RESUMEN
Turnera ulmifolia is a plant popularly known in Brazil and South America as chanana. Some species of Turnera are widely used in folk medicine for different types of inflammatory diseases. In this study, the preventive intestinal antiinflammatory activity of a lyophilized infusion obtained from the aerial parts of T. ulmifolia was tested in the trinitrobenzenesulphonic acid (TNBS) model of rat colitis. The results obtained revealed that pretreatment to colitic rats with the extract, at 250 and 500 mg/kg, significantly attenuated the colonic damage induced by TNBS. This beneficial effect was associated with an improvement in the colonic oxidative status, since the infusion prevented the glutathione depletion that occurred as a consequence of the colonic inflammation. On the other hand, this antioxidant activity was confirmed in in vitro studies. In conclusion, the preventive effect exerted by the lyophilized infusion of T. ulmifolia in the TNBS model of rat colitis is probably related to its antioxidant properties, due to its flavonoids content.
Asunto(s)
Antiinflamatorios no Esteroideos/farmacología , Colitis/tratamiento farmacológico , Fármacos Gastrointestinales/farmacología , Fitoterapia , Extractos Vegetales/farmacología , Turnera , Administración Oral , Animales , Antiinflamatorios no Esteroideos/administración & dosificación , Antiinflamatorios no Esteroideos/uso terapéutico , Colitis/inducido químicamente , Colitis/patología , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Femenino , Liofilización , Fármacos Gastrointestinales/administración & dosificación , Fármacos Gastrointestinales/uso terapéutico , Componentes Aéreos de las Plantas , Extractos Vegetales/administración & dosificación , Extractos Vegetales/uso terapéutico , Ratas , Ratas Wistar , Ácido TrinitrobencenosulfónicoRESUMEN
We investigated the antiulcerogenic activity of pyrrolizidine alkaloids (PAs) integerrimine, retrorsine, senecionine, usaramine and seneciplhylline, an alkaloidal extract obtained from Senecio brasiliensis. The PA extract demonstrated significantly activity in both, acute and chronic gastric ulcers on rats. The effects of PA extract were dose dependent. The mechanisms implicated on this activity were evaluated by determination of gastrin plasma levels in rats subjected to the acute treatment with PA extract and by expression of mRNA of Epidermal Growth Factor (EGF) after chronic treatment with this extract. The results showed that the PA extract increased both the levels of gastrin and the expression of EGF on these animals. Moreover, the histological examinations showed a reduction of exfoliation of superficial cells, hemorrhages and blood cell infiltration. We concluded that the PAs showed an important and qualitative antiulcerogenic activity mediated by increase in gastrin secretion and mRNA expression of EGF.
