Suppressive effect of inducible nitric oxide synthase (iNOS) expression by the methanol extract of Actinodaphne lancifolia.
Nitric oxide (NO) produced by inducible nitric oxide synthase (iNOS) has played a crucial role in various pathophysiological processes including inflammation and carcinogenesis. Therefore, the inhibitors of NO synthesis or iNOS gene expression have been considered as potential anti-inflammatory and cancer chemopreventive agents. In our continuous search for iNOS inhibitors from natural products we have evaluated indigenous Korean plant extracts using an assay for inhibition of nitric oxide formation on lipopolysaccharide (LPS)-activated mouse macrophage RAW 264.7 cells. As a result, the methanolic stem extract of Actinodaphne lancifolia showed an inhibitory activity of NO production in a dose-dependent manner (IC50 = 2.5 microg/ml). Additional study demonstrated that the extract of Actinodaphne lancifolia significantly suppressed the iNOS protein and gene expression in a dose-dependent manner. These results suggest that Actinodaphne lancifolia could be a potential candidate for developing an iNOS inhibitor from natural products. Further elucidation of active principles for development of new cancer chemopreventive and/or anti-inflammatory agents could be warranted.
Kim
Youngleem
Y
College of Pharmacy, Ewha Womans University, Seodaemun-ku, Seoul, Korea.
Min
Hye-Young
HY
Park
Hyen-Joo
HJ
Lee
Eun-Jin
EJ
Park
Eun-Jung
EJ
Hwang
Hye-Jin
HJ
Jin
Changbae
C
Lee
Yong Sup
YS
Lee
Sang Kook
SK
D000818:Animals; D015153:Blotting, Western; D017931:DNA Primers; D004305:Dose-Response Relationship, Drug; D020128:Inhibitory Concentration 50; D019770:Lauraceae; D008070:Lipopolysaccharides; D008264:Macrophages / Q000187:drug effects* / Q000201:enzymology; D051379:Mice; D019001:Nitric Oxide Synthase / Q000037:antagonists & inhibitors* / Q000096:biosynthesis / Q000235:genetics; D052247:Nitric Oxide Synthase Type II; D008517:Phytotherapy; D010936:Plant Extracts / Q000008:administration & dosage / Q000494:pharmacology* / Q000627:therapeutic use; D018547:Plant Stems; D020133:Reverse Transcriptase Polymerase Chain Reaction
D017931:DNA Primers; D008070:Lipopolysaccharides; D010936:Plant Extracts; D019001:Nitric Oxide Synthase; D052247:Nitric Oxide Synthase Type II; C496317:Nos2 protein, mouse