Tetrandrine suppresses LPS-induced astrocyte activation via modulating IKKs-IkappaBalpha-NF-kappaB signaling pathway

Mol Cell Biochem. 2008 Aug;315(1-2):41-9. doi: 10.1007/s11010-008-9787-4. Epub 2008 May 23.

Abstract

Astrocyte activation has been implicated in the pathogenesis of many neurological diseases. These reactive astrocytes are capable of producing a variety of proinflammatory mediators and potentially neurotoxic compounds, such as nitric oxide (NO), tumor necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6) and interleukin-1beta (IL-1beta). In this study, we examined the suppressive effects of Tetrandrine (TET) on astrocyte activation induced by lipopolysaccharide (LPS) in vitro. We found that TET decreased the release of NO, TNF-alpha, IL-6 and IL-1beta in LPS-activated astrocytes. Also mRNA expression levels of inducible nitric oxide synthase (iNOS), macrophage inflammatory protein-1alpha (MIP-1alpha) and vascular cell adhesion molecule-1 (VCAM-1) were inhibited in TET pretreated astrocytes. Such suppressive effects might be resulted from the inhibition of nuclear factor kappa B (NF-kappaB) activation through downregulating IkappaB kinases (IKKs) phosphoration, which decreased inhibitor of nuclear factor-kappaB-alpha (IkappaBalpha) phosphoration and degradation. Our results suggest that TET acted to regulate astrocyte activation through inhibiting IKKs-IkappaBalpha-NF-kappaB signaling pathway.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Astrocytes / drug effects*
  • Astrocytes / enzymology*
  • Benzylisoquinolines / pharmacology*
  • Chemokine CCL3 / genetics
  • Chemokine CCL3 / metabolism
  • Gene Expression Regulation / drug effects
  • I-kappa B Kinase / antagonists & inhibitors
  • I-kappa B Kinase / metabolism*
  • I-kappa B Proteins / metabolism*
  • Interleukin-1beta / metabolism
  • Interleukin-6 / metabolism
  • Lipopolysaccharides / pharmacology*
  • NF-KappaB Inhibitor alpha
  • NF-kappa B / metabolism*
  • Nitric Oxide / metabolism
  • Nitric Oxide Synthase Type II / genetics
  • Nitric Oxide Synthase Type II / metabolism
  • Phosphorylation / drug effects
  • Protein Processing, Post-Translational / drug effects
  • RNA, Messenger / genetics
  • RNA, Messenger / metabolism
  • Rats
  • Rats, Sprague-Dawley
  • Signal Transduction / drug effects
  • Tumor Necrosis Factor-alpha / metabolism
  • Vascular Cell Adhesion Molecule-1 / genetics
  • Vascular Cell Adhesion Molecule-1 / metabolism

Substances

  • Benzylisoquinolines
  • Chemokine CCL3
  • I-kappa B Proteins
  • Interleukin-1beta
  • Interleukin-6
  • Lipopolysaccharides
  • NF-kappa B
  • Nfkbia protein, rat
  • RNA, Messenger
  • Tumor Necrosis Factor-alpha
  • Vascular Cell Adhesion Molecule-1
  • NF-KappaB Inhibitor alpha
  • tetrandrine
  • Nitric Oxide
  • Nitric Oxide Synthase Type II
  • I-kappa B Kinase