A novel dipeptide derived from porcine liver hydrolysate induces recovery from physical fatigue in a mouse model
Osamu Nakagawasai, Kotaro Yamada, Wakana Sakuma, Kohei Takahashi, Takayo Odaira, Ryota Yamagata, Wataru Nemoto, Akika Ejima, Kenji Sato, Koichi Tan‐No
Abstract
The present study was conducted to identify anti-fatigue peptides in porcine liver hydrolysate (LH) and to evaluate their effects. Peptides in LH were fractionated into hydrophilic and hydrophobic fractions and further into peptides with amino groups (Pep-NH2) and pyroglutamyl peptide fractions (pE). Low dose of hydrophobic Pep-NH2 fraction reversed the decrease in locomotor activity after forced walking in a mouse model upon intraperitoneal (i.p.) administration. The anti-fatigue effects of i.p. injection of Asp-Val, Asp-Leu, and Asp-Phe with α and β peptide bonds and D- and L- asparatyl residue, which appeared in blood after oral administration of LH, were examined. In particular, Asp-Leu (Lβ), Asp-Phe (Dα), and Asp-Phe (Lα) exerted anti-fatigue effects at a low concentration (0.03 mg/kg). We found that Asp-Phe (Lα), but not other dipeptides, activated adenosine monophosphate-activated protein kinase (AMPK) in the liver, indicating that Asp-Phe (Lα) could induce recovery from fatigue via AMPK activation.