title: Cinnamon extract promotes type I collagen biosynthesis via activation of IGF-I signaling in human dermal fibroblasts.
abstract: The breakdown of collagenous networks with aging results in hypoactive changes in the skin. Accordingly, reviving stagnant collagen synthesis can help protect dermal homeostasis against aging. We searched for type I collagen biosynthesis-inducing substances in various foods using human dermal fibroblasts and found that cinnamon extract facilitates collagen biosynthesis. Cinnamon extract potently up-regulated both mRNA and protein expression levels of type I collagen without cytotoxicity. We identified cinnamaldehyde as a major active component promoting the expression of collagen by HPLC and NMR analysis. Since insulin-like growth factor-I (IGF-I) is the most potent stimulator of collagen biosynthesis in fibroblasts, we examined the effect of cinnamaldehyde on IGF-I signaling. Treatment with cinnamaldehyde significantly increased the phosphorylation levels of the IGF-I receptor and its downstream signaling molecules such as insulin receptor substrate-1 and Erk1/2 in an IGF-I-independent manner. These results suggested that cinnamon extract is useful in antiaging treatment of skin.
authors.affiliation: Department of Biological Chemistry, Division of Applied Life Science, Graduate School of Life and Environmental Sciences, Osaka Prefecture University, Naka-ku, Sakai, Japan.
authors.forename: Naoko
authors.initials: N
authors.lastname: Takasao
authors.forename: Kentaro
authors.initials: K
authors.lastname: Tsuji-Naito
authors.forename: Seiko
authors.initials: S
authors.lastname: Ishikura
authors.forename: Azusa
authors.initials: A
authors.lastname: Tamura
authors.forename: Mitsugu
authors.initials: M
authors.lastname: Akagawa
mesh_terms: D002460:Cell Line; D002935:Cinnamomum zeylanicum / Q000737:chemistry*; D024042:Collagen Type I / Q000096:biosynthesis* / Q000235:genetics; D005347:Fibroblasts / Q000187:drug effects* / Q000378:metabolism; D006801:Humans; D007334:Insulin-Like Growth Factor I / Q000378:metabolism*; D010936:Plant Extracts / Q000302:isolation & purification / Q000494:pharmacology*; D015398:Signal Transduction / Q000187:drug effects*; D012867:Skin / Q000166:cytology* / Q000378:metabolism
chemical_list: D024042:Collagen Type I; D010936:Plant Extracts; D007334:Insulin-Like Growth Factor I