OR-017 Supplementation of Ala-Gln inhibits protein breakdown of skeletal muscle in rats with altitude training through TNF-α/NF-κB/MuRF1 pathway

Objective Objective: To explore the effects of alanyl-glutamineAla-Glnor glutamineGln supplementation on protein metabolism in rat skeletal muscle during simulated altitude trainingand compare the intervention of Gln or Ala-Gln to provide the necessary experimental basis for finding nutritional interventions to inhibit skeletal muscle protein degradation during altitude training. Methods Methods: Forty SD rats aged 6 weeks were randomly divided into normoxic control groupNC groupn=10hypoxic exercise groupHE group n=10hypoxic exercise + glutamine + alanine groupHEG groupn=10 hypoxic exercise + alanyl glutamine groupHEAG groupn=10. Rats were subjected to 6 weeks of 13.6% hypoxic exposure and 90% lactic acid threshold intensity weight-bearing swimmingload weight of 2.1% of body weightexercise training30 minutes after the end of each trainingthe mixed solution of Ala and Gln was administered according to the dose of 0.75g/Kg body weight in HEG groupand the solution of Ala-Gln was administered in the HEAG group at a dose of 1.5 g/kg body weight. After 6 weeksthe contents of rat skeletal muscle total proteinPromyosin heavy chainMyotumor necrosis factor-αTNF-αnuclear transcription factor-κB NF-κBNF-κB inhibitory protein αIkBαand mRNA expression of muscle atrophy box F geneMAFbxmuscle ring finger gene 1MuRF1and inhibitor of kappa B kinase complex-betaIKKβwere measured. Results Results:1Compared with NC groupthe content of Pro and Myo in skeletal muscle in HE group was significantly decreasedP 0.05. The expression of MuRF1 mRNA and the content of TNF-α and NF-κB in skeletal muscle decreasedIkBα content increasedthere were no significant differencebut mRNA expression of MAFbx and IKKβ was significantly decreasedP<0.05 P<0.01. 3Compared with HE groupthe content of Pro and Myo in skeletal muscle in HEAG group increased significantlyP<0.05mRNA expression of IKKβMuRF1 and MAFbP<0.01and TNF-αNF-κB contentP<0.05in skeletal muscle was significantly decreasedand the IkBα content was significantly increasedP<0.05. Conclusions Conclusion:1Simulated altitude training can activate TNF-α/NF-κB/MuRF1 pathway and enhance the catabolism of skeletal muscle proteinwhich is one of the important mechanisms for the reduction of skeletal muscle protein content caused by altitude training. 2Supplementation of Ala-Gln during altitude training can significantly reduce the activation of TNF-α/NF-κB/MuRF1 pathway in skeletal muscleand reduce the catabolism of skeletal muscle protein during altitude trainingwhich plays a very important role in preventing the loss of skeletal muscle protein caused by altitude training. supplementation of Gln monomer during altitude training has little inhibitory effect on the activation of TNF-α/NF-κB/MuRF1 pathway in skeletal muscle.