龙眼核原花青素提取物对Ⅱ型糖尿病小鼠血糖血脂的影响

Effect of longan seed proanthocyanidin extract on the blood glucose and blood lipid of type Ⅱ diabetic mice

目的研究龙眼核原花青素提取物(longan seed proanthocyanidin extract,LSPE)对链脲佐菌素(streptozotocin,STZ)所致糖尿病小鼠血糖血脂的影响,并探讨相关作用机制。方法通过高脂饲喂结合腹腔注射STZ造糖尿病小鼠模型,将造模成功的糖尿病小鼠随机分为模型组、二甲双胍组(250 mg·kg^(-1)),LSPE高剂量组(300 mg·kg^(-1))、中剂量组(150 mg·kg^(-1))、低剂量组(75 mg·kg^(-1)),连续灌胃8周后通过断尾取血测定糖尿病小鼠空腹血糖;摘眼球取血,分离血清,测定血清中甘油三脂(triglyceride,TG)、总胆固醇(total cholesterol,TC)、高密度脂蛋白胆固醇(high density lipoprotein cholesterol,HDL-C)和低密度脂蛋白胆固醇(low density lipoprotein cholesterol,LDL-C)的含量;采用试剂盒测定血清白细胞介素6(interleukin-6,IL-6)含量、C反应蛋白(C reactive protein,CRP)含量、超氧化物歧化酶(superoxide dismutase,SOD)活性、胰岛素(insulin,INS)含量及丙二醛(malondialdehyde,MDA)含量;分离胰腺,HE染色观察胰腺组织学改变。结果与模型组比较,LSPE能改善糖尿病小鼠一般情况,缓解糖尿病小鼠体重减轻的症状;LSPE各组糖尿病小鼠的血糖下降;与模型组比较,LSPE高、中剂量组能显著增加INS含量,降低血浆中TG、IL-6和CRP含量,增加SOD活性(P<0.05);高剂量组能显著降低血清TC和MDA含量,增加HDL-C水平(P<0.05);糖尿病小鼠胰腺病变组织得到修复。结论龙眼核原花青素提取物对STZ所导致的糖尿病小鼠有明显的降低血糖和改善血脂,修复胰脏病变组织的作用,其作用机制可能与其能提高糖尿病小鼠机体抗氧化能力、降低炎症因子含量有关。

Objective To study the effects of longan seed proanthocyanidin extract（ LSPE） on blood glucose and blood lipid of diabetic mice,and to explore the relevant mechanism. Methods Diabetic mice model was made by feeding of high fat diet combined with intraperitoneal injection of STZ and then diabetic mice were randomly divided into model group,metformin group（ 250 mg ·kg^（-1））,LSPE high-dose group（ 300 mg·kg^（-1））,LSPE middle-dose group（ 150 mg·kg^（-1）） and LSPE low-dose group（ 75 mg·kg^（-1））.Fasting blood glucose was measured after continuous intragastric administration of LSPE for 8 weeks. Blood samples were taken out from the tail of diabetic mice for fasting blood glucose measurement. The concentration of triglyceride（ TG）, total cholesterol（ TC）,high density lipoprotein cholesterol（ HDL-C） and low density lipoprotein cholesterol（ LDL-C）,serum IL-6,CRP,SOD, INS and MDA in serum separated from the blood samples withdrawn from the eyeball were analyzed separately. Pathological changes of pancreas were observed with HE staining. Results LSPE can improve the general situation of diabetic mice and alleviate the symptoms of diabetes weight loss. In all LSPE administered groups, the blood glucose level in STZ induced diabetic mice was significantly lower than control group. In LSPE high and middle-dose group, INS content and SOD activity were higher than that of the control group significantly（ P 0. 05）,while the content of TG、IL-6 and CRP was lower than that of the control group significantly. TC and MDA content in LSPE high-dose group was lower than that of the control group significantly（ P 0. 05）. HDL-C content in LSPE high-dose group was higher than that of the control group significantly（ P 0. 05）. Damage to pancreatic tissue of diabetic mice were repaired. Conclusions The longan seed proanthocyanidin extract had a significant effect of reducing blood glucose, improving blood lipid level,and repairing pancreatic tissue. The mechanism might be related to the improvement of the antioxidant capacity and reduction of the content of inflammatory factors in diabetic mice by LSPE.