Apigenin inhibits angiogenesis of retinal microvascular endothelial cells by regulating miR-140-5p/HDAC3- mediated PTEN/PI3K/AKT pathway

Abstract Background: Diabetic retinopathy (DR) is the main reason of visual impairment. Apigenin has anti-angiogenic effects in a variety of diseases. Our aim was to explore the role of apigenin in DR and the mechanism involved. Methods: High glucose (HG) induced HRMEC to establish DR model. HRMECs were treated with apigenin. Then we knocked down or overexpressed miR-140-5p and HDAC3, and added PI3K/AKT inhibitor LY294002. miR-140-5p, HDAC3 and PTEN were detected by qRT-PCR. Western blot measured HDAC3, PTEN and PI3K/AKT pathway related proteins expressions. Cell proliferation and migration were monitored by MTT, wound-healing assay and Transwell assay. Angiogenesis was detected by Tube formation assay. Results: After HG treatment, miR-140-5p expression was repressed and miR-140-5p overexpression suppressed HG-induced HRMECs proliferation, migration and angiogenesis. Apigenin treatment significantly reversed the reduction in miR-140-5p level caused by HG treatment and repressed HG-induced HRMECs proliferation, migration and angiogenesis by elevating miR-140-5p. miR-140-5p targeted HDAC3, and overexpression of miR-140-5p could reverse the up-regulation of HDAC3 expression induced by HG treatment. HDAC3 could bind to the promoter region of PTEN and inhibit its expression, and then knocking down HDAC3 suppressed PI3K/AKT pathway via elevating PTEN level. In addition, apigenin inhibited angiogenesis in DR cell models by regulating miR-140-5p/HDAC3-mediated PTEN/PI3K/AKT pathway. Conclusions: Apigenin inhibited angiogenesis of HG induced HRMECs by regulating miR-140-5p/HDAC3-mediated PTEN/PI3K/AKT pathway. Our study might provide new drugs and new targets for treating DR.