Pogostone Suppresses Microglial <scp>NLRP3</scp> Inflammasome Activation‐Promoted Remyelination Through <scp>RXRγ</scp> Regulation of Mitophagy

Multiple sclerosis (MS) is a chronic autoimmune disease involving central nervous system nerve demyelination accompanied by intense neuroinflammation. Pogostone (PO), a major component of Pogostemon cablin, has anti-inflammatory, immunosuppressive, and antioxidant properties. In this study, we characterized the therapeutic potential of PO in remyelination and elucidated the underlying mechanisms. In cuprizon (CPZ)-induced demyelinating mice, rotarod test, RNA sequence, molecular docking, immunofluorescence, and western blotting were used to analyze the targets and signaling pathways involved in PO treatment. Meanwhile, the changes of mitophagy and NLRP3 inflammasome were detected after further treatment with RXRγ antagonist UVI3003. In lipopolysaccharide (LPS)-induced BV2 microglia, after interference with RXRγ or blockade of mitophagy by 3-methyladenine (3-MA), the effects of PO on mtROS, mitochondrial membrane potential (MMP), NLRP3 inflammasome and mitophagy were measured by flow cytometry, immunofluorescence and western blotting. PO treatment effectively promoted remyelination in the CPZ model, and this effect was achieved by activating RXRγ. Meanwhile, PO suppressed microglial NLRP3 inflammasome activation through enhancement of PINK1/Parkin-mediated mitophagy, but this change was reversed by the RXRγ antagonist UVI3003. In LPS-induced BV2 microglia, interference with RXRγ reversed the inhibitory effect of PO on mtROS production, MMP decline, and NLRP3 activation. In addition, blockade of mitophagy by 3-MA reversed the inhibitory effects of PO on mtROS production and NLRP3 inflammasome activity. The present study demonstrated that PO suppresses microglial NLRP3 inflammasome activation-promoted remyelination via RXRγ regulation of mitophagy, which suggests PO as a promising drug candidate for the treatment of MS.