Abstract
Diarrhea is the second leading cause of death in children under five years of age globally. Traditional medicinal practices often use plants to manage gastrointestinal issues. Ammodaucus leucotrichus is a medicinal plant that holds significant importance in Moroccan traditional medicine for treating gastrointestinal problems. This study aimed to validate the traditional use of A. leucotrichus by providing scientific evidence for its efficacy. We evaluated the effectiveness of the methanol fraction of A. leucotrichus in alleviating diarrhea and reducing smooth muscle contractions using comprehensive in vivo and in vitro models. In vitro experiments were performed using an isotonic transducer in the jejunum of rats and rabbits. In vivo antidiarrheal effects were evaluated in mice with castor oil-induced diarrhea. The methanol fraction of A. leucotrichus (MFAl) inhibited diarrhea in a dose-dependent manner. It also exhibited spasmolytic activity at doses ranging from 5.5 to 65 μg/ml, with IC(50) values of 43.43 ± 2.63 μg/ml for potassium chloride (KCl) and 28.91 ± 0.43 μg/ml for carbachol (CCh). The obtained spasmolytic activities were comparable to those of a non-competitive antagonist of calcium channels and muscarinic receptors by rightward and downward shifts in the concentration-response curves for calcium and carbachol. Our results demonstrate that, with the addition of nifedipine, the spasmolytic effect of MFAl decreased by 70.11%. This indicates that the spasmolytic effect of MFAl is possibly mediated by the inhibition of Ca(2+) influx. In addition, the presence of hexamethonium significantly modified the relaxation effect of MFAl by 46.20%, indicating that MFAl also acts through nicotinic receptors. These findings support the traditional use of A. leucotrichus for gastrointestinal disorders and highlight the need for further research to develop new anti-diarrheal and anti-spasmodic treatments.