Molecular Dynamics and Structural Studies of Zinc Chloroquine Complexes

J Chem Inf Model. 2023 Jan 9;63(1):161-172. doi: 10.1021/acs.jcim.2c01164. Epub 2022 Dec 5.

Abstract

Chloroquine (CQ) is a first-choice drug against malaria and autoimmune diseases. It has been co-administered with zinc against SARS-CoV-2 and soon dismissed because of safety issues. The structural features of Zn-CQ complexes and the effect of CQ on zinc distribution in cells are poorly known. In this study, state-of-the-art computations combined with experiments were leveraged to solve the structural determinants of zinc-CQ interactions in solution and the solid state. NMR, ESI-MS, and X-ray absorption and diffraction methods were combined with ab initio molecular dynamics calculations to address the kinetic lability of this complex. Within the physiological pH range, CQ binds Zn2+ through the quinoline ring nitrogen, forming [Zn(CQH)Clx(H2O)3-x](3+)-x (x = 0, 1, 2, and 3) tetrahedral complexes. The Zn(CQH)Cl3 species is stable at neutral pH and at high chloride concentrations typical of the extracellular medium, but metal coordination is lost at a moderately low pH as in the lysosomal lumen. The pentacoordinate complex [Zn(CQH)(H2O)4]3+ may exist in the absence of chloride. This in vitro/in silico approach can be extended to other metal-targeting drugs and bioinorganic systems.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • COVID-19 Drug Treatment
  • COVID-19*
  • Chlorides
  • Chloroquine / chemistry
  • Chloroquine / pharmacology
  • Coordination Complexes*
  • Humans
  • Metals
  • Molecular Dynamics Simulation
  • SARS-CoV-2
  • Zinc / chemistry

Substances

  • Chloroquine
  • Zinc
  • Chlorides
  • Metals
  • Coordination Complexes