Effect of Heat Stress, Zinc, and Cholecalciferol (Vitamin D۳) on the Cortisol and Cytokine-mediated Responses of Laboratory Rats in Kirkuk City, Iraq

Background: Both major and minor stressful events can have direct adverse effects on a variety of immunological mechanisms. Experimental data have shown that any improvement in vitamin D۳ status can result in a major change in the expression of genes that affect biological disorders linked to vitamin D۳ deficiency, such as cardiovascular diseases, autoimmune disorders, and cancer. Objectives: This study aimed to measure the effects of heat stress and zinc and vitamin D۳ supplementation on serum cortisol, interleuken-۶ (IL-۶), and interferon-gamma (INF-g) levels in male rats.Methods: Five equal groups of rats (n=۱۰) were assigned to different treatment groups as follows: control, heat stress(exposed to ۳۵ °C for ۲ hours/day), zinc (۵۰ mg/kg diet), vitamin D۳ (۵۰ μg/kg of diet), and combined intervention (heat stress plus zinc and vitamin D۳ supplementation). The treatment regimen lasted for four weeks. Results: Statistically significant differences were reported for all comparisons of cortisol levels between the five treatment groups (P≤۰.۰۰۱) except between the control and vitamin D groups and between heat stress and zinc groups (P>۰.۰۵). Regarding the Il-۶ levels, a statistically significant difference observed between all groups (P≤۰.۰۰۱) except between the control and zinc groups (P>۰.۰۵). Finally, statistically significant differences were also noticed regarding the IFN-g levels between all study groups, except in the heat stress and zinc groups compared to the control group (P>۰.۰۵). Conclusion: Heat stress and zinc and vitamin D۳ supplementation can significantly affect the levels of stress-related hormones and the expression of immune response–stimulating cytokines. These findings suggest that physiological and nutritional factors are closely interlinked in modulating immune homeostasis.

کلیدواژه ها:

heat stress ، Interleuken-۶ (IL-۶) ، Interferon-gamma (INF-g) ، Vitamin D۳ ، Zinc