PPARA and rheumatoid arthritis: According to the KEGG analysis, We can also learn that DEGs are mainly enriched in the following pathways, pathways of immunological and inflammation-related diseases (AGE-RAGE signaling pathway in diabetic complications, fluid shear stress, and atherosclerosis, rheumatoid arthritis), there are also some immune-related pathways (IL-17 signaling pathway, TNF signal channel, the TGF signaling pathway, PPAR signaling pathway, and other pathways)(Figure 5).