芝麻素联用维生素E对化学性肾损伤大鼠eNOS/iNOS表达的影响

Effects of sesamin combined with vitamin E on the expression of eNOS/iNOS in chemically-induced renal injury rats

目的:探讨芝麻素(Ses)和维生素E(VE)联用对化学性肾损伤大鼠的保护作用及其对内皮型一氧化氮合酶(eNOS)/诱导型一氧化氮合酶(iNOS)表达的影响。方法:SD大鼠28只给予D-半乳糖(D-gal,180mg·kg-1·d-1,i.p.)和三氯化铝(AlCl3,15mg·kg-1·d-1,i.g.)20周建立化学性肾损伤模型。于造模第13周将大鼠随机分成模型组(生理盐水,NS,5.0mL·kg-1·d-1)、Ses组(160mg·kg-1·d-1)、维生素E组(VE,10mg·kg-1·d-1)及Ses+VE组(160mg·kg-1·d-1+10mg·kg-1·d-1),按设定剂量分别灌胃给药8周,另设正常对照组(生理盐水,NS,5.0mL·kg-1·d-1,i.g.)。末次给药后称体质量(BW)和肾湿重(HWW);化学比色法测肾组织一氧化氮(NO)、总抗氧化能力(T-AOC)、超氧化物歧化酶(SOD)和丙二醛(MDA)含量;HE和Masson染色分别观察肾脏病理组织学和胶原纤维变化;免疫组化法测iNOS阳性细胞表达;Western Blot测eNOS蛋白表达。结果:与模型组相比,Ses、VE和Ses+VE组能明显减轻肾脏病理组织损伤和胶原纤维沉积;降低肾匀浆NO、MDA含量,提高T-AOC、SOD活性;上调肾脏eNOS蛋白表达,下调iNOS蛋白表达,且疗效Ses+VE组优于单用Ses、VE组(P<0.05,P<0.01)。结论:Ses联用VE对抗化学性肾损伤大鼠的保护作用可能与其减少自由基产生,提高抗氧化能力,上调肾脏eNOS蛋白,下调iNOS蛋白,恢复eNOS/iNOS表达的异常有关,且疗效优于单用Ses和VE。

AIM： To investigate the protective effects of sesamin combined with vitamin E on chemically-induced renal injury and its modula- tion of the expression of endothelial nitric oxide synthase （eNOS） and inducible nitric oxide syn- thase （iNOS） in rats. METHODS： Twenty-eight Sprague-Dawley （SD） rats were used to estab- lish kidney impaired model by using D-gal （ 180 mg·kg^-1 · d^-1, i. p.） and A1C13 （15 mg·kg^-1 · d^-1,i.g.） for 20 weeks. A sin- gle dose of either Ses （160 mg·kg^-1 · d^-1） or VE （10mg·kg^-1 · d^-1） and combined dose of Ses ＋ VE （ 160 mg·kg^-1 · d^-1 and 10 mg·kg^-1 · d^-1） were given to rats at 13th week post-renal injury induction for 8 consecu- tive weeks, while control rats were given NS （5.0 mL. kg-1 ~ d-1）. Bilateral kidneys from each rat were isolated to determine wet weight, nitric oxide （NO） and malondialdehyde （MDA） contents, the activities of total antioxidant ca- pacity （T-AOC） and superoxide dismutase （SOD） were also determined at the end of the experiment. Hematoxylin ＆ eosin （HE） and Masson stain were used to observe the renal morphology and collagen deposition. Immuno- histochemical technique and western blotting were employed respectively to detect the iNOS and eNOS expression. RESULTS： As compared with the model rats, the levels of NO, SOD and T-AOC were significantly increased, and the MDA content was decreased in rats treated with Ses and （or） VE. The positive expression of eNOS was apparently up-regulated by down-reg- ulating the iNOS level and the effects of Ses plus VE was better than single Ses or VE group（P〈 0. 05,P〈0. 01）. CONCLUSION： The renopro- tective effect of sesamin combined with vitamin E on chemically-induced renal injury in rats could be associated with decrease in free radical generation, increase in anti-oxidant activity, promotion of eNOS, inhibition of iNOS activity, restoration of eNOS/iNOS balance, Ses plus VE treatment was more effective than Ses or VE given as a single treatment （monotherapy）.