Antihyperglycemic and antihyperlipidemic effect of Rumex patientia seed preparation in streptozotocin-diabetic rats

Background and objective:Rumex patientia (RP) could exert beneficial health effects to ameliorate metabolic diseases. The effect of subchronic feeding of RP seeds was evaluated on serum glucose and lipid profile in streptozotocin (STZ)-diabetic rats. Methods: Wistar rats were divided into control, RP-treated control, diabetic, glibenclamide-treated diabetic, and RP-treated diabetic groups. For induction of diabetes, streptozotcin was administered at a dose of 60 mg/kg. Meanwhile, RP-treated groups received RP seed powder mixed with standard pelleted food at a weight ratio of 6% for 4 weeks. Serum glucose and lipid levels were determined before the study and at 2nd and 4th weeks after the study in addition to the oxidative stress markers in hepatic tissue. Results: Serum glucose was significantly lower in RP-treated diabetic rats at 2nd and 4th weeks as compared to untreated diabetics (p < 0.05 and p < 0.01, respectively). Serum total cholesterol and triglyceride levels did not show significant reductions in RP-treated diabetic rats as compared to untreated diabetics. Serum HDL-cholesterol, however, significantly increased (p < 0.05) and LDL-cholesterol showed a significant reduction (p < 0.05) in RP-treated diabetic rats as compared to untreated diabetics (p < 0.05). RP also attenuated the increased malondialdehyde (MDA) content and reduced activity of superoxide dismutase (SOD) in hepatic tissue. Conclusion: Subchronic treatment of diabetic rats with RP could lessen the abnormal changes in blood glucose level and to improve lipid profile regarding HDL- and LDL-cholesterol in part due to its attenuation of lipid peroxidation in hepatic tissue.     

Chlorophytum borivilianum Root Extract Maintains near Normal Blood Glucose,Insulin and Lipid Profile Levels and Prevents Oxidative Stress in the Pancreas of Streptozotocin-Induced Adult Male Diabetic Rats

The effect of C. borivilianum root on blood glucose, glycated hemoglobin (HbAIc), insulin and lipid profile levels in diabetes mellitus are not fully understood. This study therefore investigated the effect of C. borivilianum root on the above parameters and oxidative stress of the pancreas in diabetes. Methods: C. borivilianum root aqueous extract (250 and 500 mg/kg/day) was administered to streptozotocin (STZ)-induced male diabetic rats for 28 days. Body weight, blood glucose, HbA1c, insulin, lipid profile levels and glucose homeostasis indices were determined. Histopathological changes and oxidative stress parameters i.e. lipid peroxidation (LPO) and antioxidant enzymes activity levels of the pancreas were investigated. Results: C. borivilianum root extract treatment to diabetic rats maintained near normal body weight, blood glucose, HbA1c, lipid profile and insulin levels with higher HOMA-β cell functioning index, number of Islets/pancreas, number of β-cells/Islets however with lower HOMA-insulin resistance (IR) index as compared to non-treated diabetic rats. Negative correlations between serum insulin and blood glucose, HbA1c, triglyceride (TG) and total cholesterol (TC) levels were observed. C. borivilianum root extract administration prevented the increase in lipid peroxidation and the decrease in activity levels of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) with mild histopathological changes in the pancreas of diabetic rats. Conclusions: C. borivilianum root maintains near normal levels of these metabolites and prevented oxidative stress-induced damage to the pancreas in diabetes.     

银杏叶提取物对糖尿病大鼠脂代谢及巨噬细胞功能的影响

目的： 研究银杏叶提取物（EGb）对2型糖尿病大鼠脂代谢及巨噬细胞功能的影响。 方法： SD大鼠分4组：正常对照组、高脂组、糖尿病组、EGb治疗组，治疗结束取血测血糖、血脂、血胰岛素并分别灌取4组大鼠腹腔及肺泡巨噬细胞，测定巨噬细胞内超氧化物歧化酶（SOD）、一氧化氮（NO）及丙二醛（MDA）的水平，并用RT-PCR方法测定大鼠肺泡巨噬细胞内CD36、PPARγ的基因表达水平。 结果： 糖尿病大鼠血糖、血胰岛素、总胆固醇（TC）、总甘油三酯（TG）、低密度脂蛋白胆固醇（LDL-C）升高，经EGb治疗后，血糖、血胰岛素、TC、TG、LDL-C明显降低；糖尿病大鼠腹腔及肺泡巨噬细胞内SOD活性下降、NO及MDA含量增高，经EGb治疗后，SOD活性升高、NO2-/NO3-及MDA含量下降；糖尿病大鼠肺泡巨噬细胞CD36基因表达升高，PPARγ基因表达升高，经EGb治疗后，CD36基因表达继续升高但无显著差异、PPARγ基因表达继续升高。 结论： EGb对糖尿病大鼠巨噬细胞脂质过氧化有较好的拮抗作用，并能降低一氧化氮含量，从而改善糖尿病时巨噬细胞功能；EGb可提高2型糖尿病大鼠肺泡巨噬细胞CD36、PPARγ基因的表达水平，这可能是其降血脂和改善胰岛素抵抗的机制之一。     

表没食子儿茶素没食子酸酯( EGCG) 对免疫性肝损伤的保护作用及其机制研究

目的:探讨表没食子儿茶素没食子酸酯(EGCG)对雷公藤甲素(TP)诱导的免疫性肝损伤的保护性作用及其作用机制。方法:雌性C57BL/6 小鼠随机分为4 组,即正常对照组、EGCG 对照组、TP 组、EGCG 治疗组。以赖氏法检测血清中ALT 水平,以分光光度法检测肝匀浆中丙二醛(MDA)、超氧化物歧化酶(SOD)和还原型谷胱甘肽(GSH)的变化情况,以HE染色观测小鼠肝脏组织形态学变化,以ELISA 方法检测肝脏中白细胞介素(IL)-17 和IL-6 的表达水平,以Western blot 方法检测肝脏中Toll 样受体4(TLR4)的表达情况。结果:TP 组小鼠血清转氨酶水平明显高于正常对照组(P<0.005),EGCG 对照组与正常对照组比较无变化(P>0.05),而EGCG 治疗组小鼠血清转氨酶水平与TP 组相比下降明显(P<0.005)。TP 组小鼠肝脏病理切片示较多肝细胞坏死和中性粒细胞浸润,EGCG 对照组和正常对照组小鼠肝脏形态学基本正常,EGCG 治疗组示肝细胞炎症坏死程度较TP 组有大幅减轻。TP 组小鼠肝脏中MDA、IL-17 及IL-6 水平明显高于正常对照组(P<0.005),而SOD和GSH 水平明显低于正常对照组(SOD,P<0.05;GSH,P<0.005),EGCG 对照组与正常对照组比较无变化(P>0.05),EGCG 治疗组小鼠肝脏中MDA、IL-17 及IL-6 水平均下降明显(P<0.005),而SOD 和GSH 水平均增高,与TP 组比较有显著性差异(SOD,P<0.05;GSH,P<0.005)。TP 组肝脏TLR4 蛋白表达水平高于正常对照组,EGCG 对照组与正常对照组比较无变化(P>0.05),而EGCG 治疗组TLR4 水平显著降低。结论:EGCG 对TP 所致小鼠肝损伤有明显的保护作用,可能与其抗氧化作用及对炎症因子的调节有关。     

Antihyperglycemic and antioxidant activities of alcoholic extract of Commiphora mukul gum resin in streptozotocin induced diabetic rats

Background and objectives: The present study investigated the effect of Commiphora mukul ethanol extract gum resin (CMEEt) on streptozotocin (STZ) induced diabetic rats by measuring fasting blood glucose, plasma insulin, plasma lipid profile, atherogenic index, hepatic lipid peroxidation (LPO), protein oxidation (PO) and activities of enzymatic antioxidants. Methods: Wistar albino rats were divided into 4 groups, normal control group, CM-treated control group, diabetic control group and CM-treated diabetic group. For induction of diabetes, STZ was administered at a dose of 55 mg/kg body weight, meanwhile CM-treated groups were administered CMEEt at a dose of 200 mg/kg body weight for 60 days. Body weight, plasma glucose and insulin levels were determined in different experimental days, after end of the experimental period the plasma lipid profile and antioxidant enzymes were determined in hepatic tissue. Results: Increase in plasma glucose, total cholesterol (TC), triglycerides (TG), low density lipoprotein cholesterol (LDL-C), very low density lipoprotein cholesterol (VLDL-C), hepatic LPO and PO levels with decrease in plasma high density lipoprotein cholesterol (HDL-C), insulin, hepatic reduced glutathione (GSH) content and activities of antioxidant enzymes namely, glutathione peroxidase (GPX), glutathione reductase (GR), glutathione-S-transferase (GST), superoxide dismutase (SOD) and catalase (CAT) were the salient features observed in diabetic rats. On the other hand, oral administration of CMEEt at a dose of 200 mg/kg for 60 days resulted in the prevention of above mentioned abnormalities. Conclusion: The results suggest that CMEEt could be beneficial in the treatment of diabetes, characterized by atherogenous lipoprotein profile, aggravated antioxidant status and impaired glucose metabolism and in their prevention.     

银杏叶提取物对实验性2型糖尿病大鼠肝脏的保护作用

目的： 研究银杏叶提取物(EGB)对实验性2型糖尿病大鼠肝脏损伤的影响及机制。方法: 雄性SD大鼠39只，随机分为4组: 正常对照组、高脂组、糖尿病对照组和EGB治疗组。采用高脂饮食加链脲佐菌素（STZ） 诱导2型糖尿病大鼠模型， EGB治疗组给予EGB 8 mg·kg^-1·d^-1治疗8周。用光镜和透射电镜观察EGB对2型糖尿病大鼠肝组织的形态学改变，并检测肝组织中超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、谷胱甘肽还原酶(GSH-PX)和总一氧化氮合酶(NOS)、诱导型一氧化氮合酶(iNOS)的活性及MDA、NO含量。结果: 糖尿病组光镜下主要表现为肝细胞脂肪变性明显，出现大量脂肪空泡，胞浆内糖原颗粒减少或消失。电镜下主要表现为肝细胞核固缩，胞浆内含大量脂滴，细胞器明显减少，贮脂细胞明显增生，胶原纤维增生。肝组织内GSH-PX、SOD、CAT活性明显低于正常对照组，MDA、 NO含量及总NOS、iNOS 活性显著高于正常对照组； EGB治疗组肝脏组织病理改变较轻，GSH—PX、SOD、CAT 活性明显高于糖尿病组，MDA、NO含量及总NOS、iNOS 活性显著低于糖尿病组。结论: EGB对2型糖尿病大鼠的肝脏具有保护作用、抗脂质过氧化作用和抑制NO的过多产生可能在其中起重要作用。     

Garlic (Allium sativum) attenuate glomerular glycation in streptozotocin-induced diabetic rats: A possible role of insulin

Objective: This study investigated the effect of fresh garlic aqueous extract on glomerular glycation in streptozotocin-induced diabetic rats. Method: Serum insulin and glucose, in addition to renal corpuscles and erythrocyte hemoglobin glycation were determined in normal saline-treated normal rats (NS-NR), normal saline-treated diabetic rats (NS-DR) and garlic-treated diabetic rats (G-DR). Results: Compared to NS-NR, NS-DR showed significant decrease in serum insulin and increase in serum glucose and hemoglobin glycation. NS-DR also showed intense, diffused glomerular periodic acid Schiff activity. Compared to NS-DR, G-DR showed significant increase in serum insulin and decrease in serum glucose and hemoglobin glycation. Furthermore, the G-DR glomerular periodic acid Schiff activity and distribution was almost restored to that observed in NS-NR. Conclusion: Garlic may attenuate glomerular glycation in streptozotocin-induced diabetic rats. This effect could be partially mediated via euglycemia induced by revitalization of endogenous insulin.     

Vascular mechanisms of cyanidin-3-glucoside response in streptozotocin-diabetic rats

Background and objective: Considering the high incidence of cardiovascular disorders in diabetes mellitus and some evidence on the antioxidant and antidiabetic potential of cyanidin-3-glucoside (C3G), this study was conducted to evaluate the possible beneficial effect of C3G administration on vascular reactivity of isolated thoracic aorta in diabetic rats and some of its underlying mechanisms. Materials and methods: Male diabetic rats received C3G (10 mg/kg; i.p.) on alternate days for 8 weeks one week after streptozotocin (STZ) diabetes induction. Results: It was found out that treatment of diabetic rats with C3G exerted a hypoglycaemic effect and attenuated the increased malondialdehyde (MDA) content and reduced the activity of superoxide dismutase (SOD) in aortic tissue. Maximum contractile response of endothelium-intact aortic rings to phenylephrine (PE) was significantly lower in C3G-treated diabetic rats relative to untreated diabetics and endothelium removal abolished this difference. Meanwhile, endothelium-dependent relaxation to acetylcholine (ACh) was significantly higher in C3G-treated diabetic rats as compared to diabetic group. Conclusion: Chronic treatment with C3G may prevent some diabetes-related changes in vascular reactivity observed in diabetic rats directly and/or indirectly due to its hypoglycaemic effect and attenuation of lipid peroxidation and through endothelial-derived factors.     

核黄素预处理减轻大鼠肝缺血再灌注损伤

目的: 探讨核黄素对肝缺血再灌注损伤的影响及其机制。方法: 将24只SD大鼠随机分为3组,每组8只。假手术对照组(sham组)和缺血再灌注组(I/R组)大鼠喂以正常饲料,核黄素预处理组(R+I/R组)大鼠补充核黄素。喂养4周后,阻断大鼠肝门1 h,再灌注1 h建立I/R模型。术后采血并收集肝脏标本,分别检测血清及肝组织中超氧化物歧化酶(SOD)活性、丙二醛(MDA)水平和血清丙氨酸氨基转移酶(ALT)和天门冬氨酸氨基转移酶(AST)的活性;蛋白印迹法检测肝组织血红素加氧酶-1(HO-1) 表达情况;HE染色观察肝组织病理学改变。结果: 与sham组比较,I/R组大鼠血清AST、ALT活性及MDA水平均明显升高,SOD活性显著降低(P<0.01);肝组织中SOD活性亦明显下降(P<0.01),MDA水平及HO-1蛋白表达则显著增高(P<0.05)。而R+I/R组较I/R组大鼠血清AST、ALT活性及MDA水平均明显下降,SOD活性显著增强(P<0.01);肝组织中MDA水平亦明显降低,SOD及HO-1蛋白表达显著增高(P<0.01)。组织切片显示I/R组大鼠肝细胞肿胀,炎症细胞浸润,小叶结构紊乱;R+I/R组大鼠肝细胞仅轻度肿胀,几乎无气球样变,小叶结构清晰。结论: 核黄素预处理对缺血再灌注肝脏具有显著的保护作用,其作用机制可能与核黄素通过降低MDA水平、提高SOD活性及HO-1蛋白表达,增强肝脏的抗氧化能力,减轻脂质过氧化反应有关。     

甘草酸二铵对肝纤维化大鼠肝脏脂质过氧化与间质性胶原酶活性的影响

目的：探讨甘草酸二铵影响纤维化肝脏脂质过氧化与间质性胶原酶活性的抗肝纤维化作用机制。 方法： 以四氯化碳(CCl4)皮下注射与高脂肪低蛋白饮食复合因素诱导大鼠肝纤维化模型，而后予以甘草酸二铵口服治疗，正常大鼠与模型对照组给予等量生理盐水。HE染色与胶原染色观察大鼠肝组织炎性坏死与胶原沉积病理改变，按试剂盒方法检测血清肝功能（ALT、AST、Alb与总胆红素等）变化，检测肝组织主要过氧化损伤指标：超氧化物歧化酶（SOD）活性, 丙二醛（MDA）含量，谷胱甘肽（GSH）含量与谷胱甘肽过氧化物酶（GSH-Px）活性，水解法测定肝组织羟脯氨酸含量，酶底物反应法分析肝组织间质性胶原酶活性变化，RT-PCR法分析肝组织Ⅰ型前胶原基因表达。 结果： 与正常大鼠相比，模型大鼠肝脏有明显胶原沉积与肝纤维化，伴有不同程度的肝细胞炎性损伤坏死；甘草酸二铵药物组明显减轻模型大鼠肝组织损伤坏死与胶原沉积等病理变化。模型大鼠肝功能指标,包括血清总胆红素含量、ALT与AST活性、白蛋白含量均明显减少（P<0.01）。药物组大鼠血清总胆红素含量、AST与ALT活性显著低于模型组（P<0.05），而白蛋白含量高于模型组（P<0.05）。此外，药物组大鼠肝组织羟脯氨酸含量(151.3±37.3 μg/g)明显少于模型组(170.9±15.3 μg/g，P<0.05)，Ⅰ型前胶原基因表达弱于模型组（P<0.05）；肝组织MDA含量(1.96±0.23 μmol/g)低于模型组(2.44±0.32 μmol/L, P<0.05)，SOD水平(19.60±0.97 NU/g)高于模型组(20.60±0.33 NU/g，P<0.05)，GSH含量(47.0±9.1 g/g)与GSH-Px活性(53.1±4.1 U/g)高于模型组(41.2±3.5 g/g；46.7±6.1 U/g，P<0.05)；肝组织间质性胶原酶活性(43.89±7.74 U)高于模型组(32.01±2.75 U，P<0.05)。 结论： 甘草酸二铵有明显抗肝纤维化大鼠肝脏脂质过氧化损伤与提高肝组织间质性胶原酶活性的作用，该作用是药物抗肝纤维化的重要机制。     

Lycopene ameliorates renal function in rats with streptozotocin-induced diabetes

Aim: To study the effect of lycopene on ameliorating renal function of diabetic nephropathy. Methods: Sixty male SD rats were divided into four groups: normal untreated (NC-U), normal treatment (NC-L), diabetes untreated (DM-U) and diabetes treatment (DM-L). DM was prepared by a single injection of STZ (70 mg/kg, intraperitoneally) dissolved in 0.1 M citrate buffer (pH 4.5). DM-U and NC-U rats received control diet; DM-L and NC-L rats received lycopene. After treated with lycopene for 8 weeks, blood was obtained for analyzing plasma lipid profiles, glucose and renal function. The kidneys were used to determine SOD activity, malondialdehyde (MDA) level, processed for histological examination and western blot. Results: Treatment of diabetic rats with lycopene decreased the values of blood urea nitrogen, 24 h urea protein and creatinine. The serum lipids like TC, TG, and LDL were decreased and HDL was increased in DM-L rats when compared with those of diabetic rats. Administration of lycopene decreased the levels of MDA content and expression of CTGF, increased Akt/PKB phosphorylation and SOD activity in diabetic renal tissues. Conclusions: Lycopene protects against development of diabetic nephropathy and ameliorates renal function via improving oxidative status and regulating p-Akt and CTGF.     

白藜芦醇对糖尿病大鼠心功能障碍及酸性鞘磷脂酶-神经酰胺通路的影响

目的:观察白藜芦醇(RSV)对糖尿病大鼠心功能障碍的影响并探讨其与酸性鞘磷脂酶-神经酰胺通路的关系。方法:通过一次性腹腔注射小剂量链脲佐菌素(STZ;30 mg/kg)联合高脂饮食饲养12周构建2型糖尿病(T2DM)大鼠模型。实验分为正常对照(control)组、T2DM组、T2DM+RSV组(灌胃给予糖尿病大鼠白藜芦醇100 mg·kg~(-1)·d~(-1))和RSV组(正常大鼠灌胃给予同等容量RSV),共灌胃12周,每周称量体重并调整给药剂量。实验结束后,釆用小动物M型超声检测模型大鼠心脏功能、形态和结构的变化;颈动脉插管检测血流动力学变化;生化方法检测血清中糖、脂水平以及心脏组织中超氧化物歧化酶(SOD)活性和丙二醛(MDA)含量;油红O染色和天狼星红染色分别观察心脏组织中脂肪堆积和心肌纤维化情况;高效液相质谱法检测心脏组织中神经酰胺(ceramide)含量;Western blot检测酸性鞘磷脂酶(ASMase)和过氧化物酶增殖体激活受体γ辅激活因子1α(PGC~(-1)α)的蛋白表达。结果:T2DM组大鼠空腹血糖、甘油三酯、胆固醇及低密度脂蛋白胆固醇水平均较control组显著升高,心功能显著降低(P0.05);T2DM组大鼠心脏组织中脂肪堆积、MDA含量显著增加(P0.05),SOD活性、ATP水平和PGC~(-1)α蛋白表达均显著降低(P0.05),且出现明显心肌纤维化;给予白藜芦醇治疗12周可显著改善以上指标的异常变化,同时,显著下调糖尿病大鼠升高的心肌ASMase蛋白和ceramide水平。结论:白藜芦醇可显著改善糖尿病诱导的大鼠心功能障碍和心肌纤维化,其机制可能与抑制ASMase-ceramide通路有关。     

银杏叶提取物对糖尿病大鼠睾丸损伤的作用

目的:研究银杏叶提取物(GBE)对糖尿病所致的睾丸损伤的作用及其机制。方法:用光镜及透射电镜观察链脲佐菌素(STZ)诱导的糖尿病1个月大鼠睾丸的形态学改变,并测定睾丸组织丙二醛(MDA)、NO产物NO₂^-/NO₃^-的含量及超氧化物歧化酶(SOD)、一氧化氮合酶(NOS)的活性。 结果:①糖尿病大鼠睾丸组织光镜下主要表现为睾丸曲细精管萎缩、变形及生精上皮脱落,透射电镜下主要见到支持细胞浆内内质网扩张、脂滴空泡形成,溶酶体明显减少,银杏叶组大鼠睾丸组织光镜、透射电镜下上述病变明显改善。②睾丸组织的MDA、NO₂^-/NO₃^-含量及tNOS和iNOS活性银杏叶组低于糖尿病组,SOD活性银杏叶组高于糖尿病组。 结论:GBE对糖尿病所致的睾丸损伤有明显的保护作用,其作用机制与提高SOD活力减少MDA产生,抑制iNOS活力减少NO产生有密切关系。     

糖尿病大鼠心肌MDA含量、SOD和Na￣ -K￣ -ATP酶活性的变化

实验用四氧嘧啶破坏Ｗｉｓｔａｒ大鼠胰腺诱发糖尿病模型，观察糖尿病人鼠心肌组织ＭＤＡ含量，ＳＯＤ和Ｎａ＋－Ｋ＋－ＡＴＰ酶活性的变化以及氧自由基清除剂（ＶｉｔＥ．亚硒酸钠）对糖尿病大鼠心肌的保护作用。结果表明：（１）糖尿病大鼠心肌组织ＭＤＡ含量显著增加（Ｐ＜０．０５），而心肌细胞膜上Ｎａ＋－Ｋ＋一ＡＴＰ酶的活性显著下降（Ｐ＜０．０１）．（２）ＶｉｔＥ和亚硒酸钠能显著降低糖尿病大鼠心肌组织ＭＤＡ含量，并能提高ＳＯＤ和Ｎａ＋－Ｋ＋－ＡＴＰ酶活性。以上结果说明糖尿病大鼠心肌组织的脂质过氧化反应可能是导致心肌细胞膜上Ｎａ＋－Ｋ＋－ＡＴＰ酶活性下降的原因之一     

辛伐他汀对2型糖尿病患者氧化应激的影响

为探讨辛伐他汀对2型糖尿病患者氧化应激的抑制作用及对血脂的影响,观察了辛伐他汀及安慰剂对168例2型糖尿病患者血清丙二醛(MDA)、超氧化物歧化酶(SOD)和血脂的影响.结果表明,与对照组相比,2型糖尿病患者血清SOD水平下降,MDA水平上升;辛伐他汀治疗12周后,患者血清SOD水平上升,而MDA水平明显下降,与治疗前相比有显著性差异(P＜0.05),安慰剂处理前、后患者血清SOD及MDA水平无显著性差异(P＞0.05).辛伐他汀治疗组TG、TC、LDL-C和VLDL-C水平较治疗前下降,而HDL-C水平与治疗前相比上升,有显著性差异(P＜0.05).安慰剂处理前、后患者血脂谱无显著性差异(P＞0.05).由此可见,辛伐他汀对2型糖尿病患者氧化应激有明显的抑制作用,且有益于血脂的调节.     

当归多糖治疗小鼠乙醇性肝损伤中丙二醛、超氧化物歧化酶及谷胱甘肽过氧化物酶的变化及意义

目的:探讨当归多糖治疗小鼠乙醇性肝损伤中丙二醛(MDA)、超氧化物歧化酶(SOD)及谷胱甘肽过氧化物酶(GSHPx)的变化及意义。方法:通过一次性高浓度乙醇灌胃建立小鼠乙醇性肝损伤模型,之后连续腹腔注射当归多糖6 d,血清生化检测MDA、SOD及GSH-Px,光镜观察肝形态结构变化。结果:小鼠乙醇性肝损伤后,血清MDA显著增高,SOD及GSH-Px显著下降,同时肝组织结构呈弥漫性脂肪变性损伤。用当归多糖治疗后,伴随肝组织结构的修复,血清MDA显著下降,SOD及GSH-Px增高。结论:当归多糖可通过阻断膜脂质过氧化起到保护肝细胞的作用,血清MDA、SOD及GSHPx水平的变化对判断肝的损害程度、病情发展、评估预后有一定的意义。     

实验性糖尿病肺形态学及氧自由基研究

目的:了解早期糖尿病肺形态学及氧化应激的变化。方法:应用体视学方法对四氧嘧啶诱导的糖尿病28d大鼠肺进行定量研究、观察超微结构变化并测定血清和肺组织的超氧化物歧化酶(SOD)活性及丙二醛(MDA)含量。结果:糖尿病大鼠肺泡体密度和平均截线长度减少,肺泡壁体密度、肺泡表面积密度、肺泡数密度、肺泡面数密度和肺泡比表面增加。糖尿病大鼠Ⅱ型肺泡细胞粗面内质网扩张,其体密度、面密度、平均截面积和平均周长增加,而比表面减少。肺上皮和毛细血管基底膜增厚。糖尿病大鼠血清SOD活性下降,MDA含量增加;肺组织MDA含量明显升高。结论:糖尿病早期大鼠肺已发生形态学变化且受到氧化应激的危害,提示肺脏是糖尿病损害的"靶器官"之一。     

荞麦叶总黄酮对糖尿病并高脂血症大鼠血糖、血脂及血液流变性的影响

目的 :研究荞麦叶总黄酮 (TFBL)对糖尿病并高脂血症大鼠血糖、血脂、脂质过氧化产物丙二醛 (MDA)及血液流变性的影响。方法 :用链脲佐菌素和高脂饲料诱发大鼠糖尿病及高脂血症 ,口服TF BL治疗 12周 ,观察其对糖尿病并高脂血症大鼠的治疗作用。结果 :TFBL能明显降低高脂血症和糖尿病大鼠的血清LDL C ,升高HDL C ,降低血糖 ,改善糖耐量。降低血清MDA含量 ,降低血粘度。结论 :TFBL具有降血糖、调血脂、抗氧化、改善胰岛素抵抗和血液流变性的作用     

Effects of vitamin E supplementation on oxidative stress in streptozotocin induced diabetic rats: investigation of liver and plasma

This experimental study was designed to investigate the effects of vitamin E supplementation, especially on lipid peroxidation and antioxidant status elements 3/4 namely, glutathione (GSH), CuZn superoxide dismutase (CuZn SOD), and glutathione peroxidase (GSH Px), both in blood and liver tissues of streptozotocin (STZ) diabetic rats. The extent to which blood can be used to reflect the oxidative stress of the liver is also investigated. In diabetic rats, plasma lipid peroxide values were not significantly different,from control,whereas erythrocyte CuZn SOD (p < 0.01), GSH Px (p < 0.001) activities and plasma vitamin E levels (p < 0.001), were significantly more elevated than controls. Vitamin E supplementation caused significant decreases of erythrocyte GSH level (p < 0.01) in control rats and of erythrocyte GSH Px activity (p < 0.05) in diabetic rats. Liver findings revealed significantly higher lipid peroxide (p < 0.001) and vitamin E (p < 0.01) levels and lower GSH (p < 0.001), CuZn SOD (p < 0.001) and GSH Px (p < 0.01) levels in diabetic rats. A decreased hepatic lipid peroxide level (p < 0.01) and increased vitamin E/lipid peroxide ratio (p < 0.001) were observed in vitamin E supplemented, diabetic rats. A vitamin E supplementation level which did not cause any increase in the concentration of the vitamin in the liver or blood, was sufficient to lower lipid peroxidation in the liver. Vitamin E/lipid peroxide ratio is suggested as an appropriate index to evaluate the efficiency of vitamin E activity,independent of tissue lipid values. Further, the antioxidant components GSH, GSH Px and CuZn SOD and the relationships among them, were affected differently in the liver and blood by diabetes or vitamin E supplementation.     

Effect of Chronic Administration of Hexane Extract of Byrsonima Crassifolia Seed on B-Cell and Pancreatic Oxidative Parameters in Streptozotocin-Induced Diabetic Rat

Background

In Mexican traditional medicine, the seeds of Byrsonima crassifolia have been used in the treatment of diabetes, rheumatism and for wound healing. The aim was to evaluate the effect of seeds of B. crassifolia on insulin release from the pancreatic beta cells in streptozotocininduced diabetic rats.

Materials and Methods

In the present study, we evaluated the beneficial effect of seeds B. crassifolia streptozotocin-induced type 1 diabetic rats. Insulin level; insulin sensitivity index, insulin content in pancreas, malonaldehyde, nitric oxide contents, oxidative stress parameters were assayed. Serum glucose levels were determined by the glucose oxidase method. To determine the insulin releasing activity, after extract treatment, the pancreas was excised. Pancreatic sections were processed for examination of insulin-releasing activity using an imunocytochemistry kit.

Results

Administration of the hexane extract (200 and 400 mg/kg), exhibited a significant reduction in serum glucose. Administration of streptozotocin decreased the number of beta cells with insulin secretory activity in comparison with intact rats; but treatment with the B. crassifolia seed extract increased significantly the activity of the beta cells in comparison with the diabetic control rats. The extract decreased serum glucose in streptozotocin-induced diabetic rats and increased insulin release from the beta cells of the pancreas.

Conclusion

These finding suggest that B. crassifolia seed has beneficial effect for diabetes through decreasing blood glucose and lipid levels, increasing insulin sensitivity index and insulin content, up-regulating antioxidant enzyme activity and decreasing lipid peroxidation.