ABSTRACT
Several species of Senna are well known for their therapeutic properties, being used in folk medicine to treat throat inflammation and constipation. In this regard, the anti-inflammatory, laxative and intestinal motility effects of different extracts of Senna macranthera (Colladon) H. Irwin and Barneby leaves were determined. The hexane extract significantly reduced carrageenan-induced paw oedema in rats in a manner similar to that of sodium diclofenac. A laxative effect was observed for the methanolic and hexane extracts comparative to the standard drug bisacodyl; however, only the hexane extract increased the intestinal motility in the studied period. Moreover, the extracts were evaluated for their antioxidant activity and the ethyl acetate extract presented a pronounced activity comparable to the standard rutin. Phytochemical screening was also performed and phenolic compounds like flavonoids, tannins and coumarins were observed in all extracts except for the hexane extract, which instead presented anthrones, triterpenes and steroids in its composition. The HPLC profile showed the presence of the anthraquinone emodine in all tested extracts.
Subject(s)
Anti-Inflammatory Agents/pharmacology , Gastrointestinal Motility/drug effects , Laxatives/pharmacology , Plant Extracts/pharmacology , Senna Plant/chemistry , Animals , Anti-Inflammatory Agents/chemistry , Antioxidants/chemistry , Antioxidants/pharmacology , Carrageenan/toxicity , Chromatography, High Pressure Liquid , Coumarins/isolation & purification , Drug Evaluation, Preclinical/methods , Edema/chemically induced , Edema/drug therapy , Flavonoids/analysis , Flavonoids/chemistry , Flavonoids/isolation & purification , Laxatives/chemistry , Male , Plant Extracts/chemistry , Plant Leaves/chemistry , Plants, Medicinal/chemistry , Rats , Rats, Wistar , Tannins/isolation & purificationABSTRACT
ETHNOPHARMACOLOGICAL RELEVANCE: Leaves of Cecropia pachystachya are described in the folk medicine as possessing antitusive, expectorant, antiasthmatic and hypoglycemic effects. AIM OF THE STUDY: To investigate the hypoglycemic and antioxidant effects of methanolic extract from the leaves of Cecropia pachystachya. The total amount of phenolic and flavonoids compounds was determined and the qualitative composition of the extract was analyzed. MATERIALS AND METHODS: The hypoglycemic effect of the extract was tested in normal, glucose loading and alloxan-induced diabetic rats. The antioxidant activity was assessed by DPPH free radical scavenging and reduction power assays. The total amount of phenolic and flavonoids compounds was determined by Folin-Denis and AlCl(3) reagent method, respectively. The qualitative composition of the extract was analyzed using a HPLC-DAD system. RESULTS: The glucose tolerance test showed that in diabetic rats, the extract caused a significant hypoglycemic effect with a blood glucose reduction of 68% after 12h. The administration of the extract in alloxan-induced diabetic rats also produced a significant reduction in the blood glucose levels at all points being more pronounced at 90min (reduction of 60%). After 120min, no significant difference was observed between the blood levels of the rats treated with the extract and those treated with the standard drugs (metformin and glibenclamide). The extract also presented relevant antioxidant activity with IC50=3.1microg/ml (DPPH assay) and EC50=10.8microg/ml (reduction power). Results were compared with the reference antioxidants quercetin, rutin, and ascorbic acid. The content of flavonoids was 83mg/g plant and that of phenolics was 326mg/g plant. Chlorogenic acid and the C-glycosylated flavones, orientin and isoorientin, were identified in the extract. CONCLUSIONS: In conclusion, the findings showed that the folk medicinal plant Cecropia pachystachya possesses hypoglycemic and antioxidant effects which confirmed the traditional use of the plant in the treatment of diabetes. Chlorogenic acid and the C-glycosylated flavonoids may explain these activities.
