Antioxidative Activity of the Hydrolytic Enzyme Treated Sorbus commixta Hedl. and its Inhibitory Effect on Matrix Metallopro- teinase- 1 in UV Irradiated Human Dermal Fibroblasts

Abstract

Superoxide radical scavenging activity and DPPH radical scavenging activity were assessed in order to evaluate the antioxidant effect of the Sorbus commixta Hedl. extract (SCoE). SCoE was also treated with several carbohydrate-hydrolytic enzymes that significantly increased the total phenol and flavonoid composition of SCoE. The enzymatically treated SCoE was then assessed for antioxidative activity. The most efficient radical scavenging activity was observed when SCoE was treated with -glucanase. The radical scavenging activity of beta-glucanase-treated SCoE (beta-GSCoE) enhanced the viability of human dermal fibroblasts (HDFs) exposed to ultraviolet (UV) light. The intracellular reactive oxygen species (ROS) scavenging activity of beta-GSCoE was assessed using UVB (20 mJ/cm2)-irradiated HDFs. UVB irradiation increased dichlorofluorescein (DCF) fluorescence, which was measured by a 5-(6-)chloromethyl-2',7'- dichlorodihydrofluorescein diacetate (CM-H2DCFDA). DCF-fluorescence was significantly decreased in the beta-GSCoE-containing culture medium, suggesting that beta-GSCoE scavenges free radicals. The protective effect was further verified by assessing the expression of matrix metalloproteinase-1 (MMP-1) in UVA-irradiated HDFs. The treatment of UVA-irradiated HDFs with beta-GSCoE resulted in a dose-dependent decrease in the expression level of MMP-1 protein and mRNA. These results suggest that beta-GSCoE may mitigate the effects of photoaging in skin by reducing UV-induced adverse skin reactions.