The effect of nutmeg essential oil constituents on Novikoff hepatoma cell viability and communication through Cx43 gap junctions

Biomed Pharmacother. 2021 Mar:135:111229. doi: 10.1016/j.biopha.2021.111229. Epub 2021 Feb 1.

Abstract

Essential oils from plants are a potential source of molecules having anti-inflammatory, anticancer, cardiotropic, and other activities. However, most of these effects lack mechanistic explanations and structure-activity relationship testing. In the present study, we: 1) identified the nutmeg essential oil (NEO) composition; 2) using molecular docking, we determined the putative regulatory binding sites on the connexin 43 (Cx43) that is responsible for gap junction-dependent intercellular communication (GJIC) in the majority of tissues; 3) examined the effect of NEO and its three constituents - sabinene, α-pinene, and α-copaene - on GJ conductance and gating in Novikoff cells expressing endogenous Cx43; and 4) verified whether NEO effects on GJIC correlated with its action on Novikoff cell viability, proliferation, and colony formation capability. Our results revealed NEO and its constituents as potent and efficient Cx43 GJ inhibitors acting by slow gating mechanism. In addition, NEO reduced Novikoff hepatoma cell viability, proliferation, and colony formation capability; however, this was achieved at higher doses and was unrelated to its effects on GJIC.

Keywords: Cancer cells; Colony formation; Gap junctions; Nutmeg essential oil; Proliferation; Viability.

MeSH terms

  • Animals
  • Antineoplastic Agents, Phytogenic / isolation & purification
  • Antineoplastic Agents, Phytogenic / pharmacology*
  • Cell Line, Tumor
  • Cell Proliferation / drug effects
  • Cell Survival / drug effects
  • Connexin 43 / metabolism*
  • Gap Junctions / drug effects*
  • Gap Junctions / metabolism
  • Gap Junctions / pathology
  • Liver Neoplasms, Experimental / drug therapy*
  • Liver Neoplasms, Experimental / metabolism
  • Liver Neoplasms, Experimental / pathology
  • Molecular Docking Simulation
  • Myristica* / chemistry
  • Oils, Volatile / isolation & purification
  • Oils, Volatile / pharmacology*
  • Plant Oils / isolation & purification
  • Plant Oils / pharmacology*
  • Protein Binding
  • Rats
  • Signal Transduction

Substances

  • Antineoplastic Agents, Phytogenic
  • Connexin 43
  • Gja1 protein, rat
  • Oils, Volatile
  • Plant Oils