抄録
In an aging society, extending the healthy life expectancy of the elderly is an urgent issue. Since the healthy life expectancy is nothing less than maintaining physical function to live an independent life, there is a need to elucidate the mechanisms that increase muscle mass and strength. In the course of this research for functional analysis of bile acids, catabolic products of cholesterol, we have focused our research on the function of TGR5, a bile acid receptor. We sought to clarify the function of TGR5, especially in the skeletal muscle, by analysis of multiple species of genetically modified mice. As a result, TGR5 activation by bile acids in the skeletal muscle was found to lead to muscle hypertrophy and strengthening. Furthermore, we have established an evaluation system for the search of food ingredients that activate TGR5 instead of bile acids, and found that, in food ingredients, nomilin, a citrus limonoid, has a TGR5 agonist activity. In this review, new physiological functions of bile acids were discussed, relating to the possibility of maintaining skeletal muscle function by food ingredients.
