Inducible Nitric Oxide Synthase Inhibitors of Chinese Herbs III.Rheum palmatum
| Autor: | Yi Ju Huang, Lain Tze Lee, Ling-Ling Yang, Lih Geeng Chen, Ching Chiung Wang |
|---|---|
| Rok vydání: | 2002 |
| Předmět: |
Lipopolysaccharides
Nitric Oxide Synthase Inhibitors Emodin Lipopolysaccharide Blotting Western Nitric Oxide Synthase Type II Pharmaceutical Science Anthraquinones Pharmacology Plant Roots Mixed Function Oxygenases Analytical Chemistry Inhibitory Concentration 50 Mice chemistry.chemical_compound Drug Discovery Botany Animals Humans Cytotoxic T cell No production Nitrite Rheum Cells Cultured Chromatography High Pressure Liquid Rheum palmatum biology Macrophages Organic Chemistry Membrane Proteins Chinese herbs biology.organism_classification Isoenzymes Complementary and alternative medicine chemistry Cyclooxygenase 2 Prostaglandin-Endoperoxide Synthases Molecular Medicine lipids (amino acids peptides and proteins) Nitric Oxide Synthase Drugs Chinese Herbal Phytotherapy |
| Zdroj: | Planta Medica. 68:869-874 |
| ISSN: | 1439-0221 0032-0943 |
| DOI: | 10.1055/s-2002-34918 |
| Popis: | In this paper, the effects of bioactive compounds of Rheum palmatum L. on the inhibition of NO production from RAW 264.7 cells were explored. Seven main anthraquinone derivatives were isolated from the root of R. palmatum, and of these, emodin and rhein significantly inhibited nitrite production from lipopolysaccharide (LPS)-activated RAW 264.7 cells. The IC(50) values for inhibition of nitrite production by emodin and rhein were 60.7 and 67.3 microM, respectively. After iNOS enzyme activity was stimulated by LPS for 12 h, treatment with emodin or rhein at 20 microg/ml for 18 h did not significantly inhibit NO production. The data show that the inhibitory activity of emodin and rhein is not due to direct inhibition of iNOS enzyme activity. However, expression of iNOS and the COX-2 protein was inhibited by emodin in LPS-activated RAW 264.7 cells, and PGE(2) production was reduced. Rhein also inhibited LPS-induced iNOS protein expression, but not COX-2 or PGE(2) production. On the other hand, inhibition effects on NO production from RAW 264.7 cells were enhanced and cytotoxic effects decreased by co-treatment with emodin and rhein. In conclusion, emodin and rhein are major iNOS inhibitors of R. palmatum and may possibly serve as bioactive substances for anti-inflammation effects. |
| Databáze: | OpenAIRE |
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