丹参酮ⅡA对大鼠肝纤维化的干预作用及其调控Ang Ⅱ的分子机制

Intervention and Molecular Mechanism of Ang Ⅱ Regulation of Tanshinone ⅡA on Liver Fibrosis in Rats

[目的]观察丹参酮ⅡA(tanshinone ⅡA,TSN)对四氯化碳(carbontetrachloride,CCl4)致大鼠肝纤维化的干预作用,并以血管紧张素Ⅱ(angiotensin Ⅱ,Ang Ⅱ)受体为靶点探讨相关的作用机制。[方法]SD大鼠随机分为5组,每组6只。除空白对照组外,其余各组大鼠用CCl4诱导肝纤维化模型。治疗组分别给予剂量为21.3mg/(kg·d)、14.2mg/(kg·d)、7.1 mg/(kg·d)的TSN与5%的黄蓍树胶混悬液,模型组和空白对照组给予等容积的5%黄蓍树胶溶液,灌胃1次/d。用药10周后,测定各组大鼠血清中丙氨酸转氨酶(alanine transaminase,ALT)、天冬氨酸转氨酶(aspartate transferase,AST)、Ang Ⅱ的含量,并对各组大鼠肝组织进行HE染色和羟脯氨酸(hydroxyl proline,Hyp)测定,实时荧光定量逆转录PCR(RT-PCR)和免疫组化法(immunohistochemistry,IHC)分别检测I型胶原蛋白(collagen type I,Col I)、缺氧诱导因子-1α(hypoxia inducible Factor-1α,HIF-1α)、血管内皮细胞生长因子(vascular endothelial growth Factor,VEGF)及血管紧张素Ⅱ 1型受体(angiotensin Ⅱ type 1 receptor,AT1R)的m RNA和蛋白表达。[结果]TSN能明显降低肝纤维化大鼠血清中ALT、AST、Ang Ⅱ的水平,降低肝组织中Hyp的含量,抑制胶原纤维的表达,降低Col I、HIF-1α、VEGF及AT1R各m RNA和蛋白表达。[结论]TSN有明显的抗肝纤维化作用,其机制与改善肝脏微循环、减少细胞外基质合成、抑制胶原纤维密切相关。

[Objective]To study the protective effect of Tanshinone ⅡA（TSN） on hepatic fibrosis in rats induced by carbontetrachloride（CCl4）. [Methods]SD rats were divided into 5 groups with 6 in each group. The hepatic fibrosis rat model was established by CCl4. The rats in TSN groups were ig administrated with TSN（21.3mg/（kg·d）, 14.2 mg/（kg·d）, 7.1 mg·/（kg·d）） and 5% Tragacanth gum mixed suspension, the rats in control and model group with 5% Tragacanth gum mixed suspension, once daily. After ten weeks, the activities of alanine transaminase（ALT）, aspartate transferase（AST）, angiotensin Ⅱ（Ang Ⅱ） were tested, and rat liver tissue was tested by Hematoxylin-eosin（HE） staining,hydroxyl proline（Hyp） testing, immunohisto-chemical detection, Real time RT-PCR method.[Results]TSN can obviously inhibit ALT, AST, Ang Ⅱ rise in liver fibrosis rats serum, reduce Hyp in liver tissue and collagen type I（Col I） content, inhibit the increase of collagen fibers, also can reduce the m RNA transcription level of HIF-1 α, VEGF and AT1 R and protein expression. [Conclusion]TSN has obvious anti liver fibrosis effect, and the mechanism is closely related with improving the hepatic microcirculation, decreasing extracellular matrix synthesis,inhibiting the increase of collagen fiber.