薬理と治療

Abstract

Objectives　Investigate the effects of Maca（Lepidium meyenii）extract-containing diet（ME diet）intake on male sexual dysfunction, particularly erectile dysfunction （ED）and other related health conditions（e.g. hormonal and mood status）. For this purpose, ME diet was administered to middle-aged and older men affected by medium to moderate ED and its results were measured. Methods　A randomized, double-blind, placebo-controlled clinical trial was conducted on 32 subjects, who received either tablet-form ME diet（n＝16）containing 1200 mg of prepared Maca extract powder or placebo（n＝16）for 8 weeks. ME diet effects on free-testosterone and dehydroepiandrosterone sulfate（DHEA︱S）levels on blood were measured. For measuring erectile and other sexual functions, International Index of Erectile Function（IIEF）and Global Assessment Question（GAQ）tests were applied. Mood status was measured applying the Japanese version of the POMS Short Form（POMS-S）. Measurements above were performed at baseline, week 4 and 8 or only at baseline and week 8. Results　The analysis was performed on 14 subjects on ME group and 15 subjects on placebo group who finished the test. The mean IIEF EF domain score for the ME group increased during the 8-week intervention period and showed a significant difference in Δ-value at week 4（P＝0.029）in comparison with placebo group values. There was a significant 9.1％ improvement in the overall IIEF score for the ME group compared with 0.6％ for the placebo group at week 4（P＜0.05）. The ME diet significantly increased serum concentration of DHEA-S（P＜0.01） without substantial effects on free testosterone concentration. An improvement on mood status was also confirmed by POMS-S test results. No ME diet-related adverse events were reported. Conclusion　The supplementation with ME diet may be beneficial for improving ED and other sexual dysfunctions, increasing serum concentration, as well as for improving male hormone function and mood status.