Departamento de Bioquímica - ICB - Universidade Federal de Juiz de Fora, Campus Universitário, Martelos, CEP 36036 900, Juiz de Fora, MG, Brazil.
J Ethnopharmacol. 2010 Apr 21;128(3):629-33. doi: 10.1016/j.jep.2010.01.008. Epub 2010 Jan 11.
Leaves of Cecropia pachystachya are described in the folk medicine as possessing antitusive, expectorant, antiasthmatic and hypoglycemic effects.
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.
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.
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.
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.
在民间医学中，描述 Cecropia pachystachya 的叶子具有镇咳、祛痰、平喘和降血糖作用。
研究 Cecropia pachystachya 叶甲醇提取物的降血糖和抗氧化作用。测定了总酚和类黄酮化合物的含量，并分析了提取物的定性组成。
在正常、葡萄糖负荷和链脲佐菌素诱导的糖尿病大鼠中测试提取物的降血糖作用。通过 DPPH 自由基清除和还原能力测定评估抗氧化活性。总酚和类黄酮化合物的含量分别用 Folin-Denis 和 AlCl(3)试剂法测定。采用 HPLC-DAD 系统分析提取物的定性组成。
葡萄糖耐量试验表明，在糖尿病大鼠中，提取物在 12 小时后使血糖降低 68%，具有显著的降血糖作用。在链脲佐菌素诱导的糖尿病大鼠中给予提取物也使血糖水平在所有时间点显著降低，在 90 分钟时更为明显（降低 60%）。120 分钟后，与标准药物（二甲双胍和格列本脲）治疗的大鼠相比，提取物治疗的大鼠血糖水平无显著差异。提取物还具有相关的抗氧化活性，IC50=3.1μg/ml（DPPH 测定）和 EC50=10.8μg/ml（还原能力）。结果与参考抗氧化剂槲皮素、芦丁和抗坏血酸进行了比较。黄酮类化合物的含量为 83mg/g 植物，酚类化合物的含量为 326mg/g 植物。在提取物中鉴定出绿原酸和 C-糖苷化黄酮类化合物，即Orientin 和 Isoorientin。
总之，研究结果表明，民间药用植物 Cecropia pachystachya 具有降血糖和抗氧化作用，证实了该植物在治疗糖尿病方面的传统用途。绿原酸和 C-糖苷化黄酮类化合物可能解释了这些活性。
