초록
Male reproductive function seems to have deteriorated considerably in the past 4 to 5 decades. It was observed a significant decline in mean sperm counts from $113{\times}10^6/ml$ in 1940 to $66{\times}10^6/ml$ in 1990; a fall of $0.94{\times}10^6/ml/year$. We reported that Yacon tuber extracts have spermatogenic effects in rat. In the present study, we tested the spermatogenic effect of Yacon tuber extracts in healthy male volunteers. Subjects were assigned randomly to the control group and the Yacon ethanol extracts administered group (each 12 subjects). And, placebo or Yacon tuber extracts (100 ml) were administered two times daily, by oral for 3 months. Sperm numbers, biochemical parameters and hormone levels were recorded before starting administration, then every month. The Yacon tuber extracts administered group showed significant time dependant increases in according to administration period. Especially, the numbers of sperm increased by 54% after 3 months of administration. And, in Yacon tuber extracts administered group, testosterone and estradiol level were significantly higher than placebo group. On the other hands, Yacon tuber extracts didn't show any toxicity in glucose and lipid metabolism and liver and kidney function. The results of the present study suggest that Yacon tuber extract is a possible therapeutic for the treatment of sperm deficiency.
