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Karasaki K, Kokubo H, Bumdelger B, Kaji N, Sakai C, Ishida M, Yoshizumi M. Angiotensin II Type 1 Receptor Blocker Prevents Abdominal Aortic Aneurysm Progression in Osteoprotegerin-Deficient Mice via Upregulation of Angiotensin (1-7). J Am Heart Assoc 2023; 12:e027589. [PMID: 36718875 PMCID: PMC9973615 DOI: 10.1161/jaha.122.027589] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Background Angiotensin II type 1 receptor blockers (ARBs) have been shown to limit the growth of abdominal aortic aneurysm (AAA), but their efficacy is controversial. This study aimed to investigate the molecular mechanism underlying the protective effect of ARBs against AAA progression. Methods and Results Olmesartan, an ARB, was administered to wild-type and osteoprotegerin-knockout (Opg-KO) mice starting 2 weeks before direct application of CaCl2 to aortas to induce AAA. The protective effect of olmesartan against AAA in wild-type and Opg-KO mice was compared at 6 weeks after AAA induction. Olmesartan prevented AAA progression in Opg-KO mice, including excessive aortic dilatation and collapse of tunica media, but not in wild-type mice. Deficiency of the Opg gene is known to cause excessive activation of the tumor necrosis factor-related apoptosis-inducing ligand-induced c-Jun N-terminal kinase/matrix metalloproteinase 9 pathway, resulting in prolonged AAA progression. Olmesartan attenuated the upregulation of phosphorylated c-Jun N-terminal kinase and matrix metalloproteinase 9 expression in the aortic wall of Opg-KO mice. In cultured vascular smooth muscle cells, tumor necrosis factor-related apoptosis-inducing ligand-induced c-Jun N-terminal kinase phosphorylation and matrix metalloproteinase 9 expression were inhibited by angiotensin (1-7), the circulating levels of which are increased by ARBs. Furthermore, administering an angiotensin (1-7) antagonist to Opg-KO mice diminished the protective effect of olmesartan against AAA progression. Conclusions Olmesartan prevented AAA progression in Opg-KO mice by upregulating angiotensin (1-7), suggesting that angiotensin (1-7) may be a key factor that mediates the protective effect of ARBs.
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Affiliation(s)
- Kohei Karasaki
- Department of Cardiovascular Physiology and Medicine, Graduate School of Biomedical and Health SciencesHiroshima UniversityHiroshimaJapan
| | - Hiroki Kokubo
- Department of Cardiovascular Physiology and Medicine, Graduate School of Biomedical and Health SciencesHiroshima UniversityHiroshimaJapan
| | - Batmunkh Bumdelger
- Department of Cardiovascular Physiology and Medicine, Graduate School of Biomedical and Health SciencesHiroshima UniversityHiroshimaJapan
| | - Nobuchika Kaji
- Department of Cardiovascular Physiology and Medicine, Graduate School of Biomedical and Health SciencesHiroshima UniversityHiroshimaJapan
| | - Chiemi Sakai
- Department of Cardiovascular Physiology and Medicine, Graduate School of Biomedical and Health SciencesHiroshima UniversityHiroshimaJapan
| | - Mari Ishida
- Department of Cardiovascular Physiology and Medicine, Graduate School of Biomedical and Health SciencesHiroshima UniversityHiroshimaJapan
| | - Masao Yoshizumi
- Department of Cardiovascular Physiology and Medicine, Graduate School of Biomedical and Health SciencesHiroshima UniversityHiroshimaJapan
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Chen Q, Gao Y, Yang F, Deng H, Wang Y, Yuan L. Angiotensin-converting enzyme 2 improves hepatic insulin resistance by regulating GABAergic signaling in the liver. J Biol Chem 2022; 298:102603. [PMID: 36265585 PMCID: PMC9668738 DOI: 10.1016/j.jbc.2022.102603] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2022] [Revised: 10/07/2022] [Accepted: 10/10/2022] [Indexed: 11/07/2022] Open
Abstract
The angiotensin-converting enzyme 2 (ACE2)/angiotensin 1-7/MAS axis and the gamma-aminobutyric acid (GABA)ergic signaling system have both been shown to have the dual potential to improve insulin resistance (IR) and hepatic steatosis associated with obesity in the liver. Recent studies have demonstrated that ACE2 can regulate the GABA signal in various tissues. Notwithstanding this evidence, the functional relationship between ACE2 and GABA signal in the liver under IR remains elusive. Here, we used high-fat diet-induced models of IR in C57BL/6 mice as well as ACE2KO and adeno-associated virus-mediated ACE2 overexpression mouse models to address this knowledge gap. Our analysis showed that glutamate decarboxylase (GAD)67/GABA signaling was weakened in the liver during IR, whereas the expression of GAD67 and GABA decreased significantly in ACE2KO mice. Furthermore, exogenous administration of angiotensin 1-7 and adeno-associated virus- or lentivirus-mediated overexpression of ACE2 significantly increased hepatic GABA signaling in models of IR both in vivo and in vitro. We found that this treatment prevented lipid accumulation and promoted fatty acid β oxidation in hepatocytes as well as inhibited the expression of gluconeogenesis- and inflammation-related genes, which could be reversed by allylglycine, a specific GAD67 inhibitor. Collectively, our findings show that signaling via the ACE2/A1-7/MAS axis can improve hepatic IR by regulating hepatic GABA signaling. We propose that this research might indicate a potential strategy for the management of diabetes.
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Memon B, Abdelalim EM. ACE2 function in the pancreatic islet: Implications for relationship between SARS-CoV-2 and diabetes. Acta Physiol (Oxf) 2021; 233:e13733. [PMID: 34561952 PMCID: PMC8646749 DOI: 10.1111/apha.13733] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2021] [Revised: 09/15/2021] [Accepted: 09/20/2021] [Indexed: 01/08/2023]
Abstract
The molecular link between SARS-CoV-2 infection and susceptibility is not well understood. Nonetheless, a bi-directional relationship between SARS-CoV-2 and diabetes has been proposed. The angiotensin-converting enzyme 2 (ACE2) is considered as the primary protein facilitating SARS-CoV and SARS-CoV-2 attachment and entry into the host cells. Studies suggested that ACE2 is expressed in the endocrine cells of the pancreas including beta cells, in addition to the lungs and other organs; however, its expression in the islets, particularly beta cells, has been met with some contradiction. Importantly, ACE2 plays a crucial role in glucose homoeostasis and insulin secretion by regulating beta cell physiology. Given the ability of SARS-CoV-2 to infect human pluripotent stem cell-derived pancreatic cells in vitro and the presence of SARS-CoV-2 in pancreatic samples from COVID-19 patients strongly hints that SARS-CoV-2 can invade the pancreas and directly cause pancreatic injury and diabetes. However, more studies are required to dissect the underpinning molecular mechanisms triggered in SARS-CoV-2-infected islets that lead to aggravation of diabetes. Regardless, it is important to understand the function of ACE2 in the pancreatic islets to design relevant therapeutic interventions in combatting the effects of SARS-CoV-2 on diabetes pathophysiology. Herein, we detail the function of ACE2 in pancreatic beta cells crucial for regulating insulin sensitivity, secretion, and glucose metabolism. Also, we discuss the potential role played by ACE2 in aiding SARS-COV-2 entry into the pancreas and the possibility of ACE2 cooperation with alternative entry factors as well as how that may be linked to diabetes pathogenesis.
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Affiliation(s)
- Bushra Memon
- College of Health and Life Sciences Hamad Bin Khalifa University (HBKU)Qatar Foundation Doha Qatar
- Diabetes Research Center Qatar Biomedical Research Institute (QBRI)Hamad Bin KhalifaUniversity (HBKU)Qatar Foundation (QF) Doha Qatar
| | - Essam M. Abdelalim
- College of Health and Life Sciences Hamad Bin Khalifa University (HBKU)Qatar Foundation Doha Qatar
- Diabetes Research Center Qatar Biomedical Research Institute (QBRI)Hamad Bin KhalifaUniversity (HBKU)Qatar Foundation (QF) Doha Qatar
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4
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Xu H, An X, Tian J, Fu M, Wang Q, Li C, He X, Niu L. Angiotensin-(1-7) protects against sepsis-associated left ventricular dysfunction induced by lipopolysaccharide. Peptides 2021; 144:170612. [PMID: 34298021 DOI: 10.1016/j.peptides.2021.170612] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Revised: 07/11/2021] [Accepted: 07/16/2021] [Indexed: 12/12/2022]
Abstract
Sepsis-induced myocardial dysfunction is a major cause of death. The present study explored whether angiotensin (Ang)-(1-7), an important biologically active peptide of the renin-angiotensin system, could improve cardiac dysfunction and attenuate inflammation and apoptosis. Experiments were carried out in mice and in neonatal rat cardiomyocytes (NRCMs) treated with lipopolysaccharide (LPS) or Ang-(1-7). Angiotensin converting enzyme 2 (ACE2), Ang-(1-7) and Mas receptor (MasR) expressions were reduced in the mouse left ventricular and NRCM treated with LPS. Ang-(1-7) increased the ejection fraction and fractional shortening of left ventricular, which were reduced upon LPS injection in mice. Ang-(1-7) pre-treatment reversed LPS-induced decreases of α-myosin heavy chain (MHC) and β-MHC, and increases of S100 calcium binding protein A8 (S100A8) and S100A9 in the mouse left ventricular. The LPS-induced increases of tumor necrosis factor (TNF)-α and interleukin (IL)-1β in the mouse left ventricular and NRCMs were inhibited by Ang-(1-7) administration. Ang-(1-7) treatment reversed the increases of cleaved-caspase 3, cleaved-caspase 8 and Bax, and the decrease of Bcl2 induced by LPS in the mouse left ventricular and NRCMs. The increases of MAPKs pathway induced by LPS in NRCMs were inhibited by Ang-(1-7). These results indicate that Ang-(1-7) protects against sepsis-associated left ventricular dysfunction induced by LPS, and increases cardiac contractility via attenuating inflammation and apoptosis.
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Affiliation(s)
- Hui Xu
- Department of Cardiology, Xuzhou Children's Hospital of Xuzhou Medical University, Xuzhou, China
| | - Xinjiang An
- Department of Cardiology, Xuzhou Children's Hospital of Xuzhou Medical University, Xuzhou, China
| | - Jing Tian
- Department of Cardiology, Xuzhou Children's Hospital of Xuzhou Medical University, Xuzhou, China
| | - Mingyu Fu
- Department of Cardiology, Xuzhou Children's Hospital of Xuzhou Medical University, Xuzhou, China
| | - Qingwen Wang
- Department of Cardiology, Xuzhou Children's Hospital of Xuzhou Medical University, Xuzhou, China
| | - Chunli Li
- Department of Cardiology, Xuzhou Children's Hospital of Xuzhou Medical University, Xuzhou, China
| | - Xiuhua He
- Department of Cardiology, Xuzhou Children's Hospital of Xuzhou Medical University, Xuzhou, China
| | - Ling Niu
- Department of Cardiology, Xuzhou Children's Hospital of Xuzhou Medical University, Xuzhou, China.
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Berberine Reshapes the Balance of the Local Renin-Angiotensin System by Modulating Autophagy under Metabolic Stress in Pancreatic Islets. J Renin Angiotensin Aldosterone Syst 2021; 2021:9928986. [PMID: 34394712 PMCID: PMC8356011 DOI: 10.1155/2021/9928986] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2021] [Accepted: 04/09/2021] [Indexed: 01/22/2023] Open
Abstract
Results Prolonged exposure to palmitate increased the expression of ACE and AngII type 1 receptor (ATR1) and decreased the ACE2 expression, which was partly offset by berberine. In ob/ob mice, berberine increased in tolerance to glucose, improved abnormal β-cell and α-cell distributions, upregulated ACE2 expression, and decreased autophagosomes and the expression of LC3 and SQSTM1/p62. Autophagosomes and expression of LC3 and SQSTM1/p62 were increased in ACE2KO mice. Conclusions We demonstrated that berberine may improve the pancreatic islet function by regulating local RAS-mediated autophagy under metabolic stress.
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Li S, Zhao W, Tao Y, Liu C. Fugan Wan alleviates hepatic fibrosis by inhibiting ACE/Ang II/AT-1R signaling pathway and enhancing ACE2/Ang 1-7/Mas signaling pathway in hepatic fibrosis rat models. Am J Transl Res 2020; 12:592-601. [PMID: 32194907 PMCID: PMC7061829] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2019] [Accepted: 05/11/2019] [Indexed: 06/10/2023]
Abstract
Hepatic fibrosis is a repair and healing reaction for chronic injuries of liver. This study aimed to investigate protective effects of Fugan Wan (FGW) on hepatic fibrosis and clarify associated mechanisms. Hepatic fibrosis model was established by administrating dimethyl nitrosamine (DMN) to rats. Rats were divided into control, DMN and FGW groups. Haematoxylin and eosin (HE) staining was conducted to evaluate inflammatory response in hepatic fibrosis tissues. Sirius red staining was used to assess collagen disposition. Quantitative real-time PCR (qRT-PCR) was employed to detect antiotensin-converting enzyme homologue 2 (ACE2), Mas, transforming growth factor β1 (TGF-β1) mRNA. Western blot was used to examine collagen I, smooth muscle actin α (α-SMA), angiotensin type 1 receptor (AT-1R), extra-cellular regulated protein kinase (ERK), phosphorylated ERK (p-ERK), c-Jun and phosphorylated-c-Jun (p-c-Jun) expression. The results indicated that FGW significantly reduced inflammatory response of hepatic fibrosis tissues. FGW significantly decreased collagen deposition compared to that of DMN group (P < 0.01). FGW significantly down-regulated α-SMA expression compared to that of DMN group (P < 0.01). FGW significantly decreased AT-1R levels compared to that of DMN group (P < 0.01). Comparing with DMN group, ACE2 and Mas mRNA levels were significantly increased in FGW group (P < 0.01). FGW significantly down-regulated p-c-Jun and p-ERK1/2 compared to DMN group (P < 0.01). GFW significantly inhibited compared to DMN group (P < 0.01). In conclusion, FGW alleviated hepatic fibrosis by inhibiting ACE/Ang II/AT-1R signaling and enhancing ACE2/Ang 1-7/Mas signaling pathway in hepatic fibrosis rat models.
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Affiliation(s)
- Shu Li
- Department of Gastroenterology, Baoshan Branch, Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese MedicineShanghai 201900, China
- Institute of Liver Diseases, Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese MedicineShanghai 201203, China
| | - Wei Zhao
- Institute of Liver Diseases, Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese MedicineShanghai 201203, China
| | - Yanyan Tao
- Institute of Liver Diseases, Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese MedicineShanghai 201203, China
| | - Chenghai Liu
- Institute of Liver Diseases, Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese MedicineShanghai 201203, China
- Shanghai Key Laboratory of Traditional Chinese Clinical MedicineShanghai 201203, China
- Key Laboratory of Liver and Kidney Diseases, Ministry of EducationShanghai 201203, China
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Xu P, Guo H, Wang H, Lee SC, Liu M, Pan Y, Zheng J, Zheng K, Wang H, Xie Y, Bai X, Liu Y, Zhao M, Wang L. Downregulations of placental fatty acid transporters during cadmium-induced fetal growth restriction. Toxicology 2019; 423:112-122. [PMID: 31152847 DOI: 10.1016/j.tox.2019.05.013] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2018] [Revised: 04/01/2019] [Accepted: 05/27/2019] [Indexed: 01/22/2023]
Abstract
Cadmium (Cd) is one of the environmental pollutants, which has multiple toxic effects on fetuses and placentas. Placental fatty acid (FA) uptake and transport are critical for the fetal and placental development. We aimed to analyze the triglyceride (TG) level, the expression patterns of several key genes involved in FA uptake and transport, and the molecular mechanisms for the altered gene expressions in placentas in response to Cd treatment. Our results showed that the placental TG level was significantly decreased in the Cd-exposed placentas. Fatty acid transporting protein 1 (FATP1), FATP6 and fatty acid binding protein 3 (FABP3) were significantly down-regulated in the placentas from Cd-exposed mice. The expression level of phospho-p38 MAPK was increased by Cd treatment, while the protein level of total p38 MAPK remained unchanged. The expression levels of peroxisome proliferator-activated receptor-γ (PPAR-γ) and the hypoxia-inducible factor-1α (HIF-1α) were significantly decreased in the Cd-exposed placentas. The methylation levels of the promoter regions of FATP1, FATP6 and FABP3 showed no significant differences between the treatment and control groups. In addition, the circulating non-esterified fatty acid (NEFA), total cholesterol (TC), and TG levels were not decreased in the maternal serum from the Cd-exposed mice. Therefore, our results suggest Cd exposure dose not reduce the maternal FA supply, but reduces the placental TG level. Cd treatment also downregulates the placental expressions of FATP1, FATP6 and FABP3, respectively associated with p38-MAPK, p38 MAPK/PPAR-γ and HIF-1α pathways.
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Affiliation(s)
- Peng Xu
- School of Life Science, Shanxi University, Taiyuan 030006, China; Bio-X Institutes, Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders (Ministry of Education), Shanghai Jiao Tong University, Shanghai 200030, China.
| | - Huiqin Guo
- School of Life Science, Shanxi University, Taiyuan 030006, China.
| | - Huan Wang
- School of Life Science, Shanxi University, Taiyuan 030006, China.
| | - Shao Chin Lee
- School of Life Science, Shanxi University, Taiyuan 030006, China; School of Life Sciences, Jiangsu Normal University, Xuzhou 221116, China.
| | - Ming Liu
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China.
| | - Yongliang Pan
- Key Laboratory of Vector Biology and Pathogen Control of Zhejiang Province, School of Medicine, Huzhou University, Huzhou 313000, China.
| | - Jian Zheng
- Department of Cardiopulmonary Function Examination, Shanxi Provincial Cancer Hospital, Taiyuan 030013, China.
| | - Kang Zheng
- Special Ward, Shanxi Provincial Cancer Hospital, Taiyuan 030013, China.
| | - Huihui Wang
- School of Life Science, Shanxi University, Taiyuan 030006, China.
| | - Yuxin Xie
- School of Life Science, Shanxi University, Taiyuan 030006, China.
| | - Xiaoxia Bai
- Women's Hospital, School of Medicine, Zhejiang University, Hangzhou 310006, China.
| | - Yun Liu
- Department of Oncology, Fudan University Pudong Medical Center, Shanghai 201300, China.
| | - Meirong Zhao
- Key Laboratory of Microbial Technology for Industrial Pollution Control of Zhejiang Province, College of Environment, Zhejiang University of Technology, Hangzhou 310014, China.
| | - Lan Wang
- School of Life Science, Shanxi University, Taiyuan 030006, China.
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Descorbeth M, Figueroa K, Serrano-Illán M, De León M. Protective effect of docosahexaenoic acid on lipotoxicity-mediated cell death in Schwann cells: Implication of PI3K/AKT and mTORC2 pathways. Brain Behav 2018; 8:e01123. [PMID: 30264903 PMCID: PMC6236228 DOI: 10.1002/brb3.1123] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/21/2018] [Revised: 08/07/2018] [Accepted: 08/14/2018] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND AND AIM Docosahexaenoic acid (DHA) exhibits neuroprotective properties and has been shown to preserve nerve cells following trauma and ischemic injury. Recently, we showed that DHA pretreatment improved locomotion and reduced neuropathic pain after acute spinal cord injury in adult rats. These improvements were associated with an increase in the levels of AKT in spinal cord injury neurons. In this study, we investigate the implication of PI3K/AKT and mTOR pathway in DHA-mediated protection of primary cultured Schwann cells (pSC) undergoing palmitic acid-induced lipotoxicity (PA-LTx). METHODS Primary cultured Schwann cells were treated with PA (PA:BSA, 2:1) in the presence or absence of DHA (1-200 µM) for 24-48 hr. Cell viability was determined by crystal violet staining and nuclear morphology was examined using Hoechst staining. RESULTS We found that pSC cultures exposed to palmitic acid (PA) overload showed chromatin condensation, a decrease in cell viability and an inhibition of AKT phosphorylation in a time-dependent manner. Next, pSC exposed to PA overload were treated with DHA. The data show that co-treatment with DHA inhibited the loss of cell viability and apoptosis caused by PA. Moreover, treatment with DHA inhibited chromatin condensation, significantly stimulated p-AKT phosphorylation under PA-LTx condition, and DHA alone increased AKT phosphorylation. Additionally, when these pSC cultures were treated with PI3K inhibitors LY294002 and, BKM120 and mTOR inhibitors Torin 1 (mTORC1/mTORC2), but not rapamycin (mTORC1), the protective effects of DHA were not observed. CONCLUSION These findings suggest PI3K/AKT and mTORC2 kinase pathways are involved in the protective function (s) of DHA in PA-induced Schwann cell death.
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Affiliation(s)
- Magda Descorbeth
- Center for Health Disparities and Molecular Medicine and Department of Basic Sciences, Loma Linda University School of Medicine, Loma Linda, California
| | - Karen Figueroa
- Center for Health Disparities and Molecular Medicine and Department of Basic Sciences, Loma Linda University School of Medicine, Loma Linda, California
| | - Miguel Serrano-Illán
- Center for Health Disparities and Molecular Medicine and Department of Basic Sciences, Loma Linda University School of Medicine, Loma Linda, California
| | - Marino De León
- Center for Health Disparities and Molecular Medicine and Department of Basic Sciences, Loma Linda University School of Medicine, Loma Linda, California
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Wushenziye Formula Inhibits Pancreatic β Cell Apoptosis in Type 2 Diabetes Mellitus via MEK-ERK-Caspase-3 Signaling Pathway. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2018; 2018:4084259. [PMID: 30356368 PMCID: PMC6176308 DOI: 10.1155/2018/4084259] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/04/2018] [Revised: 07/30/2018] [Accepted: 08/30/2018] [Indexed: 01/09/2023]
Abstract
Background Wushenziye formula (WSZYF), composed of Radix Polygoni Multiflori Preparata, Mori fructus, Mori folium, and Cassiae semen, is effective in the treatment of type 2 diabetes mellitus (T2DM). Aim In this study, we aimed to explore the effects and the underlying mechanisms of WSZYF on inhibiting pancreatic β cell apoptosis and improving insulin resistance (IR) in T2DM. Methods A T2DM model was induced by Goto-Kakizaki diabetes prone rats. Cell apoptosis model was induced in MIN6 cells. Results In vivo, WSZYF decreased fasting blood glucose (FBG), insulin concentration, insulin resistance index, triglyceride (TG), total cholesterol (TC), and free fatty acids (FFA) in T2DM rats. Meanwhile, WSZYF ameliorated impairments in the morphology and structure of pancreatic tissues. In vitro, WSZYF enhanced cell viability and promoted insulin secretion in the apoptosis model of MIN6 cells. Furthermore, WSZYF modulated the expressions of apoptosis-related molecules by increasing the expressions of MEK1/2, p-MEK1/2, ERK1/2, and p-ERK1/2 and decreasing the cleaved-caspase-3 expression. Conclusion These findings indicate that WSZYF may become a new drug candidate in the treatment of T2DM and its antidiabetic mechanism is probably inhibiting pancreatic β cell apoptosis by modulating the MEK-ERK-Caspase-3 signaling pathway.
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10
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Xuan X, Gao F, Ma X, Huang C, Wang Y, Deng H, Wang S, Li W, Yuan L. Activation of ACE2/angiotensin (1-7) attenuates pancreatic β cell dedifferentiation in a high-fat-diet mouse model. Metabolism 2018; 81:83-96. [PMID: 29225087 DOI: 10.1016/j.metabol.2017.12.003] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/14/2017] [Revised: 11/14/2017] [Accepted: 12/03/2017] [Indexed: 12/12/2022]
Abstract
OBJECTIVE Angiotensin-converting enzyme 2 (ACE2) has been identified in pancreatic islets and can preserve β cells. In this study, we aimed to examine the possible role of ACE2 and its end product, angiotensin 1-7 (A1-7), in reducing β cell dedifferentiation during metabolic stress. METHODS First, a lineage-tracing experiment was performed to track β cells in mice fed a high-fat diet (HFD). Second, the ACE2/A1-7 axis was evaluated in the HFD mouse model. Intraperitoneal glucose tolerance tests (IPGTTs) and intraperitoneal insulin tolerance tests (IPITTs) were conducted. Phenotypic changes in β cells were detected by immunohistochemistry and quantitative real-time PCR. Pancreatic sections were immunostained for vascular endothelial growth factor (VEGF) and inducible nitric oxide synthase (iNOS). Finally, the effects of the ACE2/A1-7 axis were explored in isolated mouse islets exposed to different concentrations of glucose. Glucose-stimulated insulin release and levels of insulin mRNA and OCT4 mRNA were measured. RESULTS Pancreatic β cell dedifferentiation occurred both in vitro and in vivo in response to metabolic stress and was accompanied by ACE2 reduction. HFD-induced insulin resistance and glucose intolerance were exacerbated in ACE2-knockout (ACE2KO) mice but were alleviated by exogenous A1-7 in C57BL/6J mice. Approximately 20% of β cells were dedifferentiated in ACE2KO mice fed a standard rodent chow diet (SD). A higher percentage of dedifferentiated β cells was detected in ACE2KO mice than in wild-type (WT) mice under HFD conditions. In contrast, the administration of A1-7 alleviated HFD-induced β cell dedifferentiation in C57BL/6J mice. Moreover, the exogenous injection of A1-7 improved microcirculation in islets and decreased the production of iNOS in islets of C57BL/6J mice fed an HFD. Additionally, ACE2 was found to be mainly expressed in α cells of mice, while Mas, the receptor of A1-7, was distributed in β cells. CONCLUSIONS Overall, this study is the first to demonstrate that the ACE2/A1-7/Mas axis may be one of the intra-islet paracrine mechanisms of communication between α and β cells. Enhancing the ACE2/A1-7 axis exerts a protective effect by ameliorating β cell dedifferentiation, and this effect might be partially mediated through improvements in islet microcirculation and suppression of islet iNOS.
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Affiliation(s)
- Xiuping Xuan
- Department of Endocrinology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| | - Fei Gao
- Department of Orthopedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| | - Xiaoyi Ma
- Department of Endocrinology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| | - Chenghu Huang
- Department of Endocrinology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| | - Ying Wang
- Department of Endocrinology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| | - Hongjun Deng
- Department of Endocrinology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| | - Shiqi Wang
- Department of Endocrinology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| | - Wencun Li
- Department of Endocrinology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| | - Li Yuan
- Department of Endocrinology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China.
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11
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Wang Y, Wang G, Cui L, Liu R, Xiao H, Yin C. Angiotensin 1-7 ameliorates caerulein-induced inflammation in pancreatic acinar cells by downregulating Toll-like receptor 4/nuclear factor-κB expression. Mol Med Rep 2017; 17:3511-3518. [PMID: 29286117 PMCID: PMC5802148 DOI: 10.3892/mmr.2017.8354] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2017] [Accepted: 09/11/2017] [Indexed: 12/11/2022] Open
Abstract
The present study aimed to investigate the effects of angiotensin (Ang) 1–7 on caerulein (CAE)-stimulated nuclear factor (NF)-κB, Toll-like receptor (TLR4) and cytokine expression using pancreatic acinar AR42J cells. AR42J cells were treated with 10 nmol/l CAE for various durations. In addition, cells were pretreated with various concentrations of Ang 1–7 or A779, a specific antagonist of Ang 1–7, and were stimulated with CAE for 12 h. Control cells were treated with vehicle (F-12K complete medium with 2% fetal bovine serum, 10 U/ml penicillin and 100 mg/ml streptomycin) alone. The mRNA and protein expression levels of TLR4, NF-κB, interleukin (IL)-6, IL-8, IL-10 and tumor necrosis factor-α (TNF-α) were determined by western blotting, immunofluorescence and reverse transcription-quantitative polymerase chain reaction. CAE treatment stimulated TLR4 and NF-κB expression within AR42J cells. Immunofluorescence indicated that TLR4 was expressed on the membranes and in the cytoplasm of AR42J cells, whereas NF-κB expression accumulated in the cytoplasm and nuclei. CAE-induced expression of TLR4 and NF-κB within AR42J cells was abrogated by 10−5 mmol/l Ang 1–7; however, TLR4 and NF-κB expression was enhanced with the addition of A779, particularly 10−5 mmol/l. In addition, treatment with 10−6 and 10−5 mmol/l Ang 1–7 significantly mitigated CAE-induced expression of IL-6, IL-8 and TNF-α, whereas it enhanced IL-10 expression. Conversely, A779 treatment enhanced the CAE-induced expression of IL-6, IL-8 and TNF-α, and reduced IL-10 expression in AR42J cells. In conclusion, these results suggested that Ang 1–7 may attenuate CAE-induced inflammation by downregulating TLR4, NF-κB and proinflammatory cytokine expression within AR42J cells. Therefore, Ang 1–7 may exert protective effects against the pathological progression of AP in a cell model of AP induced by CAE and may be considered in the development of treatments for this disease.
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Affiliation(s)
- Yan Wang
- Department of Emergency, Beijing Friendship Hospital, Beijing 100050, P.R. China
| | - Guoxing Wang
- Department of Emergency, Beijing Friendship Hospital, Beijing 100050, P.R. China
| | - Lijian Cui
- Department of Emergency, Beijing Chao‑Yang Hospital, Beijing 100020, P.R. China
| | - Ruixia Liu
- Department of Internal Medicine, Beijing Obstetrics and Gynecology Hospital, Capital Medical University, Beijing 100026, P.R. China
| | - Hongli Xiao
- Department of Emergency, Beijing Friendship Hospital, Beijing 100050, P.R. China
| | - Chenghong Yin
- Department of Internal Medicine, Beijing Obstetrics and Gynecology Hospital, Capital Medical University, Beijing 100026, P.R. China
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Hogan MF, Hull RL. The islet endothelial cell: a novel contributor to beta cell secretory dysfunction in diabetes. Diabetologia 2017; 60:952-959. [PMID: 28396983 PMCID: PMC5505567 DOI: 10.1007/s00125-017-4272-9] [Citation(s) in RCA: 75] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/03/2017] [Accepted: 03/02/2017] [Indexed: 11/25/2022]
Abstract
The pancreatic islet is highly vascularised, with an extensive capillary network. In addition to providing nutrients and oxygen to islet endocrine cells and transporting hormones to the peripheral circulation, islet capillaries (comprised primarily of islet endothelial cells) are an important source of signals that enhance survival and function of the islet beta cell. In type 2 diabetes, and animal models thereof, evidence exists of morphological and functional abnormalities in these islet endothelial cells. In diabetes, islet capillaries are thickened, dilated and fragmented, and islet endothelial cells express markers of inflammation and activation. In vitro data suggest that this dysfunctional islet endothelial phenotype may contribute to impaired insulin release from the beta cell. This review examines potential candidate molecules that may mediate the positive effects of islet endothelial cells on beta cell survival and function under normal conditions. Further, it explores possible mechanisms underlying the development of islet endothelial dysfunction in diabetes and reviews therapeutic options for ameliorating this aspect of the islet lesion in type 2 diabetes. Finally, considerations regarding differences between human and rodent islet vasculature and the potentially unforeseen negative consequences of strategies to expand the islet vasculature, particularly under diabetic conditions, are discussed.
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Affiliation(s)
- Meghan F Hogan
- Division of Metabolism, Endocrinology and Nutrition, VA Puget Sound Health Care System (151), 1660 South Columbian Way, Seattle, WA, 98108, USA
- Department of Medicine, University of Washington, Seattle, WA, USA
| | - Rebecca L Hull
- Division of Metabolism, Endocrinology and Nutrition, VA Puget Sound Health Care System (151), 1660 South Columbian Way, Seattle, WA, 98108, USA.
- Department of Medicine, University of Washington, Seattle, WA, USA.
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Lin XL, Liu Y, Liu M, Hu H, Pan Y, Fan XJ, Hu XM, Zou WW. Inhibition of Hydrogen Peroxide-Induced Human Umbilical Vein Endothelial Cells Aging by Allicin Depends on Sirtuin1 Activation. Med Sci Monit 2017; 23:563-570. [PMID: 28139552 PMCID: PMC5297325 DOI: 10.12659/msm.899730] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2016] [Accepted: 06/22/2016] [Indexed: 11/09/2022] Open
Abstract
BACKGROUND The abnormal activity of Sirtuin 1 (Sirt1) is closely related to the aging of vascular endothelial cells. As a bioactive molecule, allicin has antioxidant, anti-inflammatory, and lipid-regulating mechanisms. However, few reports about the relationship of allicin and Sirt1 have been published. In this study, we aimed to elucidate the effect of allicin on Human Umbilical Vein Endothelial Cells (HUVECs) aging induced by hydrogen peroxide (H2O2) and the role of Sirt1 in this phenomenon. MATERIAL AND METHODS HUVEC were exposed to H2O2 to establish the aging model. The expression of protein and RNA were detected by Western blot and Reverse transcription-quantitative polymerase chain reaction. The 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was used to assess cell viability. Sirt1 enzyme activity assay was used to analyze enzymatic activity. Reactive oxygen species was detected by dichlorofluorescein diacetate (DCFH-DA). Cell aging was detected by Senescence β-Galactosidase (SA-β-gal) staining. RESULTS Results of this study revealed that pretreating HUVECs with 5 ng/mL allicin before exposure to H2O2 resulted in increased cell viability and reduced reactive oxygen species generation. Western blot and quantitative real-time polymerase chain reaction (qRT-PCR) analysis showed that H2O2 attenuated the phosphorylation and activation of Sirt1 and increased the expression of plasminogen activator inhibitor-1(PAI-1) protein. Moreover, H2O2 also promoted HUVEC aging. These effects were significantly alleviated by 5 ng/mL allicin co-treatment. Furthermore, the anti-aging effects of allicin were abolished by the Sirt1 inhibitor nicotinamide (NAM). CONCLUSIONS Overall, the results demonstrated that allicin protects HUVECs from H2O2-induced oxidative stress and aging via the activation of Sirt1.
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Affiliation(s)
- Xiao-Long Lin
- Department of Pathology, Affiliated Hui Zhou hospital (The Third People’s Hospital of Huizhou), Guangzhou Medical University, Huizhou, Guangdong, P.R. China
| | - Yuanbo Liu
- Medical Department of Neurology, The Sixth People’s Hospital of Huizhou (The People’s Hospital of Huiyang), Huizhou, Guangdong, P.R. China
| | - Mihua Liu
- Department of Clinical Laboratory, Affiliated Nanhua Hospital, University of South China, Hengyang, Hunan, P.R. China
| | - Huijun Hu
- Department of Pathology, Affiliated Hui Zhou hospital (The Third People’s Hospital of Huizhou), Guangzhou Medical University, Huizhou, Guangdong, P.R. China
| | - Yongquan Pan
- Department of Pathology, Affiliated Hui Zhou hospital (The Third People’s Hospital of Huizhou), Guangzhou Medical University, Huizhou, Guangdong, P.R. China
| | - Xiao-Juan Fan
- Department of Pathology, Affiliated Hui Zhou hospital (The Third People’s Hospital of Huizhou), Guangzhou Medical University, Huizhou, Guangdong, P.R. China
| | - Xue-Mei Hu
- Department of Pathology, Affiliated Hui Zhou hospital (The Third People’s Hospital of Huizhou), Guangzhou Medical University, Huizhou, Guangdong, P.R. China
| | - Wei-Wen Zou
- Department of Pathology, Affiliated Hui Zhou hospital (The Third People’s Hospital of Huizhou), Guangzhou Medical University, Huizhou, Guangdong, P.R. China
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Fedson DS. Treating the host response to emerging virus diseases: lessons learned from sepsis, pneumonia, influenza and Ebola. ANNALS OF TRANSLATIONAL MEDICINE 2016; 4:421. [PMID: 27942512 DOI: 10.21037/atm.2016.11.03] [Citation(s) in RCA: 91] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
There is an ongoing threat of epidemic or pandemic diseases that could be caused by influenza, Ebola or other emerging viruses. It will be difficult and costly to develop new drugs that target each of these viruses. Statins and angiotensin receptor blockers (ARBs) have been effective in treating patients with sepsis, pneumonia and influenza, and a statin/ARB combination appeared to dramatically reduce mortality during the recent Ebola outbreak. These drugs target (among other things) the endothelial dysfunction found in all of these diseases. Most scientists work on new drugs that target viruses, and few accept the idea of treating the host response with generic drugs. A great deal of research will be needed to show conclusively that these drugs work, and this will require the support of public agencies and foundations. Investigators in developing countries should take an active role in this research. If the next Public Health Emergency of International Concern is caused by an emerging virus, a "top down" approach to developing specific new drug treatments is unlikely to be effective. However, a "bottom up" approach to treatment that targets the host response to these viruses by using widely available and inexpensive generic drugs could reduce mortality in any country with a basic health care system. In doing so, it would make an immeasurable contribution to global equity and global security.
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Affiliation(s)
- David S Fedson
- Formerly, Department of Medicine, University of Virginia School of Medicine, Charlottesville, Virginia, USA
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15
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The Potential Protective Action of Vitamin D in Hepatic Insulin Resistance and Pancreatic Islet Dysfunction in Type 2 Diabetes Mellitus. Nutrients 2016; 8:147. [PMID: 26959059 PMCID: PMC4808876 DOI: 10.3390/nu8030147] [Citation(s) in RCA: 77] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2015] [Revised: 02/26/2016] [Accepted: 02/29/2016] [Indexed: 02/06/2023] Open
Abstract
Vitamin D deficiency (i.e., hypovitaminosis D) is associated with increased insulin resistance, impaired insulin secretion, and poorly controlled glucose homeostasis, and thus is correlated with the risk of metabolic diseases, including type 2 diabetes mellitus (T2DM). The liver plays key roles in glucose and lipid metabolism, and its dysregulation leads to abnormalities in hepatic glucose output and triglyceride accumulation. Meanwhile, the pancreatic islets are constituted in large part by insulin-secreting β cells. Consequently, islet dysfunction, such as occurs in T2DM, produces hyperglycemia. In this review, we provide a critical appraisal of the modulatory actions of vitamin D in hepatic insulin sensitivity and islet insulin secretion, and we discuss the potential roles of a local vitamin D signaling in regulating hepatic and pancreatic islet functions. This information provides a scientific basis for establishing the benefits of the maintenance, or dietary manipulation, of adequate vitamin D status in the prevention and management of obesity-induced T2DM and non-alcoholic fatty liver disease.
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Lee HJ, Choi JS, Lee HJ, Kim WH, Park SI, Song J. Effect of excess iron on oxidative stress and gluconeogenesis through hepcidin during mitochondrial dysfunction. J Nutr Biochem 2015; 26:1414-23. [DOI: 10.1016/j.jnutbio.2015.07.008] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2014] [Revised: 06/19/2015] [Accepted: 07/14/2015] [Indexed: 02/06/2023]
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17
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Xiao X, Zhang C, Ma X, Miao H, Wang J, Liu L, Chen S, Zeng R, Chen Y, Bihl JC. Angiotensin-(1-7) counteracts angiotensin II-induced dysfunction in cerebral endothelial cells via modulating Nox2/ROS and PI3K/NO pathways. Exp Cell Res 2015; 336:58-65. [PMID: 26101159 DOI: 10.1016/j.yexcr.2015.06.010] [Citation(s) in RCA: 59] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2015] [Revised: 06/15/2015] [Accepted: 06/16/2015] [Indexed: 11/29/2022]
Abstract
Angiotensin (Ang) II, the main effector of the renin-angiotensin system, has been implicated in the pathogenesis of vascular diseases. Ang-(1-7) binds to the G protein-coupled Mas receptor (MasR) and can exert vasoprotective effects. We investigated the effects and underlying mechanisms of Ang-(1-7) on Ang II-induced dysfunction and oxidative stress in human brain microvascular endothelial cells (HbmECs). The pro-apoptotic activity, reactive oxygen species (ROS) and nitric oxide (NO) productions in HbmECs were measured. The protein expressions of nicotinamide adenine dinucleotide phosphate oxidase 2 (Nox2), serine/threonine kinase (Akt), endothelial nitric oxide synthase (eNOS) and their phosphorylated forms (p-Akt and p-eNOS) were examined by western blot. MasR antagonist and phosphatidylinositol-3-kinase (PI3K) inhibitor were used for receptor/pathway verification. We found that Ang-(1-7) suppressed Ang II-induced pro-apoptotic activity, ROS over-production and NO reduction in HbmECs, which were abolished by MasR antagonist. In addition, Ang-(1-7) down-regulated the expression of Nox2, and up-regulated the ratios of p-Akt/Akt and its downstream p-eNOS/eNOS in HbmECs. Exposure to PI3K inhibitor partially abrogated Ang-(1-7)-mediated protective effects in HbmECs. Our data suggests that Ang-(1-7)/MasR axis protects HbmECs from Ang II-induced dysfunction and oxidative stress via inhibition of Nox2/ROS and activation of PI3K/NO pathways.
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Affiliation(s)
- Xiang Xiao
- Department of Pharmacology & Toxicology, Boonshoft School of Medicine, Wright State University, Dayton, OH 45435, USA
| | - Cheng Zhang
- Department of Pharmacology & Toxicology, Boonshoft School of Medicine, Wright State University, Dayton, OH 45435, USA
| | - Xiaotang Ma
- Institute of Neurology, Affiliated Hospital of Guangdong Medical College, Zhanjiang, Guangdong 524001, China
| | - Huilai Miao
- Department of Surgery, Affiliated Hospital of Guangdong Medical College, Zhanjiang, Guangdong 524001, China
| | - Jinju Wang
- Department of Pharmacology & Toxicology, Boonshoft School of Medicine, Wright State University, Dayton, OH 45435, USA
| | - Langni Liu
- Department of Pharmacology & Toxicology, Boonshoft School of Medicine, Wright State University, Dayton, OH 45435, USA
| | - Shuzhen Chen
- Department of Pharmacology & Toxicology, Boonshoft School of Medicine, Wright State University, Dayton, OH 45435, USA
| | - Rong Zeng
- Department of Surgery, Affiliated Hospital of Guangdong Medical College, Zhanjiang, Guangdong 524001, China
| | - Yanfang Chen
- Department of Pharmacology & Toxicology, Boonshoft School of Medicine, Wright State University, Dayton, OH 45435, USA.
| | - Ji C Bihl
- Department of Pharmacology & Toxicology, Boonshoft School of Medicine, Wright State University, Dayton, OH 45435, USA; Institute of Neurology, Affiliated Hospital of Guangdong Medical College, Zhanjiang, Guangdong 524001, China.
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Huang C, Yuan L, Cao S. Endogenous GLP-1 as a key self-defense molecule against lipotoxicity in pancreatic islets. Int J Mol Med 2015; 36:173-85. [PMID: 25976560 PMCID: PMC4494597 DOI: 10.3892/ijmm.2015.2207] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2015] [Accepted: 05/07/2015] [Indexed: 01/15/2023] Open
Abstract
The number of pro-α cells is known to increase in response to β cell injury and these cells then generate glucagon-like peptide-1 (GLP-1), thus attenuating the development of diabetes. The aim of the present study was to further examine the role and the mechanisms responsible for intra-islet GLP-1 production as a self-protective response against lipotoxicity. The levels of the key enzyme, prohormone convertase 1/3 (PC1/3), as well as the synthesis and release of GLP-1 in models of lipotoxicity were measured. Furthermore, islet viability, apoptosis, oxidative stress and inflammation, as well as islet structure were assessed after altering GLP-1 receptor signaling. Both prolonged exposure to palmitate and a high-fat diet facilitated PC1/3 expression, as well as the synthesis and release of GLP-1 induced by β cell injury and the generation of pro-α cells. Prolonged exposure to palmitate increased reactive oxygen species (ROS) production, and the antioxidant, N-acetylcysteine (NAC), partially prevented the detrimental effects induced by palmitate on β cells, resulting in decreased GLP-1 levels. Furthermore, the inhibition of GLP-1 receptor (GLP-1R) signaling by treatment with exendin‑(9-39) further decreased cell viability, increased cell apoptosis and caused a stronger inhibition of the β cell-specific transcription factor, pancreatic duodenal homeobox 1 (PDX1). Moreover, treatment with the GLP-1R agonist, liraglutide, normalized islet structure and function, resulting in a decrease in cell death and in the amelioration of β cell marker expression. Importantly, liraglutide maintained the oxidative balance and decreased inflammatory factor and p65 expression. Overall, our data demonstrate that an increase in the number of pro-α cells and the activation of the intra-islet GLP-1 system comprise a self-defense mechanism for enhancing β cell survival to combat lipid overload, which is in part mediated by oxidative stress and inflammation.
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Affiliation(s)
- Chenghu Huang
- Department of Endocrinology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430022, P.R. China
| | - Li Yuan
- Department of Endocrinology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430022, P.R. China
| | - Shuyi Cao
- Department of Endocrinology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430022, P.R. China
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Zhang XF, Choi YJ, Han JW, Kim E, Park JH, Gurunathan S, Kim JH. Differential nanoreprotoxicity of silver nanoparticles in male somatic cells and spermatogonial stem cells. Int J Nanomedicine 2015; 10:1335-57. [PMID: 25733828 PMCID: PMC4337509 DOI: 10.2147/ijn.s76062] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Background Silver nanoparticles (AgNPs) possess unique physical, chemical, and biological properties. AgNPs have been increasingly used as anticancer, antiangiogenic, and antibacterial agents for the treatment of bacterial infections in open wounds as well as in ointments, bandages, and wound dressings. The present study aimed to investigate the effects of two different sizes of AgNPs (10 nm and 20 nm) in male somatic Leydig (TM3) and Sertoli (TM4) cells and spermatogonial stem cells (SSCs). Methods Here, we demonstrate a green and simple method for the synthesis of AgNPs using Bacillus cereus culture supernatants. The synthesized AgNPs were characterized using ultraviolet and visible absorption spectroscopy, X-ray diffraction, Fourier transform infrared spectroscopy, and transmission electron microscopy (TEM). The toxicity of the synthesized AgNPs was evaluated by the effects on cell viability, metabolic activity, oxidative stress, apoptosis, and expression of genes encoding steroidogenic and tight junction proteins. Results AgNPs inhibited the viability and proliferation of TM3 and TM4 cells in a dose- and size-dependent manner by damaging cell membranes and inducing the generation of reactive oxygen species, which in turn affected SSC growth on TM3 and TM4 as feeder cells. Small AgNPs (10 nm) were more cytotoxic than medium-sized nanoparticles (20 nm). TEM revealed the presence of AgNPs in the cell cytoplasm and nucleus, and detected mitochondrial damage and enhanced formation of autosomes and autolysosomes in the AgNP-treated cells. Flow cytometry analysis using Annexin V/propidium iodide staining showed massive cell death by apoptosis or necrosis. Real-time polymerase chain reaction and western blot analyses indicated that in TM3 and TM4 cells, AgNPs activated the p53, p38, and pErk1/2 signaling pathways and significantly downregulated the expression of genes related to testosterone synthesis (TM3) and tight junctions (TM4). Furthermore, the exposure of TM3 and TM4 cells to AgNPs inhibited proliferation and self-renewal of SSCs. Conclusion Our results suggest that AgNPs exhibit size-dependent nanoreprotoxicity in male somatic cells and SSCs, strongly suggesting that applications of AgNPs in commercial products must be carefully evaluated. Further studies of AgNPs-induced nanoreprotoxicity in animal models are required.
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Affiliation(s)
- Xi-Feng Zhang
- Department of Animal Biotechnology, Konkuk University, Seoul, South Korea
| | - Yun-Jung Choi
- Department of Animal Biotechnology, Konkuk University, Seoul, South Korea
| | - Jae Woong Han
- Department of Animal Biotechnology, Konkuk University, Seoul, South Korea
| | - Eunsu Kim
- Department of Animal Biotechnology, Konkuk University, Seoul, South Korea
| | - Jung Hyun Park
- Department of Animal Biotechnology, Konkuk University, Seoul, South Korea
| | | | - Jin-Hoi Kim
- Department of Animal Biotechnology, Konkuk University, Seoul, South Korea
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