In Silico and In Vitro Screening of Some Pregnane Glycosides Isolated from Certain Caralluma Species as SARS-COV-2 Main Protease Inhibitors

Chem Biodivers. 2024 Apr;21(4):e202301786. doi: 10.1002/cbdv.202301786. Epub 2024 Mar 11.

Abstract

SARS-CoV-2 caused pandemic represented a major risk for the worldwide human health, animal health and economy, forcing extraordinary efforts to discover drugs for its prevention and cure. Considering the extensive interest in the pregnane glycosides because of their diverse structures and excellent biological activities, we investigated them as antiviral agents against SARS-COV-2. We selected 21 pregnane glycosides previously isolated from the genus Caralluma from Asclepiadaceae family to be tested through virtual screening molecular docking simulations for their potential inhibition of SARS-CoV-2 Mpro. Almost all target compounds showed a more or equally negative docking energy score relative to the co-crystallized inhibitor X77 (S=-12.53 kcal/mol) with docking score range of (-12.55 to -19.76 kcal/mol) and so with a potent predicted binding affinity to the target enzyme. The activity of the most promising candidates was validated by in vitro testing. Arabincoside C showed the highest activity (IC50=35.42 μg/ml) and the highest selectivity index (SI=9.9) followed by Russelioside B (IC50=50.80 μg/ml), and Arabincoside B (IC50=53.31 μg/ml).

Keywords: Arabincosides; Caralluma; Protease Inhibitors, Russeliosides; anti-SARS-CoV-2; molecular docking.

MeSH terms

  • Animals
  • Antiviral Agents / chemistry
  • Antiviral Agents / pharmacology
  • Apocynaceae* / chemistry
  • COVID-19*
  • Coronavirus 3C Proteases* / antagonists & inhibitors
  • Glycosides / chemistry
  • Glycosides / pharmacology
  • Humans
  • Molecular Docking Simulation
  • Molecular Dynamics Simulation
  • Pregnanes / chemistry
  • Pregnanes / pharmacology
  • Protease Inhibitors / chemistry
  • Protease Inhibitors / pharmacology
  • SARS-CoV-2 / drug effects
  • SARS-CoV-2 / metabolism

Substances

  • 3C-like proteinase, SARS-CoV-2
  • Antiviral Agents
  • Coronavirus 3C Proteases
  • Glycosides
  • pregnane glycoside
  • Pregnanes
  • Protease Inhibitors
  • small molecule X77