Circulating adhesion molecules in humans: role of hyperglycemia and hyperinsulinemia

Association of stress hyperglycemia ratio with left ventricular function and microvascular obstruction in patients with ST-segment elevation myocardial infarction: a 3.0 T cardiac magnetic resonance study

BACKGROUND

Stress hyperglycemia, which is associated with poor prognosis in patients with acute myocardial infarction (AMI), can be determined using the stress hyperglycemia ratio (SHR). Impaired left ventricular function and microvascular obstruction (MVO) diagnosed using cardiac magnetic resonance (CMR) have also been proven to be linked to poor prognosis in patients with AMI and aid in risk stratification. However, there have been no studies on the correlation between fasting SHR and left ventricular function and MVO in patients with acute ST-segment elevation myocardial infarction (ASTEMI). Therefore, this study aimed to investigate the additive effect of fasting SHR on left ventricular function and global deformation in patients with ASTEMI and to explore the association between fasting SHR and MVO.

METHODS

Consecutive patients who underwent CMR at index admission (3-7 days) after primary percutaneous coronary intervention (PPCI) were enrolled in this study. Basic clinical, biochemical, and CMR data were obtained and compared among all patients grouped by fasting SHR tertiles: SHR1: SHR < 0.85; SHR2: 0.85 ≤ SHR < 1.01; and SHR3: SHR ≥ 1.01. Spearman's rho (r) was used to assess the relationship between fasting SHR and left ventricular function, myocardial strain, and the extent of MVO. Multivariable linear regression analysis was performed to evaluate the determinants of left ventricular function and myocardial strain impairment in all patients with AMI. Univariable and multivariable regression analyses were performed to investigate the correlation between fasting SHR and the presence and extent of MVO in patients with AMI and those with AMI and diabetes mellitus (DM).

RESULTS

A total of 357 patients with ASTEMI were enrolled in this study. Left ventricular ejection fraction (LVEF) and left ventricular global function index (LVGFI) were significantly lower in SHR2 and SHR3 than in SHR1. Compared with SHR1 and SHR2 groups, left ventricular strain was lower in SHR3, as evidenced by global radial (GRS), global circumferential (GCS), and global longitudinal (GLS) strains. Fasting SHR were negatively correlated with LVEF, LVGFI, and GRS (r = - 0.252; r = - 0.261; and r = - 0.245; all P<0.001) and positively correlated with GCS (r = 0.221) and GLS (r = 0.249; all P <0.001). Multivariable linear regression analysis showed that fasting SHR was an independent determinant of impaired LVEF, LVGFI, GRS, and GLS. Furthermore, multivariable regression analysis after adjusting for covariates signified that fasting SHR was associated with the presence and extent of MVO in patients with AMI and those with AMI and DM.

CONCLUSION

Fasting SHR in patients with ASTEMI successfully treated using PPCI is independently associated with impaired cardiac function and MVO. In patients with AMI and DM, fasting SHR is an independent determinant of the presence and extent of MVO.

Common mechanisms underlying diabetic vascular complications: focus on the interaction of metabolic disorders, immuno-inflammation, and endothelial dysfunction

Diabetic vascular complications (DVCs), including macro- and micro- angiopathy, account for a high percentage of mortality in patients with diabetes mellitus (DM). Endothelial dysfunction is the initial and role step for the pathogenesis of DVCs. Hyperglycemia and lipid metabolism disorders contribute to endothelial dysfunction via direct injury of metabolism products, crosstalk between immunity and inflammation, as well as related interaction network. Although physiological and phenotypic differences support their specified changes in different targeted organs, there are still several common mechanisms underlying DVCs. Also, inhibitors of these common mechanisms may decrease the incidence of DVCs effectively. Thus, this review may provide new insights into the possible measures for the secondary prevention of DM. And we discussed the current limitations of those present preventive measures in DVCs research. Video Abstract.

Effects of dietary-based weight loss interventions on biomarkers of endothelial function: a systematic review and meta-analysis

Endothelial dysfunction is closely linked to the development of atherosclerosis. This systematic review and meta-analysis reviewed the evidence on the effect of weight loss, achieved by dietary-based interventions, on biomarkers of endothelial function (EF). Two databases (Medline, Embase) were searched from inception until November 2022 for studies that met the following criteria: 1) adult subjects (≥ 18 years) without exclusion for health status, 2) dietary interventions for weight loss, and 3) measurements of changes in EF biomarkers. Random-effect meta-analysis and meta-regression were performed. Thirty-seven articles including 1449 participants were included in the systematic review. Study duration ranged from 3-52 weeks. Overall, weight loss significantly improved biomarkers of EF [standardised mean difference (SMD):0.65; 95%CI:0.49,0.81; P < 0.001;I2 = 91.9%]. Subgroup analyses showed weight loss significantly improved levels of E-selectin (P < 0.001), intercellular adhesion molecule-1 (ICAM-1) (P < 0.001), vascular cell adhesion molecule-1 (VCAM-1) (P < 0.001), nitrite/nitrate (NOx) (P < 0.001) and vascular endothelial growth factor (VEGF) (P < 0.001). Conversely, there was no significant improvement for von Willebrand Factor (vWF). Meta-regression analysis revealed that changes in EF biomarkers were not affected by age, BMI, quality of the studies or the amount of weight lost. A significant heterogeneity was observed for the effects of weight loss on changes in EF biomarkers. Dietary-induced weight loss may be associated with biomarkers changes indicating an improvement of EF, and it may represent a potential strategy to reduce atherosclerotic risk.

Long-Term Effects of Suramin on Renal Function in Streptozotocin-Induced Diabetes in Rats

In short-term diabetes (3 weeks), suramin, a drug used clinically, affects renal function and the expression of vascular endothelial growth factor A (VEGF-A), which may be involved in the pathogenesis of diabetic nephropathy, the main cause of end-stage renal disease. In the present study, we evaluated the long-term (11 weeks) effects of suramin (10 mg/kg, i.p., once-weekly) in diabetic rats. Concentrations of VEGF-A, albumin, soluble adhesive molecules (sICAM-1, sVCAM-1), nucleosomes, and thrombin-antithrombin complex (TAT) were measured by ELISA, total protein was measured using a biuret reagent. Glomerular expression of VEGF-A was evaluated by Western blot, mRNA for VEGF-A receptors in the renal cortex by RT-PCR. The vasoreactivity of the interlobar arteries to acetylcholine was assessed by wire myography. Long-term diabetes led to an increased concentration of VEGF-A, TAT, and urinary excretion of total protein and albumin, and a decrease in the concentration of sVCAM-1. We have shown that suramin in diabetes reduces total urinary protein excretion and restores the relaxing properties of acetylcholine relaxation properties to non-diabetic levels. Suramin had no effect on glomerular expression VEGF-A expression and specific receptors, and on sICAM-1 and nucleosomes concentrations in diabetic rats. In conclusion, the long-term effect of suramin on the kidneys in diabetes, expressed in the reduction of proteinuria and the restoration of endothelium-dependent relaxation of the renal arteries, can be considered as potentially contributing to the reduction/slowing down of the development of diabetic nephropathy.

Suramin Affects the Renal VEGF-A/VEGFR Axis in Short-Term Streptozotocin-Induced Diabetes

Diabetic nephropathy (DN) accounts for approximately 50% of end-stage renal diseases. Vascular endothelial growth factor A (VEGF-A) is thought to be a critical mediator of vascular dysfunction in DN, but its role is unclear. The lack of pharmacological tools to modify renal concentrations further hinders the understanding of its role in DN. In this study, rats were evaluated after 3 weeks of streptozotocin-induced diabetes and two suramin treatments (10 mg/kg, ip). Vascular endothelial growth factor A expression was evaluated by western blot of glomeruli and immunofluorescence of the renal cortex. RT-PCR for receptors Vegfr1 mRNA and Vegfr2 mRNA quantitation was performed. The soluble adhesive molecules (sICAM-1, sVCAM-1) in blood were measured by ELISA and the vasoreactivity of interlobar arteries to acetylcholine was evaluated using wire myography. Suramin administration reduced the expression and intraglomerular localisation of VEGF-A. Increased VEGFR-2 expression in diabetes was reduced by suramin to non-diabetic levels. Diabetes reduced the sVCAM-1 concentrations. Suramin in diabetes restored acetylcholine relaxation properties to non-diabetic levels. In conclusion, suramin affects the renal VEGF-A/VEGF receptors axis and has a beneficial impact on endothelium-dependent relaxation of renal arteries. Thus, suramin may be used as a pharmacological agent to investigate the potential role of VEGF-A in the pathogenesis of renal vascular complications in short-term diabetes.

ETS proto-oncogene 1 modulates PTP1B expression to participate in high glucose-mediated endothelial inflammation

Hyperglycemia-induced endothelial inflammation participates in the pathogenesis of cardiovascular complications in diabetics. Previous studies showed that protein tyrosine phosphatase 1B (PTP1B) and ETS proto-oncogene 1 (ets1) are involved in hyperglycemia-induced endothelial inflammation. In this study, we hypothesized that ets1 modulates PTP1B expression, thus playing a crucial role in hyperglycemia-induced vascular endothelial inflammation. Our results indicated that high glucose increases monocyte/endothelial adhesion, vascular cell adhesion molecule-1 (VCAM-1) expression and p65 phosphorylation in human umbilical vein endothelial cells (HUVECs). Moreover, high glucose-mediated endothelial inflammation is reversed by PTP1B silencing. In addition, high glucose increases ets1 expression in HUVECs. silencing reverses high glucose-mediated endothelial inflammation. Furthermore, the effect of ets1 overexpression is similar to that of high glucose treatment, which is counteracted by si-PTP1B. The results from ChIP assays indicated that ets1 occupies the PTP1B promoter region. Ets1 overexpression enhances PTP1B promoter activity, which is disappeared after specific binding site mutation. experiments demonstrated that the expressions of VCAM-1, PTP1B, and ets1, as well as the phosphorylation of p65 are augmented in the aorta of diabetic rats. In conclusion, ets1 contributes to hyperglycemia-mediated endothelial inflammation via upregulation of PTP1B expression.

Evaluation of Vascular Endothelial Function in Children with Type 1 Diabetes Mellitus

Diabetic kidney disease belongs to the major complications of diabetes mellitus. Here, hyperglycaemia is a key metabolic factor that causes endothelial dysfunction and vascular changes within the renal glomerulus. The aim of the present study was to assess the function of the vascular endothelium in children with type 1 diabetes mellitus (type 1 diabetes) by measuring selected endothelial lesion markers in blood serum. The selected markers of endothelial lesions (sVCAM-1, sICAM-1, sE-SELECTIN, PAI-1, ADMA and RAGE) were assayed by the immunoenzymatic ELISA method. The study involved 66 patients (age: 5–18 years) with type 1 diabetes and 21 healthy controls (age: 5–16 years). In the type 1 diabetes patients, significantly higher concentrations of all of the assayed markers were observed compared to the healthy controls (p < 0.001). All of the evaluated markers positively correlated with the disease duration, the age, and BMI of the patients, while only PAI-1 and sE-SELECTIN were characteristic of linear correlations with the estimated glomerular filtration rate (eGFR). It can be concluded that endothelial inflammatory disease occurs in the early stages of type 1 diabetes mellitus in children. The correlations between PAI-1, sE-SELECTIN, and eGFR suggest an advantage of these markers over other markers of endothelial dysfunction as prognostic factors for kidney dysfunction in children with type 1 diabetes.

Propofol But Not Desflurane Maintains Rat Cerebral Arteriolar Responses to Acetylcholine During Acute Hyperglycemia

BACKGROUND

Acute hyperglycemia causes vascular endothelial dysfunction in various organs including the cerebral vessels. It is associated with increased mortality and morbidity in the perioperative period. The impact of anesthetic agents on cerebral vasodilatory responses during hyperglycemia remains unclear. We investigated endothelial function in rat cerebral arterioles during acute hyperglycemia, under propofol or desflurane anesthesia.

MATERIALS AND METHODS

A closed cranial window preparation was used to measure changes in pial arteriole diameter induced by topical application of acetylcholine (ACh), an endothelium-dependent vasodilator, in rats anesthetized with propofol or desflurane. Pial arteriole responses to ACh were measured during normoglycemia and hyperglycemia. We then investigated whether the response of cerebral arterioles to acute hyperglycemia under propofol anesthesia were related to propofol or its vehicle, intralipid.

RESULTS

ACh resulted in a dose-dependent dilation of cerebral arterioles during propofol and desflurane anesthesia under normoglycemic conditions. The vasodilatory effects of ACh were also maintained under hyperglycemic conditions during propofol anesthesia, but the vasodilator response to ACh was significantly impaired during hyperglycemia compared with normoglycemia with desflurane anesthesia. The vasodilatory effects of ACh were maintained during normoglycemia and hyperglycemia in rats receiving propofol or intralipid.

CONCLUSIONS

Rat pial arteriole responses to ACh are maintained during conditions of acute hyperglycemia with propofol anesthesia but suppressed compared with normoglycemia with desflurane anesthesia.

Effect of Diabetes Mellitus and Left Ventricular Perfusion on Frequency of Development of Heart Failure and/or All-cause Mortality Late After Acute Myocardial Infarction

Type 2 diabetes mellitus (DM) has a detrimental impact on cardiovascular outcomes, with implications for prognosis following ST elevation myocardial infarction (STEMI).The aim was to evaluate the impact of DM and myocardial perfusion on the long-term risk of heart failure (HF) and/or all-cause mortality following primary percutaneous coronary intervention (pPCI) for STEMI. A total of 406 STEMI patients (104 with DM) treated with pPCI were enrolled in this observational study. Myocardial perfusion was reassessed with the Quantitative Myocardial Blush Evaluator. Follow-up data on HF (ICD10 [International Statistical Classification of Diseases] codes I50.0 - I50.9) and all-cause mortality were obtained from the National Health Fund. During a 6-year follow-up, 36 (35%) patients with DM died compared with 45 (15%) patients without DM (p <0.001). Also, 24 (23%) patients with DM developed HF compared with 51 (17%) patients without DM (p = 0.20). Patients with DM and HF had the highest mortality rate (75%), and those with DM and a QuBE score below the median value (9.0 arb. units) had significantly higher risk of HF (hazard ratio [HR] =1.96, 95% CI 1.18 to 3.27, p = 0.0099) and the composite of HF and/or all-cause mortality (HR = 1.89, 95% CI 1.33 to 2.69, p = 0.0004). In conclusion DM (type 2) and diminished myocardial perfusion increase the risk of HF and/or all-cause mortality during a 6-year follow-up after pPCI for STEMI.

In-Hospital Peak Glycemia in Predicting No-Reflow Phenomenon in Diabetic Patients with STEMI Treated with Primary Percutaneous Coronary Intervention

Although percutaneous coronary intervention (PCI) significantly improves the prognosis for myocardial infarction, the no-reflow phenomenon is still the major adverse complication of PCI leading to increased mortality, especially for the patients with ST-segment elevation myocardial infarction (STEMI) combined with diabetes. To reduce the occurrence of no-reflow, prognostic factors must be identified for no-reflow phenomenon before PCI. A total of 262 participants with acute STEMI and diabetes were recruited into our cardiovascular center and underwent primary PCI for the analyses of prognostic factors of no-reflow. The patients were divided into two groups according to thrombolysis in myocardial infarction (TIMI): the normal flow and no-reflow groups, and related factors were analyzed with different statistical methods. In the present investigation, the in-hospital peak glycemia was significantly higher in the no-reflow group than the normal flow group, while more narrowed vessels, higher level of initial TIMI flow, were observed in the patients of the no-reflow group. A multivariate logistic regression analysis further demonstrated that peak glycemia was an independent predictor for no-reflow in the diabetic patients with STEMI. Our data indicated the importance of the proper control of glucose before PCI for the diabetic patients with STEMI before PCI to reduce the occurrence of the no-reflow after operation.

Role of Fluid Milk in Attenuating Postprandial Hyperglycemia and Hypertriglyceridemia

Postprandial plasma glucose and triglyceride concentrations are predictive of relative cardiovascular disease (CVD) risk, and the pathogenesis of both insulin resistance and atherosclerosis has been attributed to acute states of hyperglycemia and hypertriglyceridemia. Postprandial lipemia and hyperglycemia suppress vascular reactivity and induce endothelial dysfunction. Epidemiological studies suggest that chronically-high consumption of milk and milk products is associated with a reduced risk of type 2 diabetes, metabolic syndrome, and CVD. The addition of dairy products to meals high in carbohydrates and fat may lessen these risks through reductions in postprandial glucose and triglyceride responses. Purported mechanisms include dairy proteins and bioactive compounds, which may explain the inverse relationship between dairy consumption and cardiometabolic diseases. The current review evaluates the available literature describing the relationships between metabolic dysfunction, postprandial metabolism, and vascular dysfunction and discusses the potential role of milk and dairy products in attenuating these impairments.

Carotid imaging changes and serum IL-1β, sICAM-1, and sVAP-1 levels in benign paroxysmal positional vertigo

Benign paroxysmal positional vertigo (BPPV) is the most common cause of vertigo. This study was performed to evaluate serum levels of inflammatory factors and changes in B-mode carotid ultrasound findings in patients with BPPV. The study population consisted of 90 BPPV patients and 90 age- and sex-matched controls. ELISA was used to compare the levels of inflammatory factors, such as interleukin-1β (IL-1β), tumor necrosis factor-alpha (TNF-α), soluble intercellular adhesion molecule-1 (sICAM-1), prostaglandin-E2 (PG-E2), and soluble vascular adhesion protein-1 (sVAP-1), between BPPV patients and controls. In addition, the results of ultrasonographic imaging to determine carotid intima-media thickness (C-IMT), carotid atheromatous plaque, and vertebral artery stenosis were also compared between the BPPV and control groups. Serum levels of IL-1β, sICAM-1, and sVAP-1 were significantly higher in BPPV patients than controls (P < 0.001, P < 0.05, and P < 0.001, respectively). C-IMT and vertebral artery stenosis were significantly different in BPPV patients compared to controls (both P < 0.05). There were no significant relations between other parameters and BPPV. IL-1β, sICAM-1, and sVAP-1 are potentially associated with the pathogenesis of BPPV, and C-ITM and carotid vertebral stenosis may be useful reference imaging findings for the diagnosis of BPPV.

SET8 suppression mediates high glucose-induced vascular endothelial inflammation via the upregulation of PTEN

Hyperglycemia-mediated endothelial inflammation participates in the pathogenesis of cardiovascular complications in subjects with diabetes. Previous studies reported that phosphatase and tensin homolog deleted on chromosome ten (PTEN) and SET8 participate in high glucose-mediated endothelial inflammation. In this study, we hypothesize that SET8 regulates PTEN expression, thus contributing to high glucose-mediated vascular endothelial inflammation. Our data indicated that plasma soluble intercellular adhesion molecule-1 (sICAM-1) and endothelial selectin (e-selectin) were increased in patients with diabetes and diabetic rats. PTEN expression was augmented in the peripheral blood mononuclear cells of patients with diabetes and in the aortic tissues of diabetic rats. Our in vitro study indicated that high glucose increased monocyte/endothelial adhesion, endothelial adhesion molecule expression and p65 phosphorylation in human umbilical vein endothelial cells (HUVECs). Moreover, high glucose led to endothelial inflammation via upregulation of PTEN. Furthermore, high glucose inhibited SET8 expression and histone H4 lysine 20 methylation (H4K20me1), a downstream target of SET8. SET8 overexpression reversed the effects of high-glucose treatment. shSET8-mediated endothelial inflammation was counteracted by siPTEN. Furthermore, SET8 was found to interact with FOXO1. siFOXO1 attenuated high glucose-mediated endothelial inflammation. FOXO1 overexpression-mediated endothelial inflammation was counteracted by siPTEN. H4K20me1 and FOXO1 were enriched in the PTEN promoter region. shSET8 increased PTEN promoter activity and augmented the positive effect of FOXO1 overexpression on PTEN promoter activity. Our in vivo study indicated that SET8 was downregulated and FOXO1 was upregulated in the peripheral blood mononuclear cells of patients with diabetes and the aortic tissues of diabetic rats. In conclusion, SET8 interacted with FOXO1 to modulate PTEN expression in vascular endothelial cells, thus contributing to hyperglycemia-mediated endothelial inflammation.

High glucose levels in patients with diabetes trigger vascular inflammation by affecting the expression of key proteins in blood vessel linings. Elevated glucose causes inflammation of the endothelium, a thin layer of cells that lines blood and lymph vessels, leading to cardiovascular complications. The phosphatase and tensin homolog protein (PTEN) contributes to endothelial inflammation, but the precise mechanisms are unclear. Xuefang Shen at Fudan University in Shanghai, China, and co-workers demonstrated that elevated glucose increases PTEN expression, with increased levels of the protein found in peripheral blood cells of diabetic patients and aortic tissues of diabetic rats. In further experiments on rats, the researchers found that glucose also suppressed another protein called SET8, which contributed to increased PTEN levels. This suggests that SET8 is involved in PTEN modulation, and that both proteins influence vascular inflammation.

Circulating adhesion molecules and associations with HbA1c, hypertension, nephropathy, and retinopathy in the Treatment Options for type 2 Diabetes in Adolescent and Youth study

BACKGROUND

The Treatment Options for type 2 Diabetes in Adolescent and Youth study, a randomized clinical trial of three treatments for type 2 diabetes (T2DM) in youth, demonstrated treatment failure (defined as sustained HbA1c ≥8%, or inability to wean insulin after 3 months after acute metabolic decomposition) in over half of the participants. Given that binding of mononuclear cells to vascular endothelium, initiated by cellular adhesion molecules and chemokines, is an early step in vascular injury, we sought to evaluate (a) changes in cellular adhesion molecule levels during the trial; (b) effect of diabetes treatment; and (c) association of markers with HbA1c, hypertension, hypercholesterolemia, nephropathy, and retinopathy.

METHODS

Participants (n = 515 of 699) that had baseline assessment of adhesion molecules (monocyte chemoattractant protein-1 [MCP-1], vascular cell adhesion marker [VCAM], intercellular adhesion marker [ICAM], and E-Selectin) and at least one other assessment, measured at month 12, 24, or 36, were included.

RESULTS

Over 1 to 3 years, significant increases in MCP-1 and decreases in VCAM (both P < .0001) concentrations were found; however, no significant interactions were identified with treatment group for any molecule. For every 1% increase in HbA1c, ICAM increased by 1.8%, VCAM by 1.5%, and E-selectin by 6.8% (all P < .0001). E-selectin increased by 3.7% and 4.2% for every 10 mm Hg increase in systolic and diastolic blood pressure, respectively (both P < .0001). ICAM was 10.2% higher and E-selectin was 15.5% higher in participants with microalbuminuria (both P < .01). There was no significant association of adhesion molecule levels with retinopathy.

CONCLUSION

Concentrations of cellular adhesion molecules rise with increasing HbA1c in youth with T2DM, and are associated with blood pressure and microalbuminuria, markers of vascular injury.

Exercise improves metformin 72-h glucose control by reducing the frequency of hyperglycemic peaks

PURPOSE

To determine the separated and combined effects of metformin and exercise on insulin sensitivity and free-living glycemic control in overweight individuals with prediabetes/type 2 diabetes (T2DM).

METHODS

We recruited 16 adults with BMI of 32.7 ± 4.3 kg m^-2 and insulin resistance (HOMA-IR 3.2 ± 0.4) under chronic metformin treatment (1234 ± 465 g day^-1) enrolled in a high-intensity interval training (HIIT) program. Participants underwent four 72-h experimental trials in a random-counterbalanced order: (1) maintaining their habitual metformin treatment (MET); (2) replacing metformin treatment by placebo (CON); (3) placebo plus two HIIT sessions (EX + CON), and (4) metformin plus two HIIT sessions (MET + EX). We used intermittently scanned continuous glucose monitoring (isCGM) during 72 h in every trial to obtain interstitial fluid glucose area under the curve (IFG_AUC) and the percentage of measurements over 180 mg dL^-1 (% IFG_PEAKS). Insulin sensitivity was assessed on the last day of each trial with HOMA-IR index and calculated insulin sensitivity (C_SI) from intravenous glucose tolerance test.

RESULTS

IFG_AUC was lower in MET + EX and MET than in CON (P = 0.011 and P = 0.025, respectively). In addition, IFG_AUC was lower in MET + EX than in EX + CON (P = 0.044). %IFG_PEAKS were only lower in MET + EX in relation to CON (P = 0.028). HOMA-IR and C_SI were higher in CON in comparison with MET + EX (P = 0.011 and P = 0.022, respectively) and MET (P = 0.006 and P < 0.001, respectively). IFG_AUC showed a significant correlation with HOMA-IR.

CONCLUSION

Intense aerobic exercise in patients with diabetes and prediabetes under metformin treatment reduces free-living 72-h blood hyperglycemic peaks. This may help to prevent the development of cardiovascular complications associated with diabetes.

Ketamine attenuates high-glucose-mediated endothelial inflammation in human umbilical vein endothelial cells

Hyperglycemia mediates oxidative stress, thus inducing transcription factor nuclear factor kappa B (NF-κB) activation, increasing endothelial adhesion molecule expression and monocyte/endothelial interaction, and resulting in endothelial injury. Ketamine was reported to attenuate oxidative stress in many cases. In this research, we determined whether and how ketamine protects against high-glucose-mediated augmentation of monocyte/endothelial interaction and endothelial adhesion molecule expression in human umbilical vein endothelial cells. High glucose augmented monocyte/endothelial adhesion and endothelial adhesion molecule expression. High glucose induced reactive oxygen species (ROS) production and augmented phospho-protein kinase C (p-PKC) βII expression and PKC activity. Moreover, high glucose inhibited the inhibitory subunit of nuclear factor-κBα (IκBα) expression in the cytoplasm and induced NF-κB nuclear translocation. Importantly, the effects induced by high glucose were counteracted by ketamine treatment. Further, CGP53353, a PKC βII inhibitor, inhibited high-glucose-mediated NF-κB nuclear translocation, attenuated adhesion molecule expression, and reduced monocyte/endothelial interaction. Further, these effects of ketamine against high-glucose-induced endothelial injury were inhibited by phorbol 12-myristate 13-acetate, a PKC βII activator. In conclusion, ketamine, via reducing ROS accumulation, inhibited PKC βII Ser660 phosphorylation and PKC and NF-κB activation and reduced high-glucose-induced expression of endothelial adhesion molecules and monocyte/endothelial interaction.

Emergence of AnnexinVpos CD31neg CD42blow/neg extracellular vesicles in plasma of humans at extreme altitude

Background

Hypobaric hypoxia has been reported to cause endothelial cell and platelet dysfunction implicated in the formation of microvascular lesions, and in its extremes may contribute to vascular leakage in high altitude pulmonary edema or blood brain barrier disruption leading to cerebral micro-hemorrhage (MH). Platelet function in the development of microvascular lesions remained ill defined, and is still incompletely understood. In this study platelet- and endothelial cell-derived extracellular vesicles (PEV and EEV, respectively) and cell adhesion molecules were characterized in plasma samples of members of a high altitude expedition to delineate the contribution of platelets and endothelial cells to hypobaric hypoxia-induced vascular dysfunction.

Methods and findings

In this observational study, platelet and endothelial cell-derived extracellular vesicles were analysed by flow-cytometry in plasma samples from 39 mountaineers participating in a medical research climbing expedition to Himlung Himal, Nepal, 7,050m asl. Megakaryocyte/platelet-derived AnnexinV^pos, PECAM-1 (CD31) and glycoprotein-1b (GP1b, CD42b) positive extracellular vesicles (PEV) constituted the predominant fraction of EV in plasma samples up to 6,050m asl. Exposure to an altitude of 7,050m led to a marked decline of CD31^pos CD42^neg EEV as well as of CD31^pos CD42b^pos PEV at the same time giving rise to a quantitatively prevailing CD31^neg CD42b^low/neg subpopulation of AnnexinV^pos EV. An almost hundredfold increase in the numbers of this previously unrecognized population of CD31^neg CD42b^low/neg EV was observed in all participants reaching 7,050m asl.

Conclusions

The emergence of CD31^neg CD42b^low/neg EV was observed in all participants and thus represents an early hypoxic marker at extreme altitude. Since CD31 and CD42b are required for platelet-endothelial cell interactions, these hypobaric hypoxia-dependent quantitative and phenotypic changes of AnnexinV^pos EV subpopulations may serve as early and sensitive indicators of compromised vascular homeostasis.

Association of Hyperglycemia and Final TIMI Flow with One-Year Mortality of Patients with Acute ST-Segment Elevation Myocardial Infarction Undergoing Primary PCI

The association of hyperglycemia at admission and final thrombolysis in myocardial infarction (TIMI) flow with 1-year mortality of patient with acute ST-segment elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PCI) has not much been explored. We evaluated the association of hyperglycemia and final TIMI flow with 1-year mortality in patients with acute STEMI who underwent primary PCI. We retrospectively analyzed 856 patients with STEMI who underwent primary PCI in a tertiary care academic center between January 2014 and July 2016. Based on the receiver operating characteristics curve, the cutoff used for hyperglycemia in this study was greater than or equal to 169 mg/dL. Cox proportional hazard model was used to determine the association of hyperglycemia and TIMI flow with 1-year mortality. Compared with patients with lower blood glucose level (<169 mg/dL; n  = 549), a greater proportion of patients who presented with hyperglycemia (≥169 mg/dL; n  = 307) had final TIMI flow 0 to 1 (3.3 vs. 0.5%; adjusted odds ratio = 5.58, 95% confidence interval [CI] 1.30-23.9, p  = 0.02). Hyperglycemia was associated with an increased risk for 1-year mortality (adjusted hazard ratio [HR]= 2.0, 95% CI: 1.13-3.53, p  = 0.017). Multivariable Cox regression showed that the interaction of hyperglycemia and final TIMI flow 0 to 1 was associated with an elevated risk for 1-year mortality (adjusted HR= 9.4, 95% CI: 2.34-37.81, p  = 0.002). A higher proportion of patients with acute STEMI who presented with hyperglycemia had final TIMI flow 0 to 1 after primary PCI. The interaction of hyperglycemia and final TIMI flow 0 to 1 was associated with an increased risk for 1-year mortality. This study suggests that aggressive control of hyperglycemia prior to primary PCI may facilitate better angiographic and clinical outcomes after primary PCI. Clinical Trial Registration  Clinicaltrials.gov Identifier number: NCT02319473.

Mast cell-deficiency protects mice from streptozotocin-induced diabetic cardiomyopathy

Mast cells (MCs) have been implicated in the pathogenesis of cardiometabolic diseases by releasing pro-inflammatory mediators. Patients and animals with diabetic cardiomyopathy (DCM) also show inflammatory cell accumulation in the heart. Here, we detected MCs in mouse heart after streptozotocin (STZ)-induced DCM. DCM production caused significant systole and diastole interventricular septum and left ventricular (LV) posterior wall thinning, and systolic LV internal dilation in wild-type (WT) mice. DCM production also led to significant reductions of fractional shortening percentage, heart rate, body weight, heart weight, and significant increases of kidney, pancreas, and lung weight to body weight ratios, and blood hemoglobin HbA1c and glucose levels in WT mice. All these changes were improved or disappeared in MC-deficient Kit^W-sh/W-sh mice. In the myocardium from WT DCM mice, we detected significant decrease of cardiac cell proliferation and increases of cardiac cell death, chemokine expression, macrophage infiltration, inflammatory cytokine expression, and collagen deposition. These changes were also improved or disappeared in Kit^W-sh/W-sh DCM mice. Adoptive transfer of bone marrow-derived MCs (BMMCs) from WT mice fully or partially reversed these cardiac functional and morphologic changes in Kit^W-sh/W-sh DCM recipient mice. Yet, adoptive transfer of BMMCs from Il6^-/- and Tnf^-/- mice failed to make these corrections or at much less extent than the WT BMMCs. Mechanistic studies demonstrated a role of MC and MC-derived IL6 and TNF-α in promoting cardiomyocyte death and cardiac fibroblast TGF-β signaling, and collagen synthesis and deposition. Therefore, MC inhibition may have therapeutic potential in attenuating DCM progression.

Impact of Exercise on Inflammatory Mediators of Metabolic and Vascular Insulin Resistance in Type 2 Diabetes

The development of obesity is cornerstone in the etiology of metabolic and vascular insulin resistance and consequently exacerbates glycemic control. Exercise is an efficacious first-line therapy for type 2 diabetes that improves insulin action through, in part, reducing hormone mediated inflammation. Together, improving the coordination of skeletal muscle metabolism with vascular delivery of glucose will be required for optimizing type 2 diabetes and cardiovascular disease treatment.

Low-level laser irradiation modifies the effect of hyperglycemia on adhesion molecule levels

Endothelium plays a key role in maintaining vascular homeostasis by secreting active factors involved in many biological processes such as hemostasis, angiogenesis, and inflammation. Hyperglycemia in diabetic patients causes dysfunction of endothelial cells. Soluble fractions of adhesion molecules like sE-selectin and vascular cell adhesion molecule (sVCAM) are considered as markers of endothelial damage. The low-level laser therapy (LLLT) effectively supports the conventional treatment of vascular complications in diabetes, for example hard-to-heal wounds in patients with diabetic foot syndrome. The aim of our study was to evaluate the effect of low-energy laser at the wavelength of 635 nm (visible light) and 830 nm (infrared) on the concentration of adhesion molecules: sE-selectin and sVCAM in the supernatant of endothelial cell culture of HUVEC line. Cells were cultured under high-glucose conditions of 30 mM/L. We have found an increase in sE-selectin and sVCAM levels in the supernatant of cells cultured under hyperglycemic conditions. This fact confirms detrimental influence of hyperglycemia on vascular endothelial cell cultures. LLLT can modulate the inflammation process. It leads to a decrease in sE-selectin and sVCAM concentration in the supernatant and an increase in the number of endothelial cells cultured under hyperglycemic conditions. The influence of LLLT is greater at the wavelength of 830 nm.

Intercellular adhesion molecule-1 in diabetic patients with and without microalbuminuria

BACKGROUND

Nephropathy is a major complication of type 2 diabetes mellitus (T2DM) and is heralded by the insidious development of microalbuminuria (MA). It is suggested that the serum levels of Intercellular Adhesion Molecule-1 (ICAM-1) is correlated with diabetic nephropathy. In this cross-sectional study, we evaluated serum ICAM-1 level in diabetic patients with and without MA.

METHODS

A total of 187 participants were enrolled and were classified into three groups including 40 healthy controls and 2 diabetic groups with (n = 59) or without MA (n = 88). Serum levels of ICAM-1, fasting plasma glucose (FPG), hemoglobin A1c (HbA1c), total cholesterol, high density lipoprotein cholesterol, low density lipoprotein cholesterol, very low density lipoprotein cholesterol and C-reactive protein (CRP) were measured in all three groups. Statistical analyses were performed using the SPSS software. A P-value less than 0.05 was considered statistically significant.

RESULTS

Serum levels of ICAM-1 were significantly higher in diabetic patients irrespective of MA. Moreover, ICAM-1 levels in patients with MA were significantly higher than patients without MA. Patients with MA had significantly higher age and blood pressure compared to those without MA (P = 0.001). Serum levels of ICAM-1 were significantly correlated with age and HbA1c.

CONCLUSIONS

Overall, serum ICAM-1 levels were significantly higher in T2DM patients with MA and it may be associated with the severity of diabetic kidney disease.

Analysis of Factors Associated with Death in Maintenance Hemodialysis Patients: A Multicenter Study in China

Background:

Patients on hemodialysis have a high-mortality risk. This study analyzed factors associated with death in patients on maintenance hemodialysis (MHD). While some studies used baseline data of MHD patients, this study used the most recent data obtained from patients just prior to either a primary endpoint or the end of the study period to find the characteristics of patients preceding death.

Methods:

Participants were selected from 16 blood purification centers in China from January 2012 to December 2014. Patients’ data were collected retrospectively. Based on survival status, the participants were divided into two groups: survival group and the death group. Logistic regression analysis was performed to determine factors associated with all-cause mortality.

Results:

In total, 4104 patients (57.58% male, median age 59 years) were included. Compared with the survival group, the death group had more men and more patients with diabetic nephropathy (DN) and hypertensive nephropathy. The patients preceding death also had lower levels of diastolic blood pressure, hemoglobin, serum albumin, serum calcium, serum phosphate, Kt/V, and higher age. Multivariate analysis revealed that male sex (odd ratio [OR]: 1.437, 95% confidence interval [CI]: 1.094–1.886), age (OR: 1.046, 95% CI: 1.036–1.057), and presence of DN (OR: 1.837, 95% CI: 1.322–2.552) were the risk factors associated with mortality. High serum calcium (OR: 0.585, 95% CI: 0.346–0.989), hemoglobin (OR: 0.974, 95% CI: 0.967–0.981), albumin (OR: 0.939, 95% CI: 0.915–0.963) levels, and dialysis with noncuffed catheter (OR: 0.165, 95% CI: 0.070–0.386) were protective factors based on a multivariate analysis.

Conclusions:

Hemodialysis patients preceding death had lower hemoglobin, albumin, and serum calcium levels. Multivariate analysis showed that male sex, age, DN, low hemoglobin, low albumin, and low serum calcium were associated with death in hemodialysis patients.

Disease drivers of aging

It has long been known that aging, at both the cellular and organismal levels, contributes to the development and progression of the pathology of many chronic diseases. However, much less research has examined the inverse relationship-the contribution of chronic diseases and their treatments to the progression of aging-related phenotypes. Here, we discuss the impact of three chronic diseases (cancer, HIV/AIDS, and diabetes) and their treatments on aging, putative mechanisms by which these effects are mediated, and the open questions and future research directions required to understand the relationships between these diseases and aging.

Oxidative stress and reactive oxygen species in endothelial dysfunction associated with cardiovascular and metabolic diseases

Reactive oxygen species (ROS) are reactive intermediates of molecular oxygen that act as important second messengers within the cells; however, an imbalance between generation of reactive ROS and antioxidant defense systems represents the primary cause of endothelial dysfunction, leading to vascular damage in both metabolic and atherosclerotic diseases. Endothelial activation is the first alteration observed, and is characterized by an abnormal pro-inflammatory and pro-thrombotic phenotype of the endothelial cells lining the lumen of blood vessels. This ultimately leads to reduced nitric oxide (NO) bioavailability, impairment of the vascular tone and other endothelial phenotypic changes collectively termed endothelial dysfunction(s). This review will focus on the main mechanisms involved in the onset of endothelial dysfunction, with particular focus on inflammation and aberrant ROS production and on their relationship with classical and non-classical cardiovascular risk factors, such as hypertension, metabolic disorders, and aging. Furthermore, new mediators of vascular damage, such as microRNAs, will be discussed. Understanding mechanisms underlying the development of endothelial dysfunction is an important base of knowledge to prevent vascular damage in metabolic and cardiovascular diseases.

Atherosclerosis

In this chapter, we discuss the manner through which the immune system regulates the cardiovascular system in health and disease. We define the cardiovascular system and elements of atherosclerotic disease, the main focus in this chapter. Herein we elaborate on the disease process that can result in myocardial infarction (heart attack), ischaemic stroke and peripheral arterial disease. We have discussed broadly the homeostatic mechanisms in place that help autoregulate the cardiovascular system including the vital role of cholesterol and lipid clearance as well as the role lipid homeostasis plays in cardiovascular disease in the context of atherosclerosis. We then elaborate on the role played by the immune system in this setting, namely, major players from the innate and adaptive immune system, as well as discussing in greater detail specifically the role played by monocytes and macrophages.This chapter should represent an overview of the role played by the immune system in cardiovascular homeostasis; however further reading of the references cited can expand the reader's knowledge of the detail, and we point readers to many excellent reviews which summarise individual immune systems and their role in cardiovascular disease.

Review: Diabetes as a procoagulant condition

Major known effects of the metabolic derangements of diabetes in haemostasis are induction of platelet-vascular activation by hyperglycaemia, the increase in fibrinogen, modification of fibrin substrate by glucose and hypofibrinolysis related to insulin resistance. The platelet effects are specifically expressed during high shear stress and may be relevant in particular for developing of micro-angiopathy. Hypofibrinolysis, increased fibrinogen and modifications of fibrin may aggravate microthrombosis and organ damage and contribute to precipitation of coronary and cerebral infarction. In addition to specific anti-diabetic medication to reduce the haemostatic effects, specific antiplatelet and profibrinolytic treatments may be relevant for reducing further the morbidity and mortality in diabetics for both micro- and macro-angiopathy.

Hyperglycemia and Outcome After Myocardial Infarction and Cardiac Surgery: So What?

Hyperglycemia is a frequent observation during acute illness such as myocardial infarction and after major surgery. The proportion of patients with hyperglycemia may be as high as 95% to 100% after cardiac surgery. This stress-induced hyperglycemia has a detrimental effect on outcome after myocardial infarction and cardiac surgery. Mortality may increase by a factor of 4, especially in non-diabetic patients. Control of hyperglycemia to normalize blood glucose is associated with a clear clinical benefit. This effect is most beneficial in nondiabetic patients with hyperglycemia. The exact target level of glycemia is still a matter of investigation, but normalization to values between 80 and 125 mg/dL is probably optimal.

Short-term high-fat diet alters postprandial glucose metabolism and circulating vascular cell adhesion molecule-1 in healthy males

Short-term intake of a high-fat diet aggravates postprandial glucose metabolism; however, the dose-response relationship has not been investigated. We hypothesized that short-term intake of a eucaloric low-carbohydrate/high-fat diet (LCHF) would aggravate postprandial glucose metabolism and circulating adhesion molecules in healthy males. Seven healthy young males (mean ± SE; age: 26 ± 1 years) consumed either a eucaloric control diet (C, approximately 25% fats), a eucaloric intermediate-carbohydrate/intermediate-fat diet (ICIF, approximately 50% fats), or an LCHF (approximately 70% fats) for 3 days. An oral meal tolerance test (MTT) was performed after the 3-day dietary intervention. The concentrations of plasma glucose, insulin, glucagon-like peptide-1 (GLP-1), intercellular adhesion molecule-1, and vascular cell adhesion molecule-1 (VCAM-1) were determined at rest and during MTT. The incremental area under the curve (iAUC) of plasma glucose concentration during MTT was significantly higher in LCHF than in C (P = 0.009). The first-phase insulin secretion indexes were significantly lower in LCHF than in C (P = 0.04). Moreover, the iAUC of GLP-1 and VCAM-1 concentrations was significantly higher in LCHF than in C (P = 0.014 and P = 0.04, respectively). The metabolites from ICIF and C were not significantly different. In conclusion, short-term intake of eucaloric diet containing a high percentage of fats in healthy males excessively increased postprandial glucose and VCAM-1 concentrations and attenuated first-phase insulin release.

Soluble Forms of Intercellular and Vascular Cell Adhesion Molecules Independently Predict Progression to Type 2 Diabetes in Mexican American Families

Objective

While the role of type 2 diabetes (T2D) in inducing endothelial dysfunction is fairly well-established the etiological role of endothelial dysfunction in the onset of T2D is still a matter of debate. In the light of conflicting evidence in this regard, we conducted a prospective study to determine the association of circulating levels of soluble intercellular adhesion molecule 1 (sICAM-1) and soluble vessel cell adhesion molecule 1 (sVCAM-1) with incident T2D.

Methods

Data from this study came from 1,269 Mexican Americans of whom 821 initially T2D-free individuals were longitudinally followed up in the San Antonio Family Heart Study. These individuals were followed for 9752.95 person-years for development of T2D. Prospective association of sICAM-1 and sVCAM-1 with incident T2D was studied using Kaplan-Meier survival plots and mixed effects Cox proportional hazards modeling to account for relatedness among study participants. Incremental value of adhesion molecule biomarkers was studied using integrated discrimination improvement (IDI) and net reclassification improvement (NRI) indexes.

Results

Decreasing median values for serum concentrations of sICAM-1 and sVCAM-1 were observed in the following groups in this order: individuals with T2D at baseline, individuals who developed T2D during follow-up, individuals with prediabetes at baseline and normal glucose tolerant (NGT) individuals who remained T2D-free during follow-up. Top quartiles for sICAM-1 and sVCAM-1 were strongly and significantly associated with homeostatic model of assessment—insulin resistance (HOMA-IR). Mixed effects Cox proportional hazards modeling revealed that after correcting for important clinical confounders, high sICAM-1 and sVCAM-1 concentrations were associated with 2.52 and 1.99 times faster progression to T2D as compared to low concentrations, respectively. Individuals with high concentrations for both sICAM-1 and sVCAM-1 progressed to T2D 3.42 times faster than those with low values for both sICAM-1 and sVCAM-1. The results were similar in women in reproductive age group and the remainder of the cohort. Inclusion of sICAM-1 and sVCAM-1 in predictive models significantly improved reclassification and discrimination. The majority of these results were seen even when the analyses were restricted to NGT individuals.

Conclusion

Serum concentrations of sICAM-1 and sVCAM-1 independently and additively predict future T2D and represent important candidate biomarkers of T2D.

Insulin Therapy, Glycemic Control, and Cardiovascular Risk Factors in Young Latin Americans with Type 2 Diabetes Mellitus

BACKGROUND

Type 2 diabetes has been linked to an increased risk of cardiovascular (CV) disease, but this risk has not been well documented in young patients, especially of Latin American descent. Also, the potential CV benefits of insulin therapy have not been evaluated in young patients with type 2 diabetes. The objectives of this study were to determine any gender-related difference in the presence of CV risk factors in young Latin Americans with poorly controlled type 2 diabetes and the effect of intensive insulin therapy on these CV risk factors.

METHODS AND RESULTS

Fifty-seven Latin American patients with type 2 diabetes between the ages 18 and 45 years were evaluated at baseline. All women were premenopausal and had regular menstrual periods. The mean body mass index (BMI) was > 30 kg/m2 in both genders. Percent body fat, percent hemoglobin A1c, and lipoprotein profiles were similar between genders. Highly sensitive C-reactive protein (CRP) levels were elevated and similar between genders (p = .4). Leukocyte adhesion molecules (intercellular adhesion molecule 1, vascular adhesion molecule 1, E-selectin) and monocyte chemoattractant protein 1 were elevated, whereas adiponectin levels were below normal in both gender groups. Urinary albumin excretion was similar between genders and did not show any relationship with any of the variables. In women, there was a direct relationship between waist circumference and high-sensitivity CRP levels (rho = .53, p = .01). No other significant relationships were observed. Eighteen Latin American patients with type 2 diabetes completed up to 104 weeks of post-intervention with insulin monotherapy. In these patients, glycemic, lipoprotein, and anthropometric measurements were obtained every 12 weeks. Highly sensitive CRP, leukocyte adhesion molecules, and urinary albumin excretion, among other tests, were obtained every 52 weeks. At 52 and 104 weeks, body weight, BMI, waist circumference, and percent body fat increased in a parallel and significant manner. Despite a significant decrease in percent hemoglobin A1c (22.2%; p = < .0001), lipid and lipoprotein profiles, highly sensitive CRP, leukocyte adhesion molecules, and other nontraditional CV risk factors did not change significantly.

CONCLUSIONS

In young, obese, Latino type 2 diabetic patients, improvement in glycemic control with insulin monotherapy was not associated with a parallel improvement in markers of vascular inflammation. Premenopausal Latino women with uncontrolled type 2 diabetes have CV risks comparable to Latino diabetic men of the same age. Obesity and underlying insulin resistance may counteract the potential CV benefits associated with insulin therapy in lean diabetic patients. Weight loss could be a potential therapeutic modality to improve CV risk in Latino type 2 diabetic patients, especially women.

Vascular endothelial dysfunction and pharmacological treatment

The endothelium exerts multiple actions involving regulation of vascular permeability and tone, coagulation and fibrinolysis, inflammatory and immunological reactions and cell growth. Alterations of one or more such actions may cause vascular endothelial dysfunction. Different risk factors such as hypercholesterolemia, homocystinemia, hyperglycemia, hypertension, smoking, inflammation, and aging contribute to the development of endothelial dysfunction. Mechanisms underlying endothelial dysfunction are multiple, including impaired endothelium-derived vasodilators, enhanced endothelium-derived vasoconstrictors, over production of reactive oxygen species and reactive nitrogen species, activation of inflammatory and immune reactions, and imbalance of coagulation and fibrinolysis. Endothelial dysfunction occurs in many cardiovascular diseases, which involves different mechanisms, depending on specific risk factors affecting the disease. Among these mechanisms, a reduction in nitric oxide (NO) bioavailability plays a central role in the development of endothelial dysfunction because NO exerts diverse physiological actions, including vasodilation, anti-inflammation, antiplatelet, antiproliferation and antimigration. Experimental and clinical studies have demonstrated that a variety of currently used or investigational drugs, such as angiotensin-converting enzyme inhibitors, angiotensin AT1 receptors blockers, angiotensin-(1-7), antioxidants, beta-blockers, calcium channel blockers, endothelial NO synthase enhancers, phosphodiesterase 5 inhibitors, sphingosine-1-phosphate and statins, exert endothelial protective effects. Due to the difference in mechanisms of action, these drugs need to be used according to specific mechanisms underlying endothelial dysfunction of the disease.

Acarbose: safe and effective for lowering postprandial hyperglycaemia and improving cardiovascular outcomes

α-Glucosidase inhibitors (AGIs) are a class of oral glucose-lowering drugs used exclusively for treatment or prevention of type 2 diabetes mellitus. AGIs act by altering the intestinal absorption of carbohydrates through inhibition of their conversion into simple sugars (monosaccharides) and thus decrease the bioavailability of carbohydrates in the body, significantly lowering blood glucose levels. The three AGIs used in clinical practice are acarbose, voglibose and miglitol. This review will focus on the cardiovascular properties of acarbose. The current available data suggest that AGIs (particularly acarbose) may be safe and effective for the treatment of prediabetes and diabetes.

Admission hyperglycemia is associated with poor outcome after emergent coronary bypass grafting surgery

PURPOSE

Hyperglycemia during or after cardiac surgery is a common finding that is associated with poor outcome. Very few data, however, are available regarding a correlation between admission blood glucose and outcomes after coronary artery bypass grafting (CABG). Thus, the goal of the current study was to examine the relationship between admission blood glucose and outcome after emergency CABG surgery.

MATERIALS AND METHODS

A retrospective analysis to evaluate whether admission hyperglycemia associated with increased morbidity or mortality was performed in patients after emergency CABG surgery. The records of all the patients undergoing emergency CABG surgery between January 1999 and December 2010 at the University of Virginia Health System were reviewed. Postoperative in-hospital mortality and complications were considered as study end points.

RESULTS

A total of 240 patients met the final inclusion criteria. Overall mortality was 14.1%. The median admission blood glucose in patients who died 7.4 (interquartile range, 5.9-10.1) mmol/L was significantly higher compared with survivors 6.1 (interquartile range, 5.4-7.2; P<.01). Furthermore, 59% of the patients who died had admission blood glucose levels higher than 6.6 mmol/L, whereas only 35% of the patients who survived had similar blood glucose levels (P=.01). On multivariable analysis, admission blood glucose was identified as an independent risk factor for death after emergency CABG (P=.01; odds ratio, 1.16; 95% confidence interval, 1.04-1.29). Admission blood glucose was further identified as independently associated with increased risk for a composite outcome of death, postoperative renal failure or stroke (P=.01; odds ratio, 1.14; 95% confidence interval, 1.03-1.27).

CONCLUSIONS

Our study shows for the first time that admission blood glucose is correlated with increased morbidity and mortality among patients undergoing emergency CABG surgery.

The Role of Markers of Low-Grade Inflammation for the Early Time Course of Glycemic Control, Glucose Disappearance Rate, and β-Cell Function in Recently Diagnosed Type 1 and Type 2 Diabetes

OBJECTIVE

Inflammatory processes are involved in the progression of insulin resistance and β-cell dysfunction in individuals with prediabetes and contribute to the development of diabetes. We hypothesized that higher levels of biomarkers of low-grade inflammation are associated with the early progression of recently diagnosed diabetes.

RESEARCH DESIGN AND METHODS

Within the prospective German Diabetes Study, patients with recently diagnosed type 1 (n = 42) and type 2 (n = 94) diabetes underwent detailed metabolic characterization within the first year after diagnosis and 2 years thereafter. Associations between changes in markers of low-grade inflammation with changes in glycemic control, β-cell function, and glucose disappearance rate were assessed using multivariable linear regression analysis. Associations were adjusted for age, sex, BMI, smoking status, and 2-year changes in BMI, smoking status, and glucose-lowering medication.

RESULTS

Patients with type 1 and type 2 diabetes exhibited good glucometabolic control at baseline (mean HbA1c 7.08 ± 1.58% [54 ± 17 mmol/mol] and 6.43 ± 0.98% [47 ± 11 mmol/mol], respectively) and 2 years thereafter (mean HbA1c 7.03 ± 1.20% [53 ± 13 mmol/mol] and 6.62 ± 1.14% [49 ± 13], respectively). Two-year increases of high-sensitivity C-reactive protein, soluble E-selectin (sE-selectin), and soluble intercellular adhesion molecule-1 in type 2 diabetes and of IL-18 in type 1 diabetes were associated with 2-year increases of HbA1c. Additionally, 2-year increases of sE-selectin were associated with 2-year decreases of prehepatic β-cell function in type 2 diabetes (all P < 0.05).

CONCLUSIONS

These data indicate that with the clinical onset of diabetes, low-grade inflammation relates to worsening of glycemia and that endothelial activation may contribute to decreasing β-cell function.

Simple clinical risk score for no-reflow prediction in patients undergoing primary Percutaneous Coronary Intervention with acute STEMI

Objectives:

To identify the STEMI patients at high risk in terms of no-reflow during percutaneous coronary intervention (PCI) with a simple risk score system that can be used before reperfusion.

Methods:

Total 173 patients who had undergone primary or rescue percutaneous coronary intervention following the diagnosis of STEMI, were classified as “no-reflow” developers and “no-reflow” non-developers, during the procedure. The pre-procedural ECGs, laboratory parameters, demographic data, time for the treatment, and the treatment methods were evaluated with univariate analysis. The independent predictors were identified by multivariate logistic regression analysis among the no-reflow risk factors. Using the independent predictors, we developed a simple risk score system proportional to area under the ROC (AUROC) curves.

Results:

The independent predictors of “no-reflow” phenomenon were identified as follows: high values of blood glucose at reference; long symptom-onset-to-balloon-time; and low lymphocyte count. The incidence rates of “no-reflow” in patients with low (0-1), moderate (2-3) and high (4-6) risk factors were 13.3%, 40.0%, and 46.7%, respectively. The risk score system demonstrated a good risk prediction between patients with various risk levels of the development of “no-reflow” with a c-statistics of 0.734 (95% CI 0.654-0.814).

Conclusion:

The development of “no-reflow” which is an adverse event in STEMI treatment can be predicted efficiently by simple clinical risk scoring method.

Cardiac autoimmunity as a novel biomarker, mediator, and therapeutic target of heart disease in type 1 diabetes

Patients with type 1 diabetes (T1D) suffer excess mortality from cardiovascular disease (CVD) that has persisted despite substantial reductions in microvascular complications. Although T1D and type 2 diabetes (T2D) are etiologically distinct, it has generally been assumed that CVD in T1D is "the same disease" as that found in T2D. Here, we review the most recent epidemiological and clinical studies on heart disease in T1D, highlighting differences between CVD in T1D and T2D. In addition, we discuss experimental and clinical evidence for a post-myocardial infarction (MI) autoimmune heart syndrome in T1D, including the development of diagnostic assays which we believe can, for the first time, differentiate between heart disease in T1D and T2D. We postulate that a clinically unrecognized form of chronic myocardial inflammation ("myocarditis") triggered by MI contributes to the poor CVD outcomes in T1D. These findings provide a conceptual shift in our understanding of CVD in T1D and have important diagnostic and therapeutic implications.

Effect of diabetes on scintigraphic infarct size in STEMI patients undergoing primary angioplasty

BACKGROUND

It has been shown that among patients with ST-segment elevation myocardial infarction (STEMI), diabetes is associated with a significantly higher mortality, mainly because of impaired reperfusion. However, few data have been reported so far on infarct size as evaluated by well-refined techniques, such as nuclear imaging techniques. Therefore, the aim of the current study was to investigate the effect of diabetes in infarct size as evaluated by myocardial scintigraphy in a large cohort of STEMI patients undergoing primary PCI.

METHODS

We included 830 STEMI patients undergoing primary PCI. Infarct size was evaluated at 30 days by technetium-99 m-sestamibi. A logistic regression analysis was performed to determine the relation between diabetes and infarct size (as above the median) after correction for baseline confounding factors.

RESULTS

A total of 115 (13.8%) out of 830 patients suffered from diabetes. Diabetic patients were older (p < 0.001), with larger prevalence of female gender (p = 0.006) and hypertension (p = 0.001) but were less often smokers (p = 0.003). Diabetic patients had more often preprocedural thrombolysis in myocardial infarction grade 3 flow (p = 0.034) and less complete ST-segment resolution (p = 0.009). No difference was observed in scintigraphic infarct size between diabetes and control patients (p = 0.6)), which was confirmed at multivariate analysis after correction for baseline confounding factors (Adjusted OR [95% CI] = 0.87 [0.57-1.31, p = 0.51).

CONCLUSION

Our study showed that among STEMI patients undergoing primary angioplasty, diabetes did not affect infarct size as compared with non-diabetic patients.

Metformin: An Old Drug for the Treatment of Diabetes but a New Drug for the Protection of the Endothelium

The anti-diabetic and oral hypoglycaemic agent metformin, first used clinically in 1958, is today the first choice or 'gold standard' drug for the treatment of type 2 diabetes and polycystic ovary disease. Of particular importance for the treatment of diabetes, metformin affords protection against diabetes-induced vascular disease. In addition, retrospective analyses suggest that treatment with metformin provides therapeutic benefits to patients with several forms of cancer. Despite almost 60 years of clinical use, the precise cellular mode(s) of action of metformin remains controversial. A direct or indirect role of adenosine monophosphate (AMP)-activated protein kinase (AMPK), the fuel gauge of the cell, has been inferred in many studies, with evidence that activation of AMPK may result from a mild inhibitory effect of metformin on mitochondrial complex 1, which in turn would raise AMP and activate AMPK. Discrepancies, however, between the concentrations of metformin used in in vitro studies versus therapeutic levels suggest that caution should be applied before extending inferences derived from cell-based studies to therapeutic benefits seen in patients. Conceivably, the effects, or some of them, may be at least partially independent of AMPK and/or mitochondrial respiration and reflect a direct effect of either metformin or a minor and, as yet, unidentified putative metabolite of metformin on a target protein(s)/signalling cascade. In this review, we critically evaluate the data from studies that have investigated the pharmacokinetic properties and the cellular and clinical basis for the oral hypoglycaemic, insulin-sensitising and vascular protective effects of metformin.

Association between hyperglycemia at admission and microvascular obstruction in patients with ST-segment elevation myocardial infarction

BACKGROUND

Blood glucose level at admission in ST-segment elevation myocardial infarction (STEMI) is a predictor of heart failure and mortality. A previous study showed the association between hyperglycemia and microvascular dysfunction using myocardial contrast echocardiography. Late gadolinium enhancement (LGE) cardiovascular magnetic resonance imaging (CMR) can demonstrate microvascular obstruction (MVO) as the area with hypointense core within LGE. This study was performed to investigate the association between hyperglycemia at admission and MVO using CMR in patients with STEMI.

METHODS

Ninety-three patients with first STEMI who were treated by percutaneous coronary intervention (PCI) were included. CMR was performed within 7 days after PCI. Venous blood was collected routinely immediately after admission for plasma glucose determination before intravenous injection of some medications. Samples were analyzed in the hospital's central laboratory. We performed LGE-CMR to assess the presence of MVO.

RESULTS

MVO was found in 34 (37%) of all 93 patients; their glucose level at admission was significantly higher than that of patients who did not exhibit MVO [204 (153-267)mg/dl vs. 157 (127-200)mg/dl, p=0.002]. There were no differences in glycosylated hemoglobin and incidence of diabetes mellitus between the two groups. A multivariable logistic regression analysis showed that glucose level at admission was an independent predictor of MVO (odds ratio, 1.014; 95% confidence interval, 1.004 to 1.023; p=0.006). The glucose level at admission 190mg/dl was the best threshold value for identifying MVO. The occurrence of MVO was significantly higher in the patients with glucose level at admission ≧190mg/dl compared with the patients with glucose level <190mg/dl [18 (53%) vs. 16 (27%), p=0.023].

CONCLUSIONS

Hyperglycemia at admission in STEMI patients who were treated by PCI was associated with the presence of MVO assessed by LGE-CMR.

Rationale for and design of the Acarbose Cardiovascular Evaluation (ACE) trial

Patients with cardiovascular disease and impaired glucose tolerance are at increased risk of cardiovascular events and type 2 diabetes mellitus (T2DM). Lifestyle modification or pharmacological intervention can delay progression to T2DM, but there is no clear evidence that they reduce cardiovascular risk in this population. Acarbose, an α-glucosidase inhibitor that lowers postprandial blood glucose, has been shown to reduce T2DM risk by 25%, and possibly cardiovascular risk in impaired glucose tolerance subjects without cardiovascular disease.

A preliminary study on the variability of blood glucose following meal consumption as it relates to differences in oral glucose tolerance in young adults

Insulin resistance (IR) affects the ability to maintain normal glycemia and places one at greater risk of the development of disease. The aim of this study was to assess IR via the administration of an oral glucose tolerance test (OGTT) and then determine the relationship between IR and postprandial blood glucose levels in young adults 19-24 years of age. Following a 10 hour fast, 10 men and 10 women completed an OGTT and in three subsequent weeks consumed high, medium, and low glycemic load (GL) meals in random order. Fasted and two-hour (2 h) blood glucose levels were determined. Height, weight, and waist circumference were measured and subjects completed a questionnaire recording recent weight gain, family history of diabetes, and physical fitness. Although all fasted blood glucose levels were normal, two subjects classified as impaired glucose tolerant based on 2 h OGTT values >140 mg/dL. OGTT and high glycemic load meal 2 h blood glucose levels were highly significantly correlated (p = 0.0012). Significantly higher blood glucose levels were also found in women, high BMI, low fitness, and rapid weight gain groups. Although limited by a small sample, these preliminary data suggest that glycemic response to meal ingestion is based on both the GL of the meal and the individual's level of IR.

Nutritionally mediated oxidative stress and inflammation

There are many sources of nutritionally mediated oxidative stress that trigger inflammatory cascades along short and long time frames. These events are primarily mediated via NF κ B. On the short-term scale postprandial inflammation is characterized by an increase in circulating levels of IL-6 and TNF- α and is mirrored on the long-term by proinflammatory gene expression changes in the adipocytes and peripheral blood mononuclear cells (PBMCs) of obese individuals. Specifically the upregulation of CCL2/MCP-1, CCL3/MIP-1 α , CCL4/MIP-1 β , CXCL2/MIP-2 α , and CXCL3/MIP-2 β is noted because these changes have been observed in both adipocytes and PBMC of obese humans. In comparing numerous human intervention studies it is clear that pro-inflammatory and anti-inflammatory consumption choices mediate gene expression in humans adipocytes and peripheral blood mononuclear cells. Arachidonic acid and saturated fatty acids (SFAs) both demonstrate an ability to increase pro-inflammatory IL-8 along with numerous other inflammatory factors including IL-6, TNF α , IL-1 β , and CXCL1 for arachidonic acid and IGB2 and CTSS for SFA. Antioxidant rich foods including olive oil, fruits, and vegetables all demonstrate an ability to lower levels of IL-6 in PBMCs. Thus, dietary choices play a complex role in the mediation of unavoidable oxidative stress and can serve to exacerbate or dampen the level of inflammation.

Impact of diabetes on long-term outcome after primary angioplasty: insights from the DESERT cooperation

OBJECTIVE

Diabetes has been shown to be associated with worse survival and repeat target vessel revascularization (TVR) after primary angioplasty. The aim of the current study was to evaluate the impact of diabetes on long-term outcome in patients undergoing primary angioplasty treated with bare metal stents (BMS) and drug-eluting stents (DES).

RESEARCH DESIGN AND METHODS

Our population is represented by 6,298 ST-segment elevation myocardial infarction (STEMI) patients undergoing primary angioplasty included in the DESERT database from 11 randomized trials comparing DES with BMS.

RESULTS

Diabetes was observed in 972 patients (15.4%) who were older (P < 0.001), more likely to be female (P < 0.001), with higher prevalence of hypertension (P < 0.001), hypercholesterolemia (P < 0.001), and longer ischemia time (P < 0.001), and without any difference in angiographic and procedural characteristics. At long-term follow-up (1,201 ± 441 days), diabetes was associated with higher rates of death (19.1% vs. 7.4%; P < 0.0001), reinfarction (10.4% vs. 7.5%; P < 0.001), stent thrombosis (7.6% vs. 4.8%; P = 0.002) with similar temporal distribution--acute, subacute, late, and very late--between diabetic and control patients, and TVR (18.6% vs. 15.1%; P = 0.006). These results were confirmed in patients receiving BMS or DES, except for TVR, there being no difference observed between diabetic and nondiabetic patients treated with DES. The impact of diabetes on outcome was confirmed after correction for baseline confounding factors (mortality, P < 0.001; repeat myocardial infarction, P = 0.006; stent thrombosis, P = 0.007; TVR, P = 0.027).

CONCLUSIONS

This study shows that among STEMI patients undergoing primary angioplasty, diabetes is associated with worse long-term mortality, reinfarction, and stent thrombosis in patients receiving DES and BMS. DES implantation, however, does mitigate the known deleterious effect of diabetes on TVR after BMS.

Oxidative stress and antioxidant status in patients with late-onset gestational diabetes mellitus

The relationship between late-onset gestational diabetes mellitus [GDM] and oxidative stress is not well known, and the importance of the oxidant/antioxidant equilibrium in the clinical evolution and its complications require elucidation. The aim of the study was to evaluate the relationships between maternal levels of markers of oxidative stress in women with late-onset GDM that, potentially, may have considerable clinical implications in the pathogenesis and/or the evolution of GDM. Pregnant women (n = 78; 53 with GDM, 25 controls), between the 24th and 29th week of gestation, were enrolled. Both groups were analysed for demographic data, perinatal and obstetrics outcomes together with the levels of the marker's oxidative stress and antioxidant status. Control versus patient results in the univariate analysis were the following: pre-gestational body mass index [BMI] 23.31 ± 4.2 vs. 27.13 ± 4.6 kg/m(2) (P = 0.001); weeks at delivery 39.2 ± 3.05 vs. 38.9 ± 1.8 (P = 0.09); Caesarean delivery 12.5 vs. 43% (P = 0.004); macrosomia 4 vs. 9.4% (P = 0.6); lipoperoxides [LPO] 2.06 ± 1.00 vs. 3.14 ± 1.55 μmol/mg (P = 0.001); catalase 3.23 ± 1.41 vs. 2.52 ± 1.3 nmol/min/ml (P = 0.03); superoxide dismutase [SOD] 0.11 ± 0.04 vs. 0.08 ± 0.01 U/ml (P = 0.0003); glutathione peroxidase [GPX] 0.03 ± 0.006 vs. 0.025 ± 0.006 nmol/min/ml (P = 0.01); glutathione reductase [GSH] 0.004 ± 0.002 vs. 0.004 ± 0.004 nmol/min/ml (P = 0.9)]; and glutathione transferase [GST] 0.0025 ± 0.0012 vs. 0.0027 ± 0.00017 nmol/min/ml (P = 0.7). Multivariate analysis showed catalase might have a protective effect against GDM development and LPO seems to be a risk factor for the disease. These data suggest an increase in oxidative stress and a decrease in antioxidative defence in women with late-onset GDM and, as such, may have considerable clinical implications in the pathogenesis and/or the course of the pregnancy in these patients.

Relationship of thrombus characteristics to the incidence of angiographically visible distal embolization in patients with ST-segment elevation myocardial infarction treated with thrombus aspiration

OBJECTIVES

This study sought to investigate the association between pathological characteristics of aspirated intracoronary thrombi and the incidence of angiographically visible distal embolization (AVDE) during primary percutaneous coronary intervention (p-PCI) in patients with ST-segment elevation myocardial infarction (STEMI) treated with thrombus aspiration.

BACKGROUND

AVDE of atherosclerotic and thrombotic material has been shown to impair myocardial perfusion and contribute to poor clinical outcome in patients with STEMI. Recent studies have shown that thrombus composition and size are associated with the incidence of AVDE.

METHODS

Aspirated thrombi from 164 STEMI patients within 12 h of symptom onset were investigated immunohistochemically using antibodies against platelets, erythrocytes, and inflammatory cells.

RESULTS

The angiographic results showed that AVDE during p-PCI occurred in 22 (13.4%) patients. Pathological analysis revealed that thrombi from patients with AVDE had a greater erythrocyte-positive area (60 ± 15% vs. 43 ± 21%, p < 0.0005) and more myeloperoxidase-positive cells (943 ± 324 cells/mm(2) vs. 592 ± 419 cells/mm(2), p < 0.0005) than those from patients without AVDE. Thrombus size, quantified as the thrombus surface area, was positively correlated with the erythrocyte component (r = 0.362, p < 0.0001). Moreover, multivariate logistic analysis demonstrated that erythrocyte-positive area in the thrombi, glucose levels on admission, larger vessel diameter (≥ 3.5 mm), and pre-balloon dilation were independent predictors of the incidence of AVDE.

CONCLUSIONS

This study demonstrated that the erythrocyte-rich component of aspirated thrombi may be associated with the incidence of AVDE during p-PCI in patients with STEMI.