• Archives of Pharmacal Research
• /
• v.28 no.3
• /
• pp.297-304
• /
• 2005

Naturally occurring flavonoids are known to modulate various inflammatory and immune processes. Based on structural property, in this study, molecular mechanism of flavonoids in modulating nitric oxide (NO) production and its signaling pathway were investigated using lipopolysaccharide (LPS)-activated RAW264.7 cells. Although flavonol-typed flavonoids (kaempferol and quercetin) more potently scavenged reactivity of nitric oxide ($\cdot$NO) as well as peroxynitrite (ONOO$\kappa$) than isoflavones (genistein and genistin), kaempferol, quercetin and genistein showed a little difference in inhibition of both inducible NO synthase expression and NO production, with IC$_{50}$ values of 13.9, 20.1 and 26.8 $\mu$M. However, there was a striking pattern related to structural feature in modulation of LPS-mediated signaling pathways. Thus, flavonols only inhibited transcription factor AP-1 activation, whereas isoflavones suppressed the DNA binding activation of NF-$\kappa$B and C/EBP$\beta$. Therefore, these data suggest that structural feature may be linked to decide drugs target molecule in LPS-mediated signaling pathways, rather than its potency.

• Journal of Microbiology and Biotechnology
• /
• v.17 no.12
• /
• pp.2042-2045
• /
• 2007

The effect of chitosan oligosaccharide (COS, 1 kDa${\gamma}$, 10 ng/ml IL-$1{\alpha}$, and 25 ng/ml TNF-${\alpha}$) in HT-29 cells. Inducible nitric oxide synthase (iNOS) expression induced by these cytokines was inhibited by COS. COS pretreatment inhibited the invasiveness of cytokines-treated HT-29 cells through Matrigel-coated membrane in a dose-dependent manner. COS also inhibited cytokines-induced matrix metalloproteinase (MMP)-2 activity. This study shows that proinflammatory cytokines induce NO production, iNOS expression, and invasiveness of human colorectal adenocarcinoma HT-29 cells. COS pretreatment inhibited cytokines-mediated NO production, iNOS expression, and invasiveness of HT-29 cells. These results provide sufficient information for the further development of COS as an antitumor metastatic agent for the treatment of colon cancer.

• Biomolecules & Therapeutics
• /
• v.21 no.5
• /
• pp.364-370
• /
• 2013

Resveratrol (trans-3,4'-trihydroxystillbene), a naturally occurring polyphenolic antioxidant found in grapes and red wine, elicits diverse biochemical responses and demonstrates anti-aging, anti-inflammatory, and anti-proliferative effects in several cell types. Previously, resveratrol was shown to regulate differentiation and inflammation in rabbit articular chondrocytes, while the direct production of nitric oxide (NO) in these cells by treatment with the NO donor sodium nitroprusside (SNP) led to apoptosis. In this study, the effect of resveratrol on NO-induced apoptosis in rabbit articular chondrocytes was investigated. Resveratrol dramatically reduced NO-induced apoptosis in chondrocytes, as determined by phase-contrast microscopy, the MTT assay, FACS analysis, and DAPI staining. Treatment with resveratrol inhibited the SNP-induced expression of p53 and p21 and reduced the expression of procaspase-3 in chondrocytes, as detected by western blot analysis. SNP-induced degradation of I-kappa B alpha ($I{\kappa}B-{\alpha}$) was rescued by resveratrol treatment, and the SN50 peptide-mediated inhibition of NF-kappa B (NF-${\kappa}B$) activity potently blocked SNP-induced caspase-3 activation and apoptosis. Our results suggest that resveratrol inhibits NO-induced apoptosis through the NF-${\kappa}B$ pathway in articular chondrocytes.

• Journal of Microbiology and Biotechnology
• /
• v.30 no.4
• /
• pp.490-496
• /
• 2020

Consumption of anti-inflammatory nutraceuticals may help treat or prevent inflammation-related illnesses such as diabetes, cardiovascular disease, and cancer. This study evaluated the effect of Croton hirtus L'Hér extract (CHE) on lipopolysaccharide (LPS)-induced nitric oxide (NO) production and nuclear factor kappa-B (NF-κB) signaling cascades. CHE significantly suppressed LPS-induced NO production and inducible nitric oxide synthase (iNOS) expression in RAW264.7 macrophages, although cyclooxygenase (COX)-2 expression was not affected. CHE also suppressed LPS-induced IκB kinase (IKK), IκB, and p65 phosphorylation in RAW264.7 cells. Western blot and immunofluorescence assays of cytosol and nuclear p65 and the catalytic subunit of NF-κB showed that CHE suppressed LPS-induced p65 translocation from the cytosol to the nucleus. CHE also suppressed LPS-induced Interleukin (IL)-6 and tumor necrosis factor (TNF)-α production in RAW264.7 cells. These results suggest that CHE prevents NO-mediated inflammation by suppressing NF-κB and inflammatory cytokines.

• Journal of Microbiology and Biotechnology
• /
• v.34 no.6
• /
• pp.1340-1347
• /
• 2024

Ehretia asperula is a medicinal plant of the Ehretiaceae family used to treat inflammatory disorders, but the underlying mechanisms are not fully elucidated. The anti-inflammatory potential was determined based on enzyme cyclooxygenase-2 (COX-2) inhibition, which showed that the 95% ethanol extract (95ECH) was most effective with a half-maximal inhibitory concentration (IC₅₀) value of 34.09 ㎍/mL. The effects of 95ECH on phagocytosis, NO production, gene, and protein expression of the cyclooxygenase 2/prostaglandin E2 (COX-2/PGE2) and inducible nitric oxide synthase/ nitric oxide (iNOS/NO) pathways in lipopolysaccharide (LPS)-induced RAW264.7 cells were examined using the neutral red uptake and Griess assays, reverse-transcriptase polymerase chain reactions (RT-PCR), and enzyme-linked immunosorbent assays (ELISA). The results showed that 95ECH suppressed phagocytosis and the NO production in activated macrophage cells (p < 0.01). Conversely, 95ECH regulated the expression levels of mRNAs for cytokines tumor necrosis factor alpha (TNF-α), interleukin-6 (IL-6), and interleukin-1 beta (IL-1β) as well as the corresponding proteins. In addition, PGE2 production was inhibited in a dose-dependent manner by 95ECH, and the expression of iNOS and COX-2 mRNAs was decreased in activated macrophage cells, as expected. Therefore, 95ECH from E. asperula leaves contains potentially valuable compounds for use in inflammation management.

• Food Science and Biotechnology
• /
• v.18 no.4
• /
• pp.923-927
• /
• 2009

This study is to investigate the anti-inflammatory effects of the ethylacetate extract of Rehmannia glutinosa (RGEAE). The anti-inflammatory activities using nitric oxide (NO), cytokine, and chemokine production in lipopolysaccharide (LPS)-induced RAW 264.7 cells were checked. Results indicated that RGEAE suppressed the NO, interleukin-6 (IL-6), and monocyte chemoattractant protein-1 (MCP-1) production in a dose-dependent manner. Inhibition of NO formation was due to a decrease in inducible NOS (iNOS) expression. It was also found that the anti-inflammatory activities of RGEAE resulted from its inhibitory role on the nuclear factor $(NF)-{\kappa}B$ activation and reactive oxygen species (ROS) production. Therefore, it is suggested that RGEAE has potential as a therapeutic material to attenuate the inflammatory disease such as rheumatoid arthritis.

• Journal of the Korean Applied Science and Technology
• /
• v.36 no.1
• /
• pp.13-22
• /
• 2019

The aim of the present investigation was to assess the oxidation inhibition by nitrogen oxide scavenging activity and physiological activities. Bioactive compound of proanthocyanidin $69.000{\pm}2.737mg$ catechin equivalents (CE)/g dry weight. Antioxidant effects (nitric oxide radical scavenging activity, nitrite scavenging activity, ${\beta}$-carotene bleaching assay and lipid peroxidation inhibition activity) of distilled water (DW), 70% ethanol and n-butanol extract of turmeric (Curcuma longa L.). Turmeric extracts yield were DW 17.11%, 70% ethanol 15.26% and n-butanol 4.12%, respectively. Oxidation inhibition activity of the samples exhibited a dose-dependent increase. However, in the current study, none of the samples evaluated showed activity as strong as the BHA and trolox. Total flavonoid content was the highest in the n-butanol extract, followed by 70% ethanol and DW extract. Further, nitrite scavenging activity was the highest for the n-butanol extract. As a result of this experiment, the turmeric can be utilized as a valuable and potential natural oxidation inhibition for the functional food industry.

• Journal of Physiology & Pathology in Korean Medicine
• /
• v.20 no.2
• /
• pp.414-419
• /
• 2006

Prostaglandins biosynthesis and nitric oxide production have been implicated in the process of inflammation and osteoarthritis. And nitric oxide (NO) activated the MMPs responsible for PG degradation in articular chondrocytes. Therefore, we have studied the effects on anti-inflammation and analgesic by ethyl acetate fraction from 70% ethanol extract of Perilla Frutescens (EPF). EPF inhibited LPS plus inflammation-cytokines-induced proteoglycan (PG) degradation, matrix-metalloproteinase (MMP-2,9) expression in rabbit articular chondrocytes. Also, EPF have inhibitory effects on LPS or LPS plus inflammation cytokines-induced nitric oxide (NO) and PGE2 production in mouse macrophage andrabbit articular chondrocytes. These results suggest that EPF decreases PGE2, iNOS, MMPs activity and PG degradation in mouse macrophage and/or rabbit articular chondrocytes. In vivo, EPF was shown to have inhibitory effects on acetic acid-induced pain. The herbal extract with this profile, may have utility in the treatment of osteoarthritis.

• Biomolecules & Therapeutics
• /
• v.10 no.4
• /
• pp.230-235
• /
• 2002

Gold sodium thiomalate (GST, gold compound) is a widely used anti-arthritic, anti-rheumatic and anti-inflammatory drug that is considered a good alternative to sodium salicylate (NaSA) for individuals who cannot tolerate salicylates. Nitric oxide (NO) synthesized by inducible nitric oxide synthase (iNOS) has been implicated as a mediator of inflammation. Recent evidence suggests that anti-inflammatory effect of NaSA lies in the inhibition of iNOS, but nothing has been reported about the direct effect of iNOS expression by GST. The present study was designed to elucidate sequentially the action mechanisms of GST and NaSA on lipopolysaccharide (LPS) plus interferon-gamma (IFN-$\gamma$) induced iNOS expression in RAW 264.7 macrophages. Both GST and NaSA inhibited NO production and iNOS protein expression in a dose dependent manner. GST inhibited iNOS mRNA expression induced by LPS plus IFN-$\gamma$, whereas NaSA did not. These findings suggest that GST may exert anti-arthritic, anti-rheumatic and anti-inflammatory effect by inhibiting iNOS expression induced by LPS plus IFN-$\gamma$ at transcriptional level, whereas NaSA exert its effect by inhibiting iNOS expression at the translational or posttranslational level.

• Molecules and Cells
• /
• v.21 no.3
• /
• pp.337-342
• /
• 2006

Interstitial cells of Cajal (ICCs) are pacemaker cells that activate the periodic spontaneous depolarization (pacemaker potentials) responsible for the production of slow waves in gastrointestinal smooth muscle. The effects of vasoactive intestinal polypeptide (VIP) on the pacemaker potentials in cultured ICCs from murine small intestine were investigated by whole-cell patch-clamp techniques. Addition of VIP (50 nM-$1{\mu}M$) decreased the amplitude of pacemaker potentials and depolarized resting membrane potentials. To examine the type of receptors involved in ICC, we examined the effects of the $VIP_1$ agonist and found that it had no effect on pacemaker potentials. Pretreatment with $VIP_1$ antagonist ($1{\mu}M$) for 10 min also did not block the VIP (50 nM)-induced effects. On the other hand exposure to 1H-(1,2,4)oxadiazolo(4,3-A)quinoxalin-1-one (ODQ, $100{\mu}M$), an inhibitor of guanylate cyclase, prevented VIP inhibition of pacemaker potentials. Similarly KT-5823 ($1{\mu}M$) or RP-8-CPT-cGMPS ($10{\mu}M$), inhibitors of protein kinase G (PKG) blocked the effect of VIP (50 nM) on pacemaker potentials as did N-nitro-L-arginine (L-NA, $100{\mu}M$), a non-selective nitric oxide synthase (NOS) inhibitor. These results imply that the inhibition of pacemaker activity by VIP depends on the NO-cGMP-PKG pathway.