Circulating Endothelial Progenitor Cells in Patients with Heart Failure with Preserved versus Reduced Ejection Fraction.

BACKGROUND: Heart failure with preserved ejection fraction (HFpEF) is a common clinical entity, with a mechanism that appears to involve endothelial dysfunction of the cardiac microcirculation. Endothelial progenitor cells (EPC) are bone marrow derived cells that are able to differentiate into functional endothelial cells and participate in endothelial surface repair. OBJECTIVES: To compare the level and function of EPCs in patients with HFpEF compared with heart failure with reduced ejection fraction (HFrEF) and control subjects. METHODS: We enrolled 21 patients with HFpEF (LVEF ≥ 50%, age 74.5 ± 9.9 years, 43% men, 48% diabetes), 20 patients with HFrEF (LVEF < 40%, age 70 ± 11.5 years, 90% men, 60% diabetes), and 11 control subjects with cardiovascular risk factors (age 53.3 ± 6.1years, 90% men, 64% diabetes). Circulating EPC levels were evaluated by expression of vascular endothelial growth factor receptor-2 (VEGFR-2), CD34, and CD133 by flow-cytometry. EPCs colony forming units (CFUs) were quantified after 7 days in culture. RESULTS: The proportion of cells that co-expressed VEGFR-2 and CD34 or VEGFR-2 and CD133 was similar among the HFpEF and HFrEF groups, and significantly lower than in the control group. The number of EPC-CFUs was also similar among the two heart failure groups and significantly lower than the control group. CONCLUSIONS: Patients with HFpEF, like HFrEF, have significant reduction in EPC level and function.

Vascular Regenerative Capacity and the Obesity Paradox in Coronary Artery Disease.

[Figure: see text].

Endothelial Progenitor Cell CD34+ and CD133+ Concentrations and Soluble HLA-G Concentrations During Pregnancy and in Cord Blood in Undifferentiated Connective Tissue Diseases Compared to Controls.

The objective of this study is to evaluate endothelial progenitor cells (EPCs) CD34+ CD133- and CD34+ CD133+ and soluble HLA-G (sHLA-G) concentrations among undifferentiated connective tissue disease (UCTD) subjects, compared to controls, during pregnancy and in cord blood. This is a case-control study including 29 controls and 29 UCTDs. CD34+ CD133-, CD34+ CD133+, and sHLA-G concentrations were detected in maternal plasma and in cord blood. This study was approved by the Medical-Ethical Committee of our Institution (Current Research Project N. 901-rcr2017i-23 of IRCCS Foundation Policlinico San Matteo of Pavia). Circulating CD34+ CD133- and CD34+ CD133+ counts and sHLA-G (soluble human leucocyte antigen G) concentrations in maternal peripherical blood were higher in UCTD compared to those in controls in first and third trimester of pregnancy and at delivery (p < 0.001). Maternal CD34+ CD133- and CD34+ CD133+ counts were strongly and significantly correlated in UCTD (Spearman's rho = 0.79, p < 0.0001) but not in controls (Spearman's rho = 0.10, p = 0.35). Cord blood CD34+ CD133- and CD34+ CD133+ median counts and median sHLA-G concentrations were higher among UCTD subjects than in controls (p < 0.001). Cord blood CD34+ and CD133+ counts were inversely and significantly correlated with sHLA-G concentrations among UCTDs, but not in controls. Early UCTD is characterized by increased EPC levels in maternal plasma and in cord blood and higher levels of sHLA-G, compared to controls. Data suggest that fetoplacental unit plays an independent role in the EPC response to a systemic autoimmune disease.

Periodontitis and Tooth Loss Have Negative Systemic Impact on Circulating Progenitor Cell Levels: A Clinical Study.

The aim of the present study was to investigate the association and impact of periodontitis and tooth loss on a subtype of endothelial progenitor cell (EPC) levels (CD133+/KDR+). Furthermore, the objective was to determine if the periodontal status influenced CD133+/KDR+ levels. In all, 88 patients with periodontitis and 79 healthy controls (HCs) were enrolled in the study. Enrolled patients were examined and characterized by clinical and blood sample analysis. Spearman's correlation test was applied in order to assess the interdependence between CD133+/KDR+ levels and all periodontal parameters. In order to estimate a statistically significant trend (p-trend) for ordered CD133++/KDR+ quartiles, the Jonckheere-Terpstra test was applied for all variables. Patients in the periodontitis group presented significantly lower CD133+/KDR+ levels (66.4 (45.5-269.6 cells/µL)) compared to the HC group (76.7 (24.3-313.2 cells/µL), p < 0.001). Lower CD133+/KDR+ levels negatively correlated with C-reactive protein (CRP), with the number of teeth, and with all periodontal parameters (p < 0.001). Moreover, there was a proportional increase in CD133+/KDR+ levels with a progressive increase in number of teeth (p-trend < 0.001), while there was a proportional decrease in CD133+/KDR+ levels with a proportional increase in clinical attachment level (CAL, p-trend = 0.003), probing depth (PD, p-trend = 0.007), and bleeding sites (bleeding on probing (BOP), p-trend < 0.001) as an extent measure of periodontitis. This study demonstrated that patients with periodontitis presented significantly lower CD133+/KDR+ levels compared to HCs. Moreover, all patients presented an increase in the CD133+/KDR+ EPC levels with an extended level of periodontitis and tooth loss.

Mediterranean, but not lacto-ovo-vegetarian, diet positively influence circulating progenitor cells for cardiovascular prevention: The CARDIVEG study.

AIM: To evaluate the possible association between dietary habits and progenitor cells using data obtained from a randomized crossover trial using two different diets, lacto-ovo-vegetarian (VD) and Mediterranean (MD), the CARDIVEG study. METHODS AND RESULTS: Eighty clinically healthy subjects with a low-to-moderate cardiovascular risk profile (61 F; 19 M; mean age: 50.7 ± 11.6 years) were randomly assigned to isocaloric VD and MD diets lasting three months each, and then crossed. The two diets showed no effects on endothelial progenitor cells and circulating endothelial cells but opposite effects on circulating progenitor cells. In fact, VD determined significant (p < 0.05) and negative changes on circulating progenitor cells, with an average geometric variation of -130 cells/106 events for CD34+/CD45-/dim, -80 cells/106 events for CD133+/CD45-/dim, and -84 cells/106 events for CD34+/CD133+/CD45-/dim while MD determined significant (p < 0.05) and positive changes for CD34+/CD45-/dim levels, with a geometric mean increase of +54 cells/106 events. No significant correlations were observed between changes in progenitor cells and changes in inflammatory parameters during the VD phase. On the other hand, during the MD phase negative correlations between changes of CD34+/CD45-/dim and interleukin-6 (R = -0.324; p = 0.004) as well as interleukin-8 (R = -0.228; p = 0.04) and monocyte chemotactic protein-1 (R = -0.277; p = 0.01), were observed. These correlations remained significant also after adjustment for confounding factors only for CD34+/CD45-/dim and interleukin-6 (ß = -0.282; p = 0.018) and monocyte chemotactic protein-1 (ß = -0.254; p = 0.031). CONCLUSIONS: MD, but not VD, reported a significant and positive effect on circulating progenitor cells in a group of subjects at low-to-moderate cardiovascular risk, probably acting through the modulation of inflammatory parameters.

CD133+/C-kit+Lin- endothelial progenitor cells in fetal circulation demonstrate impaired differentiation potency in severe preeclampsia.

OBJECTIVES: Individuals delivered from preeclamptic pregnancies exhibit a long-term increased risk of developing cardiovascular and metabolic diseases, likely caused by aberrant fetal cell reprogramming incurred in utero. The present study investigated the functional impairment and epigenetic changes exhibited by endothelial progenitor cells derived from offspring born to preeclamptic pregnancies. STUDY DESIGN: The capacity of CD133+/C-kit+/Lin- (CKL-) human umbilical cord blood endothelial progenitor cells (EPCs) derived from gestationally matched normal and preeclamptic (n = 10 each) pregnancies to differentiate to form outgrowth endothelial cells (OECs) was assessed by observing both their morphology, and the number and size of generated OECs colonies. Likewise, OECs angiogenic function was evaluated via migration, adhesion, and tube-formation assays. EPCs from preeclampsia were cultured in normal-, and preeclampsia-derived serum-conditioned media to assess the effects of environmental factors on EPC differentiation potency and OEC angiogenic function, and finally, EPCs H3K4, H3K9, and H3K27 trimethylation levels were assayed. RESULTS: The preeclampsia-derived CKL- EPCs exhibited decreased H3K4 and H3K9 trimethylation levels, significantly delayed differentiation times, and a significant reduction in both their number of generated OECs colonies, and exhibited reduced OECs migration, adhesion, and tube formation activities compared to those achieved by the normal-derived EPCs. Interestingly, the reduced differentiation potency of the preeclampsia-derived EPCs was not rescued via exposure to normal serum. CONCLUSIONS: Exposure to preeclampsia significantly and irreversibly reduced CKL- EPC differentiation potency and OEC angiogenic function, likely reflecting incurred irreversible epigenetic changes.

Elevated Inflammatory Parameter Levels Negatively Impact Populations of Circulating Stem Cells (CD133+), Early Endothelial Progenitor Cells (CD133+/VEGFR2+), and Fibroblast Growth Factor in Stroke Patients.

BACKGROUND: Endothelial Progenitor Cells (EPCs) are important players in neovascularization, mobilized through signalling by Angiogenic Growth Factors (AGFs) such as Vascular Endothelial Growth Factor (VEGF) and fibroblast growth factor (FGF). In vitro, inflammatory parameters impair the function and influence of EPCs on AGFs. However, this connection is not clear in vivo. To understand the mechanisms of augmented arteriogenesis and angiogenesis in acute ischemic stroke (AIS) patients, we investigated whether circulating stem cells (CD133+), early endothelial progenitor cells (CD133+/VEGFR2+), and endothelial cells (ECs; CD34¯/CD133¯/VEGFR2+) were increasingly mobilized during AIS, and whether there were correlations between EPC levels, growth factor levels and inflammatory parameters. METHODS: Data on demographics, classical vascular risk factors, neurological deficit information (assessed using the National Institutes of Health Stroke Scale), and treatment were collected from 43 consecutive AIS patients (group I). Risk factor control patients (group II) included 22 nonstroke subjects matched by age, gender, and traditional vascular risk factors. EPCs were measured by flow cytometry and the populations of circulating stem cells (CD133+), early EPCs (CD133+/VEGFR2+), and ECs (CD34¯/CD133¯/VEGFR2+) were analysed. Correlations between EPC levels and VEGF and FGF vascular growth factor levels as well as the influence of inflammatory parameters on EPCs and AGFs were assessed. RESULTS: Patient ages ranged from 54 to 92 years (mean age 75.2 ± 11.3 years). The number of circulating CD34¯/CD133¯/VEGF-R2+ cells was significantly higher in AIS patients than in control patients (p < 0.05). VEGF plasma levels were also significantly higher in AIS patients compared to control patients on day 7 (p < 0.05). FGF plasma levels in patients with AIS were significantly higher than those in the control group on day 3 (p < 0.05). There were no correlations between increased VEGF and FGF levels and the number of CD133+, CD133+/VEGFR2+, or CD34¯/CD133¯/VEGFR2+ cells. Leukocyte levels, FGF plasma levels, and the number of early EPCs were negatively correlated on day 3. High sensitivity C-reactive protein levels and the number of CD133+ and CD133+/VEGFR2+ cells were negatively correlated on day 7. In addition, there was a negative correlation between fibrinogen levels and FGF plasma levels as well as the number of early EPCs (CD133+/VEGFR2+). CONCLUSION: AIS patients exhibited increased numbers of early EPCs (CD133+/VEGFR2+) and AGF (VEGF and FGF) levels. A negative correlation between inflammatory parameters and AGFs and EPCs indicated the unfavourable influence of inflammatory factors on EPC differentiation and survival. Moreover, these correlations represented an important mechanism linking inflammation to vascular disease.

CD34+ and CD34+VEGFR2+ cells in poorly controlled hypertensive patients.

CD34+ and CD34+VEGFR2+ cells participate in the repair of damaged endothelium and vascular remodelling. As their number and activity change due to the development of cardiovascular diseases, they are recognised as useful markers of cardiovascular health. As ineffective blood pressure control concerns high percentage of hypertensive patients, the purpose of our study was to investigate if proportions of various CD34+ and CD34+VEGFR2+ populations change due to hypertension occurrence and the effectiveness of the therapy. We also wanted to establish which factors impact these cells. Circulating populations of CD34+ and CD34+VEGFR2+ cells were analysed in peripheral blood samples by flow cytometry. Serum/plasma levels of sICAM-1, sVCAM-1 and vWF were determined using immunoenzymatic assay. We did not observe differences in CD34+ populations, but proportions of CD34+VEGFR2+ (p = 0.006), CD34+VEGFR2+CD133+ (p = 0.002) and CD34+VEGFR2+c-Kit+ (p = 0.003) cells were reduced in patients with poorly controlled blood pressure. We have also established that these cells exhibit connections with age, blood pressure and sICAM-1 serum levels. However, multiparametric regression analyses did not indicate any of the analysed variables as independent factors affecting CD34+VEGFR2+ populations. CD34+VEGFR2+, CD34+VEGFR2+CD133+ and CD34+VEGFR2+c-Kit+ cells are reduced in poorly controlled hypertensive patients, which may be partially connected with increased cardiovascular complications and mortality observed in this group.

Prolonged incubation with Metformin decreased angiogenic potential in human bone marrow mesenchymal stem cells.

Metformin is commonly prescribed as a hypoglycemic agent following the onset of type 2 diabetes mellitus. This study aimed to investigate pro- and/or anti-angiogenic effects of Metformin on human bone marrow mesenchymal stem cells. Cells were incubated with different doses of Metformin including 0.5, 1, 10, 50, 100, 200 and 500 µM for 14 days. Cell viability and total fatty acids profile were examined by MTT and gas chromatography methods. Differentiation of cells to endothelial lineage was studied by monitoring the expression of VEGFR-2 and Tie-2 receptors and VE-cadherin via real-time PCR and western blotting. Angiogenic potential and migration of cells were assessed by tubulogenesis and Transwell migration assays. PCR array was performed to analyze mTOR signaling. CD133+ and VEGFR-2+ cells were detected in blood samples of non-diabetic control, diabetic subjects and diabetics received Metformin. Metformin dose-dependently reduced cell survival. Decreased content of palmitate and oleate coincided increased level of stearate, palmitoleate, and linoleate (p < 0.05). Metformin decreased the angiogenic potential of cells by decreasing VEGFR-2 and Tie-2 expression (p < 0.05). The protein level of VE-cadherin decreased in cells received Metformin. Compared to the control, Metformin blunted the expression of VEGF subtypes and directed cells to energy status by induction of PRKAA1, PRKAB2, and PRKAG1 genes (p < 0.05). Non-significant differences were observed regarding the number of CD133 and VEGFR-2 cells in blood samples (p > 0.05). These data support a notion that Metformin could blunt the angiogenic behavior of human mesenchymal stem cells by modulating mTOR signaling pathway.

The evaluation of circulating endothelial progenitor cells and related angiogenic markers as prognostic factors in soft-tissue tumors.

INTRODUCTION: Neovascularisation is a critical step in the progression of malignant tumors. Circulating endothelial progenitor cells (cEPC) have been proposed as surrogate markers of vasculogenesis in malignancies. In this project, we studied the impact of tumor-specific therapy on cEPC and associated angiogenic factors in patients with soft tissue tumors. MATERIALS AND METHODS: Fifty-three patients with soft tissue tumors (25 soft tissue sarcomas, 19 GIST, 9 desmoids) and 15 healthy controls were included. Blood samples were obtained at two time points, before and 8 weeks after start of tumor-specific therapy. Peripheral blood mononuclear cells (PBMCs) were isolated. cEPCs were characterised as CD34+, CD133+, CD45dim, CD31+ and vascular endothelial growth factor 2 (VEGFR-2) positive cells. Serum concentrations of VEGF-A and angiopoetin-2 were determined by enzyme-linked immunosorbent assay. RESULTS: VEGF-A and Ang-2 concentrations were significantly higher in tumor patients than in healthy controls in both samples (p < .01). Sarcoma patients with progressive disease developed a significant increase in cEPC levels between the two blood samples compared to those with stable disease (p = .002). GIST patients with progressive tumor or metastatic disease showed significant increase in VEGF-A values (p = .01). DISCUSSION: The pre-treatment values of the angiogenic markers did not correlate with the clinical course of the disease. However, cEPCs levels were significantly higher in sarcoma patients with progressive disease compared to those with stable disease and should be further evaluated as early markers of disease progression in sarcoma patients. VEGF-A and angiopoetin-2 clearly play a role as mediators of the vasculogenesis contributing to tumor progression.

Mobilization of endothelial progenitor cell in patients with acute ischemic stroke.

Endothelial progenitor cells (EPCs) have important effect in tissue repair in ischemic organs. The present study was conducted to demonstrate the mobilization of EPCs and its possible mechanism after acute ischemic stroke (AIS). A total of 148 individuals were examined, including 106 patients with ischemic stroke and 42 healthy controls. Seventy-one patients with imaging-confirmed AIS were examined at days 1, 7, 14, and 21 after stroke onset. Circulating EPCs were quantified by flow cytometry using CD133 and KDR surface markers. Serum stromal cell-derived factor-1 (SDF-1) concentrations were determined by enzyme-linked immunosorbent assay. Patients with AIS had significantly lower EPC level than that in the controls (0.022 ± 0.013 vs 0.051 ± 0.020; p < 0.01). This difference did not remain significant after adjusting for risk factors at multivariate analysis. Blood pressure, triglyceride, low-density lipoprotein (LDL), and fasting blood sugar were inversely correlated with EPC levels (p < 0.01). Systolic blood pressure and LDL remained independent predictors of baseline EPC levels. The number of circulating EPCs increased on day 7 after AIS, reached a peak on day 14, and decreased on day 21. The concentration of SDF-1 had similar changes. The increment of EPCs was correlated with the infarct volume (r = 0.708; p = 0.006) and SDF-1 concentration on day 14 (r = 0.714; p < 0.001). Baseline EPC level in patients with AIS reflects the cumulative vascular endothelial damage. EPCs could be mobilized into peripheral circulation in response to stroke stress. This mobilization was associated with the increased expression of SDF-1.

Prognostic value of CD133+ CD54+ CD44+ circulating tumor cells in colorectal cancer with liver metastasis.

In the previous study, we had showed the expression of CD133+ CD54+ CD44+ cellular subpopulation of circulating tumor cells (CTCs) was significantly associated with liver metastasis of colorectal cancer (CRC). This study aimed to explore whether this subpopulation of CTCs have a prognostic value in CRC patients. Flow cytometry was used to detect the expression of cellular subpopulations of CTCs with CD133, CD54, and CD44 in 152 CRC patients, between December 2013 and October 2014. The impact of clinicopathological factors and the expression of cellular subpopulations of CTCs on overall survival were then analyzed. CRC patients with liver metastases who underwent resection of the primary tumor accompanied by surgical treatment for metastasis had a better survival than other patients (P < 0.001). The liver metastatic CRC patients with high expression of CD133+ CD54+ (P < 0.001), CD133- CD54+ (P = 0.004), and CD133+ CD44+ CD54+ (P = 0.003) cellular subpopulations of CTCs had a worse survival than those patients with low expression. Multivariable survival analyses identified carcinoembryonic antigen levels (hazard ratio [HR] = 3.056; 95% confidence interval [CI] = 1.354-6.897; P = 0.007), treatment strategy (HR = 0.212; 95% CI = 0.056-0.808; P = 0.023), and CD133+ CD44+ CD54+ cellular subpopulation of CTCs (HR = 6.459; 95% CI = 1.461-28.558; P = 0.014) as independent prognostic factors for CRC patients with liver metastasis. CD133+ CD44+ CD54+ cellular subpopulation of CTCs has a prognostic value in CRC patients with liver metastasis, especially in the survival of CRC patients with liver metastasis who did not undergo surgical treatment for metastasis.

Endothelial Progenitor Cell Biology and Vascular Recovery Following Transradial Cardiac Catheterization.

BACKGROUND: Transradial catheterization is associated with radial artery injury and vasomotor dysfunction and represents an accessible model of acute vascular injury in humans. We characterized vascular injury and functional recovery to understand the role of circulating endothelial progenitor cells in vascular repair. METHODS AND RESULTS: In 50 patients (aged 64±10 years, 70% male) undergoing transradial cardiac catheterization, radial artery injury was assessed by optical coherence tomography and examination of explanted vascular sheaths. Flow- and nitrate-mediated dilatation of the radial artery was assessed in both arms at baseline, at 24 hours, and at 1, 4, and 12 weeks. Circulating endothelial progenitor cell populations were quantified using flow cytometry. Late endothelial outgrowth colonies were isolated and examined in vitro. Optical coherence tomography identified macroscopic injury in 12 of 50 patients (24%), but endothelial cells (1.9±1.2×104 cells) were isolated from all arterial sheaths examined. Compared with the noncatheterized radial artery, flow-mediated vasodilatation was impaired in the catheterized artery at 24 hours (9.9±4.6% versus 4.1±3.1%, P<0.0001) and recovered by 12 weeks (8.1±4.9% versus 10.1±4.9%, P=0.09). Although the number of CD133+ cells increased 24 hours after catheterization (P=0.02), the numbers of CD34+ cells and endothelial outgrowth colonies were unchanged. Migration of endothelial cells derived from endothelial outgrowth colonies correlated with arterial function before catheterization but was not related to recovery of function following injury. CONCLUSIONS: Transradial cardiac catheterization causes endothelial denudation, vascular injury, and vasomotor dysfunction that recover over 12 weeks. Recovery of vascular function does not appear to be dependent on the mobilization or function of endothelial progenitor cells. CLINICAL TRIAL REGISTRATION: URL: https://www.clinicaltrials.gov. Unique identifier: NCT02147119.

Endothelial to haematopoietic transition contributes to pulmonary arterial hypertension.

AIMS: The pathogenic mechanisms of pulmonary arterial hypertension (PAH) remain unclear, but involve dysfunctional endothelial cells (ECs), dysregulated immunity and inflammation in the lung. We hypothesize that a developmental process called endothelial to haematopoietic transition (EHT) contributes to the pathogenesis of pulmonary hypertension (PH). We sought to determine the role of EHT in mouse models of PH, to characterize specific cell types involved in this process, and to identify potential therapeutic targets to prevent disease progression. METHODS AND RESULTS: When transgenic mice with fluorescence protein ZsGreen-labelled ECs were treated with Sugen/hypoxia (Su/Hx) combination to induce PH, the percentage of ZsGreen+ haematopoietic cells in the peripheral blood, primarily of myeloid lineage, significantly increased. This occurrence coincided with the depletion of bone marrow (BM) ZsGreen+ c-kit+ CD45- endothelial progenitor cells (EPCs), which could be detected accumulating in the lung upon PH-induction. Quantitative RT-PCR based gene array analysis showed that key transcription factors driving haematopoiesis were expressed in these EPCs. When transplanted into lethally irradiated recipient mice, the BM-derived EPCs exhibited long-term engraftment and haematopoietic differentiation capability, indicating these EPCs are haemogenic in nature. Specific inhibition of the critical haematopoietic transcription factor Runx1 blocked the EHT process in vivo, prevented egress of the BM EPCs and ultimately attenuated PH progression in Su/Hx- as well as in monocrotaline-induced PH in mice. Thus, myeloid-skewed EHT promotes the development of PH and inhibition of this process prevents disease progression in mouse models of PH. Furthermore, high levels of Runx1 expression were found in circulating CD34+ CD133+ EPCs isolated from peripheral blood of patients with PH, supporting the clinical relevance of our proposed mechanism of EHT. CONCLUSION: EHT contributes to the pathogenesis of PAH. The transcription factor Runx1 may be a novel therapeutic target for the treatment of PAH.

CD133+ cells are associated with ADIPOCYTOKINES and endothelial dysfunction in hemodialysis patients.

BACKGROUND: Hemodialysis (HD) patients have increased risk of cardiovascular disease (CVD). Impaired stem cell health and adipocytokine metabolism may play important roles in the complex pathophysiological mechanisms of CVD in this patient population. We aimed to investigate the relationships between CD133+ cell counts, adipocytokines and parameters of endothelial dysfunction and atherosclerosis in HD patients. METHODS: In 58 chronic HD patients (male/female:28/30, mean age:58 ± 14 years), serum levels of interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), leptin, adiponectin and resistin were measured by ELISA. Left ventricular mass index (LVMI), carotid intima-media thickness (CIMT), flow-mediated dilatation (FMD) of the brachial artery were measured. CD133+ cells were counted by flow cytometry (BD FACSCalibur-BD Bioscience,CA). RESULTS: CD133+ cell counts were inversely associated with FMD (r = -0.39, p = 0.007) and positively correlated with serum resistin (r = 0.45, p < 0.001) and serum TNF-α (r = 0.31, p = 0.02). Serum leptin levels were higher in high CD133 group compared to low CD133 group [32.37(12.74-72.29) vs 15.50(5.38-37.12)ng/mL, p = 0.03]. Serum leptin levels were correlated with TNF-α(r = 0.35, p = 0.009). Serum adiponectin levels were negatively correlated with serum leptin (r = -0.28, p = 0.03). Serum resistin levels were associated with TNF-α (r = 0.54, p < 0.001) and leptin (r = 0.29, p = 0.03). Serum IL-6 levels were significantly associated with LVMI (r = 0.31, p = 0.03). Serum IL-6 levels were significantly higher in patients with carotid plaque compared to patients without plaque [12.75(9.91-28.68) vs 8.27(5.97-14.04) pg/mL, p = 0.02]. In multiple linear regression analysis to determine the factors predicting LogFMD; dialysis vintage, LVMI and LogCD133+ cell counts were included as independent variables(R = 0.57, adjusted R-square = 0.27, p = 0.001). CD133+ cell count and LVMI were found to significantly predict FMD (p = 0.03 and p = 0.04 respectively). CONCLUSION: CD133+ cells were associated with inflammation and endothelial dysfunction in HD patients. Serum leptin, resistin and TNF-α levels were positively related to CD133+ cell count. Impaired regulation of undifferentiated stem cells and adipocytokines might contribute to endothelial dysfunction in HD patients.

Effects of Chronic Exercise on Endothelial Progenitor Cells and Microparticles in Professional Runners.

BACKGROUND: The effects of chronic exposure to exercise training on vascular biomarkers have been poorly explored. OBJECTIVE: Our study aimed to compare the amounts of endothelial progenitor cells (EPCs), and endothelial (EMP) and platelet (PMP) microparticles between professional runners and healthy controls. METHODS: Twenty-five half-marathon runners and 24 age- and gender-matched healthy controls were included in the study. EPCs (CD34+/KDR+, CD133+/KDR+, and CD34+/CD133+), EMP (CD51+) and PMP (CD42+/CD31+) were quantified by flow-cytometry. All blood samples were obtained after 12 h of fasting and the athletes were encouraged to perform their routine exercises on the day before. RESULTS: As compared with controls, the CD34+/KDR+ EPCs (p=0.038) and CD133+/KDR+ EPCs (p=0.018) were increased, whereas CD34+/CD133+ EPCs were not different (p=0.51) in athletes. In addition, there was no difference in MPs levels between the groups. CONCLUSION: Chronic exposure to exercise in professional runners was associated with higher percentage of EPCs. Taking into account the similar number of MPs in athletes and controls, the study suggests a favorable effect of exercise on these vascular biomarkers.

Reduced circulating stem cells associate with excess fasting and post-load NEFA exposure in healthy adults with normal glucose tolerance.

BACKGROUND AND AIMS: Reduced levels of circulating stem cells (CSCs) predict cardiovascular events and death, but the factors underlying variability of CSCs in healthy adults are mostly unknown. Previous studies detected associations of CSCs with glucose tolerance or insulin resistance, while the role of fatty acids has been overlooked. We herein aimed to describe in better detail the metabolic abnormalities associated with a reduced CSC level. METHODS: This was a cross-sectional study on 94 healthy male and female individuals with normal glucose tolerance, aged 18-65 years. All participants underwent an oral glucose tolerance test (OGTT) with blood samples collected at 0, 10, 20, 30, 60, 90 and 120 min. Mathematical models were applied to plasma glucose, insulin, C-peptide and non-esterified fatty acids (NEFA) concentrations. CSCs were defined as CD34+ or CD133+. RESULTS: Participants (mean ± SEM age 43.8 ± 0.7; 41% males) were divided according to CSC levels below (low) or above (high) the median value and metabolic parameters were compared. There was no significant baseline difference between groups except for higher concentrations of fasting NEFA in subjects with low CSCs. Upon OGTT, individuals with low CSCs had higher area under curve (AUC) of NEFA (p < 0.001) and no significant differences in glucose, insulin and C-peptide. Several insulin sensitivity and beta cell function indexes were not significantly different, except for a decrease in the disposition index (DI) in subjects with low CSCs. CSCs were associated with excess NEFA levels independently from age and DI. CONCLUSIONS: We show for the first time that, in healthy adults with normal glucose tolerance, low CSCs are strongly associated with excess NEFA exposure. The pathophysiological consequence of this association needs to be interpreted in view of the prognostic role of CSCs. Future studies should explore whether excess NEFA and low CSCs and are causally interconnected.

Effects of Chronic Exercise on Endothelial Progenitor Cells and Microparticles in Professional Runners / Efeitos de Exercício Crônico Sobre Células Progenitoras Endoteliais e Micropartículas em Corredores Profissionais

Abstract Background: The effects of chronic exposure to exercise training on vascular biomarkers have been poorly explored. Objective: Our study aimed to compare the amounts of endothelial progenitor cells (EPCs), and endothelial (EMP) and platelet (PMP) microparticles between professional runners and healthy controls. Methods: Twenty-five half-marathon runners and 24 age- and gender-matched healthy controls were included in the study. EPCs (CD34+/KDR+, CD133+/KDR+, and CD34+/CD133+), EMP (CD51+) and PMP (CD42+/CD31+) were quantified by flow-cytometry. All blood samples were obtained after 12 h of fasting and the athletes were encouraged to perform their routine exercises on the day before. Results: As compared with controls, the CD34+/KDR+ EPCs (p=0.038) and CD133+/KDR+ EPCs (p=0.018) were increased, whereas CD34+/CD133+ EPCs were not different (p=0.51) in athletes. In addition, there was no difference in MPs levels between the groups. Conclusion: Chronic exposure to exercise in professional runners was associated with higher percentage of EPCs. Taking into account the similar number of MPs in athletes and controls, the study suggests a favorable effect of exercise on these vascular biomarkers.

Resumo Fundamento: Os efeitos da exposição crônica ao exercício sobre biomarcadores vasculares foram pouco estudados. Objetivo: Nosso estudo teve como objetivo comparar as quantidades de células progenitoras endoteliais (CPEs), e de micropartículas endoteliais (MPEs) e plequetárias (MPPs) de corredores profissionais com controles sadios. Métodos: Vinte e cinco corredores de meia maratona e 24 controles pareados quanto à idade e ao sexo foram incluídos no estudo. CPEs (CD34+/KDR+, CD133+/KDR+ e CD34+/CD133+), MPE (CD51+) e MPPs (CD42+/CD31+) foram quantificadas por citometria de fluxo. Todas as amostras de sangue foram obtidas após 12 horas de jejum, e os atletas foram incentivados a realizar seus exercícios de rotina no dia anterior à coleta. Resultados: Em comparação aos controles, CPEs CD34+/KDR+ (p=0,038) e CD133+/KDR+ (p=0,018) estavam aumentados, e CPEs CD34+/CD133+ não foram diferentes (p=0,51) nos atletas. As concentrações de MP não diferiram entre os grupos. Conclusão: A exposição crônica ao exercício em corredores profissionais associou-se a uma maior porcentagem de CPEs. Considerando o número similar de MPs entre atletas e controles, o estudo sugere um efeito favorável do exercício sobre esses biomarcadores vasculares.

The Protein Content of Extracellular Vesicles Derived from Expanded Human Umbilical Cord Blood-Derived CD133+ and Human Bone Marrow-Derived Mesenchymal Stem Cells Partially Explains Why both Sources are Advantageous for Regenerative Medicine.

Adult stem cells have beneficial effects when exposed to damaged tissue due, at least in part, to their paracrine activity, which includes soluble factors and extracellular vesicles (EVs). Given the multiplicity of signals carried by these vesicles through the horizontal transfer of functional molecules, human mesenchymal stem cell (hMSCs) and CD133+ cell-derived EVs have been tested in various disease models and shown to recover damaged tissues. In this study, we profiled the protein content of EVs derived from expanded human CD133+ cells and bone marrow-derived hMSCs with the intention of better understanding the functions performed by these vesicles/cells and delineating the most appropriate use of each EV in future therapeutic procedures. Using LC-MS/MS analysis, we identified 623 proteins for expanded CD133+-EVs and 797 proteins for hMSCs-EVs. Although the EVs from both origins were qualitatively similar, when protein abundance was considered, hMSCs-EVs and CD133+-EVs were different. Gene Ontology (GO) enrichment analysis in CD133+-EVs revealed proteins involved in a variety of angiogenesis-related functions as well proteins related to the cytoskeleton and highly implicated in cell motility and cellular activation. In contrast, when overrepresented proteins in hMSCs-EVs were analyzed, a GO cluster of immune response-related genes involved with immune response-regulating factors acting on phagocytosis and innate immunity was identified. Together our data demonstrate that from the point of view of protein content, expanded CD133+-EVs and hMSCs-EVs are in part similar but also sufficiently different to reflect the main beneficial paracrine effects widely reported in pre-clinical studies using expanded CD133+ cells and/or hBM-MSCs.

Circulating Tumor Cells Expressing Markers of Tumor-Initiating Cells Predict Poor Survival and Cancer Recurrence in Patients with Pancreatic Ductal Adenocarcinoma.

Purpose: Circulating tumor cells (CTCs) have been identified in the blood of patients with pancreatic adenocarcinoma (PDAC), but little is known about the exact phenotype of these cells. We assessed expression of aldehyde dehydrogenase (ALDH), CD133, and CD44 as markers of CTCs with a tumor-initiating cell (TIC) phenotype in patients with PDAC and the relationship of this expression to patient outcomes.Experimental Design: Peripheral blood from 60 consecutive patients with PDAC undergoing surgical resection was obtained and processed using the Isolation by Size of Epithelial Tumor (ISET) method. Immunofluorescence was used to identify CTCs expressing cytokeratin, CD133, CD44, and ALDH.Results: Forty-seven patients (78%) had epithelial CTCs staining positive for pan-cytokeratin and at least one TIC marker. Forty-six patients (77%) had epithelial CTCs that labeled with antibodies to cytokeratin and ALDH. By separate analysis, 34 (57%) had cytokeratin-positive, CD133-positive, and CD44-positive (triple-positive) CTCs, whereas 40 (67%) had cytokeratin-positive, CD133-positive, CD44-negative CTCs. The remaining 13 patients did not have CTCs, as defined by cytokeratin expression. ALDH-positive CTCs and triple-positive CTCs were significantly associated with worse survival by univariate analysis, even when accounting for other significant prognostic factors (all, P ≤ 0.01). ALDH-positive CTCs, triple-positive CTCs, and dual cytokeratin- and CD133-positive CTCs were independent predictors of tumor recurrence by logistic regression analysis and associated with decreased disease-free survival (all, P ≤ 0.03).Conclusions: CTCs labeling with one or more markers of TICs are found in a majority of patients with PDAC and are independently predictive of decreased disease-free and overall survival. Clin Cancer Res; 23(11); 2681-90. ©2016 AACR.