沙棘籽渣黄酮和沙棘油对高糖高脂诱导的老年肥胖雌鼠血脂的影响

目的:观察沙棘籽渣黄酮和沙棘油对老年肥胖雌鼠血脂的影响。方法:应用沙棘籽渣黄酮和沙棘油对高糖高脂诱导的老年肥胖雌鼠进行灌胃给药,连续6w,观察对老年肥胖雌鼠体重、肥胖指数、血脂及游离脂肪酸、高低密度脂蛋白等指标的影响。结果:沙棘籽渣黄酮可显著降低老年肥胖雌鼠的肥胖指数,有效控制其体重增加;并能极显著降低模型动物血清甘油三酯和游离脂肪酸水平;沙棘油可显著降低老年肥胖雌鼠的游离脂肪酸水平。结论:沙棘籽渣黄酮和沙棘油均可显著改善老年肥胖雌鼠血脂状况。     

沙棘籽油对大鼠溃疡性结肠炎组织的保护作用及其机制

目的研究沙棘籽油对葡聚糖硫酸钠(dextran sulfate sodium,DSS)诱导的大鼠溃疡性结肠炎组织损伤的保护作用,并初步探讨其作用机制。方法应用DSS制备大鼠溃疡性结肠炎模型。24只雄性大鼠随机分为正常对照组,DSS模型组和沙棘籽油干预3组。从造模开始,沙棘籽油干预组用沙棘籽油连续灌胃,其余两组等量蒸馏水灌胃。4w后处死所有大鼠,观察大鼠结肠组织大体形态,并进行组织学评分。生化法检测大鼠血清和结肠组织髓过氧化物酶(myeloperoxidase,MPO)、超氧化物歧化酶(superoxide dismutase,SOD)和谷胱苷肽过氧化物酶(glutathione peroxidase,GSH-Px)活性及丙二醛(malondialdehyde,MDA)含量。结果与DSS模型组相比,沙棘籽油组结肠MPO活性,降低血清和结肠MDA含量明显降低,血清和结肠SOD、GSH-Px活性升高,大鼠溃疡性结肠炎大体形态明显改善和组织学评分降低。结论沙棘籽油对DSS诱导大鼠溃疡性结肠炎有明显保护作用,抗氧化损伤可能是其作用机制。[营养学报,2012,34(4):349-352]     

阿卡波糖调节2型糖尿病大鼠肠道SGLT1表达的影响

目的探讨2型糖尿病大鼠模型的建模方法,对比阿卡波糖(拜唐苹)与格列美脲调节2型糖尿病大鼠的血糖水平,探讨阿卡波糖对2型糖尿病大鼠肠道钠-葡萄糖协同转运蛋白1(SGLT1)表达的影响。方法将40只SD雄性大鼠随机分为5组:正常对照组、正常对照+拜唐苹干预组、2型糖尿病模型对照组、糖尿病模型+拜唐苹干预组和糖尿病模型+格列美脲干预组,每组8只。糖尿病组的大鼠均给予高脂乳剂灌胃和高糖饮水,连续灌胃4周后,模型组大鼠一次性腹腔注射小剂量链脲佐菌素(STZ)以建立2型糖尿病大鼠模型。建模成功后,连续药物干预4周,观察大鼠血糖水平变化,运用反转录定量PCR(q RT-PCR)和免疫组化技术分别检测大鼠肠道组织SGLT1基因和蛋白的表达水平。结果与正常对照组比较,2型糖尿病模型对照组大鼠血糖明显升高78%,并显著上调肠道组织中SGLT1基因和蛋白的表达(P0.05)。给药4周后,与模型对照组比较,拜唐苹干预组和格列美脲干预组明显降低糖尿病大鼠的血糖,拜唐苹干预组降低46%,格列美脲干预组降低24%,拜唐苹干预组和格列美脲干预组能够下调2型糖尿病大鼠肠道组织中SGLT1基因和蛋白的表达(P0.05),在相同血糖水平下,拜唐苹干预组效果更显著。结论对SD大鼠给予高脂乳剂灌胃联合一次性小剂量STZ注射可以成功诱导2型糖尿病模型。拜唐苹和格列美脲对2型糖尿病大鼠有降低血糖的治疗作用,并且对糖尿病大鼠肠道SGLT1受体的表达有一定的影响。在相同血糖水平下,比较格列美脲和拜唐苹的干预效果显示,拜唐苹对2型糖尿病大鼠肠道SGLT1表达的影响更显著。     

补充锌和/或维生素E对糖尿病大鼠血一氧化氮和内皮素的影响

目的 :　探讨锌和 /或维生素 E(VE)减轻糖尿病 (DM)大鼠氧化应激及对内皮细胞的保护作用。方法 :　对 STZ诱导的糖尿病大鼠模型 ,补充锌和 /或 VE,6 w后观察血糖、血清胰岛素、血清总抗氧化能力 (T- AOC)、血清丙二醛 (MDA)、血一氧化氮 (NO)和内皮素 (ET)、主动脉一氧化氮合成酶 (NOS)活性的变化。结果 :　锌和 /或 VE可以降低血糖、MDA、NO和 ET水平 ,提高血清胰岛素水平、总抗氧化能力。结论 :　补充锌和 /或维生素 E可以减轻糖尿病大鼠氧化应激 ,保护内皮细胞 ,影响血 NO和 ET水平     

生命早期经饲料补充维生素D对链脲菌素致小鼠糖尿病的影响

目的探讨生命早期经饲料补充维生素D对链脲菌素作用小鼠空腹血糖和胰岛素水平,糖尿病发病率,以及链脲菌素致胰岛损伤的影响。方法 C57BL/6鼠离乳后分别饲喂标准饲料和补充维生素D(VD)饲料9周后注射链脲菌素(STZ),继续喂养4周,注射STZ后每周末测定空腹血糖,计算糖尿病发病率,4周后测血清胰岛素水平,并采用HE染色法观察胰腺形态学变化。结果①生命早期补充VD能降低STZ作用小鼠的空腹血糖水平,并以补充高剂量VD的降糖效果最好,其在注射STZ后4周血糖值明显低于糖尿病模型组(P<0.01);②生命早期补充VD降低STZ致小鼠糖尿病发病率,并以补充高剂量VD的干预效果最好,其在注射STZ后4周时糖尿病发病率为0%,完全抑制糖尿病的发病(P<0.01);③生命早期补充高剂量和中剂量VD明显上调STZ作用小鼠的血清胰岛素水平(P<0.05),并以补充高剂量VD的上调作用最显著(P<0.01)。④生命早期补充高剂量和中剂量VD对STZ致胰岛损伤有明显保护作用,且以补充高剂量VD的保护作用最好。结论生命早期补充一定量VD能降低STZ作用小鼠的血糖水平和糖尿病发病率,上调血清胰岛素水平,改善STZ对胰岛细胞的损伤,且均以补充高剂量VD的作用最显著。     

仙鹤草对糖尿病大鼠血糖胰岛素水平的影响

目的观察仙鹤草对糖尿病大鼠血糖、胰岛素水平影响的动态变化,为抗糖尿病药物的开发提供依据。方法选择雄性SD大鼠,腹腔注射链脲佐菌素(streptozotocin,STZ)建立糖尿病大鼠动物模型。将造模成功的糖尿病大鼠随机分为糖尿病模型组,仙鹤草低剂量组(60 g/kg)、仙鹤草高剂量组(120 g/kg),每天经口灌胃,连续4周,另设正常对照组。观察仙鹤草对糖尿病大鼠体重、血糖及血清胰岛素水平的影响的动态变化,实验结束后取胰腺用10%甲醛溶液固定,做病理组织学检查。结果实验结束时,糖尿病模型组大鼠血糖、胰岛素水平分别为(17.55±6.08)mmol/L和(7.53±2.15)μU/ml,仙鹤草低、高剂量组胰岛素水平分别为(16.79±6.81)μU/ml和(18.29±7.15)μU/ml,显著高于糖尿病纽(P0.01);血糖水平分别为(4.71±2.19)mmol/L和(3.92±1.17)mmol/L,显著低于糖尿病组(P0.01)。结论仙鹤草可通过增加胰岛素分泌发挥降糖作用。     

三种食物多酚对化学诱导DM大鼠糖脂代谢的影响

目的探讨膳食多酚[绿原酸、表没食子儿茶素没食子酸酯(EGCG)、槲皮素]对链脲佐菌素(STZ)诱导的糖尿病大鼠血糖、血脂、肝脏中葡萄糖-6-磷酸酶(G-6-pase)和骨胳肌组织中葡萄糖转运体4(GLUT4)表达的影响。方法单次腹腔注射链脲佐菌素(STZ,35 mg/kg)结合高脂饮食建立糖尿病大鼠模型,将成模大鼠分成5组[糖尿病模型组(DM)、糖尿病模型+二甲双胍组(S)、糖尿病模型+绿原酸组(CA)、糖尿病模型+EGCG组(E)、糖尿病模型+槲皮素组(Q)],另设正常对照组(NC),分别灌喂二甲双胍、绿原酸、EGCG和槲皮素4w后,测定其糖耐量、空腹胰岛素、甘油三酯、胆固醇、G-6-pase和GLUT4 mRNA的表达。结果绿原酸、EGCG、槲皮素均表现出改善STZ诱导的糖尿病大鼠血糖、甘油三酯(TG)和胆固醇(TC)的含量,并能改善糖尿病模型大鼠的胰岛素敏感性,抑制肝脏G-6-pase mRNA的表达,且提高了骨胳肌GLUT4 mRNA的表达,其中以绿原酸效果最佳。仅仅其糖耐量改善弱于槲皮素作用,但均弱于阳性对照组二甲双胍的作用。结论绿原酸、EGCG、槲皮素均能有效改善STZ诱导的SD糖尿病大鼠的糖代射、脂代射、胰岛素敏感生及肝脏G-6-pase mRNA和骨胳肌GLUT4 mRNA的表达,绿原酸的效果最佳。[营养学报,2012,34(6):572-575,581]     

沙棘籽油对四氯化碳肝损伤的保护作用研究

目的研究沙棘籽油对四氯化碳(CCl4)引起的大鼠化学性肝损伤的保护作用,探讨其对CCl4肝损伤起保护作用的有效剂量。方法实验用健康雄性成年SD大鼠(180~220 g)72只,随机分为空白对照组、溶剂对照组、CCl4模型对照组和3个沙棘籽油实验组(0.167,0.333和0.500 g/kg体重)。沙棘籽油以食用花生油稀释至所需浓度,灌胃给予动物(2 ml/kg体重),空白对照组给予等体积蒸馏水灌胃,溶剂和模型对照组给予等体积花生油灌胃。于实验第45天将各组动物隔夜禁食16 h,模型组及受试样品组一次灌胃给予CCl4(200 mg/kg体重),24 h后处死动物,股动脉取血分离血清,测定血清ALT、AST水平,并取肝脏进行病理组织学检测。结果与CCl4模型对照组相比,沙棘籽油各剂量组大鼠血清ALT、AST均明显降低[(2 419±1 335),(2 832±1 074),(2 424±955),(4 396±3 026),(4 579±990),(5 106±1 479),(4 503±782),(21 861±14 291)nmol.s-1/L](P0.05);病理组织学检查结果显示,沙棘籽油高剂量组(0.500 g/kg体重)大鼠肝细胞水样变性和坏死程度以及总病变计分明显减轻(136.0±47.0vs288.0±70.0,P0.05),而中、低剂量组差异无统计学意义。结论沙棘籽油对CCl4造成的肝损伤具有明显保护作用,本实验中得出的有效剂量为0.500 g/kg体重。     

锌和维生素E对糖尿病大鼠内皮细胞保护作用

目的探讨锌(Zn)和维生素E(VE)对链脲佐菌素(STZ)诱导的糖尿病(DM)大鼠氧化应激及内皮细胞的保护作用。方法对STZ诱导的糖尿病大鼠模型，补充Zn和VE，6周后观察血糖、血清胰岛索、血清总抗氧化能力(T—AOC)、血清丙二醛(MDA)、血浆血栓素B2(TXB2)、6-酮-前列腺素F1α(6-k-PGF1α)和内皮素(ET)变化。结果Zn和VE可以降低血糖、MDA、TXB2和ET水平，同时提高血清胰岛素水平、T—AOC和血浆6-k—PGF1α水平。结论补充Zn和VE可以减轻糖尿病大鼠氧化应激，保护内皮细胞，影响血浆TXB2、6-k—PGF1α和ET水平。     

蝇蛆粉、南瓜粉、茶叶粉及魔芋精粉混合物对2型糖尿病大鼠免疫功能影响的研究

[目的]探讨蝇蛆、茶叶、魔芋精粉、南瓜粉混合物对2型糖尿病大鼠免疫功能的影响. [方法]选择健康Wistar大鼠60只.将大鼠按随机数字表法分成2组:正常对照组16只,糖尿病造模组44只.糖尿病造模组大鼠以高脂高糖饲料诱导4周加小剂量链脲佐菌素(STZ)腹腔注射(30 mg/kg)进行造模,空腹血糖≥16.7 mmol/L为造模成功.将造模成功的糖尿病大鼠39只按随机数字表法分为2组:模型对照组(19只)和模型实验组(20只).正常对照组和模型对照组饲以基础饲料:模型实验组饲以混合饲料.动物继续喂养8周后摘眼球取血,用全自动生化分析仪测定血糖、总蛋白(TP)、白蛋白(A|b)、免疫球蛋白IgG、IgM、补体C3、C4;用全自动血细胞分析仪测定白细胞、淋巴细胞;用全自动流式细胞仪测定CD3+,CD4+,CD8+.取动物的胸腺和脾脏组织,用分析天平称量并计算出脏器指数.[结果] (1)注射STZ前,各组之间的血糖水平差异无统计学意义(P>0.05).注射STZ 1周后,糖尿病造模组的平均血糖值为(24.40±5.15)mmol/L,高于正常对照组,差异有统计学意义(P<0.05).大鼠继续喂养8周后,模型对照组和模型实验组的血搪值高于正常对照组.差异有统计学意义(P<0.05);模型实验组的血糖值低干模型对照组,差异有统计学意义(P<0.05). (2)模型对照组和模型实验组的总蛋白水平、IgG、C4、CD4+、胸腺指数均低于正常对照组,差异有统计学意义(P<0.05);模型对照组的白蛋白水平、IgM、淋巴细胞百分比、CD3+、CD4+/CD8+、脾指数均低于正常对照组,差异有统计学意义(P<0.05);模型实验组的总蛋白、白蛋白、IgG、IgM、淋巴细胞百分比、CD3+、CD4+、脾指数、胸腺指数均高于模型对照组,差异有统计学意义(P<0.05).[结论] (1)混合物对糖尿病大鼠有一定的降糖作用. (2)混合物可适当升高糖尿病大鼠的免疫水平. (3)蝇蛆、茶叶、魔芋精粉、南瓜粉混合物或许是2型糖尿病病人比较理想的增强免疫力的辅助食物.     

Antihyperglycemic property of Tragia cannabina in streptozotocin-induced diabetic rats

The present study was performed to investigate the efficacy of an ethanol extract of the roots of Tragia cannabina for antihyperglycemic and antioxidant effects in streptozotocin (STZ)-induced diabetic rats. Male Wistar rats were administered T. cannabina (250 mg/kg) orally for 21 days, and blood glucose level was measured weekly. At the end of 21 days, concentrations of serum lipids such as total cholesterol, triglycerides, and high-density lipoprotein (HDL) and protein markers such as total protein, albumin, globulin, and albumin:globulin ratio (A:G) were estimated. Also, levels of enzymes such as serum glutamate oxaloacetate transaminase (SGOT), serum glutamate pyruvate transaminase (SGPT), and alkaline phosphatase (ALP) were determined. Antioxidant activity of the extract was evaluated by estimating lipid peroxides (LPO), superoxide dismutase (SOD), and catalase in liver of normal control and STZ- and extract-treated rats. Histopathological changes of liver and kidney were also studied in STZ-induced diabetic animals and normal controls. All these effects produced by the extract were compared with glibenclamide, a standard antidiabetic drug. Oral administration of T. cannabina for 21 days resulted in a significant reduction in blood glucose level, lipid concentration, and SGOT, SGPT, ALP, and LPO levels accompanied by an increase in the levels of SOD and catalase in liver tissues of STZ-induced diabetic rats. Altered levels of protein markers also reverted back to normal. Histopathological changes of liver and kidney were returned to normal. The effects produced by the extract were comparable to that of glibenclamide. In conclusion, the T. cannabina showed significant antihyperglycemic and antioxidant effects in STZ-induced diabetic rats.     

Antihyperglycemic effect of Fomitopsis pinicola extracts in streptozotocin-induced diabetic rats

The antihyperglycemic effect of a water extract (WE) and an alkali extract (AE) of the Fomitopsis pinicola fruit body was studied in streptozotocin (STZ)-induced diabetic rats. The STZ-induced diabetes mellitus (DM) control group lost a significant amount of body weight, whereas the normal control group (NC) gained weight; however, the DM-AE group gained a significant amount of weight, with weight gain approaching normal. Feed intake by the DM-AE group was also similar to the NC group. The liver and kidney weights per body weight increased with the STZ treatment; however, the weights were lower in the F. pinicola-treated groups and nearly normalized in the DM-AE group. The weights of the heart, lungs, and spleen were not influenced by the STZ treatment. Blood glucose levels of F. pinicola-treated DM groups were significantly lower than that of the DM group. In particular, STZ-induced hyperglycemia was remarkably inhibited by the AE-supplemented diet. Serum insulin levels were decreased with STZ injection; however, the decreased levels were almost restored to the NC level with F. pinicola supplementation. The increased serum fructosamine levels associated with hyperglycemia were decreased with the F. pinicola treatment. Cells of the pericentral regions were found to have significant swelling, and some necrotic cells were observed in the pancreas of DM animals; however, pancreatic tissue damage by STZ in the F. pinicola-supplemented diet groups was ameliorated. In this study, the AE from F. pinicola showed the highest antidiabetic effect among the treatments. These results indicate that constituents of F. pinicola may regulate hyperglycemia via either increased insulin secretion during recovery or the prevention of STZ-induced pancreatic damage. This is the first report of antihyperglycemic effects of F. pinicola in STZ-induced DM rats.     

苦瓜多糖对链脲佐菌素诱导糖尿病小鼠的降血糖效果

目的:研究苦瓜水提多糖(watersolublepolysaccharidesofMomordicacharantiaL.MCW)和苦瓜碱提多糖(alkalinesolublepolysaccharidesofMomordicacharantiaL.MCB)对STZ诱导糖尿病小鼠的降血糖作用。方法:昆明种小鼠120只,随机抽取12只作空白对照,余下108只,禁食后于次日晨腹腔注射链脲佐菌素(STZ)200mg/kgbw。取血糖值在11.1mmol/L以上者随机分组,共4组:模型组、MCW组(300mg/kgbw)、MCB组(300mg/kgbw)和优降糖组(15mg/kgbw)。连续灌胃10d后,禁食,次日晨眼眶取血,测定血糖及血清胰岛素含量。解剖取胰腺,观察小鼠胰岛组织形态。结果:MCW和MCB都可以降低糖尿病小鼠空腹血糖,MCB组分的降血糖效果最佳,不但可以显著降低糖尿病小鼠空腹血糖值,而且可以提高糖尿病小鼠血清胰岛素水平。结论:苦瓜多糖能帮助恢复受损胰岛组织,促进胰岛素的分泌,从而降低血糖。     

Supplementation of fenugreek leaves lower lipid profile in streptozotocin-induced diabetic rats

The present study was undertaken to evaluate the lipid-lowering effect of fenugreek leaves in diabetes mellitus. Albino Wistar rats were randomly divided into six groups: normal untreated rats; streptozotocin (STZ)-induced diabetic rats; STZ-induced rats + fenugreek leaves (0.5 g/kg of body weight); STZ-induced rats + fenugreek leaves (1 g/kg of body weight); STZ-induced rats + glibenclamide (600 microg/kg of body weight); and STZ-induced rats + insulin (6 units/kg of body weight). Rats were made diabetic by STZ (40 mg/kg) injected intraperitoneally. Fenugreek leaves were supplemented in the diet daily to diabetic rats for 45 days, and food intake was recorded daily. Blood glucose, total cholesterol, triglycerides, and free fatty acids were determined in serum, liver, heart, and kidney. Our results show that blood glucose and serum and tissue lipids were elevated in STZ-induced diabetic rats. Supplementation of fenugreek leaves lowered the lipid profile in STZ-induced diabetic rats.     

Hypoglycemic effect of Lentinus strigosus (Schwein.) Fr. crude exopolysaccharide in streptozotocin-induced diabetic rats

ABSTRACT This study reports the hypoglycemic effects of the crude exopolysaccharide (EPS) produced from submerged mycelial culture of Lentinus strigosus (Schwein.) Fr. (Family Polyporaceae) in streptozotocin (STZ)-induced diabetic rats. In a dose-dependent study, diabetic rats were treated with EPS at doses of 50-150 mg/kg of body weight for 7 days. Serum glucose and plasma insulin levels were measured in normal, STZ-induced diabetic, and EPS-treated diabetic rats. Following oral administration of EPS dosages for 7 days, the serum glucose levels in the STZ-induced diabetic rats were reduced up to 21.1% at the dose of 150 mg/kg of body weight. The results revealed that orally administered L. strigosus EPS, at the dose of 150 mg/kg, exhibited a considerable hypoglycemic effect in STZ-induced diabetic rats. Plasma insulin levels of STZ-induced diabetic rats decreased as compared to control group rats (P < .05). Although insulin levels slightly increased in the EPS-treated groups the increase was not statistically significant. The hypoglycemic potential of the EPS was further supported by histological observations of pancreatic islets of Langerhans.     

Alterations in the blood glucose, serum lipids and renal oxidative stress in diabetic rats by supplementation of onion (Allium cepa. Linn)

This study examined the anti-diabetic effect of onion (Allium cepa. Linn) in the streptozotocin (STZ)-induced diabetic rats. Male Sprague-Dawley rats were divided into normal rats fed control diet or supplemented with onion powder (7% w/w) and diabetic rats fed control diet or supplemented with onion powder. Diabetes was induced by a single injection of STZ (60 mg/kg, ip) in citrate buffer. The animals were fed each of the experimental diet for 5 weeks. Blood glucose levels of rats supplemented with onion were lower than those of rats fed control diet in the diabetic rats. Onion also decreased the total serum lipid, triglyceride, and atherogenic index and increased HDL-cholesterol/total cholesterol ratio in the diabetic rats. Glutathione peroxidase, glutathione reductase and glutathione S-transferase activities were high in the diabetic rats compared to normal rats and reverted to near-control values by onion. These results indicate that onion decreased blood glucose, serum lipid levels and reduced renal oxidative stress in STZ-induced diabetic rats and this effect might exert the anti-diabetic effect of onion.     

Anti-diabetic and hypolipidaemic properties of ginger (Zingiber officinale) in streptozotocin-induced diabetic rats

In the present study, the hypoglycaemic potentials of ginger (Zingiber officinale) were studied in rats. An aqueous extract of raw ginger was administered daily (500 mg/kg, intraperitoneally) for a period of 7 weeks to streptozotocin (STZ)-induced diabetic rats. Fasting blood serum was analysed for blood glucose, cholesterol and triacylglycerol levels. The STZ-injected rats exhibited hyperglycaemia accompanied with weight loss, indicating their diabetic condition. At a dose of 500 mg/kg, raw ginger was significantly effective in lowering serum glucose, cholesterol and triacylglycerol levels in the ginger-treated diabetic rats compared with the control diabetic rats. The ginger treatment also resulted in a significant reduction in urine protein levels. In addition, the ginger-treated diabetic rats sustained their initial weights during the treatment period. Moreover, ginger decreased both water intake and urine output in the STZ-induced diabetic rats. The present results indicate that raw ginger possesses hypoglycaemic, hypocholesterolaemic and hypolipidaemic potential. Additionally, raw ginger is effective in reversing the diabetic proteinuria observed in the diabetic rats. Thus, ginger may be of great value in managing the effects of diabetic complications in human subjects.     

甜茶素提取物对STZ致高血糖大鼠的降血糖作用研究

目的 :　研究甜茶素提取物对 STZ致高血糖大鼠的降血糖效果及其降糖机制。方法 :　腹腔注射 STZ制备糖尿病大鼠模型 ,取成型的大鼠随机分阳性对照组、甜茶素提取物组和降糖灵组。同时设一正常组。灌胃 3 w后 ,测血糖、果糖胺、胰岛素和 SOD等指标。结果 :　甜茶素提取物能极显著地降低 STZ致高血糖大鼠血糖 ,增强其抗氧化能力 ,同时能刺激胰岛素的分泌。结论 :　甜茶素提取物通过刺激胰岛素的分泌来降低血糖     

Antihyperglycemic Effect of Methanol Extract of Syzygium polyanthum (Wight.) Leaf in Streptozotocin-Induced Diabetic Rats

Syzygium polyanthum (S. polyanthum), a plant belonging to Myrtaceae, is widely used in Indonesian and Malaysian cuisines. Diabetic patients in Indonesia also commonly use it as a traditional medicine. Hence, this study was conducted to investigate the antihyperglycemic effect of the methanol extract (ME) of S. polyanthum leaf and its possible mechanisms of action. To test for hypoglycemic activity, ME was administered orally to normal male Sprague Dawley rats after a 12-h fast. To further test for antihyperglycemic activity, the same treatment was administered to glucose-loaded (intraperitoneal glucose tolerance test, IPGTT) and streptozotocin (STZ)-induced diabetic rats, respectively. Hypoglycemic test in normal rats did not show significant reduction in blood glucose levels (BGLs) by the extract. Furthermore, IPGTT conducted on glucose-loaded normal rats also did not show significant reduction of BGLs. However, repeated administration of metformin and three doses of ME (250, 500 and 1000 mg/kg) for six days caused significant reduction of fasting BGLs in STZ-induced diabetic rats. The possible mechanisms of action of S. polyanthum antihyperglycemic activity were assessed by measurement of intestinal glucose absorption and glucose uptake by isolated rat abdominal muscle. It was found that the extract not only inhibited glucose absorption from the intestine but also significantly increased glucose uptake in muscle tissue. A preliminary phytochemical qualitative analysis of ME indicated the presence of tannins, glycosides, flavonoids, alkaloids and saponins. Additionally, Gas Chromatography-Mass Spectrometry (GC-MS) analysis detected squalene. In conclusion, S. polyanthum methanol leaf extract exerts its antihyperglycemic effect possibly by inhibiting glucose absorption from the intestine and promoting glucose uptake by the muscles.     

链脲佐菌素诱导糖尿病大鼠肾病模型的建立

目的评价链脲佐菌素(STZ)糖尿病大鼠肾病动物模型。方法用STZ 65 mg/kg一次性腹腔内注射方式制作糖尿病大鼠模型,60只SD大鼠随机分为正常对照组(M),糖尿病1个月组(M1)、3个月组(M2),每组20只。期间观察大鼠血糖、尿糖及一般情况变化,实验结束时,测定血肌酐、尿素氮、尿蛋白、尿白蛋白排泄率,取肾作病理及超微病理检查。结果M未见异常改变,从M1开始出现异常改变,以M2最明显。M2模型组大鼠的血肌酐、尿素氮、尿蛋白、尿白蛋白明显升高,出现肾脏肥大,病理显示明显的肾小球、肾小管病变。结论STZ诱导的糖尿病大鼠肾脏病变表现为肾小球及小管间质损害,可用作糖尿病肾病研究的动物模型。