Fig 2: Detection of P2X1-6 receptor expression in FG-labeled neurons of L4+L5 DRG. Photomicrographs presenting fluorescence of FG-labeled and P2XR1-6 IR neurons in L4+L5 DRG from the sham and the CCI groups. Yellow arrows indicate the P2XR+/FG+ double-labeled neurons. Scale bars, 100 µm. IR, immunoreactive; FG, Fluorogold; DRG, dorsal root ganglion; CCI, chronic constriction injury.

Fig 3: Inhibition of P2RX1 promotes the efficiency of anti-TNF-a therapy in mouse colitis. (A, B) WT mice were treated with 2% DSS for 7 days. Anti-TNF-a monoclonal antibody (mAb) (0.1 mg/day) or/and P2RX1 inhibitor (NF449, 10 mg/kg/day) was/were administrated for 7 days. Weight loss (A) and disease activity index (DAI) (B) were calculated (n = 6 per group). Statistical analyses were performed at day 7. (C) At day 7, RT-qPCR was performed to detect inflammatory cytokine expression (n = 4 per group). (D) At day 7, colonic neutrophils were determined by cytometry (n = 4 per group). *P < 0.05, **P < 0.01, and ***P < 0.001.

Fig 4: P2RX1 ablation relieves DSS-induced mouse colitis. (A, B) WT and P2rx1 -/- mice were treated with 2% DSS for 7 days. Weight loss (A) and disease activity index (DAI) (B) were calculated (n = 6 per group). (C) Colon length of WT and P2rx1 -/- mice was measured at days 0 and 7. Representative colon tissues at day 7 were shown (n = 6 per group). Scale bar is 1 cm. (D) Histologic score of WT and P2rx1 -/- mice at days 0 and 7 was determined according to pathological examinations (n = 6 per group). (E) WT and P2rx1 -/- mice were exposed to 3% DSS for 7 days, and survival status was monitored for 25 days (n = 10 per group). *P < 0.05, **P < 0.01, and ***P < 0.001.

Fig 5: Purinergic receptor P2RX1 expression is increased in activated colitis. (A) Expression of purinergic receptors were analyzed in two Gene Expression Omnibus (GEO) datasets (GSE59071 and GSE53306) containing expression profile of actively inflamed mucosa from colitis patients, and one GEO dataset (GSE22307) containing expression profile of colon tissues from DSS-induced mouse colitis. Venn diagram of significantly upregulated and downregulated genes was shown. (B, C) Expression profiles of P2RX1 in the GSE59071, GSE53306, GSE22307, and GSE16879 datasets. *P < 0.05, **P < 0.01, and ***P < 0.001.