Metformin inhibits apoptosis by regulating TET2-Foxo3a pathway after spinal cord injury / 中华骨科杂志

ABSTRACT

Objective:Through TTC staining, immunohistochemical analysis, RT-PCR and hind limb motor function evaluation and other experimental methods, to explore the regulatory mechanism of metformin on anti-apoptosis in rats with spinal cord injury (SCI).Methods:Establish a rat spinal cord injury model. Through Basso-Beattie -Bresnahan locomotor rating scale (BBB) and cant test to evaluate the recovery of hindlimb motor function in rats. The changes of necrotic area of spinal cord tissue were compared by TTC staining. Extraction of rat spinal cord tissue, by Dot blot analysis and immunohistochemical detection of the hydroxyl of DNA methylation level. By qPCR, Western Blot detection TET2mRNA and protein expression level, and the changes in the scope of spinal cord injury were detected by inhibiting the expression of TET2. The interaction between TET2 and Foxo3a was detected by immunoblotting and immunoprecipitation. Through RT-PCR assay Foxo3a downstream related changes in the level of gene expression.Results:Compared with the SCI+NS group, the necrotic area of the spinal cord tissue was reduced after metformin treatment, and the BBB score and the incline test score were higher ( P<0.05). At the same time, we found that the levels of TET2mRNA and protein increased significantly after SCI at 24 h, and the 5-hmC level of DNA increased. The levels of TET2mRNA and protein and 5-hmC increased further after the use of metformin. After using SC-1, compared with the SCI+MET group, the level of 5-hmC decreased and the area of infarction increased. After SCI, the mRNA levels of downstream genes Bim, P27kip, Bax increased significantly. After metformin treatment, the mRNA levels of Bim and Bax were lower than those in the SCI+NS group ( P<0.05). After SCI, the 5-hmC levels of downstream genes Bim, P27kip, Bax increased significantly. After metformin treatment, the 5-hmC levels of Bim and Bax were lower than those in the SCI+NS group ( P<0.05). Conclusion:Metformin can promote the interaction between TET2 and Foxo3a, increase the 5-hmC level of the overall DNA, and inhibit the activation of related apoptosis genes, thereby improving tissue damage and nerve function recovery after spinal cord injury.