%0 Journal Article %T Inhibition of Nitric Oxide Production and Proinflammatory Cytokines by Several Medicinal Plants %J Iranian Journal of Immunology %I Shiraz Institute for Cancer Research %Z 1735-1383 %A Amirghofran, Zahra %A Malek-Hosseini, Saeed %A Golmoghaddam, Hossein %A Kalantar, Fathollah %A Shabani, Mehdi %D 2011 %\ 09/01/2011 %V 8 %N 3 %P 159-169 %! Inhibition of Nitric Oxide Production and Proinflammatory Cytokines by Several Medicinal Plants %K Cytokines %K medicinal plants %K Nitric oxide %R %X Background: A number of medicinal plants have been used to treat various immunological diseases. Nitric oxide (NO) has an important regulatory role in the various types of inflammatory processes. Objective: To investigate the NO modulatory activity of the extracts of several medicinal plants native to Iran including Dracocephalum kotschyi, Linum persicum, Dionysia termeana, Salvia mirzayanii, Ferulago angulata and Euphorbia cheiradenia. Methods: The methanolic extracts of the plants were prepared and examined for their effects on the NO production by lipopolysaccharide-stimulated mouse macrophages. The level of TNF-α and IL-1β proinflammatory cytokines in the macrophage culture were detected using enzyme-linked immunosorbent assay. Results: All the extracts at concentration of 50 μg/ml demonstrated a significant decrease in NO production (p<0.001) after a 24-hour treatment. This inhibitory effect was also seen after 48 hours. Among the extracts, L. persicum was the strongest extract in reducing the NO production at 1 μg/ml after both 24 and 48-hours (nearly 100% inhibition, p<0.001). S. mirzayanii extract with 66.2 ± 8% inhibition at 50 μg/ml, showed the mildest effects in 48 hour culture. In cytokine release determination, the extract of L. persicum significantly inhibited both TNF-α and IL-1β cytokines production by stimulated macrophages (p<0.001). D. kotschyi, D. termeana and F. angulata decreased secretion of IL-1β from the cells. Conclusion: These results indicate the presence of anti-inflammatory and macrophage inhibitory substances in these plants. %U https://iji.sums.ac.ir/article_17021_ec634e2b032f8b41d8c33e1cf4f3fef9.pdf