Molecular dynamics and free energy calculations of clozapine bound to D2 and H1 receptors reveal a cardiometabolic mitigated derivative

Abstract

Most atypical antipsychotics derive from a high dropout of drug treatments due to adverse cardiometabolic side effects. These side effects are caused, in part, by the H1 receptor blockade. The current work sought a clozapine derivative with a reduced affinity for the H1 receptor while maintaining its therapeutic effect linked to D2 receptor binding. Explicit molecular dynamics simulations and end-point free energy calculations of clozapine in complex with the D2 and H1 receptors embedded in cholesterol-rich lipid bilayers were performed to analyze the intermolecular interactions and address the relevance of clozapine-functional groups. Based on that, free energy perturbation calculations were performed to measure the change in free energy of clozapine structural modifications. Our results indicate the best clozapine derivative is the iodine atom substitution for chlorine. The latter is mainly due to electrostatic interaction loss for the H1 receptor, while the halogen orientation out of the D2 active site reduces the impact on the affinity.

Communicated by Ramaswamy H. Sarma

Keywords:

• Clozapine
• drug design
• FEP
• GPCRs
• molecular dynamics
• antipsychotics
• cardiometabolic side effects

Acknowledgments

The authors acknowledge technical support of MSc. Aldo Rodriguez Guerrero (CNyN-UNAM), Engineer Jesús Alaniz (Thubat Kaal 2.0 at CNS-IPICyT, A.C) and Héctor Manuel Olivier Hernández (Xiuhcoatl Hybrid Cluster at CINVESTAV). ACCL acknowledge to CONACyT for her scholarship (CVU 756788).

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

AVL acknowledges the National Supercomputing Center- IPICYT for the computational resources supported in this research through grant TKII-AMVL001 and, Xiuhcoatl Hybrid Cluster supercomputing resources granted to AVL; LANCAD-UNAM-DGTIC-286 and PAPIIT-DGAPA-UNAM-IG200320.