扁桃斑鸠菊及非洲印楝叶的提取物对链脲佐菌素致糖尿病大鼠肝脏形态学及肝毒性标志物的影响(英文)

Effects of combined leaf extract of Vernonia amygdalina and Azadirachta indica on hepatic morphology and hepatotoxicity markers in streptozotocin-induced diabetic rats

目的:研究扁桃斑鸠菊及非洲印楝叶的提取物对链脲佐菌素致糖尿病大鼠肝脏形态学、肝脏氧化性应激标志物及部分肝脏酶类的影响。方法:大鼠腹腔注射链脲佐菌素致糖尿病。不同治疗组大鼠分别口服扁桃斑鸠菊及非洲印楝叶的提取物(500mg/kg)或二甲双胍(150mg/kg),疗程8周,每周测量大鼠的血糖水平及体质量变化。8周后麻醉处死大鼠。取肝组织制成切片,希夫染色法染色,并测量肝匀浆中丙二醛和谷胱甘肽过氧化物酶的含量;下腔静脉采血,分离血浆,检测血浆中丙氨酸氨基转移酶和天冬氨酸氨基转移酶的活性。结果:二甲双胍及植物提取物均能显著改善糖尿病大鼠的血糖水平,且与糖尿病模型组相比,治疗组的体质量明显增加(P<0.05)。光学显微镜下,各组大鼠的肝脏形态学无明显差别。植物提取物治疗组大鼠的血浆丙氨酸氨基转移酶及天冬氨酸氨基转移酶的活性与正常对照组相比无明显变化(P>0.05),而丙二醛含量明显下降(P<0.05)。结论:扁桃斑鸠菊及非洲印楝叶的提取物对糖尿病大鼠有明显的降糖作用,而肝脏形态学及肝毒性标志物没有明显变化。

Objectives： In this work, we studied liver morphology, markers of hepatic oxidative stress and some liver enzymes in diabetic rats treated with the combined leaf extract （CLE） of Vernonia amygdalina （bitter leaf） and Azadirachta indica （neem）.Methods： Diabetes was induced in fasted male Wistar rats with intraperitoneal injection of streptozotocin （STZ）. Oral CLE （500 mg/kg body weight） and metformin （150 mg/kg body weight） were administered to different groups of diabetic rats for eight weeks. Blood glucose and change in body weight were estimated weekly. All animals were sacrificed under anaesthesia after eight weeks. Hepatic sections were stained with periodic acid-Schiff. Liver samples were homogenized and assayed for contents of malondialdehyde （MDA） and glutathione peroxidase （GPx）, while the plasma was assayed for contents of alanine aminotransferase （ALT） and aspartate aminotransferase （AST）.Results： Mettormin and GLE treatment produced normoglycaemia in the diabetic ratsi n the course of the treatment period. Significant increases in body weight were observed in the treatment groups compared with the diabetic control rats （P〈0. 05）. In the control and treatment groups, light microscopic study showed intact hepatic histology. Plasma ALT and AST were not significantly different from the control values in the CLE-treated rats. In addition, from week four onwards, blood glucose concentrations in the CLE-treated rats were not different from the normal control （P〈0, 05）. Besides, hepatic MDA （P〈0. 05） significantly decreased in the CLE-treated rats compared with the normal control. Conclusion： These findings suggest that CLE ameliorates hyperglycemia and hepatic oxidative stress when administered to diabetic rats as a chronic regimen, and there was no morphologic or biochemical evidence of liver damage at the dose tested.