Experimental Study On Anti-Asthma Action Of The Cortex Mori Extract

Objective: Cortex Mori was the root bark of mulberry tree and has been used as an antiphlogistic, diuretic, and expectorant in herbal medicine. Previous studies have demonstrated that Cortex Mori had inhibitory effects on the compound 48/80 induced degranulation and histamine release from peritoneal mast cells in rat. The purpose of this study was to determine whether Cortex Mori could inhibit the ovalbumin (OVA)-induced late asthmatic reaction in mice.Methods: BALB/C mice were randomly divided into 6 groups, normal control (group A), model (group B), Cortex Mori pretreated before sensitization (group C) , Cortex Mori pretreated before challeng (group D), Cortex Mori pretreated before sensitization and challeng (group E), Cortex Mori group (group F), each group had 10 mice. Group B mice sensitized by intraperitoneal injection with 50μg of OVA and 1 mg aluminum hydroxide in 200ul of 0.9% sterile saline on the day 1^st and day 7^th . Then were challenged with aerosolized OVA (1.0% 15ml) for 20 min on the day 14^th, day 21^st, day 22^nd and day 23^rd. The mice were pretreated by inhalations of the aerosoled Cortex Mori (1 mg/ml) at before sensitization or before challenge or before 1h OVA sensitization and challenge. Bronchia- lveolar lavage fluid (BALF) and peripheral blood were collected on the day 24^th, and examined the quantity of eosinophils, neutrophils, mononuclear cells, lymphocytes and macrophage by Diff-quik stain and the infection circumstance of lung by Hematoxylin-eosin and congo-red stain.Results: (1)The cell changes in BALF : There were significantly increased (p<0.01) eosinophils, neutrophils and lymphocytes in group A compare with group B, were decreased (p<0.01) remarkably eosinophils and neutriphils and decreased (p<0.05) lymphocytes in group B and C compare with group B, were decreased (p<0.01) significantly eosinophils, lymphocytes and neutropilsin in group E compare with group B, were decreased remarkably (p<0.05) eosinophils in group E compare with group C and D. The number of cell between group F and group A was similar; there were not significant changes of macrophage. (2) The cell changes in peripheral blood : In peripheral blood there were significantly increased (p<0.01) eosinophils in group F compare with group A, were decreased remarkably (p<0.05) eosinophils in group C, D, and E compare with group B, were decreased significantly eosinophils (p<0.05) in group E and C compare with group D. There were not significant changes between group F and group A. (3) In group C, D and E : The extract of Cortex Mori not only have effects of inhibition on increasing of eosinophils, lymphocytes and neutropil in BALF, but also have effects of inhibition on increasing of eosinophils in peripheral blood. (4) Histology observation showed that the extract of Cortex Mori could significantly decrease alteration of pathematology in air duct and lung interstitial substance.Conclusion: From the results of this study, it is suggested that Cortex Mori with an activity to inhibits the OVA-induced bronchial asthma in mice.