AGE-DEPENDENT EFFECTS OF OXYTOCIN ON BODY WEIGHT REGULATION DURING CHRONIC CORTICOSTERONE EXPOSURE

Chronic stress activates the hypothalamic-pituitary-adrenal (HPA) axis, resulting in sustained elevations of corticosterone levels. Oxytocin is critical for metabolic control. This study aimed to investigate the age-dependent effects of oxytocin on body weight regulation in male rats under chronic corticosterone exposure. The administration paradigms included early childhood (PN10–40), mid-adolescence (PN10–60), and late adolescence (PN10–90), with corticosterone administered at a dose of 20 mg/kg daily to model chronic HPA axis hyperactivation. Following this treatment, subsets of animals received oxytocin at a dose of 0.1 mg/kg/day for 10 consecutive days via intraperitoneal injection. Body weight was measured at PN100, and data were analyzed using two-way ANOVA followed by Tukey’s post hoc test.Results indicated that short-term corticosterone exposure (PN10–40) did not significantly alter body weight compared to controls. However, prolonged exposure resulted in substantial weight gain, with increases of 12.5% in the PN10–60 group and 31.6% in the PN10–90 group. Chronic oxytocin administration demonstrated a clear age-dependent corrective effect. During mid-adolescence (PN10–60), oxytocin significantly reduced corticosterone-induced weight gain (p < 0.05), correlating with decreased hyperphagia and visceral adiposity. In the late adolescence group (PN10–90), oxytocin partially alleviated metabolic disturbances and visceral fat accumulation, though it did not fully normalize body weight.In conclusion, oxytocin plays a crucial role in regulating energy balance, with its efficacy diminishing in later developmental stages. These findings highlight the importance of developmental timing in metabolic interventions targeting obesity related to chronic stress.
Supported by Shota Rustaveli National Science Foundation FR-24-401