• 대한약학회:학술대회논문집
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• 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
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• pp.313.1-313.1
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• 2002

Nitric oxide (NO) production through the inducible nitric-oxide synthase (iNOS) pathway has been implicated in inflammatory diseases and cellular injury. Inhibition of various genes related to inflammation, including iNOS is one of the major roles of well-known anti-inflammatory drugs. In the present study, the effects of ceramide analogs on iNOS expression and NO production were evaluated to investigate how ceramide and its structurally related analogs modulate NO-mecliated cellular signals and inflammation. (omitted)

• Archives of Pharmacal Research
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• 제27권12호
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• pp.1220-1225
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• 2004

The overproduction of nitric oxide (NO) by inducible nitric oxide synthase (iNOS) is known to be responsible for vasodilation and hypotension observed in septic shock and inflammation. Inhibitors of iNOS, thus, may be useful candidates for the treatment of inflammatory diseases accompanied by overproduction of NO. In the course of screening oriental anti-inflammatory herbs for the inhibitory activity of NO synthesis, a crude methanolic extract of Curcuma zedoaria exhibited significant activity. The activity-guided fractionation and repetitive chromatographic procedures with the EtOAc soluble fraction allowed us to isolate three active compounds. They were identified as 1,7-bis (4-hydroxyphenyl)-1,4,6-heptatrien-3-one (1), procurcumenol (2) and epiprocurcumenol (3) by spectral data analyses. Their concentrations for the 50% inhibition of NO production $(IC_{50})$ in lipopolysaccharide (LPS)-activated macrophages were 8, 75, 77 ${\mu}M$, respectively. Compound 1 showed the most potent inhibitory activity for NO production in LPS-activated macrophages, while the epimeric isomers, compound 2 and 3 showed weak and similar potency. Inhibition of NO synthesis by compound 1 was very weak when activated macrophages were treated with 1 after iNOS induction. In the immunoblot analysis, compound 1 suppressed the expression of iNOS in a dose-dependent manner. In summary, 1,7-bis (4-hydroxyphenyl)-1,4,6-heptatrien-3-one from Curcuma zedoaria inhibited NO production in LPS-activated macrophages through suppression of iNOS expression. These results imply that the traditional use of C. zedoaria rhizome as anti-inflammatory drug may be explained at least in part, by inhibition of NO production.

• Archives of Pharmacal Research
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• 제20권5호
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• pp.438-442
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• 1997

Antisense oligonucleotide represents an interesting tool for selective inhibition of gene expression. However, their low efficiency of introduction within intact cells remains to be overcome. Antisense-$TGF{\beta}$ (25 mer) and antisense-$TGF{\beta}$ (18 mer) were used to study the cellular transport and biological function of antisense oligonucleotide in vitro. Since TGF and TNF play on important role in regulating the nitric oxide production from macrophages, the action of the above antisense oligonucleotides was easily monitored by the determination of nitrite. Poly-L-lysine, benzalkonium chloride and tetraphenylphosphonium chloride were used as polycations, which neutralize the negative charge of antisense oligonucleotide. The production of nitric oxide mediated by .gamma.-IFN in mouse peritoneal macrophage was increased by antisense-TGF.betha. in a dose-dependent manner. Antisense-$TGF{\beta}$ reduced the nitric oxide release from activated RAW 264.7 cells. Significant enhancement in the nitric oxide production was investigated by the cotreatment of poly-L-lysine with antisense-$TGF{\beta}$On the meanwhile, inhibition effect of antisense-$TGF{\beta}$ is not changed by the addition of poly-L-lysine. These results demonstrate that control of expression of $TGF{\beta}$ and TNF.alpha. gene is achieved using antisense technology and the cellular uptake of antisense oligonucleotide could be enhanced by ion-pairing.

• 생명과학회지
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• 제21권4호
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• pp.534-541
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• 2011

Retinoic acid (RA)는 Vitamin A의 대사산물로서 토끼 관절 연골세포의 탈분화를 유도하는 물질로 알려져 있다. 그러나 RA가 탈분화를 조절하는 정확한 메커니즘은 잘 알려져 있지 않다. 따라서, Nitric Oxide (NO)가 유도하는 탈분화에 미치는 RA의 분자적 기전에 관한 연구를 수행하였다. 그 결과, RA는 NO가 유도하는 탈분화를 촉진시키는 것을 확인 할 수 있었다. 이와 같은 결과는 Western blot analysis를 통해 연골세포 분화의 표지 단백질인 type II collagen 및 Sox-9의 발현양상을 통해 확인 할 수 있었으며, Alcian blue staining을 통해 연골세포의 기질을 구성하고 있는 단백질인 sulfated proteoglycan의 발현량을 통해서도 확인 할 수 있었다. 또한, RA는 NO 가 유도하는 ERK의 활성을 더욱 증가 시켰다. ERK의 억제자인 PD98059를 사용하여 ERK의 활성을 억제하였을 때 RA가 감소시키는 type II collagen 및 Sox-9의 발현과 sulfated proteoglycan의 생성 양상이 PD98059에 의해 다시 회복되는 것을 확인 할 수 있었다. 이러한 모든 결과를 종합해 볼 때, RA는 NO가 유도하는 탈분화를 ERK 신호전달경로를 통해 조절하는 것을 확인 할 수 있었다.

• The Korean Journal of Physiology and Pharmacology
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• 제13권6호
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• pp.461-467
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• 2009

The auditory cortex (A1) encodes the acquired significance of sound for the perception and interpretation of sound. Nitric oxide (NO) is a gas molecule with free radical properties that functions as a transmitter molecule and can alter neural activity without direct synaptic connections. We used whole-cell recordings under voltage clamp to investigate the effect of NO on spontaneous GABAergic synaptic transmission in mechanically isolated rat auditory cortical neurons preserving functional presynaptic nerve terminals. GABAergic spontaneous inhibitory postsynaptic currents (sIPSCs) in the A1 were completely blocked by bicuculline. The NO donor, S-nitroso-N-acetylpenicillamine (SNAP), reduced the GABAergic sIPSC frequency without affecting the mean current amplitude. The SNAP-induced inhibition of sIPSC frequency was mimicked by 8-bromoguanosine cyclic 3',5'-monophosphate, a membrane permeable cyclic-GMP analogue, and blocked by 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide, a specific NO scavenger. Blockade of presynaptic $K^+$ channels by 4-aminopyridine, a $K^+$ channel blocker, increased the frequencies of GABAergic sIPSCs, but did not affect the inhibitory effects of SNAP. However, blocking of presynaptic $Ca^{2+}$ channels by $Cd^{2+}$, a general voltage-dependent $Ca^{2+}$ channel blocker, decreased the frequencies of GABAergic sIPSCs, and blocked SNAP-induced reduction of sIPSC frequency. These findings suggest that NO inhibits spontaneous GABA release by activation of cGMP-dependent signaling and inhibition of presynaptic $Ca^{2+}$ channels in the presynaptic nerve terminals of A1 neurons.

• Biomolecules & Therapeutics
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• 제19권4호
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• pp.419-424
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• 2011

Galla Rhois and its components are known to possess anti-infl ammatory properties. In the present study, we prepared equilibrium mixture of ethyl m-digallate and ethyl p-digallate isomers (EDG) from Galla Rhois and examined its effect on nitric oxide (NO) production in murine macrophage cell line. Treatment of RAW264.7 macrophages with EDG signifi cantly inhibited NO production and inducible nitric oxide synthase (iNOS) expression stimulated by LPS, as assessed by Western blot and quantitative RT-PCR analyses. We also demonstrated that EDG treatment led to an increase in heme oxygenase-1 (HO-1) mRNA and protein expression. EDG treatment also enhanced expression level of nuclear factor-erythroid 2-related factor 2 (Nrf2) in nucleus, which is critical for transcriptional induction of HO-1. Treatment with SnPP (tin protoporphyrin IX), a selective HO-1 inhibitor, reversed EDG-mediated inhibition of nitrite production, suggesting that HO-1 plays an important role in the suppression of NO production by EDG. Taken together, these results indicate that EDG isolated from Galla Rhois suppresses LPS-stimulated NO production in RAW 264.7 macrophages via HO-1 induction.

• Archives of Pharmacal Research
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• 제27권1호
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• pp.94-98
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• 2004

Effects of dopaminergic drugs on the degranulation of mast cells (RBL-2H3 cells) and the nitric oxide production from macrophage cells (RAW 264.7) were studied. Among the dopaminergic agonists and antagonists tested, bromocriptine, 7-OH-DPAT, haloperidol, and clozapine showed potent inhibitions of mast cell degranualtion ($IC_{50} value, 5 \mu$ M). However, these dopaminergic agents did not affect the tyrosine phosphorylations of the signaling components of the high affinity IgE receptor ($Fc\varepsilonRI$), such as Syk, $PLC\gamma1$, and $PLC\gamma2$.; This suggested that these signaling components were not involved in the inhibition of the mast cell degranulation by these compounds. On the other hand, dopamine, bromocriptine, 7-OH-DAPT, and haloperidol markedly inhibited the nitric oxide production from RAW 264.7 cells ($IC_{50}$ values, 10-20$\mu$M). Bromocriptine, a dopamine agonist that is routinely used for the treatment of Parkinsons disease, inhibited the expression of the inducible nitric oxide synthase at an early stage of the LPS-induced protein expression in a dose-dependent manner. The results suggested that these dopaminergic agents, when used for the treatment of dopamine receptors-related diseases, such as Schizophrenia or Parkinsons disease, might have additional beneficial effects.

• 대한본초학회지
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• 제21권2호
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• pp.165-173
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• 2006

Objectives : Coptidis Rhizoma has been known traditional medicine with antimicrobial activities. We investigated inhibitory effects of Coptidis Rhizoma extract on lipopolysaccharide(LPS)-induced nitric oxide production from mouse macrophages. Methods : After Coptidis Rhizoma extract was pretreated in BV2, mouse brain macrophages and RAW264.7 mouse macrophages, cells were activated with LPS. To investigate cytotoxicity Coptidis Rhizoma extract, cell viability was measured by MTT assay. The production of nitric oxide(NO) and inducible nitric oxide synthase(iNOS) was determined in each culture supernatant and mRNA by Griess reaction and RT-PCR. The production of $TNF-{\alpha}$ from cells was measured by ELISA. Results : Coptidis Rhizoma extract significantly inhibited LPS-induced NO production in BV2 and RAW264.7 cells. Coptidis Rhizoma extract also greatly suppressed mRNA expression of iNOS in BV2 and RAW264.7 cells activated by LPS. Conclusion : These data suggests that Coptidis Rhizoma extract may have an anti-inflammatory effect through the inhibition of NO production.

• 약학회지
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• 제45권1호
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• pp.85-92
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• 2001

Nitric oxide is a tonically produced vasodilator that maintains blood pressure in the normal animal. The chronic inhibition of nitric oxide synthase (NOS) elicits the hypertension in rats. However, the mechanism of hypertension induced by chronic inhibition of NOS is not clear. Thus, to clarify the mechanism of the occurance of hypertension, the changes in $\alpha$-adrenergic systems in rats treated with NOS inhibitors for 21 days were examined. Chronic administration of L-NAME significantly increased in the basal blood pressure, but chronic administration of 7-nitroindazole did not. Phenylephrine and G-protein stimulator elicited the more potent contraction in the aorta of the L-NAME-induced hypertensive rats. However when the contractile responses by phenylephrine and G-protein stimulator were calculated the proportion to the contraction by 25 mM KCL, there was no difference between the vehicle-treated rats and the L-NAME-treated rats. The density of $\alpha$-adrenergic receptors in aortic tissue was not changed by the chronic inhibition of NOS. These results suggest that hypertension induced by chronic inhibition of NOS is due to the inhibition of eNOS and the increased responses to the adrenergic drugs are due to the changes of the intracellular contactile mechanism of aortic tissue rather than the changes of receptor density.

• Preventive Nutrition and Food Science
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• 제13권4호
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• pp.362-365
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• 2008

Agaricus bisporus, also known as white button mushroom, is one of the most popular mushrooms consumed in Korea. This mushroom contains high concentrations of flavanoids and exhibits antioxidant activity. In this study, we examined the effects of Agaricus bisporus ethanol extract (ABE) on lipopolysaccharide (LPS)-induced inflammation in RAW 264.7 cells. Nitric oxide (NO) production and inducible nitric oxide synthase (iNOS) protein levels were assessed in cells treated with $100\;{\mu}M$ LPS in the presence or absence of ABE. 0.5 mg/mL of ABE suppressed NO production significantly. Moreover, ABE inhibited levels of iNOS protein. Taken together, these results suggest that ABE exerts anti-inflammatory activity in LPS-induced inflammation in RAW 264.7 cells.