Division of Ethnopharmacology, Entomology Research Institute, Loyola College, Chennai 600 034, India.
J Ethnopharmacol. 2011 Mar 24;134(2):298-304. doi: 10.1016/j.jep.2010.12.018. Epub 2010 Dec 21.
Symplocos cochinchinensis (Lour.) S. Moore. is used in Indian system of traditional medicine to treat diabetes mellitus. The present study aims to investigate the antidiabetic efficacy of the hexane extract of Symplocos cochinchinensis leaves in high fat diet-low streptozotocin (STZ) induced type 2 diabetic rats.
The doses for the study were fixed based on Irwin test. The hypoglycemic effect of the hexane extract of Symplocos cochinchinensis leaves were studied in normal rats. Oral glucose and insulin tolerance tests were carried out. The antihyperglycemic effect of the hexane extract at 250 and 500 mg/kg was studied in high fat diet-low STZ induced type 2 diabetic rats for 28 days.
The extracts showed no adverse effects up to 5 g/kg concentration. In hypoglycemic study, after treatment with hexane extract at 250 and 500 mg/kg the blood glucose was mildly reduced. In oral glucose tolerance test, the treatment with the hexane extract at 250 and 500 mg/kg showed a highly significant reduction of 12.07% and 23.58% in plasma glucose levels, respectively 30 min after glucose load. The insulin tolerance test also showed improved insulin sensitivity after 60 min of insulin treatment. In high fat diet-low STZ induced type 2 diabetic rats, after 28 days treatment with the hexane extract at 250 and 500 mg/kg reduced the plasma glucose level by 17.04% and 42.10%, respectively. A significant reduction in plasma insulin, plasma and hepatic total cholesterol (TC), triglycerides (TG) and free fatty acids (FFA) and a significant increase in liver glycogen were observed in treated diabetic rats.
This study demonstrated the potential antidiabetic property of hexane extract of Symplocos cochinchinensis leaves on type 2 diabetes mellitus, thus justifying its traditional usage.
琼楠（Symplocos cochinchinensis（Lour.）S. Moore.）被用于印度传统医学体系来治疗糖尿病。本研究旨在探究琼楠叶己烷提取物在高脂肪饮食-低链脲佐菌素（STZ）诱导的 2 型糖尿病大鼠模型中的降血糖作用。
根据 Irwin 试验确定研究剂量。研究了琼楠叶己烷提取物对正常大鼠的降血糖作用，进行了口服葡萄糖和胰岛素耐量试验。研究了己烷提取物在 250 和 500 mg/kg 剂量下对 28 天高脂肪饮食-低 STZ 诱导的 2 型糖尿病大鼠的抗高血糖作用。
提取物在高达 5 g/kg 浓度下无不良反应。在降血糖研究中，用 250 和 500 mg/kg 的己烷提取物治疗后，血糖略有降低。在口服葡萄糖耐量试验中，己烷提取物 250 和 500 mg/kg 剂量组在葡萄糖负荷后 30 分钟时，血糖水平分别显著降低 12.07%和 23.58%。胰岛素耐量试验也表明，在胰岛素治疗 60 分钟后，胰岛素敏感性得到改善。在高脂肪饮食-低 STZ 诱导的 2 型糖尿病大鼠中，用 250 和 500 mg/kg 的己烷提取物治疗 28 天后，分别降低了 17.04%和 42.10%的血浆葡萄糖水平。在治疗糖尿病大鼠中，观察到血浆胰岛素、血浆和肝总胆固醇（TC）、甘油三酯（TG）和游离脂肪酸（FFA）显著降低，肝糖原显著增加。
本研究证明了琼楠叶己烷提取物对 2 型糖尿病具有潜在的降血糖作用，证实了其传统用途。
