Alterations of Human Autonomic Nervous System Activity on Capsaicin Ingestion, and Variants of UCP1 and β₃-adrenergic Receptor Polymorphism

We investigated whether 1) capsaicin ingestion (100 ㎎) enhances autonomic nervous system (ANS) activities associated with thermogenic sympathetic activity as energy metabolic modulator, 2) UCP1 and β₃-AR variants of each subjects influence with ANS activity. Eight healthy males (24.7 ± 1.8 yr)volunteered for this study. The cardiac autonomic nervous activities evaluated by means of heart rate variability of power spectral analysis and energy metabolism were continuously measured during 5-min rest for total 90-min resting condition with placebo or capsaicin oral administration chosen at random. The results indicated that there were no significant differences in heart rate during rest between both trials. Autonomic nervous activity increased in capsaicin tablet trial, but the difference did not reach the statistical significance. Capsaicin, however, induced significantly lower respiratory gas exchange ratio at Test3 (CAP: 0.80 ± 0.02 vs. 0.85 ± 0.02), means ± SE, p＜0.05). In conclusion, it may be suggested the capsaicin consumption as a valuable supplement for the treatment of individual with hyperlipidemia and/or obesity by improving lipolysis. Further studies will also be considered genetic variants such as UCP1 and/or β₃-AR associated with obesity.