MiRNA-206 Affects the Recovery of Sciatic Function by Stimulating BDNF Activity through the Down-regulation of Notch3 Expression.

Objective: To investigate the effects and mechanisms of microRNA 206 (miRNA-206) on neurological recovery through Notch receptor 3 (Notch3).

Methods: The sciatic functional index (SFI), nerve conduction velocity (NCV), tricipital muscle wet weight (TWW) and cross-sectional area of the muscular fiber, and grip strength of posterior limbs were detected by establishing a model of the sciatic nerve to evaluate the effect of sciatic nerve injury model. miRNA-206 expression in the model was detected by real-time quantitative polymerase chain reaction (qRT-PCR), to regulate the effects of miRNA-206 on the proliferation of gastrocnemius myocytes by Cell Counting Kit-8 (CCK-8).

Results: SFI of the model established by immediate epineurium suture after sciatic nerve resection was in the range of -150% to -100% and TWW, the average area of gastrocnemius myocytes, the NCV, and the grasping power of the hind limbs in the model were all lower than those in the normal group. And in the model, TWW, the average area of gastrocnemius myocytes, NCV, and grip strength of posterior limbs were lower in the normal group, which verified the successful establishment of the model.

Conclusion: Over-expression of miRNA-206 can down-regulate Notch3 expression, and then stimulate brain-derived neurotrophic factor (BDNF) activity to promote the repair and functional recovery of sciatic nerve injury.