Melanocortin-derived tripeptide KPV has anti-inflammatory potential in murine models of inflammatory bowel disease

This study evaluated the therapeutic potential of the tripeptide KPV (Lys-Pro-Val) in two well-established murine models of inflammatory bowel disease (IBD): DSS-induced colitis (acute model) and T cell transfer colitis (chronic model mediated by adaptive immunity). The investigation also explored the role of melanocortin 1 receptor (MC1R) in the mechanism of action.

Animals treated with KPV showed significantly faster recovery than controls, with greater weight gain and less weight loss during acute disease phases. Histopathological analysis revealed marked reduction of inflammatory infiltrates in the colonic mucosa, with less destruction of intestinal crypt architecture.

An intriguing and mechanistically relevant observation was that the anti-inflammatory effects of KPV were only partially dependent on MC1R signaling. Experiments with mice carrying MC1R gene mutations showed that, although efficacy was attenuated, KPV still exerted residual anti-inflammatory activity. This suggests the existence of alternative signaling pathways.

The authors concluded that KPV has significant therapeutic potential for IBD, with the advantage of being a small peptide (only 3 amino acids), easily synthesizable, and well tolerated. The activation of multiple anti-inflammatory pathways may represent an advantage over single-target molecular therapies.