MitoROS could activate the NF-κB pathway, p38/MAPK (mitogen-activated protein kinase) pathway, and JNK1/2 (c-Jun N-terminal kinases 1/2) pathway directly or indirectly and form positive feedback with TNF-α to exacerbate the progression of RA (26). This evidence concerns the gene MAPK8 and rheumatoid arthritis.