Dataset Information

P2X7 deficiency attenuates renal injury in experimental glomerulonephritis.

ABSTRACT: The P2X7 receptor is a ligand-gated cation channel that is normally expressed by a variety of immune cells, including macrophages and lymphocytes. Because it leads to membrane blebbing, release of IL-1beta, and cell death by apoptosis or necrosis, it is a potential therapeutic target for a variety of inflammatory diseases. Although the P2X7 receptor is usually not detectable in normal renal tissue, we previously reported increased expression of both mRNA and protein in mesangial cells and macrophages infiltrating the glomeruli in animal models of antibody-mediated glomerulonephritis. In this study, we used P2X7-knockout mice in the same experimental model of glomerulonephritis and found that P2X7 deficiency was significantly renoprotective compared with wild-type controls, evidenced by better renal function, a striking reduction in proteinuria, and decreased histologic glomerular injury. In addition, the selective P2X7 antagonist A-438079 prevented the development of antibody-mediated glomerulonephritis in rats. These results support a proinflammatory role for P2X7 in immune-mediated renal injury and suggest that the P2X7 receptor is a potential therapeutic target.

SUBMITTER: Taylor SR

PROVIDER: S-EPMC2689903 | biostudies-other | 2009 Jun

REPOSITORIES: biostudies-other

ACCESS DATA

Publications

P2X7 deficiency attenuates renal injury in experimental glomerulonephritis.

Taylor Simon R J SR Turner Clare M CM Elliott James I JI McDaid John J Hewitt Reiko R Smith Jennifer J Pickering Matthew C MC Whitehouse Darren L DL Cook H Terence HT Burnstock Geoffrey G Pusey Charles D CD Unwin Robert J RJ Tam Frederick W K FW

Journal of the American Society of Nephrology : JASN 20090423 6

The P2X7 receptor is a ligand-gated cation channel that is normally expressed by a variety of immune cells, including macrophages and lymphocytes. Because it leads to membrane blebbing, release of IL-1beta, and cell death by apoptosis or necrosis, it is a potential therapeutic target for a variety of inflammatory diseases. Although the P2X7 receptor is usually not detectable in normal renal tissue, we previously reported increased expression of both mRNA and protein in mesangial cells and macrop ...[more]

PMID: 19389853

Similar Datasets

Project description:BACKGROUND & AIMS:The severity of sepsis can be linked to excessive inflammatory responses resulting in hepatic injury. P2X7 receptor activation by extracellular ATP (eATP) exacerbates inflammation by augmenting cytokine production; while CD39 (ENTPD1) scavenges eATP to generate adenosine, thereby limiting P2X7 activation and resulting in A2A receptor stimulation. We aim to determine how the functional interaction of P2X7 receptor and CD39 control the macrophage response, and consequently impact on sepsis and liver injury. METHODS:Sepsis was induced by cecal ligation and puncture in C57BL/6 wild-type (WT) and CD39-/- mice. Several in vitro assays were performed using peritoneal or bone marrow derived macrophages to determine CD39 ectonucleotidase activity and its role in sepsis-induced liver injury. RESULTS:CD39 expression in macrophages limits ATP-P2X7 receptor pro-inflammatory signaling. P2X7 receptor paradoxically boosts CD39 activity. Inhibition and/or deletion of P2X7 receptor in LPS-primed macrophages attenuates cytokine production and inflammatory signaling as well as preventing ATP-induced increases in CD39 activity. Septic CD39-/- mice exhibit higher levels of inflammatory cytokines and show more pronounced liver injury than WT mice. Pharmacological P2X7 blockade largely prevents tissue damage, cell apoptosis, cytokine production, and the activation of inflammatory signaling pathways in the liver from septic WT, while only attenuating these outcomes in CD39-/- mice. Furthermore, the combination of P2X7 blockade with adenosine A2A receptor stimulation completely inhibits cytokine production, the activation of inflammatory signaling pathways, and protects septic CD39-/- mice against liver injury. CONCLUSIONS:CD39 attenuates sepsis-associated liver injury by scavenging eATP and ultimately generating adenosine. We propose boosting of CD39 would suppress P2X7 responses and trigger adenosinergic signaling to limit systemic inflammation and restore liver homeostasis during the acute phase of sepsis. Lay summary: CD39 expression in macrophages limits P2X7-mediated pro-inflammatory responses, scavenging extracellular ATP and ultimately generating adenosine. CD39 genetic deletion exacerbates sepsis-induced experimental liver injury. Combinations of a P2X7 antagonist and adenosine A2A receptor agonist are hepatoprotective during the acute phase of abdominal sepsis.

Project description:Evolution of glomerulonephritis (GN) to tubulointerstitial disease is a universal antecedent to the development of chronic kidney disease (CKD). There is also evidence that angiotensin converting enzyme (ACE) inhibition may attenuate the development of CKD in some forms of glomerulonephritis. We tested the role of ACE inhibition in a model of GN in which complement-dependent tubulointerstitial disease develops. GN was induced in C57BL/6 mice with intraperitoneal injections of horse spleen apoferritin (HSA) using lipopolysaccharide (LPS) as an adjuvant. Four groups of six animals were studied: saline-injected control mice treated with captopril or water, and GN mice treated with captopril or water. GN developed in all HSA-treated animals. In those receiving captopril, however, proteinuria (albumin/creatinine ratio) was significantly reduced by captopril treatment. Array screening was used to examined the expression of collagen-related genes and determine if these effects could be mediated by regulation of collagen genes. Six genes were identified for further analysis by quantitative RT-PCR. This model demonstrates that tubulointerstitial disease can be attenuated by ACE inhibition, with clinical, histologic, and gene expression measures. All protocols were approved by the Institutional Animal Care and Use Committee at SUNY Upstate Medical University. We employed four groups of six mice each: saline-injected control mice with and without captopril, and GN with and without captopril. C57BL/6 mice were purchased from The Jackson Laboratories (Bar Harbor, ME). Glomerulonephritis (GN) was induced by intraperitoneal (i.p.) injection of 10 mg of apoferritin from horse spleen (HSA, Sigma, St. Louis, MO) five days per week, with i.p. injection of 100 micrograms lipopolysaccharide (LPS, from Salmonella minnesota; EMD Biosciences, La Jolla, CA), as adjuvant, three times per week. Control animals received equal volumes of 0.15 M NaCl by i.p. injection. Injections were begun when the mice were approximately eight weeks of age and were continued for six weeks. Captopril, at 100 mg/kg/day was given in the drinking water. After 9 weeks, the animals were euthanized and kidneys were removed for RNA purification and analysis.

Dataset Information

P2X7 deficiency attenuates renal injury in experimental glomerulonephritis.

Publications

P2X7 deficiency attenuates renal injury in experimental glomerulonephritis.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets