糖调节受损人群胰岛素抵抗与胰岛β细胞功能的研究

目的　评价糖调节受损(IGR)人群胰岛素抵抗(IR)与胰岛β细胞功能状态。　方法　(1)从青岛地区流行病学调查资料中,选取正常糖耐量(NGT)者447例;IGR 277例,其中空腹血糖受损(IFG)142例;糖耐量受损(IGT)93例;IFG IGT42例。(2)测身高、体重、腰围、血压及血脂,空腹与糖负荷后血糖、胰岛素。(3)评价IR及基础与糖负荷后早期胰岛素分泌功能。　结果　IGR人群的年龄、血压、体质指数(BMI)、腰围、腰臀比均明显高于NGT人群。而IGT组的年龄、甘油三酯高于IFG组。校正年龄、性别及BMI等因素后,IGR人群HOMA-IR增高(P<0.05), IFG、IGT及IFG IGT组间无差异;IFG与IFG IGT组的HOMA-β明显低于NGT和IGT组(P<0.01); IGT组△I30/△G30 低于NGT(P<0.05)。Logistic回归分析显示,年龄、BMI、HOMA IR及HOMA β与IFG的发生密切相关(P<0.01),年龄、BMI、△I30/△G30则与IGT的发生相关(P<0.05)。　结论　IGR人群存在IR,同时IFG基础状态下胰岛β细胞功能轻度受损,而IGT人群的早期胰岛素分泌反应减弱。     

Calpain-10基因SNP43单核苷酸多态性与2型糖尿病的相关性研究

采用错配聚合酶链反应技术,对128例2型糖尿病患者(T2DM组)和102例健康者(对照组)的Cal-pain-10基因SNP43单核苷酸多态性进行基因分型,并测定其体质量指数(BMI)、腰围/臀围、空腹血糖、甘油三酯和胆固醇.结果显示,两组Capain-10基因SNP43等位基因G、A频率无统计学差异(P>0.05);两组Calpain-10基因SNP43多态性中,GG型与GA AA型基因者的上述指标比较均无统计学差异(P均>0.05);对照组基因GA AA型者的甘油三酯较GG型者高(P<0.05).认为Calpain-10基因SNP43单核苷酸多态性可能与T2DM的遗传易感性无相关性.     

社区老年正常糖耐量人群胰岛素抵抗和胰岛β细胞功能研究

入选老年正常糖耐量(NGT)者2 929名、糖耐量受损(IGT)者448例和2型糖尿病(T2DM)患者1143例.NGT者根据空腹血糖(FBG)四分位数和十分位数分别分为4个亚组和10个亚组.结果显示,中国老年NGT人群随着血糖升高,空腹胰岛素和稳态模型评估的胰岛素抵抗指数(HOMA-IR)逐渐升高.以HOMA-IR的75％位点2.15为切割点,≥2.15者在4个NGT亚组、IGT组、T2DM组中的比例逐渐升高;超重或肥胖、高血压和高甘油三酯组HOMA-IR≥2.15比例明显升高;相反,中国老年NGT人群中随着血糖升高,稳态模型评估的胰岛β细胞功能指数(HOMA-β)逐渐下降,以HOMA-β 25％位点41.79为切割点,＜41.79者在4个NGT亚组、IGT组、T2DM组中的比例逐渐升高;非肥胖、正常血压和正常甘油三酯血症患者HOMA-β＜41.79的比例明显升高.logistic回归分析显示年龄和处置指数是影响老年2型糖尿病独立的危险因素.     

糖调节受损者胰岛素抵抗及胰岛β细胞分泌功能

目的探讨糖调节受损各亚组人群胰岛素抵抗(IR)和胰岛β细胞分泌功能。方法选取南京市某社区卫生服务中心健康体检的3640名社区居民,平均年龄(56.7±9.52)岁。通过询问病史,人体测量,检测空腹、口服葡萄糖耐量试验(OGTT)30 min、120 min血糖和胰岛素等,确诊糖调节正常者(NGT)1 698例、空腹血糖受损者(IFG)745例、糖耐量受损者(IGT)551例、联合糖调节受损者(CGI)646例。结果采用多分类Logistic回归分析,调整性别、年龄、体重指数(BMI)后发现,随着HOMA-IR水平的升高或HOMA_%β水平的降低,IFG、CGI发生风险均递增(调整后P均0.001);随着△I30/△G30水平的降低,IGT、IFG、CGI发生风险均递增(调整后P均0.001)。结论 IR增加、胰岛β细胞基础分泌功能降低以及糖负荷后早期相胰岛素分泌不足均与IFG和CGI发生有关;IGT发生主要与糖负荷后早期相胰岛素分泌不足有关。     

高血压病患者动态血压与糖代谢异常相关性的临床研究

目的探讨高血压病患者动态血压变化与糖代谢异常的关系.方法对110例原发性高血压患者行动态血压监测(ABPM)和糖耐量试验(OGTT),根据糖负荷后2h血糖(2hPG)水平分为糖耐量正常(NGT)、糖耐量减低(1GT)和新发现2型糖尿糖(T2DM)三组.对三组间动态血压参数和糖代谢指标进行统计学分析.结果IGT组24h舒张压(24h DBP)、夜间舒张压(nDBP)和24h舒张压负荷低于NGT和T2DM组(P＜005).T2DM组非勺型血压和夜间高血压发生率高,与NGT组比较差异有统计学意义(P＜001);T2DM组胰岛素低抗指数(IRI)、体质指数(BMI)显著高于NGT和IGT组(P＜005).Logistictic回归分析显示:脉压增大与餐后血糖显著相关,非勺型血压与胰岛素抵抗(IR)显著相关.结论IGT患者的DBP降低,脉压增大与餐后血糖水平相关.T2DM患者的血压昼夜节律紊乱与IR的程度密切相关.     

不同糖耐量人群血浆脂肪酸谱与胰岛素抵抗

目的　研究不同糖耐量人群血浆脂肪酸谱与胰岛素抵抗 (IR)之间的关系。方法　将受试者根据口服葡萄糖耐量试验 (OGTT)结果分为正常糖耐量组 (NGT) ,糖耐量受损组 (IGT )及 2型糖尿病组(DM )。采用毛细血管气相色谱法测定血浆脂肪酸谱 ,用胰岛素敏感指数 (IAI)评估IR。结果　DM组及IGT组血浆软脂酸 (C16:0 )、硬脂酸 (C18:0 )、二十二烷酸 (C2 2 :0 )、二十四烷酸 (C2 4:0 )和饱和脂肪酸浓度较NGT组明显升高 (P <0 .0 5～P <0 .0 1) ;花生四烯酸 (C2 0 :4)分别从NGT、IGT和DM组依次升高 ,差异有显著性 (P <0 .0 5～P <0 .0 1) ;血浆饱和脂肪酸 (SFA)从NGT、IGT、DM亚组依次升高 (P <0 .0 5～P <0 .0 1) ;NGT组的多不饱和脂肪酸 (PUFA)与饱和脂肪酸 (SFA)的比率高于IGT组和DM组 (均P <0 .0 5 ) ;血浆C16:0、C2 0 :4、C2 2 :0、SFA与IAI呈负相关 (P均 <0 .0 1)、PUFA/SFA与IAI呈正相关 (P <0 .0 1)。结论　不同糖耐量者血浆脂肪酸谱不同 ,糖耐量减低与 2型糖尿病患者SFA浓度升高 ,PUFA/SFA下降 ,且与胰岛素抵抗密切相关     

不同糖耐量及肥胖人群中血浆apelin水平及相关因素分析

目的 评价肥胖、不同糖耐量人群中血浆apelin(APJ endogenous ligand)水平,探讨apelin与BMI、血脂、血糖等的相关性. 方法 根据糖耐量试验结果,将120例观察对象分为糖耐最正常(NGT)组、糖耐量受损(IGT))组和新诊断2型糖尿病(T2DM)组.上述三组又按BMI再各自分为正常体重(NW,BMI<25kg/m~2)与超重/肥胖(OW/Ob,BMI≥25kg/m~2)亚组,比较上述三组及各亚组之间血浆中空腹及服用75克葡萄糖后2h apelin的水平,同时检测血糖及血脂,计算BMI. 结果三组空腹及糖负荷后2h apelin差异均有统计学意义(P<0.05或P<0.01),且IGT组和T2DM组的OW/Ob亚组患者apelin水平均高于NGT的OW/Ob亚组.BMI、FPG和SBP是血浆apelin的独立影响因素(P<0.05或P<0.01). 结论 血浆apelin水平与Ob及T2DM有关.     

不同糖耐量个体血清瘦素水平与特异胰岛素、胰岛素原及胰岛素敏感性的关系探讨

目的　研究不同糖耐量人群空腹瘦素水平与特异胰岛素、胰岛素原及胰岛素敏感性之间的关系。方法　用放射免疫法测量 5 4例正常糖耐量 (NGT)、33例糖耐量低减 (IGT)、4 7例新发 2型糖尿病 (DM )的空腹瘦素水平、口服葡萄糖耐量试验 (OGTT) 0、1/2、1、2h的特异胰岛素 (SI)和胰岛素原 (PI)。结果　 (1)多元逐步回归分析显示 ,性别、体重指数 (BMI)、胰岛素敏感性指数是影响空腹瘦素水平最重要的因素 (校正的R2 分别为 0 .2 5 1、0 .4 19、0 .4 38,P值分别为 <0 .0 0 1、<0 .0 0 1、<0 .0 5 ) ;空腹血清瘦素水平与OGTT各时间点PI、SI、PI/SI值无相关性。 (2 )在校正性别、BMI等影响因素后 ,空腹血清瘦素水平在不同糖耐量组差异无显著性 ;DM组OGTT各时间点PI/SI值明显高于IGT组和NGT组 (P <0 .0 1) ;胰岛素敏感性 (ISI)为NGT组 >IGT组 >DM组 (P <0 .0 0 1)。结论　在测定特异胰岛素、胰岛素原时 ,血清瘦素水平除了与性别、BMI相关外 ,尚与胰岛素敏感性 (按SI水平计算 )相关 ;不同糖耐量状态对血清瘦素水平无明显影响 ;DM组存在胰岛素不敏感、PI/SI失调     

糖调节受损人群胰岛素抵抗与胰岛β细胞功能的关系

将142例健康查体者分为正常糖耐量（NGT）组、单纯空腹血糖受损（IFG）组、单纯糖耐量受损（IGT）组、IFG＋IGT组和新诊断的2型糖尿病（T2DM）组共5组,评价各组胰岛素抵抗、基础状态下及糖负荷后的胰岛素分泌功能。结果糖调节受损人群存在基础和糖负荷后胰岛β细胞分泌功能受损及显著的胰岛素抵抗,且IFG和IGT人群有不同的病理生理特征。认为应针对IFG和IGT的不同特点给予相应的早期干预。     

糖耐量受损者胰岛素敏感性及胰岛β细胞功能的研究

目的 研究糖耐量受损(IGT)者的胰岛素抵抗(IR)及胰岛β细胞功能变化。方法 选取正常糖耐量(NGT)、IGT、2型糖尿病(T2DM)者共34例，以高胰岛素正血糖钳夹技术测定IR，行静脉葡萄糖耐量试验评估胰岛β细胞分泌功能。结果 与NGT组相比，IGT组、T2DM组的IR显著升高；IGT组胰岛素第一时相分泌明显下降，空腹胰岛素(FIns)水平及第二时相分泌水平升高；T2DM组IR与IGT组处于同一水平，FIns较NGT组显著减少。结论 由NGT向IGT的演变过程中，IR和胰岛素分泌缺陷共同起作用。     

Clinical utility of insulin and insulin analogs

Diabetes is a pandemic disease characterized by autoimmune, genetic and metabolic abnormalities. While insulin deficiency manifested as hyperglycemia is a common sequel of both Type-1 and Type-2 diabetes (T1DM and T2DM), it does not result from a single genetic defect—rather insulin deficiency results from the functional loss of pancreatic β cells due to multifactorial mechanisms. Since pancreatic β cells of patients with T1DM are destroyed by autoimmune reaction, these patients require daily insulin injections. Insulin resistance followed by β cell dysfunction and β cell loss is the characteristics of T2DM. Therefore, most patients with T2DM will require insulin treatment due to eventual loss of insulin secretion. Despite the evidence of early insulin treatment lowering macrovascular (coronary artery disease, peripheral arterial disease and stroke) and microvascular (diabetic nephropathy, neuropathy and retinopathy) complications of T2DM, controversy exists among physicians on how to initiate and intensify insulin therapy. The slow acting nature of regular human insulin makes its use ineffective in counteracting postprandial hyperglycemia. Instead, recombinant insulin analogs have been generated with a variable degree of specificity and action. Due to the metabolic variability among individuals, optimum blood glucose management is a formidable task to accomplish despite the presence of novel insulin analogs. In this article, we present a recent update on insulin analog structure and function with an overview of the evidence on the various insulin regimens clinically used to treat diabetes.     

Treatment of insulin lipoatrophy with monocomponent insulin

Summary A female diabetic with severe insulininduced lipoatrophy was successfully treated with a monocomponent (MC) Lente preparation. This patient was studied for over 6 years and, during periods of treatment with various insulins of different purity, a variety of reactions was observed in the adipose tissue. Evidence is presented that lipoatrophy may be caused by insulin impurities. Lipoatrophy occurring after treatment with recrystallized, mixed species Lente insulin was substantially reduced after treatment with 10 times recrystallized porcine Lente, but recurred on 4 times recrystallized beef Lente, also in areas where beef Lente was not injected. Beef insulin impurities seem more prone to produce lipoatrophy than pork insulin impurities. It is suggested that MC-insulin is the treatment of choice for this condition.     

Mechanism of action of insulin and insulin analogues

Summary A [¹⁴C]-glucose tracer infusion method was used to compare the effects of insulin infusion on glucose metabolism with the effects of infusion of three semisynthetic modified insulins and of proinsulin. Insulin produced hypoglycaemia in the anaesthetised dog by decreasing hepatic glucose production and increasing peripheral glucose utilisation. Compensatory antihypoglycaemic mechanisms eventually modified these responses. A₁ B₂₉-Diacetyl insulin exerted an hypoglycaemic effect entirely by stimulation of peripheral glucose uptake. A₁-B₂₉ crosslinked insulins and proinsulin produced hypoglycaemia almost entirely by decreasing hepatic glucose production and had little effect on tissue uptake. These observations suggest that insulin analogues may have actions in vivo that are qualitatively different from those of native insulin and suggest that certain analogues have a predominant action on the liver. This has important therapeutic implications concerning the development of semisynthetic insulins for clinical use.     

Measurement of insulin absorption and insulin action

For the practical implementation of every type of insulin therapy it is necessary to know both the time course of action of therapeutically used short- and long-acting insulin preparations and the factors influencing such time-action profiles. The only reliable way to obtain the required quantitative information about the pharmacokinetic and glucodynamic properties of insulin preparations has been the use of the euglycemic glucose clamp technique. The first studies with each new insulin formulation or insulin application technique should be performed with healthy subjects in order to have the most comparable study conditions. Thereafter, results from such clinical-experimental studies should be verified in similar studies with patients with diabetes. Earlier investigational approaches, which either had been limited to the determination of the pharmacokinetic properties of insulin preparations or had used the quantitative decrease of the blood glucose level as a measure of the pharmacodynamic properties, do not provide valid quantitative results. The proposed glucose clamp technique makes possible the quantitative study of the pharmacokinetic and pharmacodynamic properties of insulin preparations under comparative and reproducible conditions.     

Variability of insulin absorption and insulin action

Subcutaneous (s.c.) injections of identical insulin doses may lead to considerable intra- and inter-individual differences in the current metabolic control of patients with diabetes mellitus. This well-known variability of the metabolic effect of insulin hampers practical insulin therapy considerably. The aim of this review is to summarize the knowledge about this topic, with a special focus on the variability of insulin action after pulmonary administration of insulin. A number of studies have been published describing the variability of insulin absorption from the s.c. depot. Only in a few published studies has the variability of insulin action after s.c. administration been quantified. Under controlled experimental conditions s.c. injections of regular insulins result in an intra-individual coefficient of variation (CV) of 15-25% of certain pharmacodynamic summary measures--which characterize the metabolic effect of the applied insulin--in healthy subjects. The inter-individual variability was approximately 10% higher than the intra-individual variability. Subcutaneously injected intermediate- and long-acting insulin preparations were described to have an even greater variability (> 50%) than subcutaneously injected regular insulin. However, in a glucose clamp study s.c. application of NPH insulin led to an intra-individual CV in the range of 12-45% in healthy subjects. The reason for this discrepancy might be that the NPH insulin suspension was sufficiently shaken prior to drawing up the dose. Compared with conventional insulin formulations, rapid- and long-acting insulin analogues appear to have a similar variability, which means that, unfortunately, no considerable advantages in terms of variability were achieved by the invention of these novel insulin preparations. There are no appropriate studies available investigating the variability of the metabolic effect after s.c. insulin administration in patients with diabetes. The inhalation of insulin is a novel form of insulin administration that is currently under clinical development. The variability of the metabolic effect induced by the inhalation of insulin has up to now only been investigated in a small number of (published) studies. In a glucose-clamp study with healthy subjects the inhalation of an identical insulin dose on three study days led to an intra-individual variability that was comparable to that after s.c. injection of regular insulin. In a dose-response study with patients with type 1 diabetes the intra-individual CV was 34% for the area under the curve of the glucose infusion rate for 0-10 h. Studies with patients with type 2 diabetes have shown that the intra-individual CVs were within the range seen after s.c. insulin administration or even lower. In summary, the intra-individual variability of the metabolic effect observed after insulin application, be it subcutaneously injected or be it inhaled, is considerable and, therefore, hampers practical diabetes therapy. To date no means have been found that could lead to a clinically relevant reduction in the variable metabolic effect.