Formononetin Mediates α7nAChR to Inhibit Macrophage Polarization and Ameliorate Atherosclerotic Plaque.

ObjectiveTo explore the molecular mechanism of α7 nicotinic acetylcholine receptor (α7nAChR) mediated by Formononetin (FMN) in inhibiting macrophage inflammatory polarization and stabilizing atherosclerotic plaque.MethodsSiRNA α7nAChR was transfected into THP-1-induced M0 cells and treated with FMN. Oil Red O staining was used to evaluate macrophage lipid deposition. RT-qPCR was used to detect α7nAChR, COX-2, IL-1β, IL-6, HO-1, and SHIP1 expression in M1 and M2 macrophages. Western blot was used to detect α7nAChR, iNOS, CD206, CD68, p-JAK2, and p-STAT3 protein expression in M1 and M2 macrophages.ResultsCompared with the control group, FMN-mediated α7nAChR reduced lipid deposition in M1 and M2 macrophages. RT-qPCR results showed that FMN intervention significantly downregulated COX-2 and IL-1β expression in M1 (P < 0.05). α7nAChR expression significantly reduced COX-2, IL-6, and IL-1β expression in M2 (P < 0.05) and significantly increased HO-1 and SHIP1 expression (P < 0.05). FMN-mediated α7nAChR significantly decreased the expression of iNOS, CD68, p-JAK2, and p-STAT3 in M1 and M2 macrophages and significantly increased the expression of CD206 protein by Western blot (P < 0.05).DiscussionThis study, for the first time, elucidated the mechanism of FMN regulating macrophage polarization through the α7nAChR/JAK2/STAT3 axis, providing new experimental evidence for the role of the cholinergic anti-inflammatory pathway in cardiovascular diseases. However, there are some limitations, such as the limited applicability of the THP-1 cell line, the need to strengthen the dose correlation study, the bioavailability and solubility limiting clinical translation, and the lack of human toxicological data.ConclusionFMN effectively modulates macrophage polarization through inhibition of the JAK/STAT signaling pathway while promoting α7nAChR expression.