Proteína do soro do leite hidrolisado na síntese proteica muscular

Abstract

Supplementation with WPH is used to activate muscle protein synthesis by p-4EBP1 thus increasing body growth. However, it is not clear if WPH is higherin regulation mechanism of protein synthesis.Objective: The purpose of this study was to assess gastrocnemius 4EBP1 activation in Wistar rats fed standart AIN93-G diet supplemented with WPH, WPC and CAS. Methods: Eighty-four Wistar rats were divided into twelve groups and fed one of the following diets for three weeks: a) CAS; b) WPC; c) WPH; Modified AIN93-G diets containing casein, whey protein hydrolyzed and whey protein concentrate as a protein source. The diets were subdivided into 4 groups: sedentary; exercised; sedentary-exhausted and exercised-exhausted. P-4EBP1 phosphorylation was quantified by Western Blot analysis. Free amino acid concentration in muscle was determined by standard methods. ANOVA and post-hoc Duncan were applied to compare the means (significance p<0.05). Results: Phosphorylated 4EBP1 ofWistar rats were increased by feeding the AIN93-G diet with WPH compared to WPC and CAS to sedentary-exhaustive and exercise-exhaustive groups. Feeding WPC and WPH showing increase phosphorylation of 4EBP1 when compared to CAS in the sedentary condition. P-4EBP1showed no difference between any three groups to trained group. BCAA (specifically, Leucine) were significant increaseto WPH group in free amino acid concentration in muscle, compared to WPC and CAS groups. Conclusion:The phosphorylation of 4EBP1 was significantly higher in the gastrocnemius muscle in rats fed to exhaustion and fed WPH, with no significant difference in the rats of the trained group. The data together show that muscle regeneration depends on the appropriate stimulus during exercise, such as the increase in volume and intensity and the consumption of WPH with protein source presents superior results in MPS.