title: Identification of a hepatoprotective peptide in wheat gluten hydrolysate against D-galactosamine-induced acute hepatitis in rats.
abstract: A hepatoprotective peptide, pyroglutamyl leucine (pyroGlu-Leu), was identified in wheat gluten hydrolysate through an in vivo activity-guided fractionation approach based on D-galactosamine-induced acute hepatitis in rats and fractionation of peptides with large-scale preparative ampholine-free isoelectric focusing. The active acidic fraction predominantly consisted of pyroglutamyl peptides and free pyroglutamic acid. Pyroglutamyl peptides were derivatized with phenyl isothiocyanate after removal of a pyroglutamyl residue by pyroglutamate aminopeptidase. The derivatives were purified by reversed-phase HPLC and subjected to sequence analysis. The active fraction contained pyroGlu-Ile, pyroGlu-Leu, pyroGlu-Gln, pyroGlu-Gln-Gln, and free pyroGlu. Ingestion of pyroGlu-Leu at 20 mg/kg body weight significantly decreased serum aspartate and alanine aminotransferases to approximately 30% and 20% of those values of the vehicle group, respectively, which were near the normal levels. Thirty minutes after ingestion of pyroGlu-Leu at 20 mg/kg, the concentration of pyroGlu-Leu in portal blood plasma increased to approximately 2 μM.
authors.affiliation: Division of Applied Life Sciences, Kyoto Prefectural University, Shimogamo, Kyoto 606 8522, Japan. k_sato@kpu.ac.jp
authors.forename: Kenji
authors.initials: K
authors.lastname: Sato
authors.forename: Yukari
authors.initials: Y
authors.lastname: Egashira
authors.forename: Shin
authors.initials: S
authors.lastname: Ono
authors.forename: Satoshi
authors.initials: S
authors.lastname: Mochizuki
authors.forename: Yuki
authors.initials: Y
authors.lastname: Shimmura
authors.forename: Yoshio
authors.initials: Y
authors.lastname: Suzuki
authors.forename: Megumi
authors.initials: M
authors.lastname: Nagata
authors.forename: Kaori
authors.initials: K
authors.lastname: Hashimoto
authors.forename: Tamami
authors.initials: T
authors.lastname: Kiyono
authors.forename: Eun Young
authors.initials: EY
authors.lastname: Park
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Nakamura
authors.forename: Mariko
authors.initials: M
authors.lastname: Itabashi
authors.forename: Yuka
authors.initials: Y
authors.lastname: Sakata
authors.forename: Seigo
authors.initials: S
authors.lastname: Furuta
authors.forename: Hiroo
authors.initials: H
authors.lastname: Sanada
mesh_terms: D000818:Animals; D015415:Biomarkers / Q000097:blood; D004151:Dipeptides / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism / Q000627:therapeutic use*; D004195:Disease Models, Animal; D005688:Galactosamine; D005983:Glutens / Q000378:metabolism*; D006505:Hepatitis / Q000097:blood / Q000517:prevention & control*; D010446:Peptide Fragments / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism / Q000627:therapeutic use; D020011:Protective Agents / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism / Q000627:therapeutic use*; D011492:Protein Hydrolysates / Q000737:chemistry; D011761:Pyrrolidonecarboxylic Acid / Q000031:analogs & derivatives* / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism / Q000627:therapeutic use; D051381:Rats; D014908:Triticum / Q000737:chemistry*
chemical_list: D015415:Biomarkers; D004151:Dipeptides; D010446:Peptide Fragments; D020011:Protective Agents; D011492:Protein Hydrolysates; C041765:pyroglutamylleucine; D005688:Galactosamine; D005983:Glutens; D011761:Pyrrolidonecarboxylic Acid