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Ozturk N, Uslu S, Mercan T, Erkan O, Ozdemir S. Rosuvastatin Reduces L-Type Ca 2+ Current and Alters Contractile Function in Cardiac Myocytes via Modulation of β-Adrenergic Receptor Signaling. Cardiovasc Toxicol 2021; 21:422-431. [PMID: 33565033 DOI: 10.1007/s12012-021-09642-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/06/2020] [Accepted: 01/29/2021] [Indexed: 12/17/2022]
Abstract
Rosuvastatin is one of the most used statins to lower plasma cholesterol levels. Although previous studies have reported remarkable cardiovascular effects of rosuvastatin (RSV), the mechanisms of these effects are largely unknown. In this study, we investigated the acute effects of RSV on L-type Ca2+ currents and contractile function of ventricular myocytes under basal conditions and during β-adrenergic stimulation. The effects of RSV were investigated in freshly isolated adult rat ventricular myocytes. L-type Ca+2 currents and myocyte contractility were recorded using patch-clamp amplifier and sarcomere length detection system. All experimental recordings were performed at 36 ± 1 °C. L-type Ca+2 currents were significantly reduced with the administration of 1 μM RSV (~ 24%) and this reduction in Ca2+ currents was observed at almost all potential ranges applied. Suppression of L-type Ca2+ current by RSV was prevented by adenylyl cyclase (AC) and protein kinase A (PKA) inhibitors SQ 22536 and KT5720, respectively. However, inhibition of Rho-associated kinases (ROCKs) by Y-27632 or nitric oxide synthase (NOS) by L-NAME failed to circumvent the inhibitory effect of RSV. Finally, we examined the effect of RSV during β-adrenergic receptor stimulation by isoproterenol and observed that RSV significantly suppresses the β-adrenergic responses in both L-type Ca2+ currents and contraction parameters. In conclusion, RSV modulates the β-adrenergic signaling cascade and thereby mimics the impact of β-adrenergic receptor blockers in adult ventricular myocytes through modulation of the AC-cAMP-PKA pathway.
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Affiliation(s)
- Nihal Ozturk
- Department of Biophysics, Faculty of Medicine, Akdeniz University, Antalya, Turkey
| | - Serkan Uslu
- Department of Biophysics, Faculty of Medicine, Akdeniz University, Antalya, Turkey
| | - Tanju Mercan
- Department of Biophysics, Faculty of Medicine, Akdeniz University, Antalya, Turkey
| | - Orhan Erkan
- Department of Biophysics, Faculty of Medicine, Akdeniz University, Antalya, Turkey
| | - Semir Ozdemir
- Department of Biophysics, Faculty of Medicine, Akdeniz University, Antalya, Turkey.
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2
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Simvastatin causes pulmonary artery relaxation by blocking smooth muscle ROCK and calcium channels: Evidence for an endothelium-independent mechanism. PLoS One 2019; 14:e0220473. [PMID: 31369604 PMCID: PMC6675113 DOI: 10.1371/journal.pone.0220473] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2019] [Accepted: 07/16/2019] [Indexed: 01/13/2023] Open
Abstract
Simvastatin reduces pulmonary arterial pressure and right ventricular hypertrophy in animal models of pulmonary arterial hypertension (PAH) and is thought to restore endothelial dysfunction. In vivo effects of drugs are complicated by several factors and little is known of the direct effects of statins on pulmonary arteries. This study investigated the direct effects of simvastatin on pulmonary arteries isolated from rats with or without monocrotaline-induced PAH. Simvastatin suppressed contractions evoked by the thromboxane A2 receptor agonist U46619 (30 nM), the α1–adrenergic agonist phenylephrine (5 μM) and KCl (50 mM) by ~50% in healthy and diseased arteries, but did not reduce contraction evoked by sarco/endoplasmic reticulum ATPase blockers. It relaxed hypertensive arteries in the absence of stimulation. Removing the endothelium or inhibiting eNOS did not prevent the inhibition by simvastatin. Inhibiting RhoA/rho kinase (ROCK) with Y27632 (10 μM) suppressed contractions to U46619 and phenylephrine by ~80% and prevented their inhibition by simvastatin. Y27632 reduced KCl-induced contraction by ~30%, but did not prevent simvastatin inhibition. Simvastatin suppressed Ca2+ entry into smooth muscle cells, as detected by Mn2+ quench of fura-2 fluorescence. The calcium antagonist, nifedipine (1 μM), almost abolished K+-induced contraction with less effect against U46619 and phenylephrine. We conclude that simvastatin relaxes pulmonary arteries by acting on smooth muscle to interfere with signalling through G-protein coupled receptors and voltage-dependent Ca2+ entry. Its actions likely include inhibition of ROCK-dependent Ca2+ sensitisation and voltage-gated Ca2+ channels. These are likely to contribute to the beneficial effects of simvastatin in animal models of PAH.
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Kaleli-Durman D, Alp-Yıldırım Fİ, Özdemir O, Uydeş-Doğan BS. Relaxant effect of atorvastatin on isolated rat gastric fundus strips: implications for Ca 2+-signalling mechanisms. Can J Physiol Pharmacol 2019; 97:413-421. [DOI: 10.1139/cjpp-2018-0723] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Statins are determined to have various pleiotropic effects apart from their lipid-lowering properties. Herein, we investigated the direct effects of atorvastatin on gastric smooth muscle tone. Atorvastatin effectively relaxed isolated rat gastric fundus strips precontracted with acetylcholine, potassium chloride, and serotonin. Incubation of the strips with nitric oxide synthase inhibitor, l-NOARG (10−4 M, 20 min), l-type voltage-operated Ca2+ channel (VOCC) blocker, nifedipine (10−6 M, 30 min), KATP channel blocker, glibenclamide (10−5 M, 30 min), or precursor of cholesterol, mevalonate (10−2 M, 45 min) did not change the relaxations to atorvastatin. However, pretreatment of fundus strips with atorvastatin (3×10−5–3×10−4 M, 30 min) inhibited the contractions to calcium chloride (10−4–10−1 M), acetylcholine (10–4 M), and caffeine (20 mM) in the calcium-free medium. Moreover, atorvastatin reduced the contractions induced by sarco-endoplasmic reticulum Ca2+-ATPase (SERCA) inhibitor, cyclopiazonic acid (10−7–3×10−5 M). The current study demonstrated that atorvastatin produces an acute relaxant effect on gastric fundus strips, which appears to be mediated by several Ca2+-signalling mechanisms such as the blockade of l-type VOCC-independent Ca2+ entry, decrease in smooth muscle Ca2+ sensitivity, inhibition of IP3- and ryanodine-sensitive intracellular stores to mediate Ca2+ release, as well as the activation of SERCA. This acute relaxing effect seems unlikely to be related with nitric oxide, KATP channels, and the mevalonate pathway.
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Affiliation(s)
- Deniz Kaleli-Durman
- Department of Pharmacology, Faculty of Pharmacy, Istanbul University, 34116, Beyazıt, Istanbul, Turkey
| | - F. İlkay Alp-Yıldırım
- Department of Pharmacology, Faculty of Pharmacy, Istanbul University, 34116, Beyazıt, Istanbul, Turkey
| | - Osman Özdemir
- Department of Pharmacology, Faculty of Pharmacy, Istanbul University, 34116, Beyazıt, Istanbul, Turkey
- Department of Pharmacology, Faculty of Health Sciences, Cyprus International University, Lefkoşa, North Cyprus, Cyprus
| | - B. Sönmez Uydeş-Doğan
- Department of Pharmacology, Faculty of Pharmacy, Istanbul University, 34116, Beyazıt, Istanbul, Turkey
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Koh YK, Kim KH, Choi MS, Koh YY, Lim DY. Simvastatin reduces adrenal catecholamine secretion evoked by stimulation of cholinergic nicotinic and angiotensinergic AT 1 receptors. Arch Pharm Res 2018; 41:333-346. [PMID: 29460135 DOI: 10.1007/s12272-018-1007-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2017] [Accepted: 02/04/2018] [Indexed: 11/24/2022]
Abstract
We investigated the influence of simvastatin, a statin, on the secretion of catecholamines (CA) in rat adrenal glands, and clarified its action mechanism. Simvastatin suppressed acetylcholine (ACh)-evoked CA release in a dose- and time-dependent fashion. In the presence of simvastatin, CA secretion evoked by 1.1-dimethyl-4-phenyl piperazinium iodide (DMPP), angiotensin II, high K+, veratridine, and Bay-K-8644 was time-dependently inhibited. However, in the simultaneous presence of simvastatin and Nω-nitro-L-arginine methyl ester hydrochloride, CA secretion evoked by angiotensin II and DMPP recovered to control levels. Adrenal NO release was increased by simvastatin-treatment. Simvastatin-inhibited CA secretion was not affected by treatment with mevalonate. Pravastatin did not influence ACh-evoked CA secretion, while atorvastatin reduced it. In the simultaneous presence of simvastatin and fimasartan, ACh-induced CA release was markedly reduced compared to that of fimasartan-treatment alone. We present the first evidence that simvastatin reduces adrenal CA secretion induced by stimulation of nicotinic and AT1-receptors. Simvastatin-induced inhibition seems to involve reducing the influx of both Ca2+ and Na+ into adrenochromaffin cells, partly via the elevation of NO production by NO synthase activation, without inhibition of 3-hydroxy-methylglutaryl coenzyme A reductase. Co-administration of simvastatin and fimasartan may be clinically helpful for the treatment of cardiovascular diseases.
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Affiliation(s)
- Young-Kwon Koh
- Department of Pediatrics, College of Medicine, Chosun University, Kwangju, 61453, Korea
| | - Ki-Hwan Kim
- Department of Internal Medicine, Seoul National University Boramae Medical Center, Seoul, 07061, Korea
| | - Mee-Sung Choi
- Department of Leisure & Sport, College of Public Health and Welfare, Dongshin University, Naju, Chollanam-Do Province, 58245, Korea
| | - Young-Youp Koh
- Department of Internal Medicine (Cardiology), College of Medicine, Chosun University, Gwangju, 501-759, Korea
| | - Dong-Yoon Lim
- Department of Pharmacology, College of Medicine, Chosun University, 309 Pilmoondae-Ro, Dong-Gu, Gwangju, 61452, Korea.
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Lovastatin suppresses hyperexcitability and seizure in Angelman syndrome model. Neurobiol Dis 2017; 110:12-19. [PMID: 29097328 DOI: 10.1016/j.nbd.2017.10.016] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2017] [Revised: 10/11/2017] [Accepted: 10/27/2017] [Indexed: 11/22/2022] Open
Abstract
Epilepsy is prevalent and often medically intractable in Angelman syndrome (AS). AS mouse model (Ube3am-/p+) shows reduced excitatory neurotransmission but lower seizure threshold. The neural mechanism linking the synaptic dysfunction to the seizure remains elusive. We show that the local circuits of Ube3am-/p+in vitro are hyperexcitable and display a unique epileptiform activity, a phenomenon that is reminiscent of the finding in fragile X syndrome (FXS) mouse model. Similar to the FXS model, lovastatin suppressed the epileptiform activity and audiogenic seizures in Ube3am-/p+. The in vitro model of Ube3am-/p+ is valuable for dissection of neural mechanism and epilepsy drug screening in vivo.
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Huang Y, Smith CA, Chen G, Sharma B, Miner AS, Barbee RW, Ratz PH. The AMP-Dependent Protein Kinase (AMPK) Activator A-769662 Causes Arterial Relaxation by Reducing Cytosolic Free Calcium Independently of an Increase in AMPK Phosphorylation. Front Pharmacol 2017; 8:756. [PMID: 29093683 PMCID: PMC5651270 DOI: 10.3389/fphar.2017.00756] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2017] [Accepted: 10/05/2017] [Indexed: 12/15/2022] Open
Abstract
Although recent studies reveal that activation of the metabolic and Ca2+ sensor AMPK strongly inhibits smooth muscle contraction, there is a paucity of information about the potential linkage between pharmacological AMPK activation and vascular smooth muscle (VSM) contraction regulation. Our aim was to test the general hypothesis that the allosteric AMPK activator A-769662 causes VSM relaxation via inhibition of contractile protein activation, and to specifically determine which activation mechanism(s) is(are) affected. The ability of A-769662 to cause endothelium-independent relaxation of contractions induced by several contractile stimuli was examined in large and small musculocutaneous and visceral rabbit arteries. For comparison, the structurally dissimilar AMPK activators MET, SIM, and BBR were assessed. A-769662 displayed artery- and agonist-dependent differential inhibitory activities that depended on artery size and location. A-769662 did not increase AMPK-pT172 levels, but did increase phosphorylation of the downstream AMPK substrate, acetyl-CoA carboxylase (ACC). A-769662 did not inhibit basal phosphorylation levels of several contractile protein regulatory proteins, and did not alter the activation state of rhoA. A-769662 did not inhibit Ca2+- and GTPγS-induced contractions in β-escin-permeabilized muscle, suggesting that A-769662 must act by inhibiting Ca2+ signaling. In intact artery, A-769662 immediately reduced basal intracellular free calcium ([Ca2+]i), inhibited a stimulus-induced increase in [Ca2+]i, and inhibited a cyclopiazonic acid (CPA)-induced contraction. MET increased AMPK-pT172, and caused neither inhibition of contraction nor inhibition of [Ca2+]i. Together, these data support the hypothesis that the differential inhibition of stimulus-induced arterial contractions by A-769662 was due to selective inhibition of a Ca2+ mobilization pathway, possibly involving CPA-dependent Ca2+ entry via an AMPK-independent pathway. That MET activated AMPK without causing arterial relaxation suggests that AMPK activation does not necessarily cause VSM relaxation.
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Affiliation(s)
- Yi Huang
- Department of Emergency Medicine and Physiology, Virginia Commonwealth University, Richmond, VA, United States
| | - Corey A Smith
- Department of Biochemistry and Molecular Biology, School of Medicine, Virginia Commonwealth University, Richmond, VA, United States
| | - Grace Chen
- Department of Biochemistry and Molecular Biology, School of Medicine, Virginia Commonwealth University, Richmond, VA, United States
| | - Bharti Sharma
- Department of Biochemistry and Molecular Biology, School of Medicine, Virginia Commonwealth University, Richmond, VA, United States
| | - Amy S Miner
- Department of Biochemistry and Molecular Biology, School of Medicine, Virginia Commonwealth University, Richmond, VA, United States
| | - Robert W Barbee
- Department of Emergency Medicine and Physiology, Virginia Commonwealth University, Richmond, VA, United States
| | - Paul H Ratz
- Department of Biochemistry and Molecular Biology, School of Medicine, Virginia Commonwealth University, Richmond, VA, United States
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Fu ZJ, Zhong XZ, Ma WH, Zhang WD, Shi CY. Lipophilic but not hydrophilic statin functionally inhibit volume-activated chloride channels by inhibiting NADPH oxidase in monocytes. Biochem Biophys Res Commun 2016; 481:117-124. [PMID: 27818195 DOI: 10.1016/j.bbrc.2016.11.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2016] [Accepted: 11/02/2016] [Indexed: 11/27/2022]
Abstract
Volume-activated Cl- channels (VACCs) can be activated by hypotonic solutions and have been identified in many cell types. Here, we investigated the effects of different statins on VACCs in monocytes. Whole-cell patch clamp recordings demonstrated that a hypotonic solution induced 5-nitro-2- (3-phenylpropylamino) benzoic acid (NPPB)- and 4,4'-diisothiocyanatostilbene-2, 2'-disulfonic acid (DIDS)-sensitive VACC currents in human peripheral monocytes and RAW 264.7 cells. The VACC currents were inhibited by the lipophilic statin (simvastatin) but not by the hydrophilic simvastatin acid and pravastatin. A low-molecular-weight superoxide anion scavenger (tiron, 1 mM) and inhibitor of NADPH oxidase (DPI 10 μM) was able to abolish the VACC currents. A hypotonic solution increased the reactive oxygen species (ROS) detected by the fluorescence of dichlorodihydrofluorescein (DCF), which was abolished by tiron and DPI. NPPB, DIDS, and simvastatin but not pravastatin decreased the fluorescence of DCF. Simvastatin could not further decrease VACC currents when pretreated with tiron or DPI, whereas exogenous H2O2 (100 μM), increased the VACC currents and overcame the blockade of VACC currents by simvastatin. Functionally, hypotonic solution increased the TNF-α mRNA expression, which could be decreased by tiron, DPI, NPPB, DIDS and simvastatin but not pravastatin. However, simvastatin could not decrease the TNF-α expression further when pretreatment with tiron, DPI, NPPB or DIDS. We conclude that lipophilic (simvastatin) rather than hydrophilic statin inhibit VACCs and decrease hyposmolality induced inflammation in monocytes by inhibiting NADPH oxidase.
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Affiliation(s)
- Zhi-Jie Fu
- Department of Otorhinolaryngology, Shandong Provincial Qianfoshan Hospital, Shandong University, Jinan 250014, China
| | - Xue-Zhen Zhong
- Department of Cardiovascular Disease, Jinan Central Hospital Affiliated to Shandong University, Shandong, Jinan 250013, China
| | - Wei-Hong Ma
- Department of Cardiology, The Second Hospital of Shandong University, Jinan 250033, China
| | - Wen-Dong Zhang
- Department of Pharmacy, QiLu Hospital, Shandong University, Jinan 250012, China.
| | - Cheng-Yao Shi
- Department of Pharmacy, QiLu Hospital, Shandong University, Jinan 250012, China
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8
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Almukhtar H, Garle M, Smith P, Roberts R. Effect of simvastatin on vascular tone in porcine coronary artery: Potential role of the mitochondria. Toxicol Appl Pharmacol 2016; 305:176-185. [DOI: 10.1016/j.taap.2016.06.024] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2016] [Revised: 06/08/2016] [Accepted: 06/21/2016] [Indexed: 12/17/2022]
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9
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Ma Y, Kong L, Qi S, Wang D. Atorvastatin blocks increased l-type Ca2+ current and cell injury elicited by angiotensin II via inhibiting oxide stress. Acta Biochim Biophys Sin (Shanghai) 2016; 48:378-84. [PMID: 26940997 DOI: 10.1093/abbs/gmw009] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2015] [Accepted: 12/12/2015] [Indexed: 12/13/2022] Open
Abstract
Thel-type Ca(2+)current (ICa,l) plays a crucial role in shaping action potential and is involved in cardiac arrhythmia. Statins have been demonstrated to contribute to anti-apoptotic and anti-arrhythmic effects in the heart. Here, we examined whether atorvastatin regulates theICa,land cell injury induced by angiotensin II (AngII) as well as the putative intracellular cascade responsible for the effects. Cultured neonatal rat ventricular myocytes were incubated with AngII for 24 h, and then cell injury and expression levels of Nox2/gp91(phox), p47(phox) ,and Cav1.2 were analyzed. In addition,ICa,lwas recorded using the whole-cell patch-clamp technique, and mechanisms of atorvastatin actions were also investigated. It was found that the number of apoptotic cardiomyocytes was increased and cell viability was significantly decreased after AngII administration. AngII also augmented the expressions of Nox2/gp91(phox)and p47(phox)compared with control cardiomyocytes. Exposure to AngII evokedICa,lin a voltage-dependent manner without affecting theI-Vrelationship. In addition, AngII enhanced membrane Cav1.2 expression. These effects were abolished in the presence of the reactive oxygen species (ROS) scavenger, manganese (III)-tetrakis 4-benzoic acid porphyrin [Mn(III)TBAP], or the 3-hydroxy-3-methylglutaryl-CoA reductase inhibitor, atorvastatin. These results suggested that atorvastatin mediates cardioprotection against arrhythmias and cell injury by controlling the AngII-ROS cascade.
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Affiliation(s)
- Yanzhuo Ma
- Department of Cardiology, Bethune International Peace Hospital, Shijiazhuang 050000, China
| | - Lingfeng Kong
- Department of Cardiology, Bethune International Peace Hospital, Shijiazhuang 050000, China Hebei Medical University, Shijiazhuang 050011, China
| | - Shuying Qi
- Department of Cardiology, Bethune International Peace Hospital, Shijiazhuang 050000, China
| | - Dongmei Wang
- Department of Cardiology, Bethune International Peace Hospital, Shijiazhuang 050000, China
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Alp Yildirim Fİ, Kaleli Durman D, Aypar E, Ark M, Özdemir O, Uydeş Doğan BS. Atorvastatin acutely reduces the reactivity to spasmogens in rat aorta: implication of the inhibition of geranylgeranylation and MYPT-1 phosphorylation. Fundam Clin Pharmacol 2016; 30:96-106. [DOI: 10.1111/fcp.12173] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2015] [Revised: 11/03/2015] [Accepted: 11/20/2015] [Indexed: 12/17/2022]
Affiliation(s)
- Fatoş İlkay Alp Yildirim
- Department of Pharmacology; Faculty of Pharmacy; Istanbul University; 34116, Beyazit, Istanbul Turkey
| | - Deniz Kaleli Durman
- Department of Pharmacology; Faculty of Pharmacy; Istanbul University; 34116, Beyazit, Istanbul Turkey
| | - Eda Aypar
- Department of Pharmacology; Faculty of Pharmacy; Gazi University; 06330, Etiler, Ankara Turkey
| | - Mustafa Ark
- Department of Pharmacology; Faculty of Pharmacy; Gazi University; 06330, Etiler, Ankara Turkey
| | - Osman Özdemir
- Department of Pharmacology; Faculty of Pharmacy; Istanbul University; 34116, Beyazit, Istanbul Turkey
- Department of Pharmacology; Faculty of Health Sciences; Cyprus International University; Lefkoşa North Cyprus Cyprus
| | - Birsel Sönmez Uydeş Doğan
- Department of Pharmacology; Faculty of Pharmacy; Istanbul University; 34116, Beyazit, Istanbul Turkey
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Attenuation of acetylcholine activated potassium current (I KACh) by simvastatin, not pravastatin in mouse atrial cardiomyocyte: possible atrial fibrillation preventing effects of statin. PLoS One 2014; 9:e106570. [PMID: 25329899 PMCID: PMC4199526 DOI: 10.1371/journal.pone.0106570] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2014] [Accepted: 07/30/2014] [Indexed: 01/20/2023] Open
Abstract
Statins, 3-hydroxy-3-methyl-glutaryl-CoA reductase inhibitors, are associated with the prevention of atrial fibrillation (AF) by pleiotropic effects. Recent clinical trial studies have demonstrated conflicting results on anti-arrhythmia between lipophilic and hydrophilic statins. However, the underlying mechanisms responsible for anti-arrhythmogenic effects of statins are largely unexplored. In this study, we evaluated the different roles of lipophilic and hydrophilic statins (simvastatin and pravastatin, respectively) in acetylcholine (100 µM)-activated K+ current (IKACh, recorded by nystatin-perforated whole cell patch clamp technique) which are important for AF initiation and maintenance in mouse atrial cardiomyocytes. Our results showed that simvastatin (1–10 µM) inhibited both peak and quasi-steady-state IKACh in a dose-dependent manner. In contrast, pravastatin (10 µM) had no effect on IKACh. Supplementation of substrates for the synthesis of cholesterol (mevalonate, geranylgeranyl pyrophosphate or farnesyl pyrophosphate) did not reverse the effect of simvastatin on IKACh, suggesting a cholesterol-independent effect on IKACh. Furthermore, supplementation of phosphatidylinositol 4,5-bisphosphate, extracellular perfusion of phospholipase C inhibitor or a protein kinase C (PKC) inhibitor had no effect on the inhibitory activity of simvastatin on IKACh. Simvastatin also inhibits adenosine activated IKACh, however, simvastatin does not inhibit IKACh after activated by intracellular loading of GTP gamma S. Importantly, shortening of the action potential duration by acetylcholine was restored by simvastatin but not by pravastatin. Together, these findings demonstrate that lipophilic statins but not hydrophilic statins attenuate IKACh in atrial cardiomyocytes via a mechanism that is independent of cholesterol synthesis or PKC pathway, but may be via the blockade of acetylcholine binding site. Our results may provide important background information for the use of statins in patients with AF.
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12
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Brault M, Ray J, Gomez YH, Mantzoros CS, Daskalopoulou SS. Statin treatment and new-onset diabetes: a review of proposed mechanisms. Metabolism 2014; 63:735-45. [PMID: 24641882 DOI: 10.1016/j.metabol.2014.02.014] [Citation(s) in RCA: 158] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/20/2013] [Revised: 02/09/2014] [Accepted: 02/18/2014] [Indexed: 12/13/2022]
Abstract
New-onset diabetes has been observed in clinical trials and meta-analyses involving statin therapy. To explain this association, three major mechanisms have been proposed and discussed in the literature. First, certain statins affect insulin secretion through direct, indirect or combined effects on calcium channels in pancreatic β-cells. Second, reduced translocation of glucose transporter 4 in response to treatment results in hyperglycemia and hyperinsulinemia. Third, statin therapy decreases other important downstream products, such as coenzyme Q10, farnesyl pyrophosphate, geranylgeranyl pyrophosphate, and dolichol; their depletion leads to reduced intracellular signaling. Other possible mechanisms implicated in the effect of statins on new-onset diabetes are: statin interference with intracellular insulin signal transduction pathways via inhibition of necessary phosphorylation events and reduction of small GTPase action; inhibition of adipocyte differentiation leading to decreased peroxisome proliferator activated receptor gamma and CCAAT/enhancer-binding protein which are important pathways for glucose homeostasis; decreased leptin causing inhibition of β-cells proliferation and insulin secretion; and diminished adiponectin levels. Given that the magnitude of the risk of new-onset diabetes following statin use remains to be fully clarified and the well-established beneficial effect of statins in reducing cardiovascular risk, statins remain the first-choice treatment for prevention of CVD. Elucidation of the mechanisms underlying the development of diabetes in association with statin use may help identify novel preventative or therapeutic approaches to this problem and/or help design a new generation statin without such side-effects.
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Affiliation(s)
- Marilyne Brault
- Department of Medicine, Faculty of Medicine, McGill University, Montreal, Quebec, Canada
| | - Jessica Ray
- Department of Anatomy and Cell Biology, McGill University, Montreal, Quebec, Canada
| | - Yessica-Haydee Gomez
- Division of Internal Medicine, Department of Medicine, Faculty of Medicine, McGill University, Montreal, Quebec, Canada
| | - Christos S Mantzoros
- Endocrinology Section, VA Boston Healthcare System and Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - Stella S Daskalopoulou
- Division of Internal Medicine, Department of Medicine, Faculty of Medicine, McGill University, Montreal, Quebec, Canada; Division of Experimental Medicine, Department of Medicine, Faculty of Medicine, McGill University, Montreal, Quebec, Canada.
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Kazama I, Baba A, Maruyama Y. HMG-CoA reductase inhibitors pravastatin, lovastatin and simvastatin suppress delayed rectifier K(+)-channel currents in murine thymocytes. Pharmacol Rep 2014; 66:712-7. [PMID: 24948077 DOI: 10.1016/j.pharep.2014.03.002] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2013] [Revised: 03/03/2014] [Accepted: 03/03/2014] [Indexed: 10/25/2022]
Abstract
BACKGROUND Since lymphocytes predominantly express delayed rectifier K(+)-channels (Kv1.3) that trigger lymphocyte activation, statins, which exert immunosuppressive effects, would affect the channel currents. METHODS Employing the patch-clamp technique in murine thymocytes, we examined the effects of statins on Kv1.3-channel currents and the membrane capacitance (Cm). RESULTS Pravastatin significantly suppressed the pulse-end currents of the channels. Lovastatin and simvastatin also suppressed the peak currents, significantly decreasing the Cm. CONCLUSIONS This study demonstrated for the first time that statins inhibit thymocyte Kv1.3-channels. The slow inactivation patterns induced by lovastatin and simvastatin may be associated with their accumulation in the plasma membranes.
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Affiliation(s)
- Itsuro Kazama
- Department of Physiology I, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan.
| | - Asuka Baba
- Department of Physiology I, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan
| | - Yoshio Maruyama
- Department of Physiology I, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan
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14
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Kang S, Woo HH, Kim K, Lim KM, Noh JY, Lee MY, Bae YM, Bae ON, Chung JH. Dysfunction of vascular smooth muscle and vascular remodeling by simvastatin. Toxicol Sci 2014; 138:446-556. [PMID: 24449418 DOI: 10.1093/toxsci/kfu011] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Statins, inhibitors of 3-hydroxy-3-methylglutaryl-coenzyme A reductase, are widely prescribed for hypercholesterolemia. With the increasing use of statins, numerous reports demonstrated that statins can cause damage to skeletal muscles. However, the toxicities of statins on vascular smooth muscle, which are essential to cardiovascular homeostasis, have not been previously described. Here, we examined the effects of simvastatin on the contractile function and the integrity of vascular smooth muscle in isolated rat thoracic aortic rings, primary cultured vascular smooth muscle cells (VSMCs) in vitro and rats in vivo. In aortic rings, simvastatin suppressed the normal agonist-induced contractile responses in time- and concentration-dependent manners (0.86 g ± 0.11 at 10 μM simvastatin for 24 h compared with 1.89 g ± 0.11 at control). The suppression persisted in the endothelium-denuded aortic rings and was irreversible even after wash-out of simvastatin. Simvastatin suppressed the contraction induced by Bay K8644, an activator of voltage-operated Ca²⁺ channel (VOCC) in rat aortic rings and abolished agonist-induced intracellular Ca²⁺ increase in VSMCs. The simvastatin-induced contractile dysfunction was reversed by the supplementation of mevalonate and geranylgeranylpyrophosphate, precursors for protein isoprenylation. Consistently, activation of RhoA, a representative isoprenylated protein, was disrupted by simvastatin in VSMCs and RhoA-mediated phosphorylation of MYPT1 and CPI-17, and tonic tension were also suppressed. Notably, prolonged treatment of simvastatin up to 48 h induced apoptosis of vascular smooth muscle in aortic rings. Most importantly, simvastatin treatment in vivo significantly attenuated the agonist-induced vasoconstriction in rats ex vivo and induced a decrease in luminal area of the vascular wall. Collectively, these results demonstrate that simvastatin can impair the normal vascular contractility by disturbing Ca²⁺ influx and RhoA activity, ultimately leading to apoptosis and structural remodeling.
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Affiliation(s)
- Seojin Kang
- College of Pharmacy, Seoul National University, Seoul 151-742, Korea
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15
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Atochina-Vasserman EN, Goncharov DA, Volgina AV, Milavec M, James ML, Krymskaya VP. Statins in lymphangioleiomyomatosis. Simvastatin and atorvastatin induce differential effects on tuberous sclerosis complex 2-null cell growth and signaling. Am J Respir Cell Mol Biol 2013; 49:704-9. [PMID: 23947572 DOI: 10.1165/rcmb.2013-0203rc] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Mutations of the tumor suppressor genes tuberous sclerosis complex (TSC)1 and TSC2 cause pulmonary lymphangioleiomyomatosis (LAM) and tuberous sclerosis (TS). Current rapamycin-based therapies for TS and LAM have a predominantly cytostatic effect, and disease progression resumes with therapy cessation. Evidence of RhoA GTPase activation in LAM-derived and human TSC2-null cells suggests that 3-hydroxy-3-methylglutaryl-coenzyme A reductase inhibitor statins can be used as potential adjuvant agents. The goal of this study was to determine which statin (simvastatin or atorvastatin) is more effective in suppressing TSC2-null cell growth and signaling. Simvastatin, but not atorvastatin, showed a concentration-dependent (0.5-10 μM) inhibitory effect on mouse TSC2-null and human LAM-derived cell growth. Treatment with 10 μM simvastatin induced dramatic disruption of TSC2-null cell monolayer and cell rounding; in contrast, few changes were observed in cells treated with the same concentration of atorvastatin. Combined treatment of rapamycin with simvastatin but not with atorvastatin showed a synergistic growth-inhibitory effect on TSC2-null cells. Simvastatin, but not atorvastatin, inhibited the activity of prosurvival serine-threonine kinase Akt and induced marked up-regulation of cleaved caspase-3, a marker of cell apoptosis. Simvastatin, but not atorvastatin, also induced concentration-dependent inhibition of p42/p44 Erk and mTORC1. Thus, our data show growth-inhibitory and proapoptotic effects of simvastatin on TSC2-null cells compared with atorvastatin. These findings have translational significance for combinatorial therapeutic strategies of simvastatin to inhibit TSC2-null cell survival in TS and LAM.
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Affiliation(s)
- Elena N Atochina-Vasserman
- 1 Airway Biology Initiative, Pulmonary, Allergy & Critical Care Division, Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
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16
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Seto SW, Au ALS, Poon CCW, Zhang Q, Li RWS, Yeung JHK, Kong SK, Ngai SM, Wan S, Ho HP, Lee SMY, Hoi MPM, Chan SW, Leung GPH, Kwan YW. Acute simvastatin inhibits K ATP channels of porcine coronary artery myocytes. PLoS One 2013; 8:e66404. [PMID: 23799098 PMCID: PMC3684588 DOI: 10.1371/journal.pone.0066404] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2013] [Accepted: 05/06/2013] [Indexed: 01/19/2023] Open
Abstract
Background Statins (3-hydroxy-3-methyl-glutaryl coenzyme A (HMG-CoA) reductase inhibitors) consumption provides beneficial effects on cardiovascular systems. However, effects of statins on vascular KATP channel gatings are unknown. Methods Pig left anterior descending coronary artery and human left internal mammary artery were isolated and endothelium-denuded for tension measurements and Western immunoblots. Enzymatically-dissociated/cultured arterial myocytes were used for patch-clamp electrophysiological studies and for [Ca2+]i, [ATP]i and [glucose]o uptake measurements. Results The cromakalim (10 nM to 10 µM)- and pinacidil (10 nM to 10 µM)-induced concentration-dependent relaxation of porcine coronary artery was inhibited by simvastatin (3 and 10 µM). Simvastatin (1, 3 and 10 µM) suppressed (in okadaic acid (10 nM)-sensitive manner) cromakalim (10 µM)- and pinacidil (10 µM)-mediated opening of whole-cell KATP channels of arterial myocytes. Simvastatin (10 µM) and AICAR (1 mM) elicited a time-dependent, compound C (1 µM)-sensitive [3H]-2-deoxy-glucose uptake and an increase in [ATP]i levels. A time (2–30 min)- and concentration (0.1–10 µM)-dependent increase by simvastatin of p-AMPKα-Thr172 and p-PP2A-Tyr307 expression was observed. The enhanced p-AMPKα-Thr172 expression was inhibited by compound C, ryanodine (100 µM) and KN93 (10 µM). Simvastatin-induced p-PP2A-Tyr307 expression was suppressed by okadaic acid, compound C, ryanodine, KN93, phloridzin (1 mM), ouabain (10 µM), and in [glucose]o-free or [Na+]o-free conditions. Conclusions Simvastatin causes ryanodine-sensitive Ca2+ release which is important for AMPKα-Thr172 phosphorylation via Ca2+/CaMK II. AMPKα-Thr172 phosphorylation causes [glucose]o uptake (and an [ATP]i increase), closure of KATP channels, and phosphorylation of AMPKα-Thr172 and PP2A-Tyr307 resulted. Phosphorylation of PP2A-Tyr307 occurs at a site downstream of AMPKα-Thr172 phosphorylation.
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Affiliation(s)
- Sai Wang Seto
- The Vascular Biology Unit, Queensland Research Centre for Peripheral Vascular Disease, School of Medicine and Dentistry, James Cook University, Townsville, Queensland, Australia
- School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, Hong Kong, PR of China
| | - Alice Lai Shan Au
- School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, Hong Kong, PR of China
| | - Christina Chui Wa Poon
- School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, Hong Kong, PR of China
| | - Qian Zhang
- School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, Hong Kong, PR of China
| | - Rachel Wai Sum Li
- Department of Pharmacology and Pharmacy, Faculty of Medicine, The University of Hong Kong, Hong Kong, PR of China
| | - John Hok Keung Yeung
- School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, Hong Kong, PR of China
| | - Siu Kai Kong
- School of Life Sciences, Faculty of Science, The Chinese University of Hong Kong, Shatin, Hong Kong, PR of China
| | - Sai Ming Ngai
- School of Life Sciences, Faculty of Science, The Chinese University of Hong Kong, Shatin, Hong Kong, PR of China
| | - Song Wan
- Department of Surgery, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, Hong Kong, PR of China
| | - Ho Pui Ho
- Department of Electronic Engineering, Faculty of Engineering, The Chinese University of Hong Kong, Shatin, Hong Kong, PR of China
| | - Simon Ming Yuen Lee
- Institute of Chinese Medical Sciences, the University of Macau, Macau, PR of China
| | - Maggie Pui Man Hoi
- Institute of Chinese Medical Sciences, the University of Macau, Macau, PR of China
| | - Shun Wan Chan
- State Key Laboratory of Chinese Medicine and Molecular Pharmacology, Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Kowloon, Hong Kong, PR of China
- * E-mail: (YWK); (GPHL); (SWC)
| | - George Pak Heng Leung
- Department of Pharmacology and Pharmacy, Faculty of Medicine, The University of Hong Kong, Hong Kong, PR of China
- * E-mail: (YWK); (GPHL); (SWC)
| | - Yiu Wa Kwan
- School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, Hong Kong, PR of China
- * E-mail: (YWK); (GPHL); (SWC)
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Kanaki AI, Sarafidis PA, Georgianos PI, Kanavos K, Tziolas IM, Zebekakis PE, Lasaridis AN. Effects of low-dose atorvastatin on arterial stiffness and central aortic pressure augmentation in patients with hypertension and hypercholesterolemia. Am J Hypertens 2013; 26:608-16. [PMID: 23449607 DOI: 10.1093/ajh/hps098] [Citation(s) in RCA: 75] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
BACKGROUND Experimental and clinical data suggest that statins exert anti-inflammatory and antiproliferative actions on vasculature beyond their lipid-lowering properties. Whether these pleiotropic effects of statins translate into a beneficial effect on arterial stiffness is not clear. This study aimed to evaluate the potential effects of low-dose atorvastatin treatment on arterial stiffness and central arterial pressure waveforms in patients with mild hypertension and hypercholesterolemia. METHODS In a double-blind, randomized, placebo-controlled fashion, 50 hypertensive and hypercholesterolemic patients were allocated to receive 10 mg of atorvastatin or placebo for 26 weeks. Arterial stiffness was assessed by aortic pulse-wave velocity (PWV) using a Sphygmocor device. Central arterial pressure waveform parameters were estimated by radial artery applanation tonometry. Heart rate-adjusted augmentation index (AIx(75)) was used as measure of wave reflections. RESULTS At study end, aortic PWV (9.0 ± 1.5 vs. 10.9 ± 2.6 m/sec; P < 0.001) and AIx(75) (24.9% ± 9.7% vs 28.8% ± 11.8%; P < 0.001) were significantly lower in the atorvastatin group than that placebo group. Furthermore, decreases in central aortic systolic blood pressure and pulse pressure were evident at study-end with atorvastatin but not with placebo (130 ± 8 vs. 138 ± 6 mm Hg, P < 0.001; 48 ± 7 vs. 53 ± 6 mm Hg, P < 0.05, respectively). Atorvastatin-induced reductions in aortic PWV during follow-up showed significant associations with changes in AIx(75) and central aortic systolic blood pressure and pulse pressure. CONCLUSIONS This study shows that low-dose atorvastatin treatment improves arterial stiffness and exerts a reduction on central aortic pressures. These effects may represent a potential mechanism of cardiovascular risk reduction observed with statin use. CLINICAL TRIAL REGISTRATION ClinicalTrials.gov Database Identifier Number: NCT01126684.
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Affiliation(s)
- Aggeliki I Kanaki
- Section of Nephrology and Hypertension, 1st Department of Medicine, AHEPA University Hospital, Thessaloniki, Greece
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Tasat DR, Yakisich JS. Expanding the pleiotropic effects of statins: attenuation of air pollution-induced inflammatory response. Am J Physiol Lung Cell Mol Physiol 2012; 303:L640-1. [PMID: 22923638 DOI: 10.1152/ajplung.00280.2012] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
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19
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Uhiara CO, Alexander SPH, Roberts RE. Simvastatin evokes an unpredicted inhibition of β-adrenoceptor-mediated vasodilatation in porcine coronary artery. Eur J Pharmacol 2012; 690:158-63. [PMID: 22796645 DOI: 10.1016/j.ejphar.2012.07.006] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2012] [Revised: 06/27/2012] [Accepted: 07/03/2012] [Indexed: 11/26/2022]
Abstract
HMG-CoA reductase inhibitors, or statins, are widely used as cholesterol-lowering agents in the treatment of dyslipidemias. Statins have also been reported to have pleiotropic effects, independent of their effects on cholesterol synthesis, possibly through inhibition of the monomeric G proteins Ras and Rho, which are able to signal through ERK and Rho kinase activities, respectively. We have previously demonstrated that inhibition of ERK activation enhances β-adrenoceptor-mediated vasodilatation in the porcine isolated coronary artery. As statins can also inhibit ERK activation, the initial aim of this study was to determine whether statins have a similar influence on β-adrenoceptor-evoked vasodilatation. Segments of porcine distal coronary artery were mounted in a Mulvany wire myograph and bathed in Krebs-Henseleit buffer gassed with 95% O(2)/5% CO(2) and maintained at 37 °C. Tissues were pre-contracted with the thromboxane mimetic U46619 prior to cumulative concentration-response curves to the β-adrenoceptor agonist salbutamol in the absence or presence of simvastatin (1, 5 or 10 μM), pravastatin (10 μM), or lovastatin (10 μM). Simvastatin inhibited the salbutamol-induced relaxation of the coronary artery. Similar effects were seen with lovastatin, but not pravastatin or the sodium salt of simvastatin. Simvastatin, but not pravastatin also inhibited the relaxations to the Ca(2+)-activated K(+) channel opener NS1619 and the K(ATP) channel opener pinacidil. Unexpectedly, these data indicate that, rather than enhancing β-adrenoceptor-mediated vasodilatation, lipophilic statins impair these responses. This is likely to be due to effects on K(+) channels.
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Affiliation(s)
- Chukwuemeka O Uhiara
- School of Biomedical Sciences, University of Nottingham, Nottingham NG7 2UH, United Kingdom
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20
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Kanaki AI, Sarafidis PA, Georgianos PI, Stafylas PC, Kanavos K, Tziolas IM, Lasaridis AN. Low-dose atorvastatin reduces ambulatory blood pressure in patients with mild hypertension and hypercholesterolaemia: a double-blind, randomized, placebo-controlled study. J Hum Hypertens 2011; 26:577-84. [DOI: 10.1038/jhh.2011.80] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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21
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Liu YJ, Wang XG, Tang YB, Chen JH, Lv XF, Zhou JG, Guan YY. Simvastatin Ameliorates Rat Cerebrovascular Remodeling During Hypertension via Inhibition of Volume-Regulated Chloride Channel. Hypertension 2010; 56:445-52. [DOI: 10.1161/hypertensionaha.110.150102] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Affiliation(s)
- Yu-Jie Liu
- From the Department of Pharmacology (Y.-J.L., X.-G.W., Y.-B.T., J.-H.C., X.-F.L., J.-G.Z., Y.-Y.G.), Cardiac and Cerebral Vascular Research Center (Y.-J.L., X.-G.W., Y.-B.T., X.-F.L., J.-G.Z., Y.-Y.G.), Zhongshan School of Medcine, Sun Yat-Sen University, Guangzhou, People’s Republic of China; Department of Anaesthesia (J.-H.C.), Third Affiliated Hospital, Sun Yat-Sen University, Guangzhou, People’s Republic of China
| | - Xiao-Guang Wang
- From the Department of Pharmacology (Y.-J.L., X.-G.W., Y.-B.T., J.-H.C., X.-F.L., J.-G.Z., Y.-Y.G.), Cardiac and Cerebral Vascular Research Center (Y.-J.L., X.-G.W., Y.-B.T., X.-F.L., J.-G.Z., Y.-Y.G.), Zhongshan School of Medcine, Sun Yat-Sen University, Guangzhou, People’s Republic of China; Department of Anaesthesia (J.-H.C.), Third Affiliated Hospital, Sun Yat-Sen University, Guangzhou, People’s Republic of China
| | - Yong-Bo Tang
- From the Department of Pharmacology (Y.-J.L., X.-G.W., Y.-B.T., J.-H.C., X.-F.L., J.-G.Z., Y.-Y.G.), Cardiac and Cerebral Vascular Research Center (Y.-J.L., X.-G.W., Y.-B.T., X.-F.L., J.-G.Z., Y.-Y.G.), Zhongshan School of Medcine, Sun Yat-Sen University, Guangzhou, People’s Republic of China; Department of Anaesthesia (J.-H.C.), Third Affiliated Hospital, Sun Yat-Sen University, Guangzhou, People’s Republic of China
| | - Jing-Hui Chen
- From the Department of Pharmacology (Y.-J.L., X.-G.W., Y.-B.T., J.-H.C., X.-F.L., J.-G.Z., Y.-Y.G.), Cardiac and Cerebral Vascular Research Center (Y.-J.L., X.-G.W., Y.-B.T., X.-F.L., J.-G.Z., Y.-Y.G.), Zhongshan School of Medcine, Sun Yat-Sen University, Guangzhou, People’s Republic of China; Department of Anaesthesia (J.-H.C.), Third Affiliated Hospital, Sun Yat-Sen University, Guangzhou, People’s Republic of China
| | - Xiao-Fei Lv
- From the Department of Pharmacology (Y.-J.L., X.-G.W., Y.-B.T., J.-H.C., X.-F.L., J.-G.Z., Y.-Y.G.), Cardiac and Cerebral Vascular Research Center (Y.-J.L., X.-G.W., Y.-B.T., X.-F.L., J.-G.Z., Y.-Y.G.), Zhongshan School of Medcine, Sun Yat-Sen University, Guangzhou, People’s Republic of China; Department of Anaesthesia (J.-H.C.), Third Affiliated Hospital, Sun Yat-Sen University, Guangzhou, People’s Republic of China
| | - Jia-Guo Zhou
- From the Department of Pharmacology (Y.-J.L., X.-G.W., Y.-B.T., J.-H.C., X.-F.L., J.-G.Z., Y.-Y.G.), Cardiac and Cerebral Vascular Research Center (Y.-J.L., X.-G.W., Y.-B.T., X.-F.L., J.-G.Z., Y.-Y.G.), Zhongshan School of Medcine, Sun Yat-Sen University, Guangzhou, People’s Republic of China; Department of Anaesthesia (J.-H.C.), Third Affiliated Hospital, Sun Yat-Sen University, Guangzhou, People’s Republic of China
| | - Yong-Yuan Guan
- From the Department of Pharmacology (Y.-J.L., X.-G.W., Y.-B.T., J.-H.C., X.-F.L., J.-G.Z., Y.-Y.G.), Cardiac and Cerebral Vascular Research Center (Y.-J.L., X.-G.W., Y.-B.T., X.-F.L., J.-G.Z., Y.-Y.G.), Zhongshan School of Medcine, Sun Yat-Sen University, Guangzhou, People’s Republic of China; Department of Anaesthesia (J.-H.C.), Third Affiliated Hospital, Sun Yat-Sen University, Guangzhou, People’s Republic of China
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Shi CY, Wang R, Liu CX, Jiang H, Ma ZY, Li L, Zhang W. Simvastatin inhibits acidic extracellular pH-activated, outward rectifying chloride currents in RAW264.7 monocytic-macrophage and human peripheral monocytes. Int Immunopharmacol 2008; 9:247-52. [PMID: 19084616 DOI: 10.1016/j.intimp.2008.11.011] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2008] [Revised: 11/17/2008] [Accepted: 11/20/2008] [Indexed: 11/29/2022]
Abstract
Extracellular acidic pH activated chloride channels (I(Cl,acid)) have been characterized in HEK 293 cells and mammalian cardiac myocytes. This study was designed to evaluate the expression of I(Cl,acid) in RAW264.7 monocytic-macrophage and human peripheral monocytes and to investigate the effect of simvastatin on I(Cl,acid). In two kinds of cells, the activation and deactivation of the current rapidly and repeatedly followed the change of the extracellular solution to pH=4.3. Compared with the outward current (pA/pF) activated at pH 4.3, the currents inhibited by simvastatin at concentrations of 0.1 microM were all decreased a little, however the currents at concentrations of 1 microM and 10 microM simvastatin were decreased significantly. The IC(50) for simvastatin inhibiting I(Cl,acid) of RAW264.7 was 13.77 microM. In summary, we report for the first time that simvastatin inhibits the I(Cl,acid) of RAW264.7 monocytic-macrophage and human peripheral monocytes in a concentration-dependent manner.
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Affiliation(s)
- Cheng-Yao Shi
- Department of Pharmacy, QiLu Hospital, Shandong University, Jinan 250012, China
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23
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Matsuda T, Toyohira Y, Ueno S, Tsutsui M, Yanagihara N. Simvastatin inhibits catecholamine secretion and synthesis induced by acetylcholine via blocking Na+ and Ca2+ influx in bovine adrenal medullary cells. J Pharmacol Exp Ther 2008; 327:130-6. [PMID: 18593956 DOI: 10.1124/jpet.108.139659] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Simvastatin, an inhibitor of HMG-CoA reductase, is a potent inhibitor of cholesterol biosynthesis and has beneficial effects in the primary and secondary prevention of cardiovascular diseases. In this study, we report the effects of simvastatin on catecholamine secretion and synthesis in cultured bovine adrenal medullary cells used as a model of sympathetic neurons. Simvastatin inhibited catecholamine secretion induced by acetylcholine, an agonist of the nicotinic acetylcholine receptor; by veratridine, an activator of voltage-dependent Na(+) channels; and by high K(+), an activator of voltage-dependent Ca(2+) channels (IC(50) = 3.8, 7.8, and 6.1 microM, respectively). Simvastatin also suppressed acetylcholine-induced (22)Na(+) influx (IC(50) = 4.3 microM) and (45)Ca(2+) influx (IC(50) = 6.1 microM), veratridine-induced (22)Na(+) influx (IC(50) = 6.6 microM) and (45)Ca(2+) influx (IC(50) = 12 microM), and high K(+)-induced (45)Ca(2+) influx (IC(50) = 11 microM). The reduction of catecholamine secretion caused by simvastatin was not overcome by increasing the concentration of acetylcholine or by treatment with mevalonate, the first metabolite of HMG-CoA. The inhibitory effect of simvastatin on histamine-induced secretion of catecholamines was observed in the presence of extracellular Ca(2+), but not in a Ca(2+)-free medium, suggesting that simvastatin does not interfere with histamine receptors nonselectively. Simvastatin also suppressed acetylcholine-induced [(14)C]catecholamine synthesis from [(14)C]tyrosine as well as tyrosine hydroxylase activity. These findings suggest that simvastatin inhibits catecholamine secretion and synthesis induced by acetylcholine through suppression of Na(+) and Ca(2+) influx in the adrenal medulla and probably in the sympathetic neurons.
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Affiliation(s)
- Taeko Matsuda
- Department of Pharmacology, University of Occupational and Environmental Health, School of Medicine, 1-1 Iseigaoka, Yahatanishi-ku, Kitakyushu 807-8555, Japan
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Abstract
There is increasing evidence that statins reduce cardiovascular events such as coronary artery disease or stroke in hypercholesterolemic patients in both primary and secondary prevention. The striking benefit achieved with statin treatments in patients with a wide range of cholesterol levels cannot be attributed to their cholesterol lowering effect alone. Substantial data has recently accumulated showing that statins exert various effects on multiple targets, namely pleiotropic effects, especially targeting the concept of 'vascular failure', including the improvement of vascular endothelial function, inhibition of vascular smooth muscle cell proliferation and migration, anti-inflammatory actions, anti-oxidative effects or stabilization of vulnerable plaques. These effects have potential in the treatments of coronary artery disease in various settings, such as prevention of its onset as well as its progression, or plaque rupture. Statin therapy should be more extensively applied even in normolipidemic patients if there are additional risk factors such as hypertension, diabetes mellitus, or others. Furthermore, statins may be used to intervene in earlier stage risk conditions such as postprandial hyperlipidemia or hyperglycemia, insulin resistant state, masked hypertension, or metabolic syndrome to further reduce mortality or morbidity of coronary artery disease and heart failure.
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Affiliation(s)
- Teruo Inoue
- Department of Cardiovascular and Renal Medicine, Saga University Faculty of Medicine, 5-1-1 Nabeshima, Saga 849-8501, Japan.
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Seto SW, Au ALS, Lam TY, Chim SSC, Lee SMY, Wan S, Tjiu DCS, Shigemura N, Yim APC, Chan SW, Tsui SKW, Leung GPH, Kwan YW. Modulation by simvastatin of iberiotoxin-sensitive, Ca2+-activated K+ channels of porcine coronary artery smooth muscle cells. Br J Pharmacol 2007; 151:987-97. [PMID: 17558433 PMCID: PMC2042927 DOI: 10.1038/sj.bjp.0707327] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND AND PURPOSE Statins (3-hydroxy-3-methyl-glutaryl coenzyme A (HMG CoA) reductase inhibitors) have been demonstrated to reduce cardiovascular mortality. It is unclear how the expression level of HMG CoA reductase in cardiovascular tissues compares with that in cells derived from the liver. We hypothesized that this enzyme exists in different cardiovascular tissues, and simvastatin modulates the vascular iberiotoxin-sensitive Ca2+-activated K(+) (BK(Ca)) channels. EXPERIMENTAL APPROACHES Expression of HMG CoA reductase in different cardiovascular preparations was measured. Effects of simvastatin on BK(Ca) channel gatings of porcine coronary artery smooth muscle cells were evaluated. KEY RESULTS Western immunoblots revealed the biochemical existence of HMG CoA reductase in human cardiovascular tissues and porcine coronary artery. In porcine coronary artery smooth muscle cells, extracellular simvastatin (1, 3 and 10 microM) (hydrophobic), but not simvastatin Na+ (hydrophilic), inhibited the BK(Ca) channels with a minimal recovery upon washout. Isopimaric acid (10 microM)-mediated enhancement of the BK(Ca) amplitude was reversed by external simvastatin. Simvastatin Na+ (10 microM, applied internally), markedly attenuated isopimaric acid (10 microM)-induced enhancement of the BK(Ca) amplitude. Reduced glutathione (5 mM; in the pipette solution) abolished simvastatin -elicited inhibition. Mevalonolactone (500 microM) and geranylgeranyl pyrophosphate (20 microM) only prevented simvastatin (1 and 3 microM)-induced responses. simvastatin (10 microM ) caused a rottlerin (1 microM)-sensitive (cycloheximide (10 microM)-insensitive) increase of PKC-delta protein expression. CONCLUSIONS AND IMPLICATIONS Our results demonstrated the biochemical presence of HMG CoA reductase in different cardiovascular tissues, and that simvastatin inhibited the BK(Ca) channels of the arterial smooth muscle cells through multiple intracellular pathways.
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MESH Headings
- Adult
- Aged
- Animals
- Blotting, Western
- Caveolin 1/biosynthesis
- Cell Line
- Cell Line, Tumor
- Coronary Vessels/cytology
- Coronary Vessels/drug effects
- Coronary Vessels/physiology
- Dose-Response Relationship, Drug
- Enzyme Activation/drug effects
- Female
- Humans
- Hydroxymethylglutaryl-CoA Reductase Inhibitors/pharmacology
- Imidazoles/pharmacology
- In Vitro Techniques
- Male
- Membrane Potentials/drug effects
- Middle Aged
- Muscle, Smooth, Vascular/cytology
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/physiology
- Myocytes, Smooth Muscle/drug effects
- Myocytes, Smooth Muscle/metabolism
- Myocytes, Smooth Muscle/physiology
- Peptides/pharmacology
- Phorbol Esters/pharmacology
- Potassium Channels, Calcium-Activated/antagonists & inhibitors
- Potassium Channels, Calcium-Activated/metabolism
- Potassium Channels, Calcium-Activated/physiology
- Protein Kinase C-delta/metabolism
- Pyridines/pharmacology
- Simvastatin/chemistry
- Simvastatin/pharmacology
- Swine
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Affiliation(s)
- S W Seto
- Department of Pharmacology, Faculty of Medicine, Prince of Wales Hospital, The Chinese University of Hong Kong Hong Kong, PR China
| | - A L S Au
- Department of Pharmacology, Faculty of Medicine, Prince of Wales Hospital, The Chinese University of Hong Kong Hong Kong, PR China
| | - T Y Lam
- Department of Pharmacology, Faculty of Medicine, Prince of Wales Hospital, The Chinese University of Hong Kong Hong Kong, PR China
| | - S S C Chim
- Department of Obstetrics and Gynaecology, Faculty of Medicine, Prince of Wales Hospital, The Chinese University of Hong Kong Hong Kong, PR China
| | - S M Y Lee
- Institute of Chinese Medical Sciences, University of Macau Macau, PR China
| | - S Wan
- Department of Surgery, Faculty of Medicine, Prince of Wales Hospital, The Chinese University of Hong Kong Hong Kong, PR China
| | - D C S Tjiu
- Department of Surgery, United Christian Hospital, The Hong Kong Polytechnic University Hong Kong SAR, PR China
| | - N Shigemura
- Department of Surgery, Faculty of Medicine, Prince of Wales Hospital, The Chinese University of Hong Kong Hong Kong, PR China
| | - A P C Yim
- Department of Surgery, Faculty of Medicine, Prince of Wales Hospital, The Chinese University of Hong Kong Hong Kong, PR China
| | - S W Chan
- Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University Hong Kong SAR, PR China
| | - S K W Tsui
- Department of Biochemistry, Faculty of Medicine, Prince of Wales Hospital, The Chinese University of Hong Kong Hong Kong SAR, PR China
| | - G P H Leung
- Department of Pharmacology, University of Hong Kong Hong Kong SAR, PR China
| | - Y W Kwan
- Department of Pharmacology, Faculty of Medicine, Prince of Wales Hospital, The Chinese University of Hong Kong Hong Kong, PR China
- Author for correspondence:
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26
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Son BK, Kozaki K, Iijima K, Eto M, Kojima T, Ota H, Senda Y, Maemura K, Nakano T, Akishita M, Ouchi Y. Statins protect human aortic smooth muscle cells from inorganic phosphate-induced calcification by restoring Gas6-Axl survival pathway. Circ Res 2006; 98:1024-31. [PMID: 16556867 DOI: 10.1161/01.res.0000218859.90970.8d] [Citation(s) in RCA: 154] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Vascular calcification is clinically important in the development of cardiovascular disease. It is reported that hydroxy-3-methylglutaryl coenzyme A (HMG CoA) reductase inhibitors (statins) inhibited vascular calcification in several clinical trials. However, the mechanism is poorly understood. Recently, it has been suggested that apoptosis is one of the important processes regulating vascular smooth muscle cell (VSMC) calcification. In this study, we investigated the effect of statins on VSMC calcification by testing their effect on apoptosis, focusing in particular on regulation of the survival pathway mediated by growth arrest-specific gene 6 (Gas6), a member of the vitamin K-dependent protein family, and its receptor, Axl. In human aortic smooth muscle cells (HASMC), statins significantly inhibited inorganic phosphate (Pi)-induced calcification in a concentration-dependent manner (reduced by 49% at 0.1 micromol/L atorvastatin). The inhibitory effect of statins was mediated by preventing apoptosis, which was increased by Pi in a concentration-dependent manner, and not by inhibiting sodium-dependent phosphate cotransporter (NPC) activity, another mechanism regulating HASMC calcification. Furthermore, the antiapoptotic effect of statins was dependent on restoration of Gas6, whose expression was downregulated by Pi. Restoration of Gas6 mRNA by statins was mediated by mRNA stabilization, and not by an increase in transcriptional activity. Suppression of Gas6 using small interfering RNA and the Axl-extracellular domain abolished the preventive effect of statins on Pi-induced apoptosis and calcification. These data demonstrate that statins protected HASMC from Pi-induced calcification by inhibiting apoptosis via restoration of the Gas6-Axl pathway.
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Affiliation(s)
- Bo-Kyung Son
- Department of Geriatric Medicine, Graduate School of Medicine, The University of Tokyo, Tokyo 113-8655, Japan
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27
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Mraiche F, Cena J, Das D, Vollrath B. Effects of statins on vascular function of endothelin-1. Br J Pharmacol 2005; 144:715-26. [PMID: 15678081 PMCID: PMC1576052 DOI: 10.1038/sj.bjp.0706114] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
1. Although statins have been reported to inhibit the prepro-endothelin-1 (ET-1) gene transcription in endothelial cells, their effects on the vascular function of ET-1 have not been explored. We, therefore, examined the effects of statins on contraction and DNA synthesis mediated by ET-1 in vascular smooth muscle. The effects of statins on contraction induced by ET-1 were compared to those mediated by noradrenaline (NA) and KCl. 2. Simvastatin (SV) induced a concentration-dependent relaxation of tonic contraction mediated by ET-1 (10 nM) (IC50 value of 1.3 microM). The relaxation was also observed in rings precontracted with NA (0.1 microM) and KCl (60 mM). In contrast, pravastatin did not have any effect on the contractions. 3. Endothelial denudation or pretreatment with L-NAME did not prevent the relaxation, but did reduce the relaxant activity of SV. 4. SV prevented Rho activation caused by ET-1 and KCl in aortic homogenates, as assessed by a Rho pulldown assay. 5. The Rho kinase inhibitor HA-1077 mimicked the effects of SV on tonic contractions induced by ET-1, NA and KCl. 6. Pretreatment with the Kv channels inhibitor, 4-aminopyridine, attenuated the ability of SV to relax contractions mediated by ET-1 and NA. 7. In quiescent VSM cells, SV significantly inhibited DNA synthesis and Rho translocation stimulated by ET-1, as assessed by [3H]thymidine incorporation and Western blot, respectively. 8. Inhibition of Rho geranylgeranylation by GGTI-297, or treatment with HA-1077, mimicked the effects of SV on DNA synthesis stimulated by ET-1. 9. The results show that the statin potently inhibits both ET-1-mediated contraction and DNA synthesis via multiple mechanisms. Clinical benefits of statins may result, in part, from their effects on vascular function of ET-1.
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Affiliation(s)
- Fatima Mraiche
- Department of Pharmacology, Faculty of Medicine, University of Alberta, Edmonton, Alberta, Canada T6G 2H7
| | - Jonathan Cena
- Department of Pharmacology, Faculty of Medicine, University of Alberta, Edmonton, Alberta, Canada T6G 2H7
| | - Debarsi Das
- Department of Pharmacology, Faculty of Medicine, University of Alberta, Edmonton, Alberta, Canada T6G 2H7
| | - Bozena Vollrath
- Department of Pharmacology, Faculty of Medicine, University of Alberta, Edmonton, Alberta, Canada T6G 2H7
- Author for correspondence:
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28
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Pérez-Guerrero C, Márquez-Martín A, Herrera MD, Marhuenda E, Alvarez de Sotomayor M. Regulation of Vascular Tone from Spontaneously Hypertensive Rats by the HMG-CoA Reductase Inhibitor, Simvastatin. Pharmacology 2005; 74:209-15. [PMID: 15920353 DOI: 10.1159/000085957] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2005] [Accepted: 03/29/2005] [Indexed: 12/14/2022]
Abstract
The acute effect of simvastatin on aortic rings from spontaneously hypertensive rats (SHRs) was identified. Simvastatin-evoked relaxations of both depolarized and phenylephrine-precontracted arteries were independent of the presence of endothelium. This effect was inhibited by diltiazem and mevalonate, but not by the Rho-kinase inhibitor, Y-27632. Simvastatin prevented contraction induced by phenylephrine, calcium ionophore A-23187 and CaCl2 in Ca2+-free medium. Y-27632 decreased the effect of simvastatin. On the contrary, contraction induced by noradrenaline in Ca2+-free medium was not affected. These results suggest that simvastatin elicited an effect on vascular smooth muscle cells from SHRs that may involve blockade of extracellular calcium entry and decrease vascular contraction by affecting Rho-kinase.
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29
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Pouvreau S, Berthier C, Blaineau S, Amsellem J, Coronado R, Strube C. Membrane cholesterol modulates dihydropyridine receptor function in mice fetal skeletal muscle cells. J Physiol 2004; 555:365-81. [PMID: 14724204 PMCID: PMC1664851 DOI: 10.1113/jphysiol.2003.055285] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2004] [Accepted: 01/05/2004] [Indexed: 11/08/2022] Open
Abstract
Caveolae and transverse (T-) tubules are membrane structures enriched in cholesterol and glycosphingolipids. They play an important role in receptor signalling and myogenesis. The T-system is also highly enriched in dihydropyridine receptors (DHPRs), which control excitation-contraction (E-C) coupling. Recent results have shown that a depletion of membrane cholesterol alters caveolae and T-tubules, yet detailed functional studies of DHPR expression are lacking. Here we studied electrophysiological and morphological effects of methyl-beta-cyclodextrin (MbetaCD), a cholesterol-sequestering drug, on freshly isolated fetal skeletal muscle cells. Exposure of fetal myofibres to 1-3 mM MbetaCD for 1 h at 37 degrees C led to a significant reduction in caveolae and T-tubule areas and to a decrease in cell membrane electrical capacitance. In whole-cell voltage-clamp experiments, the L-type Ca(2+) current amplitude was significantly reduced, and its voltage dependence was shifted approximately 15 mV towards more positive potentials. Activation and inactivation kinetics were slower in treated cells than in control cells and stimulation by a saturating concentration of Bay K 8644 was enhanced. In addition, intramembrane charge movement and Ca(2+) transients evoked by a depolarization were reduced without a shift of the midpoint, indicating a weakening of E-C coupling. In contrast, T-type Ca(2+) current was not affected by MbetaCD treatment. Most of the L-type Ca(2+) conductance reduction and E-C coupling weakening could be explained by a decrease of the number of DHPRs due to the disruption of caveolae and T-tubules. However, the effects on L-type channel gating kinetics suggest that membrane cholesterol content modulates DHPR function. Moreover, the significant shift of the voltage dependence of L-type current without any change in the voltage dependence of charge movement and Ca(2+) transients suggests that cholesterol differentially regulates the two functions of the DHPR.
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Affiliation(s)
- Sandrine Pouvreau
- LNPC, CNRS UMR 6150, Faculté Médecine Nord, Bd Pierre Dramard, 13916 Marseille Cedex 20, France
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