因宁片对甲亢性肝损害大鼠肝脏的甲状腺激素受体和Ⅰ型脱碘酶基因表达的影响

Effect of Yinning Tablet on Gene Expressions of Thyroid Hormone Receptor and Type Ⅰ Iodothyronine Deiodinase in Liver Tissues of Rat with Hyperthyroidism Liver Damage

关键词:  因宁片  甲状腺功能亢进  肝损害  大鼠  甲状腺激素受体  Ⅰ型脱碘酶  实时荧光定量PCR

Key words:  Yinning tablet  hyperthyroidism  liver damage  rat  TR  DioⅠ  real-time quantitative PCR

摘要:

目的 研究因宁片对甲亢性肝损害大鼠的肝组织内甲状腺激素受体(TR)和Ⅰ型脱碘酶(DioⅠ)基因表达的影响。方法 采用L-甲状腺激素钠(800 mg·kg^-1·d^-1)灌胃建立大鼠甲亢性肝损害模型。给予因宁片低(0.6 g·kg^-1·d^-1)、中(1.2 g·kg^-1·d^-1)、高(2.4 g·kg^-1·d^-1)剂量、甲亢灵(1.2 g·kg^-1·d^-1)，灌胃给药30 d后，处死大鼠。取部分肝脏通过实时荧光定量PCR方法检测肝组织中TRa1、TRa2、TRb1、DioⅠ基因的表达变化，酶联免疫吸附法(Elisa)法检测肝组织中DioⅠ含量，Chapra氏方法测定肝组织DioⅠ的活性。结果 与空白对照组比较，模型组TRa1表达上调，TRa2表达下调，TRb1表达上调(P<0.01)；因宁片能抑制TRa1和TRb1基因表达(P<0.05)，对TRa2表达影响不明显(P>0.05)。模型组DioⅠ表达与空白对照组相比显著增强(P<0.01)，含量增加(P<0.01)、活性升高(P<0.05)；与模型组比较，因宁片能显著降低DioⅠ表达，并呈剂量依赖趋势(r=-0.792，P<0.01)，各剂量组均降低DioⅠ含量(P<0.05或P<0.01)，因宁片中、高剂量能显著降低DioⅠ活性(P<0.05)。结论 肝组织内TR和DioⅠ表达异常，可能参与甲亢性肝损害的发生。因宁片能调节甲亢性肝损害大鼠肝脏的TR和DioⅠ基因的异常表达、降低DioⅠ含量、抑制DioⅠ的活性，这可能是因宁片治疗甲亢性肝损害的分子作用机制之一。

Abstract:

OBJECTIVE To investigate the effect of Yinning tablet on gene expressions of thyroid hormone receptor (TR) and type I iodothyronine deiodinase (DioⅠ) and activity of DioⅠ in liver tissues of rat with hyperthyroidism liver damage. METHODS Rats were perfused intragastrically with Levothyroxine sodium tablets(800 mg·kg^-1·d^-1) to establish the rat model of hyperthyroidism-induced liver injury. Rats were treated with Yinning tablets at 0.6, 1.2, 2.4 g·kg^-1·d^-1 and Jiakangling at 1.2 g·kg^-1·d^-1 for 30 days, respectively. After treatment, liver samples were immediately collected. The levels of gene expressions of TRα1, TRα2, TRβ1 and DioⅠ in liver tissues were determined by real-time quantitative PCR, meanwhile, the DioⅠ level was detected with enzyme-linked immunosorbent assay, and the activity of DioⅠ was tested with Chopra’s method. RESULTS Compared with control group, the mRNA expressions of TRa1 and TRb1 were up-regulated and the expression of TRa2 was down-regulated(P<0.01), the content and activity of DioⅠ were increased(P<0.01 or P<0.05). Yinning tablet inhibited the the expressions of TRa1 and TRβ1 genes(P<0.05), but no statistical difference was noted on the expression of TRa2(P>0.05). Compared with the control group, the level of gene expression and activity of DioⅠ in model group was significantly increased(P<0.01, P<0.05). Compared with the model group, Yinning tablet significantly inhibited mRNA expression of DioⅠ in a dose-dependent(r=-0.792, P<0.01) way. Yinning tablet in different dosage groups could decrease the level of DioⅠ(P<0.05, P<0.01), Yinning tablet in medium and high groups could significantly reduce DioⅠ activity(P<0.05). CONCLUSION TR and DioⅠ expression in liver tissue might be involved in the occurrence of Hyperthyroidism liver damage. Yinning tablet may adjust the expressions of TR and DioⅠ genes and inhibit the content and activity of DioⅠ in liver tissues of rat with Hyperthyroidism liver damage, which may be one of the molecular action mechanisms through which Yinning tablet prevents Hyperthyroidism liver damage.