SHC介导的胰岛信号通路与先天性心脏病的相关性研究

Congenital heart disease (CHD) is one kind of common serious birth defect, the basis of CHD molecular pathology is still not known well. By retrospective analysis, we find that the CHD prevalence in the fetuses (2.99%) with gestational diabetes mellitus mothers increased almost 3 times. It may imply that the high glucose or abnormal insulin pathway maybe affect the development of fetal heart. So we compared the whole gene expressions between the heart tissues of 8 CHD and 4 controls. The significant gene expression differences were found in insulin signal pathway (hsa04910). This expression differences were verified in 28 CHD and 10 controls. It indicated that the insulin signal pathway LAR-SHC-Ras-MAPK is very likely involved in the pathogenesis of CHD. However, because the case-control study is easy influenced by sample sizes and other unanticipated factors, the experiments in vitro or in vivo is necessary to confirm the role of LAR-SHC-Ras-MAPK pathway in CHD. Therefore, in this research, we want to perform the verification experiments in vitro by using RNAi methods to silence the expression of LAR or SHC. The verification experiments in vivo will also be performed by using knockout Rats. While, the experiments were designed for finding whether the high glucose can affect the pathway. At last, we can know whether the down regulation of the genes in LAR-SHC-Ras-MAPK pathway could cause the CHD, and whether the high glucose in mother lead to this down regulation.

先心病是人类最常见出生缺陷之一，其分子病理基础不完全清楚。本研究组通过回顾性分析，发现妊娠期糖尿病孕妇的胎儿患先心病的几率（2.99%）是正常孕妇的3倍。这可能暗示了高糖或某些胰岛素通路影响到胎儿的心脏发育。因此我们选8例房间隔缺损（ASD）患者及4例对照的心房组织行表达谱分析，发现胰岛素的信号通路（hsa04910）包括于其中，其后在28例ASD和10例对照的心房组织中行验证也指出胰岛信号通路LAR-SHC-Ras-MAPK中的基因存在显著差异表达。因病例-对照实验影响因素较多，因此在体外和体内对上述通路的变化进行验证非常必要。本研究拟用细胞系通过RNAi的方法阻断LAR及SHC基因行体外验证，并用基因敲除大鼠行体内验证。同时设计实验讨论高糖和此信号通路的关系，最终回答LAR-SHC-Ras-MAPK通路相关基因的表达下调是否抑制心肌细胞生长。而母体的高糖环境，是否是这一抑制作用的原因。

先心病是人类最常见出生缺陷之一，其分子病理基础不完全清楚。本研究组通过回顾性分析，发现妊娠期糖尿病孕妇的胎儿患先心病的几率（2.99%）是正常孕妇的3倍。这可能暗示了高糖或某些胰岛素通路影响到胎儿的心脏发育。因此我们选8例房间隔缺损（ASD）患者及4例对照的心房组织行表达谱分析，发现胰岛素的信号通路（hsa04910）包括于其中，并且胰岛信号通路LAR-SHC-Ras-APK中的基因存在显著差异表达。因病例-对照实验影响因素较多，因此在体外和体内对上述通路的变化进行验证非常必要。本研究组用细胞系通过RNAi的方法阻断LAR及SHC基因行体外验证，并用基因敲除大鼠行体内验证。同时设计实验讨论高糖和此信号通路的关系。我们的研究结果发现：胰岛素信号通路中，SHC (SHC4) 及其下游的效应基因 Ras-MAPK 等在CHD 患者心脏中表达明显下调，表明胰岛信号可能通过SHC激活Ras_MAPK通路激活细胞的增生与分化参与心脏发育；SHC 基因与胰岛素抵抗可能是妊娠糖尿病胎儿心脏畸形患病率增加的原因之一；通过本研究，希望可以为胎儿在高糖环境中心脏的发育问题提供分子基础，为临床上如何控制血糖或用现有胰岛素抵抗治疗药物来控制或预防先心病的发生打下分子病理基础。