Glycation of Immunoglobulin-G from Pentose Sugar: A Cause for Structural Perturbations

Abstract

Background: Glycation of immunoglobulin-G (IgG) molecule with monosaccharides may cause significant structural disability thus resulting in their loss of function. The accumulation of AGEs formed from glycation play an important role in the aliments associated with metabolic diseases. Therefore, excess of sugar in plasma, interferes with the functioning of IgG and may contribute to wide range of diabetes-associated complications. The long-term formation of these heterogeneous AGEs may accumulate and can affect plasma proteins, especially long-lived proteins. In this study, we analyze glycation of immunoglobulin-G (IgG) with 2’-deoxyribose (deoxyribose) instigated modification in IgG structure and AGEs formation. Methods: This study aims to glycate IgG from varying concentrations of a pentose sugar, 2’-deoxy-ribose (deoxyribose). Post glycation of IgG, both the native and its glycated analogue were characterized by various physicochemical methods and techniques. The glycated protein will be assessed for its stability and perturbations by UV-VIS., fluorescence and FT-IR spectroscopic techniques. Moreover, the early glycation product will be done by NBT assay and other biochemical parameters like HMF, carbonyl content and thioflavin-T assays were also performed to see the biochemical changes induced in the glycated IgG macromolecule. Results: Glycation of protein macromolecules generates stable early glycation products (Amadori products). Later on, these Amadori products involve in series of chemical reactions to form more stable advanced glycation end products (AGEs).Our experimental study results could validate the modification in IgG structure and AGEs formation. Conclusion: The formation of IgG-AGEs from glycation of IgG with deoxyribose could exert cellular toxicity and might initiates secondary complications of diabetes. Therefore, this study emphasized on glycation reaction of IgG from deoxyribose and which has not been reported yet.

Communal interaction of glycation and gut microbes in diabetes mellitus, Alzheimer's disease, and Parkinson's disease pathogenesis

“…Accounting for glycation in immune interactions, fibrinogen was reported to induce an adaptive immune response by elevating cytokines upon its glycation 261 . Another study demonstrated that glycated immunoglobulin gamma can form IgG‐AGEs adduct and raise cellular toxicity, which may trigger various diabetic complications 262 …”

“…261 Another study demonstrated that glycated immunoglobulin gamma can form IgG-AGEs adduct and raise cellular toxicity, which may trigger various diabetic complications. 262 We have reported that regular curd and yogurt (containing MG) consumption can lead to the glycation of proteins, inflammation, and oxidative stress that may cause diabetes. 139 Therefore, inhibition of this process is evolving as a practical therapeutic approach to retard aging and events of disease development.…”

Identification of Glycoxidative Lesion in Isolated Low-Density Lipoproteins from Diabetes Mellitus Subjects

“…The nextstep is to incubate the sample mixtures at physiological temperature, which is 37 • C, until the yellow mixture changes to a purple mixture. The absorbance for ketoamine detection was recorded at 525 nm wavelength, and the molar extinction coefficient of 12,640 M −1 cm −1 was used to calculate ketoamine concentration (nmol mL −1 ) [28].…”