Effects of ACTH-Pro-Gly-Pro Peptide on the Levels of Pro- and Anti-Inflammatory Cytokines in Wistar Rats under Conditions of Chronic Restraint Stress.

We evaluated the effect of ACTH-Pro-Gly-Pro (ACTH-PGP) peptide on the serum levels of pro- and anti-inflammatory cytokines in experimental animals under conditions of chronic restraint stress. Stress exposure over 2 weeks led to an increase in the levels of IL-1β, IL-6, and IFNγ in rats. Daily intraperitoneal injection of ACTH-PGP in a dose of 5 μg/kg before stress exposure significantly decreased the levels of IL-6 and IFNγ by 4.8 and 49.3% respectively. Administration of the peptide in a dose of 50 μg/kg decreased the levels of IL-1β and IFNγ by 51.2 and 39.7%, respectively. However, no changes in the cytokine levels were observed after injection of the peptide in a dose of 500 μg/kg. Thus, ACTH-PGP administered in doses of 5 and 50 μg/kg prevented the stress-induced changes in the levels of pro- and inflammatory cytokines.