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LeFort KR, Rungratanawanich W, Song BJ. Contributing roles of mitochondrial dysfunction and hepatocyte apoptosis in liver diseases through oxidative stress, post-translational modifications, inflammation, and intestinal barrier dysfunction. Cell Mol Life Sci 2024; 81:34. [PMID: 38214802 PMCID: PMC10786752 DOI: 10.1007/s00018-023-05061-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2023] [Revised: 11/16/2023] [Accepted: 11/22/2023] [Indexed: 01/13/2024]
Abstract
This review provides an update on recent findings from basic, translational, and clinical studies on the molecular mechanisms of mitochondrial dysfunction and apoptosis of hepatocytes in multiple liver diseases, including but not limited to alcohol-associated liver disease (ALD), metabolic dysfunction-associated steatotic liver disease (MASLD), and drug-induced liver injury (DILI). While the ethanol-inducible cytochrome P450-2E1 (CYP2E1) is mainly responsible for oxidizing binge alcohol via the microsomal ethanol oxidizing system, it is also responsible for metabolizing many xenobiotics, including pollutants, chemicals, drugs, and specific diets abundant in n-6 fatty acids, into toxic metabolites in many organs, including the liver, causing pathological insults through organelles such as mitochondria and endoplasmic reticula. Oxidative imbalances (oxidative stress) in mitochondria promote the covalent modifications of lipids, proteins, and nucleic acids through enzymatic and non-enzymatic mechanisms. Excessive changes stimulate various post-translational modifications (PTMs) of mitochondrial proteins, transcription factors, and histones. Increased PTMs of mitochondrial proteins inactivate many enzymes involved in the reduction of oxidative species, fatty acid metabolism, and mitophagy pathways, leading to mitochondrial dysfunction, energy depletion, and apoptosis. Unique from other organelles, mitochondria control many signaling cascades involved in bioenergetics (fat metabolism), inflammation, and apoptosis/necrosis of hepatocytes. When mitochondrial homeostasis is shifted, these pathways become altered or shut down, likely contributing to the death of hepatocytes with activation of inflammation and hepatic stellate cells, causing liver fibrosis and cirrhosis. This review will encapsulate how mitochondrial dysfunction contributes to hepatocyte apoptosis in several types of liver diseases in order to provide recommendations for targeted therapeutics.
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Affiliation(s)
- Karli R LeFort
- Section of Molecular Pharmacology and Toxicology, National Institute on Alcohol Abuse and Alcoholism, 9000 Rockville Pike, Bethesda, MD, 20892, USA.
| | - Wiramon Rungratanawanich
- Section of Molecular Pharmacology and Toxicology, National Institute on Alcohol Abuse and Alcoholism, 9000 Rockville Pike, Bethesda, MD, 20892, USA
| | - Byoung-Joon Song
- Section of Molecular Pharmacology and Toxicology, National Institute on Alcohol Abuse and Alcoholism, 9000 Rockville Pike, Bethesda, MD, 20892, USA.
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LeFort KR, Rungratanawanich W, Song BJ. Melatonin Prevents Alcohol- and Metabolic Dysfunction- Associated Steatotic Liver Disease by Mitigating Gut Dysbiosis, Intestinal Barrier Dysfunction, and Endotoxemia. Antioxidants (Basel) 2023; 13:43. [PMID: 38247468 PMCID: PMC10812487 DOI: 10.3390/antiox13010043] [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: 11/21/2023] [Revised: 12/19/2023] [Accepted: 12/22/2023] [Indexed: 01/23/2024] Open
Abstract
Melatonin (MT) has often been used to support good sleep quality, especially during the COVID-19 pandemic, as many have suffered from stress-related disrupted sleep patterns. It is less known that MT is an antioxidant, anti-inflammatory compound, and modulator of gut barrier dysfunction, which plays a significant role in many disease states. Furthermore, MT is produced at 400-500 times greater concentrations in intestinal enterochromaffin cells, supporting the role of MT in maintaining the functions of the intestines and gut-organ axes. Given this information, the focus of this article is to review the functions of MT and the molecular mechanisms by which it prevents alcohol-associated liver disease (ALD) and metabolic dysfunction-associated steatotic liver disease (MASLD), including its metabolism and interactions with mitochondria to exert its antioxidant and anti-inflammatory activities in the gut-liver axis. We detail various mechanisms by which MT acts as an antioxidant, anti-inflammatory compound, and modulator of intestinal barrier function to prevent the progression of ALD and MASLD via the gut-liver axis, with a focus on how these conditions are modeled in animal studies. Using the mechanisms of MT prevention and animal studies described, we suggest behavioral modifications and several exogenous sources of MT, including food and supplements. Further clinical research should be performed to develop the field of MT in preventing the progression of liver diseases via the gut-liver axis, so we mention a few considerations regarding MT supplementation in the context of clinical trials in order to advance this field of research.
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Affiliation(s)
- Karli R. LeFort
- Section of Molecular Pharmacology and Toxicology, National Institute on Alcohol Abuse and Alcoholism, 9000 Rockville Pike, Bethesda, MD 20892, USA;
| | | | - Byoung-Joon Song
- Section of Molecular Pharmacology and Toxicology, National Institute on Alcohol Abuse and Alcoholism, 9000 Rockville Pike, Bethesda, MD 20892, USA;
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Kim DH, Kim JS, Kwon JH, Kwun IS, Baek MC, Kwon GS, Rungratanawanich W, Song BJ, Kim DK, Kwon HJ, Cho YE. Ellagic Acid Prevented Dextran-Sodium-Sulfate-Induced Colitis, Liver, and Brain Injury through Gut Microbiome Changes. Antioxidants (Basel) 2023; 12:1886. [PMID: 37891965 PMCID: PMC10604018 DOI: 10.3390/antiox12101886] [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: 08/23/2023] [Revised: 10/11/2023] [Accepted: 10/11/2023] [Indexed: 10/29/2023] Open
Abstract
Inflammatory bowel disease (IBD) affects millions of people worldwide and is considered a significant risk factor for colorectal cancer. Recent in vivo and in vitro studies reported that ellagic acid (EA) exhibits important antioxidant and anti-inflammatory properties. In this study, we investigated the preventive effects of EA against dextran sulfate sodium (DSS)-induced acute colitis, liver, and brain injury in mice through the gut-liver-brain axis. Acute colitis, liver, and brain injury were induced by treatment with 5% (w/v) DSS in the drinking water for 7 days. Freshly prepared EA (60 mg/kg/day) was orally administered, while control (CON) group mice were treated similarly by daily oral administrations with a vehicle (water). All the mice were euthanized 24 h after the final treatment with EA. The blood, liver, colon, and brain samples were collected for further histological and biochemical analyses. Co-treatment with a physiologically relevant dose (60 mg/kg/day) of EA for 7 days significantly reduced the DSS-induced gut barrier dysfunction; endotoxemia; and inflammatory gut, liver, and brain injury in mice by modulating gut microbiota composition and inhibiting the elevated oxidative and nitrative stress marker proteins. Our results further demonstrated that the preventive effect of EA on the DSS-induced IBD mouse model was mediated by blocking the NF-κB and mitogen-activated protein kinase (MAPK) pathway. Therefore, EA co-treatment significantly attenuated the pro-inflammatory and oxidative stress markers by suppressing the activation of NF-κB/MAPK pathways in gut, liver, and brain injury. These results suggest that EA, effective in attenuating IBD in a mouse model, deserves further consideration as a potential therapeutic for the treatment of inflammatory diseases.
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Affiliation(s)
- Dong-ha Kim
- Department of Molecular Medicine, School of Medicine, Cell & Matrix Research Institute, Kyungpook National University, Daegu 41566, Republic of Korea; (D.-h.K.); (M.-C.B.)
| | - Ji-Su Kim
- Department of Food and Nutrition, Andong National University, Andong 1375, Republic of Korea; (J.-S.K.); (J.-H.K.); (I.-S.K.)
| | - Jae-Hee Kwon
- Department of Food and Nutrition, Andong National University, Andong 1375, Republic of Korea; (J.-S.K.); (J.-H.K.); (I.-S.K.)
| | - In-Sook Kwun
- Department of Food and Nutrition, Andong National University, Andong 1375, Republic of Korea; (J.-S.K.); (J.-H.K.); (I.-S.K.)
| | - Moon-Chang Baek
- Department of Molecular Medicine, School of Medicine, Cell & Matrix Research Institute, Kyungpook National University, Daegu 41566, Republic of Korea; (D.-h.K.); (M.-C.B.)
| | - Gi-Seok Kwon
- Department of Horticulture & Medicinal Plant, Andong National University, Andong 1375, Republic of Korea;
| | - Wiramon Rungratanawanich
- 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; (W.R.); (B.-J.S.)
| | - 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; (W.R.); (B.-J.S.)
| | - Do-Kyun Kim
- Korea Zoonosis Research Institute, Jeonbuk National University, Iksan 54596, Republic of Korea;
| | - Hyo-Jung Kwon
- Department of Veterinary Pathology, College of Veterinary Medicine, Chungnam National University, Daejeon 34134, Republic of Korea
| | - Young-Eun Cho
- Department of Food and Nutrition, Andong National University, Andong 1375, Republic of Korea; (J.-S.K.); (J.-H.K.); (I.-S.K.)
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Zhang D, Liu Z, Bai F. Roles of Gut Microbiota in Alcoholic Liver Disease. Int J Gen Med 2023; 16:3735-3746. [PMID: 37641627 PMCID: PMC10460590 DOI: 10.2147/ijgm.s420195] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2023] [Accepted: 08/10/2023] [Indexed: 08/31/2023] Open
Abstract
Alcoholic liver disease (ALD)-one of the most common liver diseases - involves a wide range of disorders, including asymptomatic hepatic steatosis, alcoholic hepatitis (AH), liver fibrosis, and cirrhosis. Alcohol consumption induces a weakened gut barrier and changes in the composition of the gut microbiota. The presence of CYP2E1 and its elevated levels in the gastrointestinal tract after alcohol exposure lead to elevated levels of ROS and acetaldehyde, inducing inflammation and oxidative damage in the gut. At the same time, the influx of harmful molecules such as the bacterial endotoxin LPS and peptidogly from gut dysbiosis can induce intestinal inflammation and oxidative damage, further compromising the intestinal mucosal barrier. In this process, various oxidative stress-mediated post-translational modifications (PTMs) play an important role in the integrity of the barrier, eg, the presence of acetaldehyde will result in the sustained phosphorylation of several paracellular proteins (occludin and zona occludens-1), which can lead to intestinal leakage. Eventually, persistent oxidative stress, LPS infiltration and hepatocyte damage through the enterohepatic circulation will lead to hepatic stellate cell activation and hepatic fibrosis. In addition, probiotics, prebiotics, synbiotics, fecal microbial transplantation (FMT), bioengineered bacteria, gut-restricted FXR agonists and others are promising therapeutic approaches that can alter gut microbiota composition to improve ALD. In the future, there will be new challenges to study the interactions between the genetics of individuals with ALD and their gut microbiome, to provide personalized interventions targeting the gut-liver axis, and to develop better techniques to measure microbial communities and metabolites in the body.
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Affiliation(s)
- Daya Zhang
- Graduate School, Hainan Medical University, Haikou, People’s Republic of China
| | - ZhengJin Liu
- Department of Gastroenterology, The Second Affiliated Hospital of Hainan Medical University, Haikou, People’s Republic of China
| | - Feihu Bai
- Department of Gastroenterology, The Second Affiliated Hospital of Hainan Medical University, Haikou, People’s Republic of China
- The Gastroenterology Clinical Medical Center of Hainan Province, Haikou, People’s Republic of China
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Wang Z, Luo C, Zhou EW, Sandhu AF, Yuan X, Williams GE, Cheng J, Sinha B, Akbar M, Bhattacharya P, Zhou S, Song BJ, Wang X. Molecular Toxicology and Pathophysiology of Comorbid Alcohol Use Disorder and Post-Traumatic Stress Disorder Associated with Traumatic Brain Injury. Int J Mol Sci 2023; 24:ijms24108805. [PMID: 37240148 DOI: 10.3390/ijms24108805] [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: 02/28/2023] [Revised: 05/05/2023] [Accepted: 05/08/2023] [Indexed: 05/28/2023] Open
Abstract
The increasing comorbidity of alcohol use disorder (AUD) and post-traumatic stress disorder (PTSD) associated with traumatic brain injury (TBI) is a serious medical, economic, and social issue. However, the molecular toxicology and pathophysiological mechanisms of comorbid AUD and PTSD are not well understood and the identification of the comorbidity state markers is significantly challenging. This review summarizes the main characteristics of comorbidity between AUD and PTSD (AUD/PTSD) and highlights the significance of a comprehensive understanding of the molecular toxicology and pathophysiological mechanisms of AUD/PTSD, particularly following TBI, with a focus on the role of metabolomics, inflammation, neuroendocrine, signal transduction pathways, and genetic regulation. Instead of a separate disease state, a comprehensive examination of comorbid AUD and PTSD is emphasized by considering additive and synergistic interactions between the two diseases. Finally, we propose several hypotheses of molecular mechanisms for AUD/PTSD and discuss potential future research directions that may provide new insights and translational application opportunities.
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Affiliation(s)
- Zufeng Wang
- Department of Neurosurgery, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
- Department of Forensic Medicine, Soochow University, Suzhou 215006, China
| | - Chengliang Luo
- Department of Neurosurgery, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
- Department of Forensic Medicine, Soochow University, Suzhou 215006, China
| | - Edward W Zhou
- Department of Neurosurgery, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Aaron F Sandhu
- Department of Neurosurgery, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Xiaojing Yuan
- Department of Neurosurgery, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - George E Williams
- Department of Neurosurgery, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Jialu Cheng
- Department of Neurosurgery, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Bharati Sinha
- Department of Neurosurgery, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Mohammed Akbar
- Division of Neuroscience & Behavior, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Rockville, MD 20892, USA
| | - Pallab Bhattacharya
- Department of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research (NIPER), Ahmedabad, Gandhinagar 382355, Gujarat, India
| | - Shuanhu Zhou
- Harvard Medical School, Harvard Stem Cell Institute, Boston, MA 02115, USA
| | - Byoung-Joon Song
- Section of Molecular Pharmacology and Toxicology, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Rockville, MD 20892, USA
| | - Xin Wang
- Department of Neurosurgery, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
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Hepatic, Extrahepatic and Extracellular Vesicle Cytochrome P450 2E1 in Alcohol and Acetaminophen-Mediated Adverse Interactions and Potential Treatment Options. Cells 2022; 11:cells11172620. [PMID: 36078027 PMCID: PMC9454765 DOI: 10.3390/cells11172620] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2022] [Revised: 08/03/2022] [Accepted: 08/19/2022] [Indexed: 12/15/2022] Open
Abstract
Alcohol and several therapeutic drugs, including acetaminophen, are metabolized by cytochrome P450 2E1 (CYP2E1) into toxic compounds. At low levels, these compounds are not detrimental, but higher sustained levels of these compounds can lead to life-long problems such as cytotoxicity, organ damage, and cancer. Furthermore, CYP2E1 can facilitate or enhance the effects of alcohol-drug and drug-drug interactions. In this review, we discuss the role of CYP2E1 in the metabolism of alcohol and drugs (with emphasis on acetaminophen), mediating injury/toxicities, and drug-drug/alcohol-drug interactions. Next, we discuss various compounds and various nutraceuticals that can reduce or prevent alcohol/drug-induced toxicity. Additionally, we highlight experimental outcomes of alcohol/drug-induced toxicity and potential treatment strategies. Finally, we cover the role and implications of extracellular vesicles (EVs) containing CYP2E1 in hepatic and extrahepatic cells and provide perspectives on the clinical relevance of EVs containing CYP2E1 in intracellular and intercellular communications leading to drug-drug and alcohol-drug interactions. Furthermore, we provide our perspectives on CYP2E1 as a druggable target using nutraceuticals and the use of EVs for targeted drug delivery in extrahepatic and hepatic cells, especially to treat cellular toxicity.
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10-Dehydrogingerdione ameliorates renal endoplasmic reticulum/oxidative stress and apoptosis in alcoholic nephropathy induced in experimental rats. Life Sci 2021; 279:119673. [PMID: 34081991 DOI: 10.1016/j.lfs.2021.119673] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2020] [Revised: 02/04/2021] [Accepted: 05/27/2021] [Indexed: 02/08/2023]
Abstract
BACKGROUND Chronic alcoholism induces kidney injury (KI), leading to increased mortality in alcoholic hepatitis patients. Endoplasmic reticulum stress (ER) represents the main initiator of kidney diseases and alcoholic nephropathy. AIMS We used alcoholic nephropathy rat model followed by 10-dehydrogingerdione (10-DHGD) intake as potential modulator. This is to focus on ER/oxidative stress/inflammatory and apoptotic pathways involvement. MAIN METHOD Alcoholic nephropathy was induced by alcohol administration (3.7 g/kg/body weight) orally and daily for 45 days. 10-DHGD (10 mg/kg/day) was administered either alone or along with alcohol. KEY FINDINGS Our results demonstrated significant increase in kidney function parameters like f creatinine, urea, uric acid, and blood urea nitrogen (BUN) levels. Renal ER/oxidative stress markers such as cytochrome P450 family two subfamily E member 1 (CYP2E1), C/EBP homologous protein (CHOP), and endoplasmic glucose-regulated protein 78 (GRP-78) demonstrated also significant increase. Inflammatory mediators like nuclear factor-kappa B (NF-kB), tumor necrosis factor-α (TNF-α), and transforming growth factor-β (TGF-β along with apoptotic marker caspase-3 behaved similarly. Antioxidant molecules like reduced glutathione (GSH), superoxide dismutase (SOD), and catalase demonstrated marked decrease. SIGNIFICANCE 10-DHGD administration resulted in significant modulation represented by an enhancement in the kidney functions and the histopathological patterns in a conclusion of its potential to ameliorate the pathological changes (kidney injury) induced by alcohol intake.
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Translational Approaches with Antioxidant Phytochemicals against Alcohol-Mediated Oxidative Stress, Gut Dysbiosis, Intestinal Barrier Dysfunction, and Fatty Liver Disease. Antioxidants (Basel) 2021; 10:antiox10030384. [PMID: 33806556 PMCID: PMC8000766 DOI: 10.3390/antiox10030384] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Revised: 02/25/2021] [Accepted: 02/25/2021] [Indexed: 12/12/2022] Open
Abstract
Emerging data demonstrate the important roles of altered gut microbiomes (dysbiosis) in many disease states in the peripheral tissues and the central nervous system. Gut dysbiosis with decreased ratios of Bacteroidetes/Firmicutes and other changes are reported to be caused by many disease states and various environmental factors, such as ethanol (e.g., alcohol drinking), Western-style high-fat diets, high fructose, etc. It is also caused by genetic factors, including genetic polymorphisms and epigenetic changes in different individuals. Gut dysbiosis, impaired intestinal barrier function, and elevated serum endotoxin levels can be observed in human patients and/or experimental rodent models exposed to these factors or with certain disease states. However, gut dysbiosis and leaky gut can be normalized through lifestyle alterations such as increased consumption of healthy diets with various fruits and vegetables containing many different kinds of antioxidant phytochemicals. In this review, we describe the mechanisms of gut dysbiosis, leaky gut, endotoxemia, and fatty liver disease with a specific focus on the alcohol-associated pathways. We also mention translational approaches by discussing the benefits of many antioxidant phytochemicals and/or their metabolites against alcohol-mediated oxidative stress, gut dysbiosis, intestinal barrier dysfunction, and fatty liver disease.
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Rungratanawanich W, Qu Y, Wang X, Essa MM, Song BJ. Advanced glycation end products (AGEs) and other adducts in aging-related diseases and alcohol-mediated tissue injury. Exp Mol Med 2021; 53:168-188. [PMID: 33568752 PMCID: PMC8080618 DOI: 10.1038/s12276-021-00561-7] [Citation(s) in RCA: 120] [Impact Index Per Article: 40.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2020] [Revised: 12/14/2020] [Accepted: 12/15/2020] [Indexed: 01/30/2023] Open
Abstract
Advanced glycation end products (AGEs) are potentially harmful and heterogeneous molecules derived from nonenzymatic glycation. The pathological implications of AGEs are ascribed to their ability to promote oxidative stress, inflammation, and apoptosis. Recent studies in basic and translational research have revealed the contributing roles of AGEs in the development and progression of various aging-related pathological conditions, such as diabetes, cardiovascular complications, gut microbiome-associated illnesses, liver or neurodegenerative diseases, and cancer. Excessive chronic and/or acute binge consumption of alcohol (ethanol), a widely consumed addictive substance, is known to cause more than 200 diseases, including alcohol use disorder (addiction), alcoholic liver disease, and brain damage. However, despite the considerable amount of research in this area, the underlying molecular mechanisms by which alcohol abuse causes cellular toxicity and organ damage remain to be further characterized. In this review, we first briefly describe the properties of AGEs: their formation, accumulation, and receptor interactions. We then focus on the causative functions of AGEs that impact various aging-related diseases. We also highlight the biological connection of AGE-alcohol-adduct formations to alcohol-mediated tissue injury. Finally, we describe the potential translational research opportunities for treatment of various AGE- and/or alcohol-related adduct-associated disorders according to the mechanistic insights presented.
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Affiliation(s)
- Wiramon Rungratanawanich
- grid.420085.b0000 0004 0481 4802Section of Molecular Pharmacology and Toxicology, Laboratory of Membrane Biochemistry and Biophysics, National Institute on Alcohol Abuse and Alcoholism, 9000 Rockville Pike, Bethesda, MD 20892 USA
| | - Ying Qu
- grid.420085.b0000 0004 0481 4802Section of Molecular Pharmacology and Toxicology, Laboratory of Membrane Biochemistry and Biophysics, National Institute on Alcohol Abuse and Alcoholism, 9000 Rockville Pike, Bethesda, MD 20892 USA
| | - Xin Wang
- Neuroapoptosis Drug Discovery Laboratory, Department of Neurosurgery, Brigham and Women’s Hospital, Harvard Medical School, 60 Fenwood Road, Boston, MA 02115 USA
| | - Musthafa Mohamed Essa
- grid.412846.d0000 0001 0726 9430Department of Food Science and Nutrition, Aging and Dementia Research Group, College of Agricultural and Marine Sciences, Sultan Qaboos University, Al-Khoud, Muscat, Oman ,grid.412846.d0000 0001 0726 9430Aging and Dementia Research Group, Sultan Qaboos University, Muscat, Oman
| | - Byoung-Joon Song
- grid.420085.b0000 0004 0481 4802Section of Molecular Pharmacology and Toxicology, Laboratory of Membrane Biochemistry and Biophysics, National Institute on Alcohol Abuse and Alcoholism, 9000 Rockville Pike, Bethesda, MD 20892 USA
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Cytochrome P450 CYP2E1 Suppression Ameliorates Cerebral Ischemia Reperfusion Injury. Antioxidants (Basel) 2021; 10:antiox10010052. [PMID: 33466250 PMCID: PMC7824747 DOI: 10.3390/antiox10010052] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Revised: 12/24/2020] [Accepted: 12/26/2020] [Indexed: 12/23/2022] Open
Abstract
Despite existing strong evidence on oxidative markers overproduction following ischemia/reperfusion (I/R), the mechanism by which oxidative enzyme Cytochrome P450-2E1 (CYP2E1) contributes to I/R outcomes is not clear. In this study, we sought to evaluate the functional significance of CYP2E1 in I/R. CYP2E1 KO mice and controls were subjected to middle cerebral artery occlusion (MCAo-90 min) followed by 24 h of reperfusion to induce focal I/R injury as an acute stage model. Then, histological and chemical analyses were conducted to investigate the role of CYP2E1 in lesion volume, oxidative stress, and inflammation exacerbation. Furthermore, the role of CYP2E1 on the blood-brain barrier (BBB) integrity was investigated by measuring 20-hydroxyecosatetraenoic acid (20-HETE) activity, as well as, in vivo BBB transfer rate. Following I/R, the CYP2E1 KO mice exhibited a significantly lower lesion volume, and neurological deficits compared to controls (p < 0.005). Moreover, reactive oxygen species (ROS) production, apoptosis, and neurodegeneration were significantly lower in the CYP2E1(−/−) I/R group (p < 0.001). The BBB damage was significantly lower in CYP2E1(−/−) mice compared to wild-type (WT) (p < 0.001), while 20-HETE production was increased by 41%. Besides, inflammatory cytokines expression and the number of activated microglia were significantly lower in CYP2E1(−/−) mice following I/R. CYP2E1 suppression ameliorates I/R injury and protects BBB integrity by reducing both oxidative stress and inflammation.
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Peng B, Yang Q, B Joshi R, Liu Y, Akbar M, Song BJ, Zhou S, Wang X. Role of Alcohol Drinking in Alzheimer's Disease, Parkinson's Disease, and Amyotrophic Lateral Sclerosis. Int J Mol Sci 2020; 21:ijms21072316. [PMID: 32230811 PMCID: PMC7177420 DOI: 10.3390/ijms21072316] [Citation(s) in RCA: 60] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Revised: 03/24/2020] [Accepted: 03/24/2020] [Indexed: 02/08/2023] Open
Abstract
Neurodegenerative diseases, including Alzheimer’s disease (AD), Parkinson’s disease (PD) and amyotrophic lateral sclerosis (ALS), increase as the population ages around the world. Environmental factors also play an important role in most cases. Alcohol consumption exists extensively and it acts as one of the environmental factors that promotes these neurodegenerative diseases. The brain is a major target for the actions of alcohol, and heavy alcohol consumption has long been associated with brain damage. Chronic alcohol intake leads to elevated glutamate-induced excitotoxicity, oxidative stress and permanent neuronal damage associated with malnutrition. The relationship and contributing mechanisms of alcohol with these three diseases are different. Epidemiological studies have reported a reduction in the prevalence of Alzheimer’s disease in individuals who drink low amounts of alcohol; low or moderate concentrations of ethanol protect against β-amyloid (Aβ) toxicity in hippocampal neurons; and excessive amounts of ethanol increase accumulation of Aβ and Tau phosphorylation. Alcohol has been suggested to be either protective of, or not associated with, PD. However, experimental animal studies indicate that chronic heavy alcohol consumption may have dopamine neurotoxic effects through the induction of Cytochrome P450 2E1 (CYP2E1) and an increase in the amount of α-Synuclein (αSYN) relevant to PD. The findings on the association between alcohol consumption and ALS are inconsistent; a recent population-based study suggests that alcohol drinking seems to not influence the risk of developing ALS. Additional research is needed to clarify the potential etiological involvement of alcohol intake in causing or resulting in major neurodegenerative diseases, which will eventually lead to potential therapeutics against these alcoholic neurodegenerative diseases.
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Affiliation(s)
- Bin Peng
- Departments of Neurosurgery, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Qiang Yang
- Hubei Provincial Key Lab for Quality and Safety of Traditional Chinese Medicine Health Food, Jing Brand Research Institute, Daye 435100, China
| | - Rachna B Joshi
- Departments of Neurosurgery, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, USA
- Internal Medicine, Stafford Medical, PA. 1364 NJ-72, Manahawkin, NJ 08050, USA
| | - Yuancai Liu
- Hubei Provincial Key Lab for Quality and Safety of Traditional Chinese Medicine Health Food, Jing Brand Research Institute, Daye 435100, China
| | - Mohammed Akbar
- Division of Neuroscience & Behavior, Laboratory of Membrane Biochemistry and Biophysics, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Rockville, MD 20852, 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, Rockville, MD 20892, USA;
| | - Shuanhu Zhou
- Departments of Orthopedic Surgery, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, USA
- Correspondence: (S.Z.); (X.W.); Tel.: 1-617-732-5398 (S.Z.); 1-617-732-4186 (X.W.)
| | - Xin Wang
- Departments of Neurosurgery, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, USA
- Correspondence: (S.Z.); (X.W.); Tel.: 1-617-732-5398 (S.Z.); 1-617-732-4186 (X.W.)
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Elkomy NMIM, Ibrahim IAAEH, El-Fayoumi HM, Elshazly SM. Effect of imidazoline-1 receptor agonists on renal dysfunction in rats associated with chronic, sequential fructose and ethanol administration. Clin Exp Pharmacol Physiol 2020; 47:609-619. [PMID: 31869439 DOI: 10.1111/1440-1681.13232] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2019] [Revised: 12/17/2019] [Accepted: 12/18/2019] [Indexed: 11/28/2022]
Abstract
Insulin resistance and chronic alcoholism are risk factors for renal dysfunction. This study investigated the therapeutic effects of two imidazoline-1 receptor (I1R) agonists on renal dysfunction in rats after chronic, sequential fructose and ethanol administration. Daily drinking water was supplemented with fructose (10%, w/v) for 12 weeks and then with ethanol (20%, v/v) for another 8 weeks. Rats were treated with rilmenidine and clonidine in the last two weeks of the study. Blood glucose and serum insulin (sIns) levels, lipid profiles, kidney function and renal histopathology were evaluated at the end of the experiment. Additionally, renal gene expression of nischarin, phosphatidylcholine-specific phospholipase C (PC-PLC) and prostaglandin E2 (PGE2) were measured. Renal levels of superoxide dismutase (SOD), malondialdehyde (MDA), myeloperoxidase (MPO), inducible nitric oxide synthase (iNOS) and total NO (tNO) were detected, and we determined the relative renal gene expression levels of alpha smooth muscle actin (α-SMA), hydroxyproline, interleukin 10 (IL-10), tumour necrosis factor alpha (TNF-α) and caspase-3. The results showed significant deterioration of blood glucose, sIns, lipid profiles, kidney function and renal histopathology in fructose/ethanol-fed rats. Additionally, markers of inflammation, fibrosis, apoptosis and oxidative stress were upregulated. The administration of rilmenidine or clonidine significantly improved blood glucose and sIns levels and reduced renal dysfunction. Our work showed that chronic, sequential fructose and ethanol administration induced fasting hyperglycaemia and renal impairment, and these effects were ameliorated by I1R agonists.
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Affiliation(s)
- Nesreen M I M Elkomy
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Zagazig University, Zagazig, Egypt
| | - Islam A A E-H Ibrahim
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Zagazig University, Zagazig, Egypt
| | - Hassan M El-Fayoumi
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Zagazig University, Zagazig, Egypt.,Department of Pharmacology and Toxicology, Faculty of Pharmacy, Kantara Sinai University, Arish, Egypt
| | - Shimaa M Elshazly
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Zagazig University, Zagazig, Egypt
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Kwon D, Kim SM, Correia MA. Cytochrome P450 endoplasmic reticulum-associated degradation (ERAD): therapeutic and pathophysiological implications. Acta Pharm Sin B 2020; 10:42-60. [PMID: 31993306 PMCID: PMC6976991 DOI: 10.1016/j.apsb.2019.11.002] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2019] [Revised: 10/30/2019] [Accepted: 10/31/2019] [Indexed: 02/07/2023] Open
Abstract
The hepatic endoplasmic reticulum (ER)-anchored cytochromes P450 (P450s) are mixed-function oxidases engaged in the biotransformation of physiologically relevant endobiotics as well as of myriad xenobiotics of therapeutic and environmental relevance. P450 ER-content and hence function is regulated by their coordinated hemoprotein syntheses and proteolytic turnover. Such P450 proteolytic turnover occurs through a process known as ER-associated degradation (ERAD) that involves ubiquitin-dependent proteasomal degradation (UPD) and/or autophagic-lysosomal degradation (ALD). Herein, on the basis of available literature reports and our own recent findings of in vitro as well as in vivo experimental studies, we discuss the therapeutic and pathophysiological implications of altered P450 ERAD and its plausible clinical relevance. We specifically (i) describe the P450 ERAD-machinery and how it may be repurposed for the generation of antigenic P450 peptides involved in P450 autoantibody pathogenesis in drug-induced acute hypersensitivity reactions and liver injury, or viral hepatitis; (ii) discuss the relevance of accelerated or disrupted P450-ERAD to the pharmacological and/or toxicological effects of clinically relevant P450 drug substrates; and (iii) detail the pathophysiological consequences of disrupted P450 ERAD, contributing to non-alcoholic fatty liver disease (NAFLD)/non-alcoholic steatohepatitis (NASH) under certain synergistic cellular conditions.
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Key Words
- 3MA, 3-methyladenine
- AAA, ATPases associated with various cellular activities
- ACC1, acetyl-CoA carboxylase 1
- ACC2, acetyl-CoA carboxylase 2
- ACHE, acetylcholinesterase
- ACOX1, acyl-CoA oxidase 1
- ALD, autophagic-lysosomal degradation
- AMPK1
- AP-1, activator protein 1
- ASK1, apoptosis signal-regulating kinase
- ATF2, activating transcription factor 2
- AdipoR1, gene of adiponectin receptor 1
- Atg14, autophagy-related 14
- CBZ, carbamazepine
- CHIP E3 ubiquitin ligase
- CHIP, carboxy-terminus of Hsc70-interacting protein
- Cytochromes P450
- Endoplasmic reticulum-associated degradation
- FOXO, forkhead box O
- Fas, fatty acid synthase
- GAPDH, glyceraldehyde 3-phosphate dehydrogenase
- INH, isoniazid
- IRS1, insulin receptor substrate 1
- Il-1β, interleukin 1 β
- Il-6, interleukin 6
- Insig1, insulin-induced gene 1
- JNK1
- Lpl, lipoprotein lipase
- Mcp1, chemokine (C–C motif) ligand 1
- Non-alcoholic fatty liver disease
- Non-alcoholic steatohepatitis
- Pgc1, peroxisome proliferator-activated receptor coactivator 1
- SREBP1c, sterol regulatory element binding transcription factor 1c
- Scd1, stearoyl-coenzyme A desaturase
- Tnf, tumor necrosis factor
- UPD, ubiquitin (Ub)-dependent proteasomal degradation
- Ub, ubiquitin
- gp78/AMFR E3 ubiquitin ligase
- gp78/AMFR, autocrine motility factor receptor
- shRNAi, shRNA interference
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Donohue TM, Osna NA, Kharbanda KK, Thomes PG. Lysosome and proteasome dysfunction in alcohol-induced liver injury. LIVER RESEARCH 2019. [DOI: 10.1016/j.livres.2019.11.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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Song BJ, Abdelmegeed MA, Cho YE, Akbar M, Rhim JS, Song MK, Hardwick JP. Contributing Roles of CYP2E1 and Other Cytochrome P450 Isoforms in Alcohol-Related Tissue Injury and Carcinogenesis. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1164:73-87. [PMID: 31576541 DOI: 10.1007/978-3-030-22254-3_6] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The purpose of this review is to briefly summarize the roles of alcohol (ethanol) and related compounds in promoting cancer and inflammatory injury in many tissues. Long-term chronic heavy alcohol exposure is known to increase the chances of inflammation, oxidative DNA damage, and cancer development in many organs. The rates of alcohol-mediated organ damage and cancer risks are significantly elevated in the presence of co-morbidity factors such as poor nutrition, unhealthy diets, smoking, infection with bacteria or viruses, and exposure to pro-carcinogens. Chronic ingestion of alcohol and its metabolite acetaldehyde may initiate and/or promote the development of cancer in the liver, oral cavity, esophagus, stomach, gastrointestinal tract, pancreas, prostate, and female breast. In this chapter, we summarize the important roles of ethanol/acetaldehyde in promoting inflammatory injury and carcinogenesis in several tissues. We also review the updated roles of the ethanol-inducible cytochrome P450-2E1 (CYP2E1) and other cytochrome P450 isozymes in the metabolism of various potentially toxic substrates, and consequent toxicities, including carcinogenesis in different tissues. We also briefly describe the potential implications of endogenous ethanol produced by gut bacteria, as frequently observed in the experimental models and patients of nonalcoholic fatty liver disease, in promoting DNA mutation and cancer development in the liver and other tissues, including the gastrointestinal tract.
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Affiliation(s)
- Byoung-Joon Song
- Section of Molecular Pharmacology and Toxicology, Laboratory of Membrane Biochemistry and Biophysics, National Institute on Alcohol Abuse and Alcoholism, NIH, Bethesda, MD, USA.
| | - Mohamed A Abdelmegeed
- Section of Molecular Pharmacology and Toxicology, Laboratory of Membrane Biochemistry and Biophysics, National Institute on Alcohol Abuse and Alcoholism, NIH, Bethesda, MD, USA
| | - Young-Eun Cho
- Section of Molecular Pharmacology and Toxicology, Laboratory of Membrane Biochemistry and Biophysics, National Institute on Alcohol Abuse and Alcoholism, NIH, Bethesda, MD, USA.,Department of Food Science and Nutrition, Andong National University, Andong, Republic of Korea
| | - Mohammed Akbar
- Division of Neuroscience and Behavior, National Institute on Alcohol Abuse and Alcoholism, NIH, Bethesda, MD, USA
| | - Johng S Rhim
- Department of Surgery, Uniformed Services University of the Health Sciences, Bethesda, MD, USA
| | - Min-Kyung Song
- Investigational Drug Branch, National Cancer Institute, NIH, Bethesda, MD, USA
| | - James P Hardwick
- Biochemistry and Molecular Pathology in the Department of Integrative Medical Sciences, Northeast Ohio Medical University, Rootstown, OH, USA
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Wang Y, Tang H, Xu M, Luo J, Zhao L, Shi F, Ye G, Lv C, Li Y. Effect of copper nanoparticles on brain cytochrome P450 enzymes in rats. Mol Med Rep 2019; 20:771-778. [PMID: 31180561 DOI: 10.3892/mmr.2019.10302] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2018] [Accepted: 03/28/2019] [Indexed: 11/06/2022] Open
Abstract
The aim of the present study was to evaluate the long‑term effect of copper nanoparticles (CuNPs) on cytochrome P450 (CYP450) enzymes in the rat brain. Rats were repeatedly gavaged with different forms of copper sources for 28 days, and the levels of oxidative stress and CYP450 mRNA and protein expression in the rat brain were subsequently analyzed. The results demonstrated that a high dose of CuNPs (200 mg/kg) induced severe oxidative stress in the rat brain along with a decrease in the levels of total superoxide dismutase and glutathione, and an increase in hydroxyl radicals and malondialdehyde. A medium dose of CuNPs reduced CYP450 2C11 and CYP450 3A1 protein expression in the rat brain, whereas high doses of CuNPs resulted in decreased expression of most CYP450 enzyme proteins, and inhibition of pregnane X receptor and constitutive androstane receptor expression. The results suggested that CuNPs may inhibit CYP450 enzyme expression by increasing the levels of oxidative stress and decreasing the expression of nuclear receptors in the rat brain, which affects the metabolism of drugs and endogenous hormones in the brain.
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Affiliation(s)
- Yanyan Wang
- Department of Pharmacy, School of Animal Medicine, Sichuan Agricultural University, Chengdu, Sichuan 611130, P.R. China
| | - Huaqiao Tang
- Department of Pharmacy, School of Animal Medicine, Sichuan Agricultural University, Chengdu, Sichuan 611130, P.R. China
| | - Min Xu
- Department of Pharmacy, School of Animal Medicine, Sichuan Agricultural University, Chengdu, Sichuan 611130, P.R. China
| | - Jie Luo
- Department of Pharmacy, School of Animal Medicine, Sichuan Agricultural University, Chengdu, Sichuan 611130, P.R. China
| | - Ling Zhao
- Department of Pharmacy, School of Animal Medicine, Sichuan Agricultural University, Chengdu, Sichuan 611130, P.R. China
| | - Fei Shi
- Department of Pharmacy, School of Animal Medicine, Sichuan Agricultural University, Chengdu, Sichuan 611130, P.R. China
| | - Gang Ye
- Department of Pharmacy, School of Animal Medicine, Sichuan Agricultural University, Chengdu, Sichuan 611130, P.R. China
| | - Cheng Lv
- Department of Pharmacy, School of Animal Medicine, Sichuan Agricultural University, Chengdu, Sichuan 611130, P.R. China
| | - Yinglun Li
- Department of Pharmacy, School of Animal Medicine, Sichuan Agricultural University, Chengdu, Sichuan 611130, P.R. China
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Cho YE, Song BJ. Pomegranate prevents binge alcohol-induced gut leakiness and hepatic inflammation by suppressing oxidative and nitrative stress. Redox Biol 2018; 18:266-278. [PMID: 30071471 PMCID: PMC6080577 DOI: 10.1016/j.redox.2018.07.012] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2018] [Revised: 06/28/2018] [Accepted: 07/19/2018] [Indexed: 01/13/2023] Open
Abstract
Alcoholic liver disease (ALD) is a major chronic liver disease worldwide and can range from simple steatosis, inflammation to fibrosis/cirrhosis possibly through leaky gut and systemic endotoxemia. We investigated whether pomegranate (POM) protects against binge alcohol-induced gut leakiness, endotoxemia, and inflammatory liver damage. After POM pretreatment for 10 days, rats were exposed to 3 oral doses of binge alcohol (5 g/kg/dose) or dextrose (as control) at 12-h intervals. Binge alcohol exposure induced leaky gut with significantly elevated plasma endotoxin and inflammatory fatty liver by increasing the levels of oxidative and nitrative stress marker proteins such as ethanol-inducible CYP2E1, inducible nitric oxide synthase, and nitrated proteins in the small intestine and liver. POM pretreatment significantly reduced the alcohol-induced gut barrier dysfunction, plasma endotoxin and inflammatory liver disease by inhibiting the elevated oxidative and nitrative stress marker proteins. POM pretreatment significantly restored the levels of intestinal tight junction (TJ) proteins such as ZO-1, occludin, claudin-1, and claundin-3 markedly diminished after alcohol-exposure. In addition, the levels of gut adherent junction (AJ) proteins (e.g., β-catenin and E-cadherin) and desmosome plakoglobin along with associated protein α-tubulin were clearly decreased in binge alcohol-exposed rats but restored to basal levels in POM-pretreated rats. Immunoprecipitation followed by immunoblot analyses revealed that intestinal claudin-1 protein was nitrated and ubiquitinated in alcohol-exposed rats, whereas these modifications were significantly blocked by POM pretreatment. These results showed for the first time that POM can prevent alcohol-induced gut leakiness and inflammatory liver injury by suppressing oxidative and nitrative stress.
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Affiliation(s)
- Young-Eun Cho
- Section of Molecular Pharmacology and Toxicology, Laboratory of Membrane Biochemistry and Biophysics, National Institute on Alcohol Abuse and Alcoholism, NIH, 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, NIH, Bethesda, MD 20892, USA.
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18
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Filser JG, Klein D. A physiologically based toxicokinetic model for inhaled ethylene and ethylene oxide in mouse, rat, and human. Toxicol Lett 2018; 286:54-79. [DOI: 10.1016/j.toxlet.2017.07.896] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2017] [Revised: 07/20/2017] [Accepted: 07/25/2017] [Indexed: 01/18/2023]
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19
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The Role of CYP2E1 in the Drug Metabolism or Bioactivation in the Brain. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2017; 2017:4680732. [PMID: 28163821 PMCID: PMC5259652 DOI: 10.1155/2017/4680732] [Citation(s) in RCA: 55] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/15/2016] [Revised: 11/24/2016] [Accepted: 11/29/2016] [Indexed: 01/08/2023]
Abstract
Organisms have metabolic pathways that are responsible for removing toxic agents. We always associate the liver as the major organ responsible for detoxification of the body; however this process occurs in many tissues. In the same way, as in the liver, the brain expresses metabolic pathways associated with the elimination of xenobiotics. Besides the detoxifying role of CYP2E1 for compounds such as electrophilic agents, reactive oxygen species, free radical products, and the bioactivation of xenobiotics, CYP2E1 is also related in several diseases and pathophysiological conditions. In this review, we describe the presence of phase I monooxygenase CYP2E1 in regions of the brain. We also explore the conditions where protein, mRNA, and the activity of CYP2E1 are induced. Finally, we describe the relation of CYP2E1 in brain disorders, including the behavioral relations for alcohol consumption via CYP2E1 metabolism.
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20
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Hartman JH, Miller GP, Caro AA, Byrum SD, Orr LM, Mackintosh SG, Tackett AJ, MacMillan-Crow LA, Hallberg LM, Ameredes BT, Boysen G. 1,3-Butadiene-induced mitochondrial dysfunction is correlated with mitochondrial CYP2E1 activity in Collaborative Cross mice. Toxicology 2017; 378:114-124. [PMID: 28082109 DOI: 10.1016/j.tox.2017.01.005] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2016] [Revised: 12/16/2016] [Accepted: 01/04/2017] [Indexed: 01/04/2023]
Abstract
Cytochrome P450 2E1 (CYP2E1) metabolizes low molecular weight hydrophobic compounds, including 1,3-butadiene, which is converted by CYP2E1 to electrophilic epoxide metabolites that covalently modify cellular proteins and DNA. Previous CYP2E1 studies have mainly focused on the enzyme localized in the endoplasmic reticulum (erCYP2E1); however, active CYP2E1 has also been found in mitochondria (mtCYP2E1) and the distribution of CYP2E1 between organelles can influence an individual's response to exposure. Relatively few studies have focused on the contribution of mtCYP2E1 to activation of chemical toxicants. We hypothesized that CYP2E1 bioactivation of 1,3-butadiene within mitochondria adversely affects mitochondrial respiratory complexes I-IV. A population of Collaborative Cross mice was exposed to air (control) or 200ppm 1,3-butadiene. Subcellular fractions (mitochondria, DNA, and microsomes) were collected from frozen livers and CYP2E1 activity was measured in microsomes and mitochondria. Individual activities of mitochondrial respiratory complexes I-IV were measured using in vitro assays and purified mitochondrial fractions. In air- and 1,3-butadiene-exposed mouse samples, mtDNA copy numbers were assessed by RT-PCR, and mtDNA integrity was assessed through a PCR-based assay. No significant changes in mtDNA copy number or integrity were observed; however, there was a decrease in overall activity of mitochondrial respiratory complexes I, II, and IV after 1,3-butadiene exposure. Additionally, higher mtCYP2E1 (but not erCYP2E1) activity was correlated with decreased mitochondrial respiratory complex activity (in complexes I-IV) in the 1,3-butadiene-exposed (not control) animals. Together, these results represent the first in vivo link between mitochondrial CYP2E1 activity and mitochondrial toxicity.
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Affiliation(s)
- Jessica H Hartman
- Department of Biochemistry and Molecular Biology, University of Arkansas for Medical Sciences, Little Rock, AR, United States
| | - Grover P Miller
- Department of Biochemistry and Molecular Biology, University of Arkansas for Medical Sciences, Little Rock, AR, United States.
| | - Andres A Caro
- Department of Chemistry, Hendrix College, Conway, AR, United States
| | - Stephanie D Byrum
- Department of Biochemistry and Molecular Biology, University of Arkansas for Medical Sciences, Little Rock, AR, United States
| | - Lisa M Orr
- Department of Biochemistry and Molecular Biology, University of Arkansas for Medical Sciences, Little Rock, AR, United States
| | - Samuel G Mackintosh
- Department of Biochemistry and Molecular Biology, University of Arkansas for Medical Sciences, Little Rock, AR, United States
| | - Alan J Tackett
- Department of Biochemistry and Molecular Biology, University of Arkansas for Medical Sciences, Little Rock, AR, United States
| | - Lee Ann MacMillan-Crow
- Pharmacology and Toxicology, University of Arkansas for Medical Sciences, Little Rock, AR, United States
| | - Lance M Hallberg
- Department of Preventive Medicine and Community Health, University of Texas Medical Branch, Galveston, TX, United States; Sealy Center for Environmental Health and Medicine, University of Texas Medical Branch, Galveston, TX, United States
| | - Bill T Ameredes
- Sealy Center for Environmental Health and Medicine, University of Texas Medical Branch, Galveston, TX, United States; Division of Pulmonary, Critical Care, and Sleep Medicine, and Department of Pharmacology and Toxicology, United States
| | - Gunnar Boysen
- Department of Environmental and Occupational Health, University of Arkansas for Medical Sciences, Little Rock, AR, United States; The Winthrop P. Rockefeller Cancer Institute, University of Arkansas for Medical Sciences, Little Rock, AR, United States.
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Daiker DH, Ward JB, Schoenfeld HA, Witz G, Moslen MT. Characterization of a Dietary Ethanol Protocol for Cyp2e1 Induction in the CD-1 Mouse without Evident Hepatic Toxicity or Genotoxicity. Int J Toxicol 2016. [DOI: 10.1080/109158199225242] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
Although the CD-1 mouse strain has been used to investigate the toxicity of numerous substrates of Cyp2e1, limited information is available about responses of this strain to ethanol, a potent and clinically relevant inducer of this cytochrome P450 isozyme. Our goal was to characterize a dietary ethanol protocol for greater than threefold induction of hepatic Cyp2e1 in CD-1 mice without confounding alterations to other biotransformation enzymes or injury to known target tissues. Female CD-1 mice were fed the Lieber-DeCarli liquid diet containing 1.4 to 6.4% ethanol (v/v) for time periods of 1 to 12 weeks. A series of range-finding experiments indicated that the stock 6.4% ethanol diet caused rapid weight loss, whereas dietary ethanol concentrations less than or equal to 3.2% produced inadequate (i.e., less than threefold) induction of hepatic Cyp2e1. Suitable responses were observed in mice fed a 4.1% ethanol diet, namely, body weight gain equivalent to both pair-fed or rodent chow control groups plus consistent and stable induction of hepatic Cyp2e1 activities by greater than threefold without evidence of hepatic lipid peroxidation or histopathology. Evaluations of other representative biotransformation activities, including bone marrow quinone reductase and hepatic aldehyde dehydrogenase, showed no alterations with the 4.1% ethanol diet, except for a modest 20% decline in hepatic glutathione peroxidase. Unlike observations in other species, Cyp2e1 induction was not evident in bone marrow or spleen by Western blot. Mice given the 4.1% ethanol diet for 6 and/or 12 weeks showed no changes in cellularity of the spleen or bone marrow, frequency of hprt mutations in splenic lymphocytes, or percentage of DNA-protein crosslinks in bone marrow cells. These parameters were monitored because ethanol at high exposures is known to cause immunosuppression and mild genotoxicity. Female CD-1 mice fed a 4.1% ethanol liquid diet showed substantial (greater than threefold) induction of hepatic Cyp2e1 without confounding detrimental effects on the fiver, spleen, or bone marrow. Thus, this dietary ethanol protocol should be useful for future investigations of the role of Cyp2e1 induction on genotoxicity responses to Cyp2e1 substrates.
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Affiliation(s)
| | | | - Heidi A. Schoenfeld
- UMDNJ-Robert Wood Johnson Medical School, Rutgers University, Piscataway, New Jersey, USA
| | - Gisela Witz
- UMDNJ-Robert Wood Johnson Medical School, Rutgers University, Piscataway, New Jersey, USA
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Alcohol and the Intestine. Biomolecules 2015; 5:2573-88. [PMID: 26501334 PMCID: PMC4693248 DOI: 10.3390/biom5042573] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2015] [Revised: 09/24/2015] [Accepted: 10/05/2015] [Indexed: 02/07/2023] Open
Abstract
Alcohol abuse is a significant contributor to the global burden of disease and can lead to tissue damage and organ dysfunction in a subset of alcoholics. However, a subset of alcoholics without any of these predisposing factors can develop alcohol-mediated organ injury. The gastrointestinal tract (GI) could be an important source of inflammation in alcohol-mediated organ damage. The purpose of review was to evaluate mechanisms of alcohol-induced endotoxemia (including dysbiosis and gut leakiness), and highlight the predisposing factors for alcohol-induced dysbiosis and gut leakiness to endotoxins. Barriers, including immunologic, physical, and biochemical can regulate the passage of toxins into the portal and systemic circulation. In addition, a host of environmental interactions including those influenced by circadian rhythms can impact alcohol-induced organ pathology. There appears to be a role for therapeutic measures to mitigate alcohol-induced organ damage by normalizing intestinal dysbiosis and/or improving intestinal barrier integrity. Ultimately, the inflammatory process that drives progression into organ damage from alcohol appears to be multifactorial. Understanding the role of the intestine in the pathogenesis of alcoholic liver disease can pose further avenues for pathogenic and treatment approaches.
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Alcohol hangover induces mitochondrial dysfunction and free radical production in mouse cerebellum. Neuroscience 2015; 304:47-59. [PMID: 26192095 DOI: 10.1016/j.neuroscience.2015.07.012] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2015] [Revised: 07/02/2015] [Accepted: 07/02/2015] [Indexed: 11/23/2022]
Abstract
Alcohol hangover (AH) is defined as the temporary state after alcohol binge-like drinking, starting when ethanol (EtOH) is absent in plasma. Previous data indicate that AH induces mitochondrial dysfunction and free radical production in mouse brain cortex. The aim of this work was to study mitochondrial function and reactive oxygen species production in mouse cerebellum at the onset of AH. Male mice received a single i.p. injection of EtOH (3.8g/kg BW) or saline solution. Mitochondrial function was evaluated 6h after injection (AH onset). At the onset of AH, malate-glutamate and succinate-supported state 4 oxygen uptake was 2.3 and 1.9-fold increased leading to a reduction in respiratory control of 55% and 48% respectively, as compared with controls. Decreases of 38% and 16% were found in Complex I-III and IV activities. Complex II-III activity was not affected by AH. Mitochondrial membrane potential and mitochondrial permeability changes were evaluated by flow cytometry. Mitochondrial membrane potential and permeability were decreased by AH in cerebellum mitochondria. Together with this, AH induced a 25% increase in superoxide anion and a 92% increase in hydrogen peroxide production in cerebellum mitochondria. Related to nitric oxide (NO) metabolism, neuronal nitric oxide synthase (nNOS) protein expression was 52% decreased by the hangover condition compared with control group. No differences were found in cerebellum NO production between control and treated mice. The present work demonstrates that the physiopathological state of AH involves mitochondrial dysfunction in mouse cerebellum showing the long-lasting effects of acute EtOH exposure in the central nervous system.
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Song BJ, Akbar M, Jo I, Hardwick JP, Abdelmegeed MA. Translational Implications of the Alcohol-Metabolizing Enzymes, Including Cytochrome P450-2E1, in Alcoholic and Nonalcoholic Liver Disease. ADVANCES IN PHARMACOLOGY 2015; 74:303-72. [PMID: 26233911 DOI: 10.1016/bs.apha.2015.04.002] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Fat accumulation (hepatic steatosis) in alcoholic and nonalcoholic fatty liver disease is a potentially pathologic condition which can progress to steatohepatitis (inflammation), fibrosis, cirrhosis, and carcinogenesis. Many clinically used drugs or some alternative medicine compounds are also known to cause drug-induced liver injury, which can further lead to fulminant liver failure and acute deaths in extreme cases. During liver disease process, certain cytochromes P450 such as the ethanol-inducible cytochrome P450-2E1 (CYP2E1) and CYP4A isozymes can be induced and/or activated by alcohol and/or high-fat diets and pathophysiological conditions such as fasting, obesity, and diabetes. Activation of these P450 isozymes, involved in the metabolism of ethanol, fatty acids, and various drugs, can produce reactive oxygen/nitrogen species directly and/or indirectly, contributing to oxidative modifications of DNA/RNA, proteins and lipids. In addition, aldehyde dehydrogenases including the mitochondrial low Km aldehyde dehydrogenase-2 (ALDH2), responsible for the metabolism of acetaldehyde and lipid aldehydes, can be inactivated by various hepatotoxic agents. These highly reactive acetaldehyde and lipid peroxides, accumulated due to ALDH2 suppression, can interact with cellular macromolecules DNA/RNA, lipids, and proteins, leading to suppression of their normal function, contributing to DNA mutations, endoplasmic reticulum stress, mitochondrial dysfunction, steatosis, and cell death. In this chapter, we specifically review the roles of the alcohol-metabolizing enzymes including the alcohol dehydrogenase, ALDH2, CYP2E1, and other enzymes in promoting liver disease. We also discuss translational research opportunities with natural and/or synthetic antioxidants, which can prevent or delay the onset of inflammation and liver disease.
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Affiliation(s)
- Byoung-Joon Song
- Section of Molecular Pharmacology and Toxicology, Laboratory of Membrane Biochemistry and Biophysics, National Institute on Alcohol Abuse and Alcoholism, Bethesda, Maryland, USA.
| | - Mohammed Akbar
- Section of Molecular Pharmacology and Toxicology, Laboratory of Membrane Biochemistry and Biophysics, National Institute on Alcohol Abuse and Alcoholism, Bethesda, Maryland, USA
| | - Inho Jo
- Department of Molecular Medicine, Ewha Womans University School of Medicine, Seoul, South Korea
| | - James P Hardwick
- Biochemistry and Molecular Pathology in Department of Integrative Medical Sciences, Northeast Ohio Medical University, Rootstown, Ohio, USA
| | - Mohamed A Abdelmegeed
- Section of Molecular Pharmacology and Toxicology, Laboratory of Membrane Biochemistry and Biophysics, National Institute on Alcohol Abuse and Alcoholism, Bethesda, Maryland, USA
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Forsyth CB, Voigt RM, Burgess HJ, Swanson GR, Keshavarzian A. Circadian rhythms, alcohol and gut interactions. Alcohol 2015; 49:389-98. [PMID: 25499101 DOI: 10.1016/j.alcohol.2014.07.021] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2014] [Revised: 07/09/2014] [Accepted: 07/17/2014] [Indexed: 12/14/2022]
Abstract
The circadian clock establishes rhythms throughout the body with an approximately 24 hour period that affect expression of hundreds of genes. Epidemiological data reveal chronic circadian misalignment, common in our society, significantly increases the risk for a myriad of diseases, including cardiovascular disease, diabetes, cancer, infertility and gastrointestinal disease. Disruption of intestinal barrier function, also known as gut leakiness, is especially important in alcoholic liver disease (ALD). Several studies have shown that alcohol causes ALD in only a 20-30% subset of alcoholics. Thus, a better understanding is needed of why only a subset of alcoholics develops ALD. Compelling evidence shows that increased gut leakiness to microbial products and especially LPS play a critical role in the pathogenesis of ALD. Clock and other circadian clock genes have been shown to regulate lipid transport, motility and other gut functions. We hypothesized that one possible mechanism for alcohol-induced intestinal hyperpermeability is through disruption of central or peripheral (intestinal) circadian regulation. In support of this hypothesis, our recent data shows that disruption of circadian rhythms makes the gut more susceptible to injury. Our in vitro data show that alcohol stimulates increased Clock and Per2 circadian clock proteins and that siRNA knockdown of these proteins prevents alcohol-induced permeability. We also show that intestinal Cyp2e1-mediated oxidative stress is required for alcohol-induced upregulation of Clock and Per2 and intestinal hyperpermeability. Our mouse model of chronic alcohol feeding shows that circadian disruption through genetics (in Clock(▵19) mice) or environmental disruption by weekly 12h phase shifting results in gut leakiness alone and exacerbates alcohol-induced gut leakiness and liver pathology. Our data in human alcoholics show they exhibit abnormal melatonin profiles characteristic of circadian disruption. Taken together our data support circadian mechanisms for alcohol-induced gut leakiness that could provide new therapeutic targets for ALD.
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Affiliation(s)
- Christopher B Forsyth
- Department of Internal Medicine, Division of Digestive Diseases and Nutrition, Rush University Medical Center, Chicago, IL, USA; Department of Biochemistry, Rush University Medical Center, Chicago, IL, USA.
| | - Robin M Voigt
- Department of Internal Medicine, Division of Digestive Diseases and Nutrition, Rush University Medical Center, Chicago, IL, USA
| | - Helen J Burgess
- Department of Behavioral Sciences, Rush University Medical Center, Chicago, IL USA
| | - Garth R Swanson
- Department of Internal Medicine, Division of Digestive Diseases and Nutrition, Rush University Medical Center, Chicago, IL, USA
| | - Ali Keshavarzian
- Department of Internal Medicine, Division of Digestive Diseases and Nutrition, Rush University Medical Center, Chicago, IL, USA; Department of Pharmacology, Rush University Medical Center, Chicago, IL, USA; Department of Molecular Biophysics & Physiology, Rush University Medical Center, Chicago, IL, USA; Division of Pharmacology, Utrecht Institute for Pharmaceutical Sciences, Faculty of Science, Utrecht University, Utrecht, The Netherlands
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Toselli F, Booth Depaz IM, Worrall S, Etheridge N, Dodd PR, Wilce PA, Gillam EMJ. Expression of CYP2E1 and CYP2U1 Proteins in Amygdala and Prefrontal Cortex: Influence of Alcoholism and Smoking. Alcohol Clin Exp Res 2015; 39:790-7. [DOI: 10.1111/acer.12697] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2014] [Accepted: 02/03/2015] [Indexed: 12/15/2022]
Affiliation(s)
- Francesca Toselli
- School of Chemistry and Molecular Biosciences; The University of Queensland, St. Lucia; Brisbane Queensland Australia
| | - Iris M. Booth Depaz
- School of Biomedical Sciences; The University of Queensland, St. Lucia; Brisbane Queensland Australia
| | - Simon Worrall
- School of Chemistry and Molecular Biosciences; The University of Queensland, St. Lucia; Brisbane Queensland Australia
| | - Naomi Etheridge
- School of Chemistry and Molecular Biosciences; The University of Queensland, St. Lucia; Brisbane Queensland Australia
| | - Peter R. Dodd
- School of Chemistry and Molecular Biosciences; The University of Queensland, St. Lucia; Brisbane Queensland Australia
| | - Peter A. Wilce
- School of Chemistry and Molecular Biosciences; The University of Queensland, St. Lucia; Brisbane Queensland Australia
| | - Elizabeth M. J. Gillam
- School of Chemistry and Molecular Biosciences; The University of Queensland, St. Lucia; Brisbane Queensland Australia
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Yun JW, Son MJ, Abdelmegeed MA, Banerjee A, Morgan TR, Yoo SH, Song BJ. Binge alcohol promotes hypoxic liver injury through a CYP2E1-HIF-1α-dependent apoptosis pathway in mice and humans. Free Radic Biol Med 2014; 77:183-94. [PMID: 25236742 PMCID: PMC4304203 DOI: 10.1016/j.freeradbiomed.2014.08.030] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/24/2014] [Revised: 08/27/2014] [Accepted: 08/28/2014] [Indexed: 12/11/2022]
Abstract
Binge drinking, a common pattern of alcohol ingestion, is known to potentiate liver injury caused by chronic alcohol abuse. This study was aimed at investigating the effects of acute binge alcohol on hypoxia-inducible factor-1α (HIF-1α)-mediated liver injury and the roles of alcohol-metabolizing enzymes in alcohol-induced hypoxia and hepatotoxicity. Mice and human specimens assigned to binge or nonbinge groups were analyzed for blood alcohol concentration (BAC), alcohol-metabolizing enzymes, HIF-1α-related protein nitration, and apoptosis. Binge alcohol promoted acute liver injury in mice with elevated levels of ethanol-inducible cytochrome P450 2E1 (CYP2E1) and hypoxia, both of which were colocalized in the centrilobular areas. We observed positive correlations among elevated BAC, CYP2E1, and HIF-1α in mice and humans exposed to binge alcohol. The CYP2E1 protein levels (r = 0.629, p = 0.001) and activity (r = 0.641, p = 0.001) showed a significantly positive correlation with BAC in human livers. HIF-1α levels were also positively correlated with BAC (r = 0.745, p < 0.001) or CYP2E1 activity (r = 0.792, p < 0.001) in humans. Binge alcohol promoted protein nitration and apoptosis with significant correlations observed between inducible nitric oxide synthase and BAC, CYP2E1, or HIF-1α in human specimens. Binge-alcohol-induced HIF-1α activation and subsequent protein nitration or apoptosis seen in wild type were significantly alleviated in the corresponding Cyp2e1-null mice, whereas pretreatment with an HIF-1α inhibitor, PX-478, prevented HIF-1α elevation with a trend of decreased levels of 3-nitrotyrosine and apoptosis, supporting the roles of CYP2E1 and HIF-1α in binge-alcohol-mediated protein nitration and hepatotoxicity. Thus binge alcohol promotes acute liver injury in mice and humans at least partly through a CYP2E1-HIF-1α-dependent apoptosis pathway.
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Affiliation(s)
- Jun-Won Yun
- Laboratory of Membrane Biochemistry and Biophysics, National Institute on Alcohol Abuse and Alcoholism, Bethesda, MD 20892-9410, USA
| | - Min-Jeong Son
- Institute of Forensic Medicine, Seoul National University College of Medicine, Seoul, South Korea
| | - Mohamed A Abdelmegeed
- Laboratory of Membrane Biochemistry and Biophysics, National Institute on Alcohol Abuse and Alcoholism, Bethesda, MD 20892-9410, USA
| | - Atrayee Banerjee
- Laboratory of Membrane Biochemistry and Biophysics, National Institute on Alcohol Abuse and Alcoholism, Bethesda, MD 20892-9410, USA
| | - Timothy R Morgan
- Gastroenterology Service, Veterans Administration Long Beach Healthcare System, Long Beach, CA 90822, USA; Division of Gastroenterology, University of California at Irvine, Irvine, CA 92697, USA
| | - Seong-Ho Yoo
- Institute of Forensic Medicine, Seoul National University College of Medicine, Seoul, South Korea.
| | - Byoung-Joon Song
- Laboratory of Membrane Biochemistry and Biophysics, National Institute on Alcohol Abuse and Alcoholism, Bethesda, MD 20892-9410, USA.
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Intestinal CYP2E1: A mediator of alcohol-induced gut leakiness. Redox Biol 2014; 3:40-6. [PMID: 25462064 PMCID: PMC4297927 DOI: 10.1016/j.redox.2014.10.002] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2014] [Revised: 10/13/2014] [Accepted: 10/15/2014] [Indexed: 02/07/2023] Open
Abstract
Chronic alcohol use can result in many pathological effects including alcoholic liver disease (ALD). While alcohol is necessary for the development of ALD, only 20-30% of alcoholics develop alcoholic steatohepatitis (ASH) with progressive liver disease leading to cirrhosis and liver failure (ALD). This suggests that while chronic alcohol consumption is necessary it is not sufficient to induce clinically relevant liver damage in the absence of a secondary risk factor. Studies in rodent models and alcoholic patients show that increased intestinal permeability to microbial products like endotoxin play a critical role in promoting liver inflammation in ALD pathogenesis. Therefore identifying mechanisms of alcohol-induced intestinal permeability is important in identifying mechanisms of ALD and for designing new avenues for therapy. Cyp2e1 is a cytochrome P450 enzyme that metabolizes alcohol has been shown to be upregulated by chronic alcohol use and to be a major source of oxidative stress and liver injury in alcoholics and in animal and in vitro models of chronic alcohol use. Because Cyp2e1 is also expressed in the intestine and is upregulated by chronic alcohol use, we hypothesized it could play a role in alcohol-induced intestinal hyperpermeability. Our in vitro studies with intestinal Caco-2 cells and in mice fed alcohol showed that circadian clock proteins CLOCK and PER2 are required for alcohol-induced permeability. We also showed that alcohol increases Cyp2e1 protein and activity but not mRNA in Caco-2 cells and that an inhibitor of oxidative stress or siRNA knockdown of Cyp2e1 prevents the increase in CLOCK or PER2 proteins and prevents alcohol-induced hyperpermeability. With our collaborators we have also shown that Cyp2e1 knockout mice are resistant to alcohol-induced gut leakiness and liver inflammation. Taken together our data support a novel Cyp2e1-circadian clock protein mechanism for alcohol-induced gut leakiness that could provide new avenues for therapy of ALD.
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Abdelmegeed MA, Banerjee A, Jang S, Yoo SH, Yun JW, Gonzalez FJ, Keshavarzian A, Song BJ. CYP2E1 potentiates binge alcohol-induced gut leakiness, steatohepatitis, and apoptosis. Free Radic Biol Med 2013; 65:1238-1245. [PMID: 24064383 PMCID: PMC3859835 DOI: 10.1016/j.freeradbiomed.2013.09.009] [Citation(s) in RCA: 147] [Impact Index Per Article: 13.4] [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: 09/12/2013] [Accepted: 09/17/2013] [Indexed: 02/07/2023]
Abstract
Ethanol-inducible cytochrome P450 2E1 (CYP2E1) contributes to increased oxidative stress and steatosis in chronic alcohol-exposure models. However, its role in binge ethanol-induced gut leakiness and hepatic injury is unclear. This study was aimed at investigating the role of CYP2E1 in binge alcohol-induced gut leakiness and the mechanisms of steatohepatitis. Female wild-type (WT) and Cyp2e1-null mice were treated with three doses of binge ethanol (WT-EtOH or Cyp2e1-null-EtOH) (6g/kg oral gavage at 12-h intervals) or dextrose (negative control). Intestinal histology of only WT-EtOH exhibited epithelial alteration and blebbing of lamina propria, and liver histology obtained at 6h after the last ethanol dose showed elevated steatosis with scattered inflammatory foci. These were accompanied by increased levels of serum endotoxin, hepatic enterobacteria, and triglycerides. All these changes, including the intestinal histology and hepatic apoptosis, determined by TUNEL assay, were significantly reversed when WT-EtOH mice were treated with the specific inhibitor of CYP2E1 chlormethiazole and the antioxidant N-acetylcysteine, both of which suppressed oxidative markers including intestinal CYP2E1. WT-EtOH also exhibited elevated amounts of serum TNF-α, hepatic cytokines, CYP2E1, and lipid peroxidation, with decreased levels of mitochondrial superoxide dismutase and suppressed aldehyde dehydrogenase 2 activity. Increased hepatocyte apoptosis with elevated levels of proapoptotic proteins and decreased levels of active (phosphorylated) p-AKT, p-AMPK, and peroxisome proliferator-activated receptor-α, all of which are involved in fat metabolism and inflammation, were observed in WT-EtOH. These changes were significantly attenuated in the corresponding Cyp2e1-null-EtOH mice. These data indicate that both intestinal and hepatic CYP2E1 induced by binge alcohol seems critical in binge alcohol-mediated increased nitroxidative stress, gut leakage, and endotoxemia; altered fat metabolism; and inflammation contributing to hepatic apoptosis and steatohepatitis.
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Affiliation(s)
- Mohamed A Abdelmegeed
- Laboratory of Membrane Biochemistry and Biophysics, National Institute on Alcohol Abuse and Alcoholism, Bethesda, MD 20892-9410, USA
| | - Atrayee Banerjee
- Laboratory of Membrane Biochemistry and Biophysics, National Institute on Alcohol Abuse and Alcoholism, Bethesda, MD 20892-9410, USA
| | - Sehwan Jang
- Laboratory of Membrane Biochemistry and Biophysics, National Institute on Alcohol Abuse and Alcoholism, Bethesda, MD 20892-9410, USA
| | - Seong-Ho Yoo
- Department of Forensic Medicine, Seoul National University College of Medicine, Seoul, South Korea
| | - Jun-Won Yun
- Laboratory of Membrane Biochemistry and Biophysics, National Institute on Alcohol Abuse and Alcoholism, Bethesda, MD 20892-9410, USA
| | - Frank J Gonzalez
- Laboratory of Metabolism, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Ali Keshavarzian
- Division of Gastroenterology, Rush University Medical Center, Chicago, IL 60612, USA
| | - Byoung-Joon Song
- Laboratory of Membrane Biochemistry and Biophysics, National Institute on Alcohol Abuse and Alcoholism, Bethesda, MD 20892-9410, USA.
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Forsyth CB, Voigt RM, Shaikh M, Tang Y, Cederbaum AI, Turek FW, Keshavarzian A. Role for intestinal CYP2E1 in alcohol-induced circadian gene-mediated intestinal hyperpermeability. Am J Physiol Gastrointest Liver Physiol 2013; 305:G185-95. [PMID: 23660503 PMCID: PMC3725682 DOI: 10.1152/ajpgi.00354.2012] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
We have shown that alcohol increases Caco-2 intestinal epithelial cell monolayer permeability in vitro by inducing the expression of redox-sensitive circadian clock proteins CLOCK and PER2 and that these proteins are necessary for alcohol-induced hyperpermeability. We hypothesized that alcohol metabolism by intestinal Cytochrome P450 isoform 2E1 (CYP2E1) could alter circadian gene expression (Clock and Per2), resulting in alcohol-induced hyperpermeability. In vitro Caco-2 intestinal epithelial cells were exposed to alcohol, and CYP2E1 protein, activity, and mRNA were measured. CYP2E1 expression was knocked down via siRNA and alcohol-induced hyperpermeability, and CLOCK and PER2 protein expression were measured. Caco-2 cells were also treated with alcohol or H₂O₂ with or without N-acetylcysteine (NAC) anti-oxidant, and CLOCK and PER2 proteins were measured at 4 or 2 h. In vivo Cyp2e1 protein and mRNA were also measured in colon tissue from alcohol-fed mice. Alcohol increased CYP2E1 protein by 93% and enzyme activity by 69% in intestinal cells in vitro. Alcohol feeding also increased mouse colonic Cyp2e1 protein by 73%. mRNA levels of Cyp2e1 were not changed by alcohol in vitro or in mouse intestine. siRNA knockdown of CYP2E1 in Caco-2 cells prevented alcohol-induced hyperpermeability and induction of CLOCK and PER2 proteins. Alcohol-induced and H₂O₂-induced increases in intestinal cell CLOCK and PER2 were significantly inhibited by treatment with NAC. We concluded that our data support a novel role for intestinal CYP2E1 in alcohol-induced intestinal hyperpermeability via a mechanism involving CYP2E1-dependent induction of oxidative stress and upregulation of circadian clock proteins CLOCK and PER2.
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Affiliation(s)
- Christopher B. Forsyth
- Departments of 1Internal Medicine, Division of Digestive Diseases and Nutrition, ,2Biochemistry,
| | - Robin M. Voigt
- Departments of 1Internal Medicine, Division of Digestive Diseases and Nutrition,
| | - Maliha Shaikh
- Departments of 1Internal Medicine, Division of Digestive Diseases and Nutrition,
| | - Yueming Tang
- Departments of 1Internal Medicine, Division of Digestive Diseases and Nutrition,
| | - Arthur I. Cederbaum
- 3Mount Sinai School of Medicine, Department of Pharmacology and System Therapeutics, New York, New York;
| | - Fred W. Turek
- 8Northwestern University Feinberg School of Medicine, Chicago; ,4Center for Sleep and Circadian Biology, Department of Neurobiology, Northwestern University, Evanston, Illinois;
| | - Ali Keshavarzian
- Departments of 1Internal Medicine, Division of Digestive Diseases and Nutrition, ,5Pharmacology, and ,6Molecular Biophysics and Physiology, Rush University Medical Center, Chicago; ,7Division of Pharmacology, Utrecht Institute for Pharmaceutical Sciences, Faculty of Science, Utrecht University, Utrecht, The Netherlands
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31
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Graw JA, von Haefen C, Poyraz D, Möbius N, Sifringer M, Spies CD. Chronic alcohol consumption increases the expression of uncoupling protein-2 and -4 in the brain. Alcohol Clin Exp Res 2013; 37:1650-6. [PMID: 23800309 DOI: 10.1111/acer.12144] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2012] [Accepted: 03/07/2013] [Indexed: 01/07/2023]
Abstract
BACKGROUND Chronic alcohol consumption leads to oxidative stress in a variety of cells, especially in brain cells because they have a reduced oxidative metabolism of alcohol. Uncoupling proteins (UCPs) are anion channels of the inner mitochondrial membrane, which can decouple internal respiration. "Mild uncoupling" of the mitochondrial respiratory chain leads to a reduced production of free radicals (reactive oxygen species) and a reduction in oxidative cell stress. The extent to which chronic alcohol consumption regulates UCP-2 and -4 in the brain is still unknown. METHODS We examined the effects of a 12-week 5% alcohol diet in the brain of male Wistar rats (n = 34). Cerebral gene and protein expression of UCP-2, -4, as well as Bcl-2, and the release of cytochrome c out of the mitochondria were detected by real-time polymerase chain reaction and Western blot analysis. The percentage of degenerated cells was determined by Fluoro-Jade B staining of brain slices. RESULTS Brains of rats with a chronic alcohol diet showed an increased gene and protein expression of UCP-2 and -4. The expression of the antiapoptotic protein Bcl-2 in the brain of the alcohol-treated animals was decreased significantly, whereas cytochrome c release from mitochondria was increased. In addition increased neurodegeneration could be demonstrated in the alcohol-treated animals. CONCLUSIONS Chronic alcohol consumption leads to a cerebral induction of UCP-2 and -4 with a simultaneous decrease in the antiapoptotic protein Bcl-2, cytochrome c release from mitochondria and increased neurodegeneration. This study reveals a compensatory effect of UCP-2 and -4 in the brain during chronic alcohol consumption.
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Affiliation(s)
- Jan A Graw
- Department of Anesthesiology and Intensive Care Medicine, Campus Charité Mitte and Campus Virchow-Klinikum, Charité-Universitätsmedizin Berlin, Berlin, Germany
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Dey A. Cytochrome P450 2E1: its clinical aspects and a brief perspective on the current research scenario. Subcell Biochem 2013; 67:1-104. [PMID: 23400917 DOI: 10.1007/978-94-007-5881-0_1] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Research on Cytochrome P450 2E1 (CYP2E1), a key enzyme in alcohol metabolism has been very well documented in literature. Besides the involvement of CYP2E1 in alcohol metabolism as illustrated through the studies discussed in the chapter, recent studies have thrown light on several other aspects of CYP2E1 i.e. its extrahepatic expression, its involvement in several diseases and pathophysiological conditions; and CYP2E1 mediated carcinogenesis and modulation of drug efficacy. Studies involving these interesting facets of CYP2E1 have been discussed in the chapter focusing on the recent observations or ongoing studies illustrating the crucial role of CYP2E1 in disease development and drug metabolism.
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Affiliation(s)
- Aparajita Dey
- AU-KBC Research Centre, Anna University, MIT Campus, Chromepet, Chennai, Tamil Nadu, 600044, India,
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Induction of brain CYP2E1 by chronic ethanol treatment and related oxidative stress in hippocampus, cerebellum, and brainstem. Toxicology 2012; 302:275-84. [PMID: 22960445 DOI: 10.1016/j.tox.2012.08.009] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2012] [Revised: 08/02/2012] [Accepted: 08/23/2012] [Indexed: 11/24/2022]
Abstract
Ethanol is one of the most commonly abused substances, and oxidative stress is an important causative factor in ethanol-induced neurotoxicity. Cytochrome P450 2E1 (CYP2E1) is involved in ethanol metabolism in the brain. This study investigates the role of brain CYP2E1 in the susceptibility of certain brain regions to ethanol neurotoxicity. Male Wistar rats were intragastrically treated with ethanol (3.0 g/kg, 30 days). CYP2E1 protein, mRNA expression, and catalytic activity in various brain regions were respectively assessed by immunoblotting, quantitative quantum dot immunohistochemistry, real-time RT-PCR, and LC-MS. The generation of reactive oxygen species (ROS) was analyzed using a laser confocal scanning microscope. The hippocampus, cerebellum, and brainstem were selectively damaged after ethanol treatment, indicated by both lactate dehydrogenase (LDH) activity and histopathological analysis. Ethanol markedly increased the levels of CYP2E1 protein, mRNA expression, and activity in the hippocampus and cerebellum. CYP2E1 protein and activity were significantly increased by ethanol in the brainstem, with no change in mRNA expression. ROS levels induced by ethanol paralleled the enhanced CYP2E1 proteins in the hippocampus, granular layer and white matter of cerebellum as well as brainstem. Brain CYP2E1 activity was positively correlated with the damage to the hippocampus, cerebellum, and brainstem. These results suggest that the selective sensitivity of brain regions to ethanol neurodegeneration may be attributed to the regional and cellular-specific induction of CYP2E1 by ethanol. The inhibition of CYP2E1 levels may attenuate ethanol-induced oxidative stress via ROS generation.
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Cacace S, Plescia F, Barberi I, Cannizzaro C. Acetaldehyde oral self-administration: evidence from the operant-conflict paradigm. Alcohol Clin Exp Res 2012; 36:1278-87. [PMID: 22324727 DOI: 10.1111/j.1530-0277.2011.01725.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2011] [Accepted: 11/21/2011] [Indexed: 11/29/2022]
Abstract
BACKGROUND Acetaldehyde (ACD), ethanol's first metabolite, has been reported to interact with the dopaminergic reward system, and with the neural circuits involved in stress response. Rats self-administer ACD directly into cerebral ventricles, and multiple intracerebroventricular infusions of ACD produce conditioned place preference. Self-administration has been largely employed to assess the reinforcing and addictive properties of most drugs of abuse. In particular, operant conditioning is a valid model to investigate drug-seeking and drug-taking behavior in rats. METHODS This study was aimed at the evaluation of (i) the motivational properties of oral ACD in the induction and maintenance of an operant-drinking behavior; (ii) ACD effect in a conflict situation employing the punishment-based Geller-Seifter procedure; and (iii) the onset of a relapse drinking behavior, following ACD deprivation. The lever-pressing procedure in a sound-attenuated operant-conditioning chamber was scheduled into 3 different periods: (i) training-rewarded responses with a fixed ratio 1; (ii) conflict-rewarded responses periodically associated with a 0.2 mA foot-shock; and (iii) relapse-rewarded lever presses following 1-week ACD abstinence. RESULTS Our results show that oral self-administrated ACD induced: a higher rate of punished responses in Geller-Seifter procedures; and the establishment of a relapse behavior following ACD deprivation. CONCLUSIONS In conclusion, our results indicate that ACD is able to induce an operant-drinking behavior, which is also maintained besides the conflict procedure and enhanced by the deprivation effect, supporting the hypothesis that ACD itself possesses motivational properties, such as alcohol and other substances of abuse.
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Affiliation(s)
- Silvana Cacace
- Department of Science for Health Promotion G. D'Alessandro, Section of Pharmacology, University of Palermo, Palermo, Italy
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35
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Ferguson CS, Tyndale RF. Cytochrome P450 enzymes in the brain: emerging evidence of biological significance. Trends Pharmacol Sci 2011; 32:708-14. [PMID: 21975165 DOI: 10.1016/j.tips.2011.08.005] [Citation(s) in RCA: 169] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2011] [Revised: 08/25/2011] [Accepted: 08/29/2011] [Indexed: 10/17/2022]
Abstract
Cytochrome P450 (CYP) enzymes are responsible for the metabolism of many exogenous and endogenous compounds. CYPs are abundant in the liver and are also expressed in many extra-hepatic tissues including the brain. Although total CYP levels in the brain are much lower than in the liver, brain CYPs are concentrated near drug targets in specific regions and cell types, and can potentially have a considerable impact on local metabolism. Individual differences in brain CYP metabolism, due to inducers, inhibitors or genetic variation, can influence sensitivity and response to centrally acting drugs. Brain CYPs may also play a role in modulating brain activity, behavior, susceptibility to central nervous system diseases and treatment outcomes. This review highlights recent progress that has been made in understanding the functional significance of CYPs in the brain.
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Affiliation(s)
- Charmaine S Ferguson
- Centre for Addiction and Mental Health and Departments of Psychiatry, Pharmacology and Toxicology, University of Toronto, 1 King's College Circle, Toronto, ON, Canada
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36
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Teplova VV, Belosludtsev KN, Belosludtseva NV, Holmuhamedov EL. Role of mitochondria in hepatotoxicity of ethanol. Biophysics (Nagoya-shi) 2010; 55:951-958. [DOI: 10.1134/s0006350910060114] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2023] Open
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37
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Yan Y, Yang JY, Mou YH, Wang LH, Zhang H, Wu CF. Possible Metabolic Pathways of Ethanol Responsible for Oxidative DNA Damage in Human Peripheral Lymphocytes. Alcohol Clin Exp Res 2010; 35:1-9. [DOI: 10.1111/j.1530-0277.2010.01316.x] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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38
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Cederbaum AI, Lu Y, Wu D. Role of oxidative stress in alcohol-induced liver injury. Arch Toxicol 2009; 83:519-48. [PMID: 19448996 DOI: 10.1007/s00204-009-0432-0] [Citation(s) in RCA: 426] [Impact Index Per Article: 28.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2009] [Accepted: 04/28/2009] [Indexed: 02/06/2023]
Abstract
Reactive oxygen species (ROS) are highly reactive molecules that are naturally generated in small amounts during the body's metabolic reactions and can react with and damage complex cellular molecules such as lipids, proteins, or DNA. Acute and chronic ethanol treatments increase the production of ROS, lower cellular antioxidant levels, and enhance oxidative stress in many tissues, especially the liver. Ethanol-induced oxidative stress plays a major role in the mechanisms by which ethanol produces liver injury. Many pathways play a key role in how ethanol induces oxidative stress. This review summarizes some of the leading pathways and discusses the evidence for their contribution to alcohol-induced liver injury. Special emphasis is placed on CYP2E1, which is induced by alcohol and is reactive in metabolizing and activating many hepatotoxins, including ethanol, to reactive products, and in generating ROS.
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Affiliation(s)
- Arthur I Cederbaum
- Department of Pharmacology and Systems Therapeutics, Mount Sinai School of Medicine, Box 1603, One Gustave L Levy Place, New York, NY 10029, USA.
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Hipólito L, Sánchez-Catalán MJ, Polache A, Granero L. Induction of brain CYP2E1 changes the effects of ethanol on dopamine release in nucleus accumbens shell. Drug Alcohol Depend 2009; 100:83-90. [PMID: 18990514 DOI: 10.1016/j.drugalcdep.2008.09.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/16/2008] [Revised: 09/08/2008] [Accepted: 09/12/2008] [Indexed: 01/05/2023]
Abstract
CYP2E1 is an important enzyme involved in the brain metabolism of ethanol that can be induced by chronic consumption of alcohol. Recent works have highlighted the importance of this system in the context of the behavioural effects of ethanol. Unfortunately, the underlying neurochemical events for these behavioural changes, has not been yet explored. In this work, we have started this exploration by analyzing the possible changes in the neurochemical response of the mesolimbic system to ethanol after pharmacological induction of brain CYP2E1. We have used the dopamine extracellular levels in nucleus accumbens (NAc) core and shell, measured by means of microdialysis in vivo, as an index of the effects of ethanol. Acetone 1% in the tap water was used to induce brain CYP2E1. Efficacy of the induction protocol was assessed by immunoblotting. Intravenous administration of 1.5 g/kg of ethanol in control rats provoked a significant increase of the dopamine levels in both the core (up to 127% of baseline) and the shell (up to 122% of baseline) of the NAc. However, the same dose of ethanol in acetone-treated rats only increased the dopamine extracellular levels in the core (up to 142% of baseline) whereas dopamine levels in the shell subregion remain unaltered relative to baseline. The results of this study indicate that induction of CYP2E1 changes the response of the mesolimbic system to ethanol in a region-dependent manner. Two hypotheses are postulated to explain the observed effects.
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Affiliation(s)
- Lucía Hipólito
- Departamento de Farmacia y Tecnología Farmacéutica, Universidad de Valencia, Avda Vicente Andrés Estellés s/n, 46100 Burjassot, Spain
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Abstract
Alcoholic fatty liver is a potentially pathologic condition which can progress to steatohepatitis, fibrosis, and cirrhosis if alcohol consumption is continued. Alcohol exposure may induce fatty liver by increasing NADH/NAD(+) ratio, increasing sterol regulatory element-binding protein-1 (SREBP-1) activity, decreasing peroxisome proliferator-activated receptor-alpha (PPAR-alpha) activity, and increasing complement C3 hepatic levels. Alcohol may increase SREBP-1 activity by decreasing the activities of AMP-activated protein kinase and sirtuin-1. Tumor necrosis factor-alpha (TNF-alpha) produced in response to alcohol exposure may cause fatty liver by up-regulating SREBP-1 activity, whereas betaine and pioglitazone may attenuate fatty liver by down-regulating SREBP-1 activity. PPAR-alpha agonists have potentials to attenuate alcoholic fatty liver. Adiponectin and interleukin-6 may attenuate alcoholic fatty liver by up-regulating PPAR-alpha and insulin signaling pathways while down-regulating SREBP-1 activity and suppressing TNF-alpha production. Recent studies show that paracrine activation of hepatic cannabinoid receptor 1 by hepatic stellate cell-derived endocannabinoids also contributes to the development of alcoholic fatty liver. Furthermore, oxidative modifications and inactivation of the enzymes involved in the mitochondrial and/or peroxisomal beta-oxidation of fatty acids could contribute to fat accumulation in the liver.
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Affiliation(s)
- Vishnudutt Purohit
- Division of Metabolism and Health Effects, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, 5635 Fishers Lane, Bethesda, MD 20892, USA.
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Reduction in the anxiolytic effects of ethanol by centrally formed acetaldehyde: the role of catalase inhibitors and acetaldehyde-sequestering agents. Psychopharmacology (Berl) 2008; 200:455-64. [PMID: 18587667 DOI: 10.1007/s00213-008-1219-3] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/04/2008] [Accepted: 05/28/2008] [Indexed: 12/30/2022]
Abstract
RATIONALE Considerable evidence indicates that brain ethanol metabolism mediated by catalase is involved in modulating some of the behavioral and physiological effects of this drug, which suggests that the first metabolite of ethanol, acetaldehyde, may have central actions. Previous results have shown that acetaldehyde administered into the lateral ventricles produced anxiolysis in a novel open arena in rats. OBJECTIVES The present studies investigate the effects of centrally formed acetaldehyde on ethanol-induced anxiolysis. MATERIALS AND METHODS The effects of the catalase inhibitor sodium azide (SA; 0 or 10 mg/kg, IP) on ethanol-induced anxiolysis (0.0, 0.5, or 1.0 g/kg, IP) were evaluated in CD1 mice in two anxiety paradigms, the elevated plus maze and the dark/light box. Additional studies assessed the effect of the noncompetitive catalase inhibitor 3-amino-1,2,4-triazole (AT; 0.5 g/kg, IP) and the acetaldehyde inactivation agent D: -penicillamine (50 mg/kg, IP) on the plus maze. RESULTS SA reduced the anxiolytic effects of ethanol on several parameters evaluated in the elevated plus maze and in the dark/light box. In the plus maze, AT completely blocked and D-penicillamine significantly reduced the anxiolytic properties of ethanol. CONCLUSIONS Thus, when cerebral metabolism of ethanol into acetaldehyde is blocked by catalase inhibitors, or acetaldehyde is inactivated, there is a suppressive effect on the anxiolytic actions of ethanol. These data provide further support for the idea that centrally formed or administered acetaldehyde can contribute to some of the psychopharmacological actions of ethanol, including its anxiolytic properties.
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Veeramachaneni S, Ausman LM, Choi SW, Russell RM, Wang XD. High dose lycopene supplementation increases hepatic cytochrome P4502E1 protein and inflammation in alcohol-fed rats. J Nutr 2008; 138:1329-35. [PMID: 18567756 PMCID: PMC2543121 DOI: 10.1093/jn/138.7.1329] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Recent in vitro evidence suggests that the antioxidant lycopene can prevent alcohol-induced oxidative stress and inflammation. However, knowledge of possible interactions in vivo between escalating doses of lycopene and chronic alcohol ingestion are lacking. In this study, we investigated potential interactions between alcohol ingestion and lycopene supplementation and their effect on hepatic lycopene concentration, cytochrome P4502E1 (CYP2E1) induction, and inflammation. Fischer 344 rats (6 groups, n = 10 per group) were fed either a liquid ethanol Lieber-DeCarli diet or a control diet (isocaloric maltodextrin substituted for ethanol) with or without lycopene supplementation at 2 doses (1.1 or 3.3 mg x kg body weight(-1) x d(-1)) for 11 wk. Plasma and hepatic concentrations of lycopene isomers were assessed by HPLC analysis. We examined expressions of hepatic CYP2E1 and tumor necrosis factor-alpha (TNFalpha) and the incidence of hepatic inflammatory foci. Both plasma and hepatic lycopene concentrations were greater in alcohol-fed rats than in control rats supplemented with identical doses of lycopene. In contrast, alcohol-fed rats had a lower percentage of lycopene cis isomers in the plasma and the liver compared with control rats fed the same dose of lycopene. Notably, lycopene supplementation at the higher dose significantly induced hepatic CYP2E1 protein, TNFalpha mRNA, and the incidence of inflammatory foci in the alcohol-fed rats but not in the control rats. These data indicate an interaction between chronic alcohol ingestion and lycopene supplementation and suggest a need for caution among individuals consuming high amounts of both alcohol and lycopene.
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Affiliation(s)
- Sudipta Veeramachaneni
- Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University, Boston, MA 02111
| | - Lynne M. Ausman
- Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University, Boston, MA 02111
| | - Sang Woon Choi
- Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University, Boston, MA 02111
| | - Robert M. Russell
- Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University, Boston, MA 02111
| | - Xiang-Dong Wang
- Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University, Boston, MA 02111
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Sánchez-Catalán MJ, Hipólito L, Guerri C, Granero L, Polache A. Distribution and differential induction of CYP2E1 by ethanol and acetone in the mesocorticolimbic system of rat. Alcohol Alcohol 2008; 43:401-7. [PMID: 18326880 DOI: 10.1093/alcalc/agn012] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
AIMS The expression of cytochrome P4502E1 (CYP2E1) in the brain has been demonstrated in several regions, nevertheless there is a lack of specific studies on the constitutive expression and induction at the mesocorticolimbic system, the most relevant brain pathway in the context of drug addiction and alcoholism. Hence, we have performed a detailed study of the CYP2E1 expression and induction in three key areas of the mesocorticolimbic system of the rat brain: prefrontal cortex (PFC), nucleus accumbens (NAc), and ventral tegmental area (VTA). METHODS Expression levels of CYP2E1 were analyzed by Western blot. The induction of the enzyme in the selected brain areas by chronic acetone (1% v/v acetone in drinking water for 11 days) and ethanol (3 g/kg by gavage for 7 days) was also assessed. RESULTS (i) CYP2E1 was expressed in PFC, Nac, and VTA, with the order of magnitude of the levels being VTA approximately PFC > Nac, and approximately 3-13% of it was encountered in liver; (ii) acetone treatment significantly increased CYP2E1 expression in Nac, up to 212% of the control levels, whereas not significant changes were observed in VTA and PFC; (iii) chronic ethanol treatment only resulted in a significant induction of enzyme levels in VTA (124%). A similar enhancement, though not significant, was found to occur in NAc. CONCLUSIONS CYP2E1 was present in the mesocorticolimbic system at different levels of expression. Chronic acetone and ethanol treatments are able to increase enzyme levels in specific areas of this system with the pattern of induction of the two agents being different.
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Affiliation(s)
- M José Sánchez-Catalán
- Departamento de Farmacia y Tecnología Farmacéutica, Universidad de Valencia, Avda Vicente Andrés Estellés s/n, 46100, Burjassot, Spain
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Lu Y, Cederbaum AI. CYP2E1 and oxidative liver injury by alcohol. Free Radic Biol Med 2008; 44:723-38. [PMID: 18078827 PMCID: PMC2268632 DOI: 10.1016/j.freeradbiomed.2007.11.004] [Citation(s) in RCA: 538] [Impact Index Per Article: 33.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/12/2007] [Revised: 11/02/2007] [Accepted: 11/05/2007] [Indexed: 12/11/2022]
Abstract
Ethanol-induced oxidative stress seems to play a major role in mechanisms by which ethanol causes liver injury. Many pathways have been suggested to contribute to the ability of ethanol to induce a state of oxidative stress. One central pathway seems to be the induction of cytochrome P450 2E1 (CYP2E1) by ethanol. CYP2E1 metabolizes and activates many toxicological substrates, including ethanol, to more reactive, toxic products. Levels of CYP2E1 are elevated under a variety of physiological and pathophysiological conditions and after acute and chronic alcohol treatment. CYP2E1 is also an effective generator of reactive oxygen species such as the superoxide anion radical and hydrogen peroxide and, in the presence of iron catalysts, produces powerful oxidants such as the hydroxyl radical. This review article summarizes some of the biochemical and toxicological properties of CYP2E1 and briefly describes the use of cell lines developed to constitutively express CYP2E1 and CYP2E1 knockout mice in assessing the actions of CYP2E1. Possible therapeutic implications for treatment of alcoholic liver injury by inhibition of CYP2E1 or CYP2E1-dependent oxidative stress will be discussed, followed by some future directions which may help us to understand the actions of CYP2E1 and its role in alcoholic liver injury.
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Affiliation(s)
- Yongke Lu
- Department of Pharmacology and Systems Therapeutics, Mount Sinai School of Medicine, New York, NY 10029, USA
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Wang H, Ping J, Peng RX, Yue J, Xia XY, Li QX, Kong R, Hong JY. Changes of multiple biotransformation phase I and phase II enzyme activities in human fetal adrenals during fetal development. Acta Pharmacol Sin 2008; 29:231-8. [PMID: 18215353 DOI: 10.1111/j.1745-7254.2008.00738.x] [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] [Indexed: 10/22/2022] Open
Abstract
AIM Fetal adrenal, which synthesizes steroid hormones, is critical to fetal growth and development. Our recent research showed that some xenobiotics could interfere with steroidogenesis and induce intrauterine growth retardation in rats. The study on the characteristics of biotransformation enzymes in fetal adrenals still seems to be important with respect to possible significance in xenobiotic-induced fetal development toxicity. In this study, the activities of several important xenobiotic-related phase I and phase II enzymes in human fetal adrenals were examined and compared with those in fetal livers. METHODS The activity and mRNA expression were determined by enzymatic analysis and RT-PCR. RESULTS The levels of cytochrome (CYP)2A6, CYP2E1, and CYP3A7 isozymes in fetal adrenals were 82%, 92%, and 33% of those in fetal livers, respectively. There was a good positive correlation between adrenal CYP2A6 activity and gestational time. The values of alpha glutathione S-transferase (GST), pi-GST, and microGST in adrenals were 0.5, 4.4, and 8.3-fold of those in the livers, respectively, and the activity of adrenal pi-GST was negatively correlated with gestational time. The uridine diphosphoglucuronyl transferase activities, which were measured using p-hydroxy-biphenyl and 7-hydroxy-4-methylcoumarin as substrates, were 9% and 3%, respectively, of those in the fetal livers. CONCLUSION Our investigation suggested that adrenal could be an important xenobiotic-metabolizing organ in fetal development and may play a potential role in xenobiotic-induced fetal development toxicity.
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Affiliation(s)
- Hui Wang
- Department of Pharmacology, Basic Medical School of Wuhan University, Wuhan 430071, China.
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Yoon M, Madden MC, Barton HA. Extrahepatic metabolism by CYP2E1 in PBPK modeling of lipophilic volatile organic chemicals: impacts on metabolic parameter estimation and prediction of dose metrics. JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH. PART A 2007; 70:1527-41. [PMID: 17710613 DOI: 10.1080/15287390701384684] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
Physiologically based pharmacokinetic (PBPK) models are increasingly available for environmental chemicals and applied in risk assessments. Volatile organic compounds (VOCs) are important pollutants in air, soil, and water. CYP2E1 metabolically activates many VOCs in animals and humans. Despite its presence in extrahepatic tissues, the metabolism by CYP2E1 is often described as restricted to the liver in PBPK models, unless target tissue dose metrics in extrahepatic tissues are needed for the model application, including risk assessment. The impact of accounting for extrahepatic metabolism by CYP2E1 on the estimation of metabolic parameters and the prediction of dose metrics was evaluated for three lipophilic VOCs: vinyl chloride, trichloroethylene, and carbon tetrachloride. Metabolic parameters estimated from fitting gas uptake data with and without extrahepatic metabolism were similar. The impact of extrahepatic metabolism on PBPK predictions was evaluated using inhalation exposure scenarios relevant for animal toxicity studies and human risk assessment. Although small, the relative role of extrahepatic metabolism and the differences in the predicted dose metrics were greater at low exposure concentrations. The impact was species dependent and influenced by Km for CYP2E1. The current study indicates that inhalation modeling for several representative VOCs that are CYP2E1 substrates is not affected by the inclusion of extrahepatic metabolism, implying that liver-only metabolism may be a reasonable simplification for PBPK modeling of lipophilic VOCs. The PBPK predictions using this assumption can be applied confidently for risk assessment, but this conclusion should not necessarily be applied to VOCs that are metabolized by other enzymes.
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Affiliation(s)
- Miyoung Yoon
- National Research Council Research Associateship Program, North Carolina, USA
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Donohue TM, Cederbaum AI, French SW, Barve S, Gao B, Osna NA. Role of the proteasome in ethanol-induced liver pathology. Alcohol Clin Exp Res 2007; 31:1446-59. [PMID: 17760783 DOI: 10.1111/j.1530-0277.2007.00454.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The ubiquitin-proteasome system has come to be known as a vital constituent of mammalian cells. The proteasome is a large nonlysosomal enzyme that acts in concert with an 8.5 kDa polypeptide called ubiquitin and a series of conjugating enzymes, known as E1, E2 and E3, that covalently bind multiple ubiquitin moieties in a polyubiquitin chain to protein substrates in a process called ubiquitylation. The latter process targets protein substrates for unfolding and degradation by the 26S proteasome. This enzyme system specifically recognizes and degrades polyubiquitylated proteins, many of which are key proteins involved in cell cycle regulation, apoptosis, signal transduction, and antigen presentation. The 26S proteasome contains a cylinder-shaped 20S catalytic core that, itself, degrades proteins in an ATP- and ubiquitin-independent manner. The 20S form is actually the predominant enzyme form in mammalian cells. Proteolysis by the constitutive 20S proteasome is vital in removing oxidized, misfolded and otherwise modified proteins. Such degradation is critical as a means of cellular detoxification, as intracellular accumulation of damaged and misfolded proteins is potentially lethal. Studies have shown that inhibition of proteasome activity can lead to cell death. Ethanol and its metabolism cause partial inhibition of the proteasome. This leads to a number of pleiotropic effects that can affect a variety of cellular processes. This critical review describes important aspects of ethanol metabolism and its influence on the proteasome. The review will summarize recent findings on: (1) the interactions between the proteasome and the ethanol metabolizing enzyme, CYP2E1; (2) the dynamics of proteasome inhibition by ethanol in animal models and cultured cells; (3) ethanol-elicited suppression of proteasome activity and its effect on signal transduction; (4) The role of proteasome inhibition in cytokine production by liver cells; and (5) ethanol elicited suppression of peptide hydrolysis and the potential effects on antigen presentation. While the principal focus is on alcohol-induced liver injury, the authors foresee that the findings presented in this review will prompt further research on the role of this proteolytic system in other tissues injured by excessive alcohol consumption.
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Affiliation(s)
- Terrence M Donohue
- Liver Study Unit, Omaha VA Medical Center, Department of Internal Medicine, University of Nebraska Medical Center, Omaha, Nebraska, USA.
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Yadav S, Dhawan A, Singh RL, Seth PK, Parmar D. Expression of constitutive and inducible cytochrome P450 2E1 in rat brain. Mol Cell Biochem 2006; 286:171-80. [PMID: 16652227 DOI: 10.1007/s11010-005-9109-z] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2005] [Accepted: 12/13/2005] [Indexed: 01/31/2023]
Abstract
Studies initiated to investigate the expression of cytochrome P450 2E1 (CYP2E1) in rat brain demonstrated low but detectable protein and mRNA expression in control rat brain. Though mRNA and protein expression of CYP2E1 in brain was several fold lower as compared to liver, relatively high activity of N-nitrosodimethylamine demethylase (NDMA-d) was observed in control rat brain microsomes. Like liver, pretreatment with CYP2E1 inducers such as ethanol or pyrazole or acetone significantly increased the activity of brain microsomal NDMA-d. Kinetic studies also showed an increase in the Vmax and affinity (Km) of the substrate towards the brain enzyme due to increased expression of CYP2E1 in microsomes of brain isolated from ethanol pretreated rats. In vitro studies using organic inhibitors, specific for CYP2E1 and anti-CYP2E1 significantly inhibited the brain NDMA-d activity indicating that like liver, NDMA-d activity in rat brain is catalyzed by CYP2E1. Olfactory lobes exhibited the highest CYP2E1 expression and catalytic activity in control rats. Furthermore, several fold increase in the mRNA expression and activity of CYP2E1 in cerebellum and hippocampus while a relatively small increase in the olfactory lobes and no significant change in other brain regions following ethanol pretreatment have indicated that CYP2E1 induction maybe involved in selective sensitivity of these brain areas to ethanol induced free radical damage and neuronal degeneration.
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Affiliation(s)
- Sanjay Yadav
- Industrial Toxicology Research Centre, P.O. Box 80, Mahatma Gandhi Marg, Lucknow 226 001, INDIA
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Kim BJ, Hood BL, Aragon RA, Hardwick JP, Conrads TP, Veenstra TD, Song BJ. Increased oxidation and degradation of cytosolic proteins in alcohol-exposed mouse liver and hepatoma cells. Proteomics 2006; 6:1250-60. [PMID: 16408314 PMCID: PMC1368983 DOI: 10.1002/pmic.200500447] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
We recently developed a sensitive method using biotin-N-maleimide (biotin-NM) as a probe to positively identify oxidized mitochondrial proteins. In this study, biotin-NM was used to identify oxidized cytosolic proteins in alcohol-fed mouse livers. Alcohol treatment for 6 wk elevated the levels of CYP2E1 and nitrotyrosine, a marker of oxidative stress. Markedly increased levels of oxidized proteins were detected in alcohol-fed mouse livers compared to pair-fed controls. The biotin-NM-labeled oxidized proteins from alcohol-exposed mouse livers were subsequently purified with streptavidin-agarose and resolved on 2-DE. More than 90 silver-stained protein spots that displayed differential intensities on 2-D gels were identified by MS. Peptide sequence analysis revealed that many enzymes or proteins involved in stress response, chaperone activity, intermediary metabolism, and antioxidant defense systems such as peroxiredoxin were oxidized after alcohol treatment. Smaller fragments of many proteins were repeatedly detected only in alcohol-fed mice, indicating that many oxidized proteins after alcohol exposure were degraded. Immunoblot results showed that the level of oxidized peroxiredoxin (inactivated) was markedly increased in the alcohol-exposed mouse livers and ethanol-sensitive hepatoma cells compared to the corresponding controls. Our results may explain the underlying mechanism for cellular dysfunction and increased susceptibility to other toxic agents following alcohol-mediated oxidative stress.
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Affiliation(s)
- Bong-Jo Kim
- Laboratory of Membrane Biochemistry and Biophysics, National Institute on Alcohol Abuse and Alcoholism, Bethesda, MD 20892-9410, USA
| | - Brian L. Hood
- Laboratory of Proteomics and Analytical Technologies, SAIC-Frederick, Inc., Frederick, MD, USA and
| | - Richard A. Aragon
- Laboratory of Membrane Biochemistry and Biophysics, National Institute on Alcohol Abuse and Alcoholism, Bethesda, MD 20892-9410, USA
| | - James P. Hardwick
- Department of Biochemistry, Northeastern Ohio University College of Medicine, Rootstown, OH, USA
| | - Thomas P. Conrads
- Laboratory of Proteomics and Analytical Technologies, SAIC-Frederick, Inc., Frederick, MD, USA and
| | - Timothy D. Veenstra
- Laboratory of Proteomics and Analytical Technologies, SAIC-Frederick, Inc., Frederick, MD, USA and
| | - Byoung J. Song
- Laboratory of Membrane Biochemistry and Biophysics, National Institute on Alcohol Abuse and Alcoholism, Bethesda, MD 20892-9410, USA
- To whom correspondence should be addressed: Dr. B. J. Song, Laboratory of Membrane Biochemistry and Biophysics, National Institute on Alcohol Abuse and Alcoholism, 9000 Rockville Pike, Bethesda, MD 20892-9410, USA. (e-mail); (Fax) 1-301-594-3113
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Hutchinson TH, Shillabeer N, Winter MJ, Pickford DB. Acute and chronic effects of carrier solvents in aquatic organisms: a critical review. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2006; 76:69-92. [PMID: 16290221 DOI: 10.1016/j.aquatox.2005.09.008] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2005] [Revised: 09/13/2005] [Accepted: 09/13/2005] [Indexed: 05/05/2023]
Abstract
Recognising the scientific and regulatory need for testing relatively hydrophobic or 'difficult substances', the OECD currently recommends that selected organic solvents may be used in aquatic toxicity testing in order to help achieve more effective dispersion of the toxicant. The OECD recommends a maximum solvent concentration of 100 microl l(-1) (with specific gravity equivalents to 100 microl l(-1) in parentheses) for acetone (79 mg l(-1)), dimethylformamide (95 mg l(-1)), dimethylsulfoxide (1.10 mg l(-1)), ethanol (78.9 mg l(-1)), methanol (79.2 mg l(-1)) and triethylene glycol (1.12 mg l(-1)). While this recommendation is supported by historical data, we have recently observed evidence that some solvents may affect the reproduction of certain fish species, and also impact biomarkers of endocrine disruption. This review presents available data on the effects of solvents in aquatic organisms, supplemented by relevant information from mammalian studies (e.g. effects on liver enzyme induction potentially altering the metabolism of sex hormones). In conclusion, it is recommended that maximum effort should be given to avoiding the use of carrier solvents wherever possible, for example through the use of saturation columns or other physical methods (e.g. stirring or ultrasonification). Where solvent use is necessary, however, it is recommended that in reproduction studies with aquatic organisms, the maximum solvent concentration should not exceed 20 microl l(-1) of dilution water.
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Affiliation(s)
- T H Hutchinson
- AstraZeneca Global Safety, Health and Environment, Brixham Environmental Laboratory, Freshwater Quarry, Brixham, Devon TQ5 8BA, UK.
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