低剂量雷帕霉素对糖尿病肾病大鼠肾组织中VEGF表达的影响

目的探讨糖尿病大鼠肾组织中血管内皮生长因子(VEGF)的表达,以及雷帕霉素对其表达的影响。方法将SD大鼠随机分为正常对照组(A组)、糖尿病组(B组)和雷帕霉素组(C组),用链脲佐菌素(STZ)诱导SD大鼠制备糖尿病模型。治疗8周后处死大鼠,采用RT-PCR法检测3组大鼠肾脏组织中VEGF RNA表达,Western印迹法检测VEGF蛋白表达,同时测定大鼠尿白蛋白/肌酐、平均肾小球体积、肾质量指数等。结果 B组和C组大鼠肾组织中VEGF的表达水平均较A组升高(P<0.05),而C组VEGF的表达水平低于B组(P<0.05);VEGF的表达水平与尿白蛋白/肌酐、平均肾小球体积呈正相关(P<0.05)。结论 VEGF参与糖尿病大鼠肾脏损害的发生,雷帕霉素可以通过下调VEGF的表达发挥肾脏保护作用。     

低剂量雷帕霉素对糖尿病肾病大鼠nephrin表达的影响

目的 探讨低剂量雷帕霉素对糖尿病肾病大鼠足细胞超微结构及nephrin表达的影响.方法 将22只雄性SD大鼠随机分为正常组(C组,n=7),糖尿病组(D组,n=7),雷帕霉素治疗组(R组,n=8).造模后第5周起R组大鼠给予雷帕霉素1 mg/kg/d灌胃,C组和D组给予等体积的羧甲基纤维素溶液灌胃.12 w末,观察各组大鼠血糖、24h尿蛋白量、体重校正的内生肌酐清除率(Ccr),以及透射电镜观察足细胞的超微结构;并通过免疫组化、RT-PCR检测nephrin的蛋白及其mRNA的表达.结果 至12 w末,与C组相比,D组大鼠血糖、Ccr、24 h尿蛋白量增加(P＜0.01),nephrin蛋白及其mRNA表达下调(P＜0.01);R组Ccr及24 h尿蛋白量较D组降低(P＜0.01),nephrin蛋白及其mRNA表达增加(P＜0.01).结论 低剂量雷帕霉素可能通过上调nephrin表达改善足细胞超微结构,从而延缓糖尿病肾病的进展.     

雷帕霉素靶分子在糖尿病肾病发病机制中的作用

哺乳动物雷帕霉素靶分子位于胰岛素/胰岛素样生长因子通路的下游,同时接受营养信号和能量信号,参与细胞、器官和生物体肥胖的调控,引起胰岛素抵抗,促进血管内皮细胞生长因子的表达,可能在2型糖尿病及糖尿病肾病的发生发展中起重要的作用.     

血管内皮细胞生长因子基因多态性与糖尿病肾病的相关性

目的研究血管内皮细胞生长因子（VEGF）基因多态性与糖尿病肾病（DN）的关系。方法单纯2型糖尿病（DM）组76例,DN组81例,健康对照（NC）组60例。UNIQ-10柱提取全血基因组DNA。标本基因型的判断用聚合酶链反应-限制性酶切片断长度多态性技术。Hardy-Weinberg平衡法检验各组基因频率的群体代表性。结果（1）DN组VEGF-460和＋405CC基因型频率和C等位基因频率明显高于DM组和NC组。（2）-460位点CC基因型DN患病率明显高于CT和TT基因型。＋405位点CC基因型DN患病率明显高于CG和GG基因型。（3）显示VEGF-460和＋405基因多态性均为DN发生的独立危险因素。结论（1）VEGF-460C/T基因多态性与DN发生有关。C等位基因可能是DN易感基因。（2）VEGF＋405G/C基因多态性与DN发生有关。C等位基因可能是DN的易感基因。     

雷帕霉素对糖尿病肾病大鼠病理结构及结缔组织生长因子表达的影响

目的 观察雷帕霉素对糠尿病肾病(DN)的保护作用.方法 应用链脲佐菌素(STZ)建立糖尿病大鼠模型.24只SD大鼠随机分为3组:对照组、糖尿病组、雷帕霉素组.第5周起雷帕霉素组予雷帕霉素1 mg·kg-1·d-1干预8 w.12 w末观察各组大鼠血糖、内生肌酐清除率(Ccr)、24 h尿微量白蛋白(24hUalb)、肾重/体重等的变化.光镜观察肾组织病理变化并测定肾小球平均体积及系膜基质扩张指数(EMMI).RT-PCR及免疫组化法检测肾皮质结缔组织生长因子(CTGF)mRNA及蛋白表达.结果 与对照组相比,糖尿病组及雷帕霉素组大鼠血糖、Ccr、24hUalb均显著上升,大鼠肾脏明显肥大,肾小球平均体积、EMMI、毛细血管基底膜厚度均显著增加;肾皮质CTGFmRNA及蛋白表达显著上调.雷帕霉素干预后,上述指标除血糖外均部分被抑制.结论 小剂量雷帕霉素能够减轻肾脏肥大,抑制系膜外基质聚集,下调CTGF的表达,延缓DN的进展.     

糖尿病患者植入雷帕霉素药物洗脱支架的疗效分析

目的:评价糖尿病对雷帕霉素药物洗脱支架临床疗效的影响。方法:选择2002年12月至2005年5月应用雷帕霉素药物洗脱支架(Cypher)的冠心病合并糖尿病患者262例(糖尿病组)和非糖尿病患者262例(对照组),平均随访8个月,患者均复查冠状动脉造影,分析不良心脏事件(心性死亡,急性心肌梗死或靶病变重建)和冠状动脉造影复查结果,评价糖尿病对Cypher支架临床近远期疗效的影响。结果:1.2组支架植入成功率均为100%,糖尿病组无死亡,6例于术后第2天发生急性心肌梗死,对照组无死亡,11例于随访6个月时发生急性心肌梗死;2.复查冠状动脉造影显示糖尿病组和对照组晚期管腔绝对内径丢失分别为(0.06±0.02)mmvs(0.04±0.02)mm(P>0.05),相对内径丢失分别为(2.32±0.19)%vs(1.63±0.14)%(P=0.03)。因再狭窄行靶血管重建者分别为33例(12.60%)和26例(9.92%)(P>0.05)。回归分析显示,相关血管大小和相对管腔内径丢失与再狭窄有关。结论:糖尿病患者应用Cypher支架安全有效,但相对内径丢失明显,糖尿病合并小血管可能是雷帕霉素药物洗脱支架再狭窄的影响因素。     

雷帕霉素对KKAy小鼠体重及胰岛素抵抗的影响

目的 探讨雷帕霉素对KKAy小鼠体重及胰岛素抵抗(IR)的影响.方法 16周KKAy小鼠34只,随机分为对照组(NC组,12只)、雷帕霉素治疗组(R组,12只)、胰岛素治疗组(Ins组,10只),6只同龄C57BL与5只KKAy小鼠作为治疗前对照.结果 治疗前KKAy小鼠体重、血糖、TG明显高于C57BL小鼠(体重36.2±1.9 g vs 29.3±1.0 g;血糖13.4±1.7 mmol/L vs 7.8±0.5 mmol/L;TG1.59±0.16 mmol/L vs 0.75±0.09 mmol/L;P均＜0.01).治疗4周后R组体重(33.7±2.3 g),低于NC组(38.2±1.5 g)和Ins组(37.4±1.1 g),差异有统计学意义(P均＜0.05);R组血糖(17.2±7.3 nmol/L),低于NC组(29.1±3.2 mmol/L),差异有统计学意义(P＜0.05);治疗8周后R组体重(32.2±3.1 g),低于NC组(39.3±2.8 g),差异有统计学意义(P＜0.05);血糖(18.2±3.7 mmol/L),低于NC组(24.4±5.1 mmol/L),差异无统计学意义(P=0.06).胰岛素敏感试验表明R组在注射胰岛素60 min后,血糖降幅明显大于NC组(4.88±0.73 mmol/L vs 2.65±2.12 mmol/L,P＜0.05).结论 雷帕霉素可减轻KKAy小鼠体重、改善IR、降低血糖.     

胰岛素生长因子-1在2型糖尿病肾病进展中的作用

目的探讨胰岛素生长因子-1(IGF-1)在2型糖尿病肾病(DN)发生发展中的作用。方法根据尿白蛋白排泄率(UAER)将46例DN患者分为早期糖尿病肾病组(EDN组)20例、临床糖尿病肾病组(CDN组)26例,另择32例健康查体者作为正常对照组(NC组),采用ELISA法检测各组血清和尿中的IGF-1水平,同时检测各组空腹血糖(FPG)、餐后血糖(PPG)、糖化血红蛋白(HbA1c)、血肌酐(SCr)等相关临床指标。结果①EDN组、CDN组较NC组血清IGF-1水平明显升高(P<0.01);与EDN组比较,CDN组尿IGF-1水平升高,NC组降低(P均<0.01)。②相关性分析显示,各组血清IGF-1水平与FPG、PPG呈负相关(P<0.01或<0.01),尿IGF-1水平与FPG、PPG、HbA1c、SCr无显著相关性(P均>0.05)。结论血清和尿IGF-1水平的变化说明IGF-1可能参与2型DN的发生与发展。     

强化治疗在延缓糖尿病肾病进展中的作用

<正>所谓的强化治疗是指使糖尿病患者血糖(餐前、餐后及糖化血红蛋白)、血压、血脂控制在较佳水平的治疗。英国前瞻性糖尿病研究小组(UKPDS)报道:在强化治疗组(包括糖尿病肾病)微血管并发症发生的风险下降25%(P=0.0099);另有资料表明,非糖尿病肾衰竭的患者不经意接受了患有轻微糖尿病肾病的供肾,移植后,供肾糖尿病肾病的病变可以消失。表明强化血糖控制对延缓(或逆     

2型糖尿病肾病患者肾组织中血管内皮细胞生长因子及其受体的变化

目的了解血管内皮细胞生长因子(VEGF)及其受体(VEGF-R)在2型糖尿病肾病患者肾组织中的变化及其与糖尿病肾病(DN)临床与病理表现之间的关系.方法以正常肾组织为对照,采用特异性抗体和免疫组织化学染色方法,对30例DN患者肾组织中VEGF和VEGF-R的分布及其强度变化进行了观察,并结合临床及肾脏病理进行了分析.结果DN患者肾小球VEGF和VEGF-R无论在分布上,还是在强度变化上与正常人相比均有明显差异.DN患者肾小球VEGF和VEGF-R表达增加与患者蛋白尿(83.3%vs33.3%,P＜0.01)、糖尿病视网膜病变(66.7%vs16.7%,P＜0.01)关系密切,而与高血压,糖化血红蛋白水平之间无明显相关性.DN患者肾小球VEGF和VEGF-R表达增加还与肾小球内皮细胞损伤所致的一些组织形态学改变,如K-W结节(72.2%vs16.7%,P＜0.05)、肾小球内皮细胞增生(66.7%vs33.3%,P＜0.05)及微血管瘤形成(61.6%vs25.0%,P＜0.05)的发生显著相关.结论DN患者肾组织中VEGF及VEGF-R2的表达增加与DN患者的蛋白尿形成、糖尿病视网膜病变和内皮细胞损伤所致的形态学改变关系密切.VEGF介导了DN患者肾小球内皮细胞损伤和功能紊乱的发生.     

Melatonin ameliorates SGLT2 inhibitor-induced diabetic ketoacidosis by inhibiting lipolysis and hepatic ketogenesis in type 2 diabetic mice

Sodium-glucose cotransporter-2 inhibitors (SGLT2i) are effective hypoglycemic agents that can induce glycosuria. However, there are increasing concerns that they might induce diabetic ketoacidosis. This study investigated the effect of melatonin on SGTL2i-induced ketoacidosis in insulin-deficient type 2 diabetic (T2D) mice. The SGLT2i dapagliflozin reduced blood glucose level and plasma insulin concentrations in T2D mice, but induced increases in the concentrations of plasma β-hydroxybutyrate, acetoacetate, and free fatty acid and a decrease in the concentration of plasma bicarbonate, resulting in ketoacidosis. Melatonin inhibited dapagliflozin-induced ketoacidosis without inducing any change in blood glucose level or plasma insulin concentration. In white adipose tissue, melatonin inhibited lipolysis and downregulated phosphorylation of PKA, HSL, and perilipin-1. In liver tissue, melatonin suppressed cellular cyclic AMP levels and downregulated phosphorylation of PKA, AMPK, and acetyl-CoA carboxylase (ACC). In addition, melatonin increased hepatic ACC activity, but decreased hepatic CPT1a activity and acetyl-CoA content. These effects of melatonin on lipolysis and hepatic ketogenesis were blocked by pretreatment with melatonin receptor antagonist or PKA activator. Collectively, these results suggest that melatonin can ameliorate SGLT2i-induced ketoacidosis by inhibiting lipolysis and hepatic ketogenesis though cyclic AMP/PKA signaling pathways in T2D mice. Thus, melatonin treatment may offer protection against SGLT2i-induced ketoacidosis.     

BCG vaccine prevents insulitis in low dose streptozotocin-induced diabetic mice

Autoimmune type 1 diabetes mellitus is caused by the immunologic destruction of pancreatic beta-cells; therefore, there have been many attempts at immunologic modulation as a block or prevention of the underlying process. The aim of this study is to investigate the effect of BCG vaccination on low dose streptozotocin-induced diabetic (LDSD) mice. The mice were pretreated with BCG 7 days before starting low dose streptozotocin (STZ), observed body weight and blood glucose for 2 months, then analyzed the severity of the STZ-induced insulitis after the animals were sacrificed. In this experiment, the mean body weights in the BCG-STZ group on days 1, 19, 33, 47, and 61 of the experiment were 37.5 +/- 3.6, 37.3 +/- 3.6, 37.5 +/- 3.5, 39.4 +/- 3.9, and 39.3 +/- 4.5 (g), respectively. Those in the STZ group were 37.7 +/- 3.5, 38.3 +/- 4.5, 38.4 +/- 3.9, 36.2 +/- 4.5, and 36.3 +/- 4.0 (g), respectively (P < 0.05). The mean blood glucose levels in the BCG-STZ group on days 1, 19, 33, 47, and 61 were 106.5 +/- 8, 150 +/- 37, 147 +/- 54, 143 +/- 60, and 142 +/- 66 (mg/dl), respectively. Those in the STZ group were 103 +/- 12, 196 +/- 90, 261 +/- 236, 236 +/- 91, and 224 +/- 89 (mg/dl), respectively (P < 0.05). The numbers developing grade 0, I, II, III, and IV insulitis in the BCG-treated group were 63, 48, 33, 4, and 2, respectively, and in the control group were 16, 23, 31, 45, and 35, respectively. This study indicates that BCG vaccination reduces the development of insulitis and overt diabetes in LDSD mice.     

氯沙坦对自发性2型糖尿病KKAy小鼠肾脏损害的保护作用

目的探讨氯沙坦在治疗KKAy小鼠糖尿病早期肾损害中的应用价值。方法将20只雄性8周龄KKAy小鼠随机分为治疗组（n=10）和非治疗组（n=10）,治疗组从8周龄始予以氯沙坦10 mg/（kg.d）饮水喂入,C57BL/6小鼠为正常对照组（n=10）。于20周龄测定各组小鼠血糖、尿微量白蛋白、尿肌酐,并留取肾脏标本,于光镜及电镜下观察其肾脏病理改变。结果氯沙坦治疗对KKAy小鼠体质量及血糖无影响;与非治疗组比较,氯沙坦治疗减少了KKAy小鼠的尿白蛋白/肌酐比率（P〈0.05）,改善了KKAy小鼠的病理损害。结论氯沙坦治疗能减少KKAy小鼠尿白蛋白排泄率,改善肾脏病理损害。     

雷公藤甲素治疗db／db糖尿病小鼠的疗效观察

目的:利用db/db小鼠验证雷公藤甲素对糖尿病肾脏损伤的治疗作用,探讨雷公藤甲素防治糖尿病肾病的机制. 方法:9周龄的db/db和db/m小鼠分为五组:(1)db/m正常对照组;(2)dh/dh糖尿病对照组;(3)缬沙坦治疗纽;(4)雷公藤甲素低剂最治疗组;(5)雷公藤甲素高剂繁治疗组.于4周、8周及12周测定各组24h尿白蛋白、血生化和体重.光镜观察肾小球病变,电镜观察足突改变,并作定量分析.免疫病理观察足细胞裂孔膜蛋白nephrin,足细胞损伤标志物desmin,炎症反应标志物单核细胞趋化蛋白1(MCP-1),氧化应激标志物4羟壬烯醛(4-HNE)的表达. 结果:db/db小鼠经雷公藤甲素治疗后蛋白尿下降,肾小球肥大和足细胞损伤减轻,肾组织炎症和氧化应激状态改善,同时高血脂和肥胖减轻.该作用随治疗时间延长,效果更加明显,且高剂量疗效优于低剂量.雷公藤甲素降低蛋白尿、改善肾小球肥大的作用与缬沙坦相似,但降低肾组织炎症和氧化应激的作用雷公藤甲素比缬沙坦更强. 结论:雷公藤甲索能明显降低dh/db小鼠尿蛋白的排泄,减轻肾组织炎症反应,改善肾脏组织病变,对糖尿病肾脏损伤具有显著且更全面的治疗作用.     

Spontaneous glucose intolerance in the progeny of low dose streptozotocin-induced diabetic mice

Summary Multiple low doses of streptozotocin (LDS) induce low-incidence diabetes mellitus in Balb/cHan and high-incidence diabetes in CD-1 mice. We studied offspring of diabetic parents in both strains. Group 1 consisted of litters from control mice with no streptozotocin treatment. Group 2 litters had an LDS diabetic mother and a control father, group 3 litters had control mother with LDS diabetic father, and group 4 litters had both, LDS diabetic mother and father. Diabetes was induced by 5×40 mg streptozotocin per kg on five consecutive days. Progeny of diabetic mothers showed a state of reduced glucose tolerance associated with reduced glucose disappearance during intravenous glucose tolerance test and increased insulin secretion of isolated islets of Langerhans. These metabolic abnormalities predominated in the male litters of both strains of mice. Amniotic insulin was increased in diabetic mothers during pregnancy. No histologic abnormalities were observed in group 2 progeny. Pancreases in male offspring of LDS diabetic CD-1 fathers (group 3) were studied for insulitis. Insulitis was found in 40% of mice with normal glucose tolerance. A single subdiabetogenic dose of streptozotocin (40 mg/kg) induced insulitis in 90% of pancreases accompanied by reduced insulin release of isolated islets. By contrast, male Balb/cHan progeny of diabetic fathers failed to develop insulitis. In conclusion, we found (1) parental LDS diabetes was transmitted more often to male offspring, (2) maternal LDS diabetes was associated with hyperinsulin secretion and glucose intolerance in the offspring and (3) paternal LDS diabetes was accompanied by insulitis and insulin secretion deficiency in CD-1 progeny.     

Continued smoking exacerbates but cessation ameliorates progression of early type 2 diabetic nephropathy

PURPOSE: We tested the hypothesis that continued cigarette smoking exacerbates and its cessation ameliorates progression of the early nephropathy of type 2 diabetes mellitus (DM2) from microalbuminuria to macroalbuminuria. METHODS: We recruited 91 DM2 subjects with microalbuminuria, 39 nonsmokers and 52 smokers. Smokers underwent smoking cessation intervention with 11 of the 52 smokers quitting, yielding 3 groups: nonsmokers (NS, n = 39), continued smokers (S, n = 41), and quitting smokers (Quit, n = 11), all on angiotensin converting enzyme inhibition (ACEI), treated toward recommended BP and glycemic targets, and followed prospectively for 5 years. Subjects had yearly measurements of estimated glomerular filtration rate (eGFR) and albumin (mg)-to-creatinine (g) ratios (alb/cr) in spot morning urines. Comparison of changes in characteristics was done using analysis of variance, with all pair wise multiple comparison procedure at alpha = 0.05. RESULTS: Although average urine alb/cr was not different among groups at recruitment, 7 of the 41 S (17%) but none of the 50 NS or Quit progressed to macroalbuminuria (P < 0.003). eGFR decline rate was faster in S (-1.79 +/- 0.35 mL/min/yr) than in NS or Quit (-1.30 +/- 0.43 and -1.54 +/- 0.37 mL/min/yr, respectively, P < 0.001). Multivariate analysis revealed smoking to be the only measured baseline factor that influenced eGFR decline rate (P < 0.041). CONCLUSION: Smoking exacerbates progression of early to advanced DM2 nephropathy and its cessation is an effective kidney-protective intervention in the early nephropathy of DM2.     

A renoprotective effect of low dose losartan in patients with type 2 diabetes

It has been reported that angiotensin II receptor blocker (ARB) improves proteinuria in diabetic patients. However, whether this is a direct effect of ARB or through lowering blood pressure is still controversial. The aim of this study is to determine the direct effect of ARB on diabetic nephropathy. Thirty-four type 2 diabetic patients with early kidney damage were divided into two groups: losartan group (n=17) and control group (n=17). In losartan group, low dose (25mg) of losartan was administered once daily for a year. Blood pressure at home, blood pressure at office and urinary albumin/creatinine ratio (UACR) were measured before and during the treatment. After a 1-year observation, the increment of UACR was significantly smaller in losartan group than that in control group [-23.8+/-13.7 mg/gCr vs. 15.9+/-13.2mg/gCr, mean+/-S.E.M., P=0.0114]. Mean blood pressure levels did not change before and during the observation period both in losartan group and control group, though only systolic blood pressure at home decreased slightly but significantly. There were no significant differences in the levels of HbA(1c), fasting plasma glucose, total cholesterol, triglyceride and body mass index between the two groups. The observed decrease in UACR in the losartan-treated group might be attributed to a direct renoprotective action in addition to a subtle decrease in systolic blood pressure at home.     

别嘌醇对2型糖尿病小鼠肾小管间质prohibitin表达与细胞凋亡的影响

目的探讨抑制尿酸药物别嘌醇对2型糖尿病db/db小鼠肾小管上皮细胞prohibitin表达及细胞凋亡的影响。方法将T2DM db/db小鼠随机分为:db/db小鼠对照组(db/db组)、db/db小鼠+别嘌醇50 mg·kg-1·d-1治疗组(db/db+A组);将db/m小鼠作为对照组(db/m组),干预12 w后检测血糖、血尿素氮、血尿酸、血甘油三酯、24 h尿蛋白定量水平;电镜下观察肾小管上皮细胞病理改变;Western印迹及免疫组化法检测肾皮质抗增殖因子(prohibitin)、凋亡诱导因子(AIF)的定位与表达水平;分光光度计检测肾皮质丙二醛(MDA)的含量;原位末端脱氧核糖核酸转移酶介导的脱氧尿苷三磷酸标记法(TUNEL法)检测肾小管间质细胞凋亡情况。结果①12 w末,db/db组小鼠血糖、血尿酸、血甘油三酯、血尿素氮、24 h尿蛋白定量、肾组织匀浆MDA含量较db/m组均有不同程度的升高(P<0.05),而db/db+A组血尿酸、血尿素氮、24 h尿蛋白定量、肾组织MDA含量均较同时期db/db组降低(P<0.05)。②免疫组化与Western印迹检测结果均提示,db/db组肾皮质prohibitin蛋白表达量较db/m组明显降低(P<0.01),db/db+A组表达比db/db组有所增强(P<0.01)。db/db组肾皮质AIF蛋白表达明显高于db/m组(P<0.01),db/db+A组表达比db/db组有所降低(P<0.01)。③电镜下db/db组小鼠肾小管上皮细胞线粒体可见肿胀、空泡变,嵴结构消失等病变,db/db+A组上述病变减轻。④TUNEL检测结果:db/db组小鼠肾小管上皮细胞及间质细胞凋亡数量较db/m组明显增多,db/db+A组肾小管上皮细胞凋亡率较db/db组降低。结论别嘌醇可抑制T2DM小鼠肾小管间质细胞凋亡,其机制可能与其降低血尿酸水平后提高肾组织prohibitin的表达,减少局部氧化应激反应,抑制AIF增多并向核内转位有关。