• Biomolecules & Therapeutics
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• 제14권1호
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• pp.11-18
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• 2006

Certain flavonoids possess anti-inflammatory activity. Besides their antioxidative property, the cellular action mechanisms of flavonoids include an inhibition of arachidonate metabolizing enzymes such as cyclooxygenases and lipoxygenases, and a down-regulation of proinflammatory gene expression such as cyclooxygenase-2, inducible nitric oxide synthase and tumor necrosis factor-$\alpha$. In this review, the recent findings of anti-inflammatory flavonoid research since 2004 were summarized. And the cellular mechanisms on signal transduction pathways were also discussed.

• Natural Product Sciences
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• 제19권2호
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• pp.186-191
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• 2013

Screenings of potential antioxidant activities of Crataegus pinnatifida BUNGE Major. fruits extracted 80% methanol were performed using four antioxidant assays. Significant differences were observed both in total phenolic contents (TPC) and total flavonoid contents (TFC), DPPH radical scavenging activity, nitric oxide scavenging activity, ABTS radical scavenging assay, and reducing power assay. The total polyphenol content and total flavonoid content in the extract were measured to be $224.4{\pm}0.52$ mg GAE/100 g and $12{\pm}0.25$ mg QE/100 g, respectively. When the tested concentration was $500{\mu}g/mL$, DPPH and ABTS radical-scavenging activities of methanolic extracts were 84.15% and 88.8%, respectively. The reducing power and nitric oxide scavenging activity were increased at the manner of dose-dependently. These results suggest that methanolic extracts of Crataegus pinnatifida Bge. fruits possess excellent radical scavenging activities and may serve as a potential source of natural antioxidant.

• 한국약용작물학회지
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• 제21권3호
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• pp.191-196
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• 2013

The effect on the antioxidant activity and Nitric Oxide activity production inhibitory activity of Taraxacum has not been known. Therefore, phenolics and flavonoid contents were investigated from the ethanol extracts of five different Taraxacum species. The results showed that, among the five Taraxacum, T. hallaisanensis contains the highest total phenolic and flavonoid contents. When the antioxidant activity was measured by DPPH, $ABTS^+$ and reducing power activity, the free radical scavenging activity of T. hallaisanensis was also the highest among five Taraxacum species. However, measurement by CCK-8 assay in Raw264.7 cells indicated that the extracts of Taraxacum species have no effect on cell viability. Moreover, we also investigated the effect of Taraxacum species on NO scavenging activity in lipopolysaccharide (LPS)-stimulated Raw264.7 cells. The results clearly showed that Taraxacum species inhibited NO production, and the inhibitory effect of T. hallaisanensis was the strongest. The above results suggested that Taraxacum species affected the antioxidant and NO scavenging activity, and among the five species, antioxidant and NO scavenging activity assay of T. hallaisanensis was significantly higher than those of other four Taraxacum species. Therefore, T. hallaisanensis could be used as a potential drug with anti-oxidant and anti-inflammatory effect.

• Natural Product Sciences
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• 제6권4호
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• pp.170-178
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• 2000

Flavonoids are natural polyphenolic compounds widely distributed in plant kingdom. Although many flavonoids were found to show anti-inflammatory activity in vitro and in vivo, the potency of anti-inflammatory activity was not enough for a clinical trial. Thus, a search for finding potential flavonoid molecules is continuing. In this review, in vivo anti-inflammatory activity of various flavonoid derivatives is summarized mainly based on the results obtained in authors' laboratories. Among them, several biflavonoids such as amentoflavone and ginkgetin were found to possess anti-inflammatory activity on animal models of acute/chronic inflammation comparable to nonsteroidal and steroidal anti-inflammatory drugs currently used. In respect of their action mechanisms, the effects on arachidonic acid metabolism and nitric oxide production were described. Some flavonoids directly inhibit cyclooxygenase and/or lipoxygenase. Biflavones such as ochnaflavone and ginkgetin are inhibitors of phospholipase $A_2$. In recent studies, certain flavonoids were also found to suppress cyclooxygenase-2 and inducible nitric oxide synthase expression induced by inflammatory stimuli. Therefore, it is suggested that anti-inflammatory activity of the certain flavonoids (mainly flavones, flavonols and biflavonoids) may be mediated by direct inhibition of arachidonic acid metabolizing enzymes as well as suppression of the enzyme expression involved in inflammatory responses.

• 한국식품과학회지
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• 제51권2호
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• pp.133-140
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• 2019

Antioxidant activities of Ulmus davidiana root and bark extracts were evaluated by various antioxidant tests, including DPPH radical-scavenging, nitric oxide-scavenging, superoxide anion radical-scavenging, and ABTS radical-scavenging assays, and superoxide dismutase (SOD)-like activity and reducing power analysis, along with the determination of total phenolic and flavonoid contents. Both the extracts showed strong antioxidant activities by these testing methods. Ulmus davidiana root extract possessed strong reducing power and nitric oxide-scavenging activity, and high scavenging activities against free radicals including the superoxide anion, and the ABTS and DPPH radicals, but a weaker scavenging activity of SOD. In contrast, the Ulmus davidiana bark extract exhibited a strong SOD-like activity, but all the other activities were weak. It was observed that the total phenolic and flavonoid contents of the Ulmus davidiana root extract were higher than those of the Ulmus davidiana bark extract.

• Natural Product Sciences
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• 제16권3호
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• pp.143-147
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• 2010

The chromatographic separation of a methanol extract of Artemisia princes led to the isolation of two sesquiterpene lactones, artecanin (1) and canin (2), together with a flavonoid, eupatilin (3). Their structures were determined by 1D, 2D-NMR and MS data analysis. All of the isolates were evaluated for their potential to inhibit the LPS-induced production of nitric oxide in murine macrophage RAW 264.7 cells. Compounds 1 - 3 inhibited nitric oxide production with $IC_{50}$ values of 19.5, 20.4 and 25.1 ${\mu}M$, respectively.

• Archives of Pharmacal Research
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• 제27권4호
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• pp.442-448
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• 2004

Wogonin (5,7-dihydroxy-8-methoxyflavone) is a down-regulator of cyclooxygenase-2 and inducible nitric oxide synthase expression, contributing to anti-inflammatory activity in vivo. For further characterization of modulatory activity on ploinflammatory gene expression in vivo, the effect of wogonin was examined in this experiment using animal models of skin inflammation. By topical application, wogonin inhibited an edematic response as well as ploinflammatory gene expression against contact dermatitis In mice. Wogonin inhibited ear edema ($19.4-22.6\%$) at doses of $50-200\;{\mu}g$/ear and down-regulated interleukin-$1{\beta}$ induction ($23.1\%$) at $200{\mu}g$/ear in phenol-induced simple irritation. Wogonin ($2{\times}50-2{\times}200{\mu}g$/ear) also inhibited edematic response ($51.2-43.9\%$) and down-regulated ploinflammatory gene expression of cyclooxygenase-2, interleukin-$1{\beta}$, interferon-$\gamma$, intercellular adhesion molecule-1 and inducible nitric oxide synthase with some different sensitivity against picryl chloride-induced delayed hypersensitivity reaction. All these results clearly demonstrate that wogonin is a down-regulator of ploinflammatory gene expression in animal models of skin inflammation. Therefore, wogonin may have potential for a new anti-inflammatory agent against skin inflammation.

• Archives of Pharmacal Research
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• 제27권7호
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• pp.751-756
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• 2004

Flavonoids have been demonstrated to exhibit a wide range of biological activities including anti-inflammatory and neuroprotective actions. Although a significant amount of flavonoids has been identified to be present as glycosides in medicinal plants, determinations of the biological activities of flavonoids were mainly carried out with aglycones of flavonoids. Therefore, the exact role of the glycosidation of flavonoid aglycones needs to be established. In an attempt to understand the possible role of glycosidation on the modulation of the biological activities of flavonoids, diverse glycosides of kaempferol, quercetin, and aromadendrin were examined in terms of their anti-inflammatory activity determined with the suppression of lipopolysaccharide (LPS)-induced nitric oxide (NO) production in BV2 microglial cells. The results indicated that glycosidation of aglycones attenuated the suppressive activity of aglycones on LPS-induced NO production. Although attenuated, some of glycosides, depending on the position and degree of glycosidation, maintained the inhibitory capability of LPS-induced NO production. These findings suggest that glycosidation of flavonoid aglycones should be considered as an important modulator of the biological activities of flavonoids.

• 한국약용작물학회지
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• 제19권5호
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• pp.368-372
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• 2011

In this study, we investigated on antioxidative activity and nitric oxide production inhibitory activity of various solvent extracts of Lespedeza bicolor. The total polyphenol content of the methanol extract was 192.6 mg/g and flavonoid content of the acetone extract was 40.6 mg/g, as the highest content. In DPPH radical scavenging ability, $SC_{50}$ values of the ethanol and methanol extract were exhibited $0.69mg/m{\ell}$ and $0.89mg/m{\ell}$, respectively. However, in nitric oxide(NO) scavenging ability, $SC_{50}$ values of the acetone was exhibited $0.72mg/m{\ell}$ as the highest activity. Moreover, the acetone extract showed strong NO production inhibitory effect in lipopolysaccharide(LPS)-stimulated Raw 264.7 cell. In the cytotoxicity measurement by MTT assay, the extracts were exhibited Raw 264.7 cell viabilities of 92.57~129.04% as nontoxic result in concentration of $65{\sim}650{\mu}g/m{\ell}$. As a result, the acetone extract of L. bicolor could be applicable to functional materials for anti-inflammatory related fields.

• Natural Product Sciences
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• 제10권1호
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• pp.1-10
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• 2004

Plant flavonoids possess anti-inflammatory activity in vitro and in vivo. Although the action mechanisms are not fully understood, recent studies have clearly shown that certain flavonoids, especially flavone derivatives, express their anti-inflammatory activity at least in part by modulation of proinflammatory gene expression such as cyclooxygenase-2, inducible nitric oxide synthase and various cytokines. This review summarizes the recent findings of flavonoids modulating expression of proinflammatory molecules.