IL17A and rheumatoid arthritis: The KEGG enrichment results indicated that the up-regulated DEGs were primarily concentrated in pathways related to amino acid metabolism, carbohydrate metabolism such as tryptophan metabolism, arginine biosynthesis, glycolysis/gluconeogenesis, etc. (Figure 4C), whereas the down-regulated DEGs were mainly abundant in pathways related to signal molecule interactions, immune diseases, signal transduction, such as significantly associated rheumatoid arthritis, the IL-17 signaling pathway, and the PI3K-Akt signaling pathway, among others.