Characterization of methylglyoxal-modified human IgG by physicochemical methods. Issue 12 (10th September 2018)

• Record Type: Journal Article
• Authors: Khan, Mohd. Adnan; Arif, Zarina; Moinuddin, ; Alam, Khursheed
• Is Part Of: Journal of biomolecular structure & dynamics. Volume 36:Issue 12(2018)
• Page Start: 3172
• Page End: 3183
• Publication Date: 2018-09-10
• Subjects: Human IgG -- methylglyoxal -- hyperglycemia -- protein aggregate -- crosslink; IgG: Immunoglobulin G -- MGO: Methylglyoxal -- AGEs: Advanced glycation end products -- SEM: Scanning electron microscope -- TEM: Transmission electron microscope -- ANS: 8-anilinonaphthalene-1-sulfonic acid -- DNPH: Dinitrophenyl hydrazine -- FT-IR: Fourier transform infrared spectroscopy -- DTNB: 5, 5'-dithiobis-(2-nitrobenzoic acid) -- NBT: Nitroblue tetrazolium; Biomolecules -- Periodicals; Molecular structure -- Periodicals; Molecular Biology -- Periodicals; Biomechanics -- Periodicals; 572
• DOI: 10.1080/07391102.2017.1383309
• Languages: English
• ISSNs: 0739-1102

Abstract

Abstract : Human IgG is a defence protein and quite reactive to dicarbonyls. In this study, methylglyoxal-induced modification of IgG was examined by various biochemical and biophysical methods. The methylglyoxal-induced changes in IgG were monitored by UV-visible and fluorescence spectroscopy, Fourier transform infrared spectroscopy, 1-anilinonaphthalene-8-sulfonic acid (ANS), and thermal denaturation studies. Aggregate formation was studied by Thioflavin T (ThT), Congo red (CR) and scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Spectroscopic studies suggested gross changes in MGO-modified IgG. Fluorogenic AGEs appeared during modification and the MGO-modified IgG gained thermostability. The reaction produced oxidative stress in the medium because carbonyl content increased manifold and sulfhydryl groups decreased. Enhanced binding of the MGO-modified IgG by Congo red and Thioflavin T suggests crosslinking and aggregation. This was supported by SEM and TEM results. Abstract :