同型半胱氨酸对小鼠糖异生作用的影响

目的研究高同型半胱氨酸血症中肝脏组织葡萄糖-6-磷酸酶（G6Pase）和磷酸烯醇式丙酮酸羧激酶（PEPCK）的表达，探讨
同型半胱氨酸对糖异生作用的影响。方法50 只小鼠随机分为高同型半胱氨酸血症（HHcy）组和正常对照组，每组25 只；含
1.5%的蛋氨酸饮水3个月制造高同型半胱氨酸动物模型。3个月后，各组测定空腹血糖、空腹胰岛素，计算胰岛素抵抗指数；利
用逆转录PCR（RT-PCR）和Western blot方法检测肝脏的G6Pase和PEPCK表达的变化。结果与正常对照组比较，HHcy组空腹
血糖、空腹胰岛素和胰岛素抵抗指数增加（P<0.05）；RT-PCR发现HHcy组肝脏的G6Pase和PEPCK的mRNA水平明显增加（P<
0.05）；Western blot表明HHcy组肝脏的G6Pase和PEPCK的蛋白质表达水平明显增加（P<0.05）。结论同型半胱氨酸可能通过
增强糖异生作用，导致肝糖的输出增多，与胰岛素抵抗的发生有关。

Effect of homocysteine on gluconeogenesis in mice

Objective To investigate the expressions of glucose-6-phosphatase (G6Pase) and phosphoenolpyruvate
carboxykinase (PEPCK) in the liver of mice with hyperhomocysteinemia (HHcy) and explore the mechanism of
gluconeogenesis induced by homocysteine. Methods Fifty mice were randomly divided into normal control group (n=25) and
HHcy group (n=25) and fed with normal food and food supplemented with 1.5% methionine, respectively. After 3 months of
feeding, the fasting blood glucose and insulin levels were determined, and HOMA insulin resistance index (HOMA-IR) was
calculated. The expressions of G6Pase and PEPCK in the liver of mice were detected using RT-PCR and Western blotting.
Results The fasting blood glucose and insulin levels and HOMA-IR were significantly higher in HHcy group than in the
control group (P<0.05). RT-PCR and Western blotting showed that the hepatic expressions of G6Pase and PEPCK mRNA and
proteins increased significantly in HHcy group compared with those in the control group (P<0.05). Conclusion Homocysteine
promotes gluconeogenesis to enhance glucose output and contribute to the occurrence of insulin resistance.