A Diet Including Red Bell Pepper Juice and Soy Protein Suppress Physiological Markers of Muscle Atrophy in Mice

Abstract

Although muscle atrophy can be caused by disuse and lifestyle-related syndromes, it may be possible to prevent this condition through dietary intervention. We hypothesized that a diet including red bell pepper juice (RBPJ) and soy protein isolate (SPI) would prevent muscle atrophy. Accordingly, an experimental diet containing RBPJ and/or SPI was administered for 18 d to normal C57BL/6J mice. The control group was administered a casein diet. Four days before the end of the test period, denervation-induced muscle atrophy and/or sham operation were performed. Anterior tibialis muscle samples were then obtained to assess muscle degradation and perform metabolome analysis. Under the denervation condition, the 20% SPI diet did not alter the mRNA expression levels of muscle atrophy marker genes compared with the 20% casein group. Although the diet comprising RBPJ and 20% casein did not prevent muscle atrophy compared with the control group, the diet containing RBPJ and 20% SPI did. Metabolome analysis revealed that a diet including RBPJ and SPI induced a greater than 1.5-fold change in the levels of 20 muscle atrophy-related metabolites. In particular, the level of S-adenosylmethionine, which concerned with energy metabolism and lifespan, showed a strong positive correlation with the muscle atrophy marker. These findings suggest that a diet including RBPJ and soy protein suppress gene expressions related with muscle atrophy. Further research in humans is needed to confirm whether a combination of RBPJ and SPI can indeed prevent muscle atrophy.

Untargeted Metabolomics Reveals the Effect of Selective Breeding on the Quality of Chicken Meat

“…Turinsky et al found that dissimilar concentrations of several free amino acids were identified in different types of myofibers; furthermore, increased concentrations of leucine and glutamic acid and a reduced level of glutamine and glycine were observed in denervation atrophied muscles [ 46 ]. Some studies proved that the concentration of glutathione declined in atrophic muscles due to reactive oxygen species, although Tachibana et al claimed that glutathione was highly detected in the denervation-induced muscle atrophy model; however, they speculated that the result was attributed to the brief duration of denervation [ 47 , 48 , 49 ]. Zhang et al found that glycerophospholipid metabolism and glutathione metabolism were significantly changed in breast muscle between slow-growth and fast-growth chickens, which were considered important functions in meat flavor [ 50 ].…”

Natural Compounds Attenuate Denervation-Induced Skeletal Muscle Atrophy

“…A mixed diet of soy protein and whey protein showed a strong inhibitory effect on denervation-induced skeletal muscle atrophy [ 143 ]. In addition, it has been reported that soy protein isolate and red bell pepper juice suppressed skeletal muscle atrophy in denervated mice [ 144 ]. Whey protein is known to stimulate muscle protein synthesis via mTOR signaling in humans [ 145 ].…”