Human serum albumin

About: Human serum albumin is a research topic. Over the lifetime, 9402 publications have been published within this topic receiving 269029 citations. The topic is also known as: serum albumin & ALB.

Interaction of an antiepileptic drug, lamotrigine with human serum albumin (HSA): Application of spectroscopic techniques and molecular modeling methods.

Abstract: Lamotrigine (an epileptic drug) interaction with human serum albumin (HSA) was investigated by fluorescence, UV-Vis, FTIR, CD spectroscopic techniques, and molecular modeling methods. Binding constant (Kb) of 5.74×103 and number of binding site of 0.97 showed that there is a slight interaction between lamotrigine and HSA. Thermodynamic studies was constructed using the flourimetric titrations in three different temperatures and the resulted data used to calculate the parameters using Vant Hoff equation. Decreased Stern Volmer quenching constant by enhanced temperature revealed the static quenching mechanism. Negative standard enthalpy (ΔH) and standard entropy (ΔS) changes indicated that van der Waals interactions and hydrogen bonds were dominant forces which facilitate the binding of Lamotrigine to HSA, the results were confirmed by molecular docking studies which showed no hydrogen binding. The FRET studies showed that there is a possibility of energy transfer between Trp214 and lamotrigine. Also the binding of lamotrigine to HSA in the studied concentrations was not as much as many other drugs, but the secondary structure of the HSA was significantly changed following the interaction in a way that α-helix percentage was reduced from 67% to 57% after the addition of lamotrigine in the molar ratio of 4:1 to HSA. According to the docking studies, lamotrigine binds to IB site preferably.

Oxidation of the albumin thiol to sulfenic acid and its implications in the intravascular compartment

Abstract: Human serum albumin (HSA) is the most abundant protein in the intravascular compartment. It possesses a single thiol, Cys34, which constitutes ~80% of the total thiols in plasma. This thiol is able to scavenge plasma oxidants. A central intermediate in this potential antioxidant activity of human serum albumin is sulfenic acid (HSA-SOH). Work from our laboratories has demonstrated the formation of a relatively stable sulfenic acid in albumin through complementary spectrophotometric and mass spectrometric approaches. Recently, we have been able to obtain quantitative data that allowed us to measure the rate constants of sulfenic acid reactions with molecules of analytical and biological interest. Kinetic considerations led us to conclude that the most likely fate for sulfenic acid formed in the plasma environment is the reaction with low molecular weight thiols to form mixed disulfides, a reversible modification that is actually observed in ~25% of circulating albumin. Another possible fate for sulfenic acid is further oxidation to sulfinic and sulfonic acids. These irreversible modifications are also detected in the circulation. Oxidized forms of albumin are increased in different pathophysiological conditions and sulfenic acid lies in a mechanistic junction, relating oxidizing species to final thiol oxidation products.

Interplay of multiple interaction forces: Binding of tyrosine kinase inhibitor nintedanib with human serum albumin

Abstract: In this study, we have investigated the binding affinity of the newly approved tyrosine kinase inhibitor nintedanib (NIB) with human serum albumin under simulated physiological condition. The obtained results demonstrate that fluorescence intensity of human serum albumin (HSA) gets quenched by NIB and quenching occurs in static manner. Binding parameters calculated from modified Stern-Volmer equation shows that the drug binds to human serum albumin with a binding constant in the order of 10(3), with the number of binding sites approximately equal to one. Synchronous fluorescence data deciphered the change in the microenvironment of tryptophan (Trp) residue in HSA. Circular dichroism data showed an increase in helical content upon drug binding. Dynamic light scattering measurements deciphered the reduction in hydrodynamic radii of the protein, further differential scanning calorimetry results shows that nintedanib increase the thermostability of HSA. Molecular docking results demonstrated that major binding forces involved in the complex formation are hydrogen bonding and hydrophobic interaction.