The mechanism of metallothionein MT1M-mediated PI3K/AKT signaling pathway in the regulation of diabetic retinopathy

Metallothionein (MT1M) is associated with tumors and autoimmune diseases. However, its role in DR has not yet been elucidated. DR and normal rat retinal endothelial cells (RECs) were isolated and cultured. DR Rat RECs achieved gene regulation by transfecting MT1M plasmid. PCR and MTT were used to detect MT1M expression, cell proliferation. Flow cytometry was used to detect cell apoptosis. Lactate dehydrogenase (LDH), superoxide dismutase (SOD) and reactive oxygen species (ROS) were detected by MTT. The expression of VEGF and PI3K/AKT signaling pathway was detected by Western blot. The levels of inflammatory factors TNF-α and IL-1β were detected by ELISA. The results showed that the expression of MT1M was reduced in the RECs of DRC rats compared to the normal control group, cell proliferation was enhanced, SOD activity was reduced, LDH and ROS levels were increased, TNF-α and IL-1β secretion increased, and vascular endothelial growth factor (VEGF), PI3K/AKT expression increased (P < 0.05). However, transfection with MT1M plasmid could significantly inhibit cell proliferation, increase SOD activity, reduce LDH and ROS levels, reduce TNF-α and IL-1β secretion, and reduce VEGF and PI3K/AKT expression (P <0.05). The expression of MT1M is reduced in RECs of DR rats. Up-regulation of MT1M can regulate DR3K/AKT signaling pathway and oxidative/antioxidant balance, alter VEGF expression, inhibit inflammation, regulate the growth and proliferation of RECs, and delay DR lesions.