Abstract
Garlic has long been used as a folk medicine. Numerous studies have demonstrated that a garlic extract and its sulfur-containing compounds inhibited nuclear factor kappa B (NF-κB) activation induced by various receptor agonists including lipopolysaccharide (LPS). Toll-like receptors (TLRs) play a key role in sensing diverse microbial products and inducing innate immune responses. The dimerization of TLR4 is required for the activation of downstream signaling pathways, including NF-κB. Therefore, TLR4 dimerization may be one of the first lines of regulation in activating LPS-induced signaling pathways. We report here biochemical evidence that the ethyl acetate fraction of garlic inhibited the LPS-induced dimerization of TLR4, resulting in the inhibition of NF-κB activation and the expression of cyclooxygenase 2 and inducible nitric oxide synthase. Our results demonstrate for the first time that a garlic extract can directly inhibit the TLRs-mediated signaling pathway at the receptor level. These results shed a new insight into understanding how garlic modulates the immune responses that could modify the risk of many chronic diseases.
Original language | English (US) |
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Pages (from-to) | 368-375 |
Number of pages | 8 |
Journal | Bioscience, Biotechnology and Biochemistry |
Volume | 72 |
Issue number | 2 |
DOIs | |
State | Published - 2008 |
Keywords
- Cyclooxygenase
- Garlic
- Nitric oxide synthase
- Toll-like receptor
ASJC Scopus subject areas
- Bioengineering
- Biotechnology
- Biochemistry
- Biochemistry, Genetics and Molecular Biology(all)
- Chemistry (miscellaneous)
- Applied Microbiology and Biotechnology
- Food Science