Sesame Lignans Prevent Age—related Decline in Spontaneous Activity by Modulating Muscle Mass

Background　Decreased physical activity with aging is a significant risk factor for age-related diseases and requires nursing care. Objective　Sesame lignans（SE, sesamin and episesamin）exert anti-oxidative and anti-inflammatory effects. Here, we evaluated the effect of SE on decline in spontaneous activity in aging rats. Methods　Fourteen-month-old Sprague-Dawley rats were fed a diet with or without 0.1％ SE for 8 months. Spontaneous activity was measured by using an accelerometer at 14, 17, and 22 months of age before or after SE administration. Five-month-old rats were included as a young control group. Results　Spontaneous activity decreased with aging; SE significantly prevented the decrease. SE reduced the decrease in fast-twitch muscle mass, but not slow-twitch muscle, with aging and also suppressed increased muscle RING finger 1（Murf1）gene expression in muscle and interleukin（IL）-6 in plasma. Conclusion　Consecutive intake of SE modulated muscle mass through inhibition of Murf1 expression due to anti-inflammatory effects, resulting in preventing decreased spontaneous activity with aging.