Circulating Endothelial Progenitor Cells Levels Research Articles

The Effect of SGLT2 Inhibitor Therapy on Endothelial Progenitor Cell Function in Patients with Heart Failure.

Sodium-glucose cotransporter-2 (SGLT-2) inhibitors have been shown to reduce the risk of cardiovascular mortality and hospitalizations in patients with heart failure (HF) with preserved or reduced ejection fraction (HFpEF or HFrEF). The mechanism for this benefit is not clear. Endothelial progenitor cells (EPCs) are bone-marrow derived cells able to differentiate into functional endothelial cells and participate in endothelial repair. The aim of the current study was to evaluate the effect of SGLT-2 inhibitors on the level and function of EPCs in patients with HF. We enrolled 20 patients with symptomatic HF, 12 with HFrEF and 8 with HFpEF (aged 73.3±10.2 years, 95% men). Blood samples were drawn at 2 time points: baseline and ≥3 months after initiation of SGLT-2 inhibitor therapy. Circulating EPC levels were evaluated by expression of VEGFR-2, CD34 and CD133 by flow-cytometry. EPCs colony forming units (CFUs) were quantified after 7 days in culture. The proportion of cells that co-expressed VEGFR-2 and CD34 or VEGFR-2 and CD133 was higher following 3 months of SGLT-2 inhibitors [0.26% (IQR 0.10-0.33) vs. 0.55% (IQR 0.28-0.91), P=0.002; 0.12% (IQR 0.07-0.15) vs. 0.24% (IQR 0.15-0.39), P=0.001, respectively]. EPCs-CFU were also increased following SGLT-2 inhibitor treatment [23 (IQR 3.7-37.8) vs. 79.4 (IQR 25.1-110.25) colonies/106 cells, P=0.0039]. In patients with symptomatic HF, both HFpEF and HFrEF, treatment with SGLT-2 inhibitors is associated with an increase in circulating EPCs level and function. This augmentation in EPCs may be a contributing mechanism to the clinical benefit of SGLT-2 inhibitors in HF patients.

TRIM27 Promotes Endothelial Progenitor Cell Apoptosis in Patients with In-Stent Restenosis by Ubiquitinating TBK1.

Approximately 2-10% in-stent restenosis (ISR) may occur following percutaneous coronary intervention (PCI) despite the use of modern drug-eluting stents (DES); thus, our study aimed to explore the effects of tripartite motif-containing (TRIM) 27 on ISR and the underlying mechanism. For this purpose, a total of 42 patients undergoing coronary angiography who had prior coronary angiography with DES implantation were recruited. Endothelial progenitor cells (EPCs) markers (defined as CD34 and vascular endothelial growth factoreceptor-2 (VEGFR-2)) in peripheral blood were measured to asses the circulating EPC level. The TRIM family-related gene expressions were detected by reverse transcription-quantitative polymerase chain reaction. Results suggested that ISR patients had reduced CD34+VEGFR-2+ and increased apoptosis rate of EPCs, along with upregulated TRIM27 and TRIM37 and downregulated TRIM28. TRIM27 promoted and TBK1 inhibited the apoptosis rate of EPCs. Mechanically, TRIM27 interacted with TBK1 to ubiquitinate TBK1 in in vitro study. In summary, TRIM27 promoted the progression of ISR in patients after PCI by ubiquitinating TBK1, which might provide novel ideas for the clinical treatment of ISR.

Could endothelial progenitor cells complement the diagnosis of inflammatory arthritis? A systematic review and meta-analysis.

The objective of this meta-analysis was to systematically review existing evidence and evaluate variations in levels of circulating endothelial progenitor cells (EPCs) among individuals with psoriatic arthritis (PsA), juvenile idiopathic arthritis (JIA), and rheumatoid arthritis (RA). Relevant studies were identified through database searches, and 20 records were enrolled. We used the fixed-effect model or random-effect model to estimate the pooled standardized mean difference (SMD) with 95% confidence intervals (CIs) in circulating EPC levels between inflammatory arthritis patients and controls. The results showed that circulating EPC levels differed among subtypes of inflammatory arthritis, with significantly lower levels in patients with RA (SMD = -0.848, 95% CI = -1.474 to -0.221, p = 0.008) and PsA (SMD = -0.791, 95% CI = -1.136 to -0.446, p < 0.001). However, no statistically significant difference was found in circulating EPC levels between patients with JIA and controls (SMD = -1.160, 95% CI = -2.578 to 0.259, p = 0.109). Subgroup analyses suggested that in patients with RA, circulating EPC levels were influenced by age, disease activity, and duration. Although many studies have investigated circulating EPC levels in patients with inflammatory arthritis, the results have been inconsistent. This meta-analysis offers a comprehensive overview of the existing evidence and emphasizes the association between levels of circulating EPCs and various types of arthritis. However, further research is needed to determine the specific mechanisms underlying the observed differences in EPC levels in different types of arthritis and to establish the clinical utility of this biomarker.

Endothelial progenitor cells and major adverse cardiovascular events in patients receiving elective coronary angiography

Background and purpose: The association of circulating endothelial progenitor cells (EPCs) with different cardiovascular diseases and their related major adverse cardiovascular events (MACE) remained inconclusive. We aimed to clarify associations between the circulating EPC levels and the risk of MACE concerning different atherosclerosis-related diseases. Methods: This prospective cohort study was conducted from December 2009 to March 2015. Patients who underwent non-emergent coronary angiography (CAG) were included. The circulating EPC levels were measured using flow cytometry prior to the CAG procedure. The study evaluation of circulating EPC levels among patients with obstructive coronary artery disease (CAD) and other comorbidities. Patients were then assigned to tertiles by circulating EPC levels to evaluate the predictive values of the development of MACEs. Results: The study enrolled 1099 patients, of whom, 736 (67%) were men, with a mean age of 66.7 ± 12.5 years old. Overall, 637 (58%) patients were diagnosed with obstructive CAD according to CAG. MACE occurred in 268 (24.4%) patients. Circulating EPC levels were lower in patients with peripheral artery disease (PAD) but not associated with the presence of obstructive CAD, atrial fibrillation, chronic kidney disease (CKD), heart failure, and diabetes mellitus. Higher circulating EPC levels are linked with higher MACE among patients with suspected CAD, regardless of the presence or absence of obstructive CAD or CKD. The association did not present in patients with PAD. Conclusions: Higher circulating EPC levels are associated with a greater risk of MACE, regardless of the presence of obstructive CAD or CKD. This association was not apparent in the patients with PAD, suggesting impaired endothelial repair in these patients.

Identification of protective biologic factors in patients with high cardiovascular risk, but normal coronary arteries (NormCorn).

Endothelial progenitor cells (EPCs) have an important role in repair following vascular injury. Telomere length has been shown to be correlated with genome stability and overall cell health. We hypothesized that both EPCs and telomere size are related to protective mechanisms against coronary artery disease. Our aim was to evaluate the level and function of circulating EPCs and telomere length in patients with multiple cardiovascular risk factors and anatomically normal coronary arteries vs. matched controls. We included 24 patients, with coronary CTA demonstrating normal coronaries and a high risk of CAD of >10% by ASCVD risk estimator. Control groups included 17 patients with similar cardiovascular profiles but with established CAD and a group of 20 healthy volunteers. Circulating EPCs levels were assessed by flow cytometry for expression of vascular endothelial growth factor receptor 2, CD34 and CD133. The capacity of the cells to form colony forming units (CFUs) was quantified after 1 week of culture. Telomere length was determined by the southern blotting technique. Patients with high risk for CVD and normal coronaries had augmented EPCs function, compared with the CAD group (1.1 vs. 0.22 CFU/f; P = 0.04) and longer telomeres compared with the CAD group (10.7 kb vs. 2.8 kb P = 0.015). These patients displayed a similar profile to the healthy group. Patients with a high risk for CAD, but normal coronary arteries have EPCs function and telomere length which resemble healthy volunteers, and augmented compared with patients with established CAD, which could serve as a protective mechanism against atherosclerosis development in these high-risk patients.

N‑acetyl cysteine prevents ambient fine particulate matter‑potentiated atherosclerosis via inhibition of reactive oxygen species‑induced oxidized low density lipoprotein elevation and decreased circulating endothelial progenitor cell.

Ambient fine particulate matter (PM) serves an important role in the development of cardiovascular disease, including atherosclerosis. Antioxidant N-acetyl cysteine (NAC) has protective effects in the cardiovascular system. However, it is unknown if NAC prevents PM-potentiated atherosclerosis in hyperlipidemia. Low-density lipoprotein (LDL) receptor knockout mice were pretreated with 1 mg/ml NAC in drinking water for 1 week and continued to receive NAC, high-fat diet and intranasal instillation of PM for 1 week or 6 months. Blood plasma was collected for lipid profile, oxidized (ox-)LDL, blood reactive oxygen species (ROS) and inflammatory cytokine (TNF-α, IL-1β and IL-6) measurement. Blood cells were harvested for endothelial progenitor cell (EPC) population and intracellular ROS analysis. Murine aorta was isolated for atherosclerotic plaque ratio calculation. NAC treatment maintained circulating EPC level and significantly decreased blood ox-LDL and ROS, inflammatory cytokines, mononuclear and EPC intracellular ROS levels as well as aortic plaque ratio. NAC prevented PM-potentiated atherosclerosis by inhibiting plasma ROS-induced ox-LDL elevation, mononuclear cell and EPC intracellular ROS-induced circulating EPC reduction and inflammatory cytokine production.

Far-Infrared Therapy Decreases Orthotopic Allograft Transplantation Vasculopathy.

Orthotopic allograft transplantation (OAT) is a major strategy for solid heart and kidney failure. However, the recipient’s immunity-induced chronic rejection induces OAT vasculopathy that results in donor organ failure. With the exception of immunosuppressive agents, there are currently no specific means to inhibit the occurrence of OAT vasculopathy. On the other hand, far-infrared (FIR) therapy uses low-power electromagnetic waves given by FIR, with a wavelength of 3–25 μm, to improve human physiological functions. Previous studies have shown that FIR therapy can effectively inhibit inflammation. It has also been widely used in adjuvant therapy for various clinical diseases, especially cardiovascular diseases, in recent years. Thus, we used this study to explore the feasibility of FIR in preventing OAT vasculopathy. In this study, the model of transplantation of an aorta graft from PVG/Seac rat to ACI/NKyo rat, and in vitro model of human endothelial progenitor cells (EPCs) was used. In this report, we presented that FIR therapy decreased the serious of vasculopathy in OAT-recipient ACI/NKyo rats via inhibiting proliferation of smooth muscle cells, accumulation of collagen, and infiltration of fibroblast in the vessel wall; humoral and cell-mediated immune responses were decreased in the spleen. The production of inflammatory proteins/cytokines also decreased in the plasma. Additionally, FIR therapy presented higher mobilization and circulating EPC levels associated with vessel repair in OAT-recipient ACI/NKyo rats. In vitro studies demonstrated that the underlying mechanisms of FIR therapy inhibiting OAT vasculopathy may be associated with the inhibition of the Smad2-Slug axis endothelial mesenchymal transition (EndoMT). Thus, FIR therapy may be the strategy to prevent chronic rejection-induced vasculopathy.

Endothelial Progenitor Cell Levels and Extent of Post-prandial Lipemic Response.

Background and ObjectiveDue to the frequency of meal ingestion, individuals spend the majority of the day, ~18 h, in a status of post-prandial (PP) stress. Remnant-like lipoprotein particles (RLPs) are predominant in PP phase playing an important role in the development of atherosclerosis. Endothelial progenitor cells (EPCs) have been suggested to play a role in vessel wall homeostasis and in reducing atherosclerosis. However, there is no information about peripheral blood EPCs number following PP stress. We investigated the association between circulating EPCs levels and extent of PP lipemia in healthy subjects following a high-fat meal.Materials and MethodsA total of 84 healthy subjects (42 men, 42 women) aged 17–55 years were included in the study. PP lipemic response of subjects was determined by Oral Fat-Loading Test (OFLT). All the subjects were classified on the basis of their plasma TG levels after PP lipemic stressors in categories 1 (low), 2 (moderate), and 3 (high). Circulating EPCs numbers were measured by the flow cytometry method.ResultsThere was a significant difference in terms of lipid parameters between men and women: high-density lipoprotein cholesterol (HDL-C) was significantly lower in men than in women (p < 0.001). Total cholesterol (TC) (p = 0.004), low-density lipoprotein cholesterol (LDL-C) (p < 0.001), triglyceride (TG) (p < 0.001), and TG-AUC (p < 0.001) were significantly higher in men than in women. There was no significant difference between the genders in terms of CD34+KDR+ and CD34+KDR+CD133+cell number and MMP-9 levels. Vascular endothelial growth factor (VEGF) levels were significantly higher in men than women (p = 0.004). TC, LDL-C, and TG were significantly higher in the 3rd category than 1st and 2nd categories (p < 0.001) in women. Age, body mass index (BMI), fat rate, TG, TC, and LDL-C were significantly higher in the 3rd category than 1st category (p < 0.001, p = 0.002, p = 0.002, p = 0.01, p = 0.007, p = 0.004; respectively), in men. Circulating numbers of EPCs in men were significantly higher in the PP hyperlipidemia group than in the low TG levels category, independently from age (p < 0.05). Circulating EPC levels showed a positive correlation with OFLT response in men (r = 0.414, p < 0.05). Also, OFLT response showed a strong positive correlation with fasting TG levels (r = 0.930, p < 0.001). EPC levels in categories of women were not different.ConclusionIncreased EPCs levels in subjects with different PP hyperlipidemia may be associated with a response to endothelial injury, related to increased atherogenic remnant particles at the PP phase.

Prognostic, diagnostic and therapeutic potential of endothelial progenitor cells for patients with ischaemic stroke: Hype or Hope

Ischaemic stroke is a debilitating disease with immense personal, societal and economic impact. Thrombolysis with recombinant tissue plasminogen activator remains the only approved pharmacotherapy for this disease. As each year less than 1% of eligible patients receive this therapy worldwide, efficacious new therapeutics are desperately needed. Emerging evidence suggest endothelial progenitor cells (EPCs), capable of repairing damaged vasculature, as one such therapeutics. However, questions regarding their optimal dose, delivery route and in vivo survivability remain largely unanswered. Outgrowth endothelial cells, generated in large numbers by ex vivo expansion of EPCs, enable effective assessment of these issues and may eventually serve as off-the-shelf therapeutics. Correlations between circulating EPC levels and stroke outcome imply that EPCs may also serve as clinical biomarkers for stroke. This viewpoint briefly evaluates the current evidence, pinpoints the gaps in the literature and proposes new directions for research.

Increased Levels of Circulating Angiogenic Cells and Signaling Proteins in Older Adults With Cerebral Small Vessel Disease.

Background: Cerebral small vessel disease (SVD) is associated with increased risk of stroke and dementia. Progressive damage to the cerebral microvasculature may also trigger angiogenic processes to promote vessel repair. Elevated levels of circulating endothelial progenitor cells (EPCs) and pro-angiogenic signaling proteins are observed in response to vascular injury. We aimed to examine circulating levels of EPCs and proangiogenic proteins in older adults with evidence of SVD.Methods: Older adults (ages 55–90) free of dementia or stroke underwent venipuncture and brain magnetic resonance imaging (MRI). Flow cytometry quantified circulating EPCs as the number of cells in the lymphocyte gate positively expressing EPC surface markers (CD34+CD133+CD309+). Plasma was assayed for proangiogenic factors (VEGF-A, VEGF-C, VEGF-D, Tie-2, and Flt-1). Total SVD burden score was determined based on MRI markers, including white matter hyperintensities, cerebral microbleeds and lacunes.Results: Sixty-four older adults were included. Linear regression revealed that older adults with higher circulating EPC levels exhibited greater total SVD burden [β = 1.0 × 105, 95% CI (0.2, 1.9), p = 0.019], after accounting for age and sex. Similarly, a positive relationship between circulating VEGF-D and total SVD score was observed, controlling for age and sex [β = 0.001, 95% CI (0.000, 0.001), p = 0.048].Conclusion: These findings suggest that elevated levels of circulating EPCs and VEGF-D correspond with greater cerebral SVD burden in older adults. Additional studies are warranted to determine whether activation of systemic angiogenic growth factors and EPCs represents an early attempt to rescue the vascular endothelium and repair damage in SVD.

Circulating Endothelial Progenitor Cells Are Preserved in Female Mice Exposed to Ambient Fine Particulate Matter Independent of Estrogen.

Males have a higher risk for cardiovascular diseases (CVDs) than females. Ambient fine particulate matter (PM) exposure increases CVD risk with increased reactive oxygen species (ROS) production and oxidative stress. Endothelial progenitor cells (EPCs) are important to vascular structure and function and can contribute to the development of CVDs. The aims of the present study were to determine if sex differences exist in the effect of PM exposure on circulating EPCs in mice and, if so, whether oxidative stress plays a role. Male and female C57BL/6 mice (8–10 weeks old) were exposed to PM or a vehicle control for six weeks. ELISA analysis showed that PM exposure substantially increased the serum levels of IL-6 and IL-1β in both males and females, but the concentrations were significantly higher in males. PM exposure only increased the serum levels of TNF-α in males. Flow cytometry analysis demonstrated that ROS production was significantly increased by PM treatment in males but not in females. Similarly, the level of circulating EPCs (CD34+/CD133+ and Sca-1+/Flk-1+) was significantly decreased by PM treatment in males but not in females. Antioxidants N-acetylcysteine (NAC) effectively prevented PM exposure-induced ROS and inflammatory cytokine production and restored circulating EPC levels in male mice. In sharp contrast, circulating EPC levels remained unchanged in female mice with PM exposure, an effect that was not altered by ovariectomy. In conclusion, PM exposure selectively decreased the circulating EPC population in male mice via increased oxidative stress without a significant impact on circulating EPCs in females independent of estrogen.

Reduced effects of cardiac extracorporeal shock wave therapy on angiogenesis and myocardial function recovery in patients with end-stage coronary artery and renal diseases

BackgroundGrowing evidence have shown cardiac extracorporeal shock wave therapy (ESWT) improve clinical symptoms and left ventricular ejection fraction (LVEF) for patients with end-stage diffuse coronary artery disease (EnD-CAD) unsuitable for coronary interventions. However, little is known whether cardiac ESWT remains effective on symptomatic relief and improvement of LVEF for the EnD-CAD patients with end-stage renal disease (ESRD). MethodsThis was a small-scale prospective study. Between August 2016 and January 2019, a total of 16 subjects received cardiac ESWT for their EnD-CAD. They were divided into two groups according to ESRD or not, i.e., EnD-CAD group (n = 8) and EnD-CAD/ESRD group (n = 8). Clinical symptoms including angina and dyspnea, levels of circulating endothelial progenitor cells (EPC), LVEF, and adverse events were regularly followed up for one year to compare safety and efficacy of cardiac ESWT between the EnD-CAD patients with or without ESRD. ResultsAll participants tolerated cardiac ESWT without any relevant side effects such as skin allergic reaction, local redness/tenderness or cardiac arrhythmia. There were similar baseline comorbidities and clinical features between two groups, but the EnD-CAD/ESRD group had significantly higher serum potassium level as well as lower renal function and lipid profile (all p-values <0.03). After cardiac ESWT, the patients in both groups had significant improvement in angina and dyspnea at 1 year (all p-values <0.03). However, the EnD-CAD/ESRD group did not have increase in either circulating EPC levels or LVEF at 6 months (mean change in LVEF: −4.00% ± 8.32%, p = 1.000). In contrast, the EnD-CAD group had gradually improving levels of circulating EPC surface markers and increased LV systolic function (mean change in LVEF: +4.87% ± 8.76%, p = 0.092). Notably, patients in the EnD-CAD/ESRD group suffered from high incidental clinical adverse events before and after enrollment into the ESWT study (75% vs. 25%, p = 0.132). ConclusionAlthough cardiac ESWT provided improvement of clinical symptoms in the EnD-CAD patients, its long-term effects on the angiogenesis and LVEF were reduced for those high-risk patients with concomitant EnD-CAD and ESRD. Trial registrationnone.

Adjunctive Cilostazol to Dual Antiplatelet Therapy to Enhance Mobilization of Endothelial Progenitor Cell in Patients with Acute Myocardial Infarction: A Randomized, Placebo-Controlled EPISODE Trial

Background: Endothelial progenitor cells (EPCs) have the potential to protect against atherothrombotic event occurrences. There are no data to evaluate the impact of cilostazol on EPC levels in high-risk patients. Methods: We conducted a randomized, double-blind, placebo-controlled trial to assess the effect of adjunctive cilostazol on EPC mobilization and platelet reactivity in patients with acute myocardial infarction (AMI). Before discharge, patients undergoing percutaneous coronary intervention (PCI) were randomly assigned to receive cilostazol SR capsule (200-mg) a day (n = 30) or placebo (n = 30) on top of dual antiplatelet therapy (DAPT) with clopidogrel and aspirin. Before randomization (baseline) and at 30-day follow-up, circulating EPC levels were analyzed using flow cytometry and hemostatic measurements were evaluated by VerifyNow and thromboelastography assays. The primary endpoint was the relative change in EPC levels between baseline and 30-day. Results: At baseline, there were similar levels of EPC counts between treatments, whereas patients with cilostazol showed higher levels of EPC counts compared with placebo after 30 days. Cilostazol versus placebo treatment displayed significantly higher changes in EPC levels between baseline and follow-up (ΔCD133+/KDR+: difference 216%, 95% confidence interval (CI) 44~388%, p = 0.015; ΔCD34+/KDR+: difference 183%, 95% CI 25~342%, p = 0.024). At 30-day follow-up, platelet reactivity was lower in the cilostazol group compared with the placebo group (130 ± 45 versus 169 ± 62 P2Y12 Reaction Unit, p = 0.009). However, there were no significant correlations between the changes of EPC levels and platelet reactivity. Conclusion: Adjunctive cilostazol on top of clopidogrel and aspirin versus DAPT alone is associated with increased EPC mobilization and decreased platelet reactivity in AMI patients, suggesting its pleiotropic effects against atherothrombotic events (NCT04407312).

Improvement in circulating endothelial progenitor cells pool after cardiac resynchronization therapy: increasing the list of benefits

BackgroundRecent studies suggest that circulating endothelial progenitor cells (EPCs) may influence the response to cardiac resynchronization therapy (CRT). The aim of this study was to evaluate the effect of CRT on EPC levels and to assess the impact of EPCs on long-term clinical outcomes.Population and methodsProspective study of 50 patients submitted to CRT. Two populations of circulating EPCs were quantified previously to CRT implantation: CD34+KDR+ and CD133+KDR+ cells. EPC levels were reassessed 6 months after CRT. Endpoints during the long-term follow-up were all-cause mortality, heart transplantation, and hospitalization for heart failure (HF) management.ResultsThe proportion of non-responders to CRT was 42% and tended to be higher in patients with an ischemic vs non-ischemic etiology (64% vs 35%, p = 0.098). Patients with ischemic cardiomyopathy (ICM) showed significantly lower CD34+KDR+ EPC levels when compared to non-ischemic dilated cardiomyopathy patients (DCM) (0.0010 ± 0.0007 vs 0.0030 ± 0.0024 cells/100 leukocytes, p = 0.032). There were no significant differences in baseline EPC levels between survivors and non-survivors nor between patients who were rehospitalized for HF management during follow-up or not. At 6-month follow-up, circulating EPC levels were significantly higher than baseline levels (0.0024 ± 0.0023 vs 0.0047 ± 0.0041 CD34+KDR+ cells/100 leukocytes, p = 0.010 and 0.0007 ± 0.0004 vs 0.0016 vs 0.0013 CD133+/KDR+ cells/100 leukocytes, p = 0.007).ConclusionsPatients with ICM showed significantly lower levels of circulating EPCs when compared to their counterparts. CRT seems to improve the pool of endogenously circulating EPCs and reduced baseline EPC levels seem not to influence long-term outcomes after CRT.Graphical abstract

Alterations in the Levels of Circulating and Endothelial Progenitor Cells Levels in Young Adults with Type 1 Diabetes: A 2-Year Follow-Up from the Observational METRO Study.

PurposeType 1 diabetes is associated with high risk of cardiovascular disease (CVD). Reduced levels of circulating progenitor cells (CPCs) and endothelial progenitor cells (EPCs) have been indicated as a risk factor for adverse cardiovascular outcomes and death in people at high cardiovascular risk. The aim of the present study was to evaluate the change in CPCs and EPCs levels in a population of young type 1 diabetic patients treated with intensive insulin regimen over a period of 2 years.Patients and MethodsA total of 204 type 1 diabetic patients, of whom 84 treated with insulin pump (CSII) and 120 with multiple daily insulin injections (MDI), completed a 2-year follow-up. Clinical measurements, including the indices of glycemic control and glucose variability, were collected at baseline and after 2 years. Both CPC and EPC cell count were assessed by flow cytometry.ResultsMean age of participants was 24.5 years and mean diabetes duration was 13.6 years. After 2 years, we found a significant reduction of HbA1c (−0.3% versus baseline, P <0.001), associated with decrease in mean amplitude of glucose excursion (MAGE) (−0.5 mmol/L versus baseline, P<0.001), continuous overall net glycemic action (CONGA) (−0.2 mmol/L versus baseline, P=0.006), and blood glucose standard deviation (BGSD) (−0.2 mmol/L versus baseline, P<0.001). The number of all EPCs phenotypes, but not CPC cell count, significantly raised up in the entire population, with higher increase in CSII group. MAGE resulted as an independent predictor for increased levels of both CD34+ (P = 0.020) and CD34+KDR+ (P = 0.004) cell count in the whole population.ConclusionOver a 2-year follow-up, young type 1 diabetic patients showed an increase in circulating EPCs levels, which was higher in patients with CSII. Glucose variability resulted as an independent predictor of the raised levels of EPCs in this selected population.

P750Role of circulating endothelial cells post-heart transplantation

Abstract Background The role of endothelial progenitor cells (EPC) in heart transplantation (HT) is not well defined. Thus, the aim of this study was to evaluate prospectively the dynamic changes of circulating EPC levels in relation to post-HT rejection risk. Methods There were 27 HT recipients who had EPC from peripheral blood quantified during 6 months follow-up after HT. Patients were monitored regularly, by right ventricular endomyocardial biopsy assessment, for cellular rejection (ACR) defined as grade ≥2 or an antibody-mediated rejection (AMR) characterized by histopathological changes recorded as AMR1H. The primary end-point was acute rejection, either AMR or ACR. Results ACR and AMR were observed in 7 (25.9%) and 6 (22.2%) subjects respectively. EPC levels, after logarithmic transformation, immediately post-HT were alike regardless of ACR status, however patients with lower EPC were at risk of AMR at 1 month (Table 1). On the other hand patients with a significant reduction of EPC at 1 month post-HT compared with HT were less likely to have either ACR or AMR (p=0.0003). During longer post-HT observation (12 months) patients had similar EPC levels regardless of the rejection events. Dynamic changes in EPC levels are presented in figure. Nonetheless, greater changes in EPC expressed by coefficient of variation were associated with the risk of either AMR or ACR compared to the participants without rejection (mean [lower–upper quartile]) 15 [13–18] vs 8 [5–13]; p=0.02) and (22 [14–26] vs 8 [5–13]; p=0.01) respectively. EPC by rejection – 1st month following HT ACR (+) AMR (+) ACR (−) and AMR (−) p^ p p N=3 (mean± SD) N=4 (mean± SD) N=20 (mean± SD) ACR (+) vs ACR (−) and AMR (−) AMR (+) vs ACR (−) and AMR (−) EPC log HT 5.14±1.55 3.81±1.01 5.30±0.88 0.0325 0.97 0.025 EPC log M1 4.97±0.59 3.69±1.33 4.15±1.29 0.4160 0.55 0.78 Delta EPC log M1-HT -0.17±1.98* −0.12±1.30* −1.15±1.18# 0.2195 0.44 0.32 ACR – acute cellular rejection; AMR or – acute antibody-mediated rejection; EPC log – endothelial progenitor cells after logarithmic transformation; HT – within 24 hours post-transplantation; M1 – at 1-month post-transplantation; Delta EPC log M1-HT – difference in EPC log between M1 and HT. #p=0.0003 for the difference between M1 vs HT; *p=ns for the difference between M1 vs HT; ^pP – for the difference among the groups. Changes in EPC level post-HT Conclusions Early reduction of EPC levels was predictive of a lower risk of ACR or AMR. Greater dynamic changes of EPC during 6 months of observation were associated with a higher risk of rejection suggesting an important role of EPC in the pathological processes post-HT. Thus our findings suggest significant role of EPC post-HT with respect to rejection status. Acknowledgement/Funding Intramural research grant from the Institute of Cardiology

Concomitant overexpression of triple antioxidant enzymes selectively increases circulating endothelial progenitor cells in mice with limb ischaemia.

Endothelial progenitor cells (EPCs) are a group of heterogeneous cells in bone marrow (BM) and blood. Ischaemia increases reactive oxygen species (ROS) production that regulates EPC number and function. The present study was conducted to determine if ischaemia‐induced ROS differentially regulated individual EPC subpopulations using a mouse model concomitantly overexpressing superoxide dismutase (SOD)1, SOD3 and glutathione peroxidase. Limb ischaemia was induced by femoral artery ligation in male transgenic mice with their wild‐type littermate as control. BM and blood cells were collected for EPCs analysis and mononuclear cell intracellular ROS production, apoptosis and proliferation at baseline, day 3 and day 21 after ischaemia. Cells positive for c‐Kit+/CD31+ or Sca‐1+/Flk‐1+ or CD34+/CD133+ or CD34+/Flk‐1+ were identified as EPCs. ischaemia significantly increased ROS production and cell apoptosis and decreased proliferation of circulating and BM mononuclear cells and increased BM and circulating EPCs levels. Overexpression of triple antioxidant enzymes effectively prevented ischaemia‐induced ROS production with significantly decreased cell apoptosis and preserved proliferation and significantly increased circulating EPCs level without significant changes in BM EPC populations, associated with enhanced recovery of blood flow and function of the ischemic limb. These data suggested that ischaemia‐induced ROS was differentially involved in the regulation of circulating EPC population.

Effects of Extra Virgin Olive Oil and Apples Enriched-Dark Chocolate on Endothelial Progenitor Cells in Patients with Cardiovascular Risk Factors: A Randomized Cross-Over Trial.

Background: Endothelial dysfunction has been associated to cardiovascular outcomes in patients with cardiovascular risk factors. Circulating endothelial progenitor cells (EPCs) play an important physiological role for their reparative potential of vascular integrity, but are numerically reduced and functionally impaired in patients with cardiovascular risks. This study assesses the effects of Extra Virgin Olive Oil (EVOO) and apple-enriched dark chocolate intake on the blood levels of EPCs. Methods: Thirty volunteers with cardiovascular risk factors, enrolled in a randomised, crossover, four-weeks trial, received a solid dark chocolate bar (40 g/day) containing 10% EVOO or 2.5% dry apples. Urine samples were analyzed for endogenous metabolites. Circulating EPCs levels, clinical data and anthropometric examinations were collected. Results: 26 volunteers (M/F:14/12, 51 ± 9 years of age) completed the study. Comparison of pre-post intervention revealed a significant increase in EPCs levels associated with EVOO-dark chocolate consumption. Most biochemical parameters were not significantly modified by both chocolates. Conclusions: This study shows that a daily consumption of a non fattening dose of dark chocolate enriched with EVOO improves blood levels of EPCs, a well known surrogate biologic marker for endothelial function.

Pentoxifylline ameliorates chronic stress/high-fat diet-induced vascular wall disease: the role of circulating endothelial progenitor cells.

Depression and cardiovascular disease (CVD) are two faces of one coin. A pro-inflammatory state was previously suggested in the pathology of both diseases. We investigated the effect of chronic administration (2weeks) of imipramine (20mg/kg/day) and pentoxifylline (50mg/kg/day) on behavioral, aortic histological abnormalities, and level of circulating endothelial progenitor cells (CEPCs) in peripheral blood of male Wistar rats exposed to chronic mild stress (CMS) and high-fat diet. Exposure to CMS and high-fat diet induced a depressive-like behavior alongside aortic immunohistochemical changes associated with an increase in aortic TNF-α level. Markers of CEPCs, VEGFR-2 and CD133, were significantly disturbed in aortic sections, as compared to control animals and those exposed to CMS while fed high-fat diet, although flowcytometric analysis did not show any significant changes in the level of CEPCs in peripheral blood. Chronic pentoxifylline treatment was more effective in ameliorating the histological changes and endothelial damage compared to imipramine. Pro-inflammatory cytokines-induced disturbances in CEPCs could constitute a plausible link between depression and atherosclerotic cardiovascular disease. Current antidepressants reduce symptoms of depression without tackling the underlying link between it and cardiovascular disease. Targeting pro-inflammatory cytokines might open a new therapeutic approach to alleviate depression and reduce the risk of mortality from cardiovascular disease.

Atorvastatin Protects Against Cerebral Aneurysmal Degenerative Pathology by Promoting Endothelial Progenitor Cells (EPC) Mobilization and Attenuating Vascular Deterioration in a Rat Model.

BackgroundEndothelial injury is the early pathological change of cerebral aneurysm (CA) formation. In addition to its lipid-lowering activity, atorvastatin (ATR) also reportedly promotes vascular repair via mobilizing endothelial progenitor cells (EPC). Here, we investigated the influence of ATR on vascular worsening after CA induction in rats.Material/MethodsAdult male Sprague-Dawley rats were randomly assigned to 3 groups: a control (CTR) group, a CA group, and a CA+ATR treatment group. Circulating EPC level and hematological and lipid profiles were measured 3 months after CA induction. Verhoeff-Van Gieson staining and transmission electron microscopy were performed to assess pathological changes in the artery wall. RT-PCR was also performed to evaluate the expression of inflammation-related genes in the aneurysmal wall.ResultsATR significantly restored the impaired level of circulating EPC without changing hematological and lipid profiles 3 months after CA induction. ATR markedly inhibited endothelial injury, media thinning, and CA enlargement, accompanied by reduced vascular inflammation.ConclusionsOur preliminary results demonstrate that the mobilization of EPC and improvement of endothelial function by ATR contribute to the prevention of cerebral aneurysm. Further studies are warranted to investigate the detailed mechanism.