Gαi1/3介导肝细胞生长因子信号转导促视网膜血管新生作用机制研究

早产儿视网膜病变（ROP）中肝细胞生长因子（HGF）升高促视网膜血管新生（RNV）。预实验发现小鼠视网膜血管内皮细胞（RVEC）中HGF诱导其受体MET和Gαi1/3耦联。Gαi1/3 shRNA抑制HGF信号转导及RVEC成管、增殖和迁移。OIR模型鼠视网膜组织中HGF-MET上调；小鼠玻璃体腔注射Gαi1/3 shRNA抑制OIR诱导的RNV。人参皂苷Rh2（GRh2）抑制HGF诱导MET-Gαi1/3耦联及下游信号活化。我们提出Gαi1/3介导HGF信号转导促RNV，其作用可被GRh2抑制。本项目将观察OIR模型鼠中HGF、MET、Gαi1/3等表达/活化情况；拟运用shRNA、CRISPR/Cas9、敲除细胞株、基因突变、过表达等方法解析Gαi1/3介导HGF信号转导促RNV的作用及分子机制；体内外研究GRh2抗HGF诱导RNV的作用。为ROP等RNV相关眼病提供治疗新靶点。

In the progression of retinopathy of prematurity (ROP), elevated HGF can promote retinal neovascularization (RNV). Our preliminary results show that in mouse retinal vascular endothelial cells (RVEC), HGF induced MET (the HGF receptor)-Gαi1/3 association. Conversely, Gαi1/3 shRNA inhibited HGF-induced downstream signal transduction as well as RVEC tube formation, proliferation and migration. In the retinal tissues of oxygen-induced retinopathy (OIR) mice, expression of HGF and MET was significantly increased. Whereas intravitreal injection of Gαi1/3 shRNA lentivirus inhibited OIR-induced RNV in mice. Further studies show that ginsenoside Rh2 (GRh2) inhibited HGF-induced MET-Gαi1/3 association and downstream signal activation. We propose that Gαi1/3 mediate HGF signal transduction to promote RNV, which could be inhibited by GRh2. In the current proposal, we will test the expression and/or activation of HGF, MET and Gαi1/3 in the retinas of OIR mice. By using strategies including shRNA, CRISPR/Cas9, knockout cell lines, gene mutation and overexpression, we will focus on the role and the underlying mechanisms of Gαi1/3 in mediating HGF-MET signal transduction pro-RNV activity. We will also explore the inhibitory activity of GRh2 on HGF-induced RNV both in vitro and in vivo. The results of the study shall provide novel therapeutic targets for ROP and other RNV-associated ophthalmic diseases.