Besides the inhibition of HDACs, SCFAs are also known to exert their functions through G protein-coupled receptor (GPCR)-induced signaling.57 SCFAs mostly interact with GPR41 and GPR43.57,58 We examined the levels of GPR41, GPR43 and HDAC3 in RA-FLSs. This evidence concerns the gene FFAR3 and rheumatoid arthritis.