Antinociceptive activity of discretamine isolated from Duguetia moricandiana.

The phytochemical study of Duguetia moricandiana Mart. (Annonaceae) yielded the isolation of the alkaloid which was identified by spectral analysis as discretamine. The evaluation of antinociceptive activity carried out by the acetic acid-induced writhing, formalin and hot plate tests in mice, suggests a potent antinociceptive effect. Discretamine (5, 10 and 20 mg kg⁻¹, i.p.) significantly reduced the number of writhes similarly at all doses tested and the number of paw licks during the first phase of formalin test when compared to control. The effect of discretamine on hot plate response provides a confirmation of its central effect. These results indicate antinociceptive properties of this alkaloid.

The triterpenoid lupeol attenuates allergic airway inflammation in a murine model.

Asthma is a chronic inflammatory disease of the airways associated with a Th2 immune response. Despite their side effects, corticosteroids are the most used and effective drugs for treatment of asthma. In this work we investigated the efficacy of lupeol, a triterpenoid isolated from Lonchocarpus araripensis [corrected] Benth. (Fabaceae), in the treatment of bronchial asthma in BALB/c mice immunized with ovalbumin. Administration of lupeol caused the reduction of cellularity and eosinophils in the bronchoalveolar lavage fluid. Treatment with lupeol also reduced the production of mucus and overall inflammation in the lung. Levels of Type II cytokines IL-4, IL-5 and IL-13 were significantly reduced in mice treated with lupeol, an effect that was similar to that observed in dexamethasone-treated mice. In contrast, IgE production was not significantly altered after treatment with lupeol. In conclusion, our results demonstrate that lupeol attenuates the alterations' characteristics of allergic airway inflammation. The investigation of the mechanisms of action of this molecule may contribute for the development of new drugs for the treatment of asthma.