Qiang, D; Zhen, C; Lin-fu, Z; Qian, Z; Mao, H; Kai-sheng, Y
Astragaloside IV, a new cycloartane-type triterpene glycoside extract of Astragalus membranaceus Bunge, has been identified for its potent immunoregulatory, antiinflammatory, and antifibrotic actions. Here we investigated whether astragaloside IV could suppress the progression of airway inflammation, airway hyperresponsiveness, and airway remodeling in a murine model of chronic asthma. BALB/c mice sensitized to ovalbumin (OVA) were chronically challenged with aerosolized OVA for 8 weeks. Astragaloside IV was orally administered at a dose of 50 mg·kg-1·day-1 during each OVA challenge. Astragaloside IV treatment resulted in significant reduction of eosinophilic airway inflammation, airway hyperresponsiveness, interleukin (IL)-4 and IL-13 levels in bronchoalveolar lavage fluid, and total immunoglobulin E levels in serum. Furthermore, astragaloside IV treatment markedly inhibited airway remodeling, including subepithelial fibrosis, smooth muscle hypertrophy, and goblet cell hyperplasia. In addition, the expression of transforming growth factor-β1 in the lung was also reduced by astragaloside IV. These data indicate that astragaloside IV may mitigate the development of characteristic features in chronic experimental asthma. (English) [ABSTRACT FROM AUTHOR] L’astragaloside IV, un nouvel extrait glycoside triterpénique de type cycloartane de Astragalus membranaceus Bunge, est connu pour ses puissantes actions immunorégulatrices, anti-inflammatoires et antifibrosantes. Ici, nous avons examiné si l’astragaloside IV peut supprimer la progression de l’inflammation bronchique, l’hyperréactivité bronchique et le remodelage bronchique dans un modèle murin d’asthme chronique. Des souris BALB/c sensibilisées àl’ovalbumine (OVA) ont été soumises àune provocation chronique àl’OVA en aérosol pendant 8 semaines. L’astragaloside IV a été administré par voie orale àune dose de 50 mg·kg-1·jour-1 durant chaque provocation. Le traitement àl’astragaloside IV a entraîné une réduction significative de l’inflammation bronchique éosinophilique, de l’HB, des taux d’interleukine (IL)-4 et IL-13 dans le liquide de lavage bronchoalvéolaire et des taux d’immunoglobuline E totale dans le sérum. De plus, le traitement a inhibé significativement le remodelage bronchique, y compris la fibrose sous-épithéliale, l’hypertrophie des muscles lisses et l’hyperplasie des cellules caliciformes. L’astragaloside IV a aussi réduit l’expression du facteur de croissance transformant-β1 dans le poumon. Ces résultats indiquent que l’astragaloside IV pourrait atténuer l’apparition d’éléments caractéristiques dans l’asthme expérimental chronique. (French) [ABSTRACT FROM AUTHOR] Copyright of Canadian Journal of Physiology & Pharmacology is the property of NRC Research Press and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts)