Impact of glucagon response on postprandial hyperglycemia in men with impaired glucose tolerance and type 2 diabetes mellitus

Glucagon is the physiological antagonist of insulin. Postprandial (pp) hyperglycemia in impaired glucose tolerance (IGT) and in type 2 diabetes mellitus (T2DM) may also depend on irregularities in glucagon secretion. This study investigated the glucagon excursion after a lipid-glucose-protein tolerance test in subjects with different stages of glucose intolerance. We also analyzed the relationship between pp glucagon secretion and hyperglycemias. A total of 64 men (27 healthy subjects with normal glucose tolerance [NGT], 15 with IGT, and 22 with T2DM) were examined. Plasma glucose (PG), insulin, proinsulin, free fatty acids, and triglycerides were measured in the fasting state and at 30 minutes and 2, 3, 4, and 6 hours after the intake of the test meal, which contained 126 g carbohydrates, 92 g fat, and 17 g protein. Postprandial concentrations of metabolic parameters were calculated as area under the curve (AUC). Glucagon was measured in the fasting state and at 30 minutes and 2 and 4 hours pp. Early glucagon increment was defined as glucagon at 30 minutes minus fasting glucagon. The insulin response was quantified as insulin increment divided by PG increment in the corresponding time. Insulin resistance was calculated using lomeostasis model assessment (HOMA). Fasting glucagon was significantly increased in IGT vs NGT (P<.05), and early glucagon increment was significantly higher in T2DM vs NGT and IGT (P<.05). The 2-hour glucagon concentration after the load (AUC) was increased in IGT and T2DM vs NGT (P<.05). Early glucagon increment and the 2-hour AUC of glucagon were strongly correlated to pp glycemia (r=0.494 and P=.001, and r=0.439 and P=.003, respectively). An inverse correlation was observed between early glucagon increment and insulin response at 30 minutes and 2 hours after the meal load (r=-0.287 and P=.026, and r=-0.435 and P=.001, respectively). The 2-hour AUC of glucagon was significantly associated with insulin resistance (r=0.354, P=.020). Multivariate analysis revealed 2-hour insulin response and early glucagon increment as significant independent determinants of the AUC of PG in IGT (R=0.787). In T2DM, 2-hour insulin response, insulin resistance, and early glucagon increment were significant determinants of the AUC of PG (R=0.867). Our study suggests an important role for the irregularities in glucagon response in the pp glucose excursion after a standardized oral mixed meal in IGT and in T2DM. According to our data, a bihormonal imbalance starts before diabetes is diagnosed. Prospective studies are needed to evaluate the impact of glucagon on the progression of glucose intolerance and the possible effects of medicinal suppression of glucagon increment to prevent the progression of glucose tolerance.     

不同血糖状态下血清超敏C反应蛋白、纤溶酶原激活物抑制物-1水平的变化及与胰岛素抵抗的关系

目的检测不同血糖状态人群空腹血清超敏C反应蛋白（hs—CRP）、纤溶酶原激活物抑制物-1（PAI-1）水平,探讨hs—CRP、PAI-1与胰岛素抵抗之间的关系。方法选取健康对照组、糖耐量减低组、2型糖尿病组受试者各30例,测定受试者空腹血清hs—CRP、PAI-1、血脂、空腹胰岛素等项目,应用稳态模型评估法评价胰岛素抵抗。结果2型糖尿病组、糖耐量减低组、对照组依次比较,hs—CRP、PAI-1、胰岛素抵抗指数均有显著升高（P均〈0．05）;多元逐步回归分析显示体重指数、hs—CRP、PAI-1是影响胰岛素抵抗的重要危险因素。结论2型糖尿病人群、糖耐量减低人群存在明显的胰岛素抵抗,hs—CRP、PAI-1、BMI是加重胰岛素抵抗的危险因素;糖调节受损时期即可能存在慢性炎症反应,并出现大血管病变的一些病理生理改变。     

Tumor necrosis factor alpha and insulin resistance in obese type 2 diabetic patients

The relationship between basal serum tumor necrosis factor alpha (TNFalpha) levels and peripheral tissue (muscle) sensitivity to insulin was examined in 63 subjects with normal glucose tolerance (NGT), 18 subjects with impaired glucose tolerance (IGT), and 123 patients with type 2 diabetes mellitus (T2DM). The BMI was similar in NGT (28.8+/-0.7 kg/m(2)), IGT (31.1+/-1.0), and T2DM (30.0+/-0.4) groups. The fasting serum TNFalpha concentration in T2DM (4.4+/-0.2 pg/ml) was significantly higher than in NGT (3.1+/-0.2) and IGT (3.4+/-0.2; both P<0.05). In T2DM the fasting plasma glucose (FPG=183+/-5 mg/dl) and insulin (FPI=17+/-1 micro U/ml) concentrations were significantly higher than in NGT (FPG=95+/-1; FPI=10+/-1) and IGT (FPG=100+/-2; FPI=13+/-1; all P<0.01). The rate of total body insulin-mediated glucose disposal (Rd; 40 mU/m(2) min euglycemic insulin clamp in combination with (3)H-glucose) was reduced in T2DM (102+/-3 mg/m(2) min) compared with NGT (177+/-10) and IGT (151+/-14; both P<0.01). The serum TNFalpha concentration was inversely correlated with Rd (r=-0.47, P<0.0001) and positively correlated with both FPG (r=0.32, P=0.004) and FPI (r=0.32, P=0.004) in NGT plus IGT. No correlation was observed between serum TNFalpha and Rd (r=-0.02), FPG (r=0.15), or FPI (r=0.15) in T2DM. In stepwise multiple regression analysis using age, sex, BMI, FPG, FPI and serum TNFalpha concentration as independent variables, only BMI and serum TNFalpha concentration were significant and independent predictors of Rd (r(2)=0.29, P<0.0001) in the NGT plus IGT group, while FPG and FPI were significant and independent predictors of Rd (r(2)=0.13, P<0.0001) in T2DM. These results suggest that: (i) an increase in circulating TNFalpha concentration is associated with peripheral insulin resistance and increased plasma glucose and insulin levels prior to the onset of type 2 diabetes; and (ii) the further deterioration in peripheral insulin resistance in T2DM (compared with NGT and IGT) is unrelated to the increase in serum TNFalpha concentration.     

高血压患者胰岛素抵抗与纤溶系统的关系

目的　研究高血压病 (EH)患者胰岛素抵抗 (IR)与纤溶系统的关系。方法　EH病人 71例 ,采用 75g葡萄糖口服负荷法 (OGTT) ,将EH患者分为糖耐量正常组 (NGT) 44例和糖耐量异常组 (IGT) 2 7例 ,正常对照组 3 1例。测定血浆组织型纤溶酶原激活物活性 (t PA)、纤溶酶原激活物抑制物 -1活性 (PAI 1)、纤溶酶原活性 (PLG) ,在OGTT测定的同时作血胰岛素 (INS)测定 ,并根据Cederholm公式计算出胰岛素敏感指数 (ISIc)。结果　NGT组和IGI组相比t PA无明显差别 (P >0 0 5) ,但两组均较正常对照组降低 (P <0 0 5)。NGT组和IGT组PAI -1与正常对照组比较均无明显差别 (P >0 0 5)。IGT与NGT相比PLG增高 (P <0 0 5) ,与正常对照比较PLG明显增高 (P <0 0 1)。ISIc在NGT组和IGT组较正常对照组明显降低 (P <0 0 5,P <0 0 1) ,且IGT组较NGT组更低 (P <0 0 1)。ISIc与t PA ,PAI 1不相关。结论　高血压病人存在胰岛素抵抗 ,当高血压病合并IGT时 ,胰岛素抵抗更明显。EH病人存在纤溶活性的下降 ,当合并IGT时 ,纤溶活性的降低更为明显。t PA和PAI 1与ISIc无明显相关性     

Fibrinolytic dysfunction after gestation is associated to components of insulin resistance and early type 2 diabetes in latino women with previous gestational diabetes

Among patients with metabolic syndrome (MS), atherosclerosis and abnormal fibrinolytic function are frequently present, mostly owing to an increase in plasminogen activator inhibitor-1(PAI-1). We analyze PAI-1 in pregnant women, both normal and with gestational diabetes (GDM) and postpartum regarding its correlation to MS surrogates. Clinical characteristics, glucose tolerance (100g-OGTT), lipids, PAI-1 antigen, insulin sensitivity (HOMA-S), and pancreatic beta-cell function (HOMA-B) were investigated in 34 women. Eleven had normal glucose tolerance (NGT) during pregnancy and 23 had GDM (all GAD antibodies-negative). All patients were studied at 28-34 weeks of gestation and 16-24 weeks after delivery (75 g-OGTT). Parameters of interest were determined using commercial test systems. During pregnancy, PAI-1 was not statistically different between NGT and GDM (47+/-25 ng/ml versus 47+/-28 ng/ml, p=0.9). After gestation, 19 (56%) women had NGT (11 of them from previous NGT group) and 15 (44%) had impaired glucose tolerance (IGT) or DM. The IGT (IGT+DM) group had higher PAI-1 (p=0.01), which did not decreased after delivery NGT-NGT before and after delivery (47+/-25 ng/ml versus 6+/-5 ng/ml; p<0.001), GDM-NGT (62+/-36 ng/ml versus 14+/-15 ng/ml; p=0.001) and GDM-IGT (39+/-20 ng/ml versus 27+/-23 ng/ml; p=0.15). PAI-1 levels were positively correlated (p<0.05) to total cholesterol (r(s)=0.37), triglycerides (r(s)=0.48), fasting plasma glucose (r(s)=0.52), 2-h plasma glucose in the OGTT (r(s)=0.58) and were negatively correlated (p<0.05) with HOMA-S (r(s)=-0.42) and HOMA-B (r(s)=-0.38). Fibrinolytic dysfunction is still present in GDM women and is associated with early development of IGT or T2DM. PAI correlated with surrogate markers of MS levels and may identify a group of women at risk for macroangiopathy.     

2型糖尿病纤溶系统变化与胰岛素抵抗的关系

目的探讨2型糖尿病患者纤溶活性变化与胰岛素抵抗之间的关系。方法采用酶联免疫吸附法测定63例2型糖尿病患者（包括无血管并发症组30例和有血管并发症组33例）和25例正常对照者血浆组织型纤溶酶原激活剂（t-PA）、纤溶酶原激活物抑制剂-1（PAI-1）含量,结合临床资料分析其变化趋势及影响因素。结果2型糖尿病患者血浆t-PA含量明显降低（P〈0．01）,而PAI-1含量明显升高（P〈0．01）,合并血管病变者,此变化更为显著（均P〈0．001）。多元逐步回归分析显示,HOMA模型胰岛素抵抗指数（HOMA—IR）是PAI-1升高的独立危险因素。结论2型糖尿病患者纤溶活性降低,胰岛素抵抗在降低其纤溶活性,并发血管病变中起了重要作用。     

高血糖合并冠心病患者血管性假性血友病因子、纤溶酶原激活剂抑制物及脂联素水平研究

目的探讨高血糖合并冠心病患者血管性假性血友病因子（vWF）、纤溶酶原激活剂抑制物1（PAI-1）及脂联素水平及其意义。方法163例明确诊断冠心病患者,行口服75g葡萄糖耐量试验确诊冠心病合并2型糖尿病44例（26．99％）,冠心病合并单纯糖耐量低减59例（24．38％）,冠心病合并单纯空腹血糖受损15例（7．46％）,冠心病正常糖代谢40例（24．54％）。应用酶联免疫吸附法检测糖尿病组、糖耐量低减组、空腹血糖受损组及正常糖耐量组的vWF、PAI-1及脂联素水平。结果糖尿病合并冠心病组、糖耐量低减合并冠心病组vWF均明显高于正常血糖组,具有显著统计学意义。糖尿病合并冠心病组PAI-1较正常血糖组明显增高,具有统计学意义,而糖耐量低减组及空腹血糖受损组与正常血糖组无明显差异。糖尿病及糖耐量低减组脂联素较正常血糖组明显降低,具有统计学意义,空腹血糖受损组和正常血糖组未见明显差异。结论高血糖合并冠心病患者血管内皮损伤较血糖正常冠心病患者更加明显,及早发现并积极控制血糖对于防止冠心病的发生发展具有重要意义。     

2型糖尿病患者血管紧张素Ⅱ与胰岛β细胞分泌功能的关系探讨

目的 探讨不同糖耐量状态下血管紧张素Ⅱ与胰岛β细胞分泌功能的关系.方法 新诊断2型糖尿病患者42例(DM组)、空腹血糖受损/糖耐量受损者38例(IFG/IGT组)、正常对照者40名(NGT组)行静脉葡萄糖耐量试验,ELISA法测定空腹血管紧张素Ⅱ(AngⅡ)及脂联素水平.计算急性胰岛素分泌反应(AIR3-10)、第一时相(0～10min)胰岛素分泌曲线下面积(AUCⅠ)及峰值浓度、第二时相(10～120min)胰岛素分泌曲线下面积(AUCⅡ)、稳态模型评估胰岛β细胞功能指数(HOMA-β)及胰岛素抵抗指数(HOMA-IR).探讨AngⅡ与AIR3-10、AUCⅠ及峰值浓度、AUCⅡ、脂联素、HOMA-β及HOMA-IR的关系.结果 (1)DM组和IFG/IGT组AngⅡ显著高于NGT组(P＜0.05);DM组和IFG/IGT组AIR3-10、AUCⅠ及峰值浓度、AUCⅡ、脂联素显著低于NGT组(P＜0.05),DM组降低更为显著;(2)AngⅡ与AIR3-10、AUCⅠ及峰值浓度、AUCⅡ、脂联素、HOMA-β呈显著负相关(P＜0.01),与空腹血糖、糖负荷后2 h血糖、空腹胰岛素、HOMA-IR呈正相关(P＜0.05);(3)多元逐步回归分析,AngⅡ与AUCⅠ、AUCⅡ独立相关.结论 AngⅡ为胰岛β细胞分泌功能的独立影响因素.排除血压、体位、药物等因素的影响,高AngⅡ水平可预测2型糖尿病患者胰岛β细胞功能受损及胰岛素抵抗.

Abstract：

Objective To investigate the relationship between angiotensin Ⅱ and pancreatic islet β cell secretion function under different glucose tolerance statuses. Method Forty-two patients with newly diagnosed type 2diabetes mellitus ( DM group), 38 subjects with impaired fasting glucose/impaired glucose tolerance ( IFG/IGTgroup) ,and 40 normal control subjects (NGT group) underwent intravenous glucose tolerance test. Fasting plasma angiotensin Ⅱ ( Ang Ⅱ ) and adiponectin were assayed by ELISA. Acute insulin response from 3 to 10 min( AIR3-10 ),the area under the curve( AUCⅠ ) and the peak concentration of the first-phase ( 0-10 min) insulin secretion, the area under the curve of the second-phase( 10-120 min) insulin secretion( AUCⅡ), homeostasis model assessment for β cell function index(HOMA-β) and homeostasis model assessment for insulin resistance index(HOMA-IR) were calculated to explore the relationship with Ang Ⅱ. Result ( 1 ) The levels of Ang Ⅱ in DM group and IFG/IGT group were significantly higher than that in NGT group( P＜0.05 ). The AIR3-10, AUCⅠ and peak concentration, AUCⅡ ,adiponectin in DM group and IFG/IGT group were significantly lower than those in the NGT group ( P＜0. 05), and these results were more significantly reduced in DM group compared with those in IFG/IGT group. (2) Ang Ⅱ was negatively correlated with AIR3-10, AUCⅠ and the peak concentration, AUCⅡ, adiponectin, HOMA-β ( P＜0. 01 ), and positively correlated with fasting blood glucose,2 h blood glucose after glucose loading, fasting insulin, HOMA-IR (P＜0. 05 ). (3)Multiple stepwise regression analysis showed that Ang Ⅱ was independently associated with AUCⅠ and AUCⅡ.Conclusion Ang Ⅱ was an independent factor that affected the insulin secretion function of pancreatic islet βcells. Ruling out the effect of blood pressure, body position, drugs, and other factors, high levels of Ang Ⅱ could predict the dysfunction of pancreatic islet β cell as well as insulin resistance in patients with type 2 diabetes.     

不同糖耐量水平人群血清真胰岛素和胰岛素原水平的临床意义

目的 探讨不同糖耐量者血清真胰岛素（ＴＩ）及胰岛素原（ＰＩ）水平的变化及临床意义。方法 用特异的单克隆抗体夹心放大酶联免疫分析法（ＢＡ－ＥＬＩＳＡ）检测１３５例正常糖耐量（ＮＧＴ）、８６例糖耐量低减（ＩＧＴ）及１０１例Ⅱ型糖尿病（ＤＭ）者口服葡萄糖耐量试验（ＯＧＴＴ）各点血清ＴＩ及ＰＩ水平。结果 ３组血清空腹ＴＩ差异无显著性（Ｐ〉０．０５）,免疫反应胰岛素（ＩＲＩ）Ⅱ型ＤＭ组明显升高（Ｐ〈０．０１     

A metabolic syndrome independent association between overweight, fibrinolysis impairment and low-grade inflammation in young women with venous thromboembolism.

It is known that overweight induces fibrinolysis impairment. Since this association has not been completely explored in patients with venous thromboembolism (VTE), we aimed to investigate its presence in young women with VTE and, if present, to determine its extent and the factors that influence it. Thirty women aged 23-49 years in the stable period after VTE were included [19 overweight (body mass index > or = 25) and 11 normal weight]; 52 healthy women (27 overweight and 25 normal weight) served as controls. The euglobulin clot lysis time (ECLT), plasminogen, D-dimer, tissue-type plasminogen activator (t-PA) and plasminogen activator inhibitor-1 (PAI-1) antigen and activity, lipids, fasting plasma glucose, insulin, fibrinogen, interleukin-6 and sedimentation rate were compared between the groups. Overweight patients had more impaired fibrinolysis (delayed ECLT, higher PAI-1 and t-PA antigen) than overweight controls (and normal weight patients). There was no difference in levels of insulin, glucose, fibrinogen and interleukin-6, whereas the sedimentation rate was significantly elevated in overweight patients compared with overweight controls [16 (8-31) versus 8 (5-12), P < 0.05]. The sedimentation rate in overweight patients significantly correlated with body mass index, ECLT, t-PA and PAI-1 antigen, but not with fibrinogen or interleukin-6. We found that overweight VTE patients have more prominent fibrinolysis impairment than predictable from parameters of metabolic syndrome and that is associated with an elevated sedimentation rate. This association could represent a new thrombotic risk profile in overweight women.     

Low-density lipoprotein particle size is inversely related to plasminogen activator inhibitor-1 levels. The Insulin Resistance Atherosclerosis Study

High levels of plasminogen activator inhibitor-1 (PAI-1) and preponderance of small dense low-density lipoproteins (LDL) have both been associated with atherosclerotic disease and with the insulin resistance syndrome (IRS). In vitro studies have shown a stimulatory effect of various lipoproteins on PAI-1 release from different cells, including endothelial cells and adipocytes. The authors sought to investigate the relation of PAI-1 to LDL particle size in a large tri-ethnic population (n=1549) across different states of glucose tolerance. LDL size was determined by gradient gel electrophoresis, and PAI-1 was measured by a 2-site immunoassay, sensitive to free PAI-1. PAI-1 was inversely related to LDL size in the overall population (r=-0.21, P<0.0001), independent of gender and ethnicity. However, the authors found a significant interaction with glucose tolerance status (P=0.035). In univariate analysis, the association between PAI-1 and LDL size was most pronounced in subjects with normal glucose tolerance (NGT, r=-0.22, P<0.0001) and weaker in impaired glucose tolerance (IGT, r=-0.12, P=0.03) and type-2 diabetes (r=-0.10, P=0.02). After adjustment for demographic variables and metabolic variables known to influence PAI-1 levels (triglyceride and insulin sensitivity), a significant inverse relation of LDL size to PAI-1 levels was only present in NGT (P=0. 023). In subjects with IGT or overt diabetes, who usually have elevated PAI-1 levels, additional factors other than LDL size seem to contribute more importantly to PAI-1 levels. The demonstrated inverse relation of LDL size and PAI-1 levels provides one possible explanation for the atherogeneity of small dense LDL particles.     

高血压患者胰岛素抵抗与凝血系统功能的关系

目的:研究高血压(EH)患者胰岛素抵抗(IR)与凝血系统功能的关系。方法:按75g葡萄糖口服负荷法(OGTT)结果,69例EH患者被分为糖耐量正常(NGT)组(43例)例和糖耐量异常(IGT)组(26例)。另正常对照组31例。测定各组纤维蛋白原(Pg)、纤溶酶原激活物抑制因子(PAI-1)含量,同时作血胰岛素(INS)测定, 用HOMA指数作为胰岛素抵抗指标。结果:高血压两组与正常对照组相比HOMA指数、Fg、PAI-1水平明显异常(P<0.05～<0.01).高血压IGT组的这些指标较高血压NGT组更恶化(P<0.05～<0.01)。HOMA与PAI-1、Fg 之间具有正相关性,其r分别为0.635,0.832。结论:高血压病人存在胰岛素抵抗和凝血异常,当高血压合并IGT时, 胰岛素抵抗更严重,血液促凝血状态加重。     

Hyperglycaemic siblings of Type II (non-insulin-dependent) diabetic patients have increased PAI-1, central obesity and insulin resistance compared with their paired normoglycaemic sibling

AIMS/HYPOTHESIS: First-degree relatives of Type II (non-insulin-dependent) diabetic patients in cross-sectional studies have increased insulin resistance, associated cardiovascular risk factors and abnormalities of fibrinolysis and coagulation. To minimise between-family genetic and environmental confounders, we investigated within-family relationships between early hyperglycaemia and risk factors. METHODS: Thirteen age and gender matched sibling pairs of Type II (non-insulin-dependent) diabetic patients, one hyperglycaemic, one normoglycaemic (fasting plasma glucose at screening 6.0-7.7 mmol.l(-1) and < 6.0 mmol.l(-1), respectively) were assessed for plasminogen activator inhibitor antigen (PAI-1), tissue plasminogen activator antigen (t-PA), fibrinogen, Factor VII and Factor VIII/von Willebrand factor antigen. Fasting lipid profiles, blood pressure and HOMA insulin sensitivity (%S) were also measured in siblings and in matched subjects without family history of diabetes. RESULTS: Hyperglycaemic and normoglycaemic siblings (7 female, 6 male) were aged, mean (SD) 56.8 (8.7) and 55.8 (8.4) years. Hyperglycaemic siblings had increased PAI-1 antigen, geometric mean (i.q.r.): 26.3 (15.1-45.6) vs 11.1 (2.1-23.3) ng/ml, p=0.0002, similar t-PA antigen, mean (SD) 9.5 (4.3) vs 7.4 (2.5) ng/ml, p=0.2 and fibrinogen 2.2 (0.3) vs 2.3 (0.6) g/l, p=0.5, and reduced %S 66.3 (30.5) vs 82.9 (25), p=0.04. PAI-1 correlated negatively with %S ( r=-0.55, p=0.005). No significant differences were found in blood pressure or fasting lipids. CONCLUSION/INTERPRETATION: A minor increase in plasma glucose in non-diabetic sibling pairs of Type II (non-insulin-dependent) diabetic patients was associated with reduced insulin sensitivity, increased central adiposity and a doubling of PAI-1 antigen concentration, suggesting impaired fibrinolysis. It is possible that this could contribute to increased cardiovascular risk in these subjects.     

The effects of rosiglitazone treatment on the fibrinolytic system in patients with type 2 diabetes mellitus.

Patients with type 2 diabetes mellitus (DM) are at risk for the development of cardiovascular diseases, which can in part be explained by disturbances in the hemostatic and fibrinolytic systems. The effects of rosiglitazone treatment on the fibrinolytic system and insulin sensitivity in patients with type 2 DM were assessed. Twenty-four patients with type 2 DM and 28 healthy subjects were enrolled in the study. Plasma global fibrinolytic capacity (GFC), tissue plasminogen activator (t-PA), and plasminogen activator inhibitor-1 (PAI-1) levels were measured. Insulin resistance was calculated by hoemostasis model assessment. Patients with type 2 DM then were placed on rosiglitazone (4 mg/day, for 12 weeks) in addition coexistent medication, and baseline tests were repeated. There was no difference between mean t-PA levels of the two groups. PAI-1 levels were higher in diabetic patients than control subjects (p < 0.01). Diabetic patients had lower GFC and t-PA/PAI-1 levels than control subjects (p < 0.05, p < 0.05). PAI-1 levels were positively correlated with waist circumference in diabetic group (r = 0.4, p < 0.05). After rosiglitazone treatment, there was no difference in mean plasma levels of GFC, t-PA, PAI-1 and t-PA/PAI-1 in diabetics. Insulin sensitivity significantly improved after the addition of rosiglitazone treatment in diabetic patients (p < 0.01). The short-term and low-dose treatment with rosiglitazone in type 2 diabetic patients has no effects on the fibrinolytic system, although it improves insulin sensitivity.     

葛根素对冠心病患者胰岛素抵抗及内皮纤溶功能的影响

将72例冠心病（CHD）患者随机分为常规组（33例）和葛根素组（39例），均于治疗前及治疗结束时检测其血糖，胰岛素，纤溶指标，计算胰2岛素敏感性指数（ISI），并行静脉闭塞试验（VOT）；同时选择30例健康人作为对照组。结果显示：（1）与对照组比较，CHD患者的血浆胰岛素（FINS）浓度增高（P＜0．05），ISI降低（P＜0．05），VOT前及VOT时内皮细胞型纤溶酶原激活物（t-PA)活性降低（P＜0．01），纤溶酶原激活物抑制物－1（PAI－1）活性增高（P＜0．01）。FINS，ISI与纤溶指标存在高度线性相关意义。（2）葛根素组治疗后FINS，PAI－1下降（P＜0．01），ISI，VOT前及VOT时t-PA增高（P＜0．05，＜0．01），与常规组治疗后比较均具有显著性差异（P＜0．05，P＜0．01）。认为葛根素能改善CHD患者的胰岛素抵抗（IR）及与其密切相关的内皮纤溶功能。     

Diabetes and impaired glucose tolerance prevalences in Turkish patients with impaired fasting glucose

Impaired fasting glucose (IFG) like impaired glucose tolerance (IGT) has increased risk of progressing to diabetes mellitus (DM). The aim of the study was to evaluate prevalance of IGT and type 2 DM with oral glucose tolerance test (OGTT) in Turkish patients who had fasting glucose of 110 and 125 mg/dl. Hundred and forty-eight (67.3%) women and 72 (32.7%) men (30-65 years old with mean age of 51.3 +/- 8.7 year) who had fasting glucose range 110-125 mg/dl were evaluated with OGTT. Seventy-two patients had IGT (32.8%), 74 (33.6%) patients had type 2 diabetes and 74 (33.6%) patients had normal glucose tolerance (NGT). Mean fasting glucose and insulin levels were higher in the IGT group than in the NGT group. Mean level of total cholesterol was higher in DM than that in NGT and IGT groups. Mean triglyceride (TG) (P = 0.476), high-density lipoprotein (HDL) (P = 0.594), low-density lipoprotein (LDL) (P = 0.612), Apoproteine A (P = 0.876), Apoproteine B (P = 0.518), uric acid (P = 0.948) and ferritin (P = 0.314) were found higher in diabetic patients. Lipoproteine a (P = 0.083), fibrinogen (P = 0.175) and hsCRP (P = 0.621) levels were higher in IGT. Mean HOMA S% levels of NGT, IGT and DM were found to be 65.0 +/- 13.0%, 60.9 +/- 16.0% and 50.1 +/- 11.1%, respectively. HOMA B% levels were measured to be 80.4 +/- 29.1% in NGT, 85.3 +/- 14.59% in IGT and 60.1 +/- 10.1% in DM. Significant difference was found between IFG and DM (P = 0.043) groups. The prevalences of diabetes and IGT were found to be 33.63 and 32.7% in IFG, respectively.     

Increased PAI-1 and tPA antigen levels are reduced with metformin therapy in HIV-infected patients with fat redistribution and insulin resistance

Cardiovascular disease (CVD) risk associated with fat redistribution seen among HIV-infected individuals remains unknown, but may be increased due to hyperlipidemia, hyperinsulinemia, increased visceral adiposity, and a prothrombotic state associated with these metabolic abnormalities. In this study we characterized plasminogen activator inhibitor-1 (PAI-1) and tissue-type plasminogen activator (tPA) antigen levels, markers of fibrinolysis and increased CVD risk, in HIV lipodystrophic patients compared to controls. Furthermore, we investigated the effect of treatment with metformin on PAI-1 and tPA antigen levels in patients with HIV-associated fat redistribution. Eighty-six patients (age 43 +/- 1 yr, BMI 26.1 +/- 0.5 kg/m(2)) with HIV and fat redistribution were compared to 258 age- and BMI-matched subjects from the Framingham Offspring study. In addition, 25 HIV-infected patients with fat redistribution and fasting insulin >15 microU/mL [104 pmol/L] or impaired glucose tolerance, but without diabetes mellitus were enrolled in a placebo-controlled treatment study of metformin 500 mg twice daily. PAI-1 and tPA antigen levels were significantly increased in patients with HIV related fat redistribution compared to Framingham control subjects (46.1 +/- 4 vs 18.9 +/- 0.9 microg/L PAI-1, 16.6 +/- 0.8 vs. 8.0 +/- 0.3 microg/L tPA, P = 0.0001). Among patients with HIV infection, a multivariate regression analysis including age, sex, waist-to-hip ratio, BMI, smoking status, protease inhibitor use and insulin area under the curve (AUC), found gender and insulin AUC were significant predictors of tPA antigen. Twelve weeks of metformin treatment resulted in decreased tPA antigen levels (-1.9 +/- 1.4 vs +1.4 +/- 1.0 microg/L in the placebo-treated group P = 0.02). Similarly, metformin resulted in improvement in PAI-1 levels (-8.7 +/- 2.3 vs +1.7 +/- 2.9 microg/L, P = 0.03). Change in insulin AUC correlated significantly with change in tPA antigen (r = 0.43, P = 0.03). PAI-1 and tPA antigen, markers of impaired fibrinolysis and increased CVD risk, are increased in association with hyperinsulinemia in patients with HIV and fat redistribution. Metformin reduces PAI-1 and tPA antigen concentrations in these patients and may ultimately improve associated CVD risk.     

老年糖尿病患者脂肪餐后血管内皮活性因子的变化

目的 观察老年糖尿病患者脂肪餐后血管内皮活性因子的动态变化及其与血脂的关系. 方法 选择老年糖尿病患者(糖尿病组)36例和健康老年人(对照组)20例进行6 h脂肪餐负荷试验.糖尿病组根据空腹和脂肪餐后4 h三酰甘油(TG)水平分为空腹TG增高组、餐后TG增高组和餐后TG正常组3个亚组.各组均测定脂肪餐前后血清一氧化氮(NO)、内皮素-1(ET-1)、纤溶酶原激活物抑制物-1(PAI-1)、组织型纤溶酶原激活物(t-PA)的浓度,并分析与TG的相关性. 结果 (1)NO、ET-1及NO/ET-1的变化:对照组脂肪餐后2 h NO浓度显著升高、ET-1水平显著降低,6 h均恢复至餐前水平;而糖尿病各亚组脂肪餐后NO逐渐降低、ET-1逐渐升高,餐后6 h变化最为明显.与对照组比较,糖尿病各亚组脂肪餐后各点NO/ET-1均显著降低(P<0.01),而餐后TG增高组和空腹TG增高组与餐后TG正常组比较差异有统计学意义(P<0.05或P<0.01).(2)t-PA、PAl-1及PAl-1/t-PA的变化:各组脂肪餐后4 h PAl-1水平轻度升高、t-PA水平轻度降低;与对照组比较,糖尿病组PAI-1/t-PA显著升高,糖尿病各亚组比较,餐后TG增高组和空腹TG增高组显著高于餐后TG正常组(P<0.05或P<0.01).(3)与TG的相关性分析:直线相关分析显示,糖尿病组TG与NO、t-PA显著负相关(r=-0.360,P<0.05;r=-0.649,P<0.01),与ET-1、PAI-1显著正相关(r=0.421,P<0.01;r=0.520,P<0.01). 结论 老年糖尿病患者存在血管内皮活性因子平衡失调,血脂异常可加重这一改变和血管内皮功能的损伤.     

Acute hyperglycemia alters von Willebrand factor but not the fibrinolytic system in elderly subjects with normal or impaired glucose tolerance.

To assess whether acute hyperglycemia affects fibrinolytic balance in elderly subjects with normal glucose tolerance (NGT) or impaired glucose tolerance (IGT), 40 non-obese elderly subjects (20 NGT, age 68 +/- 8 years; and 20 IGT, age 69 +/- 11 years) were studied. On two experimental days, randomly allocated and spaced 1 week apart, plasma concentrations of glucose, insulin, fibrinogen, tissue plasminogen activator, plasminogen activator inhibitor type 1 and von Willebrand factor (vWF) were measured in each subject at baseline (0) and 30, 60, 90, 120 min after the ingestion of 75 g glucose or a similarly sweet dose of aspartame (250 mg) (control test). In both NGT and IGT elderly subjects, tissue plasminogen activator, plasminogen activator inhibitor type 1 and fibrinogen plasma levels did not significantly change after both oral aspartame and glucose load. In IGT subjects, vWF plasmatic levels decreased after glucose (not aspartame) oral load, reaching the minimum level at 90 min after load (82.7 +/- 7.8 versus 93.7 +/- 10.2, P <0.01). These results demonstrate that acute hyperglycemia does not modify plasma fibrinolysis in elderly subjects. The decrease of plasma concentration of vWF in IGT elderly subjects requires cautious interpretation and further extensive investigations.     

Effect of amlodipine-atorvastatin combination on fibrinolysis in hypertensive hypercholesterolemic patients with insulin resistance

BACKGROUND: The aim of this study was to evaluate the effect of the amlodipine-atorvastatin combination on plasma tissue plasminogen activator (t-PA) and plasminogen activator inhibitor type 1 (PAI-1) activity in hypercholesterolemic, hypertensive patients with insulin resistance. METHODS: The study population included 45 patients, aged 41 to 70 years, with mild to moderate essential hypertension (diastolic blood pressure [BP] > or = 95 and < or = 105 mm Hg), hypercholesterolemia (total cholesterol > 200 and < 350 mg/dL), and insulin resistance (HOMA index > 2.5) After a 4-week wash-out period, they were randomized to amlodipine (5 mg) or atorvastatin (20 mg) or their combination at the same oral dosage for 12 weeks in three cross-over periods each separated by a 4-week placebo period (3 by 3 latin square design). At the end of the placebo wash-out and of each treatment period, office BP, total cholesterol, PAI-1, and t-PA activity were evaluated. RESULTS: The amlodipine-atorvastatin combination, in addition to the expected hypocholesterolemic effect, produced: 1) a greater decrease in PAI-1 activity (-10.2 U/mL, P <.01 v placebo) and an even greater increase in t-PA activity (+0.26 U/mL, P <.01 v placebo) than amlodipine (-0.5 U/mL for PAI-1, P = not significant; +0.17 U/mL for t-PA, P <.01 v placebo) and atorvastatin alone (respectively, -9.9 U/mL, P <.01 v placebo and +0.08 U/mL, P <.05 v placebo); and 2) a greater systolic BP/diastolic BP mean reduction (-22/17 mm Hg, P <.005 v placebo) than amlodipine (-18/14 mm Hg, P <.01 v placebo) and atorvastatin alone (-2.8/3.8 mm Hg, P <.05 v placebo only for diastolic BP). CONCLUSIONS: The positive effect on fibrinolytic balance and BP control observed suggests that in hypertensive, hypercholesterolemic patients with impaired fibrinolysis, the combination of amlodipine and atorvastatin could be the treatment of choice.