skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Inhibition of lipopolysaccharide-stimulated NO production by crotafuran B in RAW 264.7 macrophages involves the blockade of NF-{kappa}B activation through the increase in I{kappa}B{alpha} synthesis

Abstract

Crotafuran B, a natural pterocarpanoid isolated from Crotalaria pallida, inhibited the lipopolysaccharide (LPS)-stimulated nitric oxide (NO) production (IC{sub 5} 16.4 {+-} 0.7 {mu}M) and inducible nitric oxide synthase (iNOS) protein and mRNA expression (IC{sub 5} 11.5 {+-} 0.6 {mu}M and 11.8 {+-} 2.2 {mu}M, respectively), but not via its cytotoxicity or the inhibition of iNOS enzyme activity, in RAW 264.7 macrophages. Crotafuran B also reduced the iNOS promoter activity (IC{sub 5} 13.4 {+-} 0.1 {mu}M) in piNOS-LUC-transfected cells. Crotafuran B treatment inhibited the p65 nuclear translocation and the nuclear factor-{kappa}B (NF-{kappa}B) DNA binding activity in LPS-activated macrophages. Crotafuran B also reduced the NF-{kappa}B transcriptional activity in pNF-{kappa}B-LUC-transfected cells. Crotafuran B had no effect on the LPS-induced phosphorylation of inhibitory {kappa}B{alpha} (I{kappa}B{alpha}), but enhanced the cellular level of I{kappa}B{alpha} that rebounded to the basal levels and increased the I{kappa}B{alpha} mRNA expression. These results indicate that the crotafuran B inhibition of NO production involves a decrease in the iNOS gene expression via the inhibition of NF-{kappa}B activation through the increase in I{kappa}B{alpha} synthesis.

Authors:
 [1];  [2];  [1];  [1];  [3];  [4];  [3];  [5];  [6]
  1. Graduate Institute of Pharmaceutical Chemistry, China Medical University, Taichung, Taiwan (China)
  2. Department of Education and Research, Taichung Veterans General Hospital, 160, Sec. 3, Chung Kang Road, Taichung 407, Taiwan (China)
  3. School of Pharmacy, Kaohsiung Medical University, Kaohsiung, Taiwan (China)
  4. Faculty of Fragrance and Cosmetics, Kaohsiung Medical University, Kaohsiung, Taiwan (China)
  5. Department of Biochemistry, China Medical University, Taichung, Taiwan (China)
  6. Graduate Institute of Pharmaceutical Chemistry, China Medical University, Taichung, Taiwan (China) and Department of Education and Research, Taichung Veterans General Hospital, 160, Sec. 3, Chung Kang Road, Taichung 407, Taiwan (China). E-mail: w1994@vghtc.gov.tw
Publication Date:
OSTI Identifier:
20783407
Resource Type:
Journal Article
Resource Relation:
Journal Name: Toxicology and Applied Pharmacology; Journal Volume: 210; Journal Issue: 1-2; Other Information: DOI: 10.1016/j.taap.2005.07.009; PII: S0041-008X(05)00419-9; Copyright (c) 2005 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
60 APPLIED LIFE SCIENCES; BIOSYNTHESIS; DNA; ENZYME ACTIVITY; INDIUM OXIDES; INHIBITION; MACROPHAGES; NITRIC OXIDE; PHOSPHORYLATION; PROTEINS; TOXICITY; TRANSLOCATION

Citation Formats

Lin, M.-W., Tsao, L.-T., Huang, L.-J., Kuo, S.-C., Weng, J.-R., Ko, H.-H., Lin, C.-N., Lee, M.-R., and Wang, J.-P. Inhibition of lipopolysaccharide-stimulated NO production by crotafuran B in RAW 264.7 macrophages involves the blockade of NF-{kappa}B activation through the increase in I{kappa}B{alpha} synthesis. United States: N. p., 2006. Web. doi:10.1016/j.taap.2005.07.009.
Lin, M.-W., Tsao, L.-T., Huang, L.-J., Kuo, S.-C., Weng, J.-R., Ko, H.-H., Lin, C.-N., Lee, M.-R., & Wang, J.-P. Inhibition of lipopolysaccharide-stimulated NO production by crotafuran B in RAW 264.7 macrophages involves the blockade of NF-{kappa}B activation through the increase in I{kappa}B{alpha} synthesis. United States. doi:10.1016/j.taap.2005.07.009.
Lin, M.-W., Tsao, L.-T., Huang, L.-J., Kuo, S.-C., Weng, J.-R., Ko, H.-H., Lin, C.-N., Lee, M.-R., and Wang, J.-P. Sun . "Inhibition of lipopolysaccharide-stimulated NO production by crotafuran B in RAW 264.7 macrophages involves the blockade of NF-{kappa}B activation through the increase in I{kappa}B{alpha} synthesis". United States. doi:10.1016/j.taap.2005.07.009.
@article{osti_20783407,
title = {Inhibition of lipopolysaccharide-stimulated NO production by crotafuran B in RAW 264.7 macrophages involves the blockade of NF-{kappa}B activation through the increase in I{kappa}B{alpha} synthesis},
author = {Lin, M.-W. and Tsao, L.-T. and Huang, L.-J. and Kuo, S.-C. and Weng, J.-R. and Ko, H.-H. and Lin, C.-N. and Lee, M.-R. and Wang, J.-P.},
abstractNote = {Crotafuran B, a natural pterocarpanoid isolated from Crotalaria pallida, inhibited the lipopolysaccharide (LPS)-stimulated nitric oxide (NO) production (IC{sub 5} 16.4 {+-} 0.7 {mu}M) and inducible nitric oxide synthase (iNOS) protein and mRNA expression (IC{sub 5} 11.5 {+-} 0.6 {mu}M and 11.8 {+-} 2.2 {mu}M, respectively), but not via its cytotoxicity or the inhibition of iNOS enzyme activity, in RAW 264.7 macrophages. Crotafuran B also reduced the iNOS promoter activity (IC{sub 5} 13.4 {+-} 0.1 {mu}M) in piNOS-LUC-transfected cells. Crotafuran B treatment inhibited the p65 nuclear translocation and the nuclear factor-{kappa}B (NF-{kappa}B) DNA binding activity in LPS-activated macrophages. Crotafuran B also reduced the NF-{kappa}B transcriptional activity in pNF-{kappa}B-LUC-transfected cells. Crotafuran B had no effect on the LPS-induced phosphorylation of inhibitory {kappa}B{alpha} (I{kappa}B{alpha}), but enhanced the cellular level of I{kappa}B{alpha} that rebounded to the basal levels and increased the I{kappa}B{alpha} mRNA expression. These results indicate that the crotafuran B inhibition of NO production involves a decrease in the iNOS gene expression via the inhibition of NF-{kappa}B activation through the increase in I{kappa}B{alpha} synthesis.},
doi = {10.1016/j.taap.2005.07.009},
journal = {Toxicology and Applied Pharmacology},
number = 1-2,
volume = 210,
place = {United States},
year = {Sun Jan 15 00:00:00 EST 2006},
month = {Sun Jan 15 00:00:00 EST 2006}
}
  • Inflammation is involved in numerous diseases, including chronic inflammatory diseases and the development of cancer. Many plants possess a variety of biological activities, including antifungal, antibacterial and anti-inflammatory activities. However, our understanding of the anti-inflammatory effects of 6-gingerol is very limited. We used lipopolysaccharide (LPS)-stimulated macrophages as a model of inflammation to investigate the anti-inflammatory effects of 6-gingerol, which contains phenolic structure. We found that 6-gingerol exhibited an anti-inflammatory effect. 6-Gingerol could decrease inducible nitric oxide synthase and TNF-{alpha} expression through suppression of I-{kappa}B{alpha} phosphorylation, NF-{kappa}B nuclear activation and PKC-{alpha} translocation, which in turn inhibits Ca{sup 2+} mobilization and disruptionmore » of mitochondrial membrane potential in LPS-stimulated macrophages. Here, we demonstrate that 6-gingerol acts as an anti-inflammatory agent by blocking NF-{kappa}B and PKC signaling, and may be developed as a useful agent for the chemoprevention of cancer or inflammatory diseases.« less
  • Chebulagic acid (CA), a natural anti-oxidant, showed potent anti-inflammatory effects in LPS-stimulated RAW 264.7, a mouse macrophage cell line. These effects were exerted via inhibition of NO and PGE{sub 2} production and down-regulation of iNOS, COX-2, 5-LOX, TNF-{alpha} and IL-6. CA inhibited NF-{kappa}B activation by LPS, and this was associated with the abrogation of I{kappa}B-{alpha} phosphorylation and subsequent decreases in nuclear p50 and p65 protein levels. Further, the phosphorylation of p38, ERK 1/2 and JNK in LPS-stimulated RAW 264.7 cells was suppressed by CA in a concentration-dependent manner. LPS-induced generation of reactive oxygen species (ROS) was also effectively inhibited bymore » CA. These results suggest that CA exerts anti-inflammatory effects in LPS-stimulated RAW 264.7 macrophages by inhibition of NF-{kappa}B activation and MAP kinase phosphorylation.« less
  • Carabrol, isolated from Carpesium macrocephalum, showed anti-inflammatory potential in LPS-induced RAW 264.7 murine macrophages. In present study, carabrol demonstrated the inhibitory activity on pro-inflammatory cytokines such as IL-1{beta}, IL-6 and TNF-{alpha}. In addition, mRNA and protein levels of iNOS and COX-2 were reduced by carabrol. Molecular analysis revealed that these suppressive effects were correlated with the inactivation of p38 and JNK via inhibition of NF-{kappa}B activation. Immunoblotting showed that carabrol suppressed LPS-induced degradation of I-{kappa}B{alpha} and decreased nuclear translocation of p65. Taken together, these results suggest that carabrol can be a modulator of pro-inflammatory signal transduction pathway in RAW 264.7more » cells.« less
  • Nuclear factor kappa B (NF-κB) is a ubiquitous transcription factor which controls the expression of various genes involved in immune responses. However, it is not clear whether NF-κB activation is critical for phagocytosis when Staphylococcus aureus is the pathogen. Using oligonucleotide microarrays, we investigated whether NF-κB cascade genes are altered in a mouse leukemic monocyte macrophage cell line (RAW 264.7) when the cells were stimulated to activate a host innate immune response against live S. aureus or heat-inactivated S. aureus (HISA). NF-κB cascade genes such as Nfκb1, Nfκbiz, Nfκbie, Rel, Traf1 and Tnfaip3 were up-regulated by all treatments at onemore » hour after incubation. NF-κB play an important role in activating phagocytosis in RAW 264.7 cells infected with S. aureus. Inhibition of NF-κB significantly blocked phagocytosis of fluorescently labeled S. aureus and decreased the expression of NFκB1, IL1α, IL1β and TLR2 in this cell line. Our results demonstrate that S. aureus may activate the NF-κB pathway and that NF-κB activation is required for phagocytosis of S. aureus by macrophages. - Highlights: • NF-κB cascade genes such as Nfκb1 and Traf1 were up-regulated by heat-inactivated S. aureus. • Inhibition of NF-κB significantly blocked phagocytosis of fluorescently labeled S. aureus. • NF-κB activation is required for phagocytosis of S. aureus by macrophages.« less
  • Induction of type I interferon (IFN-{alpha}/{beta}) is an early antiviral response of the host, and porcine reproductive and respiratory syndrome virus (PRRSV) has been reported to downregulate the IFN response during infection in cells and pigs. We report that the PRRSV nonstructural protein 1{alpha} (Nsp1{alpha}) subunit of Nsp1 is a nuclear-cytoplasmic protein distributed to the nucleus and contains a strong suppressive activity for IFN-{beta} production that is mediated through the retinoic acid-inducible gene I (RIG-I) signaling pathway. Nsp1{alpha} suppressed the activation of nuclear factor (NF)-{kappa}B when stimulated with dsRNA or tumor necrosis factor (TNF)-{alpha}, and NF-{kappa}B suppression was RIG-I-dependent. Themore » suppression of NF-{kappa}B activation was associated with the poor production of IFN-{beta} during PRRSV infection. The C-terminal 14 amino acids of the Nsp1{alpha} subunit were critical in maintaining immunosuppressive activity of Nsp1{alpha} for both IFN-{beta} and NF-{kappa}B, suggesting that the newly identified zinc finger configuration comprising of Met180 may be crucial for inhibitory activities. Nsp1{alpha} inhibited I{kappa}B phosphorylation and as a consequence NF-{kappa}B translocation to the nucleus was blocked, leading to the inhibition of NF-{kappa}B stimulated gene expression. Our results suggest that PRRSV Nsp1{alpha} is a multifunctional nuclear protein participating in the modulation of the host IFN system.« less