Suppression of tissue necrosis factor-alpha or hydrogen peroxide-activated primary human T lymphocytes by Ginkgo biloba extract through down-regulation of activator protein-1 signal transduction

Phytomedicine. 2008 Mar;15(3):170-6. doi: 10.1016/j.phymed.2007.03.016. Epub 2007 May 3.

Abstract

Purpose: It was unknown whether Ginkgo biloba extract has regulatory effects on human T lymphocytes activated by tissue necrosis factor-alpha (TNF-alpha), which has an important role on the progression of inflammatory atherosclerotic plaques. We evaluated the effects of G. biloba extract on activated human peripheral T lymphocytes, which were isolated from human whole blood.

Methods: The human T lymphocytes were treated with 25-100 microg G. biloba extract for 2h first. Then they were activated by TNF-alpha and H(2)O(2) to investigate the modulatory effects of G. biloba extract on human T lymphocytes. Electrophoretic mobility shift assay, Western blot (Immunoblot) analysis and immunoprecipitation kinase assays were used.

Results: The inhibition of activated human T lymphocyte specifically correlated with the down-regulation of AP-1 DNA-binding activities. G. biloba extract was unique in its ability to inhibit the activation of c-Jun NH2-terminal protein kinase.

Conclusions: G. biloba extract might have its novel therapeutic effects on inflammation-based atherosclerotic diseases.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Anti-Inflammatory Agents / pharmacology*
  • Down-Regulation*
  • Electrophoretic Mobility Shift Assay
  • Ginkgo biloba / chemistry*
  • Humans
  • Hydrogen Peroxide / metabolism
  • JNK Mitogen-Activated Protein Kinases / antagonists & inhibitors*
  • Lymphocyte Activation
  • Plant Extracts / pharmacology*
  • Signal Transduction
  • T-Lymphocytes / drug effects*
  • Transcription Factor AP-1 / physiology*
  • Tumor Necrosis Factor-alpha / metabolism

Substances

  • Anti-Inflammatory Agents
  • Plant Extracts
  • Transcription Factor AP-1
  • Tumor Necrosis Factor-alpha
  • Hydrogen Peroxide
  • JNK Mitogen-Activated Protein Kinases