View : 5 Download: 0

Anti-inflammatory mechanism of galangin in lipopolysaccharide-stimulated microglia: Critical role of PPAR-γ signaling pathway

Title
Anti-inflammatory mechanism of galangin in lipopolysaccharide-stimulated microglia: Critical role of PPAR-γ signaling pathway
Authors
Choi M.-J.Lee E.-J.Park J.-S.Kim S.-N.Park E.-M.Kim H.-S.
Ewha Authors
김희선박은미
SCOPUS Author ID
김희선scopus; 박은미scopus
Issue Date
2017
Journal Title
Biochemical Pharmacology
ISSN
0006-2952JCR Link
Citation
vol. 144, pp. 120 - 131
Keywords
GalanginNeuroinflammationNF-κBNrf2/CREB signalingPPAR-γ
Publisher
Elsevier Inc.
Indexed
SCI; SCIE; SCOPUS WOS scopus
Abstract
Since microglia-associated neuroinflammation plays a pivotal role in the progression of neurodegenerative diseases, controlling microglial activation has been suggested as a potential therapeutic strategy. Here, we investigated the anti-inflammatory effects of galangin (3,5,7-trihydroxyflavone) in microglia and analyzed the underlying molecular mechanisms. Galangin inhibited the expression of inducible nitric oxide synthase (iNOS) and pro-inflammatory cytokines and enhanced the expression of anti-inflammatory interleukin (IL)-10 in lipopolysaccharide (LPS)-stimulated BV2 microglia. Galangin also suppressed microglial activation and the expression of pro-inflammatory markers in LPS-injected mouse brains. The results of mechanistic studies have shown that galangin inhibited LPS-induced phosphorylation of p38 mitogen activated protein kinase (MAPK), c-Jun N-terminal kinase (JNK), phosphatidylinositol 3-kinase (PI3K)/Akt, and nuclear factor (NF)-κB activity. On the contrary, galangin increased the activity of transcription factors, such as nuclear factor-E2-related factor 2 (Nrf2), cAMP response element-binding protein (CREB), and peroxisome proliferator-activated receptor (PPAR)-γ, known to play an anti-inflammatory role. In addition, galangin showed antioxidant effects by suppressing the expression of NADPH oxidase subunits p47phox and gp91phox, and by enhancing hemeoxygenase-1. We then investigated whether PPAR-γ was involved in the anti-inflammatory function of galangin. Pretreatment with a PPAR-γ antagonist or siRNA significantly blocked galangin-mediated upregulation of IL-10 and attenuated the inhibition of tumor necrosis factor (TNF)-α, nitric oxide (NO), and IL-6 in LPS-stimulated microglia. Moreover, the PPAR-γ antagonist reversed the effects of galangin on NF-κB, Nrf2, and CREB. Altogether, our data suggest that PPAR-γ plays a key role in mediating the anti-inflammatory effects of galangin by modulating the NF-κB and Nrf2/CREB signaling pathways. © 2017 Elsevier Inc.
DOI
10.1016/j.bcp.2017.07.021
Appears in Collections:
의학전문대학원 > 의학과 > Journal papers
Files in This Item:
There are no files associated with this item.


qrcode

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.

BROWSE