In Vitro, D-Ribose and Formaldehyde Glycating Effects on Hen Egg White Lysozyme

Abstract

Background: Glycation causes severe damage to the protein structure, instigating different diseases like cataracts, nephropathy, vasculopathy, retinopathy, atherosclerosis, neurodegenerative disease, diabetes, and age-dependent complications. Formaldehyde, a pollutant present in human habitation, is produced endogenously or exogenously during cooking or incinerating wood, paints, furniture, chipboards, fabric etc. Its higher concentrations can cause cell damage that promotes the formation of DNA/Protein cross-links. The present study aimed to evaluate the glycating effects of formaldehyde on hen egg white lysozyme in comparison with known glycating agent D-ribose.

Methods: In this, in-vitro study, hen egg white lysozyme (HEWL) glycation with different concentrations of formaldehyde (0.25mM, 0.5mM, 1mM and 2mM) and D-ribose (0.01mM, 0.05mM, 0.1mM and 0.5mM) was examined using two different experimental conditions: concentration and time duration. Further cross-linking of protein was also analysed using SDS-PAGE technique.

Results: Glycation of HEWL treated with formaldehyde increased with increasing concentrations (0.25mM, 0.5mM, 1mM and 2mM) and time duration (1, 3, 7 and 15 days). Cross linking of HEWL showed visible glycation at 2mM concentration. Cross-linked HEWL products gave dimer at 0.25mM and 0.5mM and trimers at 1mM and 2mMat 3, 7 and 15days. However, compared to formaldehyde, D-ribose glycation at different concentrations (0.01mM, 0.05mM, 0.1mM and 0.5mM) did not show the prominent cross linking of protein.

Conclusion: Formaldehyde was found to be a more potent glycating agent compared to D-ribose. Compared to D-ribose, formaldehyde can produce protein misfolding and can be used in clinical research to establish the role of formaldehyde in patients with diseases.

Keywords: Formaldehyde; D-Ribose; Lysozyme; SDS PAGE.