MMK1 is an agonist of formyl peptide receptor 2 (FPR2), which was previously known as formyl peptide receptor-like 1 (FPRL1).1 MMK1 induces calcium flux in CHO cells expressing human FPR2 and Gα16 (EC50 = <2 nM) but not in CHO cells expressing Gα16 alone or in combination with FPR1 (EC50s = >10,000 nM for both). It induces chemotaxis of isolated human peripheral blood monocytes and neutrophils in a concentration-dependent manner.2 MMK1 (10 µM) increases production of the proinflammatory cytokines IL-1β and IL-6 in isolated human monocytes. Intracerebroventricular administration of MMK1 (100 pmol/mouse) increases the percentage of time spent in the open arms of the elevated plus maze in mice, indicating anxiolytic-like activity.3
1.Klein, C., Paul, J.I., SauvÉ, K., et al.Identification of surrogate agonists for the human FPRL-1 receptor by autocrine selection in yeastNat. Biotechnol.16(13)1334-1337(1998) 2.Hu, J.Y., Le, Y., Gong, W., et al.Synthetic peptide MMK-1 is a highly specific chemotactic agonist for leukocyte FPRL1J. Leukoc. Biol.70(1)155-161(2001) 3.Zhao, H., Sonada, S., Yoshikawa, A., et al.Rubimetide, humanin, and MMK1 exert anxiolytic-like activities via the formyl peptide receptor 2 in mice followed by the successive activation of DP1, A2A, and GABAA receptorsPeptides8316-20(2016)