Investigation of [.sup.3H]diazepam derivatives as allosteric modulators of GABAA receptor [alpha].sub.1[beta].sub.2[gamma].sub.2 subtypes: combination of molecular docking/dynamic simulations, pharmacokinetics/drug-likeness prediction, and QSAR analysis

• Published in: Structural chemistry 2023-06, Vol.34 (3), p.791
• Main Authors: Djebaili, Rachida, Kenouche, Samir, Daoud, Ismail, Melkemi, Nadjib, Belkadi, Ahlem, Mesli, Fouzia
• Format: Article
• Language: English
• Subjects: Analysis; Diazepam; GABA; Investigations; Molecular dynamics; Simulation methods
• ISSN: 1040-0400
• DOI: 10.1007/s11224-022-02029-4

In this paper, a data set of [.sup.3H] diazepam derivatives was analyzed using various computational methods: molecular docking/dynamic simulations, and QSAR analysis. The main aims of these studies are to understand the binding mechanisms by which benzodiazepines allosterically modulate GABA.sub.A receptor [alpha].sub.1[beta].sub.2[gamma].sub.2 subtypes, from inducing neuronal inhibition at lower doses to the anesthetic effect at higher doses, and also, to define the structural requirements that contribute to improving the response of GABA.sub.A/[alpha].sub.1[beta].sub.2[gamma].sub.2 receptor to benzodiazepine drugs. The results of the molecular docking study allowed selecting Ro12-6377 and proflazepam as the best modulators for the four binding sites simultaneously. Subsequently, the stability of the selected complexes was investigated by performing molecular dynamics simulation. The latter confirmed the features of both modulators to exert direct effects on the chloride-channel lining residues. Pharmacokinetics and drug-likeness profile were assessed through in silico tool. Furthermore, a QSAR analysis was conducted using an improved vemolecular dynamics simulations proposed byrsion of PLS regression. The goodness of fit and the predictive power of the resulting PLS model were estimated according to internal and external validation parameters: R.sup.2 = 0.632, R.sup.2.sub.adj = 0.584, F = 12.806; p-value = 6.2050e - 07, Q.sup.2.sub.loo = 0.639, and Q.sup.2.sub.F3 = 0.813. Clearly, the obtained results ensure the predictive ability of the developed QSAR model for the design of new high-potency benzodiazepine drugs.