Effects of Chronic Dietary Exposure to Genistein, a Phytoestrogen, During Various Stages of Development on Reproductive Hormones and Spermatogenesis in Rats

Abstract

Developmental, hormonal, and gametogenic parameters were evaluated in male progeny following chronic dietary exposure to the phytoestrogen genistein. Twenty pregnant rats were fed a diet containing genistein (50 microg/d) from d 17 of gestation, and 12 were fed a control diet without genistein. Four litters each of control and genistein-fed rats were euthanized on d 21. The remaining pups were weaned on d 21 and only male rats were used in this study. On d 21, eight litters of genistein-fed rats were placed on control diet (gestational and lactational exposure alone [GL-G]), and the remaining eight continued on genistein diet (lifelong exposure group [LL-G]). These rats were euthanized (four litters/group) on d 70 or 130 of life. Serum testosterone, which was slightly reduced in genistein-exposed rats on d 21, did not differ among treatment and control groups on d 70 and 130. Serum luteinizing hormone of genistein-exposed rats was reduced on d 21 and 130, but not on d 70. Serum follicle-stimulating hormone did not vary among groups at any age. Treatment-related effects of dietary genistein were not observed on the weights of the testes of 21-d-old rats. Except for a slight decrease in testis weight of GL-G rats at 130 d, no significant effect of dietary exposure was observed on the weight of the testes in any other group. However, epididymal weights were significantly reduced in both treated groups at d 130. Testicular sperm count (on d 70 as well as 130) also was not affected in GL-G or LL-G rats. We conclude that gestational plus lactational exposure to genistein and subsequent dietary exposure to genistein have no adverse effects on gametogenic function in male rats.

<b>Semen traits, testicular morphometry and histopathology of cadmium-exposed rabbit bucks administered methanolic extract of <i>Phoenix dactylifera</i> fruit

“…More so, report by Bahmanpour et al (2006) confirmed that Phoenix dactylifera have gonadotrophin-like effects which could be due to its steroidal components. The date phytochemicals genistein (Roberts, Veeramachaneni, Schlaff, & Awoniyi, 2000;Eustache et al, 2009), vitamin A (Bartlett, Weinbauer, & Nieschlag, 1989) and selenium (Jana et al, 2008) have all been reported to protect testicular functions against various stress and possess gonadotropic activity, and the presence of these compounds may have contributed to the observed ameliorating effects recorded here in.…”

Xenopus laevis is a potential alternative model animal species to study reproductive toxicity of phytoestrogens

“…Simultaneously, some authors reported that there are no significant effects of phytoestrogens in rodents (Roberts et al, 2000;Mitchell et al, 2001;Lamartiniere et al, 2002). One of the explanations for these inconsistent results is that commercial rodent diets all contain high and variable levels of abundant phytoestrogens, which could affect results of studies on reproductive toxicity of test phytoestrogens (Odum et al, 2001;Stroheker et al, 2003;Naciff et al, 2004;Thigpen et al, 2004).…”

Disruption of reproductive development in male rat offspring following gestational and lactational exposure to di-(2-ethylhexyl) phthalate and genistein

“…Although many studies have examined the effects of single EDC using in vitro or in vivo assays (Christiansen et al, 2010;Roberts et al, 2000), few studies have been conducted to examine the eff ects of mixtures of EDCs on mammalian reproductive development, especially for those EDCs that act via diff erent mechanisms. So as a result of growing concerns about mixture exposure in reality recently, research on EDC mixture exposure during pregnancy and lactation have became a focus in andrology and toxicology (Kortenkamp, 2008).…”