Endocrine Abstracts

JOINT1735

During last decades, diets rich in vegetables and seeds have grown in popularity. However, these so-called healthy diets can contain phytoestrogens which are potential endocrine disruptors. As hormonal fluctuations play a crucial role in genital tract differentiation, the fetal development represents a major period of vulnerability to endocrine disruptors. Sesamol, a phytoestrogen derived from sesame seeds, has a similar chemical structure to natural estrogen, enabling it to bind to estrogen receptors. By crossing the placental barrier, sesamol could disturb the hormonal balance of the foetus and interfere with the metabolism and the development of reproductive organs. The aim of this study is to investigate the effects of prenatal exposure to sesamol on the folliculogenesis and metabolism in F1 female offspring rats. From the 14th to the 19th day of gestation, pregnant female Sprague-Dawley rats were force-fed with different doses of sesamol (30 or 100 mg/kg/day). On the 4th day of post-natal life, female offspring rats were sacrificed to study reproductive (ovaries) and metabolic (liver, pancreas and kidneys) organs by histological analysis. Morphometric analysis of ovaries revealed that in utero exposure to sesamol enhanced the rate of apoptosis in oocytes present in primordial follicles, resulting in a 2-fold increase in the number of atretic follicles. However, the treatment does not affect the relative proportion of primordial, primary and secondary follicles, and has no impact on the proliferation rate of follicular and thecal cells assessed by BrdU labeling. Concerning the study of metabolism, no major morphological alteration was observed in the kidneys of animals exposed to sesamol. However, the morphometric assessment of cell proliferation rate by anti-BrdU immunohistochemistry showed a significant decrease in the number of S-phase cells in the renal inner medulla. Moreover, a significant decrease in body weight was observed in animals exposed in utero to sesamol. Further analysis of the pancreas (anti-insulin and anti-glucagon IHC) and liver (anti-BrdU IHC, lipids accumulation) are in progress to fully understand this decrease in body weight. In conclusion, the present results indicate that sesamol seems to have a negative impact on the development of female gonads, which could lead to fertility dysfunctions in adulthood. We plan to study in greater detail the mechanisms by which sesamol increases follicular atresia and its impact on general metabolism.