Crosstalk between ferroptosis and NLRP3, a possible therapeutic target in experimentally-induced rheumatoid arthritis: role of P2Y12R inhibition in modulating P53/SLC7A11/ALOX15 signaling.

Ferroptosis is critical in progressing and exacerbating rheumatoid arthritis (RA) and other inflammatory joint diseases. Inhibition of the P2Y12 receptors reduced iron overload in macrophages displaying an anti-inflammatory response. Herein, the ameliorative effect of ticagrelor, a reversible P2Y12 inhibitor, against adjuvant-induced arthritis (AIA) in rats was investigated, with a special emphasis on the possible modulation of some inflammatory signals linked to ferroptosis. Particularly, correlation analyses were conducted between nod-like receptor protein 3 (NLRP3) and all assessed parameters. Four groups of rats were assigned: Control group, AIA group (0.1 ml intradermal injection of complete Freund's adjuvant), Ticagrelor group (30 mg/kg, p.o.), and Ticagrelor + AIA group. Ticagrelor exhibited an anti-arthritic effect, evidenced by significant improvements in both macroscopic and histopathological alterations. It effectively inhibited ferroptosis, indicated by a marked upregulation of the ferroptotic inhibitors, solute carrier family 7 member 11 (SLC7A11), glutathione peroxidase 4 (GPX4) and ferritin heavy chain 1 (FTH1) to reach 9.80, 2.20, and 8.49-folds (p < 0.0001), along with a notable reduction in the ferroptotic promoters, P53, acyl-CoA synthetase long-chain family member 4 (ACSL4) and arachidonic acid 15-lipoxygenase-1 (ALOX15) by 89.46%, 41.45% and 49.85% (p < 0.0001). It reduced TNF-α and various chemokines (RANTES, MIP-1α, eotaxin-3) to suppress matrix metalloproteinases expression. Furthermore, ticagrelor decreased NLRP3 expression by 48.63% (p < 0.0001) to pinpoint its anti-inflammatory effect. Overall, amending the P53/SLC7A11/ALOX15 axis by ticagrelor mediated its anti-inflammatory and anti-ferroptotic effects. These findings provide preliminary experimental evidences for further investigating the potential impacts of ticagrelor as a treatment for RA.