Effects of the Hyptis martiusii Benth. leaf essential oil and 1,8-cineole (eucalyptol) on the central nervous system of mice

Food Chem Toxicol. 2019 Nov:133:110802. doi: 10.1016/j.fct.2019.110802. Epub 2019 Sep 5.

Abstract

The aim of this study was to characterize the central effects of the Hyptis martiusii leaf essential oil (OEHM) and 1,8-cineole (eucalyptol) using behavioral animal models. Gas chromatography coupled to mass spectrometry (GC/MS) was used to characterize the chemical compounds present in the OEHM. For the behavioral tests, female Swiss mice treated with the OEHM (25, 50, 100 and 200 mg/kg, i.p.) and 1,8-cineole (50 mg/kg, i.p.) were used and subjected to the following tests: open field, elevated cross maze, rotarod, sodium pentobarbital- or ethyl ether-induced sleep time, pentylenetetrazol-induced convulsions, haloperidol-induced catalepsy, and ketamine-induced hyperkinesia. GC/MS analysis identified 20 constituents with the majority of them being monoterpenes and sesquiterpenes, with eucalyptol (1,8-cineol), the major sample compound (25.93%), standing out. The results showed the OEHM (25, 50 100 and 200 mg/kg, i.p.) and its major compound (50 mg/kg, i.p.) reduced animal motility in the open field test, increased pentobarbital- and ethyl ether-induced sleep time, as well as death latency in the pentylenetetrazole-induced convulsion model. However, the tested compounds were devoid of anxiolytic-like and myorelaxant activity. In addition, the OEHM (100 and 200 mg/kg, i.p.) and 1,8-cineole (50 mg/kg, i.p.) potentiated haloperidol-induced catalepsy and reduced ketamine-induced hyperkinesia. Taken together, the results suggest the OEHM has important hypnotic-sedative and antipsychotic-like effects, which appear to be due to the monoterpene 1,8-cineole, the major compound identified in the essential oil.

Keywords: 1,8-cineole; Antipsychotic-like effect; Essential oil; Hypnotic-sedative effect; Hyptis martiusii.

MeSH terms

  • Animals
  • Central Nervous System / drug effects*
  • Eucalyptol / pharmacology*
  • Eucalyptol / toxicity
  • Female
  • Hyperkinesis / drug therapy
  • Hyptis / chemistry*
  • Ketamine
  • Maze Learning / drug effects
  • Mice
  • Motor Activity / drug effects
  • Oils, Volatile / pharmacology*
  • Oils, Volatile / toxicity
  • Plant Leaves / chemistry
  • Sleep / drug effects

Substances

  • Oils, Volatile
  • Ketamine
  • Eucalyptol