GAPDH and rheumatoid arthritis: We found that a summarized transcription of glycolytic enzymes G6PD, HK3, PFKFB3, PFKFB2, ALDOA, PGM1, LDHA, PGAM1, ENO1, and GAPDH comprising the glycolytic index (GI) was significantly lower in RA patients compared to HC (Figure 1B).