Search

Objective: To assess whether the presence of microvascular complications modifies the effect of intensive glucose reduction on long-term outcomes in patients with type 2 diabetes., Patients and Methods: Using ACCORD and ACCORDION study data, we investigated the risk of the primary outcome (nonfatal myocardial infarction, nonfatal stroke, or cardiovascular death) or death in relation to the prerandomization type and extent of microvascular complications. Interaction terms were fitted in survival models to estimate the risk of both outcomes across levels of an overall microvascular disease score (range 0 to 100) and its individual components: diabetic nephropathy, retinopathy, and neuropathy., Results: During a mean follow-up of 7.7 years, 1685 primary outcomes and 1806 deaths occurred in 9405 participants. The outcome-specific microvascular score was ≤30 in 97.9% of subjects for the primary outcome and in 98.5% for death. For participants with scores of 0 and 30, respectively, the 10-year absolute risk difference between intensive glucose control and standard treatment ranged from -0.8% (95% CI, -2.6, 1.1) to -3.0% -7.1, 1.1) for the primary outcome and from -0.5% (-2.1, 1.1) to 0.7% (-4.2, 5.6) for mortality. Retinopathy was associated with the largest effects, with a 10-year absolute risk difference of -6.5% (-11.1 to -2.0) for the primary outcome and -3.9% (-7.8 to 0.1) for mortality., Conclusion: This hypothesis-generating study identifies diabetic retinopathy as predictor of the beneficial effect of intensive glucose control on the risk of cardiovascular disease and possibly death. Further long-term studies are required to confirm these findings., (Copyright © 2020 Mayo Foundation for Medical Education and Research. Published by Elsevier Inc. All rights reserved.)

Background: Peripheral artery disease (PAD) represents one of the most relevant vascular complications of type 2 diabetes mellitus (T2DM). Moreover, T2DM patients suffering from PAD have an increased risk of major adverse cardiovascular events (MACE) and major adverse limb events (MALE). Sortilin, a protein involved in apolipoproteins trafficking, is associated with lower limb PAD in T2DM patients., Objective: To evaluate the relationship between baseline serum levels of sortilin, MACE and MALE occurrence after revascularization of T2DM patients with PAD and chronic limb-threatening ischemia (CLTI)., Research Design and Methods: We performed a prospective non-randomized study including 230 statin-free T2DM patients with PAD and CLTI. Sortilin levels were measured before the endovascular intervention and incident outcomes were assessed during a 12 month follow-up., Results: Sortilin levels were significantly increased in individuals with more aggressive PAD (2.25 ± 0.51 ng/mL vs 1.44 ± 0.47 ng/mL, p < 0.001). During follow-up, 83 MACE and 116 MALE occurred. In patients, who then developed MACE and MALE, sortilin was higher. In particular, 2.46 ± 0.53 ng/mL vs 1.55 ± 0.42 ng/mL, p < 0.001 for MACE and 2.10 ± 0.54 ng/mL vs 1.65 ± 0.65 ng/mL, p < 0.001 for MALE. After adjusting for traditional atherosclerosis risk factors, the association between sortilin and vascular outcomes remained significant in a multivariate analysis. In our receiver operating characteristics (ROC) curve analysis using sortilin levels the prediction of MACE incidence improved (area under the curve [AUC] = 0.94) and MALE (AUC = 0.72)., Conclusions: This study demonstrates that sortilin correlates with incidence of MACE and MALE after endovascular revascularization in a diabetic population with PAD and CLTI.

Objective: Peripheral artery disease (PAD) is one of the most relevant complications of diabetes. Although several pharmacological and revascularization approaches are available for treating patients with diabetes and PAD, an endovascular approach is often associated with postprocedural complications that can increase the risk for acute limb ischemia or amputation. However, no definitive molecular associations have been described that could explain the difference in outcomes after endovascular treatment in patients with diabetes, PAD, and chronic limb-threatening ischemia (CLTI)., Research Design and Methods: We evaluated the relationship between the levels of the main cytokines associated with diabetic atherosclerosis and the outcomes after endovascular procedures in patients with diabetes, PAD, and CLTI., Results: A total of 299 patients with below-the-knee occlusive disease who were undergoing an angioplasty procedure were enrolled. The levels of key cytokines-osteoprotegerin (OPG), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and C-reactive protein (CRP)-were measured, and major adverse limb events (MALE) and major adverse cardiovascular events (MACE) were assessed 1, 3, 6, and 12 months after the procedure. There was a linear trend from the lowest to the highest quartile for each cytokine at baseline and incident MALE. A linear association was also observed between increasing levels of each cytokine and incident MACE. Receiver operating characteristics models were constructed using clinical and laboratory risk factors, and the inclusion of cytokines significantly improved the prediction of incident events., Conclusions: We demonstrated that elevated OPG, TNF-α, IL-6, and CRP levels at baseline correlate with worse vascular outcomes in patients with diabetes, PAD, and CLTI undergoing an endovascular procedure., (© 2019 by the American Diabetes Association.)

Background: Type-2 diabetes mellitus is one of the major risk factors of atherosclerosis, particularly in peripheral artery disease (PAD). Several studies have documented a correlation between omentin-1 serum levels, atherosclerosis, and cardiovascular diseases. However, a clear link between circulating omentin-1 and PAD in diabetic patients has yet to be established. The aim of this study was to investigate the potential role of omentin-1 in PAD in type-2 diabetic patients., Methods: In this cross-sectional study, we analyzed omentin-1 serum levels by ELISA in 600 type-2 diabetic patients with (n = 300) and without (n = 300) PAD at Fontaine's stage II, III, or IV., Results: We found that omentin-1 serum levels were significantly lower in diabetic patients with PAD than in diabetic controls (29.46 vs 49.24 ng/mL, P < 0.001) and that the levels gradually decreased in proportion to disease severity (P < 0.05). The association between omentin-1 levels and PAD remained significant after adjusting for major risk factors in a multivariate analysis., Conclusions: Our results suggest that omentin-1 is reduced in type 2 diabetic patients with PAD and that omentin-1 levels are related to disease severity.

Aims: To investigate cardiovascular disease and mortality trends in control arm participants of diabetes cardiovascular outcome trials (CVOTs)., Methods: We electronically searched CVOTs published before October 2017. Data on all-cause mortality, cardiovascular mortality and events, and baseline characteristics were collected, along with study calendar years. Trends were estimated using negative binomial regressions and reported as rate ratio (RR) per 5-year intervals., Results: 26 CVOTs, conducted from 1961 to 2015, included 86788 participants with 6543 all-cause deaths, 3265 cardiovascular deaths, and 7657 3-point major adverse cardiovascular events (3-P MACE; combined endpoint of cardiovascular death, nonfatal myocardial infarction, nonfatal stroke). In unadjusted analysis, there was an increasing trend for 3-P MACE rates over time (5-year RR 1.57; 95% CI 1.34, 1.84); a small increasing trend for cardiovascular disease mortality rates (1.13; 1.01, 1.26); and stable rates for all-cause death. Adjusting for age, sex, previous myocardial infarction, and diabetes duration, there was no evidence of trends for 3-P MACE or cardiovascular disease mortality rates, while reducing rates were observed for nonfatal myocardial infarction (5-year RR: 0.72; 0.54, 0.96), total stroke (0.76; 0.66, 0.88), and nonfatal stroke (0.60; 0.43, 0.82)., Conclusions: In contrast to real-world data, there was no evidence of an improvement in all-cause and cardiovascular mortality in type 2 diabetes participants included in control arms of randomised clinical trials across 5 decades. Further studies should investigate whether and how dissimilarities in populations, procedures, and assessments of exposures and outcomes explain the differences between real-world setting and clinical trials.

Aim: Diabetes is a major driver of cardiovascular disease, but the underlying mechanisms remain elusive. Prolyl-isomerase Pin1 recognizes specific peptide bonds and modulates function of proteins altering cellular homoeostasis. The present study investigates Pin1 role in diabetes-induced vascular disease., Methods and Results: In human aortic endothelial cells (HAECs) exposed to high glucose, up-regulation of Pin1-induced mitochondrial translocation of pro-oxidant adaptor p66(Shc) and subsequent organelle disruption. In this setting, Pin1 recognizes Ser-116 inhibitory phosphorylation of endothelial nitric oxide synthase (eNOS) leading to eNOS-caveolin-1 interaction and reduced NO availability. Pin1 also mediates hyperglycaemia-induced nuclear translocation of NF-κB p65, triggering VCAM-1, ICAM-1, and MCP-1 expression. Indeed, gene silencing of Pin1 in HAECs suppressed p66(Shc)-dependent ROS production, restored NO release and blunted NF-kB p65 nuclear translocation. Consistently, diabetic Pin1(-/-) mice were protected against mitochondrial oxidative stress, endothelial dysfunction, and vascular inflammation. Increased expression and activity of Pin1 were also found in peripheral blood monocytes isolated from diabetic patients when compared with age-matched healthy controls. Interestingly, enough, Pin1 up-regulation was associated with impaired flow-mediated dilation, increased urinary 8-iso-prostaglandin F2α and plasma levels of adhesion molecules., Conclusions: Pin1 drives diabetic vascular disease by causing mitochondrial oxidative stress, eNOS dysregulation as well as NF-kB-induced inflammation. These findings provide molecular insights for novel mechanism-based therapeutic strategies in patients with diabetes., (Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2014. For permissions please email: journals.permissions@oup.com.)

Background: Cellular studies showed that histone methyltransferase Set7 mediates high glucose-induced inflammation via epigenetic regulation of the transcription factor NF-kB. However, the link between Set7 and vascular dysfunction in patients with diabetes mellitus remains unknown. This study was designed to investigate whether Set7 contributes to vascular dysfunction in patients with type 2 diabetes mellitus (T2DM)., Methods and Results: Set7-driven epigenetic changes on NF-kB p65 promoter and expression of NF-kB-dependent genes, cyclooxygenase 2 and inducible endothelial nitric oxide synthase, were assessed in peripheral blood mononuclear cells isolated from 68 subjects (44 patients with T2DM and 24 age-matched controls). Brachial artery flow-mediated dilation, 24-hour urinary levels of 8-isoprostaglandin F2α, and plasma adhesion molecules, intercellular cell adhesion molecule-1 and monocyte chemoattractant protein-1, were also determined. Experiments in human aortic endothelial cells exposed to high glucose were performed to elucidate the mechanisms of Set7-driven inflammation and oxidative stress. Set7 expression increased in peripheral blood mononuclear cells from patients with T2DM when compared with controls. Patients with T2DM showed Set7-dependent monomethylation of lysine 4 of histone 3 on NF-kB p65 promoter. This epigenetic signature was associated with upregulation of NF-kB, subsequent transcription of oxidant/inflammatory genes, and increased plasma levels of intercellular cell adhesion molecule-1 and monocyte chemoattractant protein-1. Interestingly, we found that Set7 expression significantly correlated with oxidative marker 8-isoprostaglandin F2α (r=0.38; P=0.01) and flow-mediated dilation (r=-0.34; P=0.04). In human aortic endothelial cells, silencing of Set7 prevented monomethylation of lysine 4 of histone 3 and abolished NF-kB-dependent oxidant and inflammatory signaling., Conclusions: Set7-induced epigenetic changes contribute to vascular dysfunction in patients with T2DM. Targeting this chromatin-modifying enzyme may represent a novel therapeutic approach to prevent atherosclerotic vascular disease in this setting., (© 2014 American Heart Association, Inc.)

The thrombogenic activity of Von Willebrand factor (VWF) is proportional to its molecular size and inversely related to its proteolysis by ADAMTS-13. Oxidation of VWF severely impairs its proteolysis by the metalloprotease. This study was aimed at assessing in patients with type 1 and type 2 diabetes whether protein carbonyls, marker of oxidative stress, are associated with both the level and oxidation status of VWF as well as with micro- and macroangiopathic complications. Eighty-three diabetic patients (41 type 1 and 42 type 2 diabetic subjects) and their respective eighty-three healthy controls were studied after verifying the availability, through institutional databases, of clinical biochemistry records spanning at least 3 years. VWF and protein carbonyls were measured by immunoassays, whereas VWF multimers were studied by SDS-agarose gel electrophoresis. Type 2 diabetic subjects had higher levels of VWF antigen (VWF:ag), VWF activity (VWF:act) and plasma proteins' carbonyls compared to both their controls and type 1 diabetic subjects. Moreover, high molecular weight VWF multimers and specific VWF-bound carbonyls were significantly increased in subjects with micro- and macro-angiopathic complications. In both type 1 and type 2 diabetic subjects, ADAMTS-13 activity was in the normal range. In a multivariable analysis, only VWF-bound carbonyls were significantly associated with any form of thrombotic angiopathy in the entire group of T1- and T2 diabetic patients. These data provide first evidence that not only high VWF levels but also its oxidation status and the presence of high molecular weight VWF multimers that are not observed in SDS-agarose gel electrophoresis of normal subjects are associated with thrombotic angiopathies in diabetes mellitus. These findings may help identify diabetic patients particularly at risk for these complications and elucidate a new pathophysiological mechanism of thrombotic angiopathies in this clinical setting.

The aim of the present study was to investigate the role of GV (glycaemic variability) in diabetic vascular complications and to explore the molecular pathways modulated by glycaemic 'swings'. We developed a murine model. A total of 30 diabetic mice received once daily basal insulin administration plus two oral boluses of glucose solution (GV group, named 'V') and 30 diabetic mice received once daily basal insulin plus two oral boluses of saline solution (stable hyperglycaemia group, named 'S') for a period of 30 days. Glycaemia was measured eight times daily to detect GV. Finally, postischaemic vascularization, induced by hindlimb ischaemia 30 days after diabetes onset, was evaluated. We found that GV was significantly different between S and V groups, whereas no significant difference in the mean glycaemic values was detected. Laser Doppler perfusion imaging and histological analyses revealed that the ischaemia-induced angiogenesis was significantly impaired in V mice compared with S group, after ischaemic injury. In addition, immunostaining and Western blot analyses revealed that impaired angiogenic response in V mice occurred in association with reduced VEGF (vascular endothelial growth factor) production and decreased eNOS (endothelial nitric oxide synthase) and Akt (also called protein kinase B) phosphorylation. In conclusion, we describe a murine model of GV. GV causes an impairment of ischaemia-induced angiogenesis in diabetes, likely to be independent of changes in average blood glucose levels, and this impaired collateral vessel formation is associated with an alteration of the VEGF pathway.

Aims: Diabetes mellitus (DM) is associated with high incidence of first and recurrent cardiovascular events, especially acute coronary syndromes (ACSs); however, the mechanisms involved are still unknown. We sought to investigate the role of CD4(+)CD28(null)T-lymphocytes, a rare long-lived subset of T-lymphocytes with proatherogenic and plaque-destabilizing properties, in the increased cardiovascular risk associated with DM., Methods and Results: CD4(+)CD28(null)T-cell frequency was analysed by flow-cytometry in 60 DM patients without overt cardiovascular disease (cDM), in 166 ACS patients with or without DM (ACS/DM+, n= 51 and ACS/DM-, n= 115), and in 60 healthy individuals. The incidence of cardiovascular events (death, myocardial infarction, unstable angina) was assessed at 36 months follow-up. CD4+CD28(null)T-cell frequency (median, range) was higher in ACS/DM+ (12.7%, 0.1-48) vs. ACS/DM- (3.9%, 0.2-35), cDM (3.1%, 0.3-22.4), and controls (1.5%, 0.1-9.1) (P< 0.001 for all comparisons). Notably, cDM patients had significantly higher CD4+CD28(null)T-cell frequency than controls (P= 0.001). Glycosylated haemoglobin A(1c) was the only parameter independently associated with CD4+CD28(null)T-cells in cDM. The 36-month event-free survival was significantly lower in cDM patients with CD4+CD28(null)T-cells ≥4% (90th percentile of normal distribution) than in those with CD4+CD28(null)T-cells <4% (P= 0.039). Among ACS patients, the 36-month event-free survival was the lowest in those with DM and CD4+CD28(null)T-cells ≥4% and highest in those without DM and CD4+CD28(null)T-cells <4% (P< 0.001), being intermediate in those with only one of these features., Conclusions: In DM patients, CD4+CD28(null)T-cells are expanded and are associated with poor glycaemic control; they also correlate with the occurrence of a first cardiovascular event and with a worse outcome after an ACS.

Background and Objectives: Glycemic control has been suggested to improve prognosis in diabetic patients, but recent trials failed to show benefits from intensive glycemic control. Hypoglycaemic episodes or large variability in glucose blood levels causing a sympatho-vagal imbalance of cardiac autonomic function (CAF) might play a role in this result. In our study we assessed whether blood glucose fluctuation may be related to variations in CAF during daily life in diabetic patients with coronary artery disease (CAD)., Materials and Methods: Twelve patients with type 2 diabetes mellitus with CAD (65+/-4 years, 2 women) underwent simultaneous 48-hour ECG Holter monitoring and continuous interstitial glucose measurements. The highest and lowest glucose levels for each 3-hour segments of the day were identified and heart rate variability (HRV) parameters were measured on Holter recordings on 5-minute intervals centred on these times., Results: Overall, 294 glucose levels were available for analysis. In the whole population several HRV indices were significantly lower in correspondence of the lowest glucose blood levels and this difference was much more evident in patients who were not taking beta-blockers, than in patients who were taking beta-blockers. A significant, although mild, correlation was found between glucose blood levels and several time-and frequency domain HRV variables in patients not taking beta-blockers, but not in these on beta-blockers therapy., Discussion: Our data suggest that, in type 2 diabetic patients with CAD, hypoglycaemic episodes are associated with depressed HRV and that beta-blocking agents are able to contrast this relation. These interesting results merit to be investigated in a larger population of patients.

The peroxisome proliferator-activated receptors (PPARs) are a group of three nuclear receptor isoforms, PPARalpha, PPARgamma and PPARdelta, encoded by different genes, and they form a subfamily of the nuclear receptor superfamily. The clinical interest in PPARs originates with fibrates and thiazolidinediones, which, respectively, act on PPARalpha and PPARgamma and are used to ameliorate hyperlipidaemia and hyperglycaemia in subjects with type 2 diabetes mellitus (T2DM). PPARs play a central role in these patients due to their ability to regulate the expression of numerous genes involved in glycaemic control, lipid metabolism, vascular tone and inflammation. Abnormal angiogenesis is implicated in several of the long-term complications of diabetes mellitus, characterized by vasculopathy associated with aberrant growth of new blood vessels. This pathological process plays a crucial role in diabetic retinopathy, nephropathy and neuropathy, impaired wound healing and impaired coronary collateral vessel development. In recent years, there has been increasing appreciation of the fact that PPARs might be involved in the molecular mechanisms that regulate angiogenesis through the action of growth factors and cytokines that stimulate migration, proliferation and survival of endothelial cells. During the last few years direct comparative analyses have been performed, using selective PPARs agonists, to clarify the angiogenic properties of the different members of the PPAR family. Lately, the findings provide new information to order to understand the biological, clinical and therapeutic effects of PPARs, and the role of these nuclear receptors in angiogenesis, with potentially important implications for the management of subjects affected by T2DM.

Aims: Although aspirin treatment is useful in reducing ischaemic events in diabetic patients, recent studies suggest that it is less effective when compared with non-diabetics (ND). We sought to evaluate COX-1 sensitivity and thromboxane A(2) (TxA(2)) production in type 1 (T1DM) and type 2 diabetic (T2DM) patients under chronic aspirin treatment, and also evaluate the association between thromboxane A(2) (TxA(2)) production and markers of inflammation and metabolic control, such as high-sensitivity C-reactive protein, fasting blood glucose, and haemoglobin A1c (HbA1c)., Methods and Results: Agonist-induced platelet aggregation (PA) and TxB(2), a stable metabolite of TxA(2), production, serum TxB(2), and platelet COX-1 and COX-2 expression were studied in T2DM patients, T1DM patients, and high-risk ND subjects, all receiving a low dose of aspirin. TxB(2) formation was studied in platelets treated in vitro with aspirin alone or with a COX-2 inhibitor (NS-398). PA, collagen-induced TxB(2) production, and serum TxB(2) were higher in T1DM and T2DM patients than in ND subjects. TxB(2) production was reduced in diabetic patients by in vitro treatment with aspirin. COX-2 was expressed in all diabetic patients but only in 46% of ND patients. In diabetic patients significant correlations were observed between TxB(2) production and both fasting plasma glucose and HbA1c., Conclusion: COX-1 sensitivity and TxB(2) production is similarly reduced in both T1DM and T2DM patients under chronic aspirin treatment. The association between TxB(2) production and either fasting plasma glucose and HbA1c levels suggests that in diabetic patients hyperglycaemia is a determinant of the reduced platelet sensitivity to aspirin.

Achieving adequate targets relatively to all risk factors is considered a standard of care for patients with diabetes mellitus. To date, current guidelines underline the importance of the 'glucose triad' (post-prandial glucose, fasting plasma glucose and glycated haemoglobin) as the three glycemic factors that should be controlled in diabetes care; however, several literature data show that optimizing glycemic control needs achieving a control of glycemic variations. The objective of the present work is reviewing biological and clinical data supporting the role of glycemic variability, its measurement and relationship with the three other well-known glycemic risk factors and evidencing the areas that need further investigation. At last, we propose a simple model that summarizes the 'glucose triad' plus the 'new' risk factor glycemic variability (the 'Pyramid of the Risk').

Background: In Type 1 diabetes mellitus (DM), it has been suggested that autonomic nervous system dysfunction (NAD) impairs lung diffusion capacity. Heart rate variability (HRV), a measure of cardiac autonomic function, is a sensitive method of detecting NAD. To our knowledge, no previous study has assessed whether cardiac sympatho-vagal balance is associated with lung diffusion capacity in diabetes., Methods: Twenty Type 1 DM patients without pulmonary abnormalities and systemic NAD underwent measurement of lung diffusion capacity for carbon monoxide (DLCO) by single-breath method and assessment of cardiac autonomic function by HRV analysis on 24-h electrocardiographic Holter recordings., Results: Standard respiratory function tests and peripheral autonomic tests were normal in all patients. DLCO was lower than normal reference values in six patients (30%). DLCO correlated significantly with most HRV variables, independent of the clinical and laboratory variables. The strongest correlation was found with standard deviation of all RR intervals (SDNN; r = 0.62, P = 0.003) in the time domain and low frequency (LF) power (r = 0.73, P < 0.001) in the frequency domain., Conclusions: In Type 1 diabetes, a significant association exists between cardiac NAD and reduced DLCO in the absence of clinical respiratory and autonomic abnormalities. Thus, NAD may be involved in the early reduction of DLCO in these patients, possibly through abnormalities in the regulation of pulmonary blood flow at the microvascular level.