• Natural Product Sciences
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• v.19 no.1
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• pp.8-14
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• 2013

The inhibitory effect and the structure-activity relationships of luteolin and its related derivatives isolated from Taraxacum mongolicum against MAO activities were investigated. The activity-guided isolation of extract from Taraxacum mongolicum led to the isolation of three flavonoids, luteolin, diosmetin, and luteolin-7-glucoside, a polyphenol, chlorogenic acid, a tyrosine and a uridine. The inhibitory activities of luteolin and its related derivatives against MAOs activities are dependent on their molecular structures. The presence of the phenolic hydroxy group at para-position is the active site for MAO-A inhibition as well as of MAO-B. The methoxy group has no potential on MAO-A inhibition. An additional phenolic hydroxy group at the ortho-position alleviates about 4-fold MAO-A inhibitory activity of phenolic hydroxy group at para-position. A carboxylic group seems to be critical for DBH inhibition and has no effects on MAO.

• Natural Product Sciences
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• v.25 no.1
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• pp.34-37
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• 2019

Phytochemical studies were performed to identify the active principles of Phryma leptostachya var. asiatica (Phyrymaceae) for anti-inflammation. The anti-inflammatory activity was assessed by measuring the inhibition rate on nitric oxide (NO) formation in lipopolysaccharide (LPS)-activated macrophage 264.7 cells. Of the five compounds including ursolic acid, phrymarolin I, harpagide, haedoxancoside A, and acteoside isolated from this plant, ursolic acid showed the most prominent inhibition of NO formation. Therefore, ursolic acid may be the anti-inflammatory principle of Phryma leptostachya var. asiatica.

• Archives of Pharmacal Research
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• v.27 no.12
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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.

• Journal of Digital Convergence
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• v.12 no.3
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• pp.359-366
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• 2014

This study investigated the impact on S. mutans와 C. albicans in order to reveal the antimicrobial activity of Platycodon grandiflorum extracts. In addition, it examined NO generation inhibition rate in accordance with the extract concentration from Raw 264.7 cell in order to find out anti-inflammatory activation. As for the study materials, domestically made 100% Platycodon grandiflorum powder was utilized. As for the experimental strain, S. mutans KCTC 3065 and C. albicalns KCTC 7965 were utilized. Consequently, this study obtained the following results. Growth inhibition rate of S. mutans became significantly higher with higher concentration of Platycodon grandiflorum extracts. Growth inhibition rate of C. albicans became significantly higher with higher concentration of Platycodon grandiflorum extracts. NO generation inhibition rate was found to be 29.2% and 26.1% respectively when adding Platycodon grandiflorum extract with the concentration of 10 and $20{\mu}g/ml$ in Raw 264.7 cells. These results mean that Platycodon grandiflorum could be leveraged as antimicrobial and anti-inflammatory substance.

• The Korean Journal of Pharmacology
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• v.27 no.2
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• pp.145-153
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• 1991

Human neutrophil cathepsin-G, which has been known as one of the active enzymes causing inflammatory diseases, was purified by two steps procedure involving one size exclusion (Ultorogel AcA54) and one ion exchange (CM-Sephadex) chromatography. Purified HNCGs were cross-reacted with Anti-HNCathepsin-G antibodies which were radised in rabbits and purified by cathepsin-G labeled Sepharose 4B affinity chromatography. HNCGs were effectively inhibited by NSAIDs including phenylbutazone, sulindac, oxyphenbutazone, salicylic acid and salicyluric acid. $IC_{50}_s$ of these drugs for inhibition of Cathepsin G were 0.3-0.8 mM. Other NSAIDs including aspirin showed little or no inhibition effect on the activity of Cathepsin G. These results strongly indicated that NSAIDs which showed inhibition effect on the activity of HNCGs possibly be at least a part of mechanism of action which might be related to direct inhibition of cathepsin G at the tissue destruction sites beside of their known mechanism of action as an anticyclo-oxygenase in treatment of inflammatory diseases. Lipid soluble component of Korean Red Ginseng which was known as an anti-inflammatory agent inhibited HNCGs strongly, but no other fractions did inhibited HNCGs. Antibiotics including novobiosin and rifamycin showed some inhibition effect on HNCGs, i. e.., $IC_{50}$ of these drugs were 2.6 mM and 1.5 mM respectively, and other antibiotics including penicillin G showed no or negligible inhibition effect on the activity of HNCGs. However. tetracyclines inhibited HNCGs very effectively at the concentration of therapeutic range. The inhibition effect of the activity of HNCGs by tetracycline are not related to the N-dimethyl radical on the 4 position of the tetracycline molecule. Furthermore, N-dedimethylated tetracyclines may have beneficial effect for long term treatment of chronic inflammatory diseases without developing any drug resistance to microorganisms.

• Journal of Environmental Science International
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• v.26 no.11
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• pp.1285-1295
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• 2017

Chrysanthemum boreale Makino is widely distributed in Korea, China, Japan and Southeast Asian countries. C. boreale is one of the herbs used for treating various inflammatory diseases in oriental medicine. The present study was conducted to identify biologically active compounds from the leaves and stems of C. boreale. We isolated two sesquiterpene sactones from the leaves and stems of C. boreale using silica gel column chromatography and recyclic high perfomance liquid chromatography. The lactones were characterized by their spectroscopic data (NMR, IR, MASS). These compounds were subjected to Farnesyl Protein Transferase (FPTase) inhibition, Nitric Oxide (NO) release inhibition and apoptosis inhibition. The structur of the following isolated compound were elucidated 8,10-${\small{O}$-Acetyl-2-methoxy-10-hydroxy-3,11(13)-guaiadiene-12,6-olide and 4,10-dihydroxy-8-${\small{O}$-Acetyl-2,11(13)-guaiadiene-12,6-olide. In the NO release inhibition assay, compound 2 showed strong activities, with an $IC_{50}$ value of $7{\mu}g/mL$, whereas compound 1 did not exhibit significant activity with an $IC_{50}$ value of over $14{\mu}g/mL$ against murine macrophage.

• The Korean Journal of Physiology and Pharmacology
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• v.15 no.3
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• pp.123-128
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• 2011

Caesalpinia sappan (C. sappan) is a medicinal plant used for promoting blood circulation and removing stasis. During a screening procedure on medicinal plants, the ethylacetate extract of the lignum of C. sappan (CLE) showed inhibitory activity on arginase which has recently been reported as a novel therapeutic target for the treatment of cardiovascular diseases such as atherosclerosis. CLE inhibited arginase II activity prepared from kidney lysate in a dose-dependent manner. In HUVECs, inhibition of arginase activity by CLE reciprocally increased NOx production through enhancement of eNOS dimer stability without any significant changes in the protein levels of eNOS and arginase II expression. Furthermore, CLE-dependent arginase inhibition resulted in increase of NO generation and decrease of superoxide production on endothelium of isolated mice aorta. These results indicate that CLE augments NO production on endothelium through inhibition of arginase activity, and may imply their usefulness for the treatment of cardiovascular diseases associated with endothelial dysfunction.

• Natural Product Sciences
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• v.27 no.1
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• pp.28-35
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• 2021

The aim of this study was to anatomize the therapeutic potential of alaternin (=7-hydroxyemodin) against inflammation, advanced glycation end products (AGEs) formation, tyrosinase, and two cyclin-dependent kinases (CDKs), CDK2 and CDK4, and compare its potency with emodin. Alaternin showed lower cytotoxicity and higher dose-dependent inhibition against lipopolysaccharide (LPS) induced nitric oxide (NO) production with half maximal inhibitory concentration (IC50) of 18.68 µM. Similarly, alaternin efficaciously inhibited biotransformation of fluorescent AGEs and amyloid cross-β structure on the bovine serum albumin (BSA)-glucose-fructose system, five times more than emodin. Interestingly, alaternin also showed selective activity against CDK4 at 170 µM, whereas emodin inhibited both CDK2 and CDK4 at a concentration of 17 and 380 µM respectively. In addition, alaternin showed dose-dependent inhibitory activity against mushroom tyrosinase with inhibition percentage of 35.84 % at 400 µM. Altogether, alaternin with pronounced inhibition against inflammatory mediator (NO), glycated products formation, and targeted inhibition towards CDK4 receptor can be taken as an important candidate to target multiple diseases.

• YAKHAK HOEJI
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• v.45 no.1
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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.

• Journal of Microbiology
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• v.35 no.2
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• pp.152-157
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• 1997

Infection of human fibroblast (HF) cells with human cytomegalovirus (HCMV) result in changes in the intracellular level of second messengers. Since nitric oxide (NO) production has been known to be related with other second messengers, it is probable that HCMV infection of HF cells may involve NO. To test this possibility, the amount of NO was measured following ogenous addition of NO generators such as sodium nitroprusside (SNP) or S-nitroso-N-a-cetylpenicillamine (SNAP) immediately after HCMV infection, however, inhibited virus multiplication. Furthermore, immunoblot experiment using monoclonal antibody to HCMV major immediate early (MIE) proteins or CAT assay using pCMVIE/CAT (plasmid containing CAT gene driven by HCMV MIE promoter) revealed that SNP or SNAP blocked the MIE gene expression. SNP was more effective than SNAP in hibiting HCMV multiplication or MIE gene expression. SNP produced more NO than SNAP in inhibiting HCMV multiplication or MIE gene expression. SNP produced more NO than SNAP. Although the mechanism for the inhibition of HCMV multiplication and MIE gene expression by NO is still elusive some correlation with NO-mediated inhibition of HCMV-induced increase in cytosolic free Ca$\^$2+/ concentration ([Ca$\^$2+/]) was observed. The increase of [Ca$\^$2+/] following HCMV infection was inhibited by SNP, and less effectively by SNAP. Raising [Ca$\^$2+/ with bromo-A23187 partially reversed the SNP block of MIE gene expression. Thus, there appear to e some relationships among NO. [Ca$\^$2+/], and HCMV MIE gene expression.