Inflammation

, Volume 34, Issue 5, pp 463–470 | Cite as

Baicalin Inhibits TLR2/4 Signaling Pathway in Rat Brain Following Permanent Cerebral Ischemia

  • Xian-kun Tu
  • Wei-zhong Yang
  • Song-sheng Shi
  • Ye Chen
  • Chun-hua Wang
  • Chun-mei Chen
  • Zhen Chen
Article

Abstract

Recent work from our laboratory demonstrated that baicalin attenuates inflammatory reaction and cerebral ischemia injury in rats. Toll-like receptor 2 and 4 (TLR2/4) and the downstream nuclear factor-kappa B (NF-κB) signaling pathway, which mediate the inflammatory reaction, are involved in the pathophysiological processes of cerebral ischemia. In this study, we investigated whether baicalin inhibits TLR2/4 signaling pathway in a rat model of permanent focal cerebral ischemia. Adult Sprague–Dawley rats underwent permanent middle cerebral artery occlusion (MCAO). Baicalin was administered by intraperitoneally injected twice at 2 and 12 h after the onset of ischemia. Cerebral infarct area and infarct volume were measured 24 h after MCAO. Expression of TLR2/4, NF-κB, inducible nitric oxide synthase (iNOS), and cyclooxygenase-2 (COX-2) were determined by RT-PCR or western blot. NO and PGE2 production in rat brain were measured 24 h after MCAO. Serum content of tumor necrosis factor-alpha (TNF-α) and interleukin-1β (IL-1β) were detected by ELISA. Baicalin reduced cerebral infarct area and infarct volume. Baicalin reduced the expression of TLR2/4 and NF-κB, decreased the expression and activity of iNOS and COX-2 in rat brain. Baicalin also attenuated the serum content of TNF-α and IL-1β. Our results suggest that baicalin inhibits the TLR2/4 signaling pathway in cerebral ischemia, which may be a mechanism underlying the baicalin’s neuroprotection.

KEY WORDS

baicalin cerebral ischemia cyclooxygenase-2 inducible nitric oxide synthase inflammation interleukin-1β nuclear factor-kappa B toll-like receptors tumor necrosis factor-α 

Notes

ACKNOWLEDGEMENTS

The Key Laboratory (Neurosurgical Department) Fund from the Affiliated Union Hospital of Fujian Medical University, and the Professor Academic Development Fund of Fujian Medical University (JS0610) supported this work.

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Copyright information

© Springer Science+Business Media, LLC 2010

Authors and Affiliations

  • Xian-kun Tu
    • 1
    • 2
  • Wei-zhong Yang
    • 1
    • 2
  • Song-sheng Shi
    • 1
  • Ye Chen
    • 3
  • Chun-hua Wang
    • 2
  • Chun-mei Chen
    • 1
  • Zhen Chen
    • 1
  1. 1.Department of NeurosurgeryThe Affiliated Union Hospital of Fujian Medical UniversityFuzhouChina
  2. 2.Fujian Neurosurgical Institute29# Xinquan Road, FuzhouFujianChina
  3. 3.Department of AnesthesiologyFujian Provincial HospitalFuzhouChina

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