Evaluation of protective effect of cyclodextrin glucanotransferase-treated gastrodia elata blume extract on ultraviolet b-induced premature skin aging

Purpose: To investigate the protective effect of Gastrodia elata Blume (G. elata, GE) and cyclodextrin glucanotransferase (CGTase) enzyme-treated G. elata extract (EGE) against premature skin aging using ultraviolet B (UVB)-exposed normal human dermal fibroblasts (NHDFs). Methods: The extract was characterized by liquid chromatography with tandem mass spectrometry (LC-MS/MS), ultra-high performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC–QToF–MS) and nuclear magnetic resonance spectroscopy (NMR). The expression of matrix metalloproteinases (MMP-1,3), interleukin-6 (IL-6), transforming growth factor (TGF-β1) and procollagen type I was assayed using ELISA kits. Safety evaluation of EGE’s dietary administration and topical application was performed by in vivo acute oral toxicity and local lymph node tests. Results: Lower MMP-1 and IL-6 and higher procollagen type I and TGF-β1 levels were observed after treatment with EGE than with GE, indicating that EGE was more effective than GE in treating UVB-induced photoaging. With respect to phenolic composition, EGE had lower 4-hydroxybenzaldehyde (4-HBA) level and higher α-gastrodin level than GE. In UVB-irradiated NHDFs, α-gastrodin exhibited higher anti-aging activity than 4-HBA and β-gastrodin based on the expression of MMP-1, MMP-3, and procollagen type I. The in vivo data indicate that EGE was safe at concentrations of up to 2000 mg/kg for dietary administration and 0.1 % for topical application. Conclusion: EGE protects UVB-induced photoaged human skin better than GE owing to its higher α-gastrodin content. Thus, EGE may be potentially useful agent in anti-aging cosmetic products.