김(Pyropia yezoensis) peptide에 의한 인체 피부 섬유아세포에서의 콜라겐 합성 촉진 메커니즘

Abstract

Pyropia yezoensis is a marine algae that exhibits anti-oxidative, anti-inflammatory, anti-tumor and anti-aging activities. In this present study, we investigated the effect of P. yezoensis peptide (PYP) on collagen synthesis and the mechanism focusing on the TGF-β/Smad and IGF-1 signal pathways in human dermal fibroblast Hs27 cells. Hs27 cells were incubated in serum-free medium with various concentrations of PYP (250, 500 and 1,000 ng/ml) for 24 h. Using the MTS assay, we found that PYP did not affect cell viability. Moreover, we confirmed that PYP increased type 1 collagen expression using enzyme-linked immunosorbent assay (ELISA), western blot and real-time PCR analysis. In addition, we identified changes in various enzymes as well as the mechanism behind PYP-induced collagen synthesis. PYP decreased MMP-1 protein and mRNA levels and increased TIMP-1 and TIMP-2 protein and mRNA levels. Transforming growth factor-β (TGF-β) plays important roles in regulating cellular processes such as cell growth, differentiation, migration, apoptosis and ECM components. PYP increased TGF-β1 ligand protein and mRNA levels. TGF-β1 induces activation of various intracellular signal pathway including mitogen-activated protein kinases (MAPK) and TGF-β/Smad signal pathway. PYP activated TGF-β/Smad signal pathway, but did not influence into MAPK signal pathway. Furthermore, activated TGF-β/Smad signal pathway by treatment with PYP induced transcription factor specificity protein 1 (Sp1). To investigate effect of TGF-β/Smad signal pathway on PYP-induced collagen synthesis, cells were treated TGFβ-RI inhibitor (10 μM, SB431542) for 2 h. SB431542 reduced the increased COL1A1, COL1A2 and TIMP-1, 2 mRNA expression levels by treatment with PYP, and increased the decreased MMP-1 protein expression level by treatment with PYP. Insullin-like growth factor-1 (IGF-1) regulates cell metabolism, differentiation, growth, survival and ECM component synthesis. PYP increased IGF-1 ligand expression and activated IGF-1 signal pathway including phospatidylinositol 3-kinase (PI3K)/Akt/mammalian target of rapamycin (mTOR)/ribosomal protein S6 kinase beta-1 (p70S6K) signal pathway. These results indicate that PYP promotes collagen synthesis by activating both TGF-β/Smad and IGF-1 signal pathways. So, PYP could be a potential source of functional cosmetic and food materials to have effect of promoting collagen synthesis.