The effects of isoflavone-riched soybean flour, Zinc (Zn) and vitamin E on fertility of male rats as animal model

Abstract

The objectives of this research were to (1) evaluate the effects of isoflavone-riched soybean flour, zinc (Zn) and vitamin E on fertility of male rats, (2) evaluate the effects of isoflavone-riched soybean flour with different levels of isoflavone on fertility of male rats. Prior the in vivo experiment, isoflavone-riched soybean flour was defatted using n-hexane. Quantitative analysis of isoflavone on the defatted-soybean flour was conducted by HPLC, while antioxidant activity on the defatted-soybean flour was conducted by DPPH method. Total isoflavone on the defatted-soybean flour (TKI-RL) was considered as the basic concentration that used to calculate isoflavone dosages for the in vivo experiment. Male and female weaning Sprague Dawley rats (21 days old) were used as the animal model in the experiment. On the 1st stage of the experiment, the male rats were given basic diets containing isonitrogen and isocalories with 15% of dietary protein from casein. Thirty male Sprague Dawley weaning rats (21 days old) were divided into six groups and treated with isoflavone-riched soybean flour, Zn and vitamin E in different combination. Isoflavone-riched soybean flour (3mg/day) was given by oral administration, whereas Zn and vitamin E were mixed with the basic diet. The treatment was conducted for 2 month. On the other hand, thirty female Sprague Dawley rats were only given the basic diets containing 15% of dietary protein from casein to observe the fertility of male rats. After 2 months, both male and female rats were mixed (1:1). Vagina swabs on the female rats were taken every morning to evaluate the conception rate and to detect spermatozoa by Giemsa dyes. Once the spermatozoa detected on the female rats (the 1st day of pregnancy, D1), the male rats were sacrificed by dislocation of cervical bones (dislocasio cervicalis), then all the parameters were tested. On the day 15th of pregnancy, the female rats were sacrificed (D15), the conception rates and total fetus were counted.