title: The collagen derived dipeptide hydroxyprolyl-glycine promotes C2C12 myoblast differentiation and myotube hypertrophy.
abstract: The majority of studies on possible roles for collagen hydrolysates in human health have focused on their effects on bone and skin. Hydroxyprolyl-glycine (Hyp-Gly) was recently identified as a novel collagen hydrolysate-derived dipeptide in human blood. However, any possible health benefits of Hyp-Gly remain unclear. Here, we report the effects of Hyp-Gly on differentiation and hypertrophy of murine skeletal muscle C2C12 cells. Hyp-Gly increased the fusion index, the myotube size, and the expression of the myotube-specific myosin heavy chain (MyHC) and tropomyosin structural proteins. Hyp-Gly increased the phosphorylation of Akt, mTOR, and p70S6K in myoblasts, whereas the phosphatidylinositol 3-kinase (PI3K) inhibitor LY294002 inhibited their phosphorylation by Hyp-Gly. LY294002 and the mammalian target of rapamycin (mTOR) inhibitor rapamycin repressed the enhancing effects of Hyp-Gly on MyHC and tropomyosin expression. The peptide/histidine transporter 1 (PHT1) was highly expressed in both myoblasts and myotubes, and co-administration of histidine inhibited Hyp-Gly-induced phosphorylation of p70S6K in myoblasts and myotubes. These results indicate that Hyp-Gly can induce myogenic differentiation and myotube hypertrophy and suggest that Hyp-Gly promotes myogenic differentiation by activating the PI3K/Akt/mTOR signaling pathway, perhaps depending on PHT1 for entry into cells.
authors.affiliation: Division of Applied Life Sciences, Graduate School of Life and Environmental Sciences, Osaka Prefecture University, 1-1 Gakuen-cho, Naka-ku, Sakai, Osaka 5998531, Japan.
authors.forename: Tomoya
authors.initials: T
authors.lastname: Kitakaze
authors.affiliation: Division of Applied Life Sciences, Graduate School of Life and Environmental Sciences, Osaka Prefecture University, 1-1 Gakuen-cho, Naka-ku, Sakai, Osaka 5998531, Japan.
authors.forename: Tomotaka
authors.initials: T
authors.lastname: Sakamoto
authors.affiliation: Division of Applied Life Sciences, Graduate School of Life and Environmental Sciences, Osaka Prefecture University, 1-1 Gakuen-cho, Naka-ku, Sakai, Osaka 5998531, Japan.
authors.forename: Takehiro
authors.initials: T
authors.lastname: Kitano
authors.affiliation: Nitta Gelatin Inc., Peptide Division, 2-22 Futamata, Yao, Osaka, 5810024, Japan.
authors.forename: Naoki
authors.initials: N
authors.lastname: Inoue
authors.affiliation: Nitta Gelatin Inc., Peptide Division, 2-22 Futamata, Yao, Osaka, 5810024, Japan.
authors.forename: Fumihito
authors.initials: F
authors.lastname: Sugihara
authors.affiliation: Division of Applied Life Sciences, Graduate School of Life and Environmental Sciences, Osaka Prefecture University, 1-1 Gakuen-cho, Naka-ku, Sakai, Osaka 5998531, Japan.
authors.forename: Naoki
authors.initials: N
authors.lastname: Harada
authors.affiliation: Division of Applied Life Sciences, Graduate School of Life and Environmental Sciences, Osaka Prefecture University, 1-1 Gakuen-cho, Naka-ku, Sakai, Osaka 5998531, Japan. Electronic address: yamaji@biochem.osakafu-u.ac.jp.
authors.forename: Ryoichi
authors.initials: R
authors.lastname: Yamaji
mesh_terms: D000818:Animals; D002454:Cell Differentiation / Q000187:drug effects*; D048429:Cell Size / Q000187:drug effects; D003094:Collagen / Q000494:pharmacology*; D004151:Dipeptides / Q000494:pharmacology*; D006639:Histidine / Q000494:pharmacology; D006984:Hypertrophy; D008297:Male; D026901:Membrane Transport Proteins / Q000378:metabolism; D051379:Mice; D018485:Muscle Fibers, Skeletal / Q000187:drug effects / Q000378:metabolism / Q000473:pathology*; D032446:Myoblasts / Q000166:cytology* / Q000187:drug effects / Q000378:metabolism; D018995:Myosin Heavy Chains / Q000378:metabolism; D019869:Phosphatidylinositol 3-Kinases / Q000378:metabolism; D010766:Phosphorylation; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism; D038762:Ribosomal Protein S6 Kinases, 70-kDa / Q000378:metabolism; D015398:Signal Transduction / Q000187:drug effects; D058570:TOR Serine-Threonine Kinases / Q000378:metabolism; D014335:Tropomyosin / Q000378:metabolism
chemical_list: D003094:Collagen; D004151:Dipeptides; D006639:Histidine; D026901:Membrane Transport Proteins; D018995:Myosin Heavy Chains; D019869:Phosphatidylinositol 3-Kinases; D051057:Proto-Oncogene Proteins c-akt; D038762:Ribosomal Protein S6 Kinases, 70-kDa; D058570:TOR Serine-Threonine Kinases; D014335:Tropomyosin; C554281:Slc15a4 protein, mouse; C575137:hydroxyprolyl-glycine; C043912:peptide permease
keywords: Collagen peptide; Differentiation; Hydroxyprolyl-glycine; Hypertrophy; Myoblast; Myotube