IMPACT OF GLYCOXIDATION ON STRUCTURAL AND IMMUNOLOGICAL CHARACTERISTICS OF IGG ISOLATED FROM DIABETES TYPE II PATIENTS: A CLINICAL STUDY

2^nd International Conference on Metabolic Syndrome

August 10-11, 2017 | London, UK

Sidra Islam and Moinuddin

Aligarh Muslim University, India

Posters & Accepted Abstracts: J Metabolic Synd

Abstract :

Immunoglobulin G (IgG), a 150 kDa molecule and the most abundant serum protein has been described as sensitive to glycation, nitration, oxidation and other modifications. Amongst these post translational modifications, glycation and oxidation being most common, deserves special attention. Increasing evidences suggest the role of glycoxidation in the onset and progression of diabetes type II (T2DM). This study was designed to elaborate the cumulative effect of glycation (using Methylglyoxal) and oxidation (using Hydroxyl Radical) on IgG with reference to T2DM. We found appreciable binding of T2D auto-antibodies towards epitopes in hydroxyl radical modified methylglyoxal glycated IgG (OHâ�¢-MG-IgG). Furthermore, spectroscopic characterization of IgG isolated from T2D patients (T2D-IgG) revealed structural changes in comparison to IgG from healthy human subjects (NH-IgG); with hyperchromicity in UV absorbance spectroscopy, quenching in fluorescence spectroscopy, decreased �² sheet content in far-UV CD spectroscopic analysis and shifting of amide I and II bands in FTIR spectroscopy. OHâ�¢-MG induced damage in T2D-IgG was evaluated by anti-OHâ�¢-MG antibodies (generated in female rabbits) using competitive binding immunoassay. Compared to NH-IgG, T2D-IgG was observed to be more specific towards the immunogen (OHâ�¢-MG-IgG). Our results confirm that IgG in T2D patients is prone to glycoxidation induced structural damage leading to the generation of neo-epitopes that renders the protein immunogenic.