n-3 polyunsaturated fatty acids regulate chemerin in cultured adipocytes: role of GPR120 and derived lipid mediators
Chemerin is a pro-inflammatory adipokine that is increased in obesity and associated with obesity-related comorbidities. The aim of this study was to investigate the effects of omega-3 polyunsaturated fatty acids, eicosapentaenoic and docosahexaenoic acids (EPA and DHA), on basal and tumor necrosis factor-alpha (TNF-alpha)-induced chemerin production in 3T3-L1 and human subcutaneous cultured adipocytes. The potential involvement of G protein-coupled receptor 120 (GPR120), as well as the actions of DHA-derived specialized proresolving lipid mediators (SPMs), resolvin D1 and D2 (RvD1 and RvD2) and maresin 1 (MaR1), were also evaluated. DHA significantly lowered both basal and TNF-alpha-stimulated chemerin production in 3T3-L1 and human adipocytes. EPA did not modify basal chemerin production, while it attenuated the induction of chemerin by TNF-alpha. Silencing of GPR120 using siRNA blocked the ability of DHA and EPA to reduce TNF-alpha-induced chemerin secretion. Interestingly, treatment with the DHA-derived SPMs RvD1, RvD2 and MaR1 also reversed the stimulatory effect of TNF-alpha on chemerin production in human adipocytes.