The in Vitro Study of Inhibitory Properties of Triterpenes fromExtracted Euphorbia Plant on Cyclooxygenase-1 Activity and the Evaluation of their Cytotoxicity on L-929 Cell Lines

Triterpenes could exert anti-inflammatory properties. The aim of this study was to evaluate the inhibitory activities of cycloartan triterpene derivatives extracted from Euphorbia with names as; cycloartan-24-methylene3-ol(1), cycloartan-23-ene-3,25-diol(2), cycloartan-23-ene-25-methoxy-3-ol (3) and cycloartan-24-ene-3-ol (4) on cyclooxygenase-1(cox-1) activity. This is an experimental study. The cyclooxygenase enzyme was extracted from platelets and peripheral blood mononuclear cells by Ficoll-Paque density gradient. The inhibitory activities of the compounds were assessed by measuring the peroxidase activity of enzyme by End point Enzyme activity assay. The inhibitory effects of the compounds were examined using logarithmic concentrations of them (1, 10,100 µg/ml). The cytotoxicity of each compound was measured using Cell Survival of L-929 cell lines by MTT assay. The cox-1 inhibitory effect of compound 3 was very weak at a concentration more than 100 mg/ml and IC50>100 (mg/ml). The results revealed that; the compounds 1, 2 and 4 at concentrations (1, 10, and 100 µg/ml) demonstrated the acceptable inhibitory effects for the cox-1 enzyme with the IC50 of 9.65, 16.51 and 9.22 (mg/ml) compared with SC-560 control, respectively. The toxicity effects of compounds compared with Doxorubicin on the survival of L-929 cells, revealed that the IC50 of the 1, 2, 3, and 4 compounds are equal to 64.88, 64.47, >60 and 66.23 (mg/ml), respectively. Cycloartan triterpene derivatives extracted from Euphorbia plant could have inhibitory activities on cox-1 enzyme. The cytotoxicity study showed that these compounds probably at low concentrations could be useful to treat the diseases caused by increasing cycloxygenese-1 activity.