Study On The Mechanism Of Myostatin Mutation Improve The Antioxidant Capacity Of Bovine Muscles

Myostatin（Mstn）affects muscle growth and development,and regulates muscle glucose metabolism through multiple signaling pathways such as PI₃k-akt and AMPK.In the present study,the soleus muscles were collected respectively from13-month old MT and control Luxi cattle,and the transcriptome,glucose metabolism,antioxidant system and reactive oxygen species were analyzed.The results showed that,（1）MSTN mutation resulted in significant changes in the soleus transcriptome;（2）MSTN knockout affected the glucose metabolism,increased the G6PD activity,enhanced the pentose phosphate pathway（PPP）,and produced more NADPH;（3）MSTN mutation produced high proportion of reduced glutathione and alleviated the ROS damage to the muscles;（4）Mutation of MSTN down-regulated SMAD pathway and up-regulated AMPK signaling pathway;（5）MSTN mutation decreased the inhibition of Smad on AMPK and promoted G6PD phosphorylation.In conclusion,the soleus muscle derived from MT cattle occurred significant changes in glucose metabolism,improved pentose phosphate pathway,and led to enhanced antioxidant capacity of the muscles.The mechanism involved in this change was probably that Mstn mutation enhanced AMPK activity,which subsequent promoted G6PD phosphorylation and increased the pentose phosphate pathway.