STRESS-INDUCED HORMONAL INDICES OF REPRODUCTIVE FUNCTION IN HEALTHY GIRLS WITH A DIFFERENT BODY MASS INDEX

Abstract

Aim. The article deals with the study of the dynamics of gonadotropins, sex steroids, leptin and ghrelin in healthy girls with a different body mass index for the assessment of reproductive function under stress conditions. Materials and methods. Based on anthropometric data, we formed three groups of girls with a different body mass index (BMI): the first group consists of girls with BMI less than 18.5 kg/m2 which corresponds with body mass deficiency (BMD); the second group – with BMI from 18.5 to 24.9 kg/m2 which corresponds with standard body mass (SBM); the third group – with BMI more than 30 kg/m2 which corresponds with Class I obesity (OCI). We determined hormone concentration in blood sample using the enzyme-linked immunosorbent assay in the conditions of daily study routine (background) and exams (emotional stress model). Results. We assessed stress-induced shifts in the cyclic activity of the hypothalamicpituitary-ovarian link of the endocrine system, as well as the contribution of energy homeostasis to adaptation of the reproductive system. Stress-induced reactions in the dynamics of hypothalamic response are especially significant for girls with body mass deficiency and Class I obesity. In girls with body mass deficiency, this level of emotional stress stimulates the reproductive system, in particular, by the positive dynamics of luteinizing hormone release. In girls with standard body mass, such responses are less pronounced. Class I obesity decreases the stress-protective activity of prolactin as its content changes significantly under these conditions. Conclusion. The stress-induced dynamics of leptin depends on the body mass index: in girls with body mass deficiency, the dynamics was positive (p &< 0.05); in girls with standard body mass, such dynamics decreased; in girls with Class I obesity, the response was minimal because of the development of leptin resistance. In all the groups examined, we registered the positive dynamics of ghrelin determined by its participation in the storage of plastic and energy resources during energy homeostasis under stress conditions.