Photo-oxidative stress by ultraviolet-B radiation and antioxidative defense of eckstolonol in human keratinocytes

Environ Toxicol Pharmacol. 2012 Nov;34(3):926-34. doi: 10.1016/j.etap.2012.08.003. Epub 2012 Aug 30.


Ultraviolet-B (UV-B) irradiation has been known to generate oxidative stress by increasing reactive oxygen species (ROS) in skin cells. Several naturally occurring antioxidant compounds isolated from marine algae are believed to protect against ROS. In this study, we assessed the antioxidative effect of eckstolonol isolated from Ecklonia cava against UV-B-induced ROS in human keratinocytes (HaCaTs). We investigated the effects of photo-oxidative stress by UV-B (50 mJ/cm(2)) and the antioxidative effects of eckstolonol using fluorometry, flow cytometry, microscopy, and cell viability and comet assays. UV-B irradiation decreased cell viability, which was restored in a dose-dependent manner with eckstolonol treatment (0, 5, 50, 100, and 200 μM). Moreover, eckstolonol reduced UV-B-induced ROS, lipid peroxidation, damaged DNA levels, and cell death. These antioxidative effects seem to be due to the enzymatic activities of catalase (CAT) and superoxide dismutase (SOD). Collectively, these results indicate that eckstolonol is capable of protecting keratinocytes from photo-oxidative stress.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antioxidants / pharmacology*
  • Catalase / metabolism
  • Cell Line
  • Cell Survival
  • Comet Assay
  • Dioxanes / pharmacology*
  • Heterocyclic Compounds, 4 or More Rings / pharmacology*
  • Humans
  • Keratinocytes
  • Lipid Peroxidation / drug effects
  • Oxidative Stress / drug effects*
  • Phaeophyta
  • Plant Extracts / pharmacology*
  • Reactive Oxygen Species / metabolism
  • Superoxide Dismutase / metabolism
  • Ultraviolet Rays*


  • Antioxidants
  • Dioxanes
  • Heterocyclic Compounds, 4 or More Rings
  • Plant Extracts
  • Reactive Oxygen Species
  • eckstolonol
  • Catalase
  • Superoxide Dismutase