Abstract: Objective To study the effect of miR-499a-5p on injury induced by chemical hypoxia of pheochromocytoma cell(PC12). Methods PC12 cells were divided into control group, hypoxia group (treated with CoCl2 for 24 h), hypoxia+miR-NC or miR-mimic groups. Cell viability was detected by MTT assay; the expression of miR-499a-5p was detected by RT-qPCR; lactate dehydrogenase (LDH) activity was detected by kit; apoptosis was detected by flow cytometry; the expression of phosphatase and tensin homolog (PTEN) protein was detected by Western blot. The luciferase reporter gene was used to detect whether Pten was a direct target of miR-499a-5p. Results Compared with control group, the cell viability and miR-499a-5p expression decreased (P＜0.01 or P＜0.001), LDH activity and apoptosis increased (P＜0.01 or P＜0.001) in hypoxia group. Over-expression of miR-499a-5p enhanced survival rate and inhibited apoptosis of PC12 cells under hypoxia (P＜0.05 or P＜0.01). Pten was a direct target of miR-499a-5p. Conclusions miR-499a-5p alleviates hypoxic injury of PC12 cells through targeting at Pten.

Key words: miR-499a-5p, phosphatase and tensin homolog, PC12 cell, hypoxic injury