DNA Methylation and Muscle Fiber Configuration on Skeletal Muscle in Spastic Paralysis Rats / 中国康复理论与实践

ABSTRACT

Objective To investigate the DNA methylation of skeletal muscle in spastic paralysis rats and correlation with the muscle fi-ber configuration. Methods 100 5-day old Wistar rats were randomly divided into model group and control group. The former was estab-lished the spastic paralysis modle and reared for 30 days. Then, tissues from the gastrocnemius of all the rats were observed with triplicate DNA methylation, myosin heavy chain-I (MHC-I) mRNA with RT-PCR and transmission electron microscopy. Results The DNA methyla-tion was (4.95 ± 0.83) × 10%in the model group, significantly less than (6.59 ± 0.75) × 10%in the control group (P<0.001);while the MHC-I mRNA was (1.23±0.31), significantly more than (0.44±0.29) in the control group (P<0.001). The Z-line was disordered, and the mitochon-dria near the Z-line increased, with edema and partially broken in cristae. The balance between the thick and thin filaments was broken, and myofibrils envelope fused. Conclusion Hypomethylation and hyperexpression of MHC-I mRNA have been found in skeletal muscle of spas-tic paralysis rats, which may result in type I fibers increase. However, there was no sufficient evidence to support the correlation between the DNA methylation and the secondary pathological changes.