2008 年 54 巻 4 号 p. 286-290
Background: CoQ10 has come to be widely used as a dietary supplement, and daily intake of it has increased in recent years. CoQ10 is produced in all living organisms and is an essential coenzyme for energy synthesis in the mitochondria and an important scavenger of reactive oxygen species. Objective: This is a randomized, double-blind, placebo-controlled experiment to examine the acute effects of a single dose of CoQ10 on the autonomic nervous system (ANS) by using power spectral analysis of HRV and energy metabolism at rest and during low intensity exercise in healthy subjects. Eleven nonsmoking healthy male students (age: 26±1 y) volunteered to participate in this experiment. CM5 lead ECG and gas exchange parameters were recorded 5 min before, and 30 min and 60 min after the oral administration of CoQ10 or a placebo. Following this, the subjects exercised using a stationary cycle ergometer for 10 min at 60 rpm with an intensity of 30% of heart rate reserve. During the exercise, the ECG and gas exchange parameters were recorded continuously. Results: There were no significant differences in heart rate between the CoQ10 and placebo trials at rest or during exercise. With regard to the integrated values of the spectrum, there were no significant differences in the HF power representing parasympathetic activity or LF power representing both sympathetic and parasympathetic nervous activities between the trials at any timepoint. However, during the exercise, HF power and LF power in the CoQ10 trial showed a tendency to increase compared with the placebo trial (p<0.1). Total power representing the over-all ANS activity was significantly increased in the CoQ10 trial during exercise, which implied that autonomic nervous activity was augmented by CoQ10 (p<0.05). CoQ10 also induced enhanced lipid oxidation as shown by the significantly lower respiratory gas exchange ratio (R) and increased fat oxidation during exercise. The results shed some light upon the relationship between the autonomic nervous activity and energy metabolism. Conclusion: These results suggested that CoQ10 may increase fat oxidation with augmented autonomic nervous activity during low intensity exercise.