The expression patterns of FoxO3a and MuRF-1 in the myocytes of denervated gastrocnemius muscle in rats

Objective To investigate the expression patterns of FoxO3a and MuRF-1 in the myocytes of denervated gastrocnemius muscle in rats. Methods Seventy-two Wistar rats were randomly divided into 12 groups with 6 rats each.The right sciatic nerve was transected while the left underwent a sham operation.One group of rats was sacrificed at postoperative day0,1,2,3,4,5,6,7,10,14,21 and 28 respectively to harvest the right gastrocnemius muscles.The samples were frozen at - 70℃.Real-time PCR was used to detect the mRNA level of FoxO3a and MuRF-1,and western blot was done to detect the protein concentration of FoxO3a and MuRF-1 for each sample. Results The mRNA level of MuRF-1 reached its peak at 4 days after the denervation (18.12 folds),and returned to normal level after 14 days.The mRNA level of FoxO3a peaked at 6 days after the denervation (7.06 folds),while maintaining at a high level despite the slow decline.The protein concentration of FoxO3a and MuRF-1 increased with the days of denervation. Conclusion The expressions of FoxO3a and MuRF-1 are closely related to the process of muscle atrophy after denervation.Both FoxO3a and MuRF-1 can be the targets for drug treatment or gene therapy to delay denervation atrophy. Key words: Muscle atrophy;  Rats;  Denervation;  FoxO3a;  MuRF-1