Some medicinal plants with antiasthmatic potential:a current status

Asthma is a common disease that is rising in prevalence worldwide with the highest prevalence in industrialized countries.Asthma affect about 300 million people worldwide and it has been estimated that a further 100 million will be affected by 2023.Since the ancient times,plants have been exemplary sources of medicine.Current asthma therapy lack satisfactory success due to adverse effect,hence patients are seeking complementary and alternative medicine to treat their asthma.Ayurveda and other Indian literature mention the use of plants in various human ailments.India has about 43 000 plant species and among them several thousand are claimed to possess medicinal properties.Researches conducted in the last few decades on the plants mentioned in ancient literature or used traditionally for asthma have shown antiasthmatic,antihistaminic and antiallergic activity.This review reveals that some plants and their extract have antiasthmatic,antihistaminic,anticholinergic and antiallergic activity.

Pharmacological evaluation of smooth muscle relaxant and cardiac-modulation potential of Phyla nodiflora in ex-vivo and in-vivo experiments

Objective: To investigate the pharmacological basis of its uses of Phyla nodiflora(P. nodiflora) for the treatment of anomalies predominantly by smooth muscle containing tissues such as gastrointestinal/vascular/broncho spasm and cardiovascular modulation.Methods: The crude hydroalcoholic extract of P. nodiflora(Pn.Cr) and its fractions were evaluated on isolated rabbit jejunum, rat trachea, aorta and atrium. To access the contractile or relaxant effects of testing materials, the tissues were mounted in isolated organ bath and responses were recorded with transducers coupled with data acquisition system.BALB/c mice were challenged with castor oil for the assessment of in-vivo antidiarrheal activity. Normotensive rats were used for in-vivo hypotensive study.Results: Hydroalcoholic extract of Pn.Cr at variable concentrations inhibited the natural spontaneous rhythm and 80 mmol/L K^+ mediated contractions in isolated segment of jejunum with EC_(50) values of 3.18 and 1.91 mg/mL respectively. Verapamil, a Ca^(2+) channel blocker, demonstrated akin pattern in jejunum and therefore possibly suggesting calcium blocking activity. On isolated rat tracheal tissue, Pn.Cr showed relaxation of high-K^+and carbachol mediated contractions(EC_(50) values: 1.24 and 2.42 mg/mL). Pn.Cr treatment relaxed the rat aortic ring in a cumulative doses with high-K^+ and phenylephrine-induced contractions(EC_(50) values 0.25 and 0.92 mg/mL). Activity based fractionation of Pn.Cr showed that dichloromethane fraction was more potent for relaxing the tissues spasm compared to aqueous fraction. In-vivo experiments, significant protection by Pn.Cr(P < 0.05) was observed in castor oil-induced diarrhea(50–500 mg/kg)whereas hypotensive effect in anesthetized rats was seen at the dose range of 1–10 mg/kg of Pn.Cr(P < 0.05).Conclusion: This study suggests the blockage of calcium channel in the smooth muscles as a pharmacological application to make usage of P. nodiflora in the management of diarrhea, asthma and hypotensive effect.

Studies on the anti-asthmatic and antitussive properties of aqueous leaf extract of Bryophyllum pinnatum in rodent species

Objective:To evaluate the antiasthmatic and antitussive properties of the aqueous leaf extract of Bryophyilum pinnatum {B.pinnatum)(BP) Lam.Methods:Ovalbiunin-sensilized guinea pigs which were treated with BP for 21 consecutive days were exposed to 0.2%histamine aerosol in a glass chamber.Mucus viscosity,white blood cell and lymphocyte counts and tracheal wall morphometry were measured.Bouts of cough were counted pre and post acute exposure of extract-treated(X7 d) guinea pigs to 7.5%citric acid aerosol in a chamber.Phenol red expectoration was estimated in mice after 7 d of daily administration of BP.Results:Doses of 200 and 400 mg/kg/day(×21 d) BP significantly increased the time for guinea pigs to experience preconvulsive dyspnoea.BP and salbutamol(0.5 mg/kg/day×21 d) reduced mucus viscosity in the sensitized group to values comparable with controls.White blood cell,lymphocyte counts and tracheal morphometry were not significantly altered.Both doses of BP also significantly reduced the bouts of cough but only 400 mg/kg/day significantly inhibited the amount of phenol red secreted.Conclusions:BP has demonstrated antiasthmatic and antitussive properties in these rodent models.These properties may underscore its use in Nigerian ethnomedicine.