The MAPK signaling pathway mediates the GPR91-dependent release of VEGF from RGC-5 cells.
The MAPK signaling pathway mediates the GPR91-dependent release of VEGF from RGC-5 cells.
复制标题
DOI：
10.3892/ijmm.2015.2195
复制
发表时间：
2015-07
影响因子：
5.4
通讯作者：
Wu Q
中科院分区：
文献类型：
--
作者：
Hu J;Li T;Du S;Chen Y;Wang S;Xiong F;Wu Q
血管内皮生长因子（VEGF）是糖尿病视网膜病变（DR）的主要调节分子之一。在我们以前的研究中，我们证明了糖尿病大鼠视网膜中琥珀酸水平升高，并且琥珀酸受体G蛋白偶联受体91（GPR 91）的敲低抑制了DR早期阶段VEGF的释放并减轻了视网膜血管疾病。我们检测了视网膜神经节细胞系RGC-5中参与GPR 91依赖性VEGF释放的信号通路。用靶向GPR 91的慢病毒小发夹RNA（shRNA）表达载体（LV.shGPR91）感染细胞。免疫荧光染色显示GPR 91主要定位于RGC-5细胞的细胞体中。RT-qPCR、western blot和ELISA分析表明，琥珀酸暴露上调VEGF表达，激活细胞外信号调节蛋白激酶（ERK）1/2、c-Jun N-末端激酶（JNK）和p38丝裂原活化蛋白激酶（MAPK）信号通路，并导致环氧合酶-2（考克斯-2）和前列腺素E2（PGE 2）的释放。GPR 91的敲低抑制ERK 1/2和JNK活性，但不抑制p38 MAPK通路的激活。用LV. shGPR 91和ERK 1/2、JNK和考克斯-2抑制剂转导可抑制考克斯-2表达的增加和PGE 2的释放。VEGF的表达和释放也显示了类似的结果。CCK-8法检测表明，siRNA介导的GPR 91基因敲低可抑制RF/6A细胞的增殖。我们的数据表明，GPR 91通过MAPK/考克斯-2/PGE 2信号通路调节琥珀酸诱导的VEGF释放。
Vascular endothelial growth factor (VEGF) is one of the major regulatory molecules in diabetic retinopathy (DR). In our previous study, we demonstrated that succinate levels were elevated in the retinas of diabetic rats and that the knockdown of the succinate receptor, G-protein-coupled receptor 91 (GPR91), inhibited the release of VEGF and attenuated retinal vascular disorder in the early stages of DR. In the present study, we examined the signaling pathways involved in the GPR91-dependent release of VEGF in the retinal ganglion cell line, RGC-5. The cells were infected with a lentiviral small hairpin RNA (shRNA) expression vector targeting GPR91 (LV.shGPR91). Immunofluorescence staining revealed that GPR91 was predominantly localized in the cell bodies of the RGC-5 cells. RT-qPCR, western blot analysis and ELISA indicated that succinate exposure upregulated VEGF expression, activated the extracellular signal-regulated protein kinase (ERK)1/2, c-Jun N-terminal kinase (JNK) and p38 mitogen-activated protein kinase (MAPK) signaling pathways and led to the release of cyclooxygenase-2 (COX-2) and prostaglandin E2 (PGE2). The knockdown of GPR91 inhibited ERK1/2 and JNK activity, but did not inhibit the activation of the p38 MAPK pathway. The increase in COX-2 expression and the release of PGE2 were inhibited by transduction with LV.shGPR91 and ERK1/2, JNK and COX-2 inhibitors. The expression and release of VEGF showed similar results. Cell Counting Kit-8 (CCK-8) assays revealed that the shRNA-mediated knockdown of GPR91 decreased the proliferation of RF/6A cells cultured in succinate-conditioned medium. Our data suggest that GPR91 modulates the succinate-induced release of VEGF through the MAPK/COX-2/PGE2 signaling pathway.
登录
查看更多内容
影响因子：
--
作者：
Kern, Timothy S.
通讯作者：
Kern, Timothy S.
影响因子：
64.8
作者：
He, WH;Miao, FJP;Ling, L
通讯作者：
Ling, L
影响因子：
4
作者：
Aguiar, Carla J.;Andrade, Vanessa L.;Leite, M. Fatima
通讯作者：
Leite, M. Fatima
影响因子：
4.2
作者：
Matsumoto, Makiko;Suzuma, Kiyoshi;Kitaoka, Takashi
通讯作者：
Kitaoka, Takashi
影响因子：
5.8
作者：
Chuang, Yu-Fan;Yang, Hung-Yu;Hsu, Ming-Jen
通讯作者：
Hsu, Ming-Jen