• Environmental Analysis Health and Toxicology
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• v.21 no.3 s.54
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• pp.275-282
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• 2006

In order to get insight into the mechanism of cadmium (Cd)-induced brain injury, we investigated the effects of Cd on the induction of COX-2 in bEnd.3 mouse brain endothelial cells. Cd induced COX-2 expression and $PGE_2$ release, which were attenuated by thiol-reducing antioxidant N-acetylcysteine (NAC) indicating oxidative components might contribute to these events. Indeed, Cd increased cellular reactive oxygen species (ROS) level and DNA binding activity of nuclear factor-kB (NF-kB), an oxidative stress sensitive transcription factor. Cd-induced $PGE_2$ production and COX-2 expression were significantly attenuated by Bay 11 7082, a specific inhibitor of NF-kB and by SB203580, a specific inhibitor of p38 mitogen activated protein kinase (MAPK). These data suggest that Cd induces COX-2 expression through activation of NF-kB and p38 MAPK, the oxidative stress-sensitive signaling molecules, in brain endothelial cells.

• Journal of Life Science
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• v.21 no.5
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• pp.664-670
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• 2011

Oxidative stress results in sustained release of heat shock protein 90 (HSP90) from vascular smooth muscle cells (VSMCs). We investigated whether extracellular HSP90 predisposed VSMCs to pro-inflammatory phenotype. Exposure of human aortic smooth muscle cells to HSP90 not only significantly enhanced CXCL10 secretion but also increased CXCL10 transcription. HSP90-mediated CXCL10 secretion was attenuated by OxPAPC, a TLR-2/4 inhibitor, and curcumin, a TLR-4 dimerization inhibitor. Inhibitors of diphenyleneiodium chloride and the Akt pathway also attenuated CXCL10 secretion in response to HSP90. The gene delivery of I${\kappa}$B using recombinant adenoviruses and treatment with resveratrol, which inhibit NF-${\kappa}$B activity, significantly attenuated HSP90-induced CXCL10 secretion from VSMCs. We propose that extracellular HSP90 contributes to an inflammatory reaction in the stressed vasculature by inducing CXCL10 expression of VSMCs, and that TLR-4, Akt, and NF-${\kappa}$B play active roles in the process.

• The Journal of Korean Medicine
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• v.29 no.1
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• pp.47-59
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• 2008

Objective : Anti-inflammatory effects of the extract of Lycii Fructus on lipopolysaccharide (LPS)-induced inflammation in RAW 264.7 macrophage cells were investigated. Method : In order to assess the cytotoxic effect of Lycii Fructus on the raw 264.7 macrophages 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT) assay was performed. Reverse transcription-polymerase chain reaction(RT-PCR) analysis of the mRNA levels of tumor necrosis factor-$\alpha$(TNF-$\alpha$) and inducible nitric oxide synthase(iNOS) was performed in order to provide an estimate of the relative level of expression of these genes. The protein level of the inhibitor of nuclear factor-${\kappa}B(I{\kappa}B)$ and nuclear factor-${\kappa}B$(NF-${\kappa}B$) activity was investigated by Western blot assay. NO production was investigated by NO detection. Result : Lycii Fructus suppressed NO production by inhibiting the LPS-induced expressions of iNOS and TNF-$^-\alpha$ mRNA and iNOS protein in RAW 264.7 macrophage cells. Also, Lycii Fructus suppressed activation of NF-${\kappa}B$ in the nucleus. Conclusion : These results show that the extract of Lycii Fructus has anti-inflammatory effect probably by suppressing iNOS expressions through the down-regulation of NF-${\kappa}B$ binding activity.

• BMB Reports
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• v.47 no.1
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• pp.45-50
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• 2014

Aspirin has been demonstrated to be effective in inhibiting COX-2 and $PGE_2$ in Alveolar macrophages (AMs). However, the mechanisms have not been fully understood. In the present study, we found that pretreatment with aspirin inhibited LPS-induced COX-2 and$PGE_2$ upregulation, $I{\kappa}B{\alpha}$ degradation, NF-${\kappa}B$ activation and the increase of PKC activity, but elevated LPS-induced the decrease of PTP activity. The PKC inhibitor calphostin C dramatically reduced the COX-2 mRNA and $PGE_2$ levels, but the PTP inhibitor peroxovanadium (POV) significantly increased the COX-2 mRNA and$PGE_2$ levels. Furthermore, the PTP inhibitor mitigated the inhibitory effect of aspirin on COX-2 and$PGE_2$ upregulation and NF-${\kappa}B$ activation, whereas the PKC inhibitor enhanced the inhibitory effects of aspirin on the production of COX-2 and$PGE_2$. Our data indicate a novel mechanism by which aspirin acts as a potent anti-inflammatory agent in alveolus macrophages and ALI.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.11
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• pp.4539-4543
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• 2014

Since the epigenetic alteration in tumor cells can be reversed by the dietary polyphenol quercetin (Q) or butyrate (B) with chemopreventive activity, suggesting that Q or B can be used for chemopreventive as well as therapeutic agent against tumors. In this study the polyphenol flavonoid quercetin (Q) or sodium butyrate (B) suppressed human esophageal 9706 cancer cell growth in dose dependent manner, and Q combined with B (Q+B) could further inhibit Eca9706 cell proliferation than that induced by Q or B alone, compared with untreated control group (C) in MTT assay. The reverse expressions of global DNMT1, $NF-{\kappa}Bp65$, HDAC1 and Cyclin D1 were down-regulated, while expressions of caspase-3 and $p16INK4{\alpha}$ were up-regulated, compared with the C group in immunoblotting; the down-regulated HDAC1-IR (-immunoreactivity) with nuclear translocation, and up-regulated E-cadherin-IR demonstrated in immunocytochemistry treated by Q or B, and Q+B also displayed further negatively and positively modulated effects compared with C group. The order of methylation specific (MS) PCR of $p16INK4{\alpha}$: C>B/Q>Q+B group, while the order of E-cadherin expression level was contrary, Q+B>Q/B>C group. Thus, Q/B, especially Q+B display reverse effect targeting both altered DNA methylation and histone acetylation, acting as histone deacetylase inhibitor mediated via epigenetic-$NF-{\kappa}B$ cascade signaling.

• Nutrition Research and Practice
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• v.14 no.6
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• pp.593-605
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• 2020

BACKGROUND/OBJECTIVES: Alzheimer's disease is common age-related neurodegenerative condition characterized by amyloid beta (Aβ) accumulation that leads cognitive impairment. In the present study, we investigated the protective effect of paeoniflorin (PF) against Aβ-induced neuroinflammation and the underlying mechanism in C6 glial cells. MATERIALS/METHODS: C6 glial cells were treated with PF and Aβ_25-35, and cell viability, nitric oxide (NO) production, and pro-inflammatory cytokine release were measured. Furthermore, the mechanism underlying the effect of PF on inflammatory responses and Aβ degradation was determined by Western blot. RESULTS: Aβ_25-35 significantly reduced cell viability, but this reduction was prevented by the pretreatment with PF. In addition, PF significantly inhibited Aβ_25-35-induced NO production in C6 glial cells. The secretion of interleukin (IL)-6, IL-1β, and tumor necrosis factor-alpha was also significantly reduced by PF. Further mechanistic studies indicated that PF suppressed the production of these pro-inflammatory cytokines by regulating the nuclear factor-kappa B (NF-κB) pathway. The protein levels of inducible NO synthase and cyclooxygenase-2 were downregulated and phosphorylation of NF-κB was blocked by PF. However, PF elevated the protein expression of inhibitor kappa B-alpha and those of Aβ degrading enzymes, insulin degrading enzyme and neprilysin. CONCLUSIONS: These findings indicate that PF exerts protective effects against Aβ-mediated neuroinflammation by inhibiting NF-κB signaling, and these effects were associated with the enhanced activity of Aβ degradation enzymes.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.7
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• pp.2909-2914
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• 2015

Objective: To investigate the protective effect of quercetin on radiation induced lung injury (RILI) and related mechanisms. Materials and Methods: Mice treated with radiation and/or quercetin were sacrificed at 1-8 weeks after irradiation under anesthesia. Lung tissues were collected for histological examination. Immunohistochemistry (IHC) and Western blotting were performed to detect the protein expression of nuclear factor-${\kappa}B$ ($NF-{\kappa}B$) and Mitogen-activated protein kinases (MAPK) pathway. Results: Hematoxylin and eosin (HE) staining showed that radiation controls displayed more severe lung damage than quercetin groups, either high or low dose. Results of IHC and Western blotting demonstrated the expression level of $NF-{\kappa}B$ to be decreased and that of an inhibitor of $NF-{\kappa}B$ ($I{\kappa}b-{\alpha}$) to be increased by the quercetin intervention compared with the radiation control group. Numbers of JNK/SAPK, p38 and p44/p42 positive inflammatory cells were decreased in the radiation+quercetin injection group (P<0.05). Conclusions: Quercetin may play a radio-protective role in mice lung via suppression of $NF-{\kappa}B$ and MAPK pathways.

• The Korean Journal of Pain
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• v.34 no.1
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• pp.47-57
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• 2021

Background: Lumbar disc herniation (LDH) is a common cause of radicular pain, but the mechanism is not clear. In this study, we investigated the engagement of toll-like receptor 4 (TLR4) and the nuclear factor-kappa B (NF-κB) in radicular pain and its possible mechanisms. Methods: An LDH model was induced by autologous nucleus pulposus (NP) implantation, which was obtained from coccygeal vertebra, then relocated in the lumbar 4/5 spinal nerve roots of rats. Mechanical and thermal pain behaviors were assessed by using von Frey filaments and hotplate test respectively. The protein level of TLR4 and phosphorylated-p65 (p-p65) was evaluated by western blotting analysis and immunofluorescence staining. Spinal microglia activation was evaluated by immunofluorescence staining of specific relevant markers. The expression of proand anti-inflammatory cytokines in the spinal dorsal horn was measured by enzyme linked immunosorbent assay. Results: Spinal expression of TLR4 and p-NF-κB (p-p65) was significantly increased after NP implantation, lasting up to 14 days. TLR4 was mainly expressed in spinal microglia, but not astrocytes or neurons. TLR4 antagonist TAK242 decreased spinal expression of p-p65. TAK242 or NF-κB inhibitor pyrrolidinedithiocarbamic acid alleviated mechanical and thermal pain behaviors, inhibited spinal microglia activation, moderated spinal inflammatory response manifested by decreasing interleukin (IL)-1β, IL-6, tumor necrosis factor-α expression and increasing IL-10 expression in the spinal dorsal horn. Conclusions: The study revealed that TLR4/NF-κB pathway participated in radicular pain by encouraging spinal microglia activation and inflammatory response.

• BMB Reports
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• v.49 no.3
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• pp.185-190
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• 2016

Crotamine is a peptide toxin found in the venom of the rattlesnake Crotalus durissus terrificus and has antiproliferative, antimicrobial, and antifungal activities. Herein, we show that crotamine dose-dependently induced macrophage phagocytic and cytostatic activity by the induction of nitric oxide (NO) and tumor necrosis factor-alpha (TNF-α). Moreover, the crotamineinduced expression of iNOS and TNF-α is mediated through the phosphorylation of p38 and the NF-κB signaling cascade in macrophages. Notably, pretreatment with SB203580 (a p38-specific inhibitor) or BAY 11-7082 (an NF-κB inhibitor) inhibited crotamine-induced NO production and macrophage phagocytic and cytotoxic activity. Our results show for the first time that crotamine stimulates macrophage phagocytic and cytostatic activity by induction of NO and TNF-α via the p38 and NF-κB signaling pathways and suggest that crotamine may be a useful therapeutic agent for the treatment of inflammatory disease.

• The Journal of Korean Medicine
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• v.23 no.1
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• pp.50-60
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• 2002

Objectives: Sunghyangjunggisan (SHJS) is a commonly prescribed drug with a wide neuropharmacological spectrum. The water extracts of SHJS were found to be protective against neurotoxicity elicited by deprivation of serum and glucose. Methods: The morphological examination and Hoechst staining of nucleus also clearly showed that the extracts attenuated the cell shrinkage, membrane blebbing, representing typical neuronal apoptotic phenomena and nucleosome-sized fragmentation under the microscope in PC 12 rat pheochromocytoma cells. Results: Activation of protein kinase A (PKA) with dibutyl-cAMP and forskolin also protected during glucose deprivation, although it was not additive with the effect provided by phorbol ester. Interestingly, treatment with the protein kinase A inhibitor, KT5720, was not neuroprotective in the presence of SHJS. Electrophoretic mobility shift assays were used to characterize the neuroprotective binding of nuclear proteins to consensus sequences for AP-l, nuclear factor kappa B ($NF-{\kappa}B$) after glucose deprivation. When PC 12 cells are induced to undergo apoptosis by serum deprivation, AP-l and $NF-{\kappa}B$ DNA binding activity transiently increases to a slight degree. This stimulation is blocked by the water extracts of SHJS. The site of action of the drugs appeared to involve specific inhibition of AP-1 and nuclear factor kB binding activity. Conclusions: Taken together, these results suggested the possibility that the extracts of SHJS might provide a neurotrophic-like activity in PC 12 cells.