Kalaivanan Kalpana, Pugalendi Kodukkur Vishwanthan
Department of Biochemistry and Biotechnology, Faculty of Science, Annamalai University, Annamalainagar - 608 002, Tamil Nadu, India.
Pharmacognosy Res. 2011 Jan;3(1):67-71. doi: 10.4103/0974-8490.79119.
Streptozotocin (STZ) selectively destroys the pancreatic insulin secreting cells, leaving less active cells and resulting in a diabetic state. The present study was designed to investigate the antihyperglycemic effect of the ethanolic seed extract of Swietenia macrophylla (SME) in normal and STZ-diabetic rats.
The experimental groups were rendered diabetic by intraperitoneal injection of a single dose of STZ (40 mg/kg body weight [BW]). Rats with glucose levels > 200 mg/dL were considered diabetic and were divided into 5 groups. Three groups of diabetic animals were orally administered, daily with seed extract at a dosage of 50, 100, and 200 mg/kg BW. One group of STZ rats was treated as diabetic control and the other group was orally administered 600 μg/kg BW glibenclamide daily.
Graded doses of seed extract and glibenclamide showed a significant reduction in blood glucose levels and improvement in serum insulin levels. The extract also improved body weight and promoted liver glycogen content. After treatment, hemoglobin (Hb) level increased and glycosylated Hb level significantly decreased in diabetic rats. The activities of the carbohydrate metabolic enzymes showed significant changes in the rats. Of the 3 doses, 100 mg dose showed maximum activity. Histological investigations of pancreas also supported the biochemical findings.
Thus, our findings indicate the folklore use of the seed for diabetes and the mechanism seems to be insulin secretion.
链脲佐菌素（STZ）可选择性破坏胰腺胰岛素分泌细胞，使活性较低的细胞留存，从而导致糖尿病状态。本研究旨在探讨大叶桃花心木种子乙醇提取物（SME）对正常大鼠和链脲佐菌素诱导的糖尿病大鼠的降血糖作用。
通过腹腔注射单剂量STZ（40mg/kg体重[BW]）使实验组大鼠患糖尿病。血糖水平>200mg/dL的大鼠被视为糖尿病大鼠，并分为5组。三组糖尿病动物每天口服剂量为50、100和200mg/kg BW的种子提取物。一组链脲佐菌素诱导的大鼠作为糖尿病对照组，另一组每天口服600μg/kg BW格列本脲。
种子提取物和格列本脲的分级剂量均显示血糖水平显著降低，血清胰岛素水平有所改善。提取物还使体重增加，并促进肝糖原含量升高。治疗后，糖尿病大鼠的血红蛋白（Hb）水平升高，糖化血红蛋白水平显著降低。碳水化合物代谢酶的活性在大鼠中显示出显著变化。在这3个剂量中，100mg剂量显示出最大活性。胰腺的组织学研究也支持了生化研究结果。
因此，我们的研究结果表明该种子在民间用于治疗糖尿病，其机制似乎是胰岛素分泌。
