薬理と治療

Abstract

Objectives According to an epidemiological survey by the Fatigue Study Group of Ministry of Health, Labour and Welfare in 1999, about 60%(47.2 million)of Japanese working population complained of fatigue, moreover according to a survey in Aichi Prefecture by Health Labour Sciences Research in 2012, 51% of the population was aware of fatigue. These results show that the social environment related to fatigue has not changed in the last 10 years. However, there have been no established recommendations for fatigue, and few antifatigue medicines or foods have been developed. Oxidative stress is known to cause fatigue, so antioxidants are potential candidates for anti-fatigue agents. Imidazole dipeptides, which are abundant in whale meat, are reported to have strong antioxidative effects. We investigated the effect of whale meat extract on fatigue induced by physical load and by daily activities in humans. Methods In this double-blind, placebo-controlled, crossover trial, 12 healthy volunteers were randomized to oral administration of whale meat extract(400mg of imidazole dipeptides)or placebo for 29 days. The subjects took 12 capsules of whale meat extract or placebo twice a day for 29 days. As a fatigue-inducing physical load, the subjects performed workload trials on a cycle ergometer at fixed workloads for 4 hours and then rested for 4hours. We evaluated subjective fatigue sensation using the visual analogue scale and autonomic nervous system by accelerated plethysmography. Moreover we evaluated fatigue induced by daily activities using the Chalder fatigue scale in the 4-week administration period. Results The administration of oral whale meat extract administration attenuated fatigue sensation and modulated sympathetic dominance induced by physical load, and decreased the total score of Chalder fatigue scale in the 4th week. Conclusions These results show that whale meat extract has an effect on attenuating fatigue induced by physical load and daily activities, so it is a promising candidate for antifatigue food.