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Firouzjaei AA, Aghaee-Bakhtiari SH, Tafti A, Sharifi K, Abadi MHJN, Rezaei S, Mohammadi-Yeganeh S. Impact of curcumin on ferroptosis-related genes in colorectal cancer: Insights from in-silico and in-vitro studies. Cell Biochem Funct 2023; 41:1488-1502. [PMID: 38014635 DOI: 10.1002/cbf.3889] [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: 05/15/2023] [Revised: 11/11/2023] [Accepted: 11/13/2023] [Indexed: 11/29/2023]
Abstract
Colorectal cancer (CRC) is responsible for a significant number of cancer-related fatalities worldwide. Researchers are investigating the therapeutic potential of ferroptosis, a type of iron-dependent controlled cell death, in the context of CRC. Curcumin, a natural compound found in turmeric, exhibits anticancer properties. This study explores the effects of curcumin on genes related to ferroptosis (FRGs) in CRC. To gather CRC data, we used the Gene Expression Profiling Interactive Analysis (GEPIA) and Gene Expression Omnibus (GEO) databases, while FRGs were obtained from the FerrDb database and PubMed. We identified 739 CRC differentially expressed genes (DEGs) in CRC and discovered 39 genes that were common genes between FRGs and CRC DEGs. The DEGs related to ferroptosis were enriched with various biological processes and molecular functions, including the regulation of signal transduction and glucose metabolism. Using the Drug Gene Interaction Database (DGIdb), we predicted drugs targeting CRC-DEGs and identified 17 potential drug targets. Additionally, we identified eight essential proteins related to ferroptosis in CRC, including MYC, IL1B, and SLC1A5. Survival analysis revealed that alterations in gene expression of CDC25A, DDR2, FABP4, IL1B, SNCA, and TFAM were associated with prognosis in CRC patients. In SW480 human CRC cells, treatment with curcumin decreased the expression of MYC, IL1B, and EZH2 mRNA, while simultaneously increasing the expression of SLCA5 and CAV1. The findings of this study suggest that curcumin could regulate FRGs in CRC and have the potential to be utilized as a therapeutic agent for treating CRC.
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Affiliation(s)
- Ali Ahmadizad Firouzjaei
- Department of Medical Biotechnology, School of Advanced Technologies in Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Seyed Hamid Aghaee-Bakhtiari
- Department of Medical Biotechnology and Nanotechnology, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
- Bioinformatics Research Group, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Ali Tafti
- Department of Biotechnology and Molecular Medicine, Faculty of Medicine, Arak University of Medical Sciences, Arak, Iran
| | - Kazem Sharifi
- Department of Medical Biotechnology, School of Advanced Technologies in Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | | | - Samaneh Rezaei
- Department of Medical Biotechnology and Nanotechnology, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Samira Mohammadi-Yeganeh
- Department of Medical Biotechnology, School of Advanced Technologies in Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
- Medical Nanothechnology and Tissue Engineering Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
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Blood Vessels as a Key Mediator for Ethanol Toxicity: Implication for Neuronal Damage. LIFE (BASEL, SWITZERLAND) 2022; 12:life12111882. [PMID: 36431016 PMCID: PMC9696276 DOI: 10.3390/life12111882] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/04/2022] [Revised: 11/10/2022] [Accepted: 11/10/2022] [Indexed: 11/16/2022]
Abstract
Excessive intake of ethanol is associated with severe brain dysfunction, and the subsequent neurological and behavioral abnormalities are well-established social risks. Many research studies have addressed how ethanol induces neurological toxicity. However, the underlying mechanisms with which ethanol induces neurological toxicity are still obscure, perhaps due to the variety and complexity of these mechanisms. Epithelial cells are in direct contact with blood and can thus mediate ethanol neurotoxicity. Ethanol activates the endothelial cells of blood vessels, as well as lymphatic vessels, in a concentration-dependent manner. Among various signaling mediators, nitric oxide plays important roles in response to ethanol. Endothelial and inducible nitric oxide synthases (eNOS and iNOS) are upregulated and activated by ethanol and enhance neuroinflammation. On the other hand, angiogenesis and blood vessel remodeling are both affected by ethanol intake, altering blood supply and releasing angiocrine factors to regulate neuronal functions. Thus, ethanol directly acts on endothelial cells, yet the molecular target(s) on endothelial cells remain unknown. Previous studies on neurons and glial cells have validated the potential contribution of membrane lipids and some specific proteins as ethanol targets, which may also be the case in endothelial cells. Future studies, based on current knowledge, will allow for a greater understanding of the contribution and underlying mechanisms of endothelial cells in ethanol-induced neurological toxicity, protecting neurological health against ethanol toxicity.
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Liang HW, Yang TY, Teng CS, Lee YJ, Yu MH, Lee HJ, Hsu LS, Wang CJ. Mulberry leaves extract ameliorates alcohol-induced liver damages through reduction of acetaldehyde toxicity and inhibition of apoptosis caused by oxidative stress signals. Int J Med Sci 2021; 18:53-64. [PMID: 33390773 PMCID: PMC7738976 DOI: 10.7150/ijms.50174] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Accepted: 10/13/2020] [Indexed: 02/06/2023] Open
Abstract
Mulberry leaves (Morus alba L.), which are traditional Chinese herbs, exert several biological functions, such as antioxidant, anti-inflammation, antidiabetic, and antitumor. Alcohol intake increases inflammation and oxidative stress, and this increase causes liver injury and leads to liver steatosis, cirrhosis, and hepatocellular carcinoma, which are major health problems worldwide. Previous report indicated that mulberry leaf extract (MLE) exited hepatoprotection effects against chronic alcohol-induced liver damages. In this present study, we investigated the effects of MLE on acute alcohol and liver injury induced by its metabolized compound called acetaldehyde (ACE) by using in vivo and in vitro models. Administration of MLE reversed acute alcohol-induced liver damages, increased acetaldehyde (ACE) level, and decreased aldehyde dehydrogenase activity in a dose-dependent manner. Acute alcohol exposure-induced leukocyte infiltration and pro-inflammation factors, including cyclooxygenase-2 (COX-2), tumor necrosis factor-α (TNF-α), and interleukin-6 (IL-6), were blocked by MLE in proportion to MLE concentration. MLE prevented alcohol-induced liver apoptosis via enhanced caveolin-1 expression and attenuated EGFR/STAT3/iNOS pathway using immunohistochemical analysis. ACE induced proteins, such as iNOS, COX-2, TNF-α, and IL-6, and inhibited superoxide dismutase expression, whereas co-treated with MLE reversed these proteins expression. MLE also recovered alcohol-induced apoptosis in cultured Hep G2 cells. Overall, our findings indicated that MLE ameliorated acute alcohol-induced liver damages by reducing ACE toxicity and inhibiting apoptosis caused by oxidative stress signals. Our results implied that MLE might be a potential agent for treating alcohol liver disease.
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Affiliation(s)
- Hsin-Wen Liang
- Institute of Biochemistry, Microbiology, and Immunology, Chung Shan Medical University, Taichung, 402, Taiwan
| | - Tsung-Yuan Yang
- Department of Internal Medicine, Chung-Shan Medical University Hospital, Taichung 402, Taiwan.,School of Medicine, Institute of Medicine, Chung Shan Medical University, Taichung 402, Taiwan
| | - Chia-Sheng Teng
- Institute of Biochemistry, Microbiology, and Immunology, Chung Shan Medical University, Taichung, 402, Taiwan
| | - Yi-Ju Lee
- Department of Pathology, School of Medicine, Chung Shan Medical University, Taichung City 402, Taiwan.,Department of Pathology, Chung Shan Medical University Hospital, Taichung City 402, Taiwan
| | - Meng-Hsun Yu
- Institute of Biochemistry, Microbiology, and Immunology, Chung Shan Medical University, Taichung, 402, Taiwan
| | - Huei-Jane Lee
- Institute of Biochemistry, Microbiology, and Immunology, Chung Shan Medical University, Taichung, 402, Taiwan.,Department of Biochemistry, School of Medicine, Medical College, Chung Shan Medical University, Taichung, 402, Taiwan
| | - Li-Sung Hsu
- Institute of Biochemistry, Microbiology, and Immunology, Chung Shan Medical University, Taichung, 402, Taiwan.,School of Medicine, Institute of Medicine, Chung Shan Medical University, Taichung 402, Taiwan.,Clinical Laboratory, Chung Shan Medical University Hospital, Taichung, 402, Taiwan
| | - Chau-Jong Wang
- Department of Health Diet and Industry Management, Chung Shan Medical University, Taichung 402, Taiwan.,Department of Medical Research, Chung Shan Medical University Hospital, Taichung, 402, Taiwan
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4
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Fonseca MDC, França A, Florentino RM, Fonseca RC, Lima Filho ACM, Vidigal PTV, Oliveira AG, Dubuquoy L, Nathanson MH, Leite MF. Cholesterol-enriched membrane microdomains are needed for insulin signaling and proliferation in hepatic cells. Am J Physiol Gastrointest Liver Physiol 2018; 315:G80-G94. [PMID: 29471671 PMCID: PMC6109708 DOI: 10.1152/ajpgi.00008.2018] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Hepatocyte proliferation during liver regeneration is a well-coordinated process regulated by the activation of several growth factor receptors, including the insulin receptor (IR). The IR can be localized in part to cholesterol-enriched membrane microdomains, but the role of such domains in insulin-mediated events in hepatocytes is not known. We investigated whether partitioning of IRs into cholesterol-enriched membrane rafts is important for the mitogenic effects of insulin in the hepatic cells. IR and lipid rafts were labeled in HepG2 cells and primary rat hepatocytes. Membrane cholesterol was depleted in vitro with metyl-β-cyclodextrin (MβCD) and in vivo with lovastatin. Insulin-induced calcium (Ca2+) signals studies were examined in HepG2 cells and in freshly isolated rat hepatocytes as well as in whole liver in vivo by intravital confocal imaging. Liver regeneration was studied by 70% partial hepatectomy (PH), and hepatocyte proliferation was assessed by PCNA staining. A subpopulation of IR was found in membrane microdomains enriched in cholesterol. Depletion of cholesterol from plasma membrane resulted in redistribution of the IR along the cells, which was associated with impaired insulin-induced nuclear Ca2+ signals, a signaling event that regulates hepatocyte proliferation. Cholesterol depletion also led to ERK1/2 hyper-phosphorylation. Lovastatin administration to rats decreased hepatic cholesterol content, disrupted lipid rafts and decreased insulin-induced Ca2+ signaling in hepatocytes, and delayed liver regeneration after PH. Therefore, membrane cholesterol content and lipid rafts integrity showed to be important for the proliferative effects of insulin in hepatic cells. NEW & NOTEWORTHY One of insulin's actions is to stimulate liver regeneration. Here we show that a subpopulation of insulin receptors is in a specialized cholesterol-enriched region of the cell membrane and this subfraction is important for insulin's proliferative effects.
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Affiliation(s)
- Matheus de Castro Fonseca
- 1Brazilian Biosciences National Laboratory, Brazilian Center for Research in Energy and Materials, Campinas, Sao Paulo, Brazil,2Department of Physiology and Biophysics, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Andressa França
- 2Department of Physiology and Biophysics, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil,3Department of Molecular Medicine, Federal University of Minas Gerais, Belo Horizonte, Brazil
| | - Rodrigo Machado Florentino
- 2Department of Physiology and Biophysics, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Roberta Cristelli Fonseca
- 2Department of Physiology and Biophysics, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil,4Center for Gastrointestinal Biology, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | | | - Paula Teixeira Vieira Vidigal
- 5Department of Pathological Anatomy and Forensic Medicine, Federal University of Minas Gerais, Belo Horizonte, Brazil
| | - André Gustavo Oliveira
- 2Department of Physiology and Biophysics, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil,4Center for Gastrointestinal Biology, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Laurent Dubuquoy
- 6Lille Inflammation Research International Center–UMR995, INSERM, University of Lille, Lille, France
| | - Michael H. Nathanson
- 7Section of Digestive Diseases, Department of Internal Medicine, Yale University, New Haven, Connecticut
| | - M. Fátima Leite
- 2Department of Physiology and Biophysics, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
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Yoon G, Oh CS, Kim HS. Distinctive expression patterns of hypoxia-inducible factor-1α and endothelial nitric oxide synthase following hypergravity exposure. Oncotarget 2018; 7:33675-88. [PMID: 27191892 PMCID: PMC5085111 DOI: 10.18632/oncotarget.9372] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2016] [Accepted: 05/05/2016] [Indexed: 01/13/2023] Open
Abstract
This study was designed to examine the expression of hypoxia-inducible factor-1α (HIF-1α) and the level and activity of endothelial nitric oxide synthase (eNOS) in the hearts and livers of mice exposed to hypergravity. Hypergravity-induced hypoxia and the subsequent post-exposure reoxygenation significantly increased cardiac HIF-1α levels. Furthermore, the levels and activity of cardiac eNOS also showed significant increase immediately following hypergravity exposure and during the reoxygenation period. In contrast, the expression of phosphorylated Akt (p-Akt) and phosphorylated extracellular signal-regulated kinase (p-ERK) showed significant elevation only during the reoxygenation period. These data raise the possibility that the increase in cardiac HIF-1α expression induced by reoxygenation involves a cascade of signaling events, including activation of the Akt and ERK pathways. In the liver, HIF-1α expression was significantly increased immediately after hypergravity exposure, indicating that hypergravity exposure to causes hepatocellular hypoxia. The hypergravity-exposed livers showed significantly higher eNOS immunoreactivity than did those of control mice. Consistent with these results, significant increases in eNOS activity and nitrate/nitrite levels were also observed. These findings suggest that hypergravity-induced hypoxia plays a significant role in the upregulation of hepatic eNOS.
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Affiliation(s)
- Gun Yoon
- Department of Obstetrics and Gynecology, Pusan National University Yangsan Hospital, Pusan National University School of Medicine, Yangsan-si, Gyeongsangnam-do, Republic of Korea
| | - Choong Sik Oh
- Aerospace Medicine Research Center, Republic of Korea Air Force Aerospace Medical Center, Cheongju-si, Chungcheongbuk-do, Republic of Korea
| | - Hyun-Soo Kim
- Department of Pathology, Severance Hospital, Yonsei University College of Medicine, Seoul, Republic of Korea
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6
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Fouda MA, El-Sayed SS, Abdel-Rahman AA. Restoration of Rostral Ventrolateral Medulla Cystathionine- γ Lyase Activity Underlies Moxonidine-Evoked Neuroprotection and Sympathoinhibition in Diabetic Rats. J Pharmacol Exp Ther 2017; 364:170-178. [PMID: 29133386 DOI: 10.1124/jpet.117.243865] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2017] [Accepted: 11/09/2017] [Indexed: 12/15/2022] Open
Abstract
We recently demonstrated a fundamental role for cystathionine-γ lyase (CSE)-derived hydrogen sulfide (H2S) in the cardioprotective effect of the centrally acting drug moxonidine in diabetic rats. Whether a downregulated CSE/H2S system in the rostral ventrolateral medulla (RVLM) underlies neuronal oxidative stress and sympathoexcitation in diabetes has not been investigated. Along with addressing this question, we tested the hypothesis that moxonidine prevents the diabetes-evoked neurochemical effects by restoring CSE/H2S function within its major site of action, the RVLM. Ex vivo studies were performed on RVLM tissues of streptozotocin (55 mg/kg, i.p.) diabetic rats treated daily for 3 weeks with moxonidine (2 or 6 mg/kg; gavage), H2S donor sodium hydrosulfide (NaHS) (3.4 mg/kg, i.p.), CSE inhibitor DL-propargylglycine (DLP) (37.5 mg/kg, i.p.), a combination of DLP with moxonidine, or their vehicle. Moxonidine alleviated RVLM oxidative stress, neuronal injury, and increased tyrosine hydroxylase immunoreactivity (sympathoexcitation) by restoring CSE expression/activity as well as heme oxygenase-1 (HO-1) expression. A pivotal role for H2S in moxonidine-evoked neuroprotection is supported by the following: 1) NaHS replicated the moxonidine-evoked neuroprotection, and the restoration of RVLM HO-1 expression in diabetic rats; and 2) DLP abolished moxonidine-evoked neuroprotection in diabetic rats, and caused RVLM neurotoxicity, reminiscent of a diabetes-evoked neuronal phenotype, in healthy rats. These findings suggest a novel role for RVLM CSE/H2S/HO-1 in moxonidine-evoked neuroprotection and sympathoinhibition, and as a therapeutic target for developing new drugs for alleviating diabetes-evoked RVLM neurotoxicity and cardiovascular anomalies.
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Affiliation(s)
- Mohamed A Fouda
- Department of Pharmacology, Brody School of Medicine, East Carolina University, Greenville, North Carolina
| | - Shaimaa S El-Sayed
- Department of Pharmacology, Brody School of Medicine, East Carolina University, Greenville, North Carolina
| | - Abdel A Abdel-Rahman
- Department of Pharmacology, Brody School of Medicine, East Carolina University, Greenville, North Carolina
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7
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Steagall RJ, Yao F, Shaikh SR, Abdel-Rahman AA. Estrogen receptor α activation enhances its cell surface localization and improves myocardial redox status in ovariectomized rats. Life Sci 2017; 182:41-49. [PMID: 28599865 PMCID: PMC5535783 DOI: 10.1016/j.lfs.2017.06.005] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2017] [Revised: 05/19/2017] [Accepted: 06/05/2017] [Indexed: 12/16/2022]
Abstract
AIMS Little is known about the role of subcellular trafficking of estrogen receptor (ER) subtypes in the acute estrogen (E2)-mediated alleviation of oxidative stress. We tested the hypothesis that ERα migration to the cardiac myocyte membrane mediates the acute E2-dependent improvement of cellular redox status. MAIN METHODS Myocardial distribution of subcellular ERα, ERβ and G-protein coupled estrogen receptor (GPER) was determined in proestrus sham-operated (SO) and in ovariectomized (OVX) rats, acutely treated with E2 (1μg/kg) or a selective ERα (PPT), ERβ (DPN) or GPER (G1) agonist (10μg/kg), by immunofluorescence and Western blot. We measured ROS and malondialdehyde (MDA) levels, and catalase and superoxide dismutase (SOD) activities to evaluate myocardial antioxidant/redox status. KEY FINDINGS Compared with SO, OVX rats exhibited higher myocardial ROS and MDA levels, reduced catalase and SOD activities, along with diminished ERα, and enhanced ERβ and GPER, localization at cardiomyocyte membrane. Acute E2 or an ERα (PPT), but not ERβ (DPN) or GPER (G1), agonist reversed these responses in OVX rats and resulted in higher ERα/ERβ and ERα/GPER ratios at the cardiomyocytes membrane. PPT or DPN enhanced myocardial Akt phosphorylation. We present the first evidence that preferential aggregation of ERα at the cardiomyocytes plasma membrane is ERα-dependent, and underlies E2-mediated reduction in oxidative stress, at least partly, via the enhancements of myocardial catalase and SOD activities in OVX rats. SIGNIFICANCE The findings highlight ERα agonists as potential therapeutics for restoring the myocardial redox status following E2 depletion in postmenopausal women.
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Affiliation(s)
- Rebecca J Steagall
- Department of Pharmacology and Toxicology, Brody School of Medicine, East Carolina University, Greenville, NC 27834, USA
| | - Fanrong Yao
- Department of Pharmacology and Toxicology, Brody School of Medicine, East Carolina University, Greenville, NC 27834, USA
| | - Saame Raza Shaikh
- Department of Biochemistry and Molecular Biology, East Carolina Diabetes & Obesity Institute, Brody School of Medicine, East Carolina University, Greenville, NC 27834, USA
| | - Abdel A Abdel-Rahman
- Department of Pharmacology and Toxicology, Brody School of Medicine, East Carolina University, Greenville, NC 27834, USA.
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8
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Caveolin-1 Function in Liver Physiology and Disease. Trends Mol Med 2016; 22:889-904. [DOI: 10.1016/j.molmed.2016.08.007] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2016] [Revised: 08/14/2016] [Accepted: 08/17/2016] [Indexed: 12/18/2022]
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Wang Y, Tong J, Chang B, Wang BF, Zhang D, Wang BY. Effects of ethanol on the expression of caveolin-1 in HepG2 cells. Mol Med Rep 2015; 11:4409-13. [PMID: 25651074 DOI: 10.3892/mmr.2015.3296] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2013] [Accepted: 06/09/2014] [Indexed: 11/05/2022] Open
Abstract
This study aimed to investigate the effects of ethanol on the expression of caveolin‑1 (CAV‑1) in HepG2 hepatocarcinoma cells. Ethanol‑treated HepG2 cells were investigated using the in vitro model to determine whether ethanol can influence the expression of CAV‑1. Cell viability was measured using the colorimetric 3‑(4, 5‑dimethylthiazol‑2‑yl)‑2,5‑diphenyltetrazolium bromide (MTT) and lactate dehydrogenase (LDH) assays. Expression of CAV‑1 was detected using western blot analysis. Quantitative PCR (qPCR) was used to determine CAV‑1 mRNA levels. The distribution of CAV‑1 in HepG2 cells was analyzed using immunofluorescence. The MTT assay results revealed that cell viability was not altered at ethanol concentrations of <1.0%, while ethanol concentrations >1.0% caused cell shedding, but not cell fragmentation. Western blot analysis showed significant differences in the levels of CAV‑1 expression between the control group and the 1.0% ethanol‑treated group at 6, 12 and 24 h (all P<0.05). qPCR showed significant differences in the expression levels of caveolin‑1 mRNA between the control group and the 1.0% ethanol‑treated group at 6 h, 12 h and 24 h (all P<0.05). Immunofluorescence demonstrated that CAV‑1 was distributed discontinuously at the boundaries of HepG2 cells. The results indicate that ethanol may increase the expression of CAV‑1 in HepG2 cells.
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Affiliation(s)
- Ying Wang
- Department of Gastroenterology, The First Affiliated Hospital of China Medical University, Shenyang, Liaoning 110001, P.R. China
| | - Jing Tong
- Department of Gastroenterology, The First Affiliated Hospital of China Medical University, Shenyang, Liaoning 110001, P.R. China
| | - Bing Chang
- Department of Gastroenterology, The First Affiliated Hospital of China Medical University, Shenyang, Liaoning 110001, P.R. China
| | - Bai-Fang Wang
- Department of Gastroenterology, The First Affiliated Hospital of China Medical University, Shenyang, Liaoning 110001, P.R. China
| | - Dai Zhang
- Department of Gastroenterology, The First Affiliated Hospital of China Medical University, Shenyang, Liaoning 110001, P.R. China
| | - Bing-Yuan Wang
- Department of Gastroenterology, The First Affiliated Hospital of China Medical University, Shenyang, Liaoning 110001, P.R. China
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10
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Gao L, Zhou Y, Zhong W, Zhao X, Chen C, Chen X, Gu Y, Chen J, Lv Z, Shen J. Caveolin-1 is essential for protecting against binge drinking-induced liver damage through inhibiting reactive nitrogen species. Hepatology 2014; 60:687-99. [PMID: 24710718 DOI: 10.1002/hep.27162] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/29/2013] [Accepted: 04/02/2014] [Indexed: 12/11/2022]
Abstract
UNLABELLED Caveolin-1 (Cav-1) is known to participate in many diseases, but its roles in alcoholic liver injury remain unknown. In the present study, we aimed to explore the roles of Cav-1 in protecting hepatocytes from ethanol-mediated nitrosative injury. We hypothesized that Cav-1 could attenuate ethanol-mediated nitrosative stress and liver damage through regulating epidermal growth factor receptor/signal transducer and activator of transcription 3/inducible nitric oxide synthase (EGFR/STAT3/iNOS)-signaling cascades. Ethanol-fed mice had time- and dose-dependent increases of Cav-1 in serum and liver with peak increase at 12 hours. Compared to wild-type mice, Cav-1 deficiency mice revealed higher expression of iNOS, higher levels of nitrate/nitrite and peroxynitrite, and had more serious liver damage, accompanied with higher levels of cleaved caspase-3 and apoptotic cell death in liver, and higher levels of alanine aminotransferase and aspartate aminotransferase in serum. Furthermore, the results revealed that the ethanol-mediated Cav-1 increase was in an extracellular signal-regulated kinase-dependent manner, and Cav-1 protected hepatocytes from ethanol-mediated apoptosis by inhibiting iNOS activity and regulating EGFR- and STAT3-signaling cascades. In agreement with these findings, clinical trials in human subjects revealed that serum Cav-1 level was time dependently elevated and peak concentration was observed 12 hours after binge drinking. Alcohol-induced liver lesions were negatively correlated with Cav-1 level, but positively correlated with nitrate/nitrite level, in serum of binge drinkers. CONCLUSIONS Cav-1 could be a cellular defense protein against alcoholic hepatic injury through inhibiting reactive nitrogen species and regulating EGFR/STAT3/iNOS-signaling cascades.
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Affiliation(s)
- Lei Gao
- School of Chinese Medicine, The University of Hong Kong, Pokfulam, Hong Kong SAR, China; School of Traditional Chinese Medicine, Southern Medical University, Guangzhou, China
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11
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Penumarti A, Abdel-Rahman AA. The novel endocannabinoid receptor GPR18 is expressed in the rostral ventrolateral medulla and exerts tonic restraining influence on blood pressure. J Pharmacol Exp Ther 2014; 349:29-38. [PMID: 24431468 DOI: 10.1124/jpet.113.209213] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Systemic administration of the G-protein-coupled receptor 18 (GPR18) agonist abnormal cannabidiol (Abn CBD) lowers blood pressure (BP). Whether GPR18 is expressed in the central nervous system (CNS) and plays a role in BP control is not known despite the abundance of the GPR18 ligand N-arachidonoyl glycine (NAGly) in the CNS. Therefore, we first determined whether GPR18 is expressed in the presympathetic tyrosine hydroxylase (TH) immunoreactive (ir) neurons of the brainstem cardiovascular regulatory nuclei. Second, we investigated the impact of GPR18 activation and blockade on BP and heart rate (HR) and neurochemical modulators of sympathetic activity and BP. Immunofluorescence findings revealed GPR18 expression in TH-ir neurons in the rostral ventrolateral medulla (RVLM). Intra-RVLM GPR18 activation (Abn CBD) and blockade (O-1918, 1,3-dimethoxy-5-methyl-2-[(1R,6R)-3-methyl-6-(1-methylethenyl)-2-,cyclohexen-1-yl]benzene) elicited dose-dependent reductions and elevations in BP, respectively, along with respective increases and decreases in HR in conscious male Sprague-Dawley rats. RVLM GPR18 activation increased neuronal adiponectin (ADN) and NO and reduced reactive oxygen species (ROS) levels, and GPR18 blockade reduced neuronal ADN and increased oxidative stress (i.e., ROS) in the RVLM. Finally, we hypothesized that the negligible hypotensive effect caused by the endogenous GPR18 ligand NAGly could be due to concurrent activation of CB(1)R in the RVLM. Our findings support this hypothesis because NAGly-evoked hypotension was doubled after RVLM CB(1)R blockade (SR141716, rimonabant). These findings are the first to demonstrate GPR18 expression in the RVLM and to suggest a sympathoinhibitory role for this receptor. The findings yield new insight into the role of a novel cannabinoid receptor (GPR18) in central BP control.
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Affiliation(s)
- Anusha Penumarti
- Department of Pharmacology and Toxicology, Brody School of Medicine, East Carolina University, Greenville, North Carolina
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12
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Subramanian K, Naik VD, Sathishkumar K, Sawant OB, Washburn SE, Wu G, Yallampalli C, Saade GR, Hankins GD, Ramadoss J. Interactive effects of in vitro binge-like alcohol and ATP on umbilical endothelial nitric oxide synthase post-translational modifications and redox modulation. Reprod Toxicol 2013; 43:94-101. [PMID: 24300283 DOI: 10.1016/j.reprotox.2013.11.006] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2013] [Revised: 10/29/2013] [Accepted: 11/22/2013] [Indexed: 01/01/2023]
Abstract
Alcohol dysregulates the regulation of reproductive vascular adaptations. We herein investigated chronic in vitro binge-like alcohol effects on umbilical endothelial nitric oxide synthase (eNOS) multi-site phosphorylation and related redox switches under basal (unstimulated) and stimulated (with ATP) states. Alcohol decreased endothelial excitatory (Pser1177)eNOS (P<0.001), whereas excitatory (Pser635)eNOS exhibited a main effect of alcohol (↓P=0.016) and ATP (↑P<0.001). Alcohol decreased (Pthr495)eNOS (P=0.004) levels, whereas inhibitory (Pser116)eNOS exhibited an alcohol main effect in both basal and stimulated states (↑P=0.005). Total eNOS was reduced by alcohol (P=0.038). In presence of ATP, alcohol inhibited ERK activity (P=0.002), whereas AKT exhibited no alcohol effect. Alcohol main effect on S-nitroso-glutathione reductase (↓P=0.031) and glutathione-S-transferase (↓P=0.027) were noted. Increased protein glutathiolation was noted, whereas no alcohol effect on GSH, GSSG, NOX2 or SOD expression was noted. Thus, alcohol effects on multi-site post-translational modifications and redox switches related to vasodilatory eNOS underscore the necessity for investigating alcohol-induced gestational vascular dysfunction.
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Affiliation(s)
- Kaviarasan Subramanian
- Department of Obstetrics and Gynecology, University of Texas Medical Branch, Galveston, TX, USA
| | - Vishal D Naik
- Department of Obstetrics and Gynecology, University of Texas Medical Branch, Galveston, TX, USA
| | - Kunju Sathishkumar
- Department of Obstetrics and Gynecology, University of Texas Medical Branch, Galveston, TX, USA
| | - Onkar B Sawant
- Department of Physiology and Pharmacology, Texas A&M University, College Station, TX, USA
| | - Shannon E Washburn
- Department of Physiology and Pharmacology, Texas A&M University, College Station, TX, USA
| | - Guoyao Wu
- Department of Animal Sciences, Texas A&M University, College Station, TX, USA
| | - Chandra Yallampalli
- Department of Obstetrics and Gynecology, University of Texas Medical Branch, Galveston, TX, USA
| | - George R Saade
- Department of Obstetrics and Gynecology, University of Texas Medical Branch, Galveston, TX, USA
| | - Gary D Hankins
- Department of Obstetrics and Gynecology, University of Texas Medical Branch, Galveston, TX, USA
| | - Jayanth Ramadoss
- Department of Obstetrics and Gynecology, University of Texas Medical Branch, Galveston, TX, USA.
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13
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Mandal S, Nelson VK, Mukhopadhyay S, Bandhopadhyay S, Maganti L, Ghoshal N, Sen G, Biswas T. 14-Deoxyandrographolide targets adenylate cyclase and prevents ethanol-induced liver injury through constitutive NOS dependent reduced redox signaling in rats. Food Chem Toxicol 2013; 59:236-48. [PMID: 23764359 DOI: 10.1016/j.fct.2013.05.056] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2012] [Revised: 04/25/2013] [Accepted: 05/29/2013] [Indexed: 02/07/2023]
Abstract
Chronic alcoholism is one of the most common causes of liver diseases worldwide. Nitric oxide (NO) has been proposed to have potential for clinical application against chronic hepatocellular injuries. However, mechanisms underlying hepatoprotective functions of NO in ethanol-induced apoptosis are largely unknown. Sprauge-Dawley rats were exposed to ethanol for 8 weeks. Half of the ethanol-fed animals received 14-deoxyandrographolide (14-DAG) treatment for the last 4 weeks of study. Preventive effect of 14-DAG against ethanol-induced hepatotoxicity involved constitutive nitric oxide synthase (cNOS) activation followed by up-regulation of γ-glutamylcysteine synthetase activity and reduced oxidative stress. Enhanced interaction of cNOS with caveolin-1 caused down-regulation of enzyme activity and led to depletion of NO in the hepatocytes of ethanol-fed animals. 14-DAG acted as activator of adenylate cyclase and modulated cyclic AMP (cAMP) mediated expression of caveolin-1 and calmodulin. This eventually favored activation of cNOS through inhibition of cNOS-caveolin-1 interaction. Our results suggest that, protective effect of 14-DAG against ethanol-induced hepatic injury is based on its ability to reduce oxidative stress through cNOS dependent improvement of redox status. 14-DAG mediated activation of adenylate cyclase-cAMP signaling leading to up-regulation of cNOS may provide a promising approach in the prevention of liver diseases during chronic alcoholism.
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Affiliation(s)
- Samir Mandal
- Cell Biology & Physiology Division, CSIR-Indian Institute of Chemical Biology, Kolkata, India
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14
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Feng H, Guo W, Han J, Li XA. Role of caveolin-1 and caveolae signaling in endotoxemia and sepsis. Life Sci 2013; 93:1-6. [PMID: 23727353 DOI: 10.1016/j.lfs.2013.05.016] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2012] [Revised: 05/09/2013] [Accepted: 05/14/2013] [Indexed: 12/28/2022]
Abstract
Caveolae, plasma membrane invaginations of 60-80nm in diameter, are a subset of lipid rafts enriched in cholesterol and sphingolipids. Caveolae are expressed in various tissues and cell types, such as endothelial cells, macrophages, neutrophils and adipocytes. The functions of caveolae are diverse and include endocytosis, transcytosis, potocytosis, calcium signaling, and regulation of various signaling events. Although growing evidence has increased our understanding of caveolae function, the role of caveolae in sepsis is still a controversial issue. In this review, we present a number of studies addressing caveolae and sepsis and describe the signaling pathways involved, including the LPS-eNOS-TLR4-NFκB, MKK3/p38 MAPK, cPLA2/p38 MAPK, STAT3/NFκB and IL-1β-IL-1R1 pathways. Different studies using endotoxemia and bacteremia animal models have provided distinct conclusions about the function of caveolae, and we discuss these inconsistencies. Taken together, the current data suggest that the function of caveolae in sepsis, which involves a number of signaling pathways, is complex and warrants further studies.
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Affiliation(s)
- Hong Feng
- Department of Tumor Research and Therapy Center, Provincial Hospital Affiliated to Shandong University, Jinan, Shandong 250021, China
| | - Wen Guo
- Taian Central Hospital, Taian, Shandong 271000, China
| | - Junqing Han
- Department of Tumor Research and Therapy Center, Provincial Hospital Affiliated to Shandong University, Jinan, Shandong 250021, China
| | - Xiang-An Li
- Department of Pediatrics, University of Kentucky College of Medicine, Lexington, KY 40536, United States.
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15
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Tang N, Farah B, He M, Fox S, Malouf A, Littner Y, Bearer CF. Ethanol causes the redistribution of L1 cell adhesion molecule in lipid rafts. J Neurochem 2011; 119:859-67. [PMID: 21884525 DOI: 10.1111/j.1471-4159.2011.07467.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Fetal alcohol spectrum disorder is estimated to affect 1% of live births. The similarities between children with fetal alcohol syndrome and those with mutations in the gene encoding L1 cell adhesion molecule (L1) implicates L1 as a target of ethanol developmental neurotoxicity. Ethanol specifically inhibits the neurite outgrowth promoting function of L1 at pharmacologic concentrations. Emerging evidence shows that localized disruption of the lipid rafts reduces L1-mediated neurite outgrowth. We hypothesize that ethanol impairment of the association of L1 with lipid rafts is a mechanism underlying ethanol's inhibition of L1-mediated neurite outgrowth. In this study, we examine the effects of ethanol on the association of L1 and lipid rafts. We show that, in vitro, L1 but not N-cadherin shifts into lipid rafts following treatment with 25 mM ethanol. The ethanol concentrations causing this effect are similar to those inhibiting L1-mediated neurite outgrowth. Increasing chain length of the alcohol demonstrates the same cutoff as that previously shown for inhibition of L1-L1 binding. In addition, in cerebellar granule neurons in which lipid rafts are disrupted with methyl-beta-cyclodextrin, the rate of L1-mediated neurite outgrowth on L1-Fc is reduced to background rate and that this background rate is not ethanol sensitive. These data indicate that ethanol may inhibit L1-mediated neurite outgrowth by retarding L1 trafficking through a lipid raft compartment.
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Affiliation(s)
- Ningfeng Tang
- Department of Pediatrics, University of Maryland School of Medicine, Baltimore, Maryland 21209, USA
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16
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Ibrahim BM, Abdel-Rahman AA. Role of brainstem GABAergic signaling in central cannabinoid receptor evoked sympathoexcitation and pressor responses in conscious rats. Brain Res 2011; 1414:1-9. [PMID: 21840505 DOI: 10.1016/j.brainres.2011.07.046] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2011] [Revised: 07/15/2011] [Accepted: 07/22/2011] [Indexed: 12/20/2022]
Abstract
The mechanisms implicated in the sympathoexcitation and pressor responses elicited by central CB₁R activation are not fully understood. Further, the few reported mechanistic studies on this endeavor were conducted in anesthetized rats. Therefore, it was important to identify the dose-related cardiovascular responses elicited by central administration of the cannabinoid receptor (CB₁R) agonist WIN55,212-2 in conscious rats. The second and main objective of the study was to test the hypothesis that brainstem GABAergic transmission is implicated in the CB₁R-evoked sympathoexcitation/pressor response. In conscious rats, intracisternal (i.c) WIN55,212-2 (3, 10, 30 μg/rat) elicited dose-dependent increases in mean arterial pressure (MAP) and plasma norepinephrine (NE; index of sympathoexcitation), and reduced heart rate (HR). Subsequent neurochemical studies showed that i.c WIN55,212-2 (15 μg/rat) significantly increased the number and percentage of neurons that exhibited dual immunostaining for tyrosine hydroxylase (catecholaminergic neurons) and c-Fos (marker of neuronal activity) within the rostral ventrolateral medulla, which suggests enhanced central sympathetic tone. These neurochemical responses along with the increases in MAP and plasma NE were drastically attenuated by prior: (i) blockade of central CB₁R by i.c AM251 (30 μg/rat) or (ii) activation of central GABA(A)R by i.c muscimol (0.1 μg/rat). Collectively, these neurochemical and cardiovascular findings are the first to suggest a pivotal role for the inhibition of brainstem GABAergic transmission in the central CB₁R-evoked sympathoexcitation/pressor response in conscious rats.
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Affiliation(s)
- Badr Mostafa Ibrahim
- Department of Pharmacology & Toxicology, Brody School of Medicine, East Carolina University, Greenville, NC 27858, USA
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17
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Ramadoss J, Liao WX, Chen DB, Magness RR. High-throughput caveolar proteomic signature profile for maternal binge alcohol consumption. Alcohol 2010; 44:691-7. [PMID: 20053519 DOI: 10.1016/j.alcohol.2009.10.010] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2009] [Revised: 10/12/2009] [Accepted: 10/16/2009] [Indexed: 12/21/2022]
Abstract
Currently, no single marker is sensitive and specific enough to be considered a reliable biomarker for prenatal alcohol exposure. To identify a proteomic signature profile for maternal alcohol consumption, we carried out high-throughput proteomics on maternal endothelial caveolae exposed to moderate binge-like alcohol conditions. In these specialized lipid-ordered microdomains that contain a rich assembly of proteins, we demonstrate that moderate binge-like alcohol resulted in a distinctive maternal caveolar proteomic signature with important proteins being dramatically decreased/knocked out in the alcoholic profile. These proteins span from histones and basic structural proteins like α tubulin to proteins involved in trafficking, deubiquitination, cell signaling, and cell-cell adhesion. The profile also suggests an important role for the mother and the uteroplacental compartment in the pathogenesis of fetal alcohol spectrum disorders (FASD). These data demonstrate that the caveolar proteomic signature created by alcohol shows a promising direction for early detection of FASD.
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18
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Husain K, Ferder L, Ansari RA, Lalla J. Chronic ethanol ingestion induces aortic inflammation/oxidative endothelial injury and hypertension in rats. Hum Exp Toxicol 2010; 30:930-9. [PMID: 20921064 DOI: 10.1177/0960327110384520] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The study aim was to investigate the relationship of chronic ethanol-induced inflammation leading to vascular endothelial injury and elevation of blood pressure (BP) in a rat model. Male Fisher rats were divided into two groups of six animals each and treated as follows: (1) Control (5% sucrose, orally) daily for 12 weeks and (2) 20% ethanol (4 g kg(-1), orally) daily for 12 weeks. The mean arterial blood pressure was recorded every week. The animals were anesthetized with pentobarbital after 12 weeks; thoracic aorta were isolated and analyzed for aortic reactivity response, inflammatory mediators, oxidant/antioxidant enzyme protein expression and endothelial nitric oxide-generating system. The results show that the mean BP was significantly elevated 12 weeks after ethanol ingestion. The increased BP was related to increased aortic inflammation (tumor necrosis factor [TNF]-α; nitric oxide synthase [iNOS], COX-2 and MCP-1 protein expression) and elevated angiotensin II levels in alcohol-treated group compared to control. Aortic Nicotinamide adenine dinucleotide phosphate reduced (NADPH) oxidase activity, membrane and cytosolic subunits p22(phox) and p47(phox) expression and Mn-SOD activity and protein expression significantly increased, whereas nitric oxide (NO), endothelial NO synthase (eNOS), vascular endothelial growth factor (VEGF)-A and CuZn-SOD activity and protein expression significantly decreased in alcohol-treated group compared to control. The acetylcholine-mediated vasorelaxation response was depressed in the aorta of ethanol-treated rats compared to control. In conclusion, chronic ethanol-induced elevation in BP is related to increased aortic inflammation, elevated angiotensin II levels, induction of NADPH oxidase causing endothelial injury, depletion of CuZn-SOD, down-regulation of endothelial NO generating system and impaired vascular relaxation in rats.
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Affiliation(s)
- Kazim Husain
- Department of Physiology, Pharmacology and Toxicology, Ponce School of Medicine, Ponce, PR, USA.
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19
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Targeted mutation of Cav-1 alleviates the effect of endotoxin in the inhibition of ET-1-mediated eNOS activation in the liver. Shock 2010; 33:392-8. [PMID: 19730165 DOI: 10.1097/shk.0b013e3181be3e99] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Dysfunction of hepatic microcirculation during inflammatory stress conditions is associated with overexpression of caveolin 1 (Cav-1) in sinusoidal endothelial cells. Because Cav-1 binds and inhibits eNOS, it was suggested that Cav-1 overexpression inhibits endothelin 1 (ET-1)-mediated eNOS activation after endotoxemia in the liver; however, a causal link between stress-mediated suppression of eNOS and Cav-1 overexpression has not been fully established. We hypothesize that genetic knockout of Cav-1 reverses the LPS-suppressed ET-1-mediated eNOS activation. In this report, liver sinusoidal endothelial cells (LSECs) from wild-type (WT) and Cav-1 knockout (KO) mice were isolated, pretreated with 100 ng/mL LPS for 6 h, and treated with 10 nmol ET-1 for 30 min. Data showed that LPS increased Cav-1 protein expression (+88%; P < 0.05) and inhibited ET-1-mediated eNOS activation and NO production in WT LSECs. Genetic deletion of Cav-1 increased basal eNOS activity (0.40 in KO vs. 0.15 fmol/min per well in WT; +262%; P < 0.05) and reversed LPS inhibition of ET-1-stimulated eNOS activity (+25.7%; P < 0.05) by increasing eNOS-Ser1177 (+40.3%; P < 0.05) and decreasing eNOS-threonine-495 (-8.8%; P < 0.05) phosphorylation. The reversal of LPS inhibition resulted in an increase in ET-1-induced eNOS translocation to the plasma membrane and an augmentation of NO production in the perinuclear region and plasma membrane of Cav-1 KO LSECs. These results showed that genetic knockout of Cav-1 increased basal eNOS activity and at least partially restored ET-1-mediated eNOS translocation and NO production in LSECs after LPS treatment. In conclusion, Cav-1 overexpression is a requirement for decreased eNOS activity in LSECs after endotoxemia.
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20
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Lai ZW, Lew RA, Yarski MA, Mu FT, Andrews RK, Smith AI. The identification of a calmodulin-binding domain within the cytoplasmic tail of angiotensin-converting enzyme-2. Endocrinology 2009; 150:2376-81. [PMID: 19164471 PMCID: PMC7108506 DOI: 10.1210/en.2008-1274] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Angiotensin-converting enzyme (ACE)-2 is a homolog of the well-characterized plasma membrane-bound angiotensin-converting enzyme. ACE2 is thought to play a critical role in regulating heart function, and in 2003, ACE2 was identified as a functional receptor for severe acute respiratory syndrome coronavirus. We have recently shown that like ACE, ACE2 undergoes ectodomain shedding and that this shedding event is up-regulated by phorbol esters. In the present study, we used gel shift assays to demonstrate that calmodulin, an intracellular calcium-binding protein implicated in the regulation of other ectodomain shedding events, binds a 16-amino acid synthetic peptide corresponding to residues 762-777 within the cytoplasmic domain of human ACE2, forming a calcium-dependent calmodulin-peptide complex. Furthermore, we have demonstrated that ACE2 expressed in Chinese hamster ovary cells specifically binds to glutathione-S-transferase-calmodulin, but not glutathione-S-transferase alone, in pull-down assays using cell lysates. Finally, to investigate whether calmodulin has any effect on ACE2 ectodomain shedding in cells that endogenously express the enzyme, cells from a human liver cell line (Huh-7) expressing ACE2 were incubated with calmodulin-specific inhibitors, trifluoperazine and calmidazolium. Both trifluoperazine (25 micromol/liter) and calmidazolium, (25 micromol/liter) significantly increased the release of ACE2 into the medium (44.1 +/- 10.8%, P < 0.05, Student's t test; unpaired, two-tailed, and 51.1 +/- 7.4% P < 0.05, one-way ANOVA, respectively;), as analyzed by an ACE2-specific quenched fluorescence substrate assay. We also show that the calmodulin-specific inhibitor-stimulated shedding of ACE2 is independent from phorbol ester-induced shedding. In summary, we have demonstrated that calmodulin is able to bind ACE2 and suggest that the ACE2 ectodomain shedding and/or sheddase(s) activation regulated by calmodulin is independent from the phorbol ester-induced shedding.
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Affiliation(s)
- Zon W Lai
- Department of Biochemistry and Molecular Biology, Monash University, Wellington Road, Clayton, Victoria 3800, Australia
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21
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Mantena SK, King AL, Andringa KK, Eccleston HB, Bailey SM. Mitochondrial dysfunction and oxidative stress in the pathogenesis of alcohol- and obesity-induced fatty liver diseases. Free Radic Biol Med 2008; 44:1259-72. [PMID: 18242193 PMCID: PMC2323912 DOI: 10.1016/j.freeradbiomed.2007.12.029] [Citation(s) in RCA: 333] [Impact Index Per Article: 20.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/18/2007] [Revised: 12/19/2007] [Accepted: 12/19/2007] [Indexed: 12/16/2022]
Abstract
Fatty liver disease associated with chronic alcohol consumption or obesity/type 2 diabetes has emerged as a serious public health problem. Steatosis, accumulation of triglyceride in hepatocytes, is now recognized as a critical "first-hit" in the pathogenesis of liver disease. It is proposed that steatosis "primes" the liver to progress to more severe liver pathologies when individuals are exposed to subsequent metabolic and/or environmental stressors or "second-hits." Genetic risk factors can also influence the susceptibility to and severity of fatty liver disease. Furthermore, oxidative stress, disrupted nitric oxide (NO) signaling, and mitochondrial dysfunction are proposed to be key molecular events that accelerate or worsen steatosis and initiate progression to steatohepatitis and fibrosis. This review article will discuss the following topics regarding the pathobiology and molecular mechanisms responsible for fatty liver disease: (1) the "two-hit" or "multi-hit" hypothesis, (2) the role of mitochondrial bioenergetic defects and oxidant stress, (3) the interplay between NO and mitochondria in fatty liver disease, (4) genetic risk factors and oxidative stress-responsive genes, and (5) the feasibility of antioxidants for treatment.
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Affiliation(s)
| | | | | | | | - Shannon M. Bailey
- *Corresponding Author: Shannon M. Bailey, PhD, Associate Professor, Department of Environmental Health Sciences, Center for Free Radical Biology, University of Alabama at Birmingham, Ryals Building, Room 623, 1530 3 Avenue South, Birmingham, AL 35294 USA, Phone: 205-934-7070, Fax: 205-975-6341,
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22
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Zhang J, Abdel-Rahman AA. Inhibition of nischarin expression attenuates rilmenidine-evoked hypotension and phosphorylated extracellular signal-regulated kinase 1/2 production in the rostral ventrolateral medulla of rats. J Pharmacol Exp Ther 2007; 324:72-8. [PMID: 17940198 DOI: 10.1124/jpet.107.129049] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Imidazoline (I(1))-evoked hypotension is linked to enhanced phosphorylated extracellular signal-regulated kinase (pERK)1/2 production in the rostral ventrolateral medulla (RVLM). Recent cell culture findings suggest that nischarin is a candidate for the I(1) receptor. In the present study, nischarin antisense oligodeoxynucleotide (ODN) (AS1 or AS2), designed according to nischarin cDNA sequence, was administered intracisternally (i.c., 2 nmol/rat for 2 days) to knockdown central nischarin expression; control rats received the corresponding mismatched ODN (MM1 or MM2) or artificial cerebrospinal fluid (aCSF). We investigated the effects of AS1 or AS2 on nischarin expression in the RVLM, and on the hypotension and RVLM pERK1/2 production elicited by the I(1)-selective agonist rilmenidine (25 mug/rat i.c.). Compared with aCSF, the mismatched ODN (MM1 or MM2) had no significant effect on RVLM nischarin expression or the cardiovascular and cellular (RVLM pERK1/2) responses elicited by rilmenidine. However, either antisense ODN substantially (>80%) reduced nischarin expression in the RVLM (AS1/MM1, 3 +/- 1 versus 32 +/- 2 positive cells; AS2/MM2, 4 +/- 1 versus 31 +/- 2 positive cells) and abrogated rilmenidine (I(1))-evoked hypotension (AS1/MM1, -4.1 +/- 0.9 versus -10.8 +/- 1.9 mm Hg; AS2/MM2, -2.1 +/- 1.1 versus -15.3 +/- 2.5 mm Hg) and ERK1/2 activation in the RVLM (AS1/MM1, 10 +/- 1 versus 15 +/- 2 positive cells; AS2/MM2, 9 +/- 1 versus 18 +/- 2 positive cells). Finally, pERK1/2 generated by central I(1) receptor activation is colocalized with nischarin in the RVLM neurons. This is the first evidence in vivo that nischarin plays a critical role in I(1) receptor-mediated pERK1/2 production in the RVLM and the subsequent hypotension.
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Affiliation(s)
- Jian Zhang
- Department of Pharmacology and Toxicology, Brody School of Medicine, East Carolina University, Greenville, NC 27834, USA
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23
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Frossard JL, Schiffer E, Cikirikcioglu B, Bourquin J, Morel DR, Pastor CM. Opposite regulation of endothelial NO synthase by HSP90 and caveolin in liver and lungs of rats with hepatopulmonary syndrome. Am J Physiol Gastrointest Liver Physiol 2007; 293:G864-70. [PMID: 17921448 DOI: 10.1152/ajpgi.00136.2007] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The hepatopulmonary syndrome is a complication of cirrhosis that associates an overproduction of nitric oxide (NO) in lungs and a NO defect in the liver. Because endothelial NO synthase (eNOS) is regulated by caveolin that decreases and heat shock protein 90 (HSP90) that increases NO production, we hypothesized that an opposite regulation of eNOS by caveolin and HSP90 might explain the opposite NO production in both organs. Cirrhosis was induced by a chronic bile duct ligation (CBDL) performed 15, 30, and 60 days before sample collection and pharmacological tests. eNOS, caveolin, and HSP90 expression were measured in hepatic and lung tissues. Pharmacological tests to assess NO released by shear stress and by acetylcholine were performed in livers (n = 28) and lungs (n = 28) isolated from normal and CBDL rats. In lungs from CBDL rats, indirect evidence of high NO production induced by shear stress was associated with a high binding of HSP90 and a low binding of caveolin to eNOS. Opposite results were observed in livers from CBDL rats. Our study shows an opposite posttranslational regulation of eNOS by HSP90 and caveolin in lungs and liver from rats with CBDL. Such opposite posttranslational regulation of eNOS by regulatory proteins may explain in part the pulmonary overproduction of NO and the hepatic NO defect in rats with hepatopulmonary syndrome.
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Affiliation(s)
- Jean-Louis Frossard
- Laboratoire de Physiopathologie Hépatique et Imagerie Moléculaire, Hôpitaux Universitaires de Genève, Rue Micheli-du-Crest, 24, 1205 Geneva, Switzerland
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24
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Husain K, Vazquez M, Ansari RA, Malafa MP, Lalla J. Chronic alcohol-induced oxidative endothelial injury relates to angiotensin II levels in the rat. Mol Cell Biochem 2007; 307:51-8. [PMID: 17721810 DOI: 10.1007/s11010-007-9583-6] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2007] [Accepted: 08/10/2007] [Indexed: 12/13/2022]
Abstract
The link between chronic alcohol consumption and cardiovascular injury including hypertension is well known. However, molecular mediators implicated with alcohol-induced elevation in blood pressure (BP) remain elusive. The aim of this study was to investigate the relationship of chronic ethanol-induced endothelial injury and elevation in BP with angiotensin II levels in rats. Male Fisher rats were divided into two groups of seven animals each and treated as follows: (1) Control (5% sucrose, orally) daily for 12 weeks and (2) ethanol (4 g kg(-1), orally) daily for 12 weeks. The BP (systolic, diastolic, and mean) was recorded every week. The animals were anesthetized with pentobarbital after 12 weeks; blood and thoracic aorta were isolated and analyzed for aortic reactivity response, angiotensin II levels, and oxidative endothelial injury. The results show that the systolic, diastolic, and mean BP were significantly elevated 12 weeks after ethanol ingestion. The increased BP was related to elevated angiotensin II levels in the plasma and aorta of alcohol treated group compared to control. The aortic NADPH oxidase activity, ratio of oxidized to reduced glutathione (GSSG/GSH) and lipid peroxidation significantly increased, whereas nitric oxide (NO), endothelial NO synthase (eNOS), and vascular endothelial growth factor (VEGF) protein expressions were depressed in alcohol group compared to control. The phenylephrine-mediated vasoconstriction response was not altered, while acetylcholine-mediated vasorelaxation response was depressed in the aorta of ethanol treated rats compared to control. It is concluded that chronic ethanol ingestion induces hypertension which is correlated with elevated tissue angiotensin II levels, activation of NADPH oxidase activity causing endothelial injury, depletion of endothelial NO generating system, and impaired vascular relaxation in rats.
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Affiliation(s)
- Kazim Husain
- Department of Physiology, Pharmacology and Toxicology, Ponce School of Medicine, Ponce, PR 00732, USA.
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25
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Bujanda L, García-Barcina M, Juan VGD, Bidaurrazaga J, de Luco MF, Gutiérrez-Stampa M, Larzabal M, Hijona E, Sarasqueta C, Echenique-Elizondo M, Arenas JI. Effect of resveratrol on alcohol-induced mortality and liver lesions in mice. BMC Gastroenterol 2006; 6:35. [PMID: 17105669 PMCID: PMC1657014 DOI: 10.1186/1471-230x-6-35] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/10/2006] [Accepted: 11/14/2006] [Indexed: 12/23/2022] Open
Abstract
BACKGROUND Resveratrol is a polyphenol with important antiinflammatory and antioxidant properties. We investigated the effect of resveratrol on alcohol-induced mortality and liver lesions in mice. METHODS Mice were randomly distributed into four groups (control, resveratrol-treated control, alcohol and resveratrol-treated alcohol). Chronic alcohol intoxication was induced by progressively administering alcohol in drinking water up to 40% v/v. The mice administered resveratrol received 10 mg/ml in drinking water. The animals had free access to standard diet. Blood levels were determined for transaminases, IL-1 and TNF-alpha. A histological evaluation was made of liver damage, and survival among the animals was recorded. RESULTS Transaminase concentration was significantly higher in the alcohol group than in the rest of the groups (p < 0.05). IL-1 levels were significantly reduced in the alcohol plus resveratrol group compared with the alcohol group (p < 0.05). TNF-alpha was not detected in any group. Histologically, the liver lesions were more severe in the alcohol group, though no significant differences between groups were observed. Mortality in the alcohol group was 78% in the seventh week, versus 22% in the alcohol plus resveratrol group (p < 0.001). All mice in the alcohol group died before the ninth week. CONCLUSION The results obtained suggest that resveratrol reduces mortality and liver damage in mice.
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Affiliation(s)
- Luis Bujanda
- Department of Gastroenterology, Donostia Hospital, San Sebastián, Spain
| | | | | | | | | | | | | | - Elisabeth Hijona
- Department of Gastroenterology, Donostia Hospital, San Sebastián, Spain
| | | | | | - Juan I Arenas
- Department of Gastroenterology, Donostia Hospital, San Sebastián, Spain
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Yuan GJ, Zhou XR, Gong ZJ, Zhang P, Sun XM, Zheng SH. Expression and activity of inducible nitric oxide synthase and endothelial nitric oxide synthase correlate with ethanol-induced liver injury. World J Gastroenterol 2006; 12:2375-81. [PMID: 16688828 PMCID: PMC4088073 DOI: 10.3748/wjg.v12.i15.2375] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AIM: To study the expression and activity of inducible nitric oxide synthase (iNOS) and endothelial nitric oxide synthase (eNOS) in rats with ethanol-induced liver injury and their relation with liver damage, activation of nuclear factor-κB (NF-κB) and tumor necrosis factor-α (TNF-α) expression in the liver.
METHODS: Female Sprague-Dawley rats were given fish oil (0.5 mL) along with ethanol or isocaloric dextrose daily via gastrogavage for 4 or 6 wk. Liver injury was assessed using serum alanine aminotransferase (ALT) activity and pathological analysis. Liver malondialdehyde (MDA), nitric oxide contents, iNOS and eNOS activity were determined. NF-κB p65,iNOS, eNOS and TNF-α protein or mRNA expression in the liver were detected by immunohistochemistry or reverse transcriptase-polymerase chain reaction (RT-PCR).
RESULTS: Chronic ethanol gavage for 4 wk caused steatosis, inflammation and necrosis in the liver, and elevated serum ALT activity. Prolonged ethanol administration (6 wk) enhanced the liver damage. These responses were accompanied with increased lipid peroxidation, NO contents, iNOS activity and reduced eNOS activity. NF-κB p65, iNOS and TNF-α protein or mRNA expression were markedly induced after chronic ethanol gavage, whereas eNOS mRNA expression remained unchanged. The enhanced iNOS activity and expression were positively correlated with the liver damage, especially the necro-inflammation, activation of NF-κB, and TNF-α mRNA expression.
CONCLUSION: iNOS expression and activity are induced in the liver after chronic ethanol exposure in rats, which are correlated with the liver damage, especially the necro-inflammation, activation of NF-κB and TNF-α expression. eNOS activity is reduced, but its mRNA expression is not affected.
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Affiliation(s)
- Guang-Jin Yuan
- Department of Infectious Diseases, Renmin Hospital of Wuhan University, Wuhan 430060, Hubei Province, China
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El-Mas MM, Zhang J, Abdel-Rahman AA. Upregulation of vascular inducible nitric oxide synthase mediates the hypotensive effect of ethanol in conscious female rats. J Appl Physiol (1985) 2005; 100:1011-8. [PMID: 16293701 DOI: 10.1152/japplphysiol.01058.2005] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Previous reports from our laboratory have shown that ethanol elicits hypotension in female but not in male rats and that this effect of ethanol is estrogen dependent (El-Mass MM and Abdel-Rahman AA. Alcohol Clin Exp Res 23: 624-632, 1999; El-Mass MM and Abdel-Rahman AA. Clin Exp Hypertens 21: 1429-1445, 1999). In the present study, we tested the hypothesis that ethanol lowers blood pressure in female rats via upregulation of the inducible nitric oxide synthase (iNOS) in vascular tissues. The effects of pretreatment with NG-nitro-L-arginine (NOARG; nonselective nitric oxide synthase inhibitor) or aminoguanidine (selective iNOS inhibitor) on hemodynamic responses elicited by intragastric (ig) ethanol were determined in conscious female rats. Changes in vascular (aortic) iNOS protein expression evoked by ethanol in the presence and absence of aminoguanidine were also measured by immunohistochemistry. Compared with control (water treated) female rats, ethanol (1 g/kg ig) elicited hypotension that was associated with a significant increase in the aortic iNOS activity. The hypotensive effect of ethanol was virtually abolished in rats infused with the nitric oxide synthase inhibitor NOARG, suggesting a role for nitric oxide in ethanol hypotension. The inability of ethanol to lower blood pressure in NOARG-treated rats cannot be attributed to the presence of elevated blood pressure in these rats because ethanol produced hypotension when blood pressure was raised to comparable levels with phenylephrine infusion. Selective inhibition of iNOS by aminoguanidine (45 mg/kg ip), which had no effect on baseline blood pressure, abolished both the hypotensive action of subsequently administered ethanol and the associated increases in aortic iNOS content. These findings implicate vascular iNOS, at least partly, in the acute hypotensive action of ethanol in female rats.
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Affiliation(s)
- Mahmoud M El-Mas
- Dept. of Pharmacology, School of Medicine, East Carolina Univ., Greenville, NC 27858, USA
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