The expression of PGC-1β mRNA and protein in RA-FLS was significantly enhanced compared with OA controls (3.18 ± 1.72 versus 1.17 ± 0.74, P = 0.019; 0.33 ± 0.17 versus 0.11 ± 0.08, P = 0.014, respectively) (Figure 2B). This evidence concerns the gene PPARGC1B and rheumatoid arthritis.