Structural basis of drug recognition by human serum albumin

BACKGROUND: Human serum albumin (HSA), the most abundant protein in plasma, is a monomeric multi-domain macromolecule with nine observed binding sites for endogenous and exogenous ligands. HSA displays an extraordinary ligand binding capacity as a depot and carrier for many compounds including most acidic drugs. Consequently, HSA has the potential to influence the pharmacokinetics and pharmacodynamics of drugs. OBJECTIVE: In this review, the structural determinants of drugs binding mode to all the multiple sites of HSA has been analyzed and discussed in detail. Moreover, insight into the allosteric and competitive mechanisms underpinning drug recognition, delivery, and efficacy have been analyzed and discussed. CONCLUSION: As several factors can modulate drug binding to HSA (e.g., concurrent administration of drugs competing for the same binding site, ligand binding to allosteric-coupled clefts, genetic inherited diseases, pathological conditions, and age) the modulation of ligand binding to HSA is relevant not only under physiological conditions, but also in the pharmacological therapy management.  .