Abstract:
Context: Polyscias fruticosa (L.) Harms (Araliaceae) is used as a traditional remedy for asthma in
Ghana.
Objective: The objective of this study is to establish the anti-asthmatic property and a possible
mode of activity of an ethanol leaf extract of P. fruticosa (PFE).
Materials and methods: The time (min) for pre-convulsive dyspnea, and time for recovery, after
sensitization with 150 mg OVA and induction of bronchospasm with 1% acetylcholine or histamine
in normal, and 100, 250, and 500 mg/kg PFE-treated Dunkin Hartley guinea pigs, were recorded.
Atropine (0.1 mg), mepyramine (0.1 mg), and PFE (1 mg) effect on a contractile response of
2.0 10 2 mg/ml acetylcholine and 5.8 10 2 mg/ml histamine on the isolated guinea pig ileum
was investigated. Cytological and histological studies were conducted using guinea pig peritoneal
mast cells and mesenteric cells, respectively, to establish PFE effect on compound 48/80-induced
mast cell degranulation.
Results: PFE (100–500 mg/kg) prolonged the onset of pre-convulsive dyspnea by 76.1–180.2%
(p 0.01–0.001), and decreased recovery time by 71.9–78.5% (p 0.01–0.001). It also enhanced
percentage protection against histamine-induced bronchospasm by 15.8–80.1-fold (p 0.05–0.01),
and decreased percentage recovery time 2.5–3.3-fold (p 0.05–0.01). PFE significantly inhibited
(60.4 ± 8.3%) contractile responses of histamine and produced significant inhibition (56–79%:
p 0.001) of mast cell degranulation.
Conclusion: PFE has anti-asthmatic, antihistaminic, and mast cell stabilization effect making it useful
in traditional asthma management.
