Bone Marrow Stromal Cells (BMSCs) Inhibit Retinal Ganglion Cell Apoptosis and Alleviate Inflammation Through Up-Regulation of MicroRNA-43 and Brain-Derived Neurotrophic Factor in Glaucoma

Glaucoma is a leading cause of vision loss mainly due to retinal ganglion cells (RGC) loss. MicroRNAs (miRNAs) are highlighted as potential biomarkers in diseases. This study aims to investigate the role of miR-43 and BMSCs in the RGC apoptosis and glaucoma.RGCs were transfected with miR-43 inhibitors and mimics, and then co-cultured with BMSCs. RT-qPCR analysis was conducted to determine miR-43 expression, whilst Western blot, and flow cytometry were carried out to assess the role of miR-43 in apoptosis and inflammation. The interaction between miR-43 and BDNF, a neurotrophic factor, was detected by dual-luciferase reporter gene assay. Overexpression of miR-43 promoted RGC proliferation and decreased apoptosis. Furthermore, miR-43 overexpression diminished the contents of apoptosis- and inflammatory-related factors, and elevated the expression of BDNF. Down-regulation of BDNF exerted similar effect as down-regulation of miR-43, enhancing apoptosis and aggravating inflammation. Importantly, BMSC treatment reversed the in vitro inhibitory effect of si-BDNF on RGC with enhancement of miR-43 expression. Mechanically, miR-43 was indicated to target BDNF in glaucoma. Collectively, miR-43 delivered by BMSCs plays an important role in the inflammatory injury and abnormal apoptosis of RGC by regulating the expression of BDNF. These findings might help development of new treatment for glaucoma and provide a promising biomarker for diagnosis and treatment.