Abstract

Anti-allergics, including mast cell stabilizers, are used together with other anti-inflammatory drugs in the management of asthma, so as to prevent the release of pre-formed inflammatory mediators upon allergen exposure. This study was aimed at investigating the mast cell stabilizing and anti-anaphylactic effects of a 70% hydro-ethanolic extract of Scoparia dulcis (SDE) in murine models upon exposure to a known allergen. In vitro cytological and histological studies were conducted on guinea-pigs peritoneal cells and mesenteric tissues, respectively, to establish mast cell stabilization effect of the extract on compound 48/80-induced mast cell degranulation. The ability of SDE to protect mice against anaphylactic shock induced by compound 48/80 was also assessed. Preliminary phytochemical analysis was conducted on the extract using standard phyto-analytic procedures. Phytochemical screening showed the presence of tannins, alkaloids, glycosides, saponins, steroids and phenolic compounds. SDE showed significant inhibition (P ≤ 0.001) against compound 48/80-induced degranulation in both the peritoneal and mesenteric mast cells of guinea-pigs (comparable to sodium cromoglycate and ketotifen fumarate). SDE also delayed the onset of symptoms of anaphylaxis in mice induced with compound 48/80, as well as reduced their mortality rate. The hydro-ethanolic extract of S. dulcis has significant mast cell stabilizing and anti-anaphylactic activities; making it a better adjunct in asthma management.

Key words: Anti-allergenic, Mast cell stabilization, Anti-anaphylactic, Compound 48/80, Scoparia dulcis.