因宁片对甲亢大鼠肝细胞凋亡调节蛋白Caspase-3和Bcl-2表达的影响

Influence of Yinning Tablet on Expression of Caspase-3 and Bcl-2 Proteins Related to Apoptosis Regulation in Rat Liver with Hyperthyroidism

目的观察因宁片对甲亢大鼠肝细胞凋亡调节蛋白半胱天冬酶-3(Caspase-3)和B细胞淋巴瘤/白血病-2(Bcl-2)表达的影响,探讨因宁片对甲亢肝损害的保护作用及其机制。方法对SD大鼠灌胃甲状腺片1.2 g/(kg.d)制备甲亢肝损害模型。因宁片低(0.6 g/kg)、中(1.2 g/kg)、高(2.4 g/kg)剂量组和甲亢灵组(1.2 g/kg)均灌胃给药,治疗30 d后处死大鼠,取血和肝脏。用放射免疫法测血清三碘甲状腺原氨酸(T3)、甲状腺素(T4)、促甲状腺激素(TSH),全自动生化仪测血清天门冬酸氨基转移酶(AST)、丙氨酸氨基转移酶(ALT),Western-Blot检测Caspase-3蛋白、Bcl-2蛋白表达。结果与空白对照组相比,模型组大鼠血T3和T4水平明显升高,TSH水平下降(P<0.01),AST和ALT水平升高(P<0.01),Caspase-3蛋白表达明显升高,Bcl-2蛋白表达显著下降(P<0.01)。与模型组比较,因宁片高、中、低剂量组血中T3,T4,AST,ALT水平均明显降低,TSH水平均明显升高(P<0.05),因宁片高、中剂量组Caspase-3蛋白表达明显下调(P<0.01和P<0.05),Bcl-2蛋白表达明显上调(P<0.01),且因宁片高剂量组的改变最明显。结论因宁片对甲亢合并肝损害有预防作用,其作用机制可能与抑制肝细胞凋亡有关。

Objective To investigate the effect of Yinning Tablet on expression of Caspase-3 and Bcl-2 proteins related to apoptosis regulation in rat liver with hyperthyroidism.To assess the protective function and possible mechanism of Yinning Tablet on liver dysfunction induced by hyperthyroidism.Methods SD rats were perfused intragastrically with Thyroid Tablet（1.2 g/kg） to establish the rat model of liver injury induced by hyperthyroidism.Rats were treated with Yinning Tablet at 0.6,1.2,2.4 g/kg and Jiakangling at 1.2 g/kg for 30 d,respectively.After treatment,blood samples and liver were immediately collected.The serum contents of T3,T4 and TSH were assayed by RIA,the levels of ALT and AST were determined by automatic biochemical analysator.The expressions of Caspase-3 and Bcl-2 in liver were detected by Western Blot.Results In comparison with those in the control group,the serum contents of T3,T4 and the serum levels of ALT and AST and the expression of Caspase-3 in liver were increased significantly（P 0.01）,but the content of TSH and the expression of Bcl-2 were markedly decreased in hyperthyroidism model group（P 0.01）.Yinning Tablet in high,middle and low doses treatment groups markedly down-regulated the levels of serum T3,T4,ALT and AST,but the TSH content was elevated compared with hyperthyroidism model group（P 0.05）.Administration of Yinning Tablet with high and middle doses up-regulated Bcl-2 expression and down-regulated Caspase-3 expression（P 0.05 or P 0.01）,and high dose group of Yinning Tablet was altered most markedly.Conclusion Yinning Tablet plays a protective role in the pathogenesis of the liver dysfunction induced by hyperthyroidism.It is proposed that the effect is concerned with antiapoptotic pathways.