Anti-oxidant Action and Anti-aging Activity of Phenylpropanoid Compounds

Abstract

Purpose: To investigate the relationship between structure and biological activity of phenylpropanoids, we measured effects of phenylpropanoids on anti-oxidant and anti-inflammatory activity and effect of caffeic acid on wound healing in skin-incised mice. Materials & methods: The cinnamic acid derivaties, C_(6)-C₃ compounds, of Penylpropanoids are used. To investigegate the effects of anti-oxidant activity in cell free system, we measured DPPH radical scavenging assay, xanthine oxidase activity, NBT/xanthine oxidase superoxide scavenging assay. In cell system superoxide production using DHE, H₂O₂ production using DCF-DA and hydroperoxide production using DHR were checked. In order to find out the effects of anti-inflammatory activity, histamine assay, arachidonic acid release and prostaglandin E₂ assay in RBL 2H3 mast cells were measured and NIH 3T3 cell was used for collagen synthesis assay. Balb-c mouse were used to measure collagen assay, MPO assay, PLA₂ activity and lipid peroxidation in vivo system. Result: In DPPH radical scavenging activity, caffeic acid analogues had anti-oxidant activity in a dose-dependent manner, whereas cinnamic acid and coumaric acid did not. Both caffeic acid and chlorogenic acid significantly showed anti-oxidant activity in NBT/XO superoxide anion scavenging assay but others did not. These results suggest that anti-oxidant activity of phenylpropanoid may be related to the hydroxyl residues in aromatic ring. Silica dose-dependently increased the intracellular ROS generation in RBL 2H3 cells. Although phenylpropanoids did not inhibit intracellular superoxide anion generation, both caffeic acid and chlorogenic acid significantly inhibited silica-induced intracellular H₂O₂ and generation hydroxyl radical in RBL 2H3 cells. On the other hand, melittin, an endogenous phospholipase A₂ activator, dose-dependently increased both histamine release and arachidonic acid release. Melittin-induced histamine release were dose-dependently inhibited by caffeic acid and chlorogenic acid, whereas melittin-induced arachidonic acid release was not affected by any of phenylpropanoids. However, melittin-induced prostaglandin E₂ production was significantly inhibited by caffeic, ferulic, sinapinic and chlorogenic acid. These data suggest that inhibitory action of phenylpropanoid on prostaglandin E₂ production may be due to the inhibition of cyclooxygenase rather than phospholipase A₂. In NIH 3T3 fibroblast cells, caffeic acid significantly increased collagen-like polymer synthesis, which suggest that caffeic acid appears to be effective on wound healing. The significant effect of caffeic acid on anti-inflammatory activity and wound healing, such as myeloperoxidase activity, lipid peroxidation, phospholipase A₂ activity and collagen-like polymer synthesis, showed in incised wound mice. Conclusion: From the above results, it is referred that both caffeic acid and chlorogenic acid appear to have potent anti-oxidant and anti-inflammatory activity. In particular, considering the inhibitory activity of caffeic acid among phenylpropanoids in in vitro/cell assay system and in vivo system, it is suggested that the hydroxyl residues of aromatic ring plays an important role in anti-oxidant, anti-inflammatory activity and wound healing effect.