桑白皮不同部位对实验性高脂糖尿病小鼠的影响

Hypoglycemic Effect of Different Effective Fractions of Cortex Mori on Experimental Diabetes Mice with Hyperlipidemia

目的建立实验性高脂糖尿病小鼠模型,分析桑白皮不同部位对其糖、脂质代谢以及股骨的影响。方法将70只雄性C57BL/6N小鼠根据体质量、血糖水平随机分为7组:即正常对照组、模型组、阳性药(二甲双胍)组、桑白皮总黄酮(MTF)组、桑白皮总生物碱(MTA)组、桑白皮总多糖(MTP)组、桑白皮药材提取物(ME)组,每组10只。高脂饲料(HFD)喂养,第7周测定小鼠血糖、血脂水平;第8周,用高脂饲料结合腹腔注射链脲佐菌素(STZ)复制糖尿病小鼠模型;第9周,测定小鼠血糖、血脂水平,第10周小鼠不禁食,乙醚麻醉,摘眼球取血后解剖取各脏器以及股骨,称质量并测定空腹血糖(FBG)、总胆固醇(TC)、甘油三酯(TG)、低密度脂蛋白(LDL-C)水平,股骨做病理切片。结果与正常对照组比较,模型组的血糖、血脂指标明显升高(P<0.01);与模型组比较,MTF组、MTA组均能明显控制高脂饲料喂养的小鼠体质量(P<0.05,P<0.01),其中MTF组能显著降低糖尿病小鼠FBG,TC,TG,LDL-C水平(P<0.05,P<0.01);MTA组能明显降低小鼠FBG、TC、TG水平(P<0.05);MTP组能明显抑制糖尿病小鼠TC、TG水平(P<0.05);MTF组和MTA组均能明显降低糖尿病小鼠尿酸(UA)和总胆红素(TBIL)水平(P<0.05)。病理切片表明正常对照组小鼠股骨未见异常;模型组小鼠股骨有不同程度的变形并且伴有骨密度的改变;MTF组小鼠6例中有3例不同程度病变。结论桑白皮各部位均具有一定的降糖作用,其中MTF对糖尿病小鼠的各项指标改善最为显著,同时对糖尿病导致的骨质疏松以及股骨头病变有抑制作用;其次是MTA,对FBG、TC、TG指标的改善作用也非常明显,MTP对指标的改善作用没有MTF和MTA显著,主要改善小鼠TG、TC水平。而ME对小鼠的各项指标均无明显影响,可能与给药剂量和提取方法有关。

Objective To establish mouse model of type 2 diabetes, and to investigate the effects of different effective parts of Cortex Mori on sugar and lipid metabolism and on the histology of the femora. Methods Seventy male C57BL/6 mice were evenly randomized into 7 groups with reference to their weight and blood glucose levels, namely normal control group, model group, metformin group, Morus total flavonoids group （MTF）, Morus total alkaloids group（MTA）, Morns total polysaccharides group（MTP）, Morns extract glucose and lipid levels of mice were detected. On week 8, group（ME）. On high-fat diet feeding week 7, blood mice were fed with high-fat forage and were given intraperitoneal injection of streptozotocin （STZ） to induce diabetes. On week 9, mice blood glucose and lipid levels were detected again. On week 10, blood sampling from the eyeballs, organ removal and the femora sampling were performed after etherization. And then we tested the levels of fasting blood glucose（FBG）, triglyceride（TG）, total cholesterol（TC） and low density lipoprotein-cholesterol（LDL-C）, and prepared femoral pathological section. Results Compared to the normal control group, the blood glucose and lipid levels of the model group were significantly elevated （P 〈 0.01 ）. In comparison with the model group, mice weight fed with high-fat forage was much controled in MTF and MTA groups （P 〈 0.05, P 〈 0.01 ）, and MTF had obvious effect on decreasing the levels of FBG, TG, TC and LDL-C（P 〈 0.05, P 〈 0.01）, MTA remarkably lowered FBG, TC and TG levls （P 〈 0.05）, and MTP distinctly decreased TC and TG levels （P 〈 0.05）. The uric acid and total bilirubin levels of MTF and MTA groups were lower than those of the model group（P 〈 0.05 ）. The pathological section of femoral showed that the normal control group had no pathological changes, while the model group had various degrees of deformation, and were accompanied by changes in bone mineral density. Three cases of MTF group had various degrees of pathological changes. Conclusion Hypoglycemic effect of different effective parts of Cortex Mori has been shown in this study. MTF has the most obvious effect on improving the indexes of diabetic mice and has inhibitory effect on diabetic osteoporosis and bone lesions. MTA comes next, and it also has markedly effects on improving FBG, TC and TG. The effect of MTP is inferior to that of MTF and MTA, and it can also improve mice TG and TC levels. ME has no effect on the the observation indexes, which is probably due to the medication dose and extraction method.