Effects of Cordyceps militaris fermentation products on reproductive development in juvenile male mice

Cordyceps militaris (CM) is a popular medicinal fungus; however, few studies have focused on its impact on the male reproductive system. We evaluated the effects of CM fermentation products on the reproductive development of juvenile male (JM) mice. Mice were divided into four experimental groups, each fed 5% CM products (weight per weight (w/w) in normal diet): extracellular polysaccharides (EPS), fermentation broth (FB), mycelia (MY), and whole fermentation products (FB plus MY, FBMY) for 28 days, while mice in the control group (CT) were fed a normal diet. Basic body parameters, testicular structure, sperm parameters, and sex hormones concentrations were analyzed. Compared to the CT group, mice in the EPS, MY, and FBMY groups showed a significantly increased mean seminiferous tubule area (p < 0.05), mice in the FB and MY groups had significantly higher sperm concentrations (p < 0.05), and mice in the EPS, FB, and FBMY groups showed significantly increased ratios of motile sperm (p < 0.05). Meanwhile, EPS significantly promoted the ability of JM mice to synthesize testosterone (p < 0.05). Furthermore, all CM products significantly increased the food intake of JM mice (p < 0.05) but did not significantly change their water intake and body weight gain (p > 0.05). In conclusion, CM products, especially EPS, exhibit strong androgen-like activities that can promote male reproductive development.