• Biomolecules & Therapeutics
• /
• 제12권4호
• /
• pp.209-214
• /
• 2004

Lead has long been considered as a toxic environmental pollutant that severely damages the central nervous system. In various neurogenerative diseases, actrocytes become activated by proinflammatory cytokines. In the present study, we investigated whether lead (Pb$^{2+}$) affects inducible nitric oxide synthase (iNOS) expression in activated glial cells. Rat primary glial cells were stimulated with lipopolysaccharide (LPS, 1 ${\mu}$g/ml) plus IFN$_{\gamma}$(100 U/ml). Pre-treatment of Pb$^{2+}$ increased nitric oxide (NO) production in LPS/IFN$_{\gamma}$-stimulated glial cells. Lead itself, however, suppressed the basal production of NO in control glial cells. Addition of the iNOS inhibitors L-NAME (1 mM) and L-NNA (800 ${\mu}$M) prevented the Pb$^{2+}$-induced increase in NO production. Western blot analysis showed that pre-treatment of Pb$^{2+}$ augmented LPS/IFN$_{\gamma}$-induced increase in iNOS immunoreactivity, which was well correlated with the increased NO production. In addition, pre-treatment of Pb$^{2+}$ synergistically increased the iNOS mRNA expression induced by LPS and IFN${\gamma}$. The present results indicate that lead intoxication adversely affect brain function by potentiating iNOS expression and NO production in activated glial cells observed in various neurodegenerative diseases.

• Korean Journal of Acupuncture
• /
• 제34권1호
• /
• pp.37-46
• /
• 2017

Objectives : The acupuncture about acupoint affects the production of NO, NOS, and NE.Local action of acupuncture is important for acupuncture treatment. To prove this, the revelation degree of NO, NOS, and NE was observed by stimulating the acupuncture at the connecting point of SP4, KI4, and LR5 in the depths of Superficial layer, Middle layer and Deep layer. Methods : Needles were inserted into rats, on each right and left sides of the connecting point, SP4, KI4 and LR5 acupoints which are the stream points of the foot meridian. After insertion, needles were retained for three minutes. After the retention, rat was sacrificed via cardiac puncture, and tissues of each SP4, KI4 and LR5 point near meridian vessel was extracted to examine the changes in the expression of NO, NOS and NE. Results : In terms of the effect in NO production, there was significant increase in the Superficial layer, Middle layer and Deep layer at KI4. In terms of the effect in NE production, there was significant decrease in the Superficial layer at SP4 and increase in the Superficial layer, Middle layer and Deep layer at LR5. In terms of the effect in nNOS production, there was significant increase in the Superficial layer, Middle layer and Deep layer at SP4 also in the Superficial layer at KI4. In terms of the effect in eNOS production, there was a significant increase in the Superficial layer, Middle layer and Deep layer at SP4, KI4 and LR5. In terms of the effect in iNOS production, there was significant increase in the Superficial layer, Middle layer and Deep layer at SP4, KI4 and LR5. Conclusions : The effect of acupuncture applied at the connecting point of six meridians of the foot on the activities of NO, NOS and NE could be observed, and it can be induced from the effect of needle stimulation on disrupted local and systemic nervous responses.

• 생약학회지
• /
• 제42권4호
• /
• pp.348-353
• /
• 2011

The aim of the present study is to investigate the cytokine production inhibitory effect of a Dictamni Radicis Cortex (DRC). DRC has been commonly used as important medicinal herb in China and it used to control eczema, atopic dermatitis, fever and inflammatory diseases. Inflammation, such as a bacterial infection in vivo metabolites, such as external stimuli or internal stimuli to the defense mechanisms of the biological tissue a variety of intracellular regulatory factors deulin inflammatory TNF-${\alpha}$, IL-$1{\beta}$, IL-6, IL-8, such as proinflammatory cytokines, prostagrandin, lysosomal enzyme, free radicals are involved in a variety of mediators. The present study was designed to determine the effect of the DRC on proinflammatory factors such as NO, iNOS expression and TNF-${\alpha}$, IL-$1{\beta}$, IL-6 in lipopolysaccharide (LPS) - stimulated RAW264.7 cells. The cell toxicity was determined by MTS assay. To evaluate of anti-inflammatory effect of DRC, amount of NO was measured using the NO detection kit and the iNOS expression was measured by reverse transcriptase polymerase chain reaction (RT-PCR). And proinflammatory cytokines were measured by ELISA kit. As a result, the DRC reduced NO, iNOS expression and TNF-${\alpha}$, IL-$1{\beta}$, IL-6 production without cytotoxicity. Our results suggest that the DRC may have an anti-inflammatory property through suppressing inflammatory mediator productions.

• 한국응용약물학회:학술대회논문집
• /
• 한국응용약물학회 2003년도 Annual Meeting of KSAP : International Symposium on Pharmaceutical and Biomedical Sciences on Obesity
• /
• pp.101-101
• /
• 2003

Prostaglandins (PGs) and nitric oxide (NO) produced by inducible cyclooygenase (COX-2) and nitric oxide synthase (iNOS), respectively, have been implicated as important mediators in the process of inflammation and carcinogenesis. On this line, the potential COX-2 or iNOS inhibitors have been considered as anti-inflammatory and cancer chemopreventive agents. In our continuing efforts of searching for novel cancer chemopreventive agents from natural products, we isolated natural sesquiterpenoids as potential COX-2 and iNOS inhibitors in cultured lipopolysaccharide (LPS)-activated mouse macrophage RAW 264.7 cells. Alantolactone, a natural eudesmane-type sesquiterpenoid, exhibited a potent inhibition of COX-2 (IC50 = 0.4 $\mu\textrm{g}$/$m\ell$) and iNOS activity (IC50 = 0.08 $\mu\textrm{g}$/$m\ell$) in the assay system determined by PGE2 and NO accumulation, respectively. The inhibitory potential of alantolactone on the PGE2 and NO production was well coincided with the suppression of COX-2 and iNOS protein and mRNA expression in LPS-induced macrophages. Furthermore, alantolactone inhibited NF-kB but not AP-l binding activity on nuclear extracts evoked by LPS-stimulated macrophage cells, suggesting the possible involvement of NF-kB in the regulation of COX-2 and iNOS expression. In further study with COX-2-expressing human colon HT-29 cells, alantolactone inhibited the cell proliferation, down-regulated COX-2, and inhibited the ERK phosphorylation in the early time. These results suggest that a natural sesquiterpenoid alantolactone might be a potential lead candidate for further developing COX-2 or iNOS inhibitor possessing cancer chemopreventive or anti-inflammatory activity

• Natural Product Sciences
• /
• 제20권4호
• /
• pp.227-231
• /
• 2014

Cimicifuga heracleifolia extract (CHE) was investigated for its effects on the release of nitric oxide (NO) and at the level of inducible nitric oxide synthase (iNOS) gene expression in mouse macrophages. We found that C. heracleifolia elicited a dose-dependent increase in NO production and the level of iNOS mRNA. Since, iNOS transcription has been shown to be under the control of the transcription factor $NF-{\kappa}B$, the effects of CHE on $NF-{\kappa}B$ activation were examined. Transient expression assays with $NF-{\kappa}B$ binding sites linked to the luciferase gene revealed that the increased level of iNOS mRNA, induced by CHE, was mediated by the $NF-{\kappa}B$ transcription factor complex. By using DNA fragments containing the $NF-{\kappa}B$ binding sequence, CHE was shown to activate the protein/DNA binding of $NF-{\kappa}B$ to its cognate site, as measured by electrophoretic mobility shift assay. These results demonstrate that C. heracleifolia stimulates NO production and is able to up-regulate iNOS expression through $NF-{\kappa}B$ transactivation.

• Natural Product Sciences
• /
• 제11권1호
• /
• pp.16-21
• /
• 2005

Nitric Oxide (NO), derived from L-arginine, is produced by two types (constitutive and inducible) of nitric oxide synthase (NOS: cNOS and iNOS). The NO produced in large amounts by the iNOS is known to be responsible for the vasodilation and hypotension observed in septic shock, cancer metastasis and inflammation. The inhibitors of iNOS, thus, may be useful candidates for the treatment of inflammatory diseases accompanied by the overproduction of NO. We prepared alcoholic extracts of herbal drugs which have been used for the treatment of inflammation in oriental medicine. We have screened the inhibitory activity of NO production in lipopolysaccharide (LPS)-activated macrophages after the treatment of these extracts. Among 82 kinds of extracts of herbal drugs, 35 extracts showed the potent inhibitory activity of NO production above 50% at the concentration of $50\;{\mu}g/mL$. The inhibitory activities of NO production were also evaluated for several solvent fractions at two different concentrations. Especially, hexane and EtOAc fractions of Alpinia officinarum, Angelica gigas, Ostericum koreanum, Saussurea lappa, Torilis japonica, and hexane fractions of Agrimonia pilosa, Machilus thunbergii, Hydrangea serrata, Magnolia obovata, Prunella vulgaris, Tussilago farfara, and EtOAC fractions of Perilla frutescence showed a significant activity at 10 and/or $25\;{\mu}g/mL$. In Western blot analysis, the hexane fractions ($5\;{\mu}g/mL$) of Magnolia obovata and Saussurea lappa, and EtOAc fractions ($20\;{\mu}g/mL$) of Hydrangea Serrata, Perilla frutescence and Torilis japonica inhibited the expression of iNOS protein in LPS-activated macrophages. These plants may be promising candidates for the study of the activity-guided purification of active compounds and might be useful for the treatment of inflammatory diseases and endotoxemia accompanying overproduction of NO.

• 대한의생명과학회지
• /
• 제25권2호
• /
• pp.196-200
• /
• 2019

Effect of retinoids, i.e., all-trans retinoic acid and 13-cis retinoic acid, on the activity of nitric oxide synthase (NOS) was evaluated in human malignant keratinocytes to examine the possible correlation of retinoids with NOS activities. All-trans retinoic acid and 13-cis retinoic acid did not alter the nitric oxide (NO) production. However, in the presence of lipopolysaccharide (LPS, $1{\mu}g/mL$), they significantly increased NO release in a dose-dependent manner until 48 h at concentrations of $50{\sim}100{\mu}M$. The degree of upregulation of NO by all-trans retinoic acid and 13-cis retinoic acid increased up to 35% and 37%, respectively, compared to that by the control, which demonstrated the upregulation of LPS-inducible nitric oxide synthase (iNOS)-dependent generation of NO as well as showing a crucial link between retinoids-induced activity and NOS. Findings of this study now suggest that the upregulation of LPS-iNOS activity may be associated with modulation of retinoids-induced control of cellular developmental processes, which may produce new therapeutics of retinoids in the complexity of how NO affects human keratinocytes.

• 한국독성학회:학술대회논문집
• /
• 한국독성학회 2002년도 Current Trends in Toxicological Sciences
• /
• pp.100-100
• /
• 2002

2-amino-3-methylimidazo[4,5-f]quinoline (IQ), a heterocyclic amine, significantly inhibits nitric oxide (NO) production in lipopolysaccharide (LPS)-stimulated macrophages. The decrease in NO production was found to correlate well with a decrease in iNOS mRNA expression as demonstrated by Northern blot analysis.(omitted)

• Environmental Analysis Health and Toxicology
• /
• 제15권3호
• /
• pp.69-80
• /
• 2000

ADP-rubosylation may be involved in the process of macrophage activation. Nitric oxide (NO) has emerged as an important intracellular and interacellular regulatory molecule with function as diverse as vasodilation, neural communication or host defense. NO is derived from the oxidation of the terminal guanidino nitrogen atom of L-arginine by the NADPH -dependent enzyme, nitric oxide synthase (NOS) which is one of the three different isomers in mammalian tissues. Since NO can exert protective or regulatory functions in the cell at a low concentration while toxic effects at higher concentrations, its role may be tightly regulated in the cell. Therefore, this paper was focused on signal transduction pathway of NO synthesis, role of endogenous TGF-$\beta$ in NO production. effect of NO on superoxide formation. Costimulation of murine peritoneal macrophages with interferon-gamma (IFN-γ) and phorbol 12-myristate 13-acetate (PMA) increased both NO secretion and mRNA expression of inducible nitric oxide synthase (iNOS) when PMA abolished costimulation. Pretreatmnet of the cells with PMA abolished costimuation effects due to the depletion of protein kinase C (PKC) activities . The involvement of PKC in NO secretion could be further confirmed by PKC inhibitor, stauroprine, and phorbol ester derivative, phorbol 12,13-didecanoate. Addition of actinomycine D in IFN-γ plus PMA stimulated cells inhibited both NO secretion and mRNA expression of iNOS indication that PMA stabilizes mRNA of iNOS . Exogenous TGF-$\beta$ reduced NO secretion in IFN -γ stimulated murine macrophages. However addition of antisense oligodeoxynucleotide (ODN) to TGF-$\beta$ to this system recovered the ability of NO production and inhibited mRNA expression of TGF-$\beta$. ACAS interactive laser cytometry analysis showed that transportation of FITC -labeled antisense ODN complementary to TGF-$\beta$ mRNA could be observed within 5 min and reached maximal intensity in 30 min in the murine macrophage cells. NO released by activated macrophages inhibits superoxide formation in the same cells . This inhibition nay be related on NO-induced auto -adenosine diphosphate (ADP) -ribosylation . In addition, ADP-ribosylation may be involved in the process of macrophage activation .

• The Korean Journal of Physiology and Pharmacology
• /
• 제17권4호
• /
• pp.315-320
• /
• 2013

Here, we show that radicicol, a fungal antibiotic, resulted in marked inhibition of inducible nitric oxide synthase (iNOS) transcription by the pancreatic beta cell line MIN6N8a in response to cytokine mixture (CM: TNF-${\alpha}$, IFN-${\gamma}$, and IL-$1{\beta}$). Treatment of MIN6N8a cells with radicicol inhibited CM-stimulated activation of NF-${\kappa}B$/Rel, which plays a critical role in iNOS transcription, in a dose-related manner. Nitrite production in the presence of PD98059, a specific inhibitor of the extracellular signal-regulated protein kinase-1 and 2 (ERK1/2) pathway, was dramatically diminished, suggesting that the ERK1/2 pathway is involved in CM-induced iNOS expression. In contrast, SB203580, a specific inhibitor of p38, had no effect on nitrite generation. Collectively, this series of experiments indicates that radicicol inhibits iNOS gene expression by blocking ERK1/2 signaling. Due to the critical role that NO release plays in mediating destruction of pancreatic beta cells, the inhibitory effects of radicicol on iNOS expression suggest that radicicol may represent a useful anti-diabetic activity.