The Effects Of Exercise Preconditioning On Serum -free Mtdna And Mitochondrial Autoimmunity In Mice

Abstract

PURPOSE: To explore the effects of exercise preconditioning on serum free mtDNA and mitochondria-associated immune proteins in skeletal muscles under acute centrifugation injury. METHODS: Eight-week-old C57BL male mice were randomly divided into three groups according to their body weight. Each group consisted of 6 mice (NC, RC, RE). Exercise pre-adaptation program: take a non-slope 20 m/min treadmill training for 40 min/d, training for 6 weeks. Acute Sports Injury Program: In the 6th week of exercise training in RE group, 3 days of 10 m/min and 5 minutes of adaptive training without gradients on the RC group were started in the RC group; all mice in the RC and RE groups took 16 m/min,-16 ° Downhill running, training 90 min. After 16 hours of injury training, the mice were sacrificed, and one side of the gastrocnemius muscle was fixed with paraformaldehyde and awaited for HE staining. The tissue samples were detected by PCR, RT-PCR, Western Blotting, and ELISA. RESULTS:1) Serum free mtDNA content in RC group was significantly higher than NC and RE group (P < 0.05) 2) IL6 levels in mouse serum were significantly lower in NC group than in RC and RE group (P < 0.05, P < 0.01); The group was significantly higher than the NC group and RE group (P < 0.05, P < 0.01); 3) The results of STING mRNA detection showed that NC group was higher than RE (P < 0.05) There was no significant difference between RC group and RC group, but RC group was significantly higher than that of RE group (P < 0.01). The results of mRNA expression tests of other molecules in STING pathway showed that only IRF3 expression was significantly lower in RE group than in NC group. (P < 0.05);4) The expression of PINK1 in skeletal muscle was highest in the RC group and significantly higher than that in the RE group (P < 0.01). Parkin was the highest in NC group in skeletal muscle, (P < 0.01). CONCLUSIONS: (1) Increase in serum free mtDNA content caused by acute centrifugation injury exercise is not a cause of inflammatory reaction to skeletal muscle injury, because acute centrifugation injury inhibits the transcription of mitochondria-associated immune proteins in skeletal muscle, and cGAS-STING-TBK1-IRF3 - The IFN-β signaling pathway is not activated. (2) Acute centrifugal injury exercise and exercise preconditioning did not affect PINK1/Parkin-mediated mitochondrial autophagy.