Studies on the interaction between HSA and new halogenated metformin derivatives: influence of lipophilic groups in the binding ability

• Published in: Journal of biomolecular structure & dynamics Vol. 38; no. 7; pp. 2128 - 2140
• Main Authors: Chaves, Otávio Augusto, Mathew, Bijo, Parambi, Della Grace Thomas, C. S. de Oliveira, Cosme Henrique, Cesarin-Sobrinho, Dari, Lakshminarayanan, Balasubramanian, Najeeb, Sadiya, Nafna, E. K., Marathakam, Akash, Uddin, Md. Sahab, Joy, Monu, Carlos Netto-Ferreira, José
• Format: Journal Article
• Language: English
• Published: England Taylor & Francis 02.05.2020
• Subjects: human serum albumin; Metformin; pharmacokinetics profile; pharmacokinetics profile; human serum albumin; Metformin
• ISSN: 0739-1102; 1538-0254
• DOI: 10.1080/07391102.2019.1627247

In the type II diabetes mellitus, Metformin hydrochloride is recommended as a common FAD approved drug. Synthesis of novel metformin series has been widely explored, mainly due to its biological importance and to improve their pharmacokinetic profile. Generally, human serum albumin (HSA) is the main protein used to study drug viability in vitro analysis. Thus, the present study reports the synthesis of three new halogenated metformin derivatives (MFCl, MFBr and MFCF 3 ) and its interaction toward HSA by multiple spectroscopic techniques (UV-Vis, circular dichroism, steady-state, time-resolved and synchronous fluorescence), combined to computational methods (molecular docking and quantum chemical calculation). The interaction between each halogenated metformin derivative and HSA is spontaneous (ΔG°<0), entropically driven (ΔS°>0), moderate (K a and K b ≈ 10 4 M −1 ) and occurs preferentially in the subdomain IIA (close to Trp-214 residue). Molecular docking results suggested hydrogen bonding, van der Waals and hydrophobic interactions as the main binding forces. Quantum chemical calculations suggested imino groups as the most intense electrostatic negative potentials, while the positive electrostatic potential is located at the hydrogen atoms on N,N-dimethyl and the phenyl systems which can help the hydrophobic interactions. Communicated by Ramaswamy H. Sarma