Triethylene glycol, an active component of Ashwagandha (Withania somnifera) leaves, is responsible for sleep induction

PLoS One. 2017 Feb 16;12(2):e0172508. doi: 10.1371/journal.pone.0172508. eCollection 2017.

Abstract

Insomnia is the most common sleep complaint which occurs due to difficulty in falling asleep or maintaining it. Most of currently available drugs for insomnia develop dependency and/or adverse effects. Hence natural therapies could be an alternative choice of treatment for insomnia. The root or whole plant extract of Ashwagandha (Withania somnifera) has been used to induce sleep in Indian system of traditional home medicine, Ayurveda. However, its active somnogenic components remain unidentified. We investigated the effect of various components of Ashwagandha leaf on sleep regulation by oral administration in mice. We found that the alcoholic extract that contained high amount of active withanolides was ineffective to induce sleep in mice. However, the water extract which contain triethylene glycol as a major component induced significant amount of non-rapid eye movement sleep with slight change in rapid eye movement sleep. Commercially available triethylene glycol also increased non-rapid eye movement sleep in mice in a dose-dependent (10-30 mg/mouse) manner. These results clearly demonstrated that triethylene glycol is an active sleep-inducing component of Ashwagandha leaves and could potentially be useful for insomnia therapy.

MeSH terms

  • Animals
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Plant Extracts / chemistry
  • Plant Extracts / pharmacology*
  • Plant Leaves / chemistry*
  • Polyethylene Glycols / pharmacology*
  • Sleep / drug effects
  • Sleep / physiology*
  • Sleep Aids, Pharmaceutical / pharmacology*

Substances

  • Plant Extracts
  • Sleep Aids, Pharmaceutical
  • triethylene glycol
  • Polyethylene Glycols
  • Ashwagandha

Grants and funding

This study was supported financially by grant from "Japan Society for the Promotion of Science", KAKENHI grant number 16H01881 to Yoshihiro Urade.