Effect Of Corn Peptide Ingestion And Exercise On Protein Metabolism In Skeletal Muscle Of Obese Rats And Its Possible Mechanism

Objective: To explore the effect of Corn peptide with or without treadmillexercise on protein metabolism in skeletal muscle of obese rats.Methods: Male Sprague-Dawley rats (n=135) were fed a high-fat diet for8w as a dietary induced obesity model (DIO, n=40). Then randomly dividedinto five groups. DIO control, DIO+Casein group, DIO+CP group, DIO+exercise group and DIO+CP+exercise group (n=8, each group). Other rats(n=15) were fed a balanced diet as a normal group. Supplement (CP:200g/kg diet; Casein: dietary protein content is equal to CP diet) andexercise (Treadmill Ex was performed15m/min for60min/d,6days aweek) were executed as protocol for4w. At the end of4w, rats of all groupswere sacrificed. TG, TC, LDLC, HDLC, lipid and hormone were measuredfrom plasma. TNF-a, P-mTOR/mTOR, P-p70s6k/p70s6k and P-rps6/rps6expression were measured by Western-blotting from muscle.Results: After4w, compared with DIO control group, body weight andperirenal fat mass index in DIO+CP+exercise group significantly decreased(P <0.05) and soleus mass index was significantly increased (P<0.05). TG,insulin and leptin in DIO+CP+exercise group were significantly decreased(P<0.05). And P-mTOR/mTOR, P-p70s6k/p70s6k and P-rps6/rps6expression of muscle were all significantly increased (P<0.05).Conclusion: Corn peptides consumption with exercise could promoteprotein synthesis of skeletal muscle in obese rats through activating mTORsignaling pathway.