The Effect Of JAK2/STAT3 Signal Pathway On The Expression Of Skeletal Muscle Development And Energy Metabolic Related Genes In Mice

Janus Kinase2/Signal transducers and activators of transcription3 (JAK2/STAT3) signal pathway is a recent research focus, which has myocardial protect function and plays an important role in cell growth, differentiation and apoptosis. In addition, the pathway could regulate metabolism of animal fat. But there are less research on this pathway in skeletal muscles. In this study, Kun Ming mice and mouse skeletal muscle were taken as study object, which were treated with AG490 and IL-11. Body weight change, body temperature and oxidative enzymes (SOD,CAT,MDA and GSH-PX) activity were measured, and JAK2,STAT3,MyoD,Myf5,LXRα,UCP3,PPARγ,FAS and HSL gene expression were detected by using Real-time PCR, to analysis the effect of JAK2/STAT3 signaling pathway in mouse skeletal muscle development, energy metabolism and oxidative enzyme activity.1 To study the effects of JAK2/STAT3 signal pathway on the expression of muscle development and energy metabolic related genes by inhibiting this pathway using AG490. The tentative male Kunming mice were treated with intraperitoneal injection of AG490 for two weeks. After execution, the leg muscle was surgically removed and total RNA was extracted. Real-time quantitative PCR was used to examine the expression of the key factors in JAK2/STAT3 signal pathway (JAK2,STAT3), the growth related genes of skeletal muscle(MyoD,Myf5), and energy metabolic related gene(sLXRα,UCP3). Compared with control, in the treatment group, the body weight of mice were significantly decreased (P<0.05); the body temperature was stable; the expression of JAK2 and STAT3 were significantly decreased(P<0.05); the expression level of LXRα,UCP3,MyoD and Myf5 were decreased extremely significant (P<0.01). JAK2/STAT3 signal pathway might regulate the growth of skeletal muscle and energy metabolism by decreasing the expression levels of the growth of skeletal muscle development and energy metabolic related genes.2 To study the effects of JAK2/STAT3 signal pathway on the expression of muscle development and energy metabolic related genes by activating this pathway using IL-11. The tentative male Kunming mice were treated with intraperitoneal injection of IL-11 for two weeks. After execution, the leg muscle was surgically removed and total RNA was extracted. Real-time quantitative PCR was used to examine the expression of the key factors in JAK2/STAT3 signal pathway, JAK2 and STAT3, the growth related genes MyoD and Myf5, and energy metabolic related genes LXRαand UCP3. Compared with control group, the mice weight of muscle and body were significantly increased in the treatment groups (P<0.05); body temperature was stable in the reasonable rang; the expression of STAT3 and JAK2 were significantly increased (P<0.05); the expression level of MyoD和Myf5 were significantly increased(P<0.05); the expression of LXRαwas slightly up-regulated (P>0.05)and UCP3 expression increased (P<0.05). The results indicated that JAK2/STAT3 signal pathway might regulate the growth of skeletal muscle and energy metabolism by increasing the expression levels of the skeletal muscle development and energy metabolic related genes.3 Mice were respectively treated with IL-11 and AG490. The results showed that in IL-11 treatment group, the expression of genes PPARγincreased significantly (P<0.05), FAS and HSL expression were unchanged (P>0.05); CAT,GST-PX and SOD activity decreased significantly (P<0.05), MDA content was significantly increased (P<0.05). In AG490 treatment group, PPARγ,FAS and HSL expression decreased significantly (P<0.05); CAT,GST-PX and SOD activity significantly decreased (P<0.05), but the MDA content significantly increased. The results showed that JAK2/STAT3 signaling pathway may be involved in regulating muscle fat deposition, Also affect the activity of tissues of the body play an important role in protect the organization.4 Skeletal muscle cells were respetively treated with 15μg/mL AG490 and 10 ng/mL IL-11, In AG490 treatment group, JAK2 and STAT3 expression significantly decreased (P<0.05); MyoD and Myf5 expression significantly decreased (P<0.05); LXRаand UCP3 expression significantly decreased (P<0.05). In IL-11 treatment group, JAK2 and STAT3 expression significantly increased (P<0.05); MyoD and Myf5 expression increased significantly (P<0.05); LXRаgene expression did not change significantly(P>0.05), UCP3 expression significantly increased (P<0.05). The results certificated that JAK2/STAT3 pathway relates to skeletal muscle development and energy metabolism at the cell level.