Byline: P. Patel, K. Patel, T. Gandhi
The present investigation was undertaken to evaluate the bronchodilating effect and bronchial hyperreactivity of alcoholic extract of Taxus baccata Linn. (AET) leaves in experimental animals. Bronchodilator activity of AET was studied on the histamine and acetylcholine aerosol induced bronchospasm in guinea pigs and bronchial hyperreactivity was studied on bronchoalveolar lavage fluid (BALF) in the egg albumin sensitized guinea pigs and by histopathological studies. In vitro mast cell stabilizing activity was studied using compound 48/80 as a degranulating agent. Treatment with AET (200 and 400 mg/kg, p.o., for 7 days) showed significant protection against histamine and acetylcholine aerosol induced bronchospasm in guinea pigs. Significant decrease in the total leukocyte and differential leukocyte count in the BALF of the egg albumin sensitized guinea pigs was observed by administration of AET (200 and 400 mg/kg, p.o., for 15 days). AET dose dependently protected the mast cell disruption induced by compound 48/80. These results suggest that AET not only has bronchodilating activity but also decreases bronchial hyperreactivity by decreasing the infiltration of inflammatory cells in the airway and inhibiting the release of histamine like mediators from the mast cell by stabilizing it.
Asthma is one of the most common disorders encountered in clinical medicine in both children and adults, characterized by inflammation of the airway that is central to airway dysfunction. It is known that asthma can be triggered by various factors: allergens, drugs, respiratory infection, dust, cold air, exercise, emotions, occupational stimuli, chemicals, histamine, etc. [sup] Histological examination of bronchial biopsies and cytology of bronchoalveolar lavage fluid (BALF) have demonstrated infiltrating inflammatory cells in the tracheobronchial mucosa and airway lumen of patients with asthma, even those with mild disease. [sup], The influx of inflammatory cells is accompanied by marked and characteristic pathophysiological changes to the airways, including thickening of the airway wall, which have been implicated in the restriction of airflow and the development of airway hyperresponsiveness. [sup] The disease statistics clearly necessitates the increasing need for drugs targeting the mechanisms involved in eosinophil and neutrophil activation and accumulation, for the management of asthma. Glucocorticosteroids are the only drugs currently available that effectively reduce airway inflammation in asthma. [sup]
As a result, there is high prevalence of usage of complementary and alternative medicines for treatment of this disease. [sup] Ayurveda, an ancient system of Indian medicine, has recommended a number of drugs from indigenous plant sources for the treatment of bronchial asthma and allergic disorders. [sup] Taxus baccata Linn. (Taxaceae) is an evergreen tree, usually 6 m in height and 1.5-1.8 m in width, found in the temperate Himalayas at an altitude between 1800 and 3300 m and in the hills of Meghalaya and Manipur at an altitude of 1500 m. [sup] T. baccata has been used in the Ayurvedic system for the treatment of cancer, diarrhea, asthma, hemoptysis and also used as carminative, expectorant, stomachic, etc. [sup] T. baccata leaves are reported to be used in traditional medicine as abortifacient, antimalarial, antirheumatic and for...