EFFECTS OF METABOLIC AND NONMETABOLIC STRESSORS ON THE EXPRESSION AND ACTION OF NEUROENDOCRINE REGULATORS OF ENERGY HOMEOSTASIS

In times of rising prevalence of eating disorders, the role of peripheral hormones and metabolites in energy homeostasis regulation is fully recognized. While these disorders induce stress response, appetite is also influenced by various stressors. Therefore we will examine distinct and combined effects of metabolic (fasting, restrictive caloric intake, prolonged overfeeding with fat enriched foods) and non-metabolic stressors (immobilization, aggregation, restraint, isolation, low and high ambient temperatures, chemical toxins) on neuroendocrine regulation of energy homeostasis. We shall measure the content of insulin, leptin, galanin and its GAL3 receptor, adiponectin, CRH, vasopressin and Fatso protein in hypothalamus; concentrations of adenopituitary hormones, leptin and Fatso in pituitary glands under the influence of these stressors. The metabolic status will be monitored by measuring blood levels of glucose, urea, free fatty acids, insulin and leptin, while stress hormone levels will help estimate hypothalamo-pituitary-adrenal axis function. We will determine monoamine content in the hypothalamus and study the mechanisms of their synthesis and degradation by quantifying mRNA levels for dopamine-ß-hidroxylase and catechol-O-methyl-transferase. Lastly, expression and activity of antioxidative protection enzymes will be investigated. Expanded understanding of the energy homeostasis of neuroendocrine regulation may change the approach to therapy for eating disorders.