Oxidative stress and galactose-deficient IgA1 as markers of progression in IgA nephropathy

Academic Article

Abstract

  • Background and objectives We assessed the activation of the oxidative stress pathway in patients with IgA nephropathy (IgAN), while evaluating the classic marker of the disease (galactose-deficient serum IgA1). Design, setting, participants, & measurements Sera from 292 patients and 69 healthy controls from Italy and the United States were assayed for advanced oxidation protein products (AOPPs), free sulfhydryl groups on albumin (SH-Alb), and IgA1 with galactose-deficient hinge-region O-glycans (Gd-IgA1). Gd-IgA1 was detected by binding to Helix aspersa agglutinin (HAA) and expressed as total Gd-IgA1 or as degree of galactose deficiency relative to a standard Gd-IgA1 myeloma protein (%HAA). Results Sera from IgAN patients showed higher levels of Gd-IgA1, %HAA, and AOPPs, but lower levels of SH-Alb in comparison to that from healthy controls. Serum levels of AOPPs significantly correlated with serum Gd-IgA1 and %HAA. The relationship between these biomarkers and clinical features at sampling and during follow-up was assessed in 62 patients with long-term follow-up. AOPPs and %HAA correlated with proteinuria at sampling and independently associated with subsequent proteinuria. Levels of AOPPs correlated with rate of decline in renal function after sampling. The combination of a high level of AOPPs and a high level of %HAA associated with decline in estimated GFR. Conclusions Serum levels of aberrantly glycosylated IgA1 are elevated and oxidative stress pathways are activated in patients with IgAN; the intensity of the stress correlated with expression and progression of the disease. We speculate that oxidative stress may modulate the nephrotoxicity of aberrantly glycosylated IgA1 in IgAN. ¬© 2011 by the American Society of Nephrology.
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    Author List

  • Camilla R; Suzuki H; Dapr√† V; Loiacono E; Peruzzi L; Amore A; Ghiggeri GM; Mazzucco G; Scolari F; Gharavi AG
  • Start Page

  • 1903
  • End Page

  • 1911
  • Volume

  • 6
  • Issue

  • 8