The effects of select plant extracts, phytoestrogens, steroid and peptide hormones on the rat neuroendocrine system

This project will examine the effects of select plant extracts that contain phytoestrogens and of purified phytoestrogens genistein and daidzein on the neuroendocrine system of rats. Plant extracts and phytoestrogens are increasingly used to maintain hormone balance, prevent ageing-associated cardiovascular problems, atherosclerosis and osteoporosis in both sexes. The analogues of testosterone and estradiol, calcium, vitamin D and calcitonin are also used to treat andropausal, menopausal symptoms and osteoporosis. Prenatal treatment with dexamethasone causes a programming effect and permanently alters the neuroendocrine system. Ghrelin is a peptide that modulates function of adipose tissue. Each of these treatments can disrupt endocrine homeostasis at different levels. The data on the possible beneficial or harmful effects of these therapeutics are incomplete despite their wide use. We will examine the effects of the above treatments on the hypothalamic-pituitary-adrenal, -thyroid and -gonadal axes, C cells, parathyroid glands, bones and kidneys in male and female rats at different periods of life and nutritional status. The research will be carried out using immunohistochemical, morphometric, biochemical and molecular biological methods. The results will provide insight into the effects and mechanisms of the action of these bioactive substances on the neuroendocrine system in rats, on metabolism, growth, development and reproduction.