Effect of tea and herbal infusions on mammalian reproduction and fertility

Philosophiae Doctor - PhDCamellia sinensis (tea) and Aspalathus linearis (rooibos) may improve reproductive function owing to their antioxidant properties. To test this hypothesis, male and female rats were given 2% and 5% green tea (Gt), black tea (Bt), unfermented rooibos (Ur) or fermented rooibos (Fr) as sole source of drinking for 52 and 21 days respectively. Control rats received tap water. In addition, TM3 Leydig cells were exposed to 0.025, 0.05, 0.1 and 0.5 % aqueous extracts of green tea, black tea, unfermented and fermented rooibos for 24h. In vitro analysis of tea and the herbal infusion revealed the phenolic property and antioxidant capacity (FRAP) in the order Gt > Bt > Ur > Fr. Camellia sinensis and Aspalathus linearis revealed no significant effect on serum antioxidant capacity (p > 0.05) and lipid peroxidation (MDA) in the kidney or liver in both male and female rats and in the testes of the male rats (p > 0.05). In addition, the antioxidant levels were maintained in the testes, liver and kidneys in both the male and female rats. In the male rats, no significant alterations were observed in body weight gain, liver and reproductive organs weight, and serum testosterone (p > 0.05). Only, 5% green tea significantly increased testosterone level (p 0.05). Sperm viability was enhanced in all treatment groups (p 0.05). In addition, green tea, black tea and fermented rooibos enhanced acrosome reaction (p 0.05) reflecting the significant increased kidney weight in the treatment groups at high concentrations. Liver markers, ALT and AST, decreased significantly in all treated groups (p 0.05). However, 5% fermented rooibos reduced the ovarian weight (p 0.05). Creatinine activity was enhanced significantly only by 5% fermented rooibos (p < 0.05). Liver markers, ALT and AST were reduced in most treated groups except in fermented rooibos where an increase was observed. In addition, histological sections revealed no obvious alteration in the ovaries, uteri, kidneys and liver of all treated female rats. Camellia sinensis and Aspalathus linearis significantly reduced the level of testosterone produced in TM3 Leydig cells under stimulated conditions in vitro (p< 0.05). Furthermore, both plants maintained the viability and morphology of the cells. However, at 0.5% of either plant extracts, a significant decrease in the viability (p < 0.05) and altered morphology of the TM3 Leydig cells was observed. In conclusion, Camellia sinensis and Aspalathus linearis significantly improved certain sperm function which might be attributed to their high level of antioxidant activity. However, the prolonged exposure of both plant extracts might result in subtle structural changes in the male reproductive system and impair kidney function. In addition, fermented rooibos at high concentration may also impair the functions of the liver. In vitro, both plants were shown to possess anti-androgenic property on TM3 Leydig cells. Furthermore, both Camellia sinensis and Aspalathus linearis may be classified as weak phytoestrogens due to the changes in the weight of the uterus and ovaries observed.South Afric