Phytopharmacological Evaluation of The Leaves of Lagenaria Siceraria (Molina) Standley With Reference to Anti - Asthmatic Activity

Abstract

Lagenaria siceraria (Mol.) Standley (Cucurbitaceae) commonly known as bottle gourd is a climbing perennial herb cultivated as a vegetable in tropical countries and has been used traditionally for many disorders like asthma bronchitis, inflammation, leprosy, jaundice etc. Pharmacognostical, physicochemical and pharmacological parameters for the leaves of Lagenaria siceraria were studied. The quantitative microscopical parameters like stomatal index, stomatal number, palisade ratio, vein islet vein termination numbers of the fresh leaves of L. siceraria were also evaluated in order to set forth the quantitative standards. The physico chemical parameters like total ash, water soluble ash, acid insoluble ash, water soluble extractive value, alcohol soluble extractive value, loss on drying were evaluated for the leaf powder. The powdered sample of leaves of L. siceraria was extracted with water and methanol to yield aqueous extract (26%) and methanolic extract (17%). These extracts were subjected to determination of total phenolic and total flavonoid content. The aqueous extract contained the highest amount of phenol and the methanolic extract contained the highest amount of the flavonoids compared to the aqueous extract. Both aqueous and methanolic extract of the L. siceraria leaf were used for evaluating the anti asthmatic, anti allergic and anti inflammatory activity. The aqueous extract showed the bronchodilatory effects on histamine and acetyl choline induced bronchospasm in guinea pigs in dose dependent manner with maximum activity at the dose of 300 mg/ kg. The inhibition of aqueous and methanolic extract against histamine and acetyl choline induced contractions in isolated guinea pig ileum were studied at the dose of 100 μg/ml where methanolic extract showed more potent inhibition of contraction compared to aqueous extract and it was comparable to the standard aminophylline. At the dose of 200μg/ml both the extracts almost inhibited the ileum contraction. Both the extracts showed the anti allergic potential against mast cell degranulation in rat mesentery. The aqueous and methanolic extracts showed maximum protection at the doses of 30μg/ml where methanolic extract showed percent protection even more than the standard ketotifen showing potent mast cell stabilizing activity. The anti inflammatory effects of both the extracts were explored using inhibition against compound 48/80 induced paw edema in mice. The aqueous extract showed maximum inhibition at the dose of 100 mg/ kg which was higher compard to methanolic extract. However, the drug extracts did not show potent anti inflammatory effects. The leaf of L. siceraria was found rich in terpenoids and flavonoids which have been researched extensively for their anti asthmatic, anti allergic and anti inflammatory effects. Thus, it can be concluded that the bronchodilatory, antiallergic and anti inflammatory effects of the drug can be attributed to these constituents. From the above results, it can also be concluded that the drug possesses anti histaminic, anti muscarinic, anti inflammatory, mast cell stabilization and direct relaxant. Thus, the traditional use of L siceraria leaves in the treatment of asthma has been explored scientifically.