Histamine and Beta-Hexosaminidase Inhibitory Effects of Crude Alkaloid from Kopsia arborea Blume in RBL-2H3 Cell LinesAuthor(s): Shahari MS, Husain K*, Kumolosasi E and Rajab NF
Kopsia arborea Blume is one of the plants in the Apocynaceae family, found in southeastern Asia and Malaysia. It has been used widely in traditional medicines. Extracts and pure isolates of Kopsia species have been reported to exhibit various biological activities. In this study, crude alkaloid derived from different parts of K. arborea was evaluated for their inhibitory activity on histamine and beta-hexosaminidase release in rat basophilic leukemic (RBL-2H3) cells. The effect of K. arborea on histamine, beta-hexosaminidase release and beta-hexosaminidase activity in RBL-2H3 cell was determined by using sandwich enzyme-linked immunosorbent assay (ELISA). On the other hand, cytotoxic effect of crude alkaloid in RBL-2H3 cell was evaluated by standard 3-(4, 5-dimetiltiazol-2-Yl)-2, 5-difeniltetrazolium (MTT) assay. The results showed that all samples significantly inhibit (p ≤ 0.001) the histamine release in RBL-2H3 cell except K. arborea (roots). However, % inhibition of histamine release demonstrated by crude alkaloid extracted from K. arborea leaves was higher as compared to ketotifen fumarate that acts as positive control. Meanwhile, crude alkaloid extracted from K. arborea (roots) exhibited the highest inhibition of beta-hexosaminidase release and activity than ketotifen fumarate. These results indicated that crude alkaloid from this plant consist of bioactive compounds which have the ability to inhibit mast cell degranulation via inhibition of histamine and beta-hexosaminidase release and have potential to provide as alternative anti-allergic agent.