Endothelial Progenitor Cells: An Appraisal of Relevant Data from Bench to Bedside.

The mobilization of endothelial progenitor cells (EPCs) into circulation from bone marrow is well known to be present in several clinical settings, including acute coronary syndrome, heart failure, diabetes and peripheral vascular disease. The aim of this review was to explore the current literature focusing on the great opportunity that EPCs can have in terms of regenerative medicine.

Clinical correlates of complicated grief among individuals with acute coronary syndromes.

OBJECTIVE: The study aimed at exploring bereavement and complicated grief (CG) symptoms among subjects without a history of coronary heart disease (CHD) at the time of a first acute coronary syndrome (ACS) and to evaluate the relationship of CG symptoms and ACS. METHOD: Overall, 149 subjects with ACS (namely, acute myocardial infarct with or without ST-segment elevation or unstable angina), with no previous history of CHD, admitted to three cardiac intensive care units were included and evaluated by the Structured Clinical Interview for Complicated Grief (SCI-CG), Hamilton Depression Rating Scale, Hamilton Anxiety Rating Scale, and the 36-item Short-Form Health Survey (MOS-SF-36). RESULTS: Of the total sample of 149 subjects with ACS, 118 (79.2%) met criteria for DSM-5 persistent complex bereavement disorder. Among these, subjects who lost a partner, child, or sibling were older (P=0.008), less likely to be working (P=0.032), and more likely to be suffering from hypertension (P=0.021), returned higher scores on the SCI-CG (P=0.001) and developed the index ACS more frequently between 12 and 48 months after the death than those who lost a parent or another relative (P≤0.0001). The occurrence of ACS 12-48 months (P=0.019) after the loss was positively correlated with SCI-CG scores. An inverse relationship with SCI-CG scores was observed for patients who experienced ACS more than 48 months after the loss (P=0.005). The SCI-CG scores significantly predicted lower scores on the "general health" domain of MOS-SF-36 (P=0.030), as well as lower scores on "emotional well-being" domain (P=0.010). CONCLUSION: A great proportion of subjects with ACS report the loss of a loved one. Among these, the loss of a close relative and the severity of CG symptoms are associated with poorer health status. Our data corroborate previous data indicating a strong relationship between CG symptoms and severe cardiac problems.

Influence of depression and anxiety on circulating endothelial progenitor cells in patients with acute coronary syndromes.

OBJECTIVES: Circulating endothelial progenitor cells (EPCs) are related to endothelial function and progression of coronary artery disease. There is evidence of decreased numbers of circulating EPCs in patients with a current episode of major depression. We investigated the relationships between the level of circulating EPCs and depression and anxiety in patients with acute coronary syndrome (ACS). METHODS: Patients with ACS admitted to three Cardiology Intensive Care Units were evaluated by the SCID-I to determine the presence of lifetime and/or current mood and anxiety disorders according to DSM-IV criteria. The EPCs were defined as CD133(+) CD34(+) KDR(+) and evaluated by flow cytometry. All patients underwent standardized cardiological and psychopathological evaluations. Parametric and nonparametric statistical tests were performed where appropriate. RESULTS: Out of 111 ACS patients, 57 were found to have a DSM-IV lifetime or current mood or anxiety disorder at the time of the inclusion in the study. The ACS group with mood or anxiety disorders showed a significant decrease in circulating EPC number compared with ACS patients without affective disorders. In addition, EPC levels correlated negatively with severity of depression and anxiety at index ACS episode. CONCLUSIONS: The current study indicates that EPCs circulate in decreased numbers in ACS patients with depression or anxiety and, therefore, contribute to explore new perspectives in the pathophysiology of the association between cardiovascular disorders and affective disorders.

Noninvasive Transcutaneous Monitoring in Long-Term Follow-Up of Patients With Thromboangiitis Obliterans Treated With Intravenous Iloprost.

We evaluated the effectiveness of intravenous iloprost (IVI) in outpatients with thromboangiitis obliterans (TAO) and lower limb noninvasive transcutaneous monitoring (TCM) at follow-up (FU). Ten consecutive patients with TAO underwent IVI therapy. Transcutaneous oxygen (TcPo 2) and carbon dioxide (TcPco 2) determination and laser Doppler flowmetry (LDF) were performed before and after IVI at 3, 6, and 12 months of FU. Clinical response was positive in 7 patients, whereas 3 nonresponders underwent a second IVI cycle with 1 showing a late positive clinical response. After 12 months of FU, all patients were alive without amputations. Supine and dependent TcP2 levels significantly improved (P < .005). Hallux LDF values showed significant change with the maximal hyperemic test at 44°C (P < .005). Forefoot maximal hyperemic test at 44°C LDF (P < .005) and improved venous arterial reflex (P < .05) showed statistically significant time evolution. We demonstrated some degree of IVI effectiveness and evaluated TCM in patients with TAO.

Distal embolisation during carotid stenting is predicted by circulating levels of LDL cholesterol and C-reactive protein.

AIMS: Distal embolisation during carotid artery stenting (CAS) is the main cause of cerebral complications; thus, the amount of embolisation occurring during CAS can be considered as a surrogate endpoint of cerebral complications. Our aim was to find patient characteristics which are associated with a higher risk of embolisation during CAS. METHODS AND RESULTS: From January to December 2010 all consecutive patients undergoing CAS with embolic protection at three medium- to high-volume Italian centres were prospectively enrolled in this multicentre study. After CAS, the embolic debris was classified by visual inspection into two groups: "scarce" (no debris or hardly visible debris), and "relevant" (visible embolic debris) embolisation. Two hundred and thirty-six consecutive patients (79% males, 32.7% symptomatic) were enrolled. Open cell stents were used in 52.7% of the patients, distal filters were employed in 85.5% and proximal protection in 14.5%. Procedural success was achieved in 100% of procedures. Relevant embolisation was observed in 16.1% of patients, including those who suffered all the periprocedural complications (4.2%). At multivariate statistical analysis, high circulating LDL cholesterol and C-reactive protein levels were the only factors associated with relevant embolisation. CONCLUSIONS: In this study, high circulating LDL cholesterol and C-reactive protein levels were associated with relevant embolisation after CAS, opening up the hypothesis that therapy with statins before elective CAS may reduce plaque embolisation and improve outcome. (EudraCT number: 016737-95).

Design of the rosuvastatin pretreatment to reduce embolization during Carotid Artery Stenting trial.

BACKGROUND: Carotid artery stenting (CAS) is a worldwide diffuse intervention, but may be associated with distal plaque component embolization, and sometimes major and minor stroke. Statin use has been demonstrated to reduce atherosclerotic plaque burden, but its effect in reducing distal embolization during carotid stenting has not yet been well validated. AIMS: With the Rosuvastatin Pretreatment to Reduce Embolization during Carotid Artery Stenting trial, we aim to discover if a pretreatement with high doses of rosuvastatin in dyslipidemic patients is able to reduce periprocedural cerebral ischemic complications following carotid stenting. METHODS: This is a phase III prospective, randomized controlled trial. All consecutive patients with asymptomatic carotid stenosis at least 80% will be randomized to a 6-week rosuvastatin treatment followed by carotid stenting, and to direct carotid stenting. Carotid stenting will be performed following common practice with distal or proximal embolic protection. The primary efficacy end point of the trial will be the prevalence of 'relevant' embolization during CAS, as a surrogate end point for cerebral ischemic complications. Other laboratory and clinical data will be registered and patients will be followed up to 1 year. In order to obtain the expected superiority of statin pretreatment on primary end point, a population of 130 patients will be enrolled into the study. CONCLUSION: In conclusion, with the Rosuvastatin Pretreatment to Reduce Embolization during Carotid Artery Stenting trial, we want to evaluate whether a high dose of rosuvastatin for 6 weeks before CAS in asymptomatic patients with severe carotid stenosis is able to reduce the rate of plaque embolization during the procedure, thus suggesting a possible reduction in cerebral ischemic complications.

Impact of depression on circulating endothelial progenitor cells in patients with acute coronary syndromes: a pilot study.

AIMS: Depression has been identified as a risk factor for an adverse prognosis and reduced survival in patients with acute coronary syndrome (ACS). The number of endothelial progenitor cells (EPCs) is an independent predictor of clinical outcomes in patients with ACS. The aim of this study was to evaluate the impact of depression on EPC levels in patients with ACS. METHODS: Out of 74 ACS patients [23 non-ST-segment elevation myocardial infarction (NSTEMI), 48 STEMI], 36 had a diagnosis of major depressive episode (MDE) according to the Diagnostic and Statistical Manual of Mental Disorders 4th edition (DSM-IV) criteria at the time of the inclusion in the study. Control groups were as follows: 15 healthy individuals and 18 patients with current MDE without a history of cardiovascular diseases. EPCs were defined as CD34CD133KDR and evaluated by flow cytometry. All patients underwent standardized cardiological and psychopathological evaluations. Parametric and nonparametric statistical tests were performed wherever appropriate. RESULTS: ACS patients with MDE showed a significant decrease in circulating EPC number compared with ACS patients without MDE (P < 0.001). The ACS study population was then subdivided into STEMI and NSTEMI groups, and within each group patients with MDE again showed a significant decrease in circulating CD34CD133KDR EPCs compared with others (P <0.001). CONCLUSION: We showed that ACS patients with MDE have a reduced number of circulating CD34CD133KDR cells compared with ACS patients without MDE, suggesting that the presence of MDE reduces the response of bone marrow to acute ischemic events. Considering the reparative role of EPCs in ACS patients, we propose that patients with MDE might be protected less than patients without MDE.

Task force on: 'Early markers of atherosclerosis: influence of age and sex'.

Atherosclerosis and its complications are the most important causes of death all over the world, especially in Western countries. Diet habits, modern stress life, smoking, sedentary way of life and an involvement of genetic pattern of individuals lead to a sure degeneration of quality of life increasing the risk of atherosclerosis development. For this reason, the main purpose of actual medicine is to identify all the markers that could allow the physicians to evaluate the first moments of the development of this dangerous pathological process. The aim is to reduce the speed of its evolution, trying to delay indefinitely the risk coming from the morphological alterations of the vessels. 'Endothelium function' could allow physicians to detect the first moment of the natural history of atherosclerosis process. Its impairment is the first step in the degeneration of vascular structures. Many methods [flow-mediated vasodilatation (FMD); antero-posterior abdominal aorta diameter (APAO); intima-media thickness of the common carotid artery (CCA-IMT); arterial stiffness; and so on] try to evaluate its function, but many limitations come from general population characteristics. A standardization of the methods should take into account individuals' peculiarities. Two elements, not modifiable, should be taken into account for vascular evaluation: age and sex. The aim of this review is to outline the linkage among age, sex and instrumental evaluation of patients considered for a noninvasive assessment of their cardiovascular risk profile.

Delivery of natural polyphenols by polymeric nanoparticles improves the resistance of endothelial progenitor cells to oxidative stress.

PURPOSE: Bone marrow-derived endothelial progenitor cells (EPCs) circulate into peripheral blood and significantly contribute to neo-vascularisation and re-endothelialisation as part of the process of vascular repair. Several studies have reported decreased EPC number in the presence of oxidative stress. Aim of this study was to evaluate the validity of mucoadhesive polymeric nanoparticles as a delivery system of natural products able to protect EPCs from oxidative stress. METHODS: The total polyphenol content and antioxidant capacity of red grape seed extract (GSE) either pre-veraison (p-GSE) or ripe (r-GSE) were measured. Cell viability was evaluated by WST-1 assay. Nanoparticles were prepared by ionotropic crosslinking of two structurally different thiolated quaternary ammonium-chitosan conjugates. A hyaluronic acid solution, containing p-GSE or r-GSE, was added to a stirred solution of each of the two chitosan derivatives to obtain p- or r-GSE loaded nanoparticles (NP) of two types. RESULTS: Both GSE types demonstrated strong antioxidant capacity. p-GSE showed a higher content in total polyphenols compared to r-GSE. NP size was in the 310-340 nm range, with 24 h stability, and nearly 100% encapsulation efficiency for both GSE types. NP were internalized by cells to an extent related directly with their surface charge intensity. GSE-NP uptake significantly improved cell viability and resistance to oxidation. CONCLUSIONS: Nanotechnology has a great potential in nutraceutical delivery. The present results suggest that NP is a highly promising polyphenol carrier system particularly useful to protect EPCs from oxidative stress, thus improving their survival.

Endothelial progenitor cells, cardiovascular risk factors and lifestyle modifications.

Endothelial progenitor cells (EPCs) contribute substantially to preservation of a structurally and functionally intact endothelium. EPCs home in to the sites of endothelial injury and ischemia, where they proliferate, differentiate and integrate into the endothelial layer or exert a paracrine function by producing vascular growth factors. This review will focus on successful lifestyle interventions that aim to maintain vascular health through beneficial actions on cell populations with vasculogenic potential. The results of the studies proving the role of healthy lifestyle are particularly emphasized.

Effect of aging on metabolic pathways in endothelial progenitor cells.

Age represents a significant risk factor for the onset and progression of cardiovascular disease, with the increase in life expectancy in developed countries going in parallel with increased incidence of such pathologies. Treatment strategies alternative or additive to pharmacological treatments are needed. The relationship between aging and progenitor cell-mediated repair is of great interest. Endothelial progenitor cells (EPC) mediate repair mechanisms for endothelial regeneration and maintenance, but they are subject to age-associated changes affecting negatively their number and/or function. Aim of this review is to examine the impact of age on EPC-mediated vascular repair, with a focus on the metabolic pathways involved and on the therapeutic targets with potential for attenuating this effect.

Lack of a relationship between circulating gamma-glutamyltransferase levels and carotid intima media thickness in hypertensive and diabetic patients.

BACKGROUND: By increasing the intracellular prooxidant burden, gamma-glutamyltransferase (GGT) may accelerate atherosclerotic vascular disease. That noxious influence may be reflected by circulating enzyme levels, a correlate of cardiovascular risk factors, and a predictor of incident events. To evaluate this hypothesis, we tested the association between circulating GGT and common carotid intima-media thickness (CIMT), a surrogate index of systemic atherosclerotic involvement, in a large and well-characterized group of patients at risk of cardiovascular disease (CVD). PATIENTS: This study analyzed 548 patients with hypertension and/or diabetes and a widely prevalent history of CVD. Subjects with known hepatic disease and abnormal GGT values were excluded. METHODS: CIMT (B-mode ultrasonography) values were the mean of four far-wall measurements at both common carotids. Metabolic syndrome (MetS) was diagnosed according to National Cholesterol Education Program-Adult Treatment Panel III criteria. Due to inherent sex-related differences in GGT levels, the data were analyzed separately in males and females in samples dichotomized by the median. RESULTS: The age-adjusted CIMT values did not differ by GGT levels in males or females. In contrast, the carotid wall was consistently thicker in patients with a history of CVD and MetS independent of age and concurrent GGT values. In both sexes, GGT was associated with key components of the MetS such as triglycerides, fasting plasma glucose, and body mass index. CONCLUSION: The data collected in this mixed group of hypertensive and/or diabetic patients with widely prevalent history of CVD do not support the concept of a direct pathophysiological link between GGT levels within reference limits and atherosclerotic involvement.

Differential effects of fondaparinux and bemiparin on angiogenic and vasculogenesis-like processes.

INTRODUCTION: Conventional therapy for venous thromboembolism or acute coronary syndrome involves the administration of glycoanticoagulants (heparins) or oligosaccharides (fondaparinux). We evaluated the effects of such drugs on angiogenesis and vasculogenesis-like models. MATERIALS AND METHODS: Human umbilical vein endothelial cells or human endothelial progenitor cells were treated with bemiparin, fondaparinux or unfractionated heparin, at concentrations reflecting the doses used in clinical practice. After 24h, cell viability, proliferation, tubule formation and angiogenic molecular mechanisms, such as activation of the serine/threonine kinase AKT, were assessed. In vivo angiogenesis was studied using a Matrigel sponge assay in mice. RESULTS: Bemiparin gave a significant decrease of in vitro angiogenesis as shown by the reduction of endothelial cell tubule network, while both fondaparinux and unfractionated heparin did not show any significant effect. In assays of Matrigel sponge invasion in mice, unfractionated heparin was able to stimulate angiogenesis and, conversely, bemiparin inhibited angiogenesis. Furthermore, both bemiparin and fondaparinux caused a significant reduction in an in vitro vasculogenesis-like model, as demonstrated by the decrease of tubule network after co-seeding of endothelial progenitor cells and human umbilical vein endothelial cells. In addition, unfractionated heparin but not bemiparin was able to increase AKT phosphorylation. CONCLUSIONS: In in vitro experiments, bemiparin was the only drug to show an anti-angiogenic and vasculogenic-like effect, unfractionated heparin showed only a trend to increase in angiogenesis assay and fondaparinux affected only the vasculogenesis-like model. Notably, the in vivo experiments corroborated these data. Such results are important for the choice of a patient-tailored therapy.

Red grape skin and seeds polyphenols: Evidence of their protective effects on endothelial progenitor cells and improvement of their intestinal absorption.

SCOPE: To evaluate the ability of grape skin and seeds to protect endothelial progenitor cells (EPC) from oxidative stress induced by hyperglycemia (HG) compared to red wine (RW) and prepare innovative pharmaceutical systems for the oral administration of red grape extract allowing the overcoming of its poor intestinal absorption. METHODS AND RESULTS: Human EPC were characterized by expression of cell surface markers. Cells were incubated with different concentrations of total polyphenols from grape components or RW in the presence or absence of HG. Cell viability, migration, adhesion, and reactive oxygen species (ROS) production were assayed. Intestinal permeation of polyphenols was studied in the absence or presence of a quaternary ammonium-chitosan conjugate (N⁺(60)-Ch). Grape components and RW increased EPC viability, adhesion and migration, and prevented the HG effect (P < 0.01). ROS production induced by HG was significantly reduced only by grape seed extract and RW (P < 0.01). N⁺(60)-Ch acted as an effective enhancer of polyphenol permeability across the excised rat intestine. CONCLUSIONS: Red grape components are a source of antioxidant compounds that ameliorate EPC viability and function, while preventing endothelial dysfunction. The use of polycationic chitosan derivatives can promote the absorption of polyphenols across intestinal epithelium, thus increasing their bioavailability and potential therapeutic value in atherosclerosis.

Myocardial delayed enhancement in paucisymptomatic nonischemic dilated cardiomyopathy.

OBJECTIVES: We investigated the prognostic role of myocardial fibrosis by delayed enhancement (DE) cardiovascular magnetic resonance (CMR) in nonischemic dilated cardiomyopathy (NICM) patients with no or mild symptoms of heart failure (HF). METHODS: A prospective cohort of 125 NICM patients (82 males, age 59±14years, mean±SD) with echocardiographic evidence of left ventricular (LV) systolic dysfunction (mean ejection-fraction 33±10%), without (stage B) or with history of mild HF symptoms (stage C, NYHA classes I-II) was enrolled. The end-point was a composite of cardiac death and HF hospitalization. RESULTS: Fifty (40%) patients showed myocardial DE, representing 12±7% of LV mass. During a median follow-up of 14.2months, 16 (32%) patients with DE experienced a composite event versus only 6 (8%) patients without DE (Kaplan-Meier survival curve, p=0.001). After correction for age, CMR-derived LV and right ventricular volumes, echocardiographic measurements of LV diastolic function and Doppler-estimated systolic pulmonary artery pressure, the presence of DE remained a strong and independent predictor of cardiac death or HF hospitalization (hazard ratio: 5.32, 95% confidence intervals 1.60 to 17.63, p=0.006). CONCLUSIONS: In NICM patients with no or mild HF symptoms, the presence of myocardial DE is a strong predictor of worse clinical outcome even after correction for other established prognostic determinants. Contrast-enhanced CMR may be useful in prognostic stratification from the early stages of NICM.

Coronary artery anomalies and their clinical relevance.

Coronary artery anomalies (CAAs) represent one of the most confusing topic in cardiology and affect approximately 1% of the general population. Although some anomalies seem to be only anatomical curiosities, others may sometimes have fatal consequences. This review describes the anatomical characteristics of main CAAs and focuses on the pathophysiological mechanisms by which CAAs may cause a pathological state. The last section describes these therapeutical options of this congenital disorders.

Circulating endothelial progenitor cells and large artery structure and function in young subjects with uncomplicated type 1 diabetes.

BACKGROUND: Carotid intima-media thickness (IMT), indices of large artery stiffness and measures of endothelium function may be used as markers of early atherosclerosis in type 1 diabetes mellitus (T1DM). The aim of the present study was to compare the indices of large artery structure and function as well as endothelial function and regenerating capacity between adolescents with T1DM and healthy control of similar age. In addition, the associations of different vascular measures with endothelial progenitor cells (EPCs), glyco-metabolic control and serum levels of advanced glycation endproducts (AGEs), soluble receptors for AGEs (sRAGE) and adiponectin were evaluated. METHODS: Sixteen uncomplicated young T1DM patients (mean age 18 ± 2 years, history of disease 11 ± 5 years, HbA1c 7.7 ± 1.1%) and 26 controls (mean age 19 ± 2 years) were studied. A radiofrequency-based ultrasound system (Esaote MyLab 70) was used to measure carotid IMT and wave speed (WS, index of local stiffness), applanation tonometry (PulsePen) was applied to obtain central pulse pressure (PP) and augmentation index (AIx), and carotid-femoral pulse wave velocity (PWV, Complior) was used as index of aortic stiffness. Peripheral endothelium-dependent vasodilation was determined as reactive hyperemia index (RHI, EndoPAT). Circulating EPCs, glycometabolic profile, AGEs (autofluorescence method), sRAGE and adiponectin were also measured. RESULTS: After adjusting for age, sex and blood pressure, T1DM adolescents had significantly higher carotid IMT (456 ± 7 vs. 395 ± 63 µm, p < 0.005), carotid WS (p < 0.005), PWV (p = 0.01), AIx (p < 0.0001) and central PP (p < 0.01) and lower EPCs (p = 0.02) as compared to controls. RHI was reduced only in diabetic patients with HbA1c ≥7.5% (p < 0.05). In the overall population, EPCs were an independent determinant of carotid IMT (together with adiponectin), while fasting plasma glucose was an independent determinant of carotid WS, AIx and central PP. CONCLUSIONS: Our findings suggest that young subjects with relatively long-lasting T1DM have a generalized preclinical involvement of large artery structure and function, as well as a blunted endothelium regenerating capacity. Hyperglycemia and suboptimal chronic glycemic control seem to deteriorate the functional arterial characteristics, such as large arteries stiffness, wave reflection and peripheral endothelium-dependent vasodilation, whereas an impaired endothelium regenerating capacity and adiponectin levels seem to influence arterial structure.