抄録
To investigate the effects of the JAK2/STAT3 pathway on skeletal muscle development and energy metabolism, AG490 and IL-11 were used as agonist and inhibitor in treating mice and the mouse skeletal muscle cells. Average body weight (ABW) was reduced significantly in the mice treated with AG490 (p<0.05), while IL-11 had the opposite effect (p<0.05), as compared with the controls, average body temperature (ABT) remained at normal levels in both groups. Western blotting was used to determine the protein levels of JAK2, STAT3, p-JAK2, and p-STAT3. AG490 caused significant decreases in p-JAK2 and p-STAT3 (p<0.05), while IL-11 did the opposite (p<0.05, p<0.01). Quantitative RT-PCR also showed significantly decreased expression levels of Myf5, MyoD, LXRa, and UCP3 in the AG490 group (p<0.01), but in the IL-11 group, the expression of Myf5, MyoD, and UCP3 was increased (p<0.05), except that LXRa whose expression did not change. In cultured skeletal muscle cells, the expression of MyoD, Myf5, LXRa, and UCP3 (p<0.05) exhibited the same trend as that in the skeletal muscles of both treated groups (p<0.05). These results implicate the JAK2/STAT3 in skeletal muscle development and energy metabolism.
