普伐他汀和洛沙坦联合应用对慢性环孢素A肾毒性模型大鼠转化生长因子诱导基因h3的抑制作用

Inhibitory effects of pravastatin and losartan on the expression of transforming growth factor inducible gene h3 in rats model of chroniccyclosporine A nephrotoxicity

[目的]探讨普伐他汀和洛沙坦联合应用对慢性环孢素A(CsA)肾毒性模型大鼠抗纤维化作用的分子机制.[方法]取Sprague-Dawley雄性大鼠随机分为对照组(橄榄油1mg/kg)、CsA毒性组(皮下注射CsA 15mg/kg)、洛沙坦治疗组(洛沙坦10mg/kg+CsA)、普伐他汀治疗组(普伐他汀20mg/kg+CsA)、联合治疗组(CsA+洛沙坦+普伐他汀),均每日给药1次,持续4周.检测各组大鼠肾功能、收缩期血压、血脂水平;利用三色染色观察肾组织纤维化程度;利用Northern杂交、RNA原位杂交、免疫印迹法分别检测转化生长因子β1(TGF-β1)和TGF-β诱导基因h3(βig-h3)的表达.[结果]与CsA毒性组比较,普伐他汀和洛沙坦单独治疗组肾小管间质纤维化明显减轻(洛沙坦24.1%±4.0%,普伐他汀30.3%±5.2%,P<0.01,2.0%±3.0%),同时TGF-β1(洛沙坦230%±20%,普伐他汀240%±15%,P<0.01)和βig-h3(洛沙坦178%±21%,普伐他汀167%±10%,P<0.01)表达均明显降低,联合治疗进一步降低上述指标水平(肾小管间质纤维化程度13.5%±2.5%,TGF-β1 150%±28%,βig-h3 126%±9%,P<0.01).直线相关分析结果显示,βig-h3表达与TGF-β1(r=0.787,P<0.001)和肾小管间质纤维化程度(r=0.688,P<0.001)呈正相关.但是各组收缩期血压和血脂水平间差异均无统计学意义(P>0.05).[结论]在慢性CsA肾毒性中,普伐他汀和洛沙坦联合应用通过抑制βig-h3表达起到抗纤维化协同作用,而不依赖于降低血压或降低血脂作用.

OBJECTIVE To explore the anti-fibrosis mechanism of combined application of pravastatin and losartan in rats model of chroniccyclosporine A（CsA） nephrotoxicity. METHODS Male Sprague Dawley rats were randomly divided into control group（olive oil 1 mg/kg）, CsA group（CsA 15 mg/kg）, losartan group （CsA 15 mg/kg and losartan 10 mg/kg）, pravastatin group（CsA 15 mg/kg and pravastatin 20 mg/kg） and combined application group（CsA 15 mg/kg, losartan 10 mg/kg and pravastatin 20 mg/kg）, and they were administrated of drugs by 1 time per day for 4 weeks. Renal function,systolicblood pressure and blood lipid level were measured.Masson trichrome staining was used to observed the tubular interstitial fibrosis （TIF）, and the expressions of transforming growth factor β1 （TGF-β1） and TGF-β inducible gene-h3 （βig-h3） were detected by Northern blot, in situ hybridization and western blotting. RESULTS Compared with the CsA group, the pravastatin and losartan group showed a significant decrease of TIF （losartan.24. 1% ± 4.0 % ; pravastatin.30.3 % ± 5.2 %, P〈 0.01 vs. 42.0% ± 3.0%） and had a statistically significant decrease in the expression of TGF-β1 （losartan. 230% ± 20% ; pravastatin. 240% ± 15%, P 〈 0.01） and βig-h3 （losartan. 178% ± 21% pravastatin： 167% ± 10%, P 〈 0.01）. Combined application group showed a further decrease of these parameters compared with other groups （TIF.13.5 % P%0. 01）. Linear correlation analysis revealed that ± 2.5% ;TGF-β1：150% ± 28% ;βig-h3.126% ± 9%, βig-h3 expression positively associated with TGF-~I expression （r = 0. 787, P〈0. 001） and TIF （r = 0. 688, P〈0. 001）. There were no significant differences in systolic blood pressure and serum lipid level between each group. CONCLUSION Combined application of pravastatin and losartan played a synergistic effect on anti-fibrosis by inhibiting βig-h3 expression in a model of chronic CsA nephrotoxicity, and this effect was independent of their lowing blood pressure and lipid level mechanism.