The appropriateness of the routine performance of an oral glucose tolerance test (OGTT) to screen for diabetes mellitus (DM) during acute coronary syndrome hospitalization is still under debate.
A systematic search of databases (MEDLINE [1985 to March 2012], EMBASE [1985 to March 2012]) was conducted. All prospective cohort studies assessing the accuracy or reproducibility of an OGTT in ACS or non-ACS individuals were included. A bivariate model was used to calculate the pooled sensitivity (SEN), specificity (SPE), positive likelihood ratio (PLR), negative likelihood ratio (NLR), and diagnostic odds ratio (DOR). Heterogeneity was explored using subgroup analysis and meta-regression.
Fifteen studies with 8,027 participants were included (10 ACS and 5 non-ACS studies). The pooled results on SEN, SPE, PLR, NLR, and DOR were 0.70 (95% CI, 0.60-0.78), 0.91 (95% CI, 0.86-0.94), 7.6 (95% CI, 4.9-11.7), 0.33 (95% CI, 0.25-0.45), and 23 (95% CI, 12–41), respectively. The OGTT has a slightly lower SPE in diagnosing DM in ACS than in non-ACS patients (0.86 [95% CI 0.81-0.92] versus 0.95 [95% CI 0.93-0.98], p<0.01), while the SEN values are comparable (0.71 [95% CI 0.60-0.82] versus 0.67 [95% CI 0.54-0.81], p=0.43). After adjusting the interval between repeated tests and age, the meta-regression did not show a difference in DOR between ACS and non-ACS studies.
Despite the discrepancy in the interval between the two OGTTs, performing an OGTT in patients with ACS provides accuracy that is similar to that in in non-ACS patients. It is reasonable to screen patients hospitalized for ACS for previously undiagnosed DM using an OGTT.
Acute coronary syndrome; Oral glucose tolerance test; Accuracy; Meta-analysis
Cardiovascular risk factors (CVRF) may cluster in type 1 diabetes, analogously to the metabolic syndrome described in type 2 diabetes. The threshold of HbA1c above which lipid variables start changing behavior is unclear. This study aims to 1) assess the behavior of dyslipidemia according to HbA1c values; 2) detect a threshold of HbA1c beyond which lipids start to change and 3) compare the clustering of lipids and other non-lipid CVRF among strata of HbA1c individuals with type 1 diabetes.
Effects of HbA1c quintiles (1st: ≤7.4%; 2nd: 7.5-8.5%; 3rd: 8.6-9.6%; 4th: 9.7-11.3%; and 5th: >11.5%) and covariates (gender, BMI, blood pressure, insulin daily dose, lipids, statin use, diabetes duration) on dyslipidemia were studied in 1275 individuals from the Brazilian multi-centre type 1 diabetes study and 171 normal controls.
Body size and blood pressure were not correlated to lipids and glycemic control. OR (99% CI) for high-LDL were 2.07 (1.21-3.54) and 2.51 (1.46-4.31), in the 4th and 5th HbA1c quintiles, respectively. Hypertriglyceridemia increased in the 5th quintile of HbA1c, OR 2.76 (1.20-6.37). OR of low-HDL-cholesterol were 0.48 (0.24-0.98) and 0.41 (0.19-0.85) in the 3rd and 4th HbA1c quintiles, respectively. HDL-cholesterol correlated positively (0.437) with HbA1c in the 3rd quintile. HDL-cholesterol and insulin dose correlated inversely in all levels of glycemic control.
Correlation of serum lipids with HbA1c is heterogeneous across the spectrum of glycemic control in type 1 diabetes individuals. LDL-cholesterol and triglycerides worsened alongside HbA1c with distinct thresholds. Association of lower HDL-cholesterol with higher daily insulin dose is consistent and it points out to a role of exogenous hyperinsulinemia in the pathophysiology of the CVRF clustering. These data suggest diverse pathophysiological processes depending on HbA1c, refuting a unified explanation for cardiovascular risk in type 1 diabetes.
Type 1 diabetes; Metabolic syndrome; Dyslipidemia; Cardiovascular risk factor
Elevation of cardiac troponin has been documented in multiple settings without acute coronary syndrome. However, its impact on long-term cardiac outcomes in the context of acute decompensated diabetes remains to be explored.
We performed a retrospective analysis of 872 patients admitted to Temple University Hospital from 2004–2009 with DKA or HHS. Patients were included if they had cardiac troponin I (cTnI) measured within 24 hours of hospital admission, had no evidence of acute coronary syndrome and had a follow up period of at least 18 months. Of the 264 patients who met the criteria, we reviewed the baseline patient characteristics, admission labs, EKGs and major adverse cardiovascular events during the follow up period. Patients were categorized into two groups with normal and elevated levels of cardiac enzymes. The composite end point of the study was the occurrence of a major cardiovascular event (MACE) during the follow up period and was compared between the two groups.
Of 264 patients, 24 patients were found to have elevated cTnI. Compared to patients with normal cardiac enzymes, there was a significant increase in incidence of MACE in patients with elevated cTnI. In a regression analysis, which included prior history of CAD, HTN and ESRD, the only variable that independently predicted MACE was an elevation in cTnI (p = 0.044). Patients with elevated CK-MB had increased lengths of hospitalization compared to the other group (p < 0.001).
Elevated cardiac troponin I in patients admitted with decompensated diabetes and without evidence of acute coronary syndrome, strongly correlate with a later major cardiovascular event. Thus, elevated troponin I during metabolic abnormalities identify a group of patients at an increased risk for poor long-term outcomes. Whether these patients may benefit from early detection, risk stratification and preventive interventions remains to be investigated.
Cardiac troponin-I; Decompensated diabetes; Prognostic markers; Acute coronary syndrome; CK-MB
In diabetes, a variety of pro-inflammatory cellular changes has been found in various cell types, including monocytes which are known to be involved in all the phases of atherogenesis. Angiotensin II (Ang II) type 1 receptor (AT1R) mediates the pro-atherogenic effects of Ang II whereas the type 2 receptor (AT2R) seems associated with atheroprotection. We sought to investigate the potential changes of AT1R-AT2R expression in human monocytes of type 2 diabetic- hypercholesterolemic patients and in hypercholesterolemic subjects, upon clinical treatment with rosuvastatin.
The AT1R membrane protein and mRNA AT1R and AT2R expression in monocytes were investigated in 10 type 2 diabetic-hypercholesterolemic patients and in 10 hypercholesterolemic subjects, before and after 3-month rosuvastatin treatment. Moreover, the serum cytokine levels of interferon-γ (IFN-γ) and interleukin-4 (IL-4) were detected.
As expected, rosuvastatin was associated with a change in the lipid profile in the two groups. Both the membrane protein (P = 0.008) and the AT1R mRNA expression (P = 0.038) were significantly reduced during treatment in the absence of AT2R expression change in diabetic-hypercholesterolemic patients whereas no significant difference was observed in hypercholesterolemic subjects. The serum IL-4 levels were increased during treatment whereas no change was observed in IFN-γ in diabetic-hypercholesterolemic patients. No cytokine change was observed in hypercholesterolemic subjects.
Our study on monocytes of diabetic-hypercholesterolemic patients, showing a reduced AT1R but not AT2R expression during rosuvastatin treatment, suggests that statin therapy may modulate favorably the AT1-AT2 receptor balance in subjects with coexistent type 2 diabetes.
Type 2 Diabetes; Angiotensin II type 1 receptor; Angiotensin II type 2 receptor; Monocytes; Statin
Diabetic patients experience stimulated coagulation and dysfibrinolysis, which is associated with an increased risk of cardiovascular events. This imbalance may precede the manifest diagnosis. We investigated whether elevated antigen levels of tissue plasminogen activator (tPA), plasminogen activator inhibitor-1 (PAI-1), the tPA/PAI-1 complex, or von Willebrand Factor (VWF) precede type 2 diabetes mellitus (T2DM) diagnosis, and whether this elevation occurs before increased fasting plasma glucose (FPG) or 2-hour plasma glucose (2hPG) in individuals who later develop T2DM.
We conducted a prospective incident case-referent study within the Västerbotten Intervention Programme. Cardiovascular risk factor data as well as FPG and 2hPG and blood samples for future research were collected at a baseline health examination between 1989 and 2000, (n= 28 736). During follow-up in January 2001, 157 cases had developed T2DM. Referents without T2DM were matched for sex, age, and year of participation (n=277). Subgroup analysis was performed for cases with normal baseline glucose levels (FPG <6.1 mmol/L and 2hPG < 8.9 mmol/L) and cases with elevated levels (FPG 6.1-6.9 mmol/L and/or 2hPG 8.9-12.1 mmol/L).
After adjusting for BMI, family history of diabetes, physical activity, smoking, systolic blood pressure and levels of C-reactive protein and triglycerides, independent associations were found between incident T2DM and elevated levels of tPA (OR=1.54, 95% CI 1.06-2.23), PAI-1 (OR=1.61, 95% CI 1.14-2.28), and tPA/PAI-1 complex (OR=2.45, 95% CI 1.56-3.84). In participants with normal glucose levels, PAI-1 (OR=2.06, 95% CI 1.10 - 3.86) exhibited an independent relationship with incident T2DM after the adjustments.
Elevated levels of fibrinolytic variables precede the manifestation of T2DM after adjusting for metabolic and cardiovascular risk factors and can be detected several years before changes in glucose tolerance.
Diabetes mellitus type 2; Tissue plasminogen activator; Plasminogen activator inhibitor-1; Von Willebrand factor; Fibrinolysis; Population study; Västerbotten Intervention Programme
Several peptides, named adipokines, are produced by the adipose tissue. Among those, adiponectin (AD) is the most abundant. AD promotes peripheral insulin sensitivity, inhibits liver gluconeogenesis and displays anti-atherogenic and anti-inflammatory properties. Lower levels of AD are related to a higher risk of myocardial infarction and a worse prognosis in patients with coronary artery disease. However, despite a favorable clinical profile, AD increases in relation to worsening heart failure (HF); in this context, higher adiponectinemia is reliably related to poor prognosis. There is still little knowledge about how certain metabolic conditions, such as diabetes mellitus, modulate the relationship between AD and HF.
We evaluated the level of adiponectin in patients with ischemic HF, with and without type 2 diabetes, to elucidate whether the metabolic syndrome was able to influence the relationship between AD and HF.
We demonstrated that AD rises in patients with advanced HF, but to a lesser extent in diabetics than in non-diabetics. Diabetic patients with reduced systolic performance orchestrated a slower rise of AD which began only in face of overt HF. The different behavior of AD in the presence of diabetes was not entirely explained by differences in body mass index. In addition, NT-proBNP, the second strongest predictor of AD, did not differ significantly between diabetic and non-diabetic patients. These data indicate that some other mechanisms are involved in the regulation of AD in patients with type 2 diabetes and coronary artery disease.
AD rises across chronic heart failure stages but this phenomenon is less evident in type 2 diabetic patients. In the presence of diabetes, the progressive increase of AD in relation to the severity of LV dysfunction is hampered and becomes evident only in overt HF.
Adiponectin; Diabetes; Coronary artery disease; Heart failure
Neointimal formation plays an important role in the pathogenesis of coronary restenosis after percutaneous coronary intervention (PCI), especially in patients with diabetes mellitus. Recently, some studies have shown that 5-ethynyl-2'-deoxyuridine (EdU) incorporation can serve as a novel alternative to the 5-bromo-2'-deoxyuridine (BrdU) antibody detection method for detection of DNA synthesis in regenerating avian cochlea, chick embryo and the adult nervous system. However, few studies have been performed to assess the suitability of EdU for detecting DNA synthesis in vascular neointima.
The carotid artery balloon injury model was established in Goto-Kakizaki (GK) and Wistar rats. A Cell-LightTM EdU Kit was used to detect EdU-labeled cell nuclei of common carotid arteries at day 7 after catheter balloon injury. Different methods of injecting EdU were tested. The protein levels of proliferating cell nuclear antigen (PCNA) and p-Akt (Ser473), as well as the mRNA levels of PCNA were evaluated by Western blotting and quantitative real-time PCR (qRT-PCR), respectively. Immunohistochemical staining was also employed to visualize PCNA-positive cells.
At day 7 after catheter balloon injury, far more EdU-positive and PCNA-positive cells were observed in GK rats. When comparing groups that received different EdU doses, it was found that the percentage of EdU-positive cells at a dose of 100 mg/kg body weight was than at doses of 25 mg/kg and 50 mg/kg. The number of positive cells was significantly higher in the repeated injection group compared to the single injection group. Further, after balloon injury DNA synthesis in GK rats was more notable than in Wistar rats. Neointimal formation in GK rats was more obvious than in Wistar rats. The protein levels of PCNA and p-Akt (Ser473) and the mRNA levels of PCNA were increased in injured rats as compared to uninjured rats, and were significantly higher in GK rats than in Wistar rats.
By intraperitoneal injections of EdU at a dose of 100 mg/kg three times, EdU incorporation can detect carotid arterial DNA synthesis caused by neointimal formation in GK rats and Wistar rats at day 7 after balloon injury by the EdU click reaction quickly and effectively. Moreover, more obvious DNA synthesis in the vascular neointima could be observed in GK rats than in Wistar rats.
Neointimal formation; DNA synthesis; Diabetes mellitus; EdU; Catheter balloon injury; PCNA
Low concentrations of plasma vitamin D (25(OH)D) have been associated with the development of metabolic syndrome (MetS), obesity, diabetes and cardiovascular disease. The objective of this study was to quantify the associations between 25(OH)D and parathormone (PTH) plasma levels and obesity, the presence of MetS, diabetes or atherogenic dyslipidemia (AD) in a large sample of individuals with different degrees of adiposity.
Retrospective study of all patients who had attended the obesity clinics in a Spanish hospital between 2009 and 2011, and whose concentrations of PTH, 25(OH)D, calcium and alkaline phosphatase had been determined (n=316, 75.9% women). Individuals were categorized by degree of adiposity, presence of MetS, and other comorbidities.
PTH increased but 25(OH)D and calcium decreased with increasing adiposity. The prevalence of 25(OH)D deficiency or insufficiency increased with obesity (<10% when BMI<45kg/m2, and 26% when >50). The prevalence of hyperparathyroidism increased from 12% in non-obese to 47.5% in morbidly obese individuals with BMI>50 kg/m2. Low plasma 25(OH)D and high PTH concentrations were associated with an increased risk of MetS and AD. These associations disappeared, except in the case of AD for 25(OH)D when adjusting for BMI. Regression analysis revealed that BMI and age or seasonality were independent predictors of PTH and 25(OH)D levels, respectively.
BMI was the variable most strongly associated with plasma 25(OH)D and PTH concentrations in our study. Low 25(OH)D and high PTH concentrations were not independently associated with an increased risk of MetS, or diabetes. Our data support a possible contribution of plasma 25(OH)D to the pathogenesis of hypertriglyceridemia and AD through inflammation.
Obesity; Metabolic syndrome; Vitamin D; Parathormone
Endothelial progenitor cells (EPCs) are responsible for angiogenesis and maintenance of microvascular integrity, the number of EPCs is correlated with oxidative stress. Their relation to myocardial dysfunction in patients with type 2 diabetes mellitus (T2DM) is nonetheless unknown.
Eighty-seven patients with T2DM and no history of coronary artery disease were recruited. Transthoracic echocardiography and detailed evaluation of left ventricular (LV) systolic function by 2-dimensional (2D) speckle tracking derived strain analysis in 3 orthogonal directions was performed. Four subpopulations of EPCs, including CD34+, CD133+, CD34+/kinase insert domain-containing receptor (KDR) + and CD133+/KDR + EPCs, were measured by flow cytometry. Oxidative stress was assessed by superoxide dismutase (SOD).
The mean age of the patients was 62 ± 9 years and 39.6% were male. Those with an impaired longitudinal strain had a lower number of CD34+ EPCs (2.82 ± 1.87% vs. 3.74 ± 2.12%, P < 0.05) than those with preserved longitudinal strain. When compared with those with preserved circumferential strain, patients with an impaired circumferential strain had a lower number of CD34+ EPCs (2.63 ± 1.80% vs. 3.87 ± 2.10%, P < 0.01) and SOD level (0.13 ± 0.06U/ml vs. 0.20 ± 0.08U/ml, P < 0.01). Patients with an impaired radial strain nonetheless had a lower number of CD34+ EPCs (2.62 ± 2.08% vs. 3.69 ± 1.99%, P < 0.05). Multivariate analysis demonstrated that only impaired global circumferential strain remained significantly associated with CD34 + EPCs and SOD.
LV global circumferential strain was independently associated with number of CD34+ EPCs and SOD. These findings suggest that myocardial dysfunction in patients with T2DM is related to depletion of EPCs and increased oxidative stress.
Type 2 diabetes mellitus; Myocardial injury; Endothelial progenitor cells
Patients with type 2 diabetes have 2–4 times greater risk for cardiovascular morbidity and mortality than those without, and this is even further aggravated if they also suffer from hypertension. Unfortunately, less than one third of hypertensive diabetic patients meet blood pressure targets, and more than half fail to achieve target HbA1c values. Thus, appropriate blood pressure and glucose control are of utmost importance. Since treatment sometimes fails in clinical practice while clinical trials generally suggest good efficacy, data from daily clinical practice, especially with regard to the use of newly developed anti-diabetic and anti-hypertensive compounds in unselected patient populations, are essential. The DIALOGUE registry aims to close this important gap by evaluating different treatment approaches in hypertensive type 2 diabetic patients with respect to their effectiveness and tolerability and their impact on outcomes. In addition, DIALOGUE is the first registry to determine treatment success based on the new individualized treatment targets recommended by the ADA and the EASD.
DIALOGUE is a prospective observational German multicentre registry and will enrol 10,000 patients with both diabetes and hypertension in up to 700 sites. After a baseline visit, further documentations are scheduled at 6, 12 and 24 months. There are two co-primary objectives referring to the most recent guidelines for the treatment of diabetes and hypertension: 1) individual HbA1c goal achievement with respect to anti-diabetic pharmacotherapy and 2) individual blood pressure goal achievement with different antihypertensive treatments. Among the secondary objectives the rate of major cardio-vascular and cerebro-vascular events (MACCE) and the rate of hospitalizations are the most important.
The registry will be able to gain insights into the reasons for the obvious gap between the demonstrated efficacy and safety of anti-diabetic and anti-hypertensive drugs in clinical trials and their real world balance of effectiveness and safety.
Type-2 diabetes; Hypertension; Efficacy; Effectiveness; Safety; Vildagliptin
The purpose of this study was to determine the sex-specific pattern of pediatric cardiometabolic risk with principal component analysis, using several biological, behavioral and parental variables in a large cohort (n = 2866) of 6th grade students.
Cardiometabolic risk components included waist circumference, fasting glucose, blood pressure, plasma triglycerides levels and HDL-cholesterol. Principal components analysis was used to determine the pattern of risk clustering and to derive a continuous aggregate score (MetScore). Stratified risk components and MetScore were analyzed for association with age, body mass index (BMI), cardiorespiratory fitness (CRF), physical activity (PA), and parental factors.
In both boys and girls, BMI and CRF were associated with multiple risk components, and overall MetScore. Maternal smoking was associated with multiple risk components in girls and boys, as well as MetScore in boys, even after controlling for children’s BMI. Paternal family history of early cardiovascular disease (CVD) and parental age were associated with increased blood pressure and MetScore for girls. Children’s PA levels, maternal history of early CVD, and paternal BMI were also indicative for various risk components, but not MetScore.
Several biological and behavioral factors were independently associated with children’s cardiometabolic disease risk, and thus represent a unique gender-specific risk profile. These data serve to bolster the independent contribution of CRF, PA, and family-oriented healthy lifestyles for improving children’s health.
Pediatrics; Principal component analysis; Cardiorespiratory fitness; Obesity
Patients with type 1 diabetes have a substantial risk of developing cardiovascular complications early in life. We aimed to explore the role of insulin sensitivity (Si) as an early factor of atherosclerosis in young type 1 diabetes vs. non-diabetic subjects.
Forty adolescent and young adult individuals (20 type 1 diabetics and 20 non-diabetics), age 14–20 years, without characteristics of the metabolic syndrome, participated in this cross-sectional study. After an overnight fast, Si was measured by hyperinsulinemic euglycemic clamp (40 mU/m2) and calculated by glucose infusion rate (GIR). Carotid intima-media thickness (cIMT) was measured in the common carotid artery with high-resolution ultrasonography. Risk factors of atherosclerosis (Body mass index [BMI], waist circumference, systolic blood pressure [sBP], triglycerides, low HDL-cholesterol and HbA1c) were also investigated.
cIMT was increased (0.52 ± 0.1 vs. 0.47 ± 0.1 mm, P < 0.01), whereas GIR was decreased (5.0 ± 2.1 vs. 7.1 ± 2.2 mg/kg/min, P < 0.01) in type 1 diabetics vs. non-diabetics. The differences in cIMT were negatively associated with Si (r = −0.4, P < 0.01) and positively associated with waist circumference (r = 0.34, P = 0.03), with no such associations between BMI (r = 0.15, P = 0.32), sBP (r = 0.09, P = 0.58), triglycerides (r = 0.07, P = 0.66), HDL-cholesterol (r = 0.10, P = 0.55) and HbA1c (r = 0.24, P = 0.13). In a multivariate regression model, between cIMT (dependent) and group (explanatory), only adjustment for Si affected the significance (ß = 0.08, P = 0.11) vs. (ß = 0.07, P < 0.01) for the whole model. No interaction between cIMT, groups and Si was observed.
cIMT is increased and associated with insulin resistance in adolescent, non-obese type 1 diabetic subjects. Although, no conclusions toward a causal relationship can be drawn from current findings, insulin resistance emerges as an important factor reflecting early signs of atherosclerosis in this small cohort.
Adolescent; Atherosclerosis; Carotid intima-media thickness; Insulin sensitivity; Type 1 diabetes
Endothelial dysfunction is a well documented evidence for the onset of atherosclerosis and other cardiovascular diseases. Lipids disorder is among the main risk factors for endothelial dysfunction in these diseases. Steroidogenic acute regulatory protein (StAR), one of the cholesterol transporters, plays an important role in the maintenance of intracellular lipid homeostasis. However, the effect of StAR on endothelial dysfunction is not well understood. Palmitic acid (PA) has been shown to decrease eNOS activity and induce inflammation, both are the causes of endothelial dysfunction, in an endothelial cell culture model.
StAR gene was introduced into primary rat aortic endothelial cells by adenovirus infection. Real-time PCR and Western blotting were performed to determine the relative genes and proteins expression level to elucidate the underlying mechanism. The free fatty acid and cholesterol quantification kits were used to detect total cellular free fatty acid and cholesterol. The levels of inflammatory factors and nitric oxide were determined by ELISA and classic Griess reagent methods respectively.
We successfully overexpressed StAR in primary rat aortic endothelial cells. Following StAR overexpression, mRNA levels of IL-1β, TNFα, IL6 and VCAM-1 and protein levels of IL-1β, , TNFα and IL-6 in culture supernatant were significantly decreased, which duing to blocke NFκB nuclear translocation and activation. Moreover, StAR overexpression attenuated the PA-induced reduction of nitric oxide bioavailability by protecting the bioactivity of pAkt/peNOS/NO pathway. Furthermore, the key genes involved in lipid metabolism were greatly reduced following StAR overexpression. In order to investigate the underlying mechanism, cerulenin and lovastatin, the inhibitor of fatty acid and cholesterol synthase, were added prior to PA treatment. The results showed that both cerulenin and lovastatin had a similar effect as StAR overexpression. On the other hand, the role of StAR was inhibited when siRNA was introduced to reduce StAR expression.
Our results showed that StAR attenuated lipid synthesis and uptake as well as PA-induced inflammation and reduction in NO bioavailability in aortic endothelial cells. StAR can ameliorate endothelial dysfunction induced by PA via reducing the intracellular lipid levels.
Steroidogenic acute regulatory protein; Endothelial dysfunction; Palmitic acid; Inflammation; Lipid metabolism; Nitric oxide
The role of systemic and myocardial adiponectin (ADN) in dilated cardiomyopathy is still debated. We tested the regulation of both systemic and myocardial ADN and the relationship with AMP-activated protein kinase (AMPK) activity in a swine model of non-ischemic dilated cardiomyopathy.
Methods and results
Cardiac tissue was collected from seven instrumented adult male minipigs by pacing the left ventricular (LV) free wall (180 beats/min, 3 weeks), both from pacing (PS) and opposite sites (OS), and from five controls. Circulating ADN levels were inversely related to global and regional cardiac function. Myocardial ADN in PS was down-regulated compared to control (p < 0.05), yet ADN receptor 1 was significantly up-regulated (p < 0.05). No modifications of AMPK were observed in either region of the failing heart. Similarly, myocardial mRNA levels of PPARγ, PPARα, TNFα, iNOS were unchanged compared to controls.
Paradoxically, circulating ADN did not show any cardioprotective effect, confirming its role as negative prognostic biomarker of heart failure. Myocardial ADN was reduced in PS compared to control in an AMPK-independent fashion, suggesting the occurrence of novel mechanisms by which reduced cardiac ADN levels may regionally mediate the decline of cardiac function.
Adiponectin receptors; Heart failure; Animal models; AMPK; Adiponectin
Central arterial stiffness represents a well-established predictor of cardiovascular disease. Decreased circulating endothelial progenitor cells (EPCs), increased asymmetric dimethyl-arginine (ADMA) levels, traditional cardiovascular risk factors and insulin resistance have all been associated with increased arterial stiffness. The correlations of novel and traditional cardiovascular risk factors with central arterial stiffness in prediabetic individuals were investigated in the present study.
The study population consisted of 53 prediabetic individuals. Individuals were divided into groups of isolated impaired fasting glucose (IFG), isolated impaired glucose tolerance (IGT) and combined IGT-IFG. Age, sex, family history of diabetes, smoking history, body mass index (BMI), waist to hip ratio (WHR), waist circumference (WC), blood pressure, lipid profile, levels of high sensitive C-reactive protein (hsCRP), glomerular filtration rate (GFR), and history of antihypertensive or statin therapy were obtained from all participants. Insulin resistance was evaluated using the Homeostatic Model Assessment (HOMA-IR). Carotid -femoral pulse wave velocity was used as an index of arterial stiffness. Circulating EPC count and ADMA serum levels were also determined.
Among studied individuals 30 (56.6%) subjects were diagnosed with isolated IFG, 9 (17%) with isolated IGT (17%) and 14 with combined IFG-IGT (26.4%). In univariate analysis age, mean blood pressure, fasting glucose, total cholesterol, LDL cholesterol, and ADMA levels positively correlated with pulse-wave velocity while exercise and GFR correlated negatively. EPC count did not correlate with PWV. In multivariate stepwise regression analysis PWV correlated independently and positively with LDL-Cholesterol (low density lipoprotein) and ADMA levels and negatively with exercise.
Elevated ADMA and LDL-C levels are strongly associated with increased arterial stiffness among pre-diabetic subjects. In contrast exercise inversely correlated with arterial stiffness.
Pre-diabetes; ADMA; Pulse wave velocity; Endothelial progenitor cells
To assess the efficacy and safety of adding liraglutide to established insulin therapy in poorly controlled Chinese subjects with type 2 diabetes and abdominal obesity compared with increasing insulin dose.
A 12-week, randomized, parallel-group study was carried out. A total of 84 patients completed the trial who had been randomly assigned to either the liraglutide-added group or the insulin-increasing group while continuing current insulin based treatment. Insulin dose was reduced by 0-30% upon the initiation of liraglutide. Insulin doses were subsequently adjusted to optimized glycemic control. Glycosylated hemoglobin (HbA1c) values, blood glucose, total daily insulin dose, body weight, waist circumference, and the number of hypoglycemic events and adverse events were evaluated.
At the end of study, the mean reduction in HbA1c between the liraglutide-added group and the insulin-increasing group was not significantly different (1.9% vs. 1.77%, p>0.05). However, the percentage of subjects reaching the composite endpoint of HbA1c ≤ 7.0% with no weight gain and no hypoglycemia, was significantly higher in the liraglutide-added group than in the insulin-increasing group (67% vs. 19%, p<0.001). Add-on liraglutide treatment significantly reduced mean body weight (5.62 kg, p<0.01), waist circumference (5.70 cm, p<0.01), body mass index (BMI) (1.93 kg/m2, p<0.01) and daily total insulin dose (dropped by 66%) during 12-week treatment period, while all of these significantly increased with insulin increasing treatment. Add-on liraglutide treated patients had lower rate of hypoglycemic events and greater insulin and oral antidiabetic drugs discontinuation. Gastrointestinal disorders were the most common adverse events in the liraglutide added treatment, but were transient.
Addition of liraglutide to abdominally obese, insulin-treated patients led to improvement in glycemic control similar to that achieved by increasing insulin dosage, but with a lower daily dose of insulin and fewer hypoglycemic events. Adding liraglutide to insulin also induced a significant reduction in body weight and waist circumference. Liraglutide combined with insulin may be the best treatment option for poorly controlled type 2 diabetes and abdominal obesity.
Liraglutide; Abdominal obesity; Insulin therapy; Weight reduction
All fibrates are peroxisome proliferators-activated receptors (PPARs)-alpha agonists with ability to decrease triglyceride and increase high density lipoprotein- cholesterol (HDL-C). However, bezafibrate has a unique characteristic profile of action since it activates all three PPAR subtypes (alpha, gamma and delta) at comparable doses. Therefore, bezafibrate operates as a pan-agonist for all three PPAR isoforms. Selective PPAR gamma agonists (thiazolidinediones) are used to treat type 2 diabetes mellitus (T2DM). They improve insulin sensitivity by up-regulating adipogenesis, decreasing free fatty acid levels, and reversing insulin resistance. However, selective PPAR gamma agonists also cause water retention, weight gain, peripheral edema, and congestive heart failure. The expression of PPAR beta/ delta in essentially all cell types and tissues (ubiquitous presence) suggests its potential fundamental role in cellular biology. PPAR beta/ delta effects correlated with enhancement of fatty acid oxidation, energy consumption and adaptive thermogenesis. Together, these data implicate PPAR beta/delta in fuel combustion and suggest that pan-PPAR agonists that include a component of PPAR beta/delta activation might offset some of the weight gain issues seen with selective PPAR gamma agonists, as was demonstrated by bezafibrate studies. Suggestively, on the whole body level all PPARs acting as one orchestra and balanced pan-PPAR activation seems as an especially attractive pharmacological goal. Conceptually, combined PPAR gamma and alpha action can target simultaneously insulin resistance and atherogenic dyslipidemia, whereas PPAR beta/delta properties may prevent the development of overweight. Bezafibrate, as all fibrates, significantly reduced plasma triglycerides and increased HDL-C level (but considerably stronger than other major fibrates). Bezafibrate significantly decreased prevalence of small, dense low density lipoproteins particles, remnants, induced atherosclerotic plaque regression in thoracic and abdominal aorta and improved endothelial function. In addition, bezafibrate has important fibrinogen-related properties and anti-inflammatory effects. In clinical trials bezafibrate was highly effective for cardiovascular risk reduction in patients with metabolic syndrome and atherogenic dyslipidemia. The principal differences between bezafibrate and other fibrates are related to effects on glucose level and insulin resistance. Bezafibrate decreases blood glucose level, HbA1C, insulin resistance and reduces the incidence of T2DM compared to placebo or other fibrates. Currently statins are the cornerstone of the treatment and prevention of cardiovascular diseases related to atherosclerosis. However, despite the increasing use of statins as monotherapy for low density lipoprotein- cholesterol (LDL-C) reduction, a significant residual cardiovascular risk is still presented in patients with atherogenic dyslipidemia and insulin resistance, which is typical for T2DM and metabolic syndrome. Recently, concerns were raised regarding the development of diabetes in statin-treated patients. Combined bezafibrate/statin therapy is more effective in achieving a comprehensive lipid control and residual cardiovascular risk reduction. Based on the beneficial effects of pan-PPAR agonist bezafibrate on glucose metabolism and prevention of new-onset diabetes, one could expect a neutralization of the adverse pro-diabetic effect of statins using the strategy of a combined statin/fibrate therapy.
Atherogenic dyslipidemia; Bezafibrate; Combined fibrate/statin therapy; Metabolic syndrome; PPAR; Prevention; Residual cardiovascular risk; Type 2 diabetes
Telmisartan is a well-established angiotensin II type 1 receptor blocker that improves insulin sensitivity in animal models of obesity and insulin resistance, as well as in humans. Telmisartan has been reported to function as a partial agonist of the peroxisome proliferator-activated receptor (PPAR) γ, which is also targeted by the nicotinamide adenine dinucleotide (NAD)-dependent deacetylase (SIRT1). Here, we investigated the pathways through which telmisartan acts on skeletal muscle, in vitro as well as in vivo.
Nine-week-old male db/db mice were fed a 60% high-fat diet, with orally administrated either vehicle (carboxymethyl-cellulose, CMC), 5 mg/kg telmisartan, or 5 mg/kg telmisartan and 1 mg/kg GW9662, a selective irreversible antagonist of PPARγ, for 5 weeks. Effects of telmisartan on Sirt1 mRNA, AMPK phosphorylation, and NAD+/NADH ratio were determined in C2C12 cultured myocytes.
Results and discussion
Telmisartan treatment improved insulin sensitivity in obese db/db mice fed a high-fat diet and led to reduction in the size of hypertrophic pancreatic islets in these mice. Moreover, in vitro treatment with telmisartan led to increased expression of Sirt1 mRNA in C2C12 skeletal muscle cells; the increase in Sirt1 mRNA in telmisartan-treated C2C12 myoblasts occurred concomitantly with an increase in AMPK phosphorylation, an increase in NAD+/NADH ratio, and increases in the mRNA levels of PGC1α, FATP1, ACO, and GLUT4.
Our results indicate that telmisartan acts through a PPARγ-independent pathway, but at least partially exerts its effects by acting directly on skeletal muscle AMPK/SIRT1 pathways.
Adiponectin; AMP-activated protein kinase; Obesity; Peroxisome proliferator-activated receptor-γ; SIRT1
The genomic region at 9p21 chromosome near the CDKN2A/CDKN2B genes is associated with type 2 diabetes(T2D) and cardiovascular disease(CVD). The effect of the 9p21 locus on long-term mortality in patients with T2D has yet to be determined.
We examined three single nucleotide polymorphisms (SNPs) on 9p21, consistently and independently associated with T2D (rs10811661) or CVD (rs10757278, rs2383206), in relation to the risk of total and cardiovascular mortality in diabetic patients. We also aimed to replicate the previously observed interaction between rs2383206 and glycemic control on mortality.
Genotypes for three SNPs were determined in 914 individuals from a prospective cohort of T2D patients of Dutch origin. Associations with mortality were assessed using Cox proportional hazard analyses.
After a median follow-up of 9.5 years, 358 out of 914 patients had died. The hazard ratio (HR) for total mortality among individuals homozygous for the T2D-risk allele of rs10811661 compared to non-homozygous individuals was 0.74(95%CI 0.59-0.93). For the carriers of both CVD-risk alleles of rs10757278, the HR for total mortality was 1.31(95%CI 1.01-1.70). We found a significant interaction between rs2383206 and HbA1c on mortality, which was higher among patients with two CVD-risk alleles in the two lowest HbA1c tertiles (HR 1.68(95%CI 1.08-2.63); HR 1.48(95%CI 1.01-2.18).
In conclusion, common variants on 9p21 were associated with mortality in patients with T2D in a Dutch population. The T2D SNP was inversely associated with mortality, while the CVD SNP increased the risk for mortality. We confirmed a possible, although different, synergistic relationship between HbA1c and rs2383206 on total mortality.
Type 2 Diabetes; CVD; Mortality; 9p21; Genetics; SNP
Although the Fat Mass and Obesity (FTO) and Melanocortin-4 Receptor (MC4R) genes have been consistently associated with obesity risk, the association between the obesity-risk alleles with type 2 diabetes is still controversial. In some recent meta-analyses in which significant results have been reported, the associations disappeared after adjustment for body mass index (BMI). However gene-diet interactions with dietary patterns have not been investigated. Our main aim was to analyze whether these associations are modulated by the level of adherence to the Mediterranean Diet (MedDiet).
Case-control study in 7,052 high cardiovascular risk subjects (3,430 type 2 diabetes cases and 3,622 non-diabetic subjects) with no differences in BMI. Diet was assessed by validated questionnaires. FTO-rs9939609 and MC4R-rs17782313 were determined. An aggregate genetic score was calculated to test additive effects. Gene-diet interactions were analyzed.
Neither of the polymorphisms was associated with type 2 diabetes in the whole population. However, we found consistent gene-diet interactions with adherence to the MedDiet both for the FTO-rs9939609 (P-interaction=0.039), the MC4R-rs17782313 (P-interaction=0.009) and for their aggregate score (P-interaction=0.006). When adherence to the MedDiet was low, carriers of the variant alleles had higher type 2 diabetes risk (OR=1.21, 95%CI: 1.03-1.40; P=0.019 for FTO-rs9939609 and OR=1.17, 95%CI:1.01-1.36; P=0.035 for MC4R-rs17782313) than wild-type subjects. However, when adherence to the MedDiet was high, these associations disappeared (OR=0.97, 95%CI: 0.85-1.16; P=0.673 for FTO-rs9939609 and OR=0.89, 95%CI:0.78-1.02; P=0.097 for MC4R-rs17782313). These gene-diet interactions remained significant even after adjustment for BMI. As MedDiet is rich in folate, we also specifically examined folate intake and detected statistically significant interaction effects on fasting plasma glucose concentrations in non-diabetic subjects. However these findings should be interpreted with caution because folate intake may simply reflect a healthy dietary pattern.
These novel results suggest that the association of the FTO-rs9939609 and the MC4R-rs17782313 polymorphisms with type 2 diabetes depends on diet and that a high adherence to the MedDiet counteracts the genetic predisposition.
Nutrigenetics; Mediterranean diet; Diabetes; FTO; MC4R; Gene-diet interactions
To assess associations between body size and blood pressure in children (5-6 years) from different ethnic origins.
Five ethnic groups of the ABCD cohort were examined: Dutch (n=1 923), Turkish (n=99), Moroccan (n=187), Black-African (n=67) and Black-Caribbean (n=121). Data on body-mass-index (BMI), waist-to-height ratio (WHtR), fat-mass-index (FMI), and systolic blood pressure (SBP) and diastolic blood pressure (DBP), were collected. Linear regression analysis with restricted cubic splines was used to examine non-linear associations between body size and blood pressure, adjusted for age, sex, height and birth weight.
Ethnic differences were found in associations of BMI with SBP and DBP (SBP: p=0.001 and DBP: p=0.01) and FMI with SBP (p=0.03). BMI and FMI had a relatively large positive association with SBP in Turkish children (BMI: β=2.46mmHg; 95%CI:1.20-3.72; FMI: β=2.41mmHg; 95%CI:1.09-3.73) compared to Dutch (BMI: β=1.31mmHg; 95%CI:0.71-1.92; FMI: β=0.84mmHg; 95%CI:0.23-1.45). Black-Caribbean and Moroccan children showed high blood pressure with low BMI and FMI. Moroccan children showed higher SBP with high BMI and FMI. WHtR was positively associated with SBP and DBP, similar in all ethnic groups. Generally, strongest associations with blood pressure were found for BMI in all ethnic groups.
Ethnic-specific associations between BMI, and FMI and blood pressure are present at young age, with Turkish children showing the highest increase in blood pressure with increasing body size. The higher blood pressure in the Black-Caribbean and Moroccan children with low BMI needs further research. WHtR or FMI do not seem to be associated more strongly to blood pressure than BMI in any ethnic group.
Blood pressure; Ethnicity; Children; Adiposity; Body size
It has been reported previously that diabetic cardiomyopathy can be inhibited or reverted with chronic zinc supplementation. In the current study, we hypothesized that total cardiac calcium and zinc content is altered in early onset diabetes mellitus characterized in part as hyperglycemia (HG) and that exposure of zinc ion (Zn2+) to isolated cardiomyocytes would enhance contraction-relaxation function in HG more so than in nonHG controls. To better control for differential cardiac myosin isoform expression as occurs in rodents after β-islet cell necrosis, hypothyroidism was induced in 16 rats resulting in 100% β-myosin heavy chain expression in the heart. β-Islet cell necrosis was induced in half of the rats by streptozocin administration. After 6 wks of HG, both HG and nonHG controls rats demonstrated similar myofilament performance measured as thin filament calcium sensitivity, native thin filament velocity in the myosin motility assay and contractile velocity and power. Extracellular Zn2+ reduced cardiomyocyte contractile function in both groups, but enhanced relaxation function significantly in the HG group compared to controls. Most notably, a reduction in diastolic sarcomere length with increasing pacing frequencies, i.e., incomplete relaxation, was more pronounced in the HG compared to controls, but was normalized with extracellular Zn2+ application. This is a novel finding implicating that the detrimental effect of HG on cardiomyocyte Ca2+ regulation can be amelioration by Zn2+. Among the many post-translational modifications examined, only phosphorylation of ryanodine receptor (RyR) at S-2808 was significantly higher in HG compared to nonHG. We did not find in our hypothyroid rats any differentiating effects of HG on myofibrillar protein phosphorylation, lysine acetylation, O-linked N-acetylglucosamine and advanced glycated end-products, which are often implicated as complicating factors in cardiac performance due to HG. Our results suggest that the relaxing effects of Zn2+ on cardiomyocyte function are more pronounced in the HG state due an insulin-dependent effect of enhancing removal of cytosolic Ca2+ via SERCA2a or NCX or by reducing Ca2+ influx via L-type channel or Ca2+ leak through the RyR. Investigations into the effects of Zn2+ on these mechanisms are now underway.
Streptozotocin; PTU; Type 1 diabetes; Cardiac; Iron; Sulfur
Patients with hypertension and cardiovascular disease (CVD), diabetes, or chronic kidney disease (CKD) usually require two or more antihypertensive agents to achieve blood pressure (BP) goals.
The efficacy/safety of olmesartan (OM) 40 mg, amlodipine besylate (AML) 10 mg, and hydrochlorothiazide (HCTZ) 25 mg versus the component dual-combinations (OM 40/AML 10 mg, OM 40/HCTZ 25 mg, and AML 10/HCTZ 25 mg) was evaluated in participants with diabetes, CKD, or chronic CVD in the Triple Therapy with Olmesartan Medoxomil, Amlodipine, and Hydrochlorothiazide in Hypertensive Patients Study (TRINITY). The primary efficacy end point was least squares (LS) mean reduction from baseline in seated diastolic BP (SeDBP) at week 12. Secondary end points included LS mean reduction in SeSBP and proportion of participants achieving BP goal (<130/80 mm Hg) at week 12 (double-blind randomized period), and LS mean reduction in SeBP and BP goal achievement at week 52/early termination (open-label period).
At week 12, OM 40/AML 10/HCTZ 25 mg resulted in significantly greater SeBP reductions in participants with diabetes (−37.9/22.0 mm Hg vs −28.0/17.6 mm Hg for OM 40/AML 10 mg, −26.4/14.7 mm Hg for OM 40/HCTZ 25 mg, and −27.6/14.8 mm Hg for AML 10/HCTZ 25 mg), CKD (−44.3/25.5 mm Hg vs −39.5/23.8 mm Hg for OM 40/AML 10 mg, −25.3/17.0 mm Hg for OM 40/HCTZ 25 mg, and −33.4/20.6 mm Hg for AML 10/HCTZ 25 mg), and chronic CVD (−37.8/20.6 mm Hg vs −31.7/18.2 mm Hg for OM 40/AML 10 mg, −30.9/17.1 mm Hg for OM 40/HCTZ 25 mg, and −27.5/16.1 mm Hg for AML 10/HCTZ 25 mg) (P<0.05 for all subgroups vs dual-component treatments). BP goal achievement was greater for participants receiving triple-combination treatment compared with the dual-combination treatments, and was achieved in 41.1%, 55.0%, and 38.9% of participants with diabetes, CKD, and chronic CVD on OM 40/AML 10/HCTZ 25 mg, respectively. At week 52, there was sustained BP lowering with the OM/AML/HCTZ regimen. Overall, the triple combination was well tolerated.
In patients with diabetes, CKD, or chronic CVD, short-term (12 weeks) and long-term treatment with OM 40/AML 10/HCTZ 25 mg was well tolerated, lowered BP more effectively, and enabled more participants to reach BP goal than the corresponding 2-component regimens.
Trial Identification Number
Hypertension; Diabetes mellitus; Chronic kidney disease; Cardiovascular diseases; Drug combinations
Mechanisms involved in metabolic syndrome (MetS) development include insulin resistance, weight regulation, inflammation and lipid metabolism. Aim of this study is to investigate the association of single nucleotide polymorphisms (SNPs) involved in these mechanisms with MetS.
In a random sample of the EPIC-NL study (n = 1886), 38 SNPs associated with waist circumference, insulin resistance, triglycerides, HDL cholesterol and inflammation in genome wide association studies (GWAS) were selected from the 50K IBC array and one additional SNP was measured with KASPar chemistry. The five groups of SNPs, each belonging to one of the metabolic endpoints mentioned above, were associated with MetS and MetS-score using Goeman’s global test. For groups of SNPs significantly associated with the presence of MetS or MetS-score, further analyses were conducted.
The group of waist circumference SNPs was associated with waist circumference (P=0.03) and presence of MetS (P=0.03). Furthermore, the group of SNPs related to insulin resistance was associated with MetS score (P<0.01), HDL cholesterol (P<0.01), triglycerides (P<0.01) and HbA1C (P=0.04). Subsequent analyses showed that MC4R rs17782312, involved in weight regulation, and IRS1 rs2943634, related to insulin resistance were associated with MetS (OR 1.16, 95%CI 1.02-1.32 and OR 0.88, 95% CI 0.79; 0.97, respectively). The groups of inflammation and lipid SNPs were neither associated with presence of MetS nor with MetS score.
In this study we found support for the hypothesis that weight regulation and insulin metabolism are involved in MetS development.MC4R rs17782312 and IRS1 rs2943634 may explain part of the genetic variation in MetS.
Metabolic syndrome; Genetics; MC4R; IRS1
Chronic obstructive pulmonary disease, metabolic syndrome and diabetes mellitus are common and underdiagnosed medical conditions. It was predicted that chronic obstructive pulmonary disease will be the third leading cause of death worldwide by 2020. The healthcare burden of this disease is even greater if we consider the significant impact of chronic obstructive pulmonary disease on the cardiovascular morbidity and mortality.
Chronic obstructive pulmonary disease may be considered as a novel risk factor for new onset type 2 diabetes mellitus via multiple pathophysiological alterations such as: inflammation and oxidative stress, insulin resistance, weight gain and alterations in metabolism of adipokines.
On the other hand, diabetes may act as an independent factor, negatively affecting pulmonary structure and function. Diabetes is associated with an increased risk of pulmonary infections, disease exacerbations and worsened COPD outcomes. On the top of that, coexistent OSA may increase the risk for type 2 DM in some individuals.
The current scientific data necessitate a greater outlook on chronic obstructive pulmonary disease and chronic obstructive pulmonary disease may be viewed as a risk factor for the new onset type 2 diabetes mellitus. Conversely, both types of diabetes mellitus should be viewed as strong contributing factors for the development of obstructive lung disease. Such approach can potentially improve the outcomes and medical control for both conditions, and, thus, decrease the healthcare burden of these major medical problems.
COPD; Dysglycemia; Insulin resistance; Obesity; Metabolic syndrome; Diabetes mellitus endothelial dysfunction; Vasculopathy