Effect of dynamic high-pressure treated chicken meat on skeletal muscle of sarcopenia model mice

Background and objectives: The water pressure in running water is called dynamic high-pressure (DHP), and it is characterized by the physical forces of shear, impact, and cavitation that act with the pressure. DHP treatment of protein is expected to modify the structure of protein and improve absorption. Exercise and high-quality protein intake are necessary to prevent sarcopenia, which has become a nutritional problem in an aging society in recent years. However, most of the protein supplements on the market are powders obtained by enzymatically treating milk and soybeans. In this study, chickens were DHP-treated with a high-pressure homogenizer and tested in vitro for improved absorption of denatured protein. Furthermore, the effects of Ezm+DHP intake the increase in skeletal muscle mass was investigated in sarcopenia model animals. Methods: Chicken breast strips were treated with DHP (150MPa, 15passes: DHP), enzymatic (protease, 30min: Ezm), and combination of them (Ezm+DHP). Then they were freeze-dried and pulverized. Protein denaturation was evaluated by the protein solubility test and quantification of amino groups by OPA method. Improvement digestibility of these samples were evaluated by artificial digestive test. SAMP8, which develops sarcopenia due to accelerated aging, were given Control diet containing CTL(n=10) or a test diet containing Ezm+DHP(n=10), and treadmill training was performed for 5 months. Results: The results of the protein solubility test, DHP and Ezm+DHP decreased hydrogen bonds and increased hydrophobic interactions. The quantitative of amino groups increased significantly in the order of DHP, Ezm, and Ezm+DHP relative to CTL. This result suggests that the lowest molecular weight is achieved in the combined treatment of Ezm+DHP, rather than in the treatment of Ezm or DHP alone. Ezm+DHP diet group was shown to have significantly increased the extensor digitorum longus muscle (EDL) compared to that of the CTL diet group. Conclusions: These results indicate that intake of meat reduced in molecular weignht by Ezm+DHP treatment improved protein absorption, and amino acid or prptides retained in the body were used for skeletal muscle synthesis through endurance exercise. Ezm+DHP-treated meat could become a new protein material in the future.