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Uryash A, Mijares A, Estève E, Adams JA, Lopez JR. Smooth Muscle Cells of Dystrophic (mdx) Mice Are More Susceptible to Hypoxia; The Protective Effect of Reducing Ca 2+ Influx. Biomedicines 2023; 11:biomedicines11020623. [PMID: 36831159 PMCID: PMC9953629 DOI: 10.3390/biomedicines11020623] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2023] [Revised: 02/13/2023] [Accepted: 02/17/2023] [Indexed: 02/22/2023] Open
Abstract
Duchenne muscular dystrophy (DMD) is an inherited muscular disorder caused by mutations in the dystrophin gene. DMD patients have hypoxemic events due to sleep-disordered breathing. We reported an anomalous regulation of resting intracellular Ca2+ ([Ca2+]i) in vascular smooth muscle cells (VSMCs) from a mouse (mdx) model of DMD. We investigated the effect of hypoxia on [Ca2+]i in isolated and quiescent VSMCs from C57BL/10SnJ (WT) and C57BL/10ScSn-Dmd (mdx) male mice. [Ca2+]i was measured using Ca2+-selective microelectrodes under normoxic conditions (95% air, 5% CO2) and after hypoxia (glucose-free solution aerated with 95% N2-5% CO2 for 30 min). [Ca2+]i in mdx VSMCs was significantly elevated compared to WT under normoxia. Hypoxia-induced [Ca2+]i overload, which was significantly greater in mdx than in WT VSMCs. A low Ca2+ solution caused a reduction in [Ca2+]i and prevented [Ca2+]i overload secondary to hypoxia. Nifedipine (10 µM), a Ca2+ channel blocker, did not modify resting [Ca2+]i in VSMCs but partially prevented the hypoxia-induced elevation of [Ca2+]i in both genotypes. SAR7334 (1 µM), an antagonist of TRPC3 and TRPC6, reduced the basal and [Ca2+]i overload caused by hypoxia. Cell viability, assessed by tetrazolium salt (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, was significantly reduced in mdx compared to WT VSMCs. Pretreatment with SAR7341 increases cell viability in normoxic mdx (p < 0.001) and during hypoxia in WT and mdx VSMCs. These results provide evidence that the lack of dystrophin makes VSMCs more susceptible to hypoxia-induced [Ca2+]i overload, which appears to be mediated by increased Ca2+ entry through L-type Ca2+ and TRPC channels.
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Affiliation(s)
- Arkady Uryash
- Division of Neonatology, Mount Sinai Medical Center, Miami, FL 33140, USA
| | - Alfredo Mijares
- Centro de Biofísica y Bioquímica, Instituto Venezolano de Investigaciones Científicas, Caracas 21827, Venezuela
| | - Eric Estève
- PhyMedExp, University of Montpellier, CNRS, INSERM, CHRU Montpellier, 34090 Montpellier, France
- Univ. Grenoble Alpes, CNRS, TIMC-IMAG/PRETA (UMR 5525), 38000 Grenoble, France
| | - Jose A. Adams
- Division of Neonatology, Mount Sinai Medical Center, Miami, FL 33140, USA
| | - Jose R. Lopez
- Department of Research, Mount Sinai Medical Center, Miami Beach, FL 33140, USA
- Correspondence: ; Tel.: +1-305-674-2727
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Niu X, Yu J, Huang Q, Yu J, Yang Y, Song H, Liu Y, Xiao X, Cui L, Li W. Immunoenhancement activity of Bletilla striata polysaccharide through MAPK and NF-κB signalling pathways in vivo and in vitro. Autoimmunity 2022; 55:650-660. [PMID: 35892187 DOI: 10.1080/08916934.2022.2103801] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Bletilla striata (Thunb.) Reichb.f., is a traditional Chinese medicine, and the Bletilla striata polysaccharide (BSP) is one of the principal components extracted from Bletilla striata with various biological activities. Previous studies have shown that many natural polysaccharides have significant immunomodulatory activities. However, as a plant polysaccharide, the research of BSP on immunomodulatory activities is limited. In this study, we aim to investigate the immunomodulatory effect of BSP in vivo and further explore its underlying mechanism in vitro. In vivo, a cyclophosphamide (CTX)-induced immunosuppression mice mode was established by intraperitoneal injection of CTX, and the immune-enhancing effect of BSP (25, 50 and 100 mg/kg) on immunosuppressed mice were evaluated. The result indicated that BSP could significantly improve the immune organ index and the content of immunoglobulin, TNF-α and IL-4 in serum. It was also found that BSP could clearly ameliorate the spleen damage induced by CTX. Meanwhile, the result showed that BSP could not only improve the proliferation of splenocytes, but also activate the lactate dehydrogenase (LDH) and acid phosphatase (ACP) in mouse spleen tissue. In vitro, potential mechanism was further revealed in macrophages. The result supported that BSP could activate macrophages with high phagocytic ability, and induce macrophages to secrete cytokines. Finally, it revealed that activation of NF-κB and MAPK signalling pathway should be the underlying mechanism of the immunoenhancment of BSP.
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Affiliation(s)
- Xiaofeng Niu
- School of Pharmacy, Xi'an Jiaotong University, Xi'an, PR China
| | - Jiabao Yu
- School of Pharmacy, Xi'an Jiaotong University, Xi'an, PR China
| | - Qiuxia Huang
- School of Pharmacy, Xi'an Jiaotong University, Xi'an, PR China
| | - Jinjin Yu
- School of Pharmacy, Xi'an Jiaotong University, Xi'an, PR China
| | - Yajie Yang
- School of Pharmacy, Xi'an Jiaotong University, Xi'an, PR China
| | - Huixin Song
- School of Pharmacy, Xi'an Jiaotong University, Xi'an, PR China
| | - Yang Liu
- School of Pharmacy, Xi'an Jiaotong University, Xi'an, PR China
| | - Xin Xiao
- School of Pharmacy, Xi'an Jiaotong University, Xi'an, PR China
| | - Langjun Cui
- School of Life Sciences, Shaanxi Normal University, Xi'an, PR China
| | - Weifeng Li
- School of Pharmacy, Xi'an Jiaotong University, Xi'an, PR China
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The Multistage Antimalarial Compound Calxinin Perturbates P. falciparum Ca2+ Homeostasis by Targeting a Unique Ion Channel. Pharmaceutics 2022; 14:pharmaceutics14071371. [PMID: 35890267 PMCID: PMC9319510 DOI: 10.3390/pharmaceutics14071371] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2022] [Revised: 05/30/2022] [Accepted: 06/07/2022] [Indexed: 12/22/2022] Open
Abstract
Malaria elimination urgently needs novel antimalarial therapies that transcend resistance, toxicity, and high costs. Our multicentric international collaborative team focuses on developing multistage antimalarials that exhibit novel mechanisms of action. Here, we describe the design, synthesis, and evaluation of a novel multistage antimalarial compound, ‘Calxinin’. A compound that consists of hydroxyethylamine (HEA) and trifluoromethyl-benzyl-piperazine. Calxinin exhibits potent inhibitory activity in the nanomolar range against the asexual blood stages of drug-sensitive (3D7), multidrug-resistant (Dd2), artemisinin-resistant (IPC4912), and fresh Kenyan field isolated Plasmodium falciparum strains. Calxinin treatment resulted in diminished maturation of parasite sexual precursor cells (gametocytes) accompanied by distorted parasite morphology. Further, in vitro liver-stage testing with a mouse model showed reduced parasite load at an IC50 of 79 nM. A single dose (10 mg/kg) of Calxinin resulted in a 30% reduction in parasitemia in mice infected with a chloroquine-resistant strain of the rodent parasite P. berghei. The ex vivo ookinete inhibitory concentration within mosquito gut IC50 was 150 nM. Cellular in vitro toxicity assays in the primary and immortalized human cell lines did not show cytotoxicity. A computational protein target identification pipeline identified a putative P. falciparum membrane protein (Pf3D7_1313500) involved in parasite calcium (Ca2+) homeostasis as a potential Calxinin target. This highly conserved protein is related to the family of transient receptor potential cation channels (TRP-ML). Target validation experiments showed that exposure of parasitized RBCs (pRBCs) to Calxinin induces a rapid release of intracellular Ca2+ from pRBCs; leaving de-calcinated parasites trapped in RBCs. Overall, we demonstrated that Calxinin is a promising antimalarial lead compound with a novel mechanism of action and with potential therapeutic, prophylactic, and transmission-blocking properties against parasites resistant to current antimalarials.
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Bao M, Huang W, Zhao Y, Fang X, Zhang Y, Gao F, Huang D, Wang B, Shi G. Verapamil Alleviates Myocardial Ischemia/Reperfusion Injury by Attenuating Oxidative Stress via Activation of SIRT1. Front Pharmacol 2022; 13:822640. [PMID: 35281891 PMCID: PMC8905444 DOI: 10.3389/fphar.2022.822640] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2021] [Accepted: 01/21/2022] [Indexed: 02/05/2023] Open
Abstract
Myocardial ischemia/reperfusion (I/R) injury is a potential complication of ischemic heart disease after recanalization. One of the primary reasons for I/R injury is the excessive accumulation of reactive oxygen species (ROS) in cardiomyocytes. Verapamil, a classic calcium channel blocker, has the potential to mitigate I/R-evoked oxidative stress. However, the underlying mechanisms have not been fully elucidated. SIRT1 is an essential regulator of I/R and offers resistance to oxidative stress arising from I/R. It is still inconclusive if verapamil can reduce myocardial I/R-triggered oxidative damage through modulating SIRT1 antioxidant signaling. To verify our hypothesis, the H9c2 cardiomyocytes and the mice were treated with verapamil and then exposed to hypoxia/reoxygenation (H/R) or I/R in the presence or absence of the SIRT1 inhibitor EX527. As expected, verapamil stimulated SIRT1 antioxidant signaling evidenced by upregulation of SIRT1, FoxO1, SOD2 expressions and downregulation of Ac-FoxO1 expression in vitro and in vivo. In addition, verapamil remarkably suppressed H/R and I/R-induced oxidative stress proven by declined ROS level and MDA content. The cardioprotective actions of verapamil via SIRT1 were further confirmed in the experiments with the presence of the specific SIRT1 inhibitor EX527. We demonstrated that verapamil alleviated myocardial I/R-evoked oxidative stress partially via activation of SIRT1 antioxidant signaling. Subsequently, verapamil protected against cardiac dysfunction and myocardial infarction accompanied by oxidative stress.
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Affiliation(s)
- Mi Bao
- Department of Pharmacology, Shantou University Medical College, Shantou, China
| | - Weiyi Huang
- Department of Clinical Pharmacy, Shantou University Medical College, Shantou, China
- Pharmaceutical Laboratory, The First Affiliated Hospital, Shantou University Medical College, Shantou, China
| | - Yang Zhao
- Department of Pharmacology, Shantou University Medical College, Shantou, China
| | - Xinzhe Fang
- Department of Pharmacology, Shantou University Medical College, Shantou, China
| | - Yanmei Zhang
- Department of Pharmacology, Shantou University Medical College, Shantou, China
- Pharmaceutical Laboratory, The First Affiliated Hospital, Shantou University Medical College, Shantou, China
| | - Fenfei Gao
- Department of Pharmacology, Shantou University Medical College, Shantou, China
- Pharmaceutical Laboratory, The First Affiliated Hospital, Shantou University Medical College, Shantou, China
| | - Danmei Huang
- Department of Pharmacology, Shantou University Medical College, Shantou, China
- Pharmaceutical Laboratory, The First Affiliated Hospital, Shantou University Medical College, Shantou, China
| | - Bin Wang
- Department of Pharmacology, Shantou University Medical College, Shantou, China
- Pharmaceutical Laboratory, The First Affiliated Hospital, Shantou University Medical College, Shantou, China
| | - Ganggang Shi
- Department of Pharmacology, Shantou University Medical College, Shantou, China
- Pharmaceutical Laboratory, The First Affiliated Hospital, Shantou University Medical College, Shantou, China
- Department of Cardiovascular Diseases, The First Affiliated Hospital, Shantou University Medical College, Shantou, China
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Xian S, Zeng Z. Signalling pathways implicated in the pathogenesis of rheumatic heart disease (Review). Exp Ther Med 2020; 21:76. [PMID: 33365076 PMCID: PMC7716644 DOI: 10.3892/etm.2020.9508] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Accepted: 10/28/2020] [Indexed: 12/14/2022] Open
Abstract
Rheumatic heart disease (RHD) is frequently encountered in underdeveloped areas and primarily affects patients under the age of 40 years old. The pathogenesis of RHD has yet to be fully elucidated and surgical treatment remains the only option, which is expensive and technically demanding for patients in less developed areas. Signalling pathways are crucial for the occurrence and development of several diseases, and researchers worldwide have made progress in elucidating the signalling pathways associated with the pathogenesis of RHD. The aim of the present review was to discuss 6 signalling pathways implicated in the pathogenesis of RHD, summarize the methods and progress of these studies and propose future research directions. Important information on the pathogenesis of RHD according to the current progress of signalling pathway studies was also summarized, in the hope that this review may serve as a reference for future research on the signalling pathways involved in the pathogenesis of RHD.
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Affiliation(s)
- Shenglin Xian
- Department of Cardiology, The First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi 530021, P.R. China.,Guangxi Key Laboratory of Precision Medicine in Cardio-cerebrovascular Disease Control and Prevention and Guangxi Clinical Research Center for Cardio-cerebrovascular Diseases, Guangxi Medical University, Nanning, Guangxi 530021, P.R. China
| | - Zhiyu Zeng
- Department of Cardiology, The First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi 530021, P.R. China.,Guangxi Key Laboratory of Precision Medicine in Cardio-cerebrovascular Disease Control and Prevention and Guangxi Clinical Research Center for Cardio-cerebrovascular Diseases, Guangxi Medical University, Nanning, Guangxi 530021, P.R. China
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Kim SG, Sung JY, Kim JR, Choi HC. Nifedipine-induced AMPK activation alleviates senescence by increasing autophagy and suppressing of Ca2+ levels in vascular smooth muscle cells. Mech Ageing Dev 2020; 190:111314. [DOI: 10.1016/j.mad.2020.111314] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Revised: 06/29/2020] [Accepted: 07/10/2020] [Indexed: 12/25/2022]
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Li W, Zhao J, Yao Q, Li W, Zhi W, Zang L, Liu F, Niu X. Polysaccharides from Poria cocos (PCP) inhibits ox-LDL-induced vascular smooth muscle cells proliferation and migration by suppressing TLR4/NF-κB p65 signaling pathway. J Funct Foods 2019. [DOI: 10.1016/j.jff.2019.05.047] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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Nifedipine Modulates Renal Lipogenesis via the AMPK-SREBP Transcriptional Pathway. Int J Mol Sci 2019; 20:ijms20071570. [PMID: 30934807 PMCID: PMC6480582 DOI: 10.3390/ijms20071570] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2019] [Revised: 03/16/2019] [Accepted: 03/27/2019] [Indexed: 12/13/2022] Open
Abstract
Lipid accumulation in renal cells has been implicated in the pathogenesis of obesity-related kidney disease, and lipotoxicity in the kidney can be a surrogate marker for renal failure or renal fibrosis. Fatty acid oxidation provides energy to renal tubular cells. Ca2+ is required for mitochondrial ATP production and to decrease reactive oxygen species (ROS). However, how nifedipine (a calcium channel blocker) affects lipogenesis is unknown. We utilized rat NRK52E cells pre-treated with varying concentrations of nifedipine to examine the activity of lipogenesis enzymes and lipotoxicity. A positive control exposed to oleic acid was used for comparison. Nifedipine was found to activate acetyl Coenzyme A (CoA) synthetase, acetyl CoA carboxylase, long chain fatty acyl CoA elongase, ATP-citrate lyase, and 3-hydroxy-3-methyl-glutaryl-coenzyme A (HMG CoA) reductase, suggesting elevated production of cholesterol and phospholipids. Nifedipine exposure induced a vast accumulation of cytosolic free fatty acids (FFA) and stimulated the production of reactive oxygen species, upregulated CD36 and KIM-1 (kidney injury molecule-1) expression, inhibited p-AMPK activity, and triggered the expression of SREBP-1/2 and lipin-1, underscoring the potential of nifedipine to induce lipotoxicity with renal damage. To our knowledge, this is the first report demonstrating nifedipine-induced lipid accumulation in the kidney.
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Osman I, Fairaq A, Segar L. Pioglitazone Attenuates Injury-Induced Neointima Formation in Mouse Femoral Artery Partially through the Activation of AMP-Activated Protein Kinase. Pharmacology 2017; 100:64-73. [PMID: 28482342 DOI: 10.1159/000471769] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2016] [Accepted: 03/16/2017] [Indexed: 12/15/2022]
Abstract
BACKGROUND/AIMS Pioglitazone (PIO), an antidiabetic drug, has been shown to attenuate vascular smooth muscle cell (VSMC) proliferation, which is a major event in atherosclerosis and restenosis after angioplasty. Till date, the likely contributory role of AMP-activated protein kinase (AMPK) toward PIO inhibition of VSMC proliferation has not been examined in vivo. This study is aimed at determining whether pharmacological inhibition of AMPK would prevent the inhibitory effect of PIO on neointima formation in a mouse model of arterial injury. METHODS Male CJ57BL/6J mice were subjected to femoral artery injury using guidewire. PIO (20 mg/kg/day) was administered orally 1 day before surgery and for 3 weeks until sacrifice in the absence or presence of compound C (an AMPK inhibitor). Injured femoral arteries were used for morphometric analysis of neointima formation. Aortic tissue lysates were used for immunoblot analysis of phosphorylated AMPK. RESULTS PIO treatment resulted in a significant decrease in intima-to-media ratio by ∼50.3% (p < 0.05, compared with vehicle control; n = 6), which was accompanied by enhanced phosphorylation of AMPK by ∼85% in the vessel wall. Compound C treatment led to a marked reduction in PIO-mediated inhibition of neointima formation. CONCLUSION PIO attenuates injury-induced neointima formation, in part, through the activation of AMPK.
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Affiliation(s)
- Islam Osman
- Center for Pharmacy and Experimental Therapeutics, University of Georgia College of Pharmacy, Augusta University, Augusta, GA, USA
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Lee KY, Lee DH, Choi HC. Mesoglycan attenuates VSMC proliferation through activation of AMP-activated protein kinase and mTOR. Clin Hypertens 2016; 22:2. [PMID: 26893937 PMCID: PMC4750809 DOI: 10.1186/s40885-016-0037-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2015] [Accepted: 01/08/2016] [Indexed: 01/03/2023] Open
Abstract
BACKGROUND Vascular smooth muscle cells (VSMC) proliferation contributes significantly to intimal thickening in atherosclerosis and restenosis diseases. Platelet derived growth factor (PDGF) has been implicated in VSMC proliferation though the activation of multiple growth-promoting signals. Mesoglycan, a natural glycosaminoglycans preparation, is reported to show vascular protective effect. However, the mechanisms by which mesoglycan inhibits proliferation of VSMC are not fully understood. Here, we investigated whether mesoglycan exert therapeutic effect via AMP-activated protein kinase (AMPK) and its underlying mechanism. METHODS We cultured VSMC with increasing doses of mesoglycan. AMPK activation was measured by western blot analysis and cell proliferation was measured by flow cytometry. RESULTS Mesoglycan dose- and time- dependently increased the phosphorylation of AMPK (Thr(172)) and its upstream target, LKB1 (Ser(428)) and its downstream, ACC (Ser(79)) in VSMCs. Mesoglycan also blocked the PDGF-stimulated cell cycle progression through the G0/G1 arrest. AMPK DNα1, AMPK DNα2 or AMPK siRNA reduced the mesoglycan-mediated inhibition of VSMC proliferation. AMPK signaling activated by mesoglycan regulates mTOR phosphorylation which closely related to cell proliferation. CONCLUSION These data suggest that mesoglycan-induced AMPK activation suppress the VSMC proliferation via mTOR-dependent mechanism and mesoglycan may have beneficial effects on vascular proliferative disorders such as atherosclerosis.
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Affiliation(s)
- Kyung Young Lee
- Department of Pharmacology, College of Medicine, Yeungnam University, 170 Hyunchung-Ro, Nam-Gu, Daegu, 42415 Republic of Korea ; Smart-aging Convergence Research Center, College of Medicine, Yeungnam University, 170 Hyunchung-Ro, Daegu, 42125 Republic of Korea
| | - Dong Hyup Lee
- Department of Thoracic and Cardiovascular Surgery, College of Medicine, Yeungnam University, 170 Hyunchung-Ro, Nam-Gu, Daegu, 42415 Republic of Korea
| | - Hyoung Chul Choi
- Department of Pharmacology, College of Medicine, Yeungnam University, 170 Hyunchung-Ro, Nam-Gu, Daegu, 42415 Republic of Korea ; Smart-aging Convergence Research Center, College of Medicine, Yeungnam University, 170 Hyunchung-Ro, Daegu, 42125 Republic of Korea
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Choi SH, Park S, Oh CJ, Leem J, Park KG, Lee IK. Dipeptidyl peptidase-4 inhibition by gemigliptin prevents abnormal vascular remodeling via NF-E2-related factor 2 activation. Vascul Pharmacol 2015; 73:11-9. [PMID: 26187356 DOI: 10.1016/j.vph.2015.07.005] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2015] [Revised: 06/10/2015] [Accepted: 07/11/2015] [Indexed: 12/25/2022]
Abstract
Dipeptidyl peptidase-4 (DPP-4) inhibitors exert a potent anti-hyperglycemic effect and reduce cardiovascular risk in type 2 diabetic patients. Several studies have shown that DPP-4 inhibitors including sitagliptin have beneficial effects in atherosclerosis and cardiac infarction involving reactive oxygen species. Here, we show that gemigliptin can directly attenuate the abnormal proliferation and migration of vascular smooth muscle cells (VSMCs) via enhanced NF-E2-related factor 2 (Nrf2) activity. Gemigliptin dramatically prevented ligation injury-induced neointimal hyperplasia in mouse carotid arteries. Likewise, the proliferation of primary VSMCs was significantly attenuated by gemigliptin in a dose-dependent manner consistent with a decrease in phospho-Rb, resulting in G1 cell cycle arrest. We found that gemigliptin enhanced Nrf2 activity not only by mRNA expression, but also by increasing Keap1 proteosomal degradation by p62, leading to the induction of Nrf2 target genes such as HO-1 and NQO1. The anti-proliferative role of gemigliptin disappeared with DPP-4 siRNA knockdown, indicating that the endogenous DPP-4 in VSMCs contributed to the effect of gemigliptin. In addition, gemigliptin diminished TNF-α-mediated cell adhesion molecules such as MCP-1 and VCAM-1 and reduced MMP2 activity in VSMCs. Taken together, our data indicate that gemigliptin exerts a preventative effect on the proliferation and migration of VSMCs via Nrf2.
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Affiliation(s)
- Seung Hee Choi
- Department of Biomedical Science, Graduate School, Kyungpook National University, Daegu, Republic of Korea
| | - Sungmi Park
- Leading-Edge Research Center for Drug Discovery and Development for Diabetes and Metabolic Disease, Kyungpook National University, Daegu, Republic of Korea
| | - Chang Joo Oh
- Research Institutes of Aging and Metabolism, Kyungpook National University, Daegu, Republic of Korea
| | - Jaechan Leem
- Leading-Edge Research Center for Drug Discovery and Development for Diabetes and Metabolic Disease, Kyungpook National University, Daegu, Republic of Korea
| | - Keun-Gyu Park
- Leading-Edge Research Center for Drug Discovery and Development for Diabetes and Metabolic Disease, Kyungpook National University, Daegu, Republic of Korea; Department of Internal Medicine, School of Medicine, Kyungpook National University, Daegu, Republic of Korea
| | - In-Kyu Lee
- Leading-Edge Research Center for Drug Discovery and Development for Diabetes and Metabolic Disease, Kyungpook National University, Daegu, Republic of Korea; Research Institutes of Aging and Metabolism, Kyungpook National University, Daegu, Republic of Korea; Department of Internal Medicine, School of Medicine, Kyungpook National University, Daegu, Republic of Korea; BK21 Plus KNU Biomedical Convergence Program, Kyungpook National University, Daegu, Republic of Korea.
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Fang L, Turtschi S, Mozaffarieh M. The effect of nifedipine on retinal venous pressure of glaucoma patients with the Flammer-Syndrome. Graefes Arch Clin Exp Ophthalmol 2015; 253:935-9. [PMID: 25863672 DOI: 10.1007/s00417-015-3001-7] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2014] [Revised: 03/17/2015] [Accepted: 03/25/2015] [Indexed: 01/04/2023] Open
Abstract
PURPOSE The purpose was to measure the retinal venous pressure (RVP) in both eyes of primary open-angle glaucoma (POAG) patients before and 3 weeks after treatment with low-dosed Nifedipine. METHODS This retrospective study included 20 POAG patients who were treated with Nifedipine (5 mg daily) and 20 untreated control POAG patients. In both the treated and untreated control group, a distinction was made between those patients who had the Flammer-Syndrome (FS) and those who did not. The RVP was measured in all patients bilaterally at baseline and 3 weeks later by means of contact lens ophthalmodynamometry and the RVP measurements of the treated POAG patients were compared to the RVPs of the untreated POAG controls. Ophthalmodynamometry is done by applying an increasing force on the eye via a contact lens. The minimum force required to induce a venous pulsation is called the ophthalmodynamometric force (ODF). The RVP is defined and calculated as the sum of ODF and intraocular pressure (IOP) [RVP = ODF + IOP]. RESULTS The RVP decreased significantly after 3 weeks in both eyes of patients treated with low-dosed Nifedipine compared to the untreated group (mean decrease of 12.5 mmHg (SD 12.5), P < 0.001). A larger response to therapy was found in patients with the FS compared to patients lacking the FS (mean decrease of 16.07 vs. 7.28 mmHg, confidence Interval (CI): 5.2 to 9.3 vs. 12.3 to 19.7; P < 0.001). No significant differences were accounted for in the IOP's of the patients after treatment. In the untreated control group, no significant differences were accounted for either in the RVP or the IOP after 3 weeks. CONCLUSIONS Treatment with low-dosed Nifedipine decreases RVP in both eyes of glaucoma patients, particularly in those with the Flammer-Syndrome. This effect may be due to the partial inhibition of Endothelin-1 (ET-1) by Nifedipine.
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Affiliation(s)
- L Fang
- Department of Ophthalmology, University of Basel, Mittlere Strasse 91, 4031, Basel, Switzerland
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Improving arteriovenous fistula patency: Transdermal delivery of diclofenac reduces cannulation-dependent neointimal hyperplasia via AMPK activation. Vascul Pharmacol 2015; 71:108-15. [PMID: 25866325 PMCID: PMC4534710 DOI: 10.1016/j.vph.2015.02.012] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2014] [Revised: 02/02/2015] [Accepted: 02/18/2015] [Indexed: 11/24/2022]
Abstract
Creation of an autologous arteriovenous fistula (AVF) for vascular access in haemodialysis is the modality of choice. However neointimal hyperplasia and loss of the luminal compartment result in AVF patency rates of ~ 60% at 12 months. The exact cause of neointimal hyperplasia in the AVF is poorly understood. Vascular trauma has long been associated with hyperplasia. With this in mind in our rabbit model of AVF we simulated cannulation autologous to that undertaken in vascular access procedures and observed significant neointimal hyperplasia as a direct consequence of cannulation. The neointimal hyperplasia was completely inhibited by topical transdermal delivery of the non-steroidal anti-inflammatory (NSAID) diclofenac. In addition to the well documented anti-inflammatory properties we have identified novel anti-proliferative mechanisms demonstrating diclofenac increases AMPK-dependent signalling and reduced expression of the cell cycle protein cyclin D1. In summary prophylactic transdermal delivery of diclofenac to the sight of AVF cannulation prevents adverse neointimal hyperplasic remodelling and potentially offers a novel treatment option that may help prolong AVF patency and flow rates.
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Nifedipine inhibits ox-LDL-induced lipid accumulation in human blood-derived macrophages. Biochem Biophys Res Commun 2015; 457:440-4. [DOI: 10.1016/j.bbrc.2015.01.010] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2014] [Accepted: 01/05/2015] [Indexed: 11/20/2022]
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15
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Soga M, Ohashi A, Taniguchi M, Matsui T, Tsuda T. The di-peptide Trp-His activates AMP-activated protein kinase and enhances glucose uptake independently of insulin in L6 myotubes. FEBS Open Bio 2014; 4:898-904. [PMID: 25383313 PMCID: PMC4223153 DOI: 10.1016/j.fob.2014.10.008] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2014] [Revised: 10/16/2014] [Accepted: 10/16/2014] [Indexed: 11/30/2022] Open
Abstract
WH activates AMPK, and enhances glucose uptake in L6 myotubes independently of insulin. WH induces ATP depletion and LKB1 phosphorylates AMPK. Activation of AMPK by WH is not due to Ca2+ dependent pathway. L6 myotubes have only one type of peptide transporter (PHT1; SLC15a4). WH activates AMPK via incorporation into cells from PHT1.
The di-peptide Trp-His (WH) has vasorelaxant and anti-atherosclerotic functions. We hypothesized that WH has multiple biological functions and may aid AMP-activated protein kinase (AMPK) activation and affect the glucose transport system in skeletal muscle. First, we examined whether WH or His-Trp (HW) can activate AMPKα. Treatment of L6 myotubes with WH or HW significantly increased phosphorylation of AMPKα. WH activated AMPK independently of insulin and significantly increased glucose uptake into L6 myotubes following translocation of glucose transporter 4 (Glut4) to the plasma membrane. This activation was induced by the LKB1 pathway but was independent of changes in intracellular Ca2+ levels and the Ca2+/calmodulin-dependent kinase pathway. L6 myotubes express only one type of oligopeptide transporter, peptide/histidine transporter 1 (PHT1, also known as SLC15a4), and WH is incorporated into cells and activates AMPKα following PHT1-mediated cell uptake. These findings indicate that (1) WH activates AMPK and insulin independently enhances glucose uptake following translocation of Glut4 to the plasma membrane, (2) activation of AMPKα by WH is mediated by the LKB1 pathway, without altering the Ca2+-dependent pathway, and (3) L6 myotubes express only one type of peptide transporter (PHT1; SLC15a4), which incorporates WH into cells to activate AMPKα.
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Key Words
- 2DG, 2-deoxy-d-glucose
- AICAR, 5-aminoimidazole-4-carboxamide ribonucleoside
- AMP-activated protein kinase
- AMPK, AMP-activated protein kinase
- CaMK, Ca2+/calmodulin-dependent kinase
- DMEM, Dulbecco’s modified Eagle’s medium
- Glucose transporter 4
- Glut, glucose transporter
- IRS-1, insulin receptor substrate-1
- KRH, Krebs–Ringer–HEPES buffer
- LKB1
- PHT1, peptide/histidine transporter 1
- PM, plasma membrene
- Peptide transporter
- TEA, triethanolamine
- Trp-His
- VDCC, voltage-dependent calcium channel
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Affiliation(s)
- Minoru Soga
- College of Bioscience and Biotechnology, Chubu University, Kasugai, Aichi 487-8501, Japan
| | - Ayaka Ohashi
- College of Bioscience and Biotechnology, Chubu University, Kasugai, Aichi 487-8501, Japan
| | - Megumi Taniguchi
- College of Bioscience and Biotechnology, Chubu University, Kasugai, Aichi 487-8501, Japan
| | - Toshiro Matsui
- Faculty of Agriculture, Graduate School of Kyushu University, Fukuoka 812-8581, Japan
| | - Takanori Tsuda
- College of Bioscience and Biotechnology, Chubu University, Kasugai, Aichi 487-8501, Japan
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Zhang Q, Ma AZS, Song ZY, Wang C, Fu XD. Nifedipine enhances cholesterol efflux in RAW264.7 macrophages. Cardiovasc Drugs Ther 2014; 27:425-31. [PMID: 23812592 DOI: 10.1007/s10557-013-6472-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
PURPOSE Studies have shown that nifedipine protects against atherosclerotic progression, but its underlying mechanisms remain unclear. In this study, we examined if nifedipine increases macrophage cholesterol efflux, a pathway known to inhibit atherogenesis. METHODS We evaluated the ability of different doses of nifedipine to affect cholesterol efflux in RAW264.7 macrophages and its relationship with mRNA and protein levels of several well-characterized proteins involved in cholesterol efflux, including ABCA1, ABCG1, SR-BI and LXRα, using quantitative real-time PCR, Western blotting, and siRNA techniques. RESULTS Nifedipne at 1, 10, and 100 nmol/L increased apoA-I-mediated cholesterol efflux from 2.55 % to 5.65 %, 6.20 %, and 6.10 %, as well as HDL-mediated cholesterol efflux from 31.0 % to 42.5 %, 46.0 %, and 43.5 %, respectively, in RAW264.7 macrophages (p < 0.05), which was associated with increased mRNA expression levels of ABCA1, ABCG1, SR-BI, and LXRα (405 %, 381 %, 336 %; 890 %, 960 %, 1002 %; 285 %, 325 %, 336 %; 482 %, 445 %, 405 %, respectively, p < 0.05), and with increased protein levels of ABCA1, ABCG1, SR-BI, and LXRα (428 %, 492 %, 361 %; 288 %, 331 %, 365 %; 283 %, 320 %, 505 %; 581 %, 678 %, 608 %, respectively, p < 0.05). SiRNA-mediated silencing of LXRα revealed that LXRα was involved in these increases and the enhanced cholesterol efflux. CONCLUSION Nifedipine may protect against atherosclerosis partly by promoting macrophage cholesterol efflux through the stimulation of LXRα-dependent expression of ABCA1, ABCG1, and SR-BI.
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Affiliation(s)
- Qian Zhang
- Department of Cardiology, Southwest Hospital, The Third Military Medical University, Chongqing, China
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17
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Huang X, Fan R, Lu Y, Yu C, Xu X, Zhang X, Liu P, Yan S, Chen C, Wang L. Regulatory effect of AMP-activated protein kinase on pulmonary hypertension induced by chronic hypoxia in rats: in vivo and in vitro studies. Mol Biol Rep 2014; 41:4031-41. [PMID: 24566685 DOI: 10.1007/s11033-014-3272-9] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2013] [Accepted: 02/13/2014] [Indexed: 10/25/2022]
Abstract
Activation of AMP-activated protein kinase (AMPK) plays an important role in cardiovascular protection. It can inhibit arterial smooth muscle cell proliferation and cardiac fibroblast collagen synthesis induced by anoxia. However, the role of AMPK-dependent signalling cascades in the pulmonary vascular system is currently unknown. This study aims to determine the effects of AMPK on pulmonary hypertension and pulmonary vessel remodelling induced by hypoxia in rats using in vivo and in vitro studies. In vivo study: pulmonary hypertension, right ventricular hypertrophy and pulmonary vascular remodelling were found in hypoxic rats. Meanwhile, AMPKα1 and phosphorylated AMPKα1 were increased markedly in pulmonary arterioles and lung tissues. Mean pulmonary arterial pressure, index of right ventricular hypertrophy and parameters of pulmonary vascular remodelling, including vessel wall area/total area, density of nuclei in medial smooth muscle cells, and thickness of the medial smooth muscle cell layer were markedly suppressed by AICAR, an AMPK agonist. In vitro study: the expression of AMPKα1 and phosphorylated AMPKα1 was increased in pulmonary artery smooth muscle cells (PASMCs) under hypoxic conditions. The effects of PASMC proliferation stimulated by hypoxia were reinforced by treatment with Compound C, an AMPK inhibitor. AICAR inhibited the proliferation of PASMCs stimulated by hypoxia. These findings suggest that AMPK is involved in the formation of hypoxia-induced pulmonary hypertension and pulmonary vessel remodelling. Up-regulating AMPK can contribute to decreasing pulmonary vessel remodelling and pulmonary hypertension induced by hypoxia.
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Affiliation(s)
- Xiaoying Huang
- Division of Pulmonary Medicine, First Affiliated Hospital of Wenzhou Medical University, Wenzhou, China,
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18
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Fukuda T, Kuroda T, Kono M, Miyamoto T, Tanaka M, Matsui T. Attenuation of L-type Ca²⁺ channel expression and vasomotor response in the aorta with age in both Wistar-Kyoto and spontaneously hypertensive rats. PLoS One 2014; 9:e88975. [PMID: 24533163 PMCID: PMC3923070 DOI: 10.1371/journal.pone.0088975] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2013] [Accepted: 01/13/2014] [Indexed: 01/15/2023] Open
Abstract
Age-related vascular diseases are induced by vascular dysfunction, which involves changes in the vasomotor response. The voltage-dependent L-type calcium channel (VDCC) protein is involved in the regulation of vessel function (contraction/relaxation action). In the present study, we evaluated age-related vasomotor function and expression of the signal-related target proteins, including VDCC, using thoracic aorta from both 8- and 40-week old Wistar-Kyoto (WKY) and spontaneously hypertensive rats (SHR). In contraction experiments using aortic rings, vasomotor responses of both phenylephrine-induced contraction and acetylcholine-induced relaxation were significantly attenuated with age in SHR, whereas WKY did not lose activity with age. Contraction induced by angiotensin II was impaired only for the 40-week old SHR among all the rat groups tested, although enhanced AT1R/reduced AT2R expression with age was observed for both WKY and SHR. In contrast, a vasomotor responsiveness to Bay K 8644 (a VDCC agonist) at the initial contraction phase was significantly attenuated in both 40-week WKY and SHR with significant reduction of VDCC protein expression. The reduced VDCC expression in 40-week old rats significantly lowered the relaxation activity of VDCC blockers, such as verapamil and Trp-His, but did not affect that of nifedipine. Taken together, we provided the first evidence that aging caused a reduction of VDCC expression in rat aorta, irrespective of the rat strain, along with diminishment of the therapeutic potential of VDCC blockers.
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MESH Headings
- 3-Pyridinecarboxylic acid, 1,4-dihydro-2,6-dimethyl-5-nitro-4-(2-(trifluoromethyl)phenyl)-, Methyl ester/pharmacology
- Aging/metabolism
- Aging/physiology
- Angiotensin II/pharmacology
- Animals
- Aorta, Thoracic/drug effects
- Aorta, Thoracic/metabolism
- Aorta, Thoracic/physiology
- Calcium Channel Blockers/pharmacology
- Calcium Channels, L-Type/metabolism
- Gene Expression Regulation/drug effects
- Male
- Rats
- Rats, Inbred SHR
- Rats, Inbred WKY
- Vasoconstriction/drug effects
- Vasodilation/drug effects
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Affiliation(s)
- Toshihiko Fukuda
- The Department of Bioscience and Biotechnology, Faculty of Agriculture, Graduate School of Kyushu University, Hakozaki, Higashi-ku, Fukuoka, Japan
| | - Takahiro Kuroda
- The Department of Bioscience and Biotechnology, Faculty of Agriculture, Graduate School of Kyushu University, Hakozaki, Higashi-ku, Fukuoka, Japan
| | - Miki Kono
- The Department of Bioscience and Biotechnology, Faculty of Agriculture, Graduate School of Kyushu University, Hakozaki, Higashi-ku, Fukuoka, Japan
| | - Takahisa Miyamoto
- The Department of Bioscience and Biotechnology, Faculty of Agriculture, Graduate School of Kyushu University, Hakozaki, Higashi-ku, Fukuoka, Japan
| | - Mitsuru Tanaka
- The Department of Bioscience and Biotechnology, Faculty of Agriculture, Graduate School of Kyushu University, Hakozaki, Higashi-ku, Fukuoka, Japan
| | - Toshiro Matsui
- The Department of Bioscience and Biotechnology, Faculty of Agriculture, Graduate School of Kyushu University, Hakozaki, Higashi-ku, Fukuoka, Japan
- * E-mail:
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Jung CH, Lee MJ, Kang YM, Lee YL, Yoon HK, Kang SW, Lee WJ, Park JY. Vaspin inhibits cytokine-induced nuclear factor-kappa B activation and adhesion molecule expression via AMP-activated protein kinase activation in vascular endothelial cells. Cardiovasc Diabetol 2014; 13:41. [PMID: 24517399 PMCID: PMC3925442 DOI: 10.1186/1475-2840-13-41] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/20/2013] [Accepted: 02/11/2014] [Indexed: 12/17/2022] Open
Abstract
Background Vaspin is an adipocytokine that was recently identified in the visceral adipose tissue of diabetic rats and has anti-diabetic and anti-atherogenic effects. We hypothesized that vaspin prevents inflammatory cytokine-induced nuclear factor-kappa B (NF-κB) activation by activating AMP-activated protein kinase (AMPK) in vascular endothelial cells. Methods We examined the effects of vaspin on NF-κB activation and the expression of the NF-κB-mediated genes intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), E-selectin, and monocyte chemoattractant protein-1 (MCP-1). Human aortic endothelial cells (HAECS) were used. Tumor necrosis factor alpha (TNFα) was used as a representative proinflammatory cytokine. Results Treatment with vaspin significantly increased the phosphorylation of AMPK and acetyl-CoA carboxylase, the down-stream target of AMPK. Furthermore, treatment with vaspin significantly decreased TNFα-induced activation of NF-κB, as well as the expression of the adhesion molecules ICAM-1, VCAM-1, E-selectin, and MCP-1. These effects were abolished following transfection of AMPKα1-specific small interfering RNA. In an adhesion assay using THP-1 cells, vaspin reduced TNFα-induced adhesion of monocytes to HAECS in an AMPK-dependent manner. Conclusions Vaspin might attenuate the cytokine-induced expression of adhesion molecule genes by inhibiting NF-κB following AMPK activation.
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Affiliation(s)
| | | | | | | | | | | | | | - Joong-Yeol Park
- Department of Internal Medicine, University of Ulsan College of Medicine, Poongnap-dong, Songpa-gu, Seoul 138-736, Korea.
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20
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Zeng Y, Li C, Guan M, Zheng Z, Li J, Xu W, Wang L, He F, Xue Y. The DPP-4 inhibitor sitagliptin attenuates the progress of atherosclerosis in apolipoprotein-E-knockout mice via AMPK- and MAPK-dependent mechanisms. Cardiovasc Diabetol 2014; 13:32. [PMID: 24490809 PMCID: PMC3916068 DOI: 10.1186/1475-2840-13-32] [Citation(s) in RCA: 88] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/29/2014] [Accepted: 01/30/2014] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND The dipeptidyl peptidase-4 inhibitor sitagliptin, a new anti-diabetic medicine, is effective in treating type 2 diabetes mellitus by increasing the activation and duration of action of glucagon-like peptide-1. Since atherosclerosis is the main pathological feature of diabetic cardiovascular complications, it is important to investigate the anti-atherosclerotic effect of sitagliptin and explore the relevant mechanisms. METHODS Male apolipoprotein-E-knockout mice were randomly divided into two groups and fed either high-fat diet (HFD) or HFD plus sitagliptin at a concentration of 0.3% for 16 weeks. Body weight, food intake, blood glucose, serum lipids and adhesion molecules were measured. The atherosclerotic plaque area and its histological composition were analyzed using Sudan staining and immunohistochemistry. The expression of inflammatory cytokines (monocyte chemoattractant protein (MCP)-1 and interleukin (IL)-6) and the activation of AMP-activated protein kinase (AMPK) and mitogen-activated protein kinase (MAPK) in the aortas were determined using quantitative polymerase chain reaction and western blot, respectively. RESULTS Mice treated with sitagliptin developed fewer atherosclerotic plaques than the control group (7.64 ± 1.98% vs 12.91 ± 1.15%, p < 0.001), particularly in the aortic arch and abdominal aorta, where plaques were decreased 1.92- and 2.74-fold, respectively (p < 0.05 and p < 0.01). Sitagliptin significantly reduced the content of collagen fiber in plaques 1.2-fold (p < 0.05). Moreover, sitagliptin significantly reduced the expression of monocyte chemoattractant protein-1 and interleukin-6 in the aorta (p < 0.01 and p < 0.05), as well as the serum levels of soluble vascular cell adhesion molecule-1 and P-selectin (both p < 0.05). In addition, Sitagliptin induced phosphorylation of AMPK and Akt (p < 0.05 and p < 0.01), while suppressed phosphorylation of p38 and extracellular signal-regulated kinase (Erk) 1/2 (p < 0.05 and p < 0.01) in aortas. CONCLUSIONS Our present study indicates that sitagliptin can reduce the area of the atherosclerotic lesion, possibly by regulating the AMPK and MAPK pathways and then reducing leukocyte -endothelial cell interaction and inflammation reactions. These actions are independent of weight loss and glucose-reducing effects.
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Affiliation(s)
| | | | | | | | | | | | | | | | - Yaoming Xue
- Department of Endocrinology and Metabolism, Nanfang Hospital, Southern Medical University, Guangzhou 510150, China.
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21
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Wan J, Yamamura A, Zimnicka AM, Voiriot G, Smith KA, Tang H, Ayon RJ, Choudhury MSR, Ko EA, Wang J, Wang C, Makino A, Yuan JXJ. Chronic hypoxia selectively enhances L- and T-type voltage-dependent Ca2+ channel activity in pulmonary artery by upregulating Cav1.2 and Cav3.2. Am J Physiol Lung Cell Mol Physiol 2013; 305:L154-64. [PMID: 23686856 DOI: 10.1152/ajplung.00313.2012] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Hypoxia-induced pulmonary hypertension (HPH) is characterized by sustained pulmonary vasoconstriction and vascular remodeling, both of which are mediated by pulmonary artery smooth muscle cell (PASMC) contraction and proliferation, respectively. An increase in cytosolic Ca²⁺ concentration ([Ca²⁺]cyt) is a major trigger for pulmonary vasoconstriction and an important stimulus for cell proliferation in PASMCs. Ca²⁺ influx through voltage-dependent Ca²⁺ channels (VDCC) is an important pathway for the regulation of [Ca²⁺]cyt. The potential role for L- and T-type VDCC in the development of HPH is still unclear. Using a hypoxic-induced pulmonary hypertension mouse model, we undertook this study to identify if VDCC in pulmonary artery (PA) are functionally upregulated and determine which type of VDCC are altered in HPH. Mice subjected to chronic hypoxia developed pulmonary hypertension within 4 wk, and high-K⁺- and U-46619-induced contraction of PA was greater in chronic hypoxic mice than that in normoxic control mice. Additionally, we demonstrate that high-K⁺- and U-46619-induced Ca²⁺ influx in PASMC is significantly increased in the hypoxic group. The VDCC activator, Bay K8864, induced greater contraction of the PA of hypoxic mice than in that of normoxic mice in isometric force measurements. L-type and T-type VDCC blockers significantly attenuated absolute contraction of the PA in hypoxic mice. Chronic hypoxia did not increase high-K⁺- and U-46619-induced contraction of mesenteric artery (MA). Compared with MA, PA displayed higher expression of calcium channel voltage-dependent L-type α1C-subunit (Cav1.2) and T-type α1H-subunit (Cav3.2) upon exposure to chronic hypoxia. In conclusion, both L-type and T-type VDCC were functionally upregulated in PA, but not MA, in HPH mice, which could result from selectively increased expression of Cav1.2 and Cav3.2.
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Affiliation(s)
- Jun Wan
- Department of Medicine, Institute for Personalized Respiratory Medicine, University of Illinois at Chicago, Chicago, IL 60612, USA
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22
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Balasubramanian R, Maruoka H, Jayasekara PS, Gao ZG, Jacobson KA. AMP-activated protein kinase as regulator of P2Y(6) receptor-induced insulin secretion in mouse pancreatic β-cells. Biochem Pharmacol 2013; 85:991-8. [PMID: 23333427 PMCID: PMC3594329 DOI: 10.1016/j.bcp.2012.11.029] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2012] [Revised: 11/23/2012] [Accepted: 11/26/2012] [Indexed: 10/27/2022]
Abstract
5'-AMP-activated protein kinase (AMPK) and its pharmacological modulators have been targeted for treating type 2 diabetes. Extracellular uridine 5'-diphosphate (UDP) activates P2Y6 receptors (P2Y6Rs) in pancreatic β-cells to release insulin and reduce apoptosis, which would benefit diabetes. Here, we studied the role of P2Y6R in activation of AMPK in MIN6 mouse pancreatic β-cells and insulin secretion. Treatment with a potent P2Y6R dinucleotide agonist MRS2957 (500nM) activated AMPK, which was blocked by P2Y6R-selective antagonist MRS2578. Also, MRS2957 induced phosphorylation of acetyl-coenzyme A carboxylase (ACC), a marker of AMPK activity. Calcium chelator BAPTA-AM, calmodulin-dependent protein kinase kinase (CaMKK) inhibitor STO-069 and IP3 receptor antagonist 2-APB attenuated P2Y6R-mediated AMPK phosphorylation revealing involvement of intracellular Ca(2+) pathways. P2Y6R agonist induced insulin secretion at high glucose, which was reduced by AMPK siRNA. Thus, P2Y6R has a crucial role in β-cell function, suggesting its potential as a therapeutic target in diabetes.
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Affiliation(s)
- Ramachandran Balasubramanian
- Molecular Recognition Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892
| | - Hiroshi Maruoka
- Molecular Recognition Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892
| | - P. Suresh Jayasekara
- Molecular Recognition Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892
| | - Zhan-Guo Gao
- Molecular Recognition Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892
| | - Kenneth A. Jacobson
- Molecular Recognition Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892
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Metformin inhibits inflammatory response via AMPK-PTEN pathway in vascular smooth muscle cells. Biochem Biophys Res Commun 2012; 425:866-72. [PMID: 22898050 DOI: 10.1016/j.bbrc.2012.07.165] [Citation(s) in RCA: 116] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2012] [Accepted: 07/31/2012] [Indexed: 12/17/2022]
Abstract
Atherosclerosis is a chronic inflammation of the coronary arteries. Vascular smooth muscle cells (VSMCs) stimulated by cytokines and chemokines accelerate the inflammatory response and migrate to the injured endothelium during the progression of atherosclerosis. Activation of AMP activated protein kinase (AMPK), a key sensor maintaining metabolic homeostasis, suppresses the inflammatory response. However, how AMPK regulates the inflammatory response is poorly understood. To identify the mechanism of this response, we focused on phosphatase and tensin homolog (PTEN), which is a negative regulator of inflammation. We investigated that activation of AMPK-induced PTEN expression and suppression of the inflammatory response through the AMPK-PTEN pathway in VSMCs. We treated with the well-known AMPK activator metformin to induce PTEN expression. PTEN was induced by metformin (2mM) and inhibited by compound C (10 μM) and AMPK siRNA. Tumor necrosis factor-alpha (TNF-α) was used to induce inflammation. The inflammatory response was confirmed by cyclooxygenase (COX)-2, inducible nitric oxide synthase (iNOS) expression, and activation of nuclear factor (NF)-κB. Metformin suppressed COX-2 and iNOS mRNA and protein expression dose dependently. Treatment with compound C and bpv (pic) in the presence of metformin, iNOS and COX-2 protein expression increased. NF-κB activation decreased in response to metformin and was restored by inhibiting AMPK and PTEN. Inhibiting AMPK and PTEN restored ROS levels stimulated with TNF-α. Taken together, PTEN could be a possible downstream regulator of AMPK, and the AMPK-PTEN pathway might be important in the regulation of the inflammatory response in VSMCs.
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Choi HC. Effects of AMP-activated Protein Kinase Activating Compounds and Its Mechanism. Yeungnam Univ J Med 2012. [DOI: 10.12701/yujm.2012.29.2.77] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Affiliation(s)
- Hyoung Chul Choi
- Department of Pharmacology, College of Medicine, Yeungnam University, Daegu, Korea
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