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1.
Curr Drug Discov Technol ; 20(3): e240223214005, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36825708

RESUMO

INTRODUCTION: Diabetes is the most common component of metabolic syndrome, including abdominal obesity, insulin resistance, hypertension, and dyslipoproteinemia. OBJECTIVE: This study aims to determine whether vanillic acid has antihyperlipidemic properties in diabetic hypertensive rats. METHODS: For this study healthy male albino Wister rats (180-220 gm) were selected. A 20-week highfat diet (HFD) was given to produce diabetic hypertension in Wister rats. Control and diabetic hypertensive rats were treated with vanillic acid. Vanillic acid effects on lipid profiles (cholesterol, triglycerides, phospholipids, free fatty acids, high-density lipoproteins (HDL)) and lipid metabolizing enzymes LPL, LCAT, and HMG CoA reductase studied by a conventional method. To understand the effect of vanillic acid control, experimental rat lipid and metabolic enzymes were studied and treated and controlled animal liver tissues were observed using the different histology staining agents. RESULTS: Vanillic acid caused considerable lipid profile reductions except for HDL and increased plasma HDL levels. After eight weeks of vanillic acid administration also boosts lipid marker enzyme activity (HMG CoA reductase, LPL, and LCAT). In addition, vanillic acid reduces the accumulation of collagen in liver tissues. CONCLUSION: These research studies suggest that vanillic acid has antihyperlipidemic effects in diabetic hypertensive rats fed an HFD.


Assuntos
Diabetes Mellitus , Hipertensão , Ratos , Masculino , Animais , Dieta Hiperlipídica/efeitos adversos , Ácido Vanílico/farmacologia , Ácido Vanílico/uso terapêutico , Ácido Vanílico/metabolismo , Ratos Wistar , Fígado , Hipolipemiantes/farmacologia , Hipolipemiantes/uso terapêutico , Colesterol/metabolismo , Hidroximetilglutaril-CoA Redutases/metabolismo , Hidroximetilglutaril-CoA Redutases/farmacologia , Diabetes Mellitus/metabolismo
2.
J Ethnopharmacol ; 292: 115237, 2022 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-35351574

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Dillenia indica L. is an edible plant from the Dilleniaceae family present in the forest of India and other Asian countries. Different parts of this plant are being used in the traditional system of medicines for various diseases like diabetes, indigestion, asthma, jaundice, and rheumatic pain by various rural communities. This plant is very common among Khamptis traditional healers, the rural community of the Dhemaji district of Assam, ethnic communities of Dibru-Saikhowa Biosphere Reserve of Northeast, India for various medicinal uses. It is observed as a 'vat' suppressant and 'pitta' boosting medicine in Ayurveda. AIM OF THE STUDY: The aim of this research was to evaluate the effect of hydroethanolic extract of Dillenia indica leaf (DI-HET) against non-alcoholic fatty liver disease (NAFLD) as it is reported effective against jaundice in traditional medicine. We are also planning to see the various molecular mechanisms responsible for its effect if it is efficacious. STUDY DESIGN/METHOD: An in vitro model for NAFLD was employed in this study. For this HepG2 cells were incubated with 100 µM of oleic acid (OA) for 24 h. For evaluation of the effect of DI-HET, the extracts (5 or 10 µg/mL) were pretreated to the OA group. Fenofibrate was the positive control. Various parameters relevant to lipogenesis and ß-oxidation of fatty acids like intracellular lipid accumulation, reactive oxygen species (ROS), mitochondrial stress, and key proteins were studied. RESULTS: DI-HET significantly reduced the intracellular lipid accumulation in OA treated cells. And also substantially decreased the expression of lipogenic proteins and increased ß-oxidation in the OA group. OA induced ROS generation was found to reduce with DI-HET treatment. Western blot analysis showed that the expression of LXR-α, SREBP-1C, SREBP-2, HMGCR, FAS, CD-36, and ACOX-1 were downregulated while that of SIRT-1, p-LKB-, p-AMPK, p-ACC, CPT-1, and PPAR-α upregulated in DI-HET treatment. LCMS/MS analysis showed the presence of polyphenols like naringenin, catechin, epicatechin, shikimic acid, syringic acid, vanillic acid, and kaempferol. CONCLUSION: These results suggest that DI-HET is effective against NAFLD by activation of the SIRT-1/p-LKB-1/AMPK signaling pathway via polyphenols present in the extract.


Assuntos
Dilleniaceae , Hepatopatia Gordurosa não Alcoólica , Sirtuínas , Proteínas Quinases Ativadas por AMP/metabolismo , Dilleniaceae/metabolismo , Células Hep G2 , Humanos , Hidroximetilglutaril-CoA Redutases/metabolismo , Hidroximetilglutaril-CoA Redutases/farmacologia , Hidroximetilglutaril-CoA Redutases/uso terapêutico , Metabolismo dos Lipídeos , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/metabolismo , Ácido Oleico/farmacologia , PPAR alfa/metabolismo , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Polifenóis/farmacologia , Espécies Reativas de Oxigênio , Transdução de Sinais , Sirtuínas/metabolismo
3.
FEBS Open Bio ; 10(5): 927-936, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32237049

RESUMO

In organ transplantation, donor-specific HLA antibody (DSA) is considered a major cause of graft rejection. Because DSA targets primarily donor-specific human leukocyte antigen (HLA) expressed on graft endothelial cells, the prevention of its expression is a possible strategy for avoiding or salvaging DSA-mediated graft rejection. We examined the effect of various clinically used drugs on HLA class II expression on endothelial cells. Interferon-γ (IFN-γ)-induced HLA class II DR (HLA-DR) was downregulated by everolimus (EVR, 49.1% ± 0.8%; P < 0.01) and fluvastatin (FLU, 33.8% ± 0.6%; P < 0.01). Moreover, the combination of EVR and FLU showed a greater suppressive effect on HLA-DR expression. In contrast, cyclosporine, tacrolimus, mycophenolic acid, and prednisolone did not exhibit any significant suppressive effect. FLU, but not EVR, suppressed mRNA of HLA-DR. Imaging analysis revealed that HLA-DR expressed in cytosol or on the cell surface was repressed by EVR (cytosol: 58.6% ± 4.9%, P < 0.01; cell surface: 80.9% ± 4.0%, P < 0.01) and FLU (cytosol: 19.0% ± 3.4%, P < 0.01; cell surface: 48.3% ± 4.8%, P < 0.01). These data indicated that FLU and EVR suppressed IFN-γ-induced HLA-DR expression at the transcriptional and post-translational level, respectively, suggesting a potential approach for alleviating DSA-related issues in organ transplantation.


Assuntos
Antígenos HLA-DR/biossíntese , Antígenos HLA-DR/genética , Linhagem Celular , Células Endoteliais/metabolismo , Everolimo/farmacologia , Fluvastatina/farmacologia , Expressão Gênica/efeitos dos fármacos , Expressão Gênica/genética , Rejeição de Enxerto/imunologia , Antígenos HLA/imunologia , Antígenos HLA-DR/imunologia , Antígenos de Histocompatibilidade Classe II/genética , Antígenos de Histocompatibilidade Classe II/imunologia , Humanos , Hidroximetilglutaril-CoA Redutases/metabolismo , Hidroximetilglutaril-CoA Redutases/farmacologia , Interferon gama/metabolismo , Interferon gama/farmacologia , Transplante de Órgãos , Serina-Treonina Quinases TOR/metabolismo , Transativadores/biossíntese , Transativadores/genética , Transativadores/farmacologia
4.
Cell Mol Biol (Noisy-le-grand) ; 64(10): 1-4, 2018 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-30084810

RESUMO

Preeclampsia is the major cause of both maternal and neonatal morbidity and mortality. Its insidence remains high and the management has not been established yet because its etiology and pathophysiological are still poorly understood. Theories regarding etiopathogenesis and management of preeclampsia have been postulated yet it remains controversial. Placental ischemic and angiogenic imbalance are suggested to be predisposing factors of preeclampsia. It is thereby targeted in prevention of preeclampsia. Unfortunately, both primary and secondary prevention using various supplements and drugs fails to exhibit good outcome. Overall, these efforts are considered useless. In recent years, researchers have been using statin derivative in management of preclampsia. It has been reported that statin provides protective effect in endothelial cells by inducing expression of Hmox-1 and inihibiting release of sFlt-1 as well as potent antioxidant properties. Thus, statin has been proposed as promising agent to significantly reduce anti-angiogenic in preeclamptic patients which is overviewed in this review based on recent studies.


Assuntos
Heme Oxigenase-1/genética , Hidroximetilglutaril-CoA Redutases/uso terapêutico , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Pré-Eclâmpsia/tratamento farmacológico , Regulação para Cima/efeitos dos fármacos , Animais , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Feminino , Heme Oxigenase-1/metabolismo , Humanos , Hidroximetilglutaril-CoA Redutases/farmacologia , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Pré-Eclâmpsia/genética , Pré-Eclâmpsia/metabolismo , Pré-Eclâmpsia/patologia , Gravidez , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/metabolismo
5.
Naunyn Schmiedebergs Arch Pharmacol ; 390(2): 215-223, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27913825

RESUMO

The aim of this study was to evaluate the effect of ß-caryophyllene on hypercholesterolemia using a model of hyperlipidemia induced by Triton WR-1339 in rats, as well as its possible effect on hepatic antioxidant enzymes. Thus, total cholesterol, triglycerides, low-density lipoprotein (LDL) cholesterol, and high-density lipoprotein (HDL) cholesterol were measured in serum, while reactive oxygen species (ROS), thiobarbituric acid reactive substances (TBARS), hepatic 3-hydroxy-3-methylglutayl coenzyme A (HMG-CoA) reductase, superoxide dismutase (SOD), and catalase (CAT) activities were measured in the hepatic tissue. In addition, seric concentrations of ß-caryophyllene were measured to perform correlation studies. Serum samples from hypercholesterolemic rats show higher (p < 0.05) levels of total cholesterol, triglycerides, and LDL cholesterol, and lower (p < 0.05) levels of HDL cholesterol compared to non-hypercholesterolemic rats. ß-Caryophyllene treatment reduced (p < 0.05) the levels of total cholesterol, triglycerides and LDL cholesterol, similar to the reference drug simvastatin. However, HDL cholesterol levels did not increase with the treatment. ß-Caryophyllene treatment was able to inhibit the HMG-CoA reductase activity, as well as to prevent the increase on ROS and TBARS levels, and ameliorate the antioxidant system. In summary, our findings demonstrated that ß-caryophyllene has hypolipidemic effect via inhibition of the hepatic HMG-CoA reductase, like the standard drug simvastatin, and this inhibition suggests a possible mechanism of hypolipidemic action. Thus, our results indicate that ß-caryophyllene can be used to treat dyslipidemic diseases because it exerts a similar effect as the reference drug, protecting the liver against lipid damage and improving the hepatic antioxidant defense system.


Assuntos
Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Hipercolesterolemia/tratamento farmacológico , Lipídeos/sangue , Fígado/efeitos dos fármacos , Sesquiterpenos/farmacologia , Animais , Antioxidantes/farmacologia , Biomarcadores/sangue , Catalase/metabolismo , Modelos Animais de Doenças , Feminino , Hidroximetilglutaril-CoA Redutases/farmacologia , Inibidores de Hidroximetilglutaril-CoA Redutases/sangue , Hipercolesterolemia/sangue , Hipercolesterolemia/induzido quimicamente , Fígado/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Sesquiterpenos Policíclicos , Polietilenoglicóis , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo , Sesquiterpenos/sangue , Sinvastatina/farmacologia , Superóxido Dismutase/metabolismo , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo
6.
Stat Med ; 33(10): 1621-45, 2014 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-24338893

RESUMO

Transform methods have proved effective for networks describing a progression of events. In semi-Markov networks, we calculated the transform of time to a terminating event from corresponding transforms of intermediate steps. Saddlepoint inversion then provided survival and hazard functions, which integrated, and fully utilised, the network data. However, the presence of censored data introduces significant difficulties for these methods. Many participants in controlled trials commonly remain event-free at study completion, a consequence of the limited period of follow-up specified in the trial design. Transforms are not estimable using nonparametric methods in states with survival truncated by end-of-study censoring. We propose the use of parametric models specifying residual survival to next event. As a simple approach to extrapolation with competing alternative states, we imposed a proportional incidence (constant relative hazard) assumption beyond the range of study data. No proportional hazards assumptions are necessary for inferences concerning time to endpoint; indeed, estimation of survival and hazard functions can proceed in a single study arm. We demonstrate feasibility and efficiency of transform inversion in a large randomised controlled trial of cholesterol-lowering therapy, the Long-Term Intervention with Pravastatin in Ischaemic Disease study. Transform inversion integrates information available in components of multistate models: estimates of transition probabilities and empirical survival distributions. As a by-product, it provides some ability to forecast survival and hazard functions forward, beyond the time horizon of available follow-up. Functionals of survival and hazard functions provide inference, which proves sharper than that of log-rank and related methods for survival comparisons ignoring intermediate events.


Assuntos
Modelos Estatísticos , Ensaios Clínicos Controlados Aleatórios como Assunto/métodos , Projetos de Pesquisa , Análise de Sobrevida , Humanos , Hidroximetilglutaril-CoA Redutases/administração & dosagem , Hidroximetilglutaril-CoA Redutases/farmacologia , Incidência , Cadeias de Markov , Isquemia Miocárdica/prevenção & controle , Pravastatina/administração & dosagem , Pravastatina/farmacologia
7.
Exp Cell Res ; 315(18): 3133-9, 2009 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-19500568

RESUMO

In this study, we show that sterol regulatory element binding proteins (SREBPs) regulate expression of Srd5a2, an enzyme that catalyzes the irreversible conversion of testosterone to dihydroxytestosterone in the male reproductive tract and is highly expressed in androgen-sensitive tissues such as the prostate and skin. We show that Srd5a2 is induced in livers and prostate from mice fed a chow diet supplemented with lovastatin plus ezitimibe (L/E), which increases the activity of nuclear SREBP-2. The three fold increase in Srd5a2 mRNA mediated by L/E treatment was accompanied by the induction of SREBP-2 binding to the Srd5a2 promoter detected by a ChIP-chip assay in liver. We identified a SREBP-2 responsive region within the first 300 upstream bases of the mouse Srd5a2 promoter by co-transfection assays which contain a site that bound SREBP-2 in vitro by an EMSA. Srd5a2 protein was also induced in cells over-expressing SREBP-2 in culture. The induction of Srd5a2 through SREBP-2 provides a mechanistic explanation for why even though statin therapy is effective in reducing cholesterol levels in treating hypercholesterolemia it does not compromise androgen production in clinical studies.


Assuntos
3-Oxo-5-alfa-Esteroide 4-Desidrogenase/genética , Regulação Enzimológica da Expressão Gênica , Hidroximetilglutaril-CoA Redutases/farmacologia , Fígado/enzimologia , Próstata/enzimologia , Proteína de Ligação a Elemento Regulador de Esterol 2/metabolismo , 3-Oxo-5-alfa-Esteroide 4-Desidrogenase/metabolismo , Animais , Atorvastatina , Azetidinas/farmacologia , Azetidinas/uso terapêutico , Linhagem Celular Tumoral , Ezetimiba , Ácidos Heptanoicos/farmacologia , Ácidos Heptanoicos/uso terapêutico , Hidroximetilglutaril-CoA Redutases/uso terapêutico , Hipercolesterolemia/tratamento farmacológico , Fígado/efeitos dos fármacos , Lovastatina/farmacologia , Lovastatina/uso terapêutico , Masculino , Camundongos , Regiões Promotoras Genéticas , Próstata/efeitos dos fármacos , Neoplasias da Próstata/enzimologia , Pirróis/farmacologia , Pirróis/uso terapêutico , Proteína de Ligação a Elemento Regulador de Esterol 2/agonistas , Transfecção
9.
Biomaterials ; 29(17): 2656-62, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18377983

RESUMO

Ferumoxtran-10 is an ultrasmall superparamagnetic iron oxide nanoparticle potentially useful as a contrast material in magnetic resonance imaging for the diagnosis of inflammatory and degenerative disorders associated with high macrophage activity. In clinical trials, it is currently applied to monitor the effect of atorvastatin therapy on macrophage activity in human carotid plaques. A recent study reported the inhibition of iron oxide nanoparticle uptake in macrophages by lovastatin, an effect which could compromise the suitability of Ferumoxtran-10 as an MRI contrast material in patients on statin therapy. Therefore, we examined the effect of atorvastatin on human monocyte-macrophage uptake of Ferumoxtran-10 in vitro using biochemical assays, magnetic resonance imaging and transmission electron microscopy. Our study showed that non-toxic concentrations of atorvastatin did not affect the amount of Ferumoxtran-10 taken up by HMMs. Furthermore, the intracellular distribution of iron oxide nanoparticles and the resulting MRI signal intensities remained unchanged by statin treatment. These results were obtained using atorvastatin concentrations probably vastly exceeding those reached in patient plasma in vivo. Atorvastatin therapy itself is therefore unlikely to affect Ferumoxtran-10 based macrophage detection by MRI, a prerequisite for the use of this contrast material to monitor lesion macrophage burden during lipid-lowering therapy.


Assuntos
Ácidos Heptanoicos/farmacologia , Ferro/farmacocinética , Macrófagos/efeitos dos fármacos , Imageamento por Ressonância Magnética/métodos , Nanopartículas/química , Óxidos/farmacocinética , Pirróis/farmacologia , Atorvastatina , Células Cultivadas , Meios de Contraste/farmacocinética , Dextranos , Relação Dose-Resposta a Droga , Óxido Ferroso-Férrico , Humanos , Hidroximetilglutaril-CoA Redutases/farmacologia , Macrófagos/metabolismo , Macrófagos/ultraestrutura , Nanopartículas de Magnetita , Tamanho da Partícula , Acetato de Tetradecanoilforbol/farmacologia
10.
Atherosclerosis ; 197(2): 588-95, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17904146

RESUMO

OBJECTIVES: To evaluate the relationship between CD40/CD40L system and increased thrombogenesis in AF, and to test the effects of simvastatin treatment. METHODS: In vitro study using human tissue, University Hospital (tertiary referral center). Experiments on right atrial segments obtained before the onset of cardiopulmonary bypass were done in either presence or absence of 5 microM simvastatin. Two groups of patients in either chronic atrial fibrillation or sinus rhythm at the time of cardiac surgery. The endocardial expression of CD40, the release of CD40L, and adhesion of platelets to endocardium. Additionally, the thickness of platelet aggregates and the platelet distribution on the endocardium were also evaluated. RESULTS: Atrial fibrillation was associated with a significant increase of endocardial CD40 expression (293.1+/-55.1 pg/ml vs. 230.9+/-53.3 pg/ml, p<0.01), and platelet-endocardial adhesion compared with sinus rhythm atria (10.8+/-2.2 vs. 5.2+/-1.3 platelet CD41 AU p<0.01). At immunofluorescence about 62% of fibrillating endocardium was covered by platelets, compared with 12% of not sinus rhythm atria. Addition of simvastatin significantly reduced CD40 expression as well as platelet adhesion to fibrillating atria; its efficacy was not reversed by the addition of mevalonic acid. CONCLUSIONS: Chronic atrial fibrillation acutely upregulates CD40 expression as well as platelet adhesion to the endocardium. Simvastatin is effective in modulating this expression, thus it may potentially contribute to reduce the risk of intra-atrial thrombus formation.


Assuntos
Fibrilação Atrial/fisiopatologia , Antígenos CD40/metabolismo , Endocárdio/efeitos dos fármacos , Hidroximetilglutaril-CoA Redutases/farmacologia , Adesividade Plaquetária/efeitos dos fármacos , Sinvastatina/farmacologia , Idoso , Fibrilação Atrial/metabolismo , Função do Átrio Direito , Antígenos CD40/efeitos dos fármacos , Ligante de CD40/metabolismo , Estudos de Casos e Controles , Endocárdio/fisiopatologia , Feminino , Átrios do Coração/fisiopatologia , Humanos , Técnicas In Vitro , Masculino , Pessoa de Meia-Idade
11.
Atherosclerosis ; 181(1): 87-92, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15939058

RESUMO

Inhibitors of 3-hydroxy-3-methylglutaryl CoA (HMG-CoA) reductase are antilipidemic agents (statins) widely used for the prevention of cardiovascular diseases. Recent studies have suggested that the overall benefits of statin therapy cannot be accounted for solely by its antilipidemic effect. To obtain further insight into the mechanism of action of statins, we studied the effect of pitavastatin on the generation of reactive oxygen species (ROS) by peritoneal polymorphonuclear leukocytes (PMN) obtained from control and hyperlipidemic guinea pigs. Flow cytometric analysis revealed that the amount of ROS generated by PMN from the hyperlipidemic animals that had been administered a laurate-containing diet (LD) for 4 weeks was larger than that from the normal diet (ND) group (837% increase, ND; 82.17 arbitrary units, LD; 688.10 arbitrary units, P < 0.01, n = 6). Administration of pitavastatin to the LD group significantly decreased plasma levels of total cholesterol (TC) and low-density lipoprotein (LDL) with a reduction in ROS generation by PMN (19% decrease, LD control; 688.10 arbitrary units, LD + pitavastatin; 556.87 arbitrary units, P < 0.01, n = 6). Western blotting analysis revealed that the expression of protein kinase C alpha (PKC alpha) and betaI was higher in PMN from the LD group than in PMN from the ND group (PKC alpha; 74% increase, PKC betaI; 339% increase, P < 0.05, n = 4, respectively). Furthermore, expression of NADPH oxidase gp91phox in PMN from the LD group was higher than that in PMN from the ND group (18% increase, P < 0.05, n = 4). By administration of pitavastatin to the LD group, the expression of PKC alpha, betaI and gp91phox was suppressed compared with the control LD group (PKC alpha; 41% decrease, PKC beta; 28% decrease, gp91phox; 56% decrease, P < 0.05, n = 4, respectively). These results indicate that PMN from hyperlipidemic animals is associated with an accelerated respiratory burst of ROS by increasing the expression of PKC alpha, betaI and gp91phox, and pitavastatin inhibits this by suppressing the expression of those proteins.


Assuntos
Hiperlipidemias/metabolismo , Neutrófilos/metabolismo , Estresse Oxidativo , Animais , Western Blotting , Inibidores Enzimáticos/farmacologia , Cobaias , Hidroximetilglutaril-CoA Redutases/farmacologia , Hiperlipidemias/patologia , Lipídeos/sangue , Masculino , NADPH Oxidases/antagonistas & inibidores , Neutrófilos/enzimologia , Cavidade Peritoneal/patologia , Proteína Quinase C/antagonistas & inibidores , Quinolinas/farmacologia , Espécies Reativas de Oxigênio/metabolismo
12.
BMC Cardiovasc Disord ; 4: 4, 2004 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-15125784

RESUMO

BACKGROUND: Statins are cholesterol-lowering drugs that are widely used to reduce the risk of cardiac infarction. Their beneficial clinical effects, however, are not restricted to their influence on cholesterol production. As several studies have shown that they have a potency of relaxing blood vessels. METHODS: We measured the effects of statins on the intracellular free calcium concentration ([Ca2+]i) in human umbilical vein endothelial cells (HUVEC) after acute application and 24-h-preincubation of statins. RESULTS: Incubation of the cells for 24 h with cerivastatin or fluvastatin significantly increased the resting [Ca2+]i. For cerivastatin this effect manifested at a concentration of 1 microM. Increase of resting [Ca2+]i in the presence of cerivastatin also occurred when the nitric oxide synthase was inhibited. Transient Ca2+ release induced by histamine was not affected. CONCLUSIONS: The increase of resting [Ca2+]i after incubation with cerivastatin or fluvastatin may provide an explanation for the direct effects of statins on the endothelial-dependent vasodilatation and restoration of endothelial activity in vivo.


Assuntos
Anticolesterolemiantes/farmacologia , Cálcio/metabolismo , Endotélio Vascular/efeitos dos fármacos , Hidroximetilglutaril-CoA Redutases/farmacologia , Endotélio Vascular/metabolismo , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Ácidos Graxos Monoinsaturados/farmacologia , Fluvastatina , Humanos , Indóis/farmacologia , Piridinas/farmacologia , Veias Umbilicais/efeitos dos fármacos , Vasodilatação
13.
Yakugaku Zasshi ; 124(3): 159-63, 2004 Mar.
Artigo em Japonês | MEDLINE | ID: mdl-15049134

RESUMO

Proliferation of vascular smooth muscle cells (VSMC) stimulated by oxidative stresses and reactive oxygen species (ROS) may play a pivotal role in the pathogenesis of atherosclerosis. Antiatherosclerotic effects of angiotensin II receptor blockers, angiotensin converting enzyme inhibitors, HMG CoA reductase inhibitors, calcium channel blocker and epalrestat were studied with an in vitro guinea-pig basilar artery smooth muscle cell (GBa-SM3) culture system over 3 days incubated with 0 to 10% of fetal bovine serum. Results demonstrated that simvastatin (0.1 mM), fluvastatin (0.3 mM), amlodipine (0.2 mM) and epalrestat (1 mM) elicited significant (p < 0.05 or 0.01) antiproliferative effects, whereas losartan (1 mM), valsartan (1 mM), enalapril (0.1 mM), captopril (1 mM), trandolapril (0.01 mM), pravastatin (0.7 mM) did not. In conclusion, the present in vitro VSMC culture system may serve as a comprehensive screening method for pleiotropic effects of commonly used therapeutic agents.


Assuntos
Anlodipino/farmacologia , Antagonistas de Receptores de Angiotensina , Inibidores da Enzima Conversora de Angiotensina/farmacologia , Artéria Basilar , Bloqueadores dos Canais de Cálcio/farmacologia , Divisão Celular/efeitos dos fármacos , Ácidos Graxos Monoinsaturados/farmacologia , Hidroximetilglutaril-CoA Redutases/farmacologia , Indóis/farmacologia , Músculo Liso Vascular/citologia , Rodanina/análogos & derivados , Rodanina/farmacologia , Sinvastatina/farmacologia , Animais , Arteriosclerose/etiologia , Arteriosclerose/prevenção & controle , Células Cultivadas , Depressão Química , Fluvastatina , Cobaias , Estresse Oxidativo , Espécies Reativas de Oxigênio , Tiazolidinas
14.
BMC Cardiovasc Disord ; 3: 6, 2003 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-12871602

RESUMO

BACKGROUND: Statins effectively lower blood cholesterol and the risk of cardiovascular death. Immunomodulatory actions, independent of their lipid-lowering effect, have also been ascribed to these compounds. Since macrophages participate in several vascular pathologies, we examined the effect of statin treatment on the survival and differentiation of primary human monocytes. METHODS: Peripheral blood mononuclear cells (PBMCs) from healthy individuals were cultured in the presence or absence of mevastatin. Apoptosis was monitored by annexin V / PI staining and flow cytometry. In parallel experiments, cultures were stimulated with LPS in the presence or absence of mevastatin and the release of IL-1beta and IL-1Ra was measured by ELISA. RESULTS: Among PBMCs, mevastatin-treated monocytes were particularly susceptible to apoptosis, which occurred at doses >1 microM and was already maximal at 5 microM. However, even at the highest mevastatin dose used (10 microM), apoptosis occurred only after 24 h of culture, possibly reflecting a requirement for cell commitment to differentiation. After 72 h of treatment the vast majority (>50%) of monocytes were undergoing apoptosis. Stimulation with LPS revealed that mevastatin-treated monocytes retained the high IL-1beta output characteristic of undifferentiated cells; conversely, IL-1Ra release was inhibited. Concurrent treatment with mevalonolactone prevented the induction of apoptosis and suppressed both IL-1beta and IL-1Ra release in response to LPS, suggesting a rate-limiting role for HMG-CoA reductase in monocyte differentiation. CONCLUSIONS: Our findings indicate that statins arrest the functional differentiation of monocytes into macrophages and steer these cells into apoptosis, suggesting a novel mechanism for the vasculoprotective properties of HMG-CoA reductase inhibitors.


Assuntos
Apoptose/fisiologia , Hidroximetilglutaril-CoA Redutases/farmacologia , Interleucina-1/metabolismo , Lovastatina/análogos & derivados , Lovastatina/farmacologia , Monócitos/efeitos dos fármacos , Sialoglicoproteínas/metabolismo , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/fisiologia , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Humanos , Proteína Antagonista do Receptor de Interleucina 1 , Lipopolissacarídeos/farmacologia , Macrófagos/fisiologia , Monócitos/fisiologia , Fatores de Tempo
15.
Curr Med Chem ; 9(20): 1831-50, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12369881

RESUMO

Statins significantly reduce cardiovascular-related morbidity and mortality in patients with and without coronary artery disease. The potential of this drug class has yet to be fully explored. Accumulating evidence from basic research and clinical trials indicates that statins have pleiotropic effects that may largely account for the clinical benefits observed. Potential beneficial effects of these agents include enhancement of nitric oxide production in vasculature and the kidney. Statins have been shown to stabilize unstable plaques, improve vascular relaxation, and promote new vessel formation. Clinical trials and animal studies have shown that these agents reduce cardiovascular disease (CVD) risks and events, progression of nephropathy, development of diabetes, and fracture rates; these are benefits that go beyond lipid lowering alone. Potential beneficial effects are due to the positive impact on vascular and glomerular nitric oxide (NO) production and attenuation of vascular inflammation. Effects on bone, including fracture reduction, are thought to be mediated by direct action on bone formation. Moreover, potential reduction in the development of diabetes as observed in the West of Scotland Coronary Prevention Study (WOSCOPS) may relate to the improvement in insulin sensitivity. These actions are mediated, in part, by the effects on small G-proteins, modulation of signaling cascades, transcription, and gene expression. In particular, the inhibition of small GTP-binding proteins, Rho, Ras, and Rac, whose proper membrane localization and function are dependent on isoprenylation, may play an important role in mediating the direct cellular effects of statins on the vascular wall. The clinical relevance of these effects is beginning to be recognized, and ongoing studies will be able to answer these many questions in the near future. Actions of statins on vascular, glomerular, bone, and insulin-sensitive tissue as well as effects of statins on cognitive function and oncoprotection will be discussed in this review.


Assuntos
Anticolesterolemiantes/farmacologia , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Metabolismo dos Lipídeos , Anticolesterolemiantes/uso terapêutico , Doença da Artéria Coronariana/tratamento farmacológico , Doença da Artéria Coronariana/metabolismo , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/metabolismo , Humanos , Hidroximetilglutaril-CoA Redutases/farmacologia , Hidroximetilglutaril-CoA Redutases/uso terapêutico
16.
Bull Mem Acad R Med Belg ; 157(10-12): 427-31; discussion 431-4, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12854183

RESUMO

High LDL-cholesterol is a risk factor for atherosclerosis and cardiovascular events. Dysfunction of the endothelium, e.g. the impairment of its capacity to produce nitric oxide (NO) is an early step in atherogenesis. We identified a mechanism of endothelial toxicity of LDL-cholesterol that alters the activity of the endothelial isoform of nitric oxide synthase (eNOS) in the absence of changes in its expression (abundance). This effect involves the transcriptional activation of the gene encoding caveolin-1, a structural protein of caveolae that acts as a negative allosteric regulator of eNOS. The effect is proportional to the increase in intracellular cholesterol that modulates caveolin-1 gene transcription, through the Sterol Regulatory Element Binding Protein (SREBP). Treatment of endothelial cells with statins (inhibitors of cholesterol synthesis) abrogates caveolin-1 upregulation and restores eNOS activity in vitro and in vivo in genetically apoE-deficient, hypercholesterolemic mice.


Assuntos
LDL-Colesterol/fisiologia , Endotélio Vascular/fisiopatologia , Hidroximetilglutaril-CoA Redutases/farmacologia , Animais , Humanos , Hidroximetilglutaril-CoA Redutases/uso terapêutico , Óxido Nítrico/fisiologia , Fatores de Risco , Transdução de Sinais
17.
Am Heart J ; 141(3): 342-7, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11231429

RESUMO

BACKGROUND: As a class, statins are remarkably effective in reducing low-density lipoprotein (LDL) cholesterol, and several of these drugs have now been shown to reduce coronary heart disease morbidity and mortality. However, several important controversies in the use of statins remain to be answered by clinical trials. For example, it is controversial whether marked cholesterol reduction to levels below 100 mg/dL would further reduce the incidence of coronary heart disease. Furthermore, concerns about differences among statins for nonlipid effects has raised the concern that the assumption of a class effect is premature until head-to-head clinical trials are completed. METHODS: Arterial Biology for the Investigation for the Treatment Effects of Reducing Cholesterol (ARBITER) is a single-center, randomized, active-controlled study comparing the efficacy of high-dose atorvastatin (80 mg/d) and pravastatin (40 mg/d) in patients being treated for either the primary or secondary prevention of coronary heart disease. This trial will enroll up to 200 patients for the primary end point of the mean change in intima-media thickness of the common carotid artery. This effect will be evaluated over a treatment duration of 12 months. Secondary end points include the effects of statin therapy on inflammatory and hemostatic markers (C-reactive protein and fibrinogen). CONCLUSION: ARBITER will provide important data on the role of marked LDL reduction and the "class effect" theory of statin therapy in cardiovascular medicine.


Assuntos
Artéria Carótida Primitiva/patologia , Doença das Coronárias/patologia , Ácidos Heptanoicos/farmacologia , Hidroximetilglutaril-CoA Redutases/farmacologia , Pravastatina/farmacologia , Pirróis/farmacologia , Túnica Íntima/patologia , Túnica Média/patologia , Atorvastatina , Artéria Carótida Primitiva/efeitos dos fármacos , LDL-Colesterol/análise , Doença das Coronárias/tratamento farmacológico , Ácidos Heptanoicos/uso terapêutico , Humanos , Hidroximetilglutaril-CoA Redutases/uso terapêutico , Pravastatina/uso terapêutico , Pirróis/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto , Projetos de Pesquisa , Túnica Íntima/efeitos dos fármacos , Túnica Média/efeitos dos fármacos
18.
Circulation ; 97(10): 946-52, 1998 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-9529261

RESUMO

BACKGROUND: We determined the effect of incorporating the results of eight recently published trials of Hmg CoA reductase inhibitors ("statins") on the conclusions from our previously published meta-analysis regarding the clinical benefit of cholesterol lowering. METHODS AND RESULTS: We used the same analytic approach as in our previous investigation, separating the specific effects of cholesterol lowering from the effects attributable to the different types of intervention studied. The reductions in coronary heart disease (CHD) and total mortality risk observed for the statins fell near the predictions from our earlier meta-analysis. Including the statin trial findings into the calculations led to a prediction that for every 10 percentage points of cholesterol lowering, CHD mortality risk would be reduced by 15% (P<.001), and total mortality risk would be reduced by 11% (P<.001), as opposed to the values of 13% and 10%, respectively, reported previously. Cholesterol lowering in general and by the statins in particular does not increase non-CHD mortality risk. CONCLUSIONS: Adding the results from the statin trials confirmed our original conclusion that lowering cholesterol is clinically beneficial. The relationships (slope) between cholesterol lowering and reduction in CHD and total mortality risk became stronger, and the standard error of the estimated slopes decreased by about half. Use of statins does not increase non-CHD mortality risk. The effect of the statins on CHD and total mortality risk can be explained by their lipid-lowering ability and appears to be directly proportional to the degree to which they lower lipids.


Assuntos
Colesterol/sangue , Doença das Coronárias/sangue , Doença das Coronárias/prevenção & controle , Hidroximetilglutaril-CoA Redutases/uso terapêutico , Ensaios Clínicos como Assunto , Doença das Coronárias/mortalidade , Doença das Coronárias/fisiopatologia , Humanos , Hidroximetilglutaril-CoA Redutases/farmacologia
19.
Br J Clin Pharmacol ; 41(5): 381-7, 1996 May.
Artigo em Inglês | MEDLINE | ID: mdl-8735678

RESUMO

1. We have examined the interaction between aerobic exercise and lipid-lowering drugs in a crossover study of 16 healthy normolipidaemic volunteers who each received 21 days' treatment with bezafibrate (400 mg), fluvastatin (40 mg), and placebo, in random order. 2. Fluvastatin treatment reduced pre-exercise total cholesterol (TC) by 23% (P < 0.0001), low-density lipoprotein cholesterol (LDL-C) by 33% (P < 0.0001), and plasma triglycerides by 11%, compared with pre-treatment values. Bezafibrate reduced TC by 11% (P < 0.01); LDL-C by 9%; and plasma triglycerides by 40% (P < 0.01), compared with pre-treatment values. 3. During exercise, in comparison with placebo, and fluvastatin treatment, respectively, bezafibrate significantly reduced mean fat oxidation: 31% vs 39%, P = 0.035, 31% vs 39%, P = 0.002, plasma free fatty acid (FFA) availability, e.g. after 90 min of exercise: (t90) 520 vs 662 mumol 1(-1), P = 0.054, 520 vs 725 mumol 1(-1), P = 0.016, and plasma levels of glycerol (t90): 59 vs 74 mumol 1(-1), P = 0.037, 59 vs 73 mumol 1(-1), P = 0.016. Fluvastatin had no impact on fat metabolism in comparison with placebo. 4. Reduced plasma FFA concentration and lower fat oxidation during prolonged exercise on bezafibrate treatment may be due to an inhibition of hepatic acetyl coenzyme A carboxylase, resulting in reduced FFA release from adipose tissue. 5. The possibility that impaired fat metabolism on fibrates could induce premature fatigue during exercise of moderate duration and intensity should be examined in hyperlipidaemic patients.


Assuntos
Bezafibrato/farmacologia , Exercício Físico/fisiologia , Ácidos Graxos Monoinsaturados/farmacologia , Ácidos Graxos não Esterificados/metabolismo , Hidroximetilglutaril-CoA Redutases/farmacologia , Hipolipemiantes/farmacologia , Indóis/farmacologia , Adulto , Análise de Variância , Bezafibrato/sangue , Estudos Cross-Over , Método Duplo-Cego , Metabolismo Energético/efeitos dos fármacos , Ácidos Graxos Monoinsaturados/sangue , Feminino , Fluvastatina , Humanos , Hidroximetilglutaril-CoA Redutases/sangue , Inibidores de Hidroximetilglutaril-CoA Redutases , Hipolipemiantes/sangue , Indóis/sangue , Masculino , Oxirredução
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