Blockade of Proteinase-Activated Receptor 2 (Par2) Attenuates Neuroinflammation in Experimental Autoimmune Encephalomyelitis Publisher Pubmed

Summary: PAR2 blocker P2pal-18S eased EAE, reduced demyelination/infiltration—PAR2 target for MS therapy. #MultipleSclerosis #Neuroinflammation

Eftekhari R^{1, 2, 3, 7, 8} ; Ewanchuk BW^{4, 5, 7} ; Rawji KS^{3, 7} ; Yates RM^{4, 5, 7} ; Noorbakhsh F^{7, 8} ; Kuipers HF^{3, 6, 7} ; Hollenberg MD^{1, 2, 7}
Source: Journal of Pharmacology and Experimental Therapeutics Published:2024

Abstract

Proteinase-activated receptor-2 (PAR2), which modulates inflammatory responses, is elevated in the central nervous system in multiple sclerosis (MS) and in its murine model, experimental autoimmune encephalomyelitis (EAE). In PAR2-null mice, disease severity of EAE is markedly diminished. We therefore tested whether inhibiting PAR2 activation in vivo might be a viable strategy for the treatment of MS. Using the EAE model, we show that a PAR2 antagonist, the pepducin palmitoyl-RSSAMDENSEKKRKSAIK-amide (P2pal-18S), attenuates EAE progression by affecting immune cell function. P2pal-18S treatment markedly diminishes disease severity and reduces demyelination, as well as the infiltration of T-cells and macrophages into the central nervous system. Moreover, P2pal-18S decreases granulocyte-macrophage colony-stimulating factor (GM-CSF) production and T-cell activation in cultured splenocytes and prevents macrophage polarization in vitro. We conclude that PAR2 plays a key role in regulating neuroinflammation in EAE and that PAR2 antagonists represent promising therapeutic agents for treating MS and other neuroinflammatory diseases. Copyright © 2023 by The American Society for Pharmacology and Experimental Therapeutics.