Preparation of β-lactoglobulin-derived tryptophan peptide and its effect on anxiety-like behaviors in Zebrafish

Abstract

This study aimed to obtain three Trp-containing peptides from β-lactoglobulin and study their effects on anxiety-like behaviors in zebrafish. Three Trp-containing peptides were prepared from β-lactoglobulin by selective enzymatic hydrolysis and identified by UPLC-Q-TOF MS/MS. The anxiety-like behaviors of zebrafish were reduced after two weeks of administrated of β-lactoglobulin Trp peptides (LAWP), VAGTWY, VAGTW and G TW(concentration of 56 μg/mL or 500 μg/mL). As an index of serotonergic activity, we assessed the enhancing abilities of 5-HT synthesis. The treatment remarkably enhanced the 5-HT synthesis by upregulation of Trp concentration and Trp hydroxylase activation. In addition, this study further validated the anti-anxiety effects of whey protein hydrolysate with a high Trp index in animal and the experimental results were consistent with those reported in previous studies. Our results showed that β-lactoglobulin Trp peptides ingestion has a significant anti-anxiety effect as evidenced by the increasing Trp concentration, TPH activation and 5-HT level compared to the control group, with the VAGTW being the more effective.

Comparison of the Protective Effects of Casein Hydrolysate Containing Tyr-Pro-Val-Glu-Pro-Phe and Casein on the Behaviors and Peripheral and Brain Functions in Mice with Chronic-Stress-Induced Anxiety and Insomnia

“…The potential vital structure Tyr at the N-terminus was important for the sleep-enhancing effects of YPVEPF and YPVEP, as we previously proved . Zhu et al identified three Trp-containing peptides from β-lactoglobulin to exert anxiolytic effects . It is also reported that the presence of hydrophobic amino acids Trp and Tyr at the N-terminus of many peptides might be related to the protection of neurotransmitters and cytokines in the brain .…”

“…25 Zhu et al identified three Trp-containing peptides from β-lactoglobulin to exert anxiolytic effects. 58 It is also reported that the presence of hydrophobic amino acids Trp and Tyr at the N-terminus of many peptides might be related to the protection of neurotransmitters and cytokines in the brain. 3 This indicated that the presence of Tyr at the N-terminus and Trp seemed to be important to exert sleepenhancing effects.…”