Antidepressant-Like Effect of β-Lactolin, a Glycine-Threonine-Tryptophan-Tyrosine Peptide

• Published in: Journal of Nutritional Science and Vitaminology Vol. 65; no. 5; pp. 430 - 434
• Main Authors: ANO, Yasuhisa, OHYA, Rena, KONDO, Keiji
• Format: Journal Article
• Language: English
• Published: Japan Center for Academic Publications Japan 01.01.2019
• Subjects: Animals; Antidepressive Agents - pharmacology; Benzazepines - pharmacology; dairy products; depression; dopamine; Dopamine - metabolism; Frontal Lobe - drug effects; Glycine - chemistry; Hindlimb Suspension; Mice; Oligopeptides - chemistry; Oligopeptides - pharmacology; peptides; Threonine - chemistry; Tryptophan - chemistry; Tyrosine - chemistry; whey; Whey Proteins - pharmacology; peptides; whey; depression; dairy products; dopamine
• ISSN: 0301-4800; 1881-7742
• DOI: 10.3177/jnsv.65.430

The number of patients with mental illnesses, including depression, is rapidly increasing, and daily lifestyle is closely associated with the development of symptoms. Consequently, corrective measures, such as diet-based treatment for diseases, are receiving great attention. We previously showed that β-lactolin, a β-lactopeptide of glycine-threonine-tryptophan-tyrosine peptide, inhibits monoamine oxidase and improves memory impairment in mice, but the effects on depression have not been investigated. Here we showed that β-lactolin improved depression-like behavior via dopamine-D1-like receptor. Orally administered β-lactolin reduced immobility time in tail suspension test (TST). Pretreatment with SCH23390, dopamine D1-like receptor antagonist, attenuated the reduction in TST by β-lactolin. These effects were observed by the treatment with whey digest rich in β-lactolin. In addition, β-lactolin increased the levels of dopamine in the frontal cortex associated with the depression-like behavior. The present study suggests that supplements or nutraceutical compounds in whey digests (such as β-lactolin) show antidepressant-like effect.