Singh S N, Vats P, Suri S, Shyam R, Kumria M M, Ranganathan S, Sridharan K
Defence Institute of Physiology and Allied Sciences, Lucknow Road, Timarpur, Delhi 110054, India.
J Ethnopharmacol. 2001 Aug;76(3):269-77. doi: 10.1016/s0378-8741(01)00254-9.
Hypoglycemic activity was detected in dichloromethane:methanol extract (1:1) of leaves and twigs of Catharanthus roseus (family Apocynaceae), a traditionally used medicinal plant, using streptozotocin (STZ) induced diabetic rat model. Extract at dose 500 mg/kg given orally for 7 and 15 days showed 48.6 and 57.6% hypoglycemic activity, respectively. Prior treatment at the same dose for 30 days provided complete protection against STZ challenge (75 mg/kg/i.p.x1). Enzymic activities of glycogen synthase, glucose 6-phosphate-dehydrogenase, succinate dehydrogenase and malate dehydrogenase were decreased in liver of diabetic animals in comparison to normal and were significantly improved after treatment with extract at dose 500 mg/kg p.o. for 7 days. Results indicate increased metabolization of glucose in treated rats. Increased levels of lipid peroxidation measured as 2-thiobarbituric acid reactive substances (TBARS) indicative of oxidative stress in diabetic rats were also normalized by treatment with the extract.
长春花（夹竹桃科）是一种传统药用植物，利用链脲佐菌素（STZ）诱导的糖尿病大鼠模型，在其叶和嫩枝的二氯甲烷：甲醇提取物（1:1）中检测到了降血糖活性。以500mg/kg的剂量口服给药7天和15天的提取物分别显示出48.6%和57.6%的降血糖活性。以相同剂量预先处理30天可提供完全保护，使其免受STZ攻击（75mg/kg/腹腔注射×1）。与正常动物相比，糖尿病动物肝脏中的糖原合酶、葡萄糖6-磷酸脱氢酶、琥珀酸脱氢酶和苹果酸脱氢酶的酶活性降低，在用500mg/kg口服剂量的提取物处理7天后显著改善。结果表明，处理后的大鼠葡萄糖代谢增加。以2-硫代巴比妥酸反应性物质（TBARS）衡量的糖尿病大鼠氧化应激指标脂质过氧化水平的升高，也通过提取物处理恢复正常。
