title: ATP-P2X4 signaling mediates NLRP3 inflammasome activation: a novel pathway of diabetic nephropathy.
abstract: Tubulointerstitial inflammation plays a key role in the development of diabetic nephropathy (DN). Cytokines in the IL-1 family are the key pro-inflammatory cytokines of tubulointerstitial inflammation. Extracellular ATP can cause P2X receptors to activate the NOD-like receptor 3 (NLRP3) inflammasome and cause IL-1β and IL-18 maturation and release. We investigated the role of ATP-P2X4 signaling in NLRP3 inflammasome activation and renal interstitial inflammation characteristic of DN. Ex vivo studies, P2X4 showed increased expression in renal tubule epithelial cells in patients with nephropathy due to type 2 diabetes compared to those in the control group. Linear correlation analysis shows that P2X4 expression was positively related with urine IL-1β and IL-18 levels. Moreover, P2X4 expression was co-localized with NLRP3, IL-1β, and IL-18 expression. In vitro culture experiments showed NLRP3 protein expression, cleavage of caspase-1 and IL-1β, and release of IL-1β, IL-18 and ATP in HK-2 cells significantly increased after high glucose stimulation. However, apyrase, which consumes extracellular ATP, completely blocked the changes caused by high glucose. The P2 receptor antagonist suramin, P2X receptor antagonist TNP-ATP, P2X4 selective antagonist 5-BDBD, and P2X4 gene silencing attenuated NLRP3 expression, cleavage of caspase-1 and IL-1β, and release of IL-1β and IL-18 induced by high glucose. Taken together, these results suggest that ATP-P2X4 signaling mediates high glucose-induced activation of the NLRP3 inflammasome, regulates IL-1 family cytokine secretion, and causes the development of tubulointerstitial inflammation in DN.
authors: Department of Nephrology, Daping Hospital, Research Institute of Surgery, Third Military Medical University, Chongqing 400042, PR China.
authors: Kehong
authors: K
authors: Chen
authors: Jianguo
authors: J
authors: Zhang
authors: Weiwei
authors: W
authors: Zhang
authors: Jinhua
authors: J
authors: Zhang
authors: Jurong
authors: J
authors: Yang
authors: Kailong
authors: K
authors: Li
authors: Yani
authors: Y
authors: He
mesh_terms: D000255:Adenosine Triphosphate / Q000378:metabolism*; D000328:Adult; D000368:Aged; D002352:Carrier Proteins / Q000276:immunology / Q000378:metabolism*; D018929:Cell Culture Techniques; D003924:Diabetes Mellitus, Type 2 / Q000276:immunology / Q000378:metabolism; D003928:Diabetic Nephropathies / Q000276:immunology / Q000378:metabolism*; D005260:Female; D005947:Glucose / Q000378:metabolism; D006801:Humans; D058847:Inflammasomes / Q000276:immunology / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D000071199:NLR Family, Pyrin Domain-Containing 3 Protein; D009395:Nephritis, Interstitial / Q000276:immunology / Q000378:metabolism; D058848:Receptors, Purinergic P2X4 / Q000276:immunology / Q000378:metabolism*; D015398:Signal Transduction; D014162:Transfection
chemical_list: D002352:Carrier Proteins; D058847:Inflammasomes; D000071199:NLR Family, Pyrin Domain-Containing 3 Protein; C453881:NLRP3 protein, human; D058848:Receptors, Purinergic P2X4; D000255:Adenosine Triphosphate; D005947:Glucose