Pilot Study of the Tart Cherry Juice for the Treatment of Insomnia and Investigation of Mechanisms

Am J Ther. Mar/Apr 2018;25(2):e194-e201. doi: 10.1097/MJT.0000000000000584.

Abstract

Background: Insomnia is common in the elderly and is associated with chronic disease, but use of hypnotics increases the incidence of falls. Montmorency tart cherry juice has improved insomnia by self-report questionnaire.

Study question: Is insomnia confirmed by polysomnography and is tryptophan availability a potential mechanism for treating insomnia?

Study design: A placebo-controlled balanced crossover study with subjects older than 50 years and insomnia were randomized to placebo (2 weeks) or cherry juice (2 weeks) (240 mL 2 times/d) separated by a 2-week washout.

Measures and outcomes: Sleep was evaluated by polysomnography and 5 validated questionnaires. Serum indoleamine 2,3-dioxygenase (IDO), the kynurenine-to-tryptophan ratio, and prostaglandin E2 were measured. In vitro, Caco-2 cells were stimulated with interferon-gamma, and the ability of cherry juice procyanidin to inhibit IDO which degrades tryptophan and stimulates inflammation was measured. The content of procyanidin B-2 and other major anthocyanins in cherry juice were determined.

Results: Eleven subjects were randomized; 3 with sleep apnea were excluded and referred. The 8 completers with insomnia increased sleep time by 84 minutes on polysomnography (P = 0.0182) and sleep efficiency increased on the Pittsburgh Sleep Quality Index (P = 0.03). Other questionnaires showed no significant differences. The serum kynurenine-to-tryptophan ratio decreased, as did the level of prostaglandin E2 (both P < 0.05). In vitro, cherry juice procyanidin B-2 dose-dependently inhibited IDO.

Conclusions: Cherry juice increased sleep time and sleep efficiency. Cherry juice procyanidin B-2 inhibited IDO, increased tryptophan availability, reduced inflammation, and may be partially responsible for improvement in insomnia.

Publication types

  • Randomized Controlled Trial

MeSH terms

  • Aged
  • Antioxidants
  • Biflavonoids / pharmacology*
  • Biflavonoids / therapeutic use
  • Caco-2 Cells
  • Catechin / pharmacology*
  • Catechin / therapeutic use
  • Cross-Over Studies
  • Double-Blind Method
  • Female
  • Fruit and Vegetable Juices*
  • Humans
  • Indoleamine-Pyrrole 2,3,-Dioxygenase / blood
  • Kynurenine / blood
  • Male
  • Middle Aged
  • Pilot Projects
  • Placebos
  • Polysomnography
  • Proanthocyanidins / pharmacology*
  • Proanthocyanidins / therapeutic use
  • Prunus avium / chemistry*
  • Sleep / drug effects*
  • Sleep Initiation and Maintenance Disorders / blood
  • Sleep Initiation and Maintenance Disorders / diagnosis
  • Sleep Initiation and Maintenance Disorders / diet therapy*
  • Surveys and Questionnaires
  • Time Factors
  • Tryptophan / blood

Substances

  • Antioxidants
  • Biflavonoids
  • Indoleamine-Pyrrole 2,3,-Dioxygenase
  • Placebos
  • Proanthocyanidins
  • procyanidin B
  • Kynurenine
  • Tryptophan
  • Catechin