Soluble tumor necrosis factor receptor 2 is independently associated with pulse wave velocity in nonobese Japanese patients with type 2 diabetes mellitus.

The aim of the present study was to investigate the factors contributing to pulse wave velocity (PWV) in patients with type 2 diabetes mellitus. We focused on tumor necrosis factor (TNF) including soluble TNF receptors (sTNF-R1, sTNF-R2) in this study because TNF seems to be associated with the progression of atherosclerosis and because the relationships between PWV and TNF were not yet examined in type 2 diabetic patients. Univariate regression analyses showed that PWV was positively correlated with age (r=0.492, P<.001), diabetes duration (r=0.251, P=.021), systolic (r=.595, P<.001) and diastolic (r=0.248, P=.022) blood pressure, antihypertensive medication (r=0.268, P=.013), and the concentrations of sTNF-R1 (r=0.354, P=.001) and sTNF-R2 (r=0.415, P<.001). Although there was a positive correlation between TNF-alpha and sTNF-R1 (r=0.382, P<.001) or sTNF-R2 (r=0.394, P<.001), TNF-alpha was not associated with PWV. Other variables including gender were not associated with PWV. Multiple regression analyses showed that PWV was independently predicted by the level of age (F=15.1), systolic blood pressure (F=31.6), and sTNF-R2 (F=5.2), which explained 49.2% of the variability of PWV. From these results, it can be concluded that serum soluble TNF receptor is an important independent factor associated with aortic PWV in type 2 diabetic patients.

Leptin, triglycerides, and interleukin 6 are independently associated with C-reactive protein in Japanese type 2 diabetic patients.

The aim of the present study was to investigate the factors contributing to the concentration of serum C-reactive protein in type 2 diabetic patients. One hundred and 48 Japanese type 2 diabetic patients were studied. In conjunction with C-reactive protein (CRP), BMI, systolic and diastolic blood pressure, glycosylated hemoglobin (HbA1c), fasting concentrations of plasma glucose, and serum lipids (triglycerides, HDL cholesterol, and total cholesterol), interleukin 6 (IL-6), and leptin were measured. Insulin resistance was also estimated by the insulin resistance index of homeostasis model assessment (HOMA-IR). With univariate analysis, serum CRP was positively correlated with BMI (r=0.281, P<0.001), diastolic blood pressure (r=0.176, P=0.048), triglycerides (r=0.293, P<0.001), HOMA-IR (r=0.294, P<0.001), IL-6 (r=0.323, P<0.001), and leptin (r=0.330, P<0.001), and negatively correlated with HDL cholesterol (r=-0.181, P=0.028). Multiple regression analyses showed that serum CRP was independently predicted by the level of IL-6 (P<0.001, F=4.04), leptin (P<0.001, F=7.09), and triglycerides (P<0.001, F=15.13), which explained 17.6% of the variability of serum CRP concentration in these patients. From these results, it can be concluded that along with IL-6 and triglycerides, leptin is another important independent factor that is associated with CRP in Japanese type 2 diabetic patients.

Interleukin 6, adiponectin, leptin, and insulin resistance in nonobese Japanese type 2 diabetic patients.

The aim of the present study was to investigate the relationships between interleukin 6 (IL-6) and insulin resistance, serum leptin, serum adiponectin, or serum lipids including triglycerides in 98 nonobese Japanese type 2 diabetic patients. Insulin resistance was estimated by the insulin resistance index of homeostasis model assessment (HOMA-IR). Serum IL-6 concentration was negatively correlated to high-density lipoprotein cholesterol (r = -0.295, P = .004), but was not associated with HOMA-IR (r = 0.016, P = .871), body mass index (BMI) (r = 0.090, P = .375), systolic (r = 0.169, P = .116) and diastolic (r = -0.061, P = .570) blood pressures, leptin (r = 0.062, P = .544), and adiponectin (r = -0.020, P = .841) in these patients. In contrast, serum leptin level was positively correlated to HOMA-IR (r = 0.291, P = .004), BMI (r = 0.338, P < .001), and systolic blood pressure (r = 0.241, P = .025). Serum adiponectin level was negatively correlated to HOMA-IR (r = -0.288, P = .005), BMI (r = -0.308, P = .002), diastolic blood pressure (r = -0.269, P = .012), and triglycerides (r = -0.338, P < .001), and positively correlated to high-density lipoprotein cholesterol (r = 0.300, P = .003) in our patients. From these results, it can be suggested that fasting serum IL-6 is not a major factor responsible for the evolution of insulin resistance in nonobese Japanese type 2 diabetic patients.

Coexistence of insulin resistance and inflammation effectively predicts cardiac disease but not stroke in Japanese patients with type 2 diabetes mellitus.

It is well known that insulin resistance (IR) and inflammation (IF) are associated with macroangiopathy. However, whether IR and IF are related to cardiac disease (myocardial infarction, angina pectoris, and heart failure), stroke or both remains elusive. The present hospital-based prospective study was designed to investigate this issue. The study subjects were 300 Japanese patients with type 2 diabetes mellitus and negative history of cardiac disease and stroke. IR (K index of insulin tolerance test; K(ITT)) and IF (high-sensitivity C-reactive protein [hs-CRP]) were measured in each patient at baseline. Patients were followed-up for a mean period of 5.5 years. The time of first evidenced cardiac disease or stroke was monitored. During the follow-up, 35 patients developed cardiac disease and 26 patients developed stroke. Age, smoking, K(ITT), and hs-CRP were independently related to cardiac disease, while age, systolic blood pressure, low HDL, and anti-platelet drug use were independently related to stroke. When patients were subdivided into IR(-) and IR(+), and IF(-) and IF(+), Kaplan-Meier survival analysis showed that the rate of cardiac disease, but not of stroke, was significantly higher in IR(+)IF(+) than IR(-)IF(-) patients (p < 0.01). In conclusion, coexistence of IR and IF effectively predicted cardiac disease but not stroke in Japanese patients with type 2 diabetes mellitus.

Sitagliptin Attenuates the Progression of Carotid Intima-Media Thickening in Insulin-Treated Patients With Type 2 Diabetes: The Sitagliptin Preventive Study of Intima-Media Thickness Evaluation (SPIKE): A Randomized Controlled Trial.

OBJECTIVE: The effect of additional treatment with oral hypoglycemic agents on the progression of atherosclerosis remains unknown in insulin-treated patients with type 2 diabetes mellitus (T2DM). We assessed the effects of sitagliptin, a dipeptidyl peptidase 4 inhibitor, on carotid intima-media thickness (IMT) in T2DM. RESEARCH DESIGN AND METHODS: This prospective, randomized, open-label, blinded end point, multicenter, parallel-group, comparative study included 282 insulin-treated patients with T2DM free of a history of apparent cardiovascular diseases who were recruited at 12 clinical units and randomly allocated to either the sitagliptin group (n = 142) or the control group (n = 140). The primary outcomes were changes in mean and maximum IMT of the common carotid artery measured by echography at the end of a 104-week treatment period. RESULTS: Sitagliptin had a more potent glucose-lowering effect compared with the conventional treatment (-0.5 ± 1.0% vs. -0.2 ± 0.9%; P = 0.004), without increasing hypoglycemic episodes or body weight. Changes in the mean and left maximum IMT, but not right maximum IMT, of the common carotid arteries were significantly greater after sitagliptin treatment compared with conventional treatment (-0.029 [SE 0.013] vs. 0.024 [0.013] mm [P = 0.005]; -0.065 [0.027] vs. 0.022 [0.026] mm [P = 0.021]; -0.007 [0.031] vs. 0.027 [0.031] mm [P = 0.45], respectively). Over 104 weeks, sitagliptin, but not conventional treatment, significantly reduced the mean IMT and left maximum IMT of common carotid arteries relative to the baseline. CONCLUSIONS: Sitagliptin attenuated the progression of carotid IMT in insulin-treated patients with T2DM free of apparent cardiovascular disease compared with conventional treatment.

Inflammation and insulin resistance are independently related to all-cause of death and cardiovascular events in Japanese patients with type 2 diabetes mellitus.

Insulin resistance (IR)/hyperinsulinemia and low-grade inflammation (high-sensitivity C-reactive protein [hs-CRP]) can predict cardiovascular disease. However, because IR and inflammation (IF) have not been evaluated simultaneously, it is not known whether IR and IF are independently related to cardiovascular disease. Furthermore, the combined effect of IR and IF on the prediction of cardiovascular disease is presently unknown. Thus, we measured insulin sensitivity (K index of the insulin tolerance test; KITT) and hs-CRP in 350 Japanese patients with type 2 diabetes, and followed them for 1-7 years (mean, 4.5 years). During the follow-up, 33 patients died and 53 patients developed non-fatal coronary artery disease or stroke (endpoint). Age, systolic blood pressure, current smoking, past history of cardiovascular disease, KITT, and hs-CRP independently and significantly correlated with endpoint. One-S.D. difference was associated with a significant increase of relative risk in KITT (1.45; 95% CI 1.09-1.91) and hs-CRP (1.30; 1.04-1.67). When patients were subdivided to tertile, the relative risk in the highest tertile of KITT was 1.76 (95% CI 1.01-3.11) and hs-CRP was 2.00 (1.03-3.85) compared with the patients with lowest tertile. The relative risk in the highest tertile of both KITT and hs-CRP was 5.32 (1.18-24.0) compared with the lowest tertile of both values. In conclusion, low-grade IF and IR are independently related to all-cause of death and cardiovascular disease in Japanese patients with type 2 diabetes. Coexistence of low-grade IF and IR amplify this effect.

Correlation between common carotid arterial wall thickness and ischemic stroke in patients with type 2 diabetes mellitus.

If a strong association between intima-media thickness of the common carotid artery (CCA-IMT) and ischemic stroke can be determined in diabetic subjects, it may be a useful predictor to help identify patients at high risk of ischemic stroke. To investigate the relative contribution of CCA-IMT to ischemic stroke in patients with type 2 diabetes, we measured CCA-IMT and other conventional risk factors in 438 Japanese patients with type 2 diabetes, including 45 with ischemic stroke and 393 controls. Stroke patients were characteristically and significantly older with higher body mass index, longer duration of diabetes, likely to be smokers, higher blood pressure, and higher total cholesterol compared with the controls. CCA-IMT in stroke patients (1.23 +/- 0.04 mm) was significantly greater than in control patients (0.95 +/- 0.01 mm, P <.01). CCA-IMT in stroke patients was still significantly greater than controls after adjustment for age, sex, body mass index, and smoking status (P <.05). A 0.1-mm increase in CCA-IMT was associated with 1.80-fold increase in the odds ratio of stroke in diabetic patients (95%confidence interval [CI], 1.49 to 2.17; P <.01). Four independent factors were found to correlate significantly with CCA-IMT: age, systolic blood pressure, HbA(1c), and high-density lipoprotein (HDL) cholesterol. Thus, thickening of the intima-media of common carotid arteries is associated with ischemic stroke in type 2 diabetic patients. To prevent ischemic stroke, strict control of diabetes, hypertension, and dyslipidemia and monitoring of CCA-IMT may be important.

High serum concentrations of soluble E-selectin correlate with obesity but not fat distribution in patients with type 2 diabetes mellitus.

Serum concentrations of soluble adhesion molecules, eg, intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), and E-selectin are elevated in patients with type 2 diabetes. However, little is known about the role of obesity or abnormal fat distribution in inducing upregulation of adhesion molecules. To investigate this issue, soluble ICAM-1, VCAM-1, and E-selectin levels were evaluated in 40 obese and 30 nonobese patients with type 2 diabetes. Both groups were matched for age, sex, and glycosylated hemoglobin (HbA(1c)) levels. Computed tomography (CT) was used to measure the abdominal subcutaneous and visceral fat areas. Soluble ICAM-1 and VCAM-1 levels did not differ significantly between obese and nonobese patients. However, serum concentrations of soluble E-selectin were significantly higher in obese than in nonobese patients (90 +/- 7 v 56 +/- 4 ng/mL, P <.01). Soluble E-selectin levels significantly correlated with body mass index, subcutaneous fat area, and visceral fat area (Rho = 0.48, 0.37, and 0.30, respectively). Stepwise multiple regression analysis showed that body mass index (F = 16.7), but not subcutaneous and visceral fat areas (F = 0.29 and 0.01, respectively), significantly and independently correlated with soluble E-selectin levels. Our results suggest that obesity may induce endothelial activation or increased shedding of cell surface E-selectin that leads to subsequent increase in soluble E-selectin levels. The high serum concentrations of E-selectin closely correlated with increased total fat volume, but not with regional fat distribution.

Combination therapy of alpha-glucosidase inhibitor and a sulfonylurea compound prolongs the duration of good glycemic control.

The aim of this study was to investigate whether combination therapy of alpha-glucosidase inhibitor and a sulfonylurea (SU) drug can prolong the duration of good glycemic control compared with SU alone in patients with type 2 diabetes. The open prospective study included 124 Japanese patients with type 2 diabetes and inadequate glycemic control (hemoglobin A(1c) [HbA(1c)] gt; 7.0%). Patients were given either voglibose plus a SU compound (glibenclamide or gliclazide, n = 61) or SU drug alone (n = 63). The first 6-month run-in period (targeted to HbA(1c) /= 8.0%). Fifty patients on combination therapy and 48 patients on SU alone completed the trial. During the follow-up, 21 patients on combination therapy and 30 patients on SU alone showed deterioration of glycemic control and reached the endpoint (P =.04). The combination therapy significantly prolonged the duration of good glycemic control (HbA(1c) < 8.0%) compared with SU alone by Kaplan-Meier estimated survival analysis using a log-rank test (P =.02). Thus, combination therapy with voglibose and a SU agent prolongs the duration of good glycemic control compared with SU alone in patients with type 2 diabetes.

Serum concentrations of soluble adhesion molecules are related to degree of hyperglycemia and insulin resistance in patients with type 2 diabetes mellitus.

To investigate the relationships between serum concentrations of soluble adhesion molecules and hyperglycemia, insulin resistance, or other conventional risk factors in type 2 diabetes, we measured soluble intercellular adhesion molecule-1 (sICAM-1), vascular cell adhesion molecule-1 (sVCAM-1), E-selectin (sE-selectin), insulin sensitivity, and conventional risk factors in 150 Japanese type 2 diabetic patients without apparent diabetic macroangiopathy. High serum concentrations of sVCAM-1 and sE-selectin were observed in patients with type 2 diabetes. Serum concentrations of soluble adhesion molecules were not significantly influenced by sex, hypertension, dyslipidemia, or microangiopathy. Spearman correlation showed that sVCAM-1 concentrations correlated significantly with fasting plasma glucose (FPG), fasting C-peptide, and insulin sensitivity [K index of the insulin tolerance test (K(ITT))] (rho=0.19,0.23, and -0.23, respectively). Soluble E-selectin concentrations correlated significantly with body mass index (BMI), FPG, fasting C-peptide, insulin sensitivity, and triglyceride (rho=0.33,0.42,0.26,-0.48, and 0.29, respectively). Multiple regression analysis showed that FPG, fasting C-peptide, and total cholesterol were independent factors that correlated with sVCAM-1 levels. BMI, FPG, and insulin sensitivity were independent factors that correlated with sE-selectin levels. Serum concentrations of sE-selectin significantly increased associated with clustering of conventional risk factors those obesity, hypertension, dyslipidemia, and current smoking (P<0.01). Thus, sVCAM-1 and sE-selectin levels are related to both hyperglycemia and insulin resistance. Soluble E-selectin levels may be related to obesity, hyperglycemia, and insulin resistance and may reflect the presence of a multiple risk factor clustering syndrome.

Metformin attenuates progression of carotid arterial wall thickness in patients with type 2 diabetes.

To investigate the anti-atherogenic effect of metformin, we prospectively evaluated the effect of metformin treatment on common carotid intima-media thickness (CCA-IMT) in patients with type 2 diabetes. A 2-year open prospective study was performed. Thirty-six patients were treated with metformin (500-750 mg per day). CCA-IMT was measured after 1- and 2-year treatment. Changes in CCA-IMT were compared with control patients. After 2-year metformin therapy, the progression of CCA-IMT was significantly less than 56 control patients (0.02+/-0.08 mm versus 0.07+/-0.08 mm, P<0.01). Metformin therapy did not alter body weight, blood pressure, HbA1c, and serum lipids relative to the control. Thus, metformin attenuates the progression of CCA-IMT. This anti-atherogenic effect is not mediated through changes in classical cardiovascular risk factors.

Rationale, design, and baseline characteristics of a clinical trial for prevention of atherosclerosis in patients with insulin-treated type 2 diabetes mellitus using DPP-4 inhibitor: the Sitagliptin Preventive study of Intima-media thickness Evaluation (SPIKE).

BACKGROUND: Sitagliptin, a dipeptidyl peptidase-4 (DPP-4) inhibitor, is currently used to achieve glycemic targets in patients with type 2 diabetes mellitus (T2DM). The addition of DPP-4 inhibitors to ongoing insulin therapy is expected to reduce insulin dosage, leading to a reduction in the frequency of hypoglycaemia and/or weight gain. Recent studies have demonstrated potential anti-atherosclerotic effects for DPP-4 inhibitors. The aim of the present ongoing study is to assess the effects of sitagliptin on the progression of atherosclerosis in patients with insulin-treated T2DM using carotid intima-media thickness (IMT), an established marker of cardiovascular disease. METHODS AND DESIGN: The Sitagliptin Preventive study of Intima media thickness Evaluation (SPIKE) is a prospective, randomized, open-label, blinded-endpoint, multicenter, parallel-group, comparative study. Between February 2012 and September 2012, 282 participants who failed to achieve glycemic control despite insulin therapy were recruited at 12 clinics and randomly allocated to the sitagliptin group (n = 142) or the control group (n = 140). Primary outcomes are changes in maximum and mean IMT of the common carotid artery after 24-month treatment period measured by carotid arterial echography. Secondary outcomes include changes in glycemic control, parameters related to beta-cell function and diabetic nephropathy, occurrence of cardiovascular events and adverse events such as hypoglycaemia, and biochemical markers of vascular function. DISCUSSION: The present study is designed to assess the effects of sitagliptin on the progression of carotid IMT. Results will be available in the near future, and the findings are expected to provide new strategy to prevent atherosclerosis in patients with insulin-treated T2DM. CLINICAL TRIAL REGISTRATION: UMIN000007396.

Circulating TNF receptor 2 is associated with the development of chronic kidney disease in non-obese Japanese patients with type 2 diabetes.

AIMS: Chronic low-grade inflammation and/or obesity are suggested to induce chronic kidney disease (CKD) in patients with type 2 diabetes. This cross-sectional study was performed to investigate the relationship between inflammatory biomarkers and CKD in non-obese patients with type 2 diabetes. METHODS: 106 non-obese Japanese patients with type 2 diabetes were recruited for the measurement of GFR, TNF, HMW adiponectin, leptin, hsCRP and some variables including urinary albumin. BMI, serum creatinine, and urinary albumin levels were 22.2 ± 0.2 kg/m(2) (17.1-24.9 kg/m(2)), 0.76 ± 0.02 mg/dl (0.39-1.38 mg/dl), 40.4 ± 4.3mg/gCr (1.6-195.0mg/gCr), respectively. They were stratified into two groups based on the value of eGFR: low eGFR (eGFR<60 ml/min/1.73 m(2)) and normal eGFR (eGFR>60 ml/min/1.73 m(2)). Logistic regression analysis was used for statistical analysis. RESULTS: Whereas univariate logistic regression analysis showed that gender, diabetes duration, triglyceride, HDL cholesterol, uric acid, urinary albumin, and soluble TNF receptors (sTNF-R1, sTNF-R2) are associated with the development of stage 3 CKD, multivariate logistic regression analysis revealed that sTNF-R2 (Odds ratio 1.003, 95% confidence interval 1.000 to 1.005, P=0.030) showed significant associations with the development of stage 3 CKD. CONCLUSIONS: Circulating TNF receptor 2 is an independent risk factor for CKD in non-obese Japanese patients with type 2 diabetes.

Soluble adhesion molecule E-selectin predicts cardiovascular events in Japanese patients with type 2 diabetes mellitus.

Soluble adhesion molecule E-selectin (sE-selectin) is a marker of endothelial activation. To investigate whether high serum concentrations of sE-selectin could predict cardiovascular events, we followed 392 Japanese patients with type 2 diabetes mellitus who had no history of cardiovascular disease for a mean period of 6 years. The cardiovascular end points were defined as fatal and nonfatal myocardial infarction, angina pectoris, stroke, and sudden death. During the follow-up period, 51 patients reached end point. Patients who reached end point were significantly older and had longer duration of diabetes, higher systolic blood pressure, higher hemoglobin A1c, higher plasma glucose, higher sE-selectin, and lower high-density lipoprotein cholesterol compared with those free of such events. The mean serum concentration of sE-selectin was higher in patients who reached end point (81.1 +/- 32.2 ng/mL) than event-free patients (66.7 +/- 33.7 ng/mL, mean +/- SD; P < .01). Multiple logistic regression analysis identified age, systolic blood pressure, total cholesterol, sE-selectin, and low high-density lipoprotein cholesterol as independent factors related to cardiovascular events. The odds ratio for cardiovascular events for 1-SD increase in sE-selectin concentration was 1.45 (95% confidence interval, 1.22-1.71). Kaplan-Meier analysis demonstrated a significantly higher cardiovascular event rate in the highest tertile of sE-selectin compared with the lowest or middle tertile of sE-selectin (P < .01). The results suggest that high serum concentrations of sE-selectin can predict cardiovascular events in Japanese patients with type 2 diabetes mellitus.

Apolipoprotein B and insulin resistance are good markers of carotid atherosclerosis in patients with type 2 diabetes mellitus.

BACKGROUND: It is widely known that low-density lipoprotein cholesterol (LDL-C) is an established risk factor for atherosclerosis. However, recent studies reported that serum levels of apolipoprotein B (Apo B) and Apo B to apolipoprotein A-1 (Apo A-1) ratio were better predictors of atherosclerotic vascular disease compared with LDL-C. In this study, we investigated that Apo B concentrations and insulin resistance (HOMA-R) can be good markers of carotid atherosclerosis in patients with type 2 diabetes. METHODS: Sixty-six type 2 diabetic patients with carotid atherosclerosis and 66 age- and sex-matched patients without carotid atherosclerosis were compared. The usefulness in risk assessment of LDL-C, Apo B, and HOMA-R for carotid atherosclerosis were estimated by receiver-operating characteristics (ROC) curve analysis. The percentage of carotid atherosclerosis in combination with two of these markers was calculated. RESULTS: Type 2 diabetic patients with carotid atherosclerosis had significantly higher body mass index, higher blood pressure, higher LDL-C, and Apo B, and higher HOMA-R. The ranking of the area under the ROC curve was Apo B, HOMA-R, and LDL-C (0.70, 0.69, and 0.66, respectively). The percentage of patients with carotid atherosclerosis and high LDL-C was 60.7%, high LDL-C+high HOMA-R was 77.4%, and high Apo B+high HOMA-R was 90.9%, respectively. The usefulness of these combinations was significantly better than that of LDL-C alone (p<0.05 and p<0.01, respectively). CONCLUSIONS: In conclusion, the combination of Apo B and HOMA-R is a superior marker of carotid atherosclerosis compared with LDL-C alone in patients with type 2 diabetes.

Preorganized bis-zinc phosphodiester cleavage catalysts possessing natural ligands: a lesson pertinent to bimetallic artificial enzymes.

Two preorganized bis-zinc receptors (2 and 3) were synthesized wherein the metals were ligated with ligands present in natural phosphodiesterases: imidazoles and carboxylates. The intrametallic distance is near 4.5 A, that found in natural nucleases and other successful artificial nucleases. With only two imidazoles (2), the zinc binding affinities were not high enough to achieve cooperativity. Yet, with a third ligand, a carboxylate (3), cooperativity was found in the cleavage of HPNPP. The preorganization of 3 was achieved using a "steric gearing" strategy. The enhancement was 80-fold for cooperation between the two metals relative to a mono-metallic analogue (5). However, there was no observable enhancement in the hydrolysis of RNA using 3 relative to 5. Therefore, we conclude that placing two zinc atoms that are ligated with natural ligands at the appropriate distance for catalysis is not sufficient to enhance the cleavage of RNA, but is successful for activated RNA substrate mimics.