TRB3 基因敲除减轻糖尿病小鼠中骨骼肌萎缩和纤维化的研究.

Objective: To investigate the effect of TRB3 gene knockout on skeletal muscle atrophy and fibrosis in diabetic mice.Methods: Thirty TRB3 knockout(TRB3-/-) mice and 30 C57/BL6J mice were randomly divided into 4 groups, including TRB3 knockout diabetes model group(group A), normal TRB3 knockout control group(group B), normal control group(group C) and diabetes model group(group D). Normal control group mice were fed standard rat feed, and diabetic mice were injected intraperitoneally with low dose of streptozotocin to establish diabetic mice model. The forelimb grip strength test, suspension grid test and muscle function test were performed. Meanwhile, the levels of bone microstructure, anti-type I collagen and anti-type III collagen, atrophy gene MuRF1 and atrophy gene atrophy 1 were determined. Results: The hand grip strength of group A, B and D was significantly lower than that of group C, and the hand grip strength of group D was the lowest(P＜0.05). The inverted hanging time of mice in groups A, B and D was significantly lower than that in group C, and the inverted hanging time of mice in group D was the shortest(P＜0.05). CSA value of muscle function in groups A, B and D was significantly lower than that in group C, and CSA value of muscle function in group D was the lowest(P＜0.05). The bone microstructure indexes BMD, BV/TV, Tb.N and Tb.Th in groups A, B and D were significantly lower than those in group C, and the lowest values were in group D(P＜0.05). The values of Tb.Sp and SMI in group C were significantly higher than those in group C, and the values in group D were the highest(P＜0.05). The levels of anti-type I collagen and anti-type III collagen in groups A, B and D were significantly higher than those in group C, and the levels of anti-type I collagen and anti-type III collagen in group D were the highest(P＜0.05).The levels of atrophy gene MuRF1 and Atrogin-1 in groups A, B and D were significantly higher than those in group C, and the levels of Mu RF1 and Atrogin-1 in group D were the highest(P＜0.05). Conclusion: TRB3 gene knockout significantly reduced skeletal muscle atrophy and fibrosis and increased bone strength in diabetic mice. [ABSTRACT FROM AUTHOR]