The study on the effect of non-enzymatic glycation on the interaction of human serum albumin and sodium-fluorescein, via spectroscopic analyses

The study on the effect of non-enzymatic glycation on the interaction of human serum albumin and sodium-fluorescein, via spectroscopic analyses

4^th International Congress on Drug Discovery, Designing and Development & International Conference and Exhibition on Biochemistry, Molecular Biology: R&D
November 02-03, 2017 Chicago, USA

Priyankar Sen, Sadaf Fatima, Tamanna Anwar, Nabeel Ahmad and Asimul Islam

VIT University, India

Scientific Tracks Abstracts : J Pharmacol Ther Res

Abstract:

The binding of SF to Human Serum Albumin (HSA) has been predicted by molecular docking and investigated by circular dichroism (CD) and fluorescence spectroscopy with or without glycation at temperatures 296K, 301K, and 310K. The binding parameters were calculated by quenching of emission spectrum of a constant concentration of SF (2 μM) at 513 nm against increasing concentrations of glycated or unmodified HSA as quencher starting from stochiometry ratio of 1:1. Sodium Fluorescein (SF) is a fluorescent tracer dye used extensively in diagnostic tools in the field of Ophthalmology, particularly in intravenous fluorescein angiography (IVFA). The HSA-SF interaction found to be a static binding. The SternVolmer constants (Ksv) were in the range of ~104 M-1 and other thermodynamic parameters like enthalpy (ΔH0), free energy (ΔG0) and entropy (ΔS0) are like albumin ligand bindings reported by previous workers. The interactions were found to be spontaneous, irrespective of temperature or glycation. Glycated HSA is clinically used to monitor unstable glycemic controls in diabetic patients. 39% increase in binding affinity (log K) and free energy (ΔG0) is reported on glycation at 310 K (room temperature), which may be important in the SF based angiographies. Further, on glycation HSA-SF binding seems to change from an enthalpy-driven to an entropy-driven reaction. SF shows best binding to FA binding site III of HSA, which also overlaps with drug binding site II of sub domain IIIA. Leu-430 seems to play a pivotal role in the interaction. This is the first report of glycated HSA and SF binding and comparison between the thermodynamic parameters of the bindings in the absence and presence of glycation at different temperatures.

Biography:

Priyankar Sen is working in the field of protein folding and protein ligand interactions for the enhanced understanding of the molecular behavior of proteins, specifically albumins. He has done his PhD from Rizwan Khan’s Lab in IBU, Aligarh Muslim University, India and Post-doctorate from Salunke’s Lab, NII, New Delhi. Out of 5 years’ Doctoral and 8 years Post-doctoral research, he has published 21 papers in international peer reviewed journals. He is currently working as Assistant Professor in VIT University. Currently, he is focusing on expression and modification of therapeutically important proteins and further scale up in bioreactors.

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