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Gentiolactone, a secoiridoid dilactone from Gentiana triflora, inhibits TNF-?, iNOS and Cox-2 mRNA expression and blocks NF-?B promoter activity in murine macrophages.

ABSTRACT:

Background

Gentian roots have been used as a herbal medicine because of their anti-inflammatory activities. However, the molecular mechanisms of these anti-inflammatory effects remain to be completely explained.

Methods and findings

Here, we investigated anti-inflammatory effects of gentian roots and showed that root extracts from Gentiana triflora inhibited lipopolysaccharide (LPS)-induced expression of TNF-? in RAW264.7 cells. The extracts also contained swertiamarin and gentiopicroside, which are the major active compounds of gentian roots; however, neither compound had any effect on LPS-induced TNF-? production in our test system. We isolated gentiolactone as an inhibitor of TNF-? production from the extracts. Gentiolactone also inhibited LPS-induced inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (Cox-2) expression at the mRNA level. Moreover, gentiolactone suppressed NF-?B transcriptional activity without inhibition of I?B degradation or NF-?B nuclear transport.

Conclusions

Our results indicate that inhibition of TNF-?, iNOS and Cox-2 expression by gentiolactone is one of the mechanisms of the anti-inflammatory properties of gentian roots.

SUBMITTER: Yamada H

PROVIDER: S-EPMC4244148 | biostudies-literature | 2014

REPOSITORIES: biostudies-literature

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Gentiolactone, a secoiridoid dilactone from Gentiana triflora, inhibits TNF-α, iNOS and Cox-2 mRNA expression and blocks NF-κB promoter activity in murine macrophages.

Yamada Hidetoshi H Kikuchi Sayaka S Inui Tomoki T Takahashi Hideyuki H Kimura Ken-ichi K

PloS one 20141125 11

<h4>Background</h4>Gentian roots have been used as a herbal medicine because of their anti-inflammatory activities. However, the molecular mechanisms of these anti-inflammatory effects remain to be completely explained.<h4>Methods and findings</h4>Here, we investigated anti-inflammatory effects of gentian roots and showed that root extracts from Gentiana triflora inhibited lipopolysaccharide (LPS)-induced expression of TNF-α in RAW264.7 cells. The extracts also contained swertiamarin and gentiop ...[more]

PMID: 25423092

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