, 230032, China.
- The key Laboratory of Anti-inflammatory of Immune Medicines, Ministry of Education, Hefei, 230032, China.
- Institute for Liver Diseases of Anhui Medical University, Hefei, China.
| |
Collapse
|
4
|
The Prophylactic Effects of Glutamine on Muscle Protein Synthesis and Degradation in Rats with Ethanol-Induced Liver Damage. Nutrients 2021; 13:nu13082788. [PMID: 34444950 PMCID: PMC8398394 DOI: 10.3390/nu13082788] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2021] [Revised: 08/09/2021] [Accepted: 08/12/2021] [Indexed: 12/13/2022] Open
Abstract
The purpose of this research was to investigate the prophylactic effects of glutamine on muscle protein synthesis and degradation in rats with ethanol-induced liver injury. For the first 2 weeks, Wistar rats were divided into two groups and fed a control (n = 16) or glutamine-containing diet (n = 24). For the following 6 weeks, rats fed the control diet were further divided into two groups (n = 8 per group) according to whether their diet contained no ethanol (CC) or did contain ethanol (CE). Rats fed the glutamine-containing diet were also further divided into three groups (n = 8 per group), including a GG group (glutamine-containing diet without ethanol), GE group (control diet with ethanol), and GEG group (glutamine-containing diet with ethanol). After 6 weeks, results showed that hepatic fatty change, inflammation, altered liver function, and hyperammonemia had occurred in the CE group, but these were attenuated in the GE and GEG groups. Elevated intestinal permeability and a higher plasma endotoxin level were observed in the CE group, but both were lower in the GE and GEG groups. The level of a protein synthesis marker (p70S6K) was reduced in the CE group but was higher in both the GE and GEG groups. In conclusion, glutamine supplementation might elevate muscle protein synthesis by improving intestinal health and ameliorating liver damage in rats with chronic ethanol intake.
Collapse
|
5
|
Lasebikan VO, Ige OM. Alcohol use disorders in multidrug resistant tuberculosis (MDR-TB) patients and their non-tuberculosis family contacts in Nigeria. Pan Afr Med J 2021; 36:321. [PMID: 33193975 PMCID: PMC7603812 DOI: 10.11604/pamj.2020.36.321.17118] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2018] [Accepted: 02/21/2020] [Indexed: 11/25/2022] Open
Abstract
Introduction the main aim of this study was to determine the prevalence and associated factors of alcohol use disorder (AUD) in patients with Multi-Drug Treatment-Resistant Tuberculosis (MDR-TB) compared with their non-tuberculosis control, and its association with disease pattern and associated medical comorbidities. Methods MDR-TB patients (128) and their respective caregivers were interviewed in a treatment unit in Nigeria. Diagnosis of AUD was made using the Structured Clinical Interview for DSM-IV Axis I Disorder, information was obtained on the severity of the TB and associated health problems. Results prevalence of AUD was (21.9%) and was significantly higher among cases than in controls (2.3%), p = 0.006. Severe TB, OR = 3.33 (1.56-6.83), hematological diseases, OR = 2.34 (1.06-4.33) and HIV/AIDS, OR = 3.01 (1.67-7.01) were the strongest predictors of AUD at 95% CI. Conclusion: AUD was highly prevalent in MDR-TB and was associated with certain medical comorbidities and increased severity of the illness.
Collapse
Affiliation(s)
| | - Olusoji Mayowa Ige
- Department of Medicine, College of Medicine, University of Ibadan, Ibadan, Nigeria
| |
Collapse
|
6
|
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: 17] [Impact Index Per Article: 3.4] [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.
Collapse
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
| |
Collapse
|
7
|
Georgakouli K, Manthou E, Fatouros IG, Georgoulias P, Deli CK, Koutedakis Y, Theodorakis Y, Jamurtas AZ. Enhanced erythrocyte antioxidant status following an 8-week aerobic exercise training program in heavy drinkers. Alcohol 2018; 69:57-62. [PMID: 29653379 DOI: 10.1016/j.alcohol.2017.11.035] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2017] [Revised: 11/17/2017] [Accepted: 11/22/2017] [Indexed: 12/16/2022]
Abstract
Alcohol-induced oxidative stress is involved in the development and progression of various pathological conditions and diseases. On the other hand, exercise training has been shown to improve redox status, thus attenuating oxidative stress-associated disease processes. The purpose of the present study was to evaluate the effect of an exercise training program that has been previously reported to decrease alcohol consumption on blood redox status in heavy drinkers. In a non-randomized within-subject design, 11 sedentary, heavily drinking men (age: 30.3 ± 3.5 years; BMI: 28.4 ± 0.86 kg/m2) participated first in a control condition for 4 weeks, and then in an intervention where they completed an 8-week supervised aerobic training program of moderate intensity (50-60% of the heart rate reserve). Blood samples were collected in the control condition (pre-, post-control) as well as before, during (week 4 of the training program), and after intervention (week 8 of the training program). Samples were analyzed for total antioxidant capacity (TAC), thiobarbituric acid reactive substances (TBARS), protein carbonyls (PC), uric acid (UA), bilirubin, reduced glutathione (GSH), and catalase activity. No significant change in indices of redox status in the pre- and post-control was observed. Catalase activity increased (p < 0.05) after 8 weeks of intervention compared to week 4. GSH increased (p < 0.05) after 8 weeks of intervention compared to the control condition and to week 4 of intervention. TAC, UA, bilirubin, TBARS, and PC did not significantly change at any time point. Moreover, concentrations of GSH, TBARS, and catalase activity negatively correlated with alcohol consumption. In conclusion, an 8-week aerobic training program enhanced erythrocyte antioxidant status in heavy drinkers, indicating that aerobic training may attenuate pathological processes caused by alcohol-induced oxidative stress.
Collapse
|
8
|
Different Dietary Proportions of Fish Oil Regulate Inflammatory Factors but Do Not Change Intestinal Tight Junction ZO-1 Expression in Ethanol-Fed Rats. Mediators Inflamm 2017; 2017:5801768. [PMID: 29386752 PMCID: PMC5745723 DOI: 10.1155/2017/5801768] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2017] [Revised: 09/30/2017] [Accepted: 10/15/2017] [Indexed: 12/18/2022] Open
Abstract
Sixty male Wistar rats were fed a control or an ethanol-containing diet in groups C or E. The fat compositions were adjusted with 25% or 57% fish oil substituted for olive oil in groups CF25, CF57, EF25, and EF57. Hepatic thiobarbituric acid-reactive substance (TBARS) levels, cytochrome P450 2E1 protein expression, and tumor necrosis factor- (TNF-) α, interleukin- (IL-) 1β, IL-6, and IL-10 levels, as well as intracellular adhesion molecule (ICAM)-1 levels were significantly elevated, whereas plasma adiponectin level was significantly reduced in group E (p < 0.05). Hepatic histopathological scores of fatty change and inflammation, in group E were significantly higher than those of group C (p < 0.05). Hepatic TBARS, plasma ICAM-1, and hepatic TNF-α, IL-1β, and IL-10 levels were significantly lower, and plasma adiponectin levels were significantly higher in groups EF25 and EF57 than those in group E (p < 0.05). The immunoreactive area of the intestinal tight junction protein, ZO-1, showed no change between groups C and E. Only group CF57 displayed a significantly higher ZO-1 immunoreactive area compared to group C (p = 0.0415). 25% or 57% fish oil substituted for dietary olive oil could prevent ethanol-induced liver damage in rats, but the mechanism might not be related to intestinal tight junction ZO-1 expression.
Collapse
|
9
|
Wang S, Sui S, Liu Z, Peng C, Liu J, Luo D, Fan X, Liu C, Lu WY. Protective roles of hepatic gamma-aminobutyric acid signaling in acute ethanol exposure-induced liver injury. J Appl Toxicol 2017; 38:341-350. [PMID: 29044621 DOI: 10.1002/jat.3544] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2017] [Revised: 09/03/2017] [Accepted: 09/04/2017] [Indexed: 11/06/2022]
Abstract
Alcoholic liver disease (ALD) is a consequence of heavy and prolonged alcohol consumptions. We previously demonstrated a hepatic gamma-aminobutyric acid (GABA) signaling system that protects the liver from toxic injury. The present study was designed to investigate the role of the hepatic GABA signaling system in the process of acute ethanol exposure-induced liver injury. Our results showed that the expression of GABA synthesizing enzyme glutamic acid decarboxylase and type A GABA receptor (GABAA R) subunits was upregulated in ethanol-treated mice compared with saline-treated controls. Remarkably, pretreatment of mice with GABA (1.5 mg kg-1 body weight, intraperitoneal injection [i.p.]) or with the GABAA R agonist muscimol (1.2 mg kg-1 body weight, i.p.) protected the liver against ethanol toxicity and improved liver function, whereas pretreatment of mice with the GABAA R antagonist bicuculline (2.0 mg kg-1 body weight, i.p.) worsened the liver function. Further analyses suggest that GABAA R-mediated signaling protects the liver from ethanol injury by, at least partially, inhibiting the IRE1α-ASK1-JNK pro-apoptotic pathway in hepatocytes in the process of ethanol-induced endoplasmic reticulum stress response.
Collapse
Affiliation(s)
- Shuanglian Wang
- Department of Physiology, Shandong University School of Medicine, Jinan, Shandong, People's Republic of China
| | - Shaofeng Sui
- Shandong Center for Disease Control and Prevention, Institute of Occupational and Environmental Health, Jinan, Shandong, People's Republic of China
| | - Zhiyan Liu
- Department of Pathology, Shandong University School of Medicine, Jinan, Shandong, People's Republic of China
| | - Cheng Peng
- Shandong University Qi Lu Hospital, Jinan, Shandong, People's Republic of China
| | - Jia Liu
- Xinhua Hospital, Huainan, Anhui, People's Republic of China
| | - Dan Luo
- Department of Physiology, Shandong University School of Medicine, Jinan, Shandong, People's Republic of China
| | - Xinhuan Fan
- Department of Physiology, Shandong University School of Medicine, Jinan, Shandong, People's Republic of China
| | - Chuanyong Liu
- Department of Physiology, Shandong University School of Medicine, Jinan, Shandong, People's Republic of China
| | - Wei-Yang Lu
- Department of Physiology and Pharmacology, University of Western Ontario, London, ON, Canada.,Robarts Research Institute, University of Western Ontario, London, ON, Canada
| |
Collapse
|
10
|
Kwon HJ, Won YS, Park O, Chang B, Duryee MJ, Thiele GE, Matsumoto A, Singh S, Abdelmegeed MA, Song BJ, Kawamoto T, Vasiliou V, Thiele GM, Gao B. Aldehyde dehydrogenase 2 deficiency ameliorates alcoholic fatty liver but worsens liver inflammation and fibrosis in mice. Hepatology 2014; 60:146-57. [PMID: 24492981 PMCID: PMC4077916 DOI: 10.1002/hep.27036] [Citation(s) in RCA: 135] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/11/2013] [Accepted: 01/29/2014] [Indexed: 12/14/2022]
Abstract
UNLABELLED Aldehyde dehydrogenase 2 (ALDH2) is the major enzyme that metabolizes acetaldehyde produced from alcohol metabolism. Approximately 40-50% of East Asians carry an inactive ALDH2 gene and exhibit acetaldehyde accumulation after alcohol consumption. However, the role of ALDH2 deficiency in the pathogenesis of alcoholic liver injury remains obscure. In the present study, wild-type and ALDH2(-/-) mice were subjected to ethanol feeding and/or carbon tetrachloride (CCl4 ) treatment, and liver injury was assessed. Compared with wild-type mice, ethanol-fed ALDH2(-/-) mice had higher levels of malondialdehyde-acetaldehyde (MAA) adduct and greater hepatic inflammation, with higher hepatic interleukin (IL)-6 expression but surprisingly lower levels of steatosis and serum alanine aminotransferase (ALT). Higher IL-6 levels were also detected in ethanol-treated precision-cut liver slices from ALDH2(-/-) mice and in Kupffer cells isolated from ethanol-fed ALDH2(-/-) mice than those levels in wild-type mice. In vitro incubation with MAA enhanced the lipopolysaccharide (LPS)-mediated stimulation of IL-6 production in Kupffer cells. In agreement with these findings, hepatic activation of the major IL-6 downstream signaling molecule signal transducer and activator of transcription 3 (STAT3) was higher in ethanol-fed ALDH2(-/-) mice than in wild-type mice. An additional deletion of hepatic STAT3 increased steatosis and hepatocellular damage in ALDH2(-/-) mice. Finally, ethanol-fed ALDH2(-/-) mice were more prone to CCl4 -induced liver inflammation and fibrosis than ethanol-fed wild-type mice. CONCLUSION ALDH2(-/-) mice are resistant to ethanol-induced steatosis but prone to inflammation and fibrosis by way of MAA-mediated paracrine activation of IL-6 in Kupffer cells. These findings suggest that alcohol, by way of acetaldehyde and its associated adducts, stimulates hepatic inflammation and fibrosis independent from causing hepatocyte death, and that ALDH2-deficient individuals may be resistant to steatosis and blood ALT elevation, but are prone to liver inflammation and fibrosis following alcohol consumption.
Collapse
Affiliation(s)
- Hyo-Jung Kwon
- Laboratory of Liver Diseases, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD 20892, USA,College of Veterinary Medicine, Chungnam National University, Yuseong-gu, Daejeon, South Korea
| | - Young-Suk Won
- Laboratory of Liver Diseases, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD 20892, USA,Laboratory Animal Resource Center, Korea Research Institute of Bioscience and Biotechnology, Chungbuk, South Korea
| | - Ogyi Park
- Laboratory of Liver Diseases, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD 20892, USA
| | - Binxia Chang
- Laboratory of Liver Diseases, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD 20892, USA
| | - Michael J. Duryee
- Experimental Immunology Laboratory, Omaha VA Medical Center and the University of Nebraska Medical Center, Omaha NE 68105, USA
| | - Geoffrey E. Thiele
- Experimental Immunology Laboratory, Omaha VA Medical Center and the University of Nebraska Medical Center, Omaha NE 68105, USA
| | - Akiko Matsumoto
- Department of Social Medicine, Saga University School of Medicine, Saga 849-0935, Japan
| | - Surendra Singh
- Department of Pharmaceutical Sciences, University of Colorado, Aurora, CO 80045, USA
| | - Mohamed A. Abdelmegeed
- Section of Molecular Pharmacology and Toxicology, Laboratory of Membrane Biochemistry and Biophysics, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD 20892, USA
| | - Byoung-Joon Song
- Section of Molecular Pharmacology and Toxicology, Laboratory of Membrane Biochemistry and Biophysics, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD 20892, USA
| | - Toshihiro Kawamoto
- Department of Environmental Health, University of Occupational and Environmental Health, 1-1 Iseigaoka, Yahatanishi-ku, Kitakyushu 807-8555, Japan
| | - Vasilis Vasiliou
- Department of Pharmaceutical Sciences, University of Colorado, Aurora, CO 80045, USA
| | - Geoffrey M. Thiele
- Experimental Immunology Laboratory, Omaha VA Medical Center and the University of Nebraska Medical Center, Omaha NE 68105, USA
| | - Bin Gao
- Laboratory of Liver Diseases, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD 20892, USA
| |
Collapse
|
11
|
Li HH, Tyburski JB, Wang YW, Strawn S, Moon BH, Kallakury BVS, Gonzalez FJ, Fornace AJ. Modulation of fatty acid and bile acid metabolism by peroxisome proliferator-activated receptor α protects against alcoholic liver disease. Alcohol Clin Exp Res 2014; 38:1520-31. [PMID: 24773203 DOI: 10.1111/acer.12424] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2013] [Accepted: 03/14/2014] [Indexed: 12/20/2022]
Abstract
BACKGROUND Chronic alcohol intake affects liver function and causes hepatic pathological changes. It has been shown that peroxisome proliferator-activated receptor α (PPARα)-null mice developed more pronounced hepatic changes than wild-type (WT) mice after chronic exposure to a diet containing 4% alcohol. The remarkable similarity between the histopathology of alcoholic liver disease (ALD) in Ppara-null model and in humans, and the fact that PPARα expression and activity in human liver are less than one-tenth of those in WT mouse liver make Ppara-null a good system to investigate ALD. METHODS In this study, the Ppara-null model was used to elucidate the dynamic regulation of PPARα activity during chronic alcohol intake. Hepatic transcriptomic and metabolomic analyses were used to examine alterations of gene expression and metabolites associated with pathological changes. The changes triggered by alcohol consumption on gene expression and metabolites in Ppara-null mice were compared with those in WT mice. RESULTS The results showed that in the presence of PPARα, 3 major metabolic pathways in mitochondria, namely the fatty acid β-oxidation, the tricarboxylic acid cycle, and the electron transfer chain, were induced in response to a 2-month alcohol feeding, while these responses were greatly reduced in the absence of PPARα. In line with the transcriptional modulations of these metabolic pathways, a progressive accumulation of triglycerides, a robust increase in hepatic cholic acid and its derivatives, and a strong induction of fibrogenesis genes were observed exclusively in alcohol-fed Ppara-null mice. CONCLUSIONS These observations indicate that PPARα plays a protective role to enhance mitochondrial function in response to chronic alcohol consumption by adaptive transcriptional activation and suggest that activation of this nuclear receptor may be of therapeutic value in the treatment for ALD.
Collapse
Affiliation(s)
- Heng-Hong Li
- Department of Biochemistry and Molecular & Cellular Biology, Georgetown University, Washington, District of Columbia
| | | | | | | | | | | | | | | |
Collapse
|
12
|
GAO BIN, BATALLER RAMON. Alcoholic liver disease: pathogenesis and new therapeutic targets. Gastroenterology 2011; 141:1572-85. [PMID: 21920463 PMCID: PMC3214974 DOI: 10.1053/j.gastro.2011.09.002] [Citation(s) in RCA: 1353] [Impact Index Per Article: 104.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/13/2011] [Revised: 09/08/2011] [Accepted: 09/08/2011] [Indexed: 02/07/2023]
Abstract
Alcoholic liver disease (ALD) is a major cause of chronic liver disease worldwide and can lead to fibrosis and cirrhosis. The latest surveillance report published by the National Institute on Alcohol Abuse and Alcoholism showed that liver cirrhosis was the 12th leading cause of death in the United States, with a total of 29,925 deaths in 2007, 48% of which were alcohol related. The spectrum of ALD includes simple steatosis, alcoholic hepatitis, fibrosis, cirrhosis, and superimposed hepatocellular carcinoma. Early work on the pathogenesis of the disease focused on ethanol metabolism-associated oxidative stress and glutathione depletion, abnormal methionine metabolism, malnutrition, and production of endotoxins that activate Kupffer cells. We review findings from recent studies that have characterized specific intracellular signaling pathways, transcriptional factors, aspects of innate immunity, chemokines, epigenetic features, microRNAs, and stem cells that are associated with ALD, improving our understanding of its pathogenesis. Despite this progress, no targeted therapies are available. The cornerstone of treatment for alcoholic hepatitis remains as it was 40 years ago: abstinence, nutritional support, and corticosteroids. There is an urgent need to develop new pathophysiology-oriented therapies. Recent translational studies of human samples and animal models have identified promising therapeutic targets.
Collapse
Affiliation(s)
- BIN GAO
- Laboratory of Liver Diseases, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, Maryland
| | - RAMON BATALLER
- Liver Unit, Hospital Clínic, Institut d’Investigacions Biomèdiques August Pi i Sunyer, Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas, Barcelona, Catalonia, Spain
| |
Collapse
|
13
|
Gwoździński Ł, Krawczyk P, Dworniak D, Kowalczyk E, Błaszczyk J. Alterations in the erythrocyte plasma membranes in patients with alcohol-induced liver cirrhosis - preliminary results. Arch Med Sci 2011; 7:87-91. [PMID: 22291738 PMCID: PMC3258700 DOI: 10.5114/aoms.2011.20609] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/11/2010] [Revised: 03/26/2010] [Accepted: 05/05/2010] [Indexed: 11/18/2022] Open
Abstract
INTRODUCTION Conformations of membrane proteins, membrane fluidity of erythrocytes in patients with AILC were studied with the use of electron paramagnetic resonance and spectrophotometric methods. The concentration of substances reacting with thiobarbituric acid was also determined. The aim of the study was to recognize the nature, level and causes of changes in the structure of erythrocytary membrane observed in erythrocytes of patients compared to erythrocytes from healthy controls. MATERIAL AND METHODS SPIN LABELS: MSL and ISL binding covalently to thiol groups of membrane cytoskeleton proteins were used to analyse modifications occurring in erythrocytary membrane proteins. Doxyl derivatives of fatty acids: 5-DS, 12-DS and 16-DS binding hydrophobically to erythrocytary membrane were used as spin labels for the analysis of erythrocyte membrane lipid fluidity. RESULTS Modification of membrane cytoskeleton proteins and increase of membrane lipids fluidity were observed in erythrocytes of the investigated patients. An increase of the concentration of substances reacting with thiobarbituric acid was also confirmed in the erythrocytes of AILC patients. CONCLUSIONS Observed disorders in the structure of erythrocyte cytoskeleton proteins in patients, which might developed as a consequence of oxidative stress may be conformation changes in the structure of proteins which affect membrane cytoskeleton. The differences in the structure of membrane proteins could be associated with an increase in membrane lipids fluidity. Increased fluidity of erythrocyte membrane may be a result of disorders in protein-lipid interaction or membrane lipid peroxidation activity.
Collapse
Affiliation(s)
| | - Piotr Krawczyk
- Department of Infectious Diseases, Medical University of Lodz, Poland
| | - Daniela Dworniak
- Department of Infectious Diseases, Medical University of Lodz, Poland
| | - Edward Kowalczyk
- Department of Pharmacology and Toxicology, Medical University of Lodz, Poland
| | - Jan Błaszczyk
- Department of Physiology, Medical University of Lodz, Poland
| |
Collapse
|
14
|
Manna SK, Patterson AD, Yang Q, Krausz KW, Li H, Idle JR, Fornace AJ, Gonzalez FJ. Identification of noninvasive biomarkers for alcohol-induced liver disease using urinary metabolomics and the Ppara-null mouse. J Proteome Res 2010; 9:4176-88. [PMID: 20540569 DOI: 10.1021/pr100452b] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Alcohol-induced liver disease (ALD) is a leading cause of nonaccident-related deaths in the United States. Although liver damage caused by ALD is reversible when discovered at the earlier stages, current risk assessment tools are relatively nonspecific. Identification of an early specific signature of ALD would aid in therapeutic intervention and recovery. In this study, the metabolic changes associated with ALD were examined using alcohol-fed male Ppara-null mouse as a model of ALD. Principal components analysis of the mass spectrometry-based urinary metabolic profile showed that alcohol-treated wild-type and Ppara-null mice could be distinguished from control animals without information on history of alcohol consumption. The urinary excretion of ethyl-sulfate, ethyl-beta-d-glucuronide, 4-hydroxyphenylacetic acid, and 4-hydroxyphenylacetic acid sulfate was elevated and that of the 2-hydroxyphenylacetic acid, adipic acid, and pimelic acid was depleted during alcohol treatment in both wild-type and the Ppara-null mice albeit to different extents. However, indole-3-lactic acid was exclusively elevated by alcohol exposure in Ppara-null mice. The elevation of indole-3-lactic acid is mechanistically related to the molecular events associated with development of ALD in alcohol-treated Ppara-null mice. This study demonstrated the ability of a metabolomics approach to identify early, noninvasive biomarkers of ALD pathogenesis in Ppara-null mouse model.
Collapse
Affiliation(s)
- Soumen K Manna
- Laboratory of Metabolism, Center for Cancer Research, National Cancer Institute, Bethesda, Maryland 20852, USA
| | | | | | | | | | | | | | | |
Collapse
|
15
|
Mutlu E, Keshavarzian A, Engen P, Forsyth CB, Sikaroodi M, Gillevet P. Intestinal dysbiosis: a possible mechanism of alcohol-induced endotoxemia and alcoholic steatohepatitis in rats. Alcohol Clin Exp Res 2009; 33:1836-46. [PMID: 19645728 DOI: 10.1111/j.1530-0277.2009.01022.x] [Citation(s) in RCA: 270] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
BACKGROUND Clinical and animal data indicate that gut-derived endotoxin and other luminal bacterial products are necessary cofactors for development of alcoholic liver disease (ALD). Although gut leakiness is clearly an important cause of endotoxemia in ALD, it cannot fully explain endotoxemia in all ALD subjects and thus other factors may be involved. One possible factor is a change in gut microbiota composition (dysbiosis). Thus, the aim of our study was to interrogate the gut bacterial microbiota in alcohol-fed rats to see if chronic alcohol consumption affects gut bacteria composition. METHOD Male Sprague-Dawley rats were given either alcohol or dextrose intragastrically by gavage twice daily for up to 10 weeks. A subgroup of rats was also given either a probiotic (lactobacillus GG) or a prebiotic (oats) by gavage. Ileal and colonic mucosal-attached microbiota composition were interrogated by Length Heterogeneity PCR (LH-PCR) fingerprinting. RESULTS Bacterial microbiota composition in alcohol-fed rats is not different from dextrose-fed rats at weeks 4 and 6. Mucosa-associated microbiota composition in the colon is altered at 10 weeks of daily alcohol gavage. Both LGG and oats prevented alcohol-induced dysbiosis up to 10 weeks of alcohol treatment. CONCLUSION Daily alcohol consumption for 10 weeks alters colonic mucosa-associated bacterial microbiota composition in rats. Our data showed, for the first time, that daily alcohol consumption can affect colonic microbiome composition and suggest that dysbiosis may be an important mechanism of alcohol-induced endotoxemia. Further studies are needed to determine how dysbiotic microbiota contributes to development of ALD and whether therapeutic interventions targeted towards dysbiotic microbiota can prevent complications of alcoholism like ALD.
Collapse
Affiliation(s)
- Ece Mutlu
- Rush University Medical Center, Division of Digestive Diseases and Nutrition, Nutrition Rush University Medical Center, Chicago, Illinois 60612, USA
| | | | | | | | | | | |
Collapse
|
16
|
Mutlu E, Keshavarzian A, Engen P, Forsyth CB, Sikaroodi M, Gillevet P. Intestinal dysbiosis: a possible mechanism of alcohol-induced endotoxemia and alcoholic steatohepatitis in rats. Alcohol Clin Exp Res 2009. [PMID: 19645728 DOI: 10.1111/j.1530-0277.2009.01022] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
BACKGROUND Clinical and animal data indicate that gut-derived endotoxin and other luminal bacterial products are necessary cofactors for development of alcoholic liver disease (ALD). Although gut leakiness is clearly an important cause of endotoxemia in ALD, it cannot fully explain endotoxemia in all ALD subjects and thus other factors may be involved. One possible factor is a change in gut microbiota composition (dysbiosis). Thus, the aim of our study was to interrogate the gut bacterial microbiota in alcohol-fed rats to see if chronic alcohol consumption affects gut bacteria composition. METHOD Male Sprague-Dawley rats were given either alcohol or dextrose intragastrically by gavage twice daily for up to 10 weeks. A subgroup of rats was also given either a probiotic (lactobacillus GG) or a prebiotic (oats) by gavage. Ileal and colonic mucosal-attached microbiota composition were interrogated by Length Heterogeneity PCR (LH-PCR) fingerprinting. RESULTS Bacterial microbiota composition in alcohol-fed rats is not different from dextrose-fed rats at weeks 4 and 6. Mucosa-associated microbiota composition in the colon is altered at 10 weeks of daily alcohol gavage. Both LGG and oats prevented alcohol-induced dysbiosis up to 10 weeks of alcohol treatment. CONCLUSION Daily alcohol consumption for 10 weeks alters colonic mucosa-associated bacterial microbiota composition in rats. Our data showed, for the first time, that daily alcohol consumption can affect colonic microbiome composition and suggest that dysbiosis may be an important mechanism of alcohol-induced endotoxemia. Further studies are needed to determine how dysbiotic microbiota contributes to development of ALD and whether therapeutic interventions targeted towards dysbiotic microbiota can prevent complications of alcoholism like ALD.
Collapse
Affiliation(s)
- Ece Mutlu
- Rush University Medical Center, Division of Digestive Diseases and Nutrition, Nutrition Rush University Medical Center, Chicago, Illinois 60612, USA
| | | | | | | | | | | |
Collapse
|
17
|
Fernández A, Colell A, Caballero F, Matías N, García-Ruiz C, Fernández-Checa JC. Mitochondrial S-adenosyl-L-methionine transport is insensitive to alcohol-mediated changes in membrane dynamics. Alcohol Clin Exp Res 2009; 33:1169-80. [PMID: 19389197 DOI: 10.1111/j.1530-0277.2009.00940.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
BACKGROUND Alcohol-induced liver injury is associated with decreased S-adenosyl-l-methionine (SAM)/S-adenosyl-l-homocysteine (SAH) ratio and mitochondrial glutathione (mGSH) depletion, which has been shown to sensitize hepatocytes to tumor necrosis factor (TNF). AIMS As the effect of alcohol on mitochondrial SAM (mSAM) has been poorly characterized, our aim was to examine the status and transport of mSAM in relation to that of mGSH during alcohol intake. METHODS Sprague-Dawley rats were pair fed Lieber-DeCarli diets containing alcohol for 1 to 4 weeks and liver fractionated into cytosol and mitochondria to examine the mSAM transport and its sensitivity to membrane dynamics. RESULTS We found that cytosol SAM was depleted from the first week of alcohol feeding, with mSAM levels paralleling these changes. Cytosol SAH, however, increased during the first 3 weeks of alcohol intake, whereas its mitochondrial levels remained unchanged. mGSH depletion occurred by 3 to 4 weeks of alcohol intake due to cholesterol-mediated impaired transport from the cytosol. In contrast to this outcome, the transport of SAM into hepatic mitochondria was unaffected by alcohol intake and resistant to cholesterol-mediated perturbations in membrane dynamics; furthermore cytosolic SAH accumulation in primary hepatocytes by SAH hydrolase inhibition reproduced the mSAM depletion by alcohol due to the competition of SAH with SAM for mitochondrial transport. However, alcohol feeding did not potentiate the sensitivity to inhibition by SAH accumulation. CONCLUSIONS Alcohol-induced mSAM depletion precedes that of mGSH and occurs independently of alcohol-mediated perturbations in membrane dynamics, disproving an inherent defect in the mSAM transport by alcohol. These findings suggest that the early mSAM depletion may contribute to the alterations of mitochondrial membrane dynamics and the subsequent mGSH down-regulation induced by alcohol feeding.
Collapse
Affiliation(s)
- Anna Fernández
- Liver Unit and Centro de Investigaciones Biomédicas Esther Koplowitz, Instituto Investigaciones Biomédicas de Barcelona, Consejo Superior de Investigaciones Científicas, Barcelona, Spain
| | | | | | | | | | | |
Collapse
|
18
|
Forsyth CB, Farhadi A, Jakate SM, Tang Y, Shaikh M, Keshavarzian A. Lactobacillus GG treatment ameliorates alcohol-induced intestinal oxidative stress, gut leakiness, and liver injury in a rat model of alcoholic steatohepatitis. Alcohol 2009; 43:163-72. [PMID: 19251117 DOI: 10.1016/j.alcohol.2008.12.009] [Citation(s) in RCA: 293] [Impact Index Per Article: 19.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2008] [Revised: 12/31/2008] [Accepted: 12/31/2008] [Indexed: 02/06/2023]
Abstract
Because only 30% of alcoholics develop alcoholic liver disease (ALD), a factor other than heavy alcohol consumption must be involved in the development of alcohol-induced liver injury. Animal and human studies suggest that bacterial products, such as endotoxins, are the second key co-factors, and oxidant-mediated gut leakiness is one of the sources of endotoxemia. Probiotics have been used to prevent and treat diseases associated with gut-derived bacterial products and disorders associated with gut leakiness. Indeed, "probiotic"Lactobacillus rhamnosus has been successfully used to treat alcohol-induced liver injury in rats. However, the mechanism of action involved in the potential beneficial effects of L. rhamnosus in alcohol liver injury is not known. We hypothesized that probiotics could preserve normal barrier function in an animal model of ALD by preventing alcohol-induced oxidative stress and thus prevent the development of hyperpermeability and subsequent alcoholic steatohepatitis (ASH). Male Sprague-Dawley rats were gavaged with alcohol twice daily (8 gm/kg) for 10 weeks. In addition, alcoholic rats were also treated with once daily gavage of either 2.5 x 10(7) live L. rhamnosus Gorbach-Goldin (LGG) or vehicle (V). Intestinal permeability (baseline and at 10 weeks) was determined using a sugar bolus and GC analysis of urinary sugars. Intestinal and liver tissues were analyzed for markers of oxidative stress and inflammation. In addition, livers were assessed histologically for severity of ASH and total fat (steatosis). Alcohol+LGG (ALC+LGG)-fed rats had significantly (P< or =.05) less severe ASH than ALC+V-fed rats. L. rhamnosus Gorbach-Goldin also reduced alcohol-induced gut leakiness and significantly blunted alcohol-induced oxidative stress and inflammation in both intestine and the liver. L. rhamnosus Gorbach-Goldin probiotic gavage significantly ameliorated ASH in rats. This improvement was associated with reduced markers of intestinal and liver oxidative stress and inflammation and preserved gut barrier function. Our study provides a scientific rationale to test probiotics for treatment and/or prevention of alcoholic liver disease in man.
Collapse
Affiliation(s)
- Christopher B Forsyth
- Department of Internal Medicine, Division of Digestive Diseases and Nutrition, and Rush University Medical Center, 1725 W. Harrison, Suite 206, Chicago, IL 60612, USA
| | | | | | | | | | | |
Collapse
|
19
|
Fernández A, Colell A, Garcia-Ruiz C, Fernandez-Checa JC. Cholesterol and sphingolipids in alcohol-induced liver injury. J Gastroenterol Hepatol 2008; 23 Suppl 1:S9-15. [PMID: 18336673 DOI: 10.1111/j.1440-1746.2007.05280.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The pathogenesis of alcohol-induced liver disease (ALD) is still poorly understood. One of the clues to its progression relates to the alcohol-mediated susceptibility of hepatocytes to cell death by reactive oxygen species (ROS) and inflammatory cytokines. Tumor necrosis factor alpha (TNF) has been considered a key ALD mediator with acidic sphingomyelinase (ASMase)-mediated ceramide generation playing a critical role. TNF receptor 1 and 2 knock-out mice or ASMase(-/-) mice exhibit resistance to alcohol-mediated fatty liver and cell death. Furthermore, alcohol feeding has been shown to sensitize hepatocytes to TNF due to the limitation of mitochondrial glutathione (mGSH) through impaired import of GSH from the cytosol due to altered membrane order parameter caused by mitochondrial cholesterol increase. Selective pharmacological depletion of mGSH sensitizes hepatocytes to TNF-mediated cell death, which reproduces the observations found with alcohol feeding. TNF signaling analyses in hepatocytes with or without mGSH depletion indicate that mGSH prevents cardiolipin peroxidation (CLOOH) formation by TNF-induced ROS via ASMase and that CLOOH cooperates with oligomerized Bax to cause mitochondrial outer membrane permeabilization through destabilization of the lipid bilayer via increased bilayer-to-inverted hexagonal phase transitions. Thus, activation of ASMase and cholesterol-mediated mGSH depletion both collaborate to promote alcohol-induced TNF-mediated hepatocellular damage, suggesting novel therapeutic opportunities in ALD.
Collapse
Affiliation(s)
- Anna Fernández
- Center for Biomedical Research Esther Koplowitz, IMDiM, Hospital Clinic and CIBEREHD, Institute of Biomedical Research August Pi i Sunyer, Department of Cell Death and Proliferation, Institute of Biomedical Research, Barcelona, Spain
| | | | | | | |
Collapse
|
20
|
Horiguchi N, Ishac EJN, Gao B. Liver regeneration is suppressed in alcoholic cirrhosis: correlation with decreased STAT3 activation. Alcohol 2007; 41:271-80. [PMID: 17630087 PMCID: PMC1986734 DOI: 10.1016/j.alcohol.2007.04.008] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2007] [Revised: 04/18/2007] [Accepted: 04/18/2007] [Indexed: 02/06/2023]
Abstract
UNLABELLED Liver regeneration is suppressed in alcoholic patients; however, the underlying mechanisms are not fully understood. We examined liver regeneration and signal transducer and activator of transcription 3 (STAT3) activation (an important signal for liver regeneration) in cirrhotic livers from alcoholics, hepatitis C virus (HCV) infection, and alcoholic plus HCV infection. Liver regeneration and STAT3 activation were determined by immunohistochemistry analysis of Ki67 and STAT3 phosphorylation, respectively, in 20 alcoholic cirrhosis, 13 HCV cirrhosis, 13 alcoholic+HCV cirrhosis. Alcoholic or alcoholic plus HCV cirrhotic livers had significantly lower Ki67+ and phospho-STAT3+ (pSTAT3+) hepatocytes and bile duct cells than HCV cirrhotic livers. The pSTAT3 positive staining did not correlate with liver injury (elevation of serum levels of aspartate transaminase [AST] and alkaline phosphatase [ALP]) but correlated positively with cell proliferation (Ki67 positive staining). IN CONCLUSION liver regeneration is suppressed in alcoholic cirrhotic livers, which may be partly due to decreased STAT3 activation.
Collapse
Affiliation(s)
- Norio Horiguchi
- Section on Liver Biology, Laboratory of Physiologic Studies, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD 20892
| | - Edward JN Ishac
- Department of Pharmacology and Toxicology, Virginia Commonwealth University School of Medicine, Richmond, VA 23298
| | - Bin Gao
- Section on Liver Biology, Laboratory of Physiologic Studies, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD 20892
| |
Collapse
|
21
|
Zinchuk V, Zinchuk O, Akimaru K, Moriya F, Okada T. Ethanol consumption alters expression and colocalization of bile salt export pump and multidrug resistance protein 2 in the rat. Histochem Cell Biol 2007; 127:503-12. [PMID: 17384956 DOI: 10.1007/s00418-007-0277-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/07/2007] [Indexed: 02/01/2023]
Abstract
Chronic ethanol consumption elicits detrimental changes of liver metabolism. By employing a 12-week-long feeding regimen, we investigated the effects of chronic ethanol consumption on the expression and localization of bile salt export pump (Bsep), a major canalicular exporter of bile salts, and multidrug resistance protein 2 (Mrp2), a canalicular organic anion transporter, in the rat liver. RT-PCR, confocal immunofluorescence microscopy, immunoblotting, and quantitative colocalization analysis were used to examine their gene and protein expression, and changes in the distribution of antigenic sites. Bsep mRNA was upregulated, while Mrp2 mRNA responded by downregulation. In agreement with mRNA, the expression of Bsep protein increased, while the expression of Mrp2 protein responded with a decrease, suggesting that the expression of both of them is transcriptionally regulated. Confocal immunofluorescence microscopy showed disruption of the colocalization of Bsep and Mrp2 proteins at the hepatocyte canalicular membrane and their relocation intracellularly. Quantitative colocalization analysis of Bsep and Mrp2 proteins revealed a steady decrease in the degree of colocalization and Mrp2 expression, indicating that although the properties of both transporters are affected, Mrp2 is altered more. These findings provide evidence that ethanol alters Bsep and Mrp2 canalicular transporters in the rat liver, at both the mRNA and protein levels. Mrp2 shows deeper involvement. Eight weeks appears to be a critical time point in this process.
Collapse
Affiliation(s)
- Vadim Zinchuk
- Department of Anatomy and Cell Biology, Kochi University Faculty of Medicine, Kohasu, Okoh-cho, Nankoku, Kochi, 783-8505, Japan.
| | | | | | | | | |
Collapse
|
22
|
|
23
|
Keshavarzian A, Fields J. Alcoholic liver disease: is it an "extraintestinal" complication of alcohol-induced intestinal injury? ACTA ACUST UNITED AC 2004; 142:285-7. [PMID: 14647031 DOI: 10.1016/s0022-2143(03)00140-9] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|