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Background: The intima-media thickness (IMT) of the carotid artery, as determined by ultrasonography, is useful for reflecting the extent of subclinical atherosclerosis. We investigated the relationship between IMT and the serum concentrations of small low-density lipoprotein (LDL) in diabetic patients. Methods: The study was conducted with 27 Type 2 diabetic patients (14 males and 13 females; mean age=62.6+/-8.3 years) and 12 age-matched healthy controls. The LDL subfraction was measured using a polyacrylamide gel electrophoresis method. Vascular endothelial growth factor (VEGF) and platelet-derived growth factor (PDGF) concentrations were measured by an enzyme immunoassay. The IMT was expressed as the maximum IMT (Max-IMT) and average IMT (Ave-IMT) of the carotid artery, measured by ultrasonography. Results: Both the IMT and the small LDL concentrations were significantly increased in the diabetic patients compared with the healthy participants. The IMTs were significantly correlated with small LDL concentration and small LDL/total LDL more than LDL concentrations by multivariate analysis. The IMTs were not significantly correlated with the serum VEGF or PDGF concentrations. The patients with a larger IMT had a significantly higher prevalence of hypertension or ischemic heart disease than did the patients with a normal IMT. Conclusions: The increased small LDL concentrations and small LDL/total LDL, in addition to total LDL concentrations, in Type 2 diabetic patients are closely associated with increased IMT of the carotid artery. [ABSTRACT FROM AUTHOR]

The hypoglycemic drug, troglitazone (TGZ) has antioxidant activity. Superoxide dismutase (SOD) removes superoxide produced by cells. We measured the response of SOD-like activity (ΔSOD) to ascorbic acid (AA) or TGZ using electron spin resonance at various glucose concentrations in polymorphonuclear leukocytes from 18 type 2 diabetic patients and 18 healthy controls. In control and diabetic subjects, ΔSOD in response to AA was dose-dependent (maximal effect at 100 ng/ml). Maximal response occurred 2 min after AA addition (50 ng/ml). In cells from diabetic patients, ΔSOD with 25 ng/ml AA was significantly less than for healthy controls. The ΔSOD with AA changed little at glucose concentration from 0 to 200 mg/dl. In patient and control cells, higher glucose concentrations (400 to 800 mg/dl) reduced ΔSOD with AA. Response patterns with TGZ resembled those with AA. ΔSOD with AA correlated positively with glycosylated hemoglobin A1c. Conclusions: The present data suggest that an amerioration of blood glucose on high levels in diabetic patients plays an important role in an antioxidant efficacy of TGZ and AA on leukocytes in patients. [Copyright &y& Elsevier]

Examines the effect of four analogs of K+-channel blockers on the stimulation of prolactin (Prl) and thyroid stimulating hormone (TSH) secretion. Secretion of Prl by acutely dispersed anterior pituitary cells; Implications of the differences in the role of K+ channels; Signal transduction.

Objective: CD26/DPP-4 is highly expressed by T cells, especially CD4+ T cells (T helper cells; Th) and may regulate the differentiation, maturation, or proliferation of these cells. We investigated the effects of sitagliptin, a DPP-4 inhibitor, on the absolute number and percentage of various subsets of circulating CD4+ T cells in patients with type 2 diabetes.Methods: We enrolled 30 consecutive patients (16 women and 14 men) with type 2 diabetes in a prospective, randomized, open-label, blinded endpoint study. Eligible participants were randomly assigned at a 2:1 ratio to either a sitagliptin group (sitagliptin at 50mg/day) or an active control group (glimepiride at 1mg/day). Patients were followed for 12 weeks with monthly review. Peripheral blood mononuclear cells were examined by flow cytometry for intracellular expression of cytokines (IFN-γ as a marker of Th1cells, IL-4 for Th2 cells, and IL-17 for Th17 cells) and for expression of CD4, CD25, and Foxp3 (regulatory T cells [Treg]).Results: Both groups showed similar improvement of glycemic control. The total number of CD4+ T cells was decreased by treatment with sitagliptin, while it did not change in the control group. The number and percentage of Th17 cells and Treg cells both decreased significantly in the sitagliptin group, but not in the control group. There was a significant positive correlation between changes in the percentage of Th17 cells and Treg cells after treatment with sitagliptin.Conclusions: Treatment with sitagliptin for 12 weeks reduced the number of circulating CD4+ T cells, especially Th17 and Treg cells, in patients with type 2 diabetes. [ABSTRACT FROM AUTHOR]

Abstract: The study was designed to investigate the effect of retinol binding protein (RBP)-4 on the phosphatidylinositol 3-kinase (PI3K) and mitogen-activated protein kinase (MAPK) pathways, which mediate the effects of insulin in vascular endothelial cells. The effects of RBP4 on nitric oxide (NO) and insulin-stimulated endothelin-1 (ET-1) secretion and on phosphorylation (p) of Akt, endothelial NO synthetase (eNOS), and extracellular signal-regulated kinase (ERK)1/2 were investigated in bovine vascular aortic endothelial cells (BAECs). RBP4 showed an acute vasodilatatory effect on aortic rings of rats within a few minutes. In BAECs, RBP4-treatment for 5min significantly increased NO production, but inhibited insulin-stimulated ET-1 secretion. RBP4-induced NO production was not inhibited by tetraacetoxymethylester (BAPTA-AM), an intracellular calcium chelator, but was completely abolished by wortmannin, a PI3K inhibitor. RBP4 significantly increased p-Akt and p-eNOS production, and significantly inhibited p-ERK1/2 production. Triciribine, an Akt inhibitor, and wortmannin significantly inhibited RBP4-induced p-Akt and p-eNOS production. Inhibition of Akt1 by small interfering RNA decreased p-eNOS production enhanced by RBP4 in human umbilical vein endothelial cells. In conclusion, RBP4 has a robust acute effect of enhancement of NO production via stimulation of part of the PI3K/Akt/eNOS pathway and inhibition of ERK1/2 phosphorylation and insulin-induced ET-1 secretion, probably in the MAPK pathway, which results in vasodilatation. [Copyright &y& Elsevier]

Abstract: An increase of serum ferritin, an indicator of body iron store, is associated with insulin resistance and with an increased risk of type 2 diabetes in the general population. A low serum adiponectin is also associated with insulin resistance. Recently, hepcidin was identified as a regulator of iron metabolism. We investigated whether serum adiponectin was associated with serum ferritin or prohepcidin, a precursor of hepcidin, in healthy subjects and patients with type 2 diabetes. We studied 65 healthy subjects and 104 patients with type 2 diabetes. A serum ferritin concentration ≥300ng/ml for men or ≥150ng/ml for women was defined as hyperferritinemia. Serum ferritin was significantly higher and serum prohepcidin was significantly lower in diabetic patients than in control subjects. Serum total and high molecular weight (HMW) adiponectin correlated negatively with serum ferritin in control subjects or diabetic patients, while serum total and HMW adiponectin correlated positively with serum prohepcidin in diabetic patients, but not in control subjects. Serum total and HMW adiponectin were lower in patients with hyperferritinemia than in those without it. In conclusion, serum ferritin was increased in type 2 diabetic patients, while serum prohepcidin was decreased. A high serum ferritin was associated with insulin resistance, and with low serum total and HMW adiponectin in patients with type 2 diabetes. [ABSTRACT FROM AUTHOR]

Abstract: We investigated the effects of low-dose pioglitazone (7.5mg/day) on serum high molecular weight (HMW) adiponectin and fluid retention (estimated from hematocrit) in 14 male and 16 female patients with type 2 diabetes. All of them were being treated with sulfonylureas and had poor glycemic control. Patients were given 7.5mg/day of pioglitazone and were followed for 12 weeks at monthly intervals. In all 30 patients, HbA1c was significantly decreased after 12 weeks of treatment with pioglitazone (8.2±0.7% vs. 7.4±0.8%, P <0.0001). Serum HMW adiponectin increased markedly from 5.2 (2.4, 8.6)μg/ml at baseline to 9.8 (4.1, 12.6)μg/ml at the end of pioglitazone treatment (P <0.0001). When the changes were evaluated separately for each sex, diabetic men showed no increase of body weight or BMI after treatment, while HbA1c decreased significantly, and did Hct. Serum HMW adiponectin increased significantly after treatment. In diabetic women, neither body weight nor BMI increased after treatment with pioglitazone, as was the case for the men. HbA1c decreased significantly, and did Hct. Serum HMW adiponectin increased significantly after treatment. In conclusion, low-dose pioglitazone therapy could significantly improved glycemic control and markedly increased serum HMW adiponectin in both male and female Japanese patients with type 2 diabetes. [Copyright &y& Elsevier]

The article focuses on the study that compares the effect of rosuvastatin and colestimide on adipokines and markers of oxidative stress and diabetic nephropathy in type 2 diabetic patients with hyperlipidemia. It states that 40 patients with the disease were recruited and assigned randomly to the two groups. Their blood and urine were assessed at the beginning of the study and after 12 weeks. The study found out that rosuvastatin and colestimide exert different beneficial effects.

Adiponectin is an adipocyte-specific secretory protein that is highly and specifically expressed in adipose tissue, and low plasma levels of adiponectin are associated with coronary artery disease (CAD). It has been suggested that high molecular weight (HMW) adiponectin is more important for vascular protection than total amount of adiponectin. To establish the clinical relevance of HMW adiponectin, we measured its serum levels in 149 patients with CAD. The levels were lower in vasospastic angina pectoris (3.4 ± 2.4 μg/ml, p <0.01), stable angina pectoris (3.3 ± 2.6 μg/ml, p <0.001), and healed myocardial infarction (3.8 ± 2.9 μg/ml, p <0.01) than chest pain syndrome (controls) (6.6 ± 5.4 μg/ml). The levels were also lower in multivessel CAD (3.4 ± 2.4 μg/dl) compared with single vessel CAD (4.2 ± 2.7 μg/ml, p <0.05) or no organic stenosis (5.1 ± 3.5 μg/ml, p <0.01). In univariate analysis, diabetes mellitus (p = 0.03), insulin resistance (p = 0.06), high-sensitivity C-reactive protein levels (p = 0.0012), and low HMW adiponectin levels (p = 0.0001) predicted cardiovascular events during 7 years of follow-up. However, multivariate analysis showed that only HMW adiponectin levels were an independent predictor of cardiovascular events (relative risk 2.79, 95% confidence interval 1.49 to 5.24, p = 0.0014). In conclusion, serum HMW adiponectin levels may serve as a predictor of future cardiovascular events in patients with CAD as well as a marker for severity of CAD. [Copyright &y& Elsevier]

Osteopontin (OPN) is a proinflammatory cytokine implicated in the chemoattraction of monocytes and the development of atherosclerosis. Peroxisome proliferator-activated receptor (PPAR)α, a ligand-activated transcription factor with pleiotropic anti-inflammatory effects in macrophages, is the molecular target for fibrates, which are frequently used to treat dyslipidemia in patients with type 2 diabetes at high risk for cardiovascular disease. In the present study, we examined the regulation of OPN by PPAPα agonists in macrophages and determined the effect of fibrate treatment on OPN plasma levels in patients with type 2 diabetes. Treatment of human macrophages with the PPAPα ligands bezafibrate or WY14643 inhibited OPN expression. PPARα ligands suppressed OPN promoter activity, and an activator protein (AP)-1 consensus site conferred this repression. Overexpression of c-Fos and c-Jun reversed the inhibitory effect of PPARα ligands on OPN transcription, and, in chromatin immunoprecipitation assays, PPARα ligands inhibited c-Fos and phospho-c-Jun binding to the OPN promoter. Moreover, c-Fos and phospho-c-Jun protein expression was inhibited by PPARα agonists, indicating that PPARα ligands suppress OPN expression through negative cross talk with AP-1-dependent transactivation of the OPN promoter. This inhibitory effect of PPARα ligands on OPN expression was absent in PPARα-deficient macrophages, suggesting a receptor-mediated mechanism of OPN suppression. Finally, treatment of type 2 diabetic patients with bezafibrate significantly decreased OPN plasma levels. These results demonstrate a novel mechanism whereby PPARα ligands may impact macrophage inflammatory responses and decrease early proinflammatory markers for cardiovascular disease. Diabetes 56:1662-1670, 2007 [ABSTRACT FROM AUTHOR]

Adiponectin (Acrp30), an adipocyte-derived protein, exists in serum as a trimer, a hexamer, and a high-molecular weight (HMW) form, including 12-18 subunits. Because HMW adiponectin may be biologically active, we measured it in serum using a novel enzyme-linked immunosorbent assay (ELISA) confirmed by gel filtration chromatography that the ELISA detected mainly adiponectin with 12-18 subunits, and we compared HMW with total adiponectin concentration in patients with type 2 diabetes. We next investigated the relationship between serum HMW and coronary artery disease (CAD) in 280 consecutive type 2 diabetic patients, including 59 patients with angiographically confirmed CAD. Total adiponectin was measured in serum by a commercially available ELISA. Like serum total adiponectin, HMW adiponectin correlated positively with HDL cholesterol and negatively with triglyceride, insulin sensitivity, creatinine clearance, and circulating inflammatory markers. Total and HMW adiponectin were significantly higher in women than in men, as was the HMW-to-total adiponectin ratio. Serum HMW and the HMW-to-total adiponectin ratio were significantly lower in men with than without CAD (P < 0.05, respectively). In women, the ratio, but neither total nor HMW adiponectin, tended to be lower when CAD was present. In conclusion, determination of HMW adiponectin, especially relative to total serum adiponectin, is useful for evaluating CAD in type 2 diabetic patients. Diabetes 55:1954-1960, 2006 [ABSTRACT FROM AUTHOR]

Abstract: In 70 nonobese inpatients with Type 2 diabetes [body mass index (BMI): 24.0±4.4 kg/m2], we examined circulating monocyte chemoattractant protein (MCP) -1 as a candidate marker of atherosclerosis by comparison with established markers: serum high-sensitivity C-reactive protein (hsCRP), plasma fibrinogen, and combined carotid artery intimal–medial thickness (IMT). In addition, an association was sought between circulating MCP-1 and urinary albumin excretion (UAE), reflecting diabetic renal microangiopathy. Serum MCP-1 was determined by enzyme-linked immunosorbent assay (ELISA). Patients were grouped by UAE: normoalbuminuria, below 30 mg/g of creatinine (Cr); microalbuminuria, 30 to 300 mg/g Cr; or macroalbuminuria, over 300 mg/g Cr. Serum MCP-1 for all participants, men, and women was 280.0±78.9, 269.0±68.8, and 294.9±87.9 pg/ml, respectively, showing no difference between genders. No correlation was noted between MCP-1 and hsCRP, fibrinogen, or carotid artery IMT. No correlation of MCP-1 was observed with age, duration of diabetes, fasting plasma glucose (FPG), hemoglobin (Hb) A1C, BMI, diastolic blood pressure (DBP), or serum lipid concentrations, but significant correlations were found with systolic blood pressure (SBP; R=.2723, P=.0225) and with log10-transformed (log) UAE (R=.3343, P=.0047). Patients with macroalbuminuria had significant higher circulating MCP-1 than did those with normo- or microalbuminuria (P=.0063 and P=.0188, respectively). By stepwise regression analysis, only log UAE independently predicted serum MCP-1 (β=.3700, P=.0020). Thus, in nonobese Type 2 diabetic patients, MCP-1 might not be a marker of atherosclerosis and might be influenced significantly by diabetic nephropathy. [Copyright &y& Elsevier]

Objective: We investigated the correlation between acute-phase reactants, ie, high-sensitivity C-reactive protein (hsCRP) or fibrinogen and diabetic complications. Methods: In 73 patients with type 2 diabetes, we investigated associations between both markers and carotid artery intimal medial complex thickness (IMT), heart rate variability, or urinary albumin excretion (UAE). Results: Log hsCRP and fibrinogen correlated significantly with each other (r = 0.3701, P = 0.0013). Fibrinogen correlated negatively with the coefficient of variation of RR intervals (CV(RR)) and positively with log UAE (r = -0.2433, P = 0.0381; r = 0.4815, P < 0.0001), while log hsCRP did not. Furthermore both log hsCRP and fibrinogen did not correlate with IMT. Conclusion: We concluded that despite their close correlation, fibrinogen compared with hsCRP might be closely associated with diabetic microangiopathy and that both markers might not correlate with IMT as a marker of macroangiopathy. [ABSTRACT FROM AUTHOR]

Objective: To determine whether plasma concentrations of thrombin-activatable fibrinolysis inhibitor (TAFI) in patients with type 2 diabetes were associated with components of metabolic syndrome (MS), including high-sensitivity C-reactive protein (hs-CRP), plasminogen activator inhibitor (PAI)-1, and LDL cholesterol.Research Design and Methods: We studied 136 consecutive patients with type 2 diabetes. Diagnosis of MS was diagnosed by current criteria. Hypercholesterolemia (HC) was defined as serum LDL cholesterol >140 mg/dl (3.6 mmol/l) or treatment with a statin. For comparisons, diabetic patients were divided into four groups: those with no MS and no HC (n = 38), with MS but not HC (n = 39), with no MS but with HC (n = 26), and with both MS and HC (n = 33).Results: Considering all patients with type 2 diabetes, plasma PAI-1 was strongly associated with MS components such as BMI, triglyceride, alanine aminotransferase, a homeostasis model assessment of insulin resistance, and hs-CRP. Plasma TAFI only correlated positively and independently with LDL cholesterol. Plasma concentrations of plasmin-alpha2-antiplasmin complex (PAP), a measure of fibrinolytic activity in blood, showed a significant negative correlation with plasma PAI-1 but not TAFI. Diabetic patients with both MS and HC had the highest serum hs-CRP concentrations and the lowest plasma PAP concentrations.Conclusions: LDL cholesterol is a main determinant of plasma TAFI in patients with type 2 diabetes. Coexistence of MS and HC synergistically accelerates inflammation and impairment of fibrinolysis via elevated concentrations of both TAFI and PAI-1, which inhibit fibrinolysis. [ABSTRACT FROM AUTHOR]

OBJECTIVE -- To determine whether plasma concentrations of thrombin-activatable fibrinolysis inhibitor (TAFI) in patients with type 2 diabetes were associated with components of metabolic syndrome (MS), including high-sensitivity C-reactive protein (hs-CRP), plasminogen activator inhibitor (PAI)-1, and LDL cholesterol. RESEARCH DESIGN AND METHODS -- We studied 136 consecutive patients with type 2 diabetes. Diagnosis of MS was diagnosed by current criteria. Hypercholesterolemia (HC) was defined as serum LDL cholesterol >140 mg/dl (3.6 mmol/l) or treatment with a statin. For comparisons, diabetic patients were divided into four groups: those with no MS and no HC (n = 38), with MS but not HC (n = 39), with no MS but with HC (n = 26), and with both MS and HC (n = 33). RESULTS -- Considering all patients with type 2 diabetes, plasma PAI-1 was strongly associated with MS components such as BMI, triglyceride, alanine aminotransferase, a homeostasis model assessment of insulin resistance, and hs-CRP. Plasma TAFI only correlated positively and independently with LDL cholesterol. Plasma concentrations of plasmin-α2-antiplasmin complex (PAP), a measure of fibrinolytic activity in blood, showed a significant negative correlation with plasma PAI-1 but not TAFI. Diabetic patients with both MS and HC had the highest serum hs-CRP concentrations and the lowest plasma PAP concentrations. CONCLUSIONS -- LDL cholesterol is a main determinant of plasma TAFI in patients with type 2 diabetes. Coexistence of MS and HC synergistically accelerates inflammation and impairment of fibrinolysis via elevated concentrations of both TAFI and PAI-1, which inhibit fibrinolysis. [ABSTRACT FROM AUTHOR]

Background: Diabetic nephropathy, especially when advanced, is associated with high prevalence of atherosclerotic cardiovascular disease in which inflammation and coagulation may play pathogenic roles. We investigated the relationships between diabetic nephropathy and coagulation, fibrinolysis, or inflammation in patients with Type 2 diabetes. Methods: We evaluated markers of inflammation and coagulation in 105 Type 2 diabetic patients with various grades of nephropathy and 49 healthy control subjects, in association with plasma total homocysteine (tHcy) measurements. Results: Plasma tHcy concentrations were significantly higher in diabetic patients than in controls (8.96±3.04 vs. 6.92±1.36 μmol/l, P<0.0001). Plasma concentrations of interleukin (IL)-6 were significantly higher in diabetic patients than in control subjects (P<0.0001). In diabetic patients, plasma tHcy correlated positively with urinary albumin, fibrinogen, IL-6 and plasmin-α2-antiplasmin complex (PAP), while plasma tHcy correlated negatively with creatinine clearance (Ccr) and protein C activity. After adjustment for Ccr, IL-6 and protein C activity were significantly associated with plasma tHcy. Plasma tHcy concentrations were significantly higher in patients with overt albuminuria than in those with normoalbuminuria or microalbuminuria, as were plasma concentrations of fibrinogen, prothrombin F1+2, and interleukin-6. Conclusions: Diabetic nephropathy is associated with elevated markers for both coagulation and inflammation. High plasma homocysteine may be a link between diabetic nephropathy and both chronic inflammation and hypercoagulability, increasing cardiovascular risk. [Copyright &y& Elsevier]

The authors describe a 52-year-old woman diagnosed with microscopic polyangiitis. She presented with abnormal liver function tests accompanied by fever, headache, and fatigue. Two months later, rapidly progressive necrotizing glomerulonephritis developed together with seropositivity for perinuclear antineutrophil cytoplasmic antibody. Although liver dysfunction from microscopic polyangiitis is very rare, especially at presentation, this diagnostic possibility should be kept in mind to permit prompt consideration of steroid therapy. [ABSTRACT FROM AUTHOR]

Objective: Three blood markers of inflammation (high-sensitivity C-reactive protein [hsCRP], interleukin [IL]-6, and fibrinogen) were compared with markers of atherosclerotic cardiovascular disease (CVD) (history of stroke or cardiac ischemia and measured toe-brachial index [TBI]) to determine whether inflammatory markers are associated with atherosclerosis in patients with type 2 diabetes.Research Design and Methods: Of 103 patients with type 2 diabetes, 26 had CVD. TBI was plethysmographically determined in both great toes. Serum hsCRP was immunonephelometrically determined. Plasma IL-6 was measured by an enzyme immunoassay.Results: Both ABI and TBI were lower in diabetic patients with CVD than in those without CVD (1.05 +/- 0.19 vs. 1.14 +/- 0.09, P < 0.05, and 0.75 +/- 0.20 vs. 0.95 +/- 0.21, P < 0.001, respectively). By linear regression, right TBI but not right ABI showed a significant negative correlation with serum hsCRP (r = -0.372, P < 0.01) and plasma fibrinogen (r = -0.224, P < 0.05). Serum hsCRP was also negatively correlated with lower TBI, but not lower ABI. We found no significant correlation between plasma IL-6 and ABI or TBI.Conclusions: TBI was strongly associated with CVD, serum hsCRP, and plasma fibrinogen. Of these inflammatory markers, serum hsCRP may be the most promising marker for vascular inflammation. [ABSTRACT FROM AUTHOR]

Objective: We compared plasma interleukin (IL)-18 concentrations in patients with type 2 diabetes with those in age-matched control subjects and investigated whether plasma IL-18 was associated with plasma total homocysteine (tHcy) concentration or carotid intimal-media wall thickness (IMT), an early marker of atherosclerosis, in these patients.Research Design and Methods: We measured plasma IL-18 in 103 type 2 diabetic patients and 45 age-matched control subjects. We also measured patients' plasma tHcy and serum high-sensitivity C-reactive protein (hs-CRP). IMT was evaluated for both common carotid arteries.Results: Plasma IL-18 was significantly higher in diabetic patients than in control subjects (203 +/- 153 vs. 118 +/- 37 pg/ml, P < 0.001). High IL-18 was defined as equaling or exceeding the mean + 2 SD of plasma IL-18 in control subjects (192 pg/ml). Patients with high IL-18 showed a greater carotid IMT than those with normal IL-18. Carotid plaques were more numerous in diabetic patients with high IL-18 than in those with normal IL-18. Plasma tHcy concentrations were significantly higher in patients with high IL-18 than in those with normal IL-18. Univariate and multivariate analyses showed a strong independent association between tHcy and IL-18. Plasma IL-18 also correlated positively with serum hs-CRP.Conclusions: In patients with type 2 diabetes, plasma IL-18 concentrations are greater than in nondiabetic subjects. Plasma IL-18 is an independent determinant of plasma tHcy, which is linked independently with atherosclerotic carotid wall thickening. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented in response to the article related to ocular myasthenia that appeared in the previous issue.

Retinal binding protein (RBP)-4 is a newly identified adipocytokine that can cause insulin resistance. The main purpose of the current study was to investigate the relationship between RBP4 and various markers related to insulin resistance, including triglyceride (TG), high-density lipoprotein cholesterol (HDL-C), blood pressure (BP), endothelial function, oxidative stress, inflammation, and diabetic complications in patients with type 2 diabetes. The effect of pioglitazone (a thiazolidinedione) on RBP4 was also examined. Circulating RBP4 levels were measured in 101 hospitalized patients with type 2 diabetes and in 22 non-hospitalized control subjects. Endothelial function and oxidative stress were evaluated using flow-mediated vasodilatation (FMD) and urinary 8-iso-prostaglandin-F2α, respectively. Pioglitazone was administered for 12 weeks at a dose of 30 mg/day in a further 22 patient with type 2 diabetes in outpatient department. There was a significant elevation of RBP4 levels in diabetic patients compared with healthy subjects. RBP4 showed significant positive correlations with TG, systolic BP and log urinary albumin excretion (UAE), and significant negative correlations with HDL-C and FMD. By stepwise regression analysis log UAE, TG and gender showed a significant association with RBP4. There was a significant elevation of RBP4 in patients with proliferative-diabetic retinopathy compared with non-diabetic retinopathy and simple-diabetic retinopathy patients. Pioglitazone therapy for 12 weeks did not significantly affect the RBP4 concentration. In conclusion, this current study indicates the possibility that circulating RBP4 levels are associated with variables related to insulin resistance and diabetic complications. [ABSTRACT FROM AUTHOR]

This study was designed to investigate the relationship between vascular endothelial function and diabetic microangiopathy (nephropathy, retinopathy, and neuropathy) in patients with type 2 diabetes. Furthermore, the association between endothelial function and macroangiopathy evaluated by intimal-medial complex thickness (IMT) was also investigated. Endothelial function was evaluated by measurement of flow-mediated dilatation (FMD) of the brachial artery. Diabetic nephropathy and neuropathy were assessed by urinary albumin excretion (UAE) and motor or sensory nerve conduction velocity (MCV, SCV), respectively, and retinopathy was evaluated by an ophthalmologist using the Davis classification. FMD was measured in 102 patients with type 2 diabetes and in 20 control subjects, and showed a tendency to be lower in the diabetic patients. A significant decrease was obtained in FMD in patients with proliferative diabetic retinopathy (PDR), compared with those in patients with no diabetic retinopathy (NDR). FMD showed significant positive correlations with MCV and SCV, and significant negative correlations with log UAE, systolic blood pressure (SBP) and diabetic duration, but no correlation was obtained between FMD and IMT. By stepwise regression analysis, MCV alone showed a significant association with FMD. In conclusion, the current study suggests that in patients with type 2 diabetes FMD is closely associated with all types of microangiopathy, with neuropathy being most strongly associated with FMD; however, FMD is not associated with macroangiopathy evaluated by IMT. [ABSTRACT FROM AUTHOR]

Obejective. To investigate short-term effects of pioglitazone or voglibose on serum concentrations of both total and high-molecular-weight (HMW) adiponectin measured with a novel sandwich enzyme-linked immunosorbent assay (ELISA) and on plasma fibrinolysis indicators, in type 2 diabetic patients with a second failure of treatment with sulfonylureas. Methods. Thirty-four diabetic patients were randomized to receive pioglitazone or voglibose treatment for 12 weeks, after which serum HMW adiponectin was measured. Plasma plasminogen activator inhibitor (PAI)-1 and thrombin-activatable fibrinolysis inhibitor (TAFI), a recently identified inhibitor of fibrinolysis, were measured as fibrinolysis inhibitors. Results. At baseline, serum HMW adiponectin correlated negatively with plasma TAFI in all patients with type 2 diabetes (r=0.367, P=0.0423). Both groups showed similar improvements in glycemic control. Serum total and HMW adiponectin increased in patients treated with pioglitazone, while showing no significant changes in patients treated with voglibose. The HMW/total adiponectin ratio increased significantly after treatment with pioglitazone (P=0.0004). Changes in HbA1c showed significant negative correlations with changes in serum HMW adiponectin in patients treated with pioglitazone (r=-0.694, P=0.0034). Plasma PAI-1 tended to decrease after pioglitazone treatment (P=0.0908), while plasma TAFI did not change. Conclusion. Increased serum HMW adiponectin may contribute to the improvement in glycemic control after pioglitazone treatment. Plasma PAI-1 decreased somewhat after treatment with pioglitazone, while plasma TAFI was unchanged by either drug. [ABSTRACT FROM AUTHOR]