ABSTRACT
<p><b>OBJECTIVE</b>To investigate the effect and potential mechanisms of rutaecarpine (Rut) in a rat artery balloon-injury model.</p><p><b>METHODS</b>The intimal hyperplasia model was established by rubbing the endothelia with a balloon catheter in the common carotid artery (CCA) of rats. Fifty rats were randomly divided into five groups, ie. sham, model, Rut (25, 50 and 75 mg/kg) with 10 rats of each group. The rats were treated with or without Rut (25, 50, 75 mg/kg) by intragastric administration for 14 consecutive days following injury. The morphological changes of the intima were evaluated by hematoxylin-eosin staining. The expressions of proliferating cell nuclear antigen (PCNA) and smooth muscle (SM) α-actin in the ateries were assayed by immunohistochemical staining. The mRNA expressions of c-myc, extracellular signal-regulated kinase 2 (ERK2), MAPK phosphatase-1 (MKP-1) and endothelial nitric oxide synthase (eNOS) were determined by real-time reverse transcription-polymerase chain reaction. The protein expressions of MKP-1 and phosphorylated ERK2 (p-ERK2) were examined by Western blotting. The plasma contents of nitric oxide (NO) and cyclic guanosine 3',5'-monophosphate (cGMP) were also determined.</p><p><b>RESULTS</b>Compared with the model group, Rut treatment significantly decreased intimal thickening and ameliorated endothelial injury (P<0.05 or P<0.01). The positive expression rate of PCNA was decreased, while the expression rate of SM α-actin obviously increased in the vascular wall after Rut (50 and 75 mg/kg) administration (P<0.05 or P<0.01). Furthermore, the mRNA expressions of c-myc, ERK2 and PCNA were downregulated while the expressions of eNOS and MKP-1 were upregulated (P<0.05 or P<0.01). The protein expressions of MKP-1 and the phosphorylation of ERK2 were upregulated and downregulated after Rut (50 and 75 mg/kg) administration (P<0.05 or P<0.01), respectively. In addition, Rut dramatically reversed balloon injury-induced decrease of NO and cGMP in the plasma (P<0.05 or P<0.01).</p><p><b>CONCLUSION</b>Rut could inhibit the balloon injury-induced carotid intimal hyperplasia in rats, possibly mediated by promotion of NO production and inhibiting ERK2 signal transduction pathways.</p>
Subject(s)
Animals , Male , Actins , Metabolism , Carotid Arteries , Metabolism , Pathology , Carotid Artery Injuries , Drug Therapy , Genetics , Pathology , Cyclic GMP , Blood , Disease Models, Animal , Gene Expression Regulation , Hyperplasia , Indole Alkaloids , Pharmacology , Therapeutic Uses , Nitric Oxide , Blood , Phosphorylation , Proliferating Cell Nuclear Antigen , Metabolism , Quinazolines , Pharmacology , Therapeutic Uses , RNA, Messenger , Genetics , Metabolism , Rats, Sprague-Dawley , Tunica Intima , PathologyABSTRACT
<p><b>OBJECTIVE</b>To investigate the effects of evodiamine (Evo), a component of Evodiaminedia rutaecarpa (Juss.) Benth, on cardiomyocyte hypertrophy induced by angiotensin II (Ang II) and further explore the potential mechanisms.</p><p><b>METHODS</b>Cardiomyocytes from neonatal Sprague Dawley rats were isolated and characterized, and then the cadiomyocyte cultures were randomly divided into control, model (Ang II 0.1 μmol/L), and Evo (0.03, 0.3, 3 μmol/L) groups. The cardiomyocyte surface area, protein level, intracellular free calcium ([Ca]) concentration, activity of nitric oxide synthase (NOS) and content of nitric oxide (NO) were measured, respectively. The mRNA expressions of atrial natriuretic factor (ANF), calcineurin (CaN), extracellular signal-regulated kinase-2 (ERK-2), and endothelial nitric oxide synthase (eNOS) of cardiomyocytes were analyzed by real-time reverse transcriptionpolymerase chain reaction. The protein expressions of calcineurin catalytic subunit (CnA) and mitogen-activated protein kinase phosphatase-1 (MKP-1) were detected by Western blot analysis.</p><p><b>RESULTS</b>Compared with the control group, Ang II induced cardiomyocytes hypertrophy, as evidenced by increased cardiomyocyte surface area, protein content, and ANF mRNA expression; increased intracellular free calcium ([Ca]) concentration and expressions of CaN mRNA, CnA protein, and ERK-2 mRNA, but decreased MKP-1 protein expression (P<0.05 or P<0.01). Compared with Ang II, Evo (0.3, 3 μmol/L) significantly attenuated Ang II-induced cardiomyocyte hypertrophy, decreased the [Ca] concentration and expressions of CaN mRNA, CnA protein, and ERK-2 mRNA, but increased MKP-1 protein expression (P<0.05 or P<0.01). Most interestingly, Evo increased the NOS activity and NO production, and upregulated the eNOS mRNA expression (P<0.05).</p><p><b>CONCLUSION</b>Evo signifificantly attenuated Ang II-induced cardiomyocyte hypertrophy, and this effect was partly due to promotion of NO production, reduction of [Ca]i concentration, and inhibition of CaN and ERK-2 signal transduction pathways.</p>
Subject(s)
Animals , Angiotensin II , Atrial Natriuretic Factor , Metabolism , Calcineurin , Genetics , Metabolism , Calcium , Metabolism , Dual Specificity Phosphatase 1 , Genetics , Metabolism , Extracellular Signal-Regulated MAP Kinases , Genetics , Metabolism , Hypertrophy , Myocytes, Cardiac , Metabolism , Pathology , Nitric Oxide , Metabolism , Nitric Oxide Synthase Type III , Metabolism , Quinazolines , Pharmacology , RNA, Messenger , Genetics , Metabolism , Rats, Sprague-DawleyABSTRACT
OBJECTIVE: To examine the inhibitory effects of evodiamine on vascular neointimal hyperplasia in balloon-injured carotid artery of rats and explore the possible mechanisms. METHODS: Healthy male Sprague Dawley rat vascular neointimal hyperplasia model was made by rubbing the endothelia of common carotid artery with a balloon, and then the rats were randomly divided into sham operation control group, model control group, evodiamine low(40 mg · kg-1) and high(80 mg· kg-1) dose groups. Evodiamine was intragastric administration for 14 consecutive days, and the sham operation or control rats were given with distilled water. After consecutive 14 d, the neointimal hyperplasia degree was observed by histopathological alterations and by calculating the proliferating cell nuclear antigen(PCNA) positive cells expression percentage in the common carotid arter-y. The levels of nitric oxide (NO) and cyclic guanosine monophosphate (cGMP) in plasma of rats were measured respectively. The mRNA expressions of PCNA, endothelial nitric oxide synthase(eNOS) and SM α-actin in carotid artery wall were analyzed separately by real time RT-PCR. RESULTS: The neointimal hyperplasia was very serious, as evidenced by thickened neointima and narrowed lumen in carotid artery balloon-injured rats (model control group). Compared with the model control group, evodiamine 40 and 80 mg · kg-1 administration could significantly ameliorate the histopathology of common carotid artery, decrease the positive expression rate of PCNA, but increase the levels of NO, cGMP in plasma of rats, downregulate the PCNA mRNA expression and upregulate mRNA expressions of eNOS and SM α-actin, respectively. CONCLUSION: Evodiamine can depress the vascular neointimal hyperplasia induced by artery endothelia rubbing in rats, the mechanism may be related, at least partly, to the promotion of NO production.