Identification of a Novel Peptide from β-Casein That Enhances Spatial and Object Recognition Memory in Mice

Abstract

An increase in the aging population has spurred recent efforts to identify diet and lifestyle changes that help prevent cognitive decline. Several epidemiological investigations and clinical studies have indicated that consuming fermented dairy products prevents cognitive decline. Some peptides from whey including β-lactolin improve memory impairment; the intake of Camembert cheese has been shown to prevent Alzheimer’s in mouse models. To elucidate the molecular mechanisms underlying these preventive effects, we screened peptides from digested casein protein for their ability to improve spatial memory in a scopolamine-induced amnesia mouse model. Administration of KEMPFP­KYPVEP peptide from β-casein at 0.5 mg/kg (54.8 ± 2.5) and 2 mg/kg (57.9 ± 3.7) improved memory impairment in the amnesia mice in comparison with control (44.9 ± 3.4; p = 0.031 and p = 0.042, respectively) and increased dopamine (5.9 ± 3.8 [control] and 12.4 ± 6.2 [KEMPFP­KYPVEP peptide]) and norepinephrine (7.7 ± 0.8 [control] and 9.9 ± 2.0 [KEMPFP­KYPVEP peptide]) levels in the frontal cortex (p = 0.039 and p = 0.031, respectively). Collectively, our findings suggest that peptides in fermented dairy products prevent cognitive decline and support previously reported observations.

Walnut-Derived Peptide Activates PINK1 via the NRF2/KEAP1/HO-1 Pathway, Promotes Mitophagy, and Alleviates Learning and Memory Impairments in a Mice Model

“…Meanwhile, the control, positive, and memory impairment model groups were administered equal volumes of 0.9% normal saline. At 6 weeks, all of the groups were injected with scopolamine solution (1 mg/kg bw) to induce the amnesia mouse model except for the control group, , and the positive group was administered piracetam solution (400 mg/kg bw). The behavioral test was carried out 30 min later by the WMT-100 Morris water maze video analysis system (Chengdu Taimeng Software Co., Ltd., Chengdu, China).…”

The Lacto-Tetrapeptide Gly–Thr–Trp–Tyr, β-Lactolin, Improves Spatial Memory Functions via Dopamine Release and D1 Receptor Activation in the Hippocampus

“…β-Lactoglobulin, a major protein of whey, is rich in WY sequences, and digestion of whey effectively releases β-lactolin, along with other peptide containing WY sequences. In addition, we recently identified another novel bioactive peptide from β-casein that enhances memory functions [6]. Milk proteins including whey and casein would be effective source of bioactive peptides.…”

“…In the process of identifying the ingredients responsible for our previous findings, we screened bioactive peptides from digested β-casein and found KEMPFPKYPVEP peptides, which improve memory function in mice [6]. We further determined the tryptophan–tyrosine (WY) sequence-containing peptides that were abundant in Camembert cheese, including a lacto-tetrapeptide of glycine–threonine–tryptophan–tyrosine (GTWY) and β-lactolin, from β-lactoglobulin in whey digestion, and found that administrating these peptides improved hippocampus-dependent memory functions in mice [7].…”

Dihydromyricetin Improves Cognitive Impairments in d‐Galactose‐Induced Aging Mice through Regulating Oxidative Stress and Inhibition of Acetylcholinesterase

“…The test was based on Ano's method with slight modification. [ 54 ] The NORT assay consisted of training phase and testing phase. In training phase, two identical objects (A and A′, blocks) were fixed opposite each other at the end of a black acrylic box (40 cm × 30 cm × 20 cm).…”