ArticleNutrients2019
Tryptophan-Tyrosine Dipeptide, the Core Sequence of β-Lactolin, Improves Memory by Modulating the Dopamine System.
Article in Nutrients, 2019. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 17 papers, 1 of them a synthesis that pooled it.
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The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
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Who cites it
17 citing papers in PubMed, 1 synthesis or guideline pooled it, 28 citations in OpenAlex.
- The effects ofFrontiers in nutrition · 2025Pooled it
- Supplementation with whey peptide rich in β-lactolin improves trait anxiety and subjective stress in healthy adults: a randomized, double-blind, placebo-controlled study.Scientific reports · 2024Trial
- β-Lactolin Enhances Neural Activity, Indicated by Event-Related P300 Amplitude, in Healthy Adults: A Randomized Controlled Trial.Journal of Alzheimer's disease : JAD · 2021Trial
- Patient-derived prostate organoids identify MAOA as a disease severity-associated molecular marker in chronic pelvic pain syndrome.Scientific reports · 2026Article
- Marine-derived PUFAs and peptides for aging-related memory deficits: processing methods, pharmacokinetics, mechanistic insights, and clinical application.Frontiers in nutrition · 2026Review
- Enhancement of memory and emotional functions by long-term ingestion of protease-treated porcine liver extract in mice.Scientific reports · 2025Article
- Protective Effect of Whey Protein Supplement Against Rotenone Induced Motor Dysfunction in a Rat Model of Parkinson Disease.Advanced biomedical research · 2024Article
- A memory-improving dipeptide, Tyr-Pro, can reach the mouse brain after oral administration.Scientific reports · 2023Article
- Oyster-derived dipeptides RI, IR, and VR promote testosterone synthesis by reducing oxidative stress in TM3 cells.Food science & nutrition · 2023Article
- Article
- Systematic screening and structural characterization of dipeptides using offline 2D LC-LTQ-Orbitrap MS: A case study ofJournal of pharmaceutical analysis · 2022Article
- Exogenous Bioactive Peptides Have a Potential Therapeutic Role in Delaying Aging in Rodent Models.International journal of molecular sciences · 2022Review
- Regional Brain Analysis of Modified Amino Acids and Dipeptides during the Sleep/Wake Cycle.Metabolites · 2021Article
- Effects of β-Lactolin on Regional Cerebral Blood Flow within the Dorsolateral Prefrontal Cortex during Working Memory Task in Healthy Adults: A Randomized Controlled Trial.Journal of clinical medicine · 2021Article
- β-Lactolin Reduces Age-Related Inflammation and Cognitive Decline.Frontiers in nutrition · 2021Article
- Article
- Preventive Effects of Tryptophan-Methionine Dipeptide on Neural Inflammation and Alzheimer's Pathology.International journal of molecular sciences · 2019Article
Corrections and comments
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Authors and funding
6 authors at 2 institutions in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
Tryptophan-tyrosine (WY)-related peptides including the β-lactopeptide of the glycine-threonine-tryptophan-tyrosine peptide, β-lactolin, improve spatial memory. However, whether and how the WY dipeptide as the core sequence in WY-related peptides improves memory functions has not been investigated. This study assessed the pharmacological effects of the WY dipeptide on memory impairment to elucidate the mechanisms. Here, we showed that oral administration of dipeptides of WY, tryptophan-methionine (WM), tryptophan-valine, tryptophan-leucine, and tryptophan-phenylalanine improved spontaneous alternation of the Y-maze test in scopolamine-induced amnesic mice. In contrast, tyrosine-tryptophan, methionine-tryptophan, tryptophan, tyrosine, and methionine had no effect. These results indicated that the conformation of dipeptides with N-terminal tryptophan is required for their memory improving effects. WY dipeptide inhibited the monoamine oxidase B activity in vitro and increased dopamine levels in the hippocampus and frontal cortex, whereas tryptophan did not cause these effects. In addition, the treatment with SCH-23390, a dopamine D1-like receptor antagonist, and the knockdown of the hippocampal dopamine D1 receptor partially attenuated the memory improvement induced by the WY dipeptide. Importantly, WY dipeptide improved the spontaneous alternations of the Y-maze test in aged mice. These results suggest that the WY dipeptide restores memory impairments by augmenting dopaminergic activity. The development of supplements rich in these peptides might help to prevent age-related cognitive decline.
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Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.