Hepatoprotective constituents of the edible brown alga Ecklonia stolonifera on tacrine-induced cytotoxicity in Hep G2 cells

Arch Pharm Res. 2005 Dec;28(12):1376-80. doi: 10.1007/BF02977904.

Abstract

In this study, ethanolic extracts from 18 seaweed variants were assessed for hepatoprotective activity against tacrine-induced cytotoxicity in Hep G2 cells. Only one of these, Ecklonia stolonifera Okamura (Laminariaceae), a member of the brown algae, exhibited promising hepatoprotective activity. Bioassay-guided fractionation of the active ethyl acetate (EtOAc) soluble fraction obtained from the ethanolic extract of E. stolonifera, resulted in the isolation of several phlorotannins [phloroglucinol (1), eckstolonol (2), eckol (3), phlorofucofuroeckol A (4), and dieckol (5)]. Compounds 2 and 4 were determined to protect Hep G2 cells against the cytotoxic effects of tacrine, with EC50 values of 62.0 and 79.2 microg/mL, respectively. Silybin, a well characterized hepatoprotective agent, was used as a positive control, and exhibited an EC50 value of 50.0 microg/mL. It has been suggested that the phlorotannins derived from marine brown algae might prove useful sources in the development of novel hepatoprotective agents.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Benzofurans / chemistry
  • Benzofurans / isolation & purification
  • Benzofurans / pharmacology
  • Cell Line, Tumor
  • Cell Survival / drug effects
  • Chemical Fractionation / methods
  • Dioxanes / chemistry
  • Dioxanes / isolation & purification
  • Dioxanes / pharmacology
  • Dioxins / chemistry
  • Dioxins / isolation & purification
  • Dioxins / pharmacology
  • Ethanol / chemistry
  • Heterocyclic Compounds, 4 or More Rings / chemistry
  • Heterocyclic Compounds, 4 or More Rings / isolation & purification
  • Heterocyclic Compounds, 4 or More Rings / pharmacology
  • Humans
  • Inhibitory Concentration 50
  • Liver / drug effects*
  • Liver / pathology
  • Phaeophyceae / chemistry*
  • Phloroglucinol / chemistry
  • Phloroglucinol / pharmacology
  • Protective Agents / chemistry
  • Protective Agents / isolation & purification
  • Protective Agents / pharmacology*
  • Silybin
  • Silymarin
  • Tacrine / pharmacology
  • Tannins / chemistry
  • Tannins / isolation & purification
  • Tannins / pharmacology

Substances

  • Benzofurans
  • Dioxanes
  • Dioxins
  • Heterocyclic Compounds, 4 or More Rings
  • Protective Agents
  • Silymarin
  • Tannins
  • eckstolonol
  • phlorofucofuroeckol A
  • Ethanol
  • Silybin
  • Tacrine
  • Phloroglucinol