title: Netrin-1 regulates Th1/Th2/Th17 cytokine production and inflammation through UNC5B receptor and protects kidney against ischemia-reperfusion injury.
abstract: Overwhelming evidence suggests that ischemia-reperfusion injury of the kidney is an inflammatory disease mediated by innate and adoptive immune systems. The neuronal guidance molecule netrin-1 was shown to modulate inflammatory responses. Given that ischemic kidney is particularly prone to reperfusion-elicited inflammation, we sought to determine the function of netrin-1 and its receptor UNC5B in ischemia-reperfusion-induced inflammation. Renal ischemia-reperfusion caused a rapid decrease in serum netrin-1 levels. Administration of recombinant netrin-1 before or after renal ischemia-reperfusion reduced kidney injury, apoptosis, monocyte and neutrophil infiltration, and cytokine (IL-6, IL-1beta, and TNF-alpha) and chemokine (MCP-1, macrophage-derived cytokine, monokine-induced IFN-gamma, keratinocyte-derived chemokine, and chemokine with 6 cysteines) production. Analysis for different netrin-1 receptors on leukocytes showed very high expression of UNC5B but not UNC5C, UNC5D, neogenin, or deleted in colorectal cancer. Expression of UNC5A was low. Neutralization of UNC5B receptor reduced netrin-1-mediated protection against renal ischemia-reperfusion injury, and it increased monocyte and neutrophil infiltration, as well as serum and renal cytokine and chemokine production, with increased kidney injury and renal tubular cell apoptosis. Finally, investigation into netrin-1's effect on CD4 T cell stimulation showed suppression of Th1/Th2/Th17 cytokine (IL-2, IL-6, IL-10, IL-13, IL-17, IFN-gamma, IL-4, and TNF-alpha) production in vitro. Our studies demonstrate that netrin-1 acting through UNC5B receptor reduces renal ischemia-reperfusion injury and its associated renal inflammation.
authors.affiliation: Division of Nephrology, The Pennsylvania State University College of Medicine, Hershey, PA 17033, USA.
authors.forename: Raghu Kempegowda
authors.initials: RK
authors.lastname: Tadagavadi
authors.forename: Weiwei
authors.initials: W
authors.lastname: Wang
authors.forename: Ganesan
authors.initials: G
authors.lastname: Ramesh
mesh_terms: D000818:Animals; D004195:Disease Models, Animal; D018836:Inflammation Mediators / Q000502:physiology*; D020381:Interleukin-17 / Q000096:biosynthesis*; D007674:Kidney Diseases / Q000276:immunology / Q000473:pathology / Q000503:physiopathology / Q000517:prevention & control*; D007677:Kidney Function Tests; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D009414:Nerve Growth Factors / Q000502:physiology*; D000075386:Netrin Receptors; D000075388:Netrin-1; D011956:Receptors, Cell Surface / Q000037:antagonists & inhibitors / Q000502:physiology*; D015427:Reperfusion Injury / Q000276:immunology / Q000473:pathology / Q000503:physiopathology / Q000517:prevention & control*; D018417:Th1 Cells / Q000276:immunology* / Q000378:metabolism / Q000473:pathology; D018418:Th2 Cells / Q000276:immunology* / Q000378:metabolism / Q000473:pathology; D025521:Tumor Suppressor Proteins / Q000502:physiology*
chemical_list: D018836:Inflammation Mediators; D020381:Interleukin-17; D009414:Nerve Growth Factors; D000075386:Netrin Receptors; C000617353:Ntn1 protein, mouse; D011956:Receptors, Cell Surface; D025521:Tumor Suppressor Proteins; C000617308:Unc5A protein, mouse; D000075388:Netrin-1