Effects of Electroacupuncture on Skeletal Muscle Atrophy-associated Protein in Hind Limbs of Traumatic Spinal Cord Injury Rats / 中国康复理论与实践

ABSTRACT

Objective:To explore the effects and mechanism of electroacupuncture (EA) on expression of myostatin (MSTN), muscle-specific ring finger protein 1 (MuRF1/Trim63), F-box only protein 32 (Atrogin-1/ Fbxo32), myogenic differentiation antigen (Myod) and myogenin (Myog) in traumatic spinal cord injury (TSCI) rats. Methods:A total of 45 adult female Sprague-Dawley rats were randomly divided into sham operation group (n = 12) and operation group (n = 33). The TSCI model was established with the modified Allen's method. After modeling, there were 24 survival rats and they were randomly divided into model group (n = 12) and EA group (n = 12). EA group was electroacupunctured at Dazhui (DU 14), Mingmen (DU 4) and bilateral Zusanli (ST 36) for 10 minutes, once a day, six times a week for 28 days. Basso-Beattie-Bresnahan (BBB) score was tested before modeling, and three days, seven days, 14 days, 21 days and 28 days after modeling. The rats were measured their body mass before and 28 days after modeling. The ratio of gastrocnemius wet mass was calculated; the cross-sectional area (CSA) and fiber diameter were measured by HE staining; the expression of MSTN, Trim63, Fbxo32, Myod and Myog mRNA were tested with real-time quantitative polymerase chain reaction (qPCR). Results:Three days, seven days, 14 days, 21 days, and 28 days after modeling, the score of BBB was lower in the model group than in the sham operation group (P < 0.01); seven days, 14 days, 21 days, and 28 days after modeling, the score of BBB was higher in EA group than in the model group (P < 0.01). Compared with the sham operation group, the mass of rats, the gastrocnemius wet mass, the CSA and the diameter of the muscle fiber were smaller in the model group (P < 0.05), while the expression of MSTN, Trim63, Fbxo32, Myod and Myog mRNA were higher (P < 0.05). Compared with the model group, the mass of rats, the gastrocnemius wet mass, the CSA, the expression of Myod and Myog mRNA were higher (P < 0.05) in EA group, while the expression of MSTN, Trim63 and Fbxo32 mRNA were lower (P < 0.05). Conclusion:EA might delay the gastrocnemius atrophy in TSCI rats by down-regulating the expression of MSTN, Trim63, Fbxo32 mRNA and up-regulating the expression of Myod and Myog mRNA via controlling the differentiation of the muscle satellite cells and the degradation of protein in skeletal muscle cells.