In peripheral blood leukocytes, the GPR43 mRNA expression was significantly reduced (0.05 ± 0.01 vs. 0.06 ± 0.01, P = 0.011) and the NLRP3 was remarkably increased (0.38 ± 0.25 vs. 0.23 ± 0.09, P = 0.007) in AF patients compared to the controls based on qRT-PCR analyses (Fig. 1A, C), consistent with the alterations of GPR43 and NLRP3 protein expression (Fig. 2A–C). Here, FFAR2 is linked to atrial fibrillation.