An association of serum vistafin level and number of circulating endothelial progenitor cells in type 2 diabetes mellitus patients

BackgroundThe decreased number and impaired functions of endothelial progenitor cells (EPCs) may associate with cardiovascular disease (CV) including atherosclerosis. However, the role of vistafin in regulation of angiogenic EPC subset maturation in T2DM patients without known atherosclerosis is still not fully understood.The aim of the studyTo investigate an association of serum vistafin level and number of circulating EPCs in T2DM patients beyond known CV disease.MethodsThis case–control observational investigation was evolved 54 subjects with T2DM and 35 healthy volunteers. The flow cytometry was used for predictably distinguishing cell subsets, which depend on expression of CD45, CD34, CD14, Tie-2, and VEGFR2. Biomarkers were measured at baseline of the study.ResultsAll T2DM patients were divided depending median of vistafin level (5.88 ng/mL) in to two cohorts with low vistafin level (<5.88 ng/mL; n = 29) and high vistafin level (≥5.88 ng/mL; n = 25) respectively. Logistic regression analysis has shown that visfatin, hs-CRP, age and BMI were the best variables in the prediction of EPC number labeled as CD14⁺CD309⁺ and CD14⁺CD309⁺Tie²⁺ cells. After adjustment of the model to age and BMI elevated visfatin level remained the best predictor for both CD14⁺CD309⁺ and CD14⁺CD309⁺Tie²⁺ EPCs (OR 0.92, 95% CI: 0.88–0.95; P = 0.001 and OR 0.90, 95% CI: 0.87–0.96; P = 0.001 respectively).ConclusionWe found that elevated level of vistafin was an independent predictor for declined numerous of non-classical EPCs labeled as CD14⁺CD309⁺ and CD14⁺CD309⁺Tie²⁺, whereas CD34⁺ subsets of EPCs did not associate with vistafin level in T2DM individuals.     

Diverse contribution of bone marrow-derived late-outgrowth endothelial progenitor cells to vascular repair under pulmonary arterial hypertension and arterial neointimal formation

AimsIt is still controversial whether bone marrow (BM)-derived endothelial progenitor cells (EPCs) can contribute to vascular repair and prevent the progression of vascular diseases. We aimed to characterize BM-derived EPC subpopulations and to evaluate their therapeutic efficacies to repair injured vascular endothelium of systemic and pulmonary arteries.Methods and resultsBM mononuclear cells of Fisher-344 rats were cultured under endothelial cell-conditions. Early EPCs appeared on days 3–6. Late-outgrowth and very late-outgrowth EPCs (LOCs and VLOCs) were defined as cells forming cobblestone colonies on days 9–14 and 17–21, respectively. Among EPC subpopulations, LOCs showed the highest angiogenic capability with enhanced proliferation potential and secretion of proangiogenic proteins. To investigate the therapeutic effects of these EPCs, Fisher-344 rats underwent wire-mediated endovascular injury in femoral artery (FA) and were concurrently injected intraperitoneally with 60 mg/kg monocrotaline (MCT). Injured rats were then treated with six injections of one of three EPCs (1 × 10⁶ per time). After 4 weeks, transplanted LOCs, but not early EPCs or VLOCs, significantly attenuated neointimal lesion formation in injured FAs. Some of CD31⁺ LOCs directly replaced the injured FA endothelium (replacement ratio: 11.7 ± 7.0%). In contrast, any EPC treatment could neither replace MCT-injured endothelium of pulmonary arterioles nor prevent the progression of pulmonary arterial hypertension (PAH). LOCs modified protectively the expression profile of angiogenic and inflammatory genes in injured FAs, but not in MCT-injured lungs.ConclusionBM-derived LOCs can contribute to vascular repair of injured systemic artery; however, even they cannot rescue injured pulmonary vasculature under MCT-induced PAH.     

Relationship between circulating endothelial progenitor cells and insulin resistance in non-diabetic patients with ischemic chronic heart failure

AimThe objective of this study was to assess a relationship between insulin resistance (IR) and counts of CD45⁻CD34⁺, CD14⁺CD309⁺, and CD14⁺CD309⁺Tie2⁺ phenotyped circulating endothelial progenitor cells (EPCs) in patients with ischemic chronic heart failure (CHF).MethodsThe study involved 300 CHF patients (186 males) aged 48–62 years with angiografically proven coronary artery disease and/or previously defined myocardial infarction. Insulin resistance was assessed by the homeostasis model assessment for insulin resistance (HOMA-IR). EPC populations were phenotyped by flow cytofluorimetry.ResultsCirculating EPCs counts were statistically significantly lower in CHF patients with IR than in patients without IR. We found that the most valuable multivariable predictors of the depletion of the CD45⁺CD34⁺ EPCs were NT-pro-brain natriuretic peptide (BNP) (1.32; 95% CI = 1.19–2.77; P = 0.001), left ventricular ejection fraction (OR = 1.30; 95% CI = 1.09–1.60; P = 0.002), NYHA class (OR = 1.12; 95% CI = 1.02–1.19; P = 0.001). NT-pro-BNP (OR = 1.45; 95% CI = 1.15–2.90; P = 0.003), left ventricular ejection fraction (OR = 1.32; 95% CI = 1.11–1.65; P = 0.001) were found as powerful predictors for depletion in CD45⁻CD34⁺ EPCs. We also identified six independent variables with high predictive value for depletion of CD14⁺CD309⁺ EPCs: NT-pro-BNP (OR = 1.41; 95% CI = 1.15–2.90; P = 0.003), left ventricular ejection fraction (OR = 1.18; 95% CI = 1.10–1.76; P = 0.036), NYHA class (OR = 1.15; 95% CI = 1.07–1.22; P = 0.001), hs-C reactive protein (OR = 1.02; 95% CI = 1.01–1.05; P = 0.012). As independent multivariable predictors for depletion in CD14⁺CD309⁺Tie2⁺ EPCs were selected five variables: NT-pro-BNP (OR = 1.65; 95% CI = 1.44–4.70; P = 0.006), left ventricular ejection fraction (OR = 1.07; 95% CI = 1.02–1.12; P = 0.018), NYHA class (OR = 1.13; 95% CI = 1.06–1.21; P = 0.001), hs-C-reactive protein (OR = 1.08; 95% CI = 1.03–1.16; P = 0.002).ConclusionIR may be an additional factor contributing decreased circulating level of proangiogenic EPCs in non-diabetic CHF patients.     

Differential expression of Toll-like receptor 4 and human monocyte subsets in acute myocardial infarction

ObjectiveTo investigate the involvement of Toll-like receptor 4 (TLR4) expression on two monocyte subsets in the pathologic processes related to acute coronary syndrome. How monocytes, which have recently been shown to comprise two distinct subsets, mediate the process of coronary plaque rupture remains to be fully elucidated. Recent studies have shown that TLR4 is involved in monocyte activation of patients with accelerated forms of atherosclerosis.MethodsWe enrolled 65 patients with acute myocardial infarction (AMI, n = 22), unstable angina pectoris (UAP, n = 16), and stable angina pectoris (SAP, n = 27) who underwent coronary angiography and 15 healthy controls. The expression of TLR4 on two monocyte subsets (CD14⁺CD16^? and CD14⁺CD16⁺) was measured by flow cytometry.ResultsIn patients with AMI, TLR4 was more expressed on circulating CD14⁺CD16⁺ monocytes than on CD14⁺CD16^? monocytes (p < 0.001). The expression levels of TLR4 on CD14⁺CD16⁺ monocytes were significantly elevated in patients with AMI compared with other 3 groups. TLR4 expression levels on CD14⁺CD16⁺ monocytes were significantly elevated at the culprit site compared with the systemic level (p = 0.044). The up-regulation of TLR4 on admission was remarkably decreased 12 days after AMI (p < 0.001). In addition, plasma levels of tumor necrosis factor-α were positively correlated with TLR4 expression levels on monocytes in patients with AMI (r = 0.47, p = 0.027).ConclusionTLR overexpression on CD14⁺CD16⁺ monocytes in AMI, as demonstrated both in the circulation and at the coronary culprit site, might be associated with the pathogenesis of AMI.     

Diosgenin ameliorates palmitate-induced endothelial dysfunction and insulin resistance via blocking IKKβ and IRS-1 pathways

AimAtherosclerotic renovascular disease (ARVD) may impair renal function and increase cardiovascular morbidity and mortality, but the mechanism by which ARVD impacts cardiovascular function is unclear. We tested the hypothesis that preservation of renal function can reverse cardiac dysfunction in ARVD.Methods and resultsEndothelial progenitor cells (EPC) were injected intra-renally (ARVD + EPC) after 6 weeks of swine ARVD (concurrent hypercholesterolemia and renovascular hypertension), and single-kidney function and myocardial blood-flow and microvascular permeability (MP) responses to adenosine were assessed using CT 4 weeks later. Myocardial microvascular density was evaluated by micro-CT. Inflammation and oxidative-stress were assessed in kidney venous and systemic blood samples. Normal and untreated ARVD pigs served as controls.Blood pressure was similarly increased in ARVD and ARVD + EPC. Compared to normal, ARVD showed lower glomerular filtration rate, elevated renal vein and systemic oxidized LDL (ox-LDL), aldosterone, uric acid, isoprostanes, transforming growth factor (TGF)-β, and interleukine-6. Renal vein ox-LDL and TGF-β showed a positive gradient across the stenotic kidney, indicating increased renal oxidative stress and fibrogenic activity. Furthermore, ARVD impaired myocardial blood-flow and MP response to adenosine, decreased microvascular density, and induced myocardial fibrosis. Improvement of renal function in ARVD + EPC decreased systemic aldosterone, inflammation, and oxidative stress, and improved myocardial microvascular integrity and density.ConclusionSelective improvement in renal function, which reduced renal and systemic oxidative stress and inflammation, preserved remote myocardial microvascular function and architecture, despite enduring hypertension. These findings underscore functionally important cardiorenal crosstalk possibly mediated by renal injury signals.     

Renal safety of intensive cholesterol-lowering treatment with rosuvastatin: a retrospective analysis of renal adverse events among 40,600 participants in the rosuvastatin clinical development program

ObjectiveIntensive lowering of low-density lipoprotein cholesterol (LDL-C) with statins reduces cardiovascular risk but can cause liver-, muscle-, and possibly renal-related adverse events (AEs). We assessed the effects of rosuvastatin on the risk of developing renal impairment or renal failure among participants in the rosuvastatin clinical development program.MethodsThe analysis was based on AE data reported by investigators from 36 studies that included 40,600 participants who did not have advanced, pre-existing renal disease. Rates of renal AEs were determined based on time to first occurrence of renal impairment or renal failure.ResultsRenal impairment or renal failure was reported in 536 study participants during 72,488 patient-years of follow-up. Renal event rates were higher in patients with history of heart failure (n = 5011), hypertension (n = 21,864), diabetes (n = 5165), or estimated glomerular filtration rate (eGFR) <60 ml/min/1.73 m² (n = 9507) at baseline but did not differ with rosuvastatin compared with placebo or with rosuvastatin 40 mg compared with rosuvastatin 10 mg. Relative risk (RR) estimates obtained from pooled analysis of placebo-controlled trials were RR: 1.03 (95% CI: 0.86–1.23, p = 0.777) for any reported renal impairment or renal failure event, RR: 1.02 (95% CI: 0.76–1.37, p = 0.894) for serious renal AEs, and RR: 0.70 (95% CI: 0.36–1.35, p = 0.282) for renal AEs leading to death.ConclusionThese findings suggest that intensive LDL-C-lowering treatment with rosuvastatin does not affect the risk of developing renal insufficiency or renal failure in patients who do not have advanced, pre-existing renal disease.     

Circulating endothelial and platelet derived microparticles reflect the size of myocardium at risk in patients with ST-elevation myocardial infarction

ObjectivesMicroparticles (MP) are small membrane vesicles, released from activated, damaged and apoptotic endothelial cells (EMP) or platelets (PMP) that may actively modulate inflammation, coagulation and vascular function. We tested the hypothesis that the number of circulating EMP or PMP in acute myocardial infarction correlates with the myocardium at risk (MaR) and infarct size (IS).MethodsEMP were quantified in plasma samples of 36 patients (age: 63 ± 10 years) with first time ST-elevation myocardial infarction (STEMI) using flow cytometry. EMP were defined as CD31⁺/CD42^? MP and CD144⁺ MP and PMP as CD31⁺/CD42⁺ MP. MaR and IS was determined by cardiovascular magnetic resonance imaging one week after the index event.ResultsPlasma levels of CD31⁺/CD42^? EMP were 251.0 ± 178.8/μl and CD144⁺ 106.3 ± 33.7/μl. PMP levels were 579.2 ± 631.8/μl. MaR was 31.0 ± 11.2% of the left ventricle and IS was 11.4 ± 7.1% of the left ventricle. Patients with STEMI in the left anterior descending artery had higher levels of CD31⁺/CD42^? EMP and PMP than those with other infarct-related arteries (p < 0.05). The numbers of CD31⁺/CD42^? EMP and PMP correlated to MaR, but not to IS.ConclusionsCirculating EMP and PMP correlate to the size of MaR in patients with STEMI suggesting that they reflect the severity of the endothelial injury and platelet activation during myocardial ischemia.     

Inverse Correlation Between Circulating Endothelial Progenitor Cells With CD34+CD133+ and the Severity of Coronary Atherosclerosis Assessed by Syntax Score

BackgroundThe number of endothelial progenitor cells (EPCs) descends when atherosclerosis developed. The objective was to compare the number of CD34 + CD133 + cells with the severity of atherosclerosis assessed by Syntax score.MethodsThe study included 80 patients with stable angina undergoing coronary angiography. Patients were classified into single-vessel group, multiple-vessel group and normal group according to angiography. The percentage of CD34 + CD133 + cells in the mononuclear cells isolated from peripheral blood of different groups by flow cytometric analysis was compared. The quantity of CD34 + CD133 + EPCs was log transformed to improve normality (lgEPC). Syntax score was used in this study to assess the extent of coronary artery disease.Results:The level of lgEPC was lower in the single-vessel group than that in the normal group (− 3.42 ± 0.44 versus − 3.17 ± 0.39, P < 0.05), and the level of lgEPC was lower in the multiple-vessel group than that in the single vessel group (− 3.63 ± 0.31 versus − 3.42 ± 0.44, P < 0.05). An inverse correlation between lgEPC and Syntax score analyzed by linear regression.ConclusionsEPC level probably serves as a predictor of the development and severity of atherosclerosis on a cellular level. EPC, a relatively more important risk factor, perhaps protects against coronary artery disease.     

Dynamics of endothelial progenitor cells in patients with advanced hepatocellular carcinoma

Background and aimsCirculating endothelial progenitor cells (EPC) predict tumor vascularization and disease progression, but limited information is available on their dynamics in hepatocellular carcinoma (HCC) undergoing systemic treatment.MethodsWe prospectively analyzed different populations of EPC in 16 patients with advanced HCC receiving sorafenib. Patients were studied before therapy (T0, n = 16) and after two (T2, n = 12) and eight weeks (T8, n = 8), using high-performance flow-cytometry. The tumor response at T8 was categorized as progressive disease (PD) or clinical benefit (CB, all other responses).ResultsAt T0, higher levels of CD34⁺CD133⁺KDR⁺ and CD34⁺KDR⁺ were observed in patients with alpha-fetoprotein ≥400 ng/ml or non-viral liver disease, whereas CD34⁺CD133⁺KDR⁺ cells were virtually absent in patients with vascular invasion. CD34⁺KDR⁺ and CD34⁺CD133⁺KDR⁺ were directly correlated with platelet count. Frequencies of all populations of EPC declined in patients receiving sorafenib. Levels of CD34⁺CD133⁺ were higher at T0 in patients with CB compared to patients with PD. In patients belonging to the CB group CD34⁺KDR⁺ cells at T0 were directly correlated to platelet count.ConclusionIn patients with advanced HCC, EPC are directly correlated with platelet count, suggesting a common activation of selected bone marrow pathways. Levels of a CD34⁺KDR⁺ are higher at baseline in patients responding to sorafenib.     

Endothelin-1 levels predict endothelial progenitor cell mobilization after acute myocardial infarction

IntroductionEndothelin-1 (ET-1), circulating endothelial cells (CEC) and endothelial progenitor cells (EPC) are well-known modulators of endothelial function with important cardiac effects after an acute myocardial infarction. However, the relationship between them has never been assessed.The objective of the present study was to establish the relationship between ET-1, CEC, and EPC concentrations after ST-elevation myocardial infarction (STEMI).MethodsEndothelin-1, CEC, and EPC levels were measured in 61 patients presenting with a first STEMI. Samples were withdrawn acutely 6–24 h and 1 week after admission. Assessments included reperfusion outcomes (angiography), left ventricular ejection fraction (echocardiography), and 30-day mortality.ResultsMean age was 60.6 ± 12.6 years and 45 (74%) were males. Higher ET-1 plasma levels were associated with lower EPC count after 1 week (7.45 ± 2.53 pg/ml if EPCs in the first quartile vs 5.72 ± 1.49 pg/ml if EPCs in the fourth quartile; P = 0.04).In contrast with CEC and EPC count, higher ET-1 concentrations on admission were associated with Killip ≥ 2 (9.92 ± 2.01 pg/ml vs 7.32 ± 2.13 pg/ml; P < 0.001), post-reperfusion thrombolysis in myocardial infarction (TIMI) < 3 (8.65 ± 2.86 pg/ml vs 5.87 ± 1.93 pg/ml; P = 0.002), myocardial blush grade (MBG) < 3 (7.46 ± 2.48 pg/ml vs 5.99 ± 2.01 pg/ml; P = 0.004) and higher 30-day mortality (10.29 ± 2.02 pg/ml vs 6.57 ± 2.20 pg/ml; P = 0.005).ConclusionsIn STEMI patients, high ET-1 levels on admission predict a lower EPC mobilization after 1 week. Endothelin-1 provides better clinical, angiographic and echocardiographic information for prognosis than do CEC and EPC concentrations.     

Mobilization,endothelial differentiation and functional capacity of endothelial progenitor cells after ischemic stroke

Endothelial progenitor cells (EPCs) have introduced new possibilities for cell-based vasculogenesis treatment after stroke. In this study we quantified circulating levels of EPCs in stroke patients and in healthy controls, and evaluated the potential of EPCs to induce vasculogenesis in vitro. Blood was drawn from tPA-treated stroke patients and control subjects, and the circulating EPCs levels in each group were quantified by flow cytometry and cell culture assays. Immunophenotyping was performed using multiple markers (UEA-lectin, CD133, vWF and KDR) and tubulogenic function was assessed with the Matrigel® assay. The produced angiogenic factors were quantified by multiple ELISA and RT-PCR. Fluorescence-activated cell sorting (FACS) revealed higher levels of circulating CD133+/CD34+/KDR+/CD45+ cells in the acute strokes as compared to the control subjects (p = 0.02). On the other hand, more EPCs grew in cell culture from subacute strokes (p = 0.016) than from controls. The endothelial and progenitor lineages of the EPCs were confirmed by immunophenotyping. Interestingly, the appearance of outgrowth EPCs (OECs) correlated positively to stroke severity (p = 0.013). Finally, greater capacity to induce vasculogenesis in vitro was found in EPCs from subacute strokes (p = 0.03), which we attribute to a higher expression and secretion of angiogenic factors. Our results suggest an early EPC mobilization but an enhanced angiogenic function in the subacute phase of stroke. Nonetheless, development of cell-based therapy for stroke will require further studies to identify those EPCs with the greatest therapeutic potential.     

Potential Link Between C3a,C3b and Endothelial Progenitor Cells in Resistant Hypertension

IntroductionEndothelial progenitor cells (EPC) and complement C3 are involved in the pathophysiology of arterial hypertension. C3a is the negative regulator of progenitor cells egress during their mobilization from bone marrow. Previously, higher plasma concentration of C3 was observed in resistant arterial hypertension (RAH) than in controlled arterial hypertension (CAH). Thus, we hypothesized that RAH would be associated with complement C3 activation and reduced number of circulating EPCs.ObjectiveTo compare C3a, C3b and their correlation with circulating EPC in subjects with RAH and CAH.MethodsBlood pressure was measured by electronic sphygmomanometer. EPCs were identified as CD34+/CD133+/KDR+ cells by flow cytometry. C3a and C3b were determined using enzyme-linked immunosorbent assay (Quidel, CA).ResultsRAH group (n = 20) and CAH group (n = 20) and 17 healthy individuals (control group) were recruited. In the RAH group, C3a (858.1 ± 70.6 μg/dL) was higher than in the CAH group (816.1 ± 123.3 μg/dL; P < 0.001), and in the control group (751.3 ± 98.8; P < 0.001), C3b (564.1 ± 54.7 μg/dL) was higher than in the CAH group (490.2 ± 58.5 μg/dL; P < 0.001). In control group (456.3 ± 98.8; P < 0.001), statistically significant negative correlation was observed between C3a and blood levels of EPC (r = ?0.523, P = 0.018); statistically significant positive correlation was observed between systolic blood pressure and blood levels of C3a (r = 0.52, P = 0.02) and between systolic blood pressure and blood levels of C3b (r = 0.57, P = 0.009).ConclusionRAH is characterized by higher levels of C3 component fragments and a negative correlation between circulating C3a and EPCs.     

Salt and the metabolic syndrome

Background and aimsHigh blood pressure in subjects with the metabolic syndrome (MS) is largely related to dietary salt. We investigated in free-living men and women whether increase in dietary salt intake is associated with the presence and severity of the MS.Methods and resultsA total of 766 subjects (251M, 515F) of 44.9 ± 0.5 years/age and SBP/DBP of 120 ± 0.6/77 ± 0.4 mmHg were studied. Twenty-four hour urinary sodium (UNa⁺) and potassium (UK⁺) excretions were 143±2.5 mmol (median: 131.5) and 48 ± 0.9 mmol (median: 44). UNa⁺ was higher in men than in women (median: 155.5 vs. 119.8 mmol/day; P < 0.0001). UK⁺ (r = 0.34; P < 0.0001), measures of obesity (r = 0.26; P < 0.0001) and BP (r = 0.15; P < 0.0001) were significantly associated with UNa⁺. The association with BP was lost after adjusting for weight.Of the 766 subjects, 256 (33.4%) met the NCEP-ATPIII criteria for the MS. Median UNa⁺ in men and women with no traits of the MS was 140 and 116.7 mmol/day, respectively (P < 0.001), increasing to 176 in men and 135 mmol/day in women with 4–5 components of the syndrome (P < 0.001). Weight, BMI and waist increased significantly across the quartiles of UNa⁺ both in men and women; whereas, age, lipids and fasting glucose did not. SBP and DBP were associated with UNa⁺ in men but not in women. UK⁺ correlated with age in men and women (r = 023; P < 0.0001) and with obesity in women (r = 0.14; P = 0.001).ConclusionsUNa⁺ a measure of dietary sodium intake in free-living subjects was markedly increased in subjects with the MS. Higher UNa⁺ was associated with obesity and higher BP, but not with age, dyslipidemia or fasting glucose.     

A combination of secondhand cigarette smoke and Chlamydia pneumoniae accelerates atherosclerosis

ObjectiveSecondhand smoke (SS) induces chronic infection of endothelial cells by Chlamydia pneumoniae (Cpn) in vitro. We investigated the in vivo effect on atherosclerosis following exposure to SS and infection with Cpn both independently and in combination in ApoE?/? mice.Methods and resultsPlaques were largest in the combined SS + Cpn-exposed mice with 12–57% greater cross-sectional area compared with all other groups (P < 0.03). Quantitative RT-PCR (qRT-PCR) from aortic roots revealed a synergistic upregulation of both OX40L (CD134L) and MyD88 in SS + Cpn mice (P < 0.05). This upregulation occurred despite decreased numbers of macrophage, dendritic cell, CD4 T cell and smooth-muscle-cell infiltrates as determined by quantitative IHC and qRT-PCR. To elucidate whether enhanced apoptosis correlated with reduced plaque cellularity, area of Tdt-mediated dUTP nick labeling positive (TUNEL+) cells and expression of key bridging molecules necessary for efferocytosis (Mertk, Tgm2, FasL and C1qa) were examined. In SS + Cpn mice, there was an increase of the area of TUNEL+ cells in plaque cores (P < 0.001) and a downregulation of efferocytosis gene expression (P < 0.05). Systemic expression of cytokines in sera (Luminex) showed no differences between groups, suggesting that focal disease mechanisms within the plaque predominated.ConclusionsThe combination of SS exposure and Cpn infection enhanced atherosclerosis more than either variable did independently by activating inflammatory cells and by promoting growth and maturation of lesions via defective phagocytic clearance and accumulation of apoptotic cells.     

Rosuvastatin improves basal nitric oxide activity of the renal vasculature in patients with hypercholesterolemia

ObjectiveImpaired endothelium-dependent vasodilation represents an early manifestation of atherosclerosis. Prospective studies have demonstrated that impaired endothelial function in the peripheral circulation of hypercholesterolemic patients predicts CV events and can be restored by statin treatment. Whether this also holds true in the renal circulation has not yet been adequately addressed.MethodsIn a double-blind, randomized, placebo-controlled cross-over trial, 40 hypercholesterolemic patients were randomly assigned to receive rosuvastatin (10 mg/day) and matching placebo. The primary objective of the study was to assess the effect of 6-week treatment with rosuvastatin on basal NOS activity of the renal vasculature, as assessed by measuring renal plasma flow (RPF) both before and after blockade of NOS with systemic infusion of N^G-monomethyl-l-arginine (l-NMMA). In a subgroup of 20 patients we also studied the effects of a 3-day treatment regimen.ResultsCompared to placebo treatment, rosuvastatin decreased LDL-cholesterol levels both after 3 days and 6 weeks of treatment. The decrease in RPF in response to l-NMMA was significantly more pronounced after 6-week therapy with rosuvastatin compared to placebo (?13.7 ± 1.0% versus ?11.3 ± 0.7%; p = 0.046), indicating increased basal NOS activity with rosuvastatin treatment. A trend towards improved basal NOS activity was already evident after 3-day treatment.ConclusionTreatment with rosuvastatin improved basal NOS activity in the renal circulation of hypercholesterolemic patients, suggestive of a nephroprotective effect. In view of the close relation between altered renal function and cardiovascular events, these nephroprotective effects may contribute to the improved CV prognosis associated with statin treatment.     

Study of CD4+, CD8+, and natural killer cells (CD16+, CD56+) in children with immune thrombocytopenic purpura

Objective/backgroundTo assess the percentage of CD4⁺, CD8⁺, and natural killer cells (CD16⁺, CD56⁺) in children with immune thrombocytopenic purpura (ITP) at presentation and study their impact on disease chronicity.MethodsThis case–control study was conducted at the Pediatric Hematology and Oncology Unit, Menoufia University Hospital (tertiary care center in Egypt). The study was held on 30 children presenting with ITP; they were followed-up and classified into two groups: 15 children with acute ITP; and 15 children with chronic ITP. Patients were compared to a group of 15 healthy children of matched age and sex. Measurements of CD4⁺, CD8⁺, and natural killer cells (CD16⁺, CD56⁺) by flow cytometry were assessed and compared in these groups.ResultsCD4⁺ and CD4⁺/CD8⁺ were significantly lower in acute and chronic patients than the control group (p < 0.05 and p < 0.001, respectively), with no significant difference between acute and chronic patients (p > 0.05). However, CD8⁺ was significantly higher in acute and chronic patients than the control group (p < 0.05), with no significant difference between acute and chronic patients (p > 0.05). Natural killer cell percent was significantly lower in acute patients than the control group (p < 0.001), with no significant difference between chronic and control groups (p > 0.05).ConclusionITP is associated with immunity dysfunction denoted by the increase in cytotoxic T lymphocytes and the decrease in natural killer cells.     

Long term efficacy and safety of allopurinol and azathioprine or 6-mercaptopurine in patients with inflammatory bowel disease

Background and aimsWe previously reported that IBD patients who are non-responders to thiopurines with preferential shunting of metabolites to hepatotoxic 6-methylmercaptopurine ribonucleotides compared to 6-thioguanine nucleotides can reverse the ratio of 6-MMP/6-TGN and respond to thiopurines with the addition of allopurinol. The objective of this study is to report long term efficacy and safety, along with results for an additional 11 patients.MethodsRetrospective chart review of patients at the University of Chicago IBD Center treated with allopurinol in addition to thiopurines.ResultsTwenty five patients with Crohn's disease or ulcerative colitis were enrolled. Within the first month of therapy 6-TGN metabolite levels increased from a mean of 186.5 ± 17.4 (SE) to 352.8 ± 37.8 pmol/8 × 10⁸ (p = 0.0001). Over the same period 6-MMP levels decreased from a mean of 11,966 ± 1697 to 2004 ± 536 pmol/8 × 10⁸ (p < 0.0001). The mean daily dosage of prednisone decreased from 19.8 ± 3.8 mg to 5.3 ± 2.7 mg (p = 0.03). Thirteen patients have a minimum of one year follow-up. Nine of these thirteen patients have continued on therapy for at least 2 years. All thirteen of these patients continue to be in clinical remission at the last follow-up visit. No patients have had evidence of sustained thrombocytopenia or abnormal liver enzymes.ConclusionsIn AZA/6-MP non-responders with increased 6-MMP/6-TGN ratios, addition of allopurinol continues to demonstrate safety and efficacy for long-term maintenance and steroid-sparing in IBD.     

PKA-mediated eNOS phosphorylation in the protection of ischemic preconditioning against no-reflow

ObjectiveTo investigate whether ischemic preconditioning (IP) can reduce myocardial no-reflow by activating endothelial (e-) nitric oxide synthase (NOS) via the protein kinase A (PKA) pathway.Methods and ResultsIn a 90-min ischemia and 3-h reperfusion model, minipigs were assigned into sham, ischemia–reperfusion (IR), IR + IP, IR + IP + L-NNA (an eNOS inhibitor, 10 mg·kg^? 1), IR + IP + H-89 (a PKA inhibitor, 1.0 μg·kg^? 1·min^? 1), IR + L-NNA, and IR + H-89 groups. IP pretreatment improved cardiac function and coronary blood flow, decreased the activities of creatine kinase by 36.6% after 90 min of ischemia and by 32.8% after 3 h of reperfusion (P < 0.05), reduced the no-reflow areas from 49.9% to 11.0% (P < 0.01), and attenuated the infarct size from 78.2% to 35.4% (P < 0.01). IP stimulated myocardial PKA activities and the expression of PKA and Ser¹³³ phosphorylated (p-) cAMP response element-binding protein (CREB) in the reflow and no-reflow myocardium, and enhanced the activities of constitutive NOS and the phosphorylation of eNOS at Ser¹¹⁷⁹ and Ser⁶³⁵ in the no-reflow myocardium. IP suppressed the expression of tumor necrosis factor-α and P-selectin, and attenuated cardiomyocytes apoptosis by regulating the expression of Bcl-2 and caspase-3 in the reflow and no-reflow myocardium. The eNOS inhibitor L-NNA completely canceled these beneficial effects of IP without any influence on PKA activity, whereas the PKA inhibitor H-89 partially blocked the IP cardioprotective effects and eNOS phosphorylation at the same time.ConclusionIP attenuates myocardial no-reflow and infarction after ischemia and reperfusion by activating the phosphorylation of eNOS at Ser¹¹⁷⁹ and Ser⁶³⁵ in a partly PKA-dependent manner.     

Single nucleotide polymorphism on chromosome 9p21 and endothelial progenitor cells in a general population cohort

ObjectiveRecent studies have revealed that sequence variation on chromosome 9p21 is a major genetic determinant for coronary heart disease and stroke, however, the underlying mechanism remains unknown. This genomic region contains the gene encoding cyclin-dependent kinase 2A, a regulator of proliferation and differentiation of endothelial progenitor cell (EPC) which has been implicated in vascular repair and protection against cardiovascular disease. We investigated whether carriers and non-carriers of the chromosome 9p21 variation differed in their number and function of EPCs.MethodsWe genotyped a cohort of 769 individuals (who participated in the Bruneck Study) for the single nucleotide polymorphism rs1333049 on chromosome 9p21 and determined circulating EPC numbers and EPC colony formation units (n = 538 and 512, respectively).ResultsThere was no evidence of reduced EPC numbers or colony formation units in carriers of the chromosome 9p21 risk variant. On the contrary, circulating EPC numbers and colony formation units tended to be higher in carriers of the variant (p = 0.189 for EPC numbers and p = 0.190 for EPC colony formation units).ConclusionThese results indicate that the chromosome 9p21 variant does not influence the risk of coronary heart disease and stroke through an effect on circulating EPCs.     

Non-lipid effects of rosuvastatin-fenofibrate combination therapy in high-risk Asian patients with mixed hyperlipidemia

ObjectiveThe aim of this study is to compare the non-lipid effects of rosuvastatin–fenofibrate combination therapy with rosuvastatin monotherapy in high-risk Asian patients with mixed hyperlipidemia.MethodsA total of 236 patients were initially screened. After six weeks of diet and life style changes, 180 of these patients were randomly assigned to receive one of two regimens: rosuvastatin 10 mg plus fenofibrate 160 mg or rosuvastatin 10 mg. The primary outcome variables were the incidences of muscle or liver enzyme elevation. The patients were followed for 24 weeks during drug treatment and for an additional four weeks after drug discontinuation.ResultsThe rates of the primary outcome variables were similar between the two groups (2.8% and 3.9% in the combination and the rosuvastatin groups, respectively, p = 1.00). The combination group had more, but not significantly, common treatment-related adverse events (AEs) (13.3% and 5.6%, respectively) and drug discontinuation due to AEs (10.0% and 3.3%, respectively) than the rosouvastatin group. Combination therapy was associated with higher elevations in homocysteine, blood urea nitrogen, and serum creatinine, whereas elevation in alanine aminotransferase was greater in the rosuvastatin group. Leukocyte count and hemoglobin level decreased to a greater extent in the combination group. The combination group showed greater reductions in TG and elevation in HDL-cholesterol.ConclusionIn our study population, the rosuvastatin–fenofibrate combination resulted in comparable incidences of myo- or hepatotoxicity as rosuvastatin monotherapy. However, this combination may need to be used with caution in individuals with underlying pathologies such as renal dysfunction (NCT01414803).