• The Korean Journal of Physiology and Pharmacology
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• v.16 no.3
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• pp.211-217
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• 2012

Recent studies have demonstrated that nitric oxide (NO) activates transient receptor potential vanilloid subtype 1 (TRPV1) via S-nitrosylation of the channel protein. NO also modulates various cellular functions via activation of the soluble guanylyl cyclase (sGC)/protein kinase G (PKG) pathway and the direct modification of proteins. Thus, in the present study, we investigated whether NO could indirectly modulate the activity of TRPV1 via a cGMP/PKG-dependent pathway in cultured rat dorsal root ganglion (DRG) neurons. NO donors, sodium nitroprusside (SNP) and S-nitro-N-acetylpenicillamine (SNAP), decreased capsaicin-evoked currents ($I_{cap}$). NO scavengers, hemoglobin and 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (CPTIO), prevented the inhibitory effect of SNP on $I_{cap}$. Membrane-permeable cGMP analogs, 8-bromoguanosine 3', 5'-cyclic monophosphate (8bromo-cGMP) and 8-(4chlorophenylthio)-guanosine 3',5'-cyclic monophosphate (8-pCPT-cGMP), and the guanylyl cyclase stimulator YC-1 mimicked the effect of SNP on $I_{cap}$. The PKG inhibitor KT5823 prevented the inhibition of $I_{cap}$ by SNP. These results suggest that NO can downregulate the function of TRPV1 through activation of the cGMP/PKG pathway in peripheral sensory neurons.

• Journal of Life Science
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• v.21 no.12
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• pp.1689-1697
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• 2011

In this study, we investigated the anti-inflammation effect of Persicaria thunbergii (P. thunbergii) on RAW 264.7 murine macrophage cells. The anti-inflammatory activity of P. thunbergii was determined by measuring expression of the LPS-induced inflammatory proteins, inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2) and nuclear factor-${\kappa}B$ (NF-${\kappa}B$), and the production of nitric oxide (NO) and prostaglandin $E_2$ ($PGE_2$). Methanol extract of P. thunbergii decreased the expression of iNOS, COX-2 and NF-${\kappa}B$, and increased the expression of HO-1 in LPS-stimulated RAW264.7 cells. Methanol extract was fractioned by n-butanol, hexane and ethyl acetate (EtOAc) and each fraction was tested for inhibitory effects on inflammation. Among the sequential solvent fractions, the EtOAc soluble fraction was investigated by the expression of prostaglandin $E_2$ ($PGE_2$), and showed decreasing form to the dose-dependent manner. EtOAc extract showed the most effective inhibitory activity of the expression of iNOS, COX-2 and NF-${\kappa}B$, and the production of NO. The study showed that P. thunbergii has anti-inflammatory activity through the decrease of NO and inhibition of iNOS, COX-2, $PGE_2$ and NF-${\kappa}B$ expression, and by the increase of HO-1 enzyme. This study needs for more investigation to find out the most effective single compound with anti-inflammatory activity.

• Archives of Pharmacal Research
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• v.21 no.2
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• pp.128-134
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• 1998

Nitric oxide synthase, NOS (EC.1.14.13.39), was purified from bovine pancreas over 5,500-fold with a 7.6% yield using 30% ammonium sulfate precipitation, and $2^1$,$5^1$-ADP-agarose and calmodulin-agarose affinity chromatography. The purified bovine pancreatic NOS (bpNOS) showed a single band on SDS-PAGE corresponding to an apparent molecular mass of 160 kDa, whereas it was 320 kDa on non-denaturating gel-filtration. This indicated a homodimeric nature of the enzyme. The specific activity of the purified bpNOS was 31.67 nmol L-citrulline fored/mtn/mg protein and an apparent $K\textrm{m}$ for L-arginine was 15.72 $\mu\textrm{M}$, The enzyme activity was dependent on $Ca^{2+}$ and calmodulin, and to a lesser extent on NADPH, FAD and FMN. $H_4B$ was not required as a cofactor for the activity. In an inhibition experiment with L-arginine analogues, $N^G$-nitro-L-arginine (NNA) had the most potent inhibitory effect on bpNOS, and $N^{G}$, $N^{G1}$-dimethyl-L-arginine (symmetric; sDMA) did not have any inhibitory effect. Immunohistochemical analysis of the bovine pancreas using brain type NOS antibody (anti-bNOS antibody) revealed that acinar cells showed strong immunoreactivity against the antibody.

• The Journal of Korean Medicine
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• v.30 no.2
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• pp.88-103
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• 2009

Objectives: There is currently increased interest in the identification of natural antioxidant compounds derived from various plants. Peony Root (PR) is used worldwide for the treatment of many types of cardiovascular disease including atherosclerosis and hypertension. It has been used in Korean traditional medicine for the treatment of glycosuria, hypertension and cancer. However, to date, no studies concerning the antioxidant properties of PR have been conducted. Therefore, this study was conducted to evaluate the in vitro scavenging activity, inhibitory effect of LDL oxidation of pro-oxidant reactive species and anti-thrombosis effect in response to treatment with PR using various screening methods including biological and non-biological oxidants. Methods: In this study, the antioxidant activity of extract from PR was studied with in vitro methods by measuring the antioxidant activity by TEAC, measuring the scavenging effects on reactive oxygen species (ROS) [superoxide anion, hydroxyl radical] and on reactive nitrogen species (RNS) [nitric oxide and peroxynitrite] as well as measuring the inhibitory effect on $Cu^{2+}$-induced human LDL oxidation and the inhibitory effect on collagen-induced platelet aggregation. Results: The PR extracts were found to have a potent scavenging activity of oxidative stress [DPPH, superoxide anion, hydroxyl radical, nitric oxide and peroxynitrite, etc.] as well as an inhibitory effect on LDL oxidation and on platelet aggregation. Conclusions: The PR extracts have anti-oxidative and anti-atherosclerotic effects in vitro system, which can be used for developing pharmaceutical drugs against oxidative stress and atherosclerosis.

• Archives of Pharmacal Research
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• v.25 no.2
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• pp.151-153
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• 2002

Three pseudoguaianolide type sesquiterpenes, bigelovin(1), 2,3-dihydroaromaticin (2), and ergolide (3) were isolated as inhibitory constituents against inducible nitric oxide synthase (iNOS) from the flowers of Inula britannica var. chinensis. Bigelovin (1) exhibited a highly potent inhibitory activity on lipopolysaccharide (LPS)-induced iNOS in murine macrophage RAW 264.7 cells with an $IC_{50}$ value of 0.46 mM, which is about 8 times more potent than the known selective inhibitor of iNOS, $L-N^6-(1-iminoethyl)Iysine{\;}(IC_{50}{\;}3.49{\;}{\mu}M)$. 2,3-Dihydroaromaticin (2) and ergolide (3) also exhibited potent inhibitory activities on LPS-induced iNOS with $IC_{50}$ values of 1.05 and $0.69{\;}{\mu}M$, respectively.

• Preventive Nutrition and Food Science
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• v.12 no.4
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• pp.273-278
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• 2007

In this study, we examined the antimutagenicity of red pepper seed and red pepper pericarp ethanol extracts using the standard Ames test in the presence and absence of S9 mix. The extracts showed inhibitory effects on both the TA98 and TA100 Salmenella Typhimurium strains against the mutagenic activity of promutagen 2-aminoanthracene, and were also protective against the directly acting mutagens sodium azide and 2-nitrofluorene. The red pepper seed elicited stronger antimutagenicity than the red pepper pericarp. Both the red pepper seed and red pepper pericarp directly quenched nitric oxide to different degrees and the scavenging activities increased with increasing concentrations. Nitric oxide scavenging activity ranged from $22{\sim}77%$ in the red pepper seed, and from $36{\sim}49%$ in the red pepper pericarp. The TEAC values for red pepper seed extract were $47.89{\pm}1.64mg\;g^{-1}$ in the ABTS radical scavenging assays, while those of red pepper pericarp extract were $94.18{\pm}1.61mg\;g^{-1}$. Therefore, we conclude that red pepper seed and red pepper pericarp have antimutagenic activities as well as antioxidant activity.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.12
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• pp.1685-1690
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• 2009

In this study, we investigated the effect of C. zawadskii extract on nitric oxide (NO) production, prostaglandin E2 (PGE2) production, protein and mRNA expression of inducible nitric oxide synthase (iNOS) in LPS-induced RAW 264.7 macrophage cells. C. zawadskii extract (5~50 μg/mL) significantly inhibited LPS-induced NO production in a concentration-dependent manner ranging from 23.3% to 100%. Consistent with the inhibitory effect on NO production, C. zawadskii extract inhibited the protein expression and mRNA expression of iNOS. Although flower extracts of C. zawadskii was not effective on the expression of PGE2 and COX-2, flower extracts of C. zawadskii, however, showed a strong anti-inflammatory activity through inhibition of NO production and iNOS expression. The present results suggest that C. zawadskii extract has an inhibitory effect on NO production, and thus can be used as an anti-inflammatory agent.

• Biomolecules & Therapeutics
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• v.16 no.3
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• pp.231-236
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• 2008

The current work was designed to assess novel pharmacological activities of 4-hydroxybenzaldehyde (HD), a major phenolic constituent of various natural products of plant origin, such as Gastrodia elata Blume. HD exhibited a significant inhibition in the chick chorioallantoic membrane (CAM) angiogenesis. HD also displayed an inhibitory effect in acetic acid-induced permeability in mice. Anti-nociceptive activity of HD was convinced using the acetic acid-induced writhing test in mice. HD was able to suppress production of nitric oxide (NO) and induction of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) in the lipopolysaccharide (LPS)-activated RAW264.7 macrophages. HD also diminished the reactive oxygen species (ROS) level elevated in the LPS-activated macrophages. In brief, HD exhibits anti-angiogenic, anti-inflammatory and anti-nociceptive activities possibly via down-regulating iNOS and/or COX-2, which may be partly responsible for pharmacological efficacies of various natural products.

• Proceedings of the PSK Conference
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• 2001.10a
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• pp.270.3-271
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• 2001

• Preventive Nutrition and Food Science
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• v.22 no.1
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• pp.50-55
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• 2017

Raphanus sativus L. (RS) is a cruciferous vegetable that is widely consumed in Korea. The anticancer activity of leaves of RS (RSL) extract has been investigated; however, no studies focused on its anti-inflammatory effects. Therefore, the aim of the current study was to evaluate the anti-inflammatory effects of RSL extract. In brief, RSL powder was fractionated into n-hexane, chloroform, ethyl acetate, n-butanol, and water-soluble fractions. Lipopolysaccharide (LPS)-stimulated RAW264.7 cells were treated with each fraction for initial screening. It was found that the chloroform fraction significantly inhibited nitric oxide release in LPS-stimulated RAW264.7 cells with a half maximal inhibitory concentration value of $196{\mu}g/mL$. In addition, the mRNA and protein expression levels of inducible nitric oxide synthase, measured using reverse transcriptase-polymerase chain reaction and western blotting, respectively, were reduced in a concentration-dependent manner. Moreover, the inflammatory cyclooxygenase-2 enzyme expression decreased. Furthermore, the expression of nuclear factor-kappa B ($NF-{\kappa}B$), the key regulator of the transcriptional activation of the inflammatory cytokine genes, was reduced by the RSL chloroform fraction. Therefore, the results of our study suggest that RSL exhibits anti-inflammatory effects in LPS-stimulated macrophages via $NF-{\kappa}B$ inactivation.