妊娠期糖尿病胎鼠肺组织中p-mTOR、HIF-1α及VEGF-A表达的研究

Expression of p-mTOR、 HIF-1 and VEGF-A in Lung Tissue of Ges- tational Diabetes Mellitus Rats

目的探讨高血糖对胎鼠肺组织中磷酸化雷帕霉素靶蛋白（phosphorylation mammalian target of ra-pamycin，p-mTOR）、缺氧诱导因子．1仅（hypoxia inducible factor-1α，HIF-1α）及血管内皮生长因子A（vascular endothelial growth factor-A，VEGF-A）蛋白表达的影响及意义。方法妊娠大鼠分成实验组（糖尿病组，GDM组）、干预组（糖尿病模型＋雷帕霉素）及对照组（柠檬酸缓冲液）。光镜下观察各组孕21d胎鼠肺组织的大体形态结构；利用免疫组化技术检测各组胎鼠肺组织中p-mTOR、HIF-1α及VEGF-A的定位表达；Western印迹技术检测胎鼠肺组织中p-mTOR、HIF-1α、VEGF-A蛋白水平；RT．PCR技术检测胎鼠肺组织中HIF-10l、VEGF-AmRNAs水平。结果免疫组化及Western印迹结果显示，与对照组相比。糖尿病组p-mTOR、HIF-1α、VEGF-A在胎鼠肺组织中的表达水平明显增加，干预组中各蛋白表达水平与GDM组相比显著降低。RT-PCR结果显示，与对照组相比，糖尿病组中p-mTOR、HIF-1α、VEGF-AmRNAs相对平均量显著增加，干预组中各基因mRNAs水平与GDM组相比显著降低。结论妊娠期糖尿病高血糖可导致胎鼠肺组织中异常激活的p-roTOR及其调控因子HIF-1及VEGFA表达增高，可能与胎鼠肺血管的发育异常相关。

Objective investigate the effect of hyperglycemia on the expression of p-mTOR, HIF-1 and VEGF-A vascular endothelial growth factor （VEGF） in fetal rat lung. Methods Pregnant rats were divided into experimental group （diabetic group ）, intervention group （diabetic model ＋ rapamycin） and control group （citric acid buffer） . The gross morphological structure of fetal lung tissue was observed under light microscope for 21 days ; The expression of p-mTOR, HIF-1 txand VEGF-A in fetal lung tissue was detected by immunohistochemistry; The expression level of p-mTOR, HIF-1α and VEGF-A protein in fetal lung tissue was detected by Western Blot technique, and the expression level of HIF-1 ctand VEGF-A in fetal lung tissue was detected by RT-PCR tech- nique. Results Compared with the control group, the alveolar cavity decreased and the number in- creased, the alveolar septum thickened and the fetal lung structure poorly developed in the DM group and the intervention group. Immunohistochemical and Western Blot results showed that, com- pared with the control group, the expression of P-mTOR, HIF-1 aand VEGF-A in the fetal lung tis-sue was significantly increased in the diabetic group, The protein expression level of the intervention group was between the control group and the diabetes group. RT-PCR results showed that compared with the control group, the relative average of HIF-1α Land VEGF-A mRNAs in the GDM group decreased significantly, while the level of HIF-1 otand VEGF-A mRNAs in the intervention group was significantly lower than that in the GDM group. Conclusion Hyperglycemia in gestational diabetes mellitus can induce abnormal activation of p-mTOR and its regulators, HIF-1α and VEGF-A, infetal lung tissues. It may be related to abnormal development of fetal pulmonary vessels.