The aim of our research is to examine the effects of selected plant extracts, phytoestrogens (genistein, daidzein), steroid (estradiol, progesterone, testosterone, dexamethasone) and peptide hormones (somatostatin, calcitonin, ghrelin) on neuroendocrine and mineral homeostases in rats. Herbal and nature alternatives to hormone replacement therapy are intensively advertised for maintenance of hormone balance, prevention of cardiovascular problems, atherosclerosis and osteoporosis in both sexes. Assessments of effects of these substances on: (i) hypothalamo-pituitary -adrenal, -somatotropic, -thyroid and -gonadal axes; (ii) neuroendocrine C-cells, bones, parathyroid glands and kidneys; and (iii) cellular mechanics are important for evaluation of their health risks / benefits and potential use in treatment of cancer, cardiovascular and other diseases. The examinations are carried out in rats of different age (adult, middle and old age) and sex, with special emphasis on models of andropause and menopause. In vitro studies of cellular mechanics are performed using erythrocytes or prostate cancer cells. Glucocorticoids are used in human pregnancies at risk of preterm delivery because they reduce neonatal mortality and morbidity. However, this treatment enhances maturational processes and provokes permanent changes in physiological systems. Thus, short-term beneficial effects of prenatal glucocorticoids are, at the same time, the ones that increase the long-term risks of dysregulation of the metabolic function and endocrine axes, including stress response, growth and reproduction. Effects of prenatal glucocorticoid overexposure are examined in rats from their fetal period of life till adulthood.