Differentiation potential and functional properties of a CD34­CD133+ subpopulation of endothelial progenitor cells.

Endothelial progenitor cells (EPCs) promote angiogenesis and play an important role in myocardial and vascular repair after ischemia and infarction. EPCs consist of different subpopulations including CD34­CD133+ EPCs, which are precursors of more mature CD34+CD133+ EPCs and functionally more active in terms of homing and endothelial regeneration. In the present study we analyzed the functional and differentiation abilities of CD34­CD133+ EPCs. Isolation of EPC populations (CD34+CD133+, CD34­CD133+) were performed by specific multi­step magnetic depletion. After specific stimulation a significant higher adhesive and migrative capacity of CD34­CD133+ cells could be detected compared to CD34+CD133+ cells (P<0.001, respectively). Next to this finding, not only significantly higher rates of proliferation (P<0.005) were detected among CD34­CD133+ cells, but also a higher potential of cell­differentiation capacity into other cell types. Next to a significant increase of CD34­CD133+ EPCs differentiating into a fibroblast cell­type (P<0.001), an enhancement into a hepatocytic cell­type (P=0.033) and a neural cell­type (P=0.016) could be measured in contrast to CD34+CD133+ cells. On the other hand, there was no significant difference in differentiation into a cardiomyocyte cell­type between these EPC subpopulations (P=0.053). These results demonstrate that EPC subpopulations vary in their functional abilities and, to different degrees, have the capacity to transdifferentiate into unrelated cell­types such as fibroblasts, hepatocytes, and neurocytes. This indicates that CD34­CD133+ cells are more pluripotent compared to the CD34+CD133+ EPC subset, which may have important consequences for the therapy of vascular diseases.

Marathon running increases circulating endothelial- and thrombocyte-derived microparticles.

Background Acute vascular effects of high intensity physical activity are incompletely characterized. Circulating microparticles are cellular markers for vascular activation and damage. Methods Microparticles were analysed in 99 marathon runners (49 ± 6 years, 22% female) of the prospective Berlin Beat of Running study. Blood samples were taken within three days before, immediately after and within two days after the marathon run. Endothelial-derived microparticles were labelled with CD144, CD31 and CD62E, platelet-derived microparticles with CD62P and CD42b, leukocyte-derived microparticles with CD45 and monocyte-derived microparticles with CD14. Results Marathon running induced leukocytosis (5.9 ± 0.1 to 14.8 ± 0.3 109/l, p < 0.0001) and increased platelet counts (239 ± 4.6 to 281 ± 5.9 109/l, p < 0.0001) immediately after the marathon. Blood monocytes increased and lymphocytes decreased after the run ( p < 0.0001). Endothelial-derived microparticles were acutely increased ( p = 0.008) due to a 23% increase of apoptotic endothelial-derived microparticles ( p = 0.007) and returned to baseline within two days after the marathon. Thrombocyte-derived microparticles acutely increased by 38% accompanied by an increase in activated and apoptotic thrombocyte-derived microparticles ( p ≤ 0.0001) each. Both monocyte- and leukocyte-derived microparticles were decreased immediately after marathon run ( p < 0.0001) and remained below baseline until day 2. Troponin T increased from 12 to 32 ng/l ( p < 0.0001) immediately after the run and returned to baseline after two days. Conclusion Circulating apoptotic endothelial- and thrombocyte-derived microparticles increased after marathon running consistent with an acute pro-thrombotic and pro-inflammatory state. Exercise-induced vascular damage reflected by microparticles could indicate potential mechanisms of post-exertional cardiovascular complications. Further studies are warranted to investigate microparticles as markers to identify individuals prone to such complications.

Parvovirus B19-induced vascular damage in the heart is associated with elevated circulating endothelial microparticles.

BACKGROUND: Diagnosis of viral myocarditis is difficult by clinical criteria but facilitated by detection of inflammation and viral genomes in endomyocardial biopsies. Parvovirus B19 (B19V) targets endothelial cells where viral nucleic acid is exclusively detected in the heart. Microparticles (MPs) are released after cell damage or activation of specific cells. We aimed to investigate whether circulating endothelial MPs (EMPs) in human and experimental models of myocarditis are associated with B19V myocarditis. METHODS: MPs were investigated in patients with myocarditis (n = 54), divided into two groups: B19V+ (n = 23) and B19V- (n = 31) and compared with healthy controls (HCTR, n = 25). MPs were also investigated in B19V transgenic mice (B19V-NS1+) and mice infected with coxsackievirus B3 (CVB3). MPs were analyzed with fluorescent activated cell sorting (FACS). RESULTS: In human samples, EMP subpopulation patterns were significantly different in B19V+ compared to B19V- and HCTR (p<0.001), with an increase of apoptotic but not activated EMPs. Other MPs such as platelet- (PMPs) leukocyte-(LMPs) and monocyte-derived MPs (MMPs) showed less specific patterns. Significantly different levels of EMPs were observed in transgenic B19V-NS1+ mice compared with CVB3-infected mice (p<0.001). CONCLUSION: EMP subpopulations are different in B19V+ myocarditis in humans and transgenic B19V mice reflecting vascular damage. EMP profiles might permit differentiation between endothelial-cell-mediated diseases like myocardial B19V infection and other causes of myocarditis.

Red Wine Prevents the Acute Negative Vascular Effects of Smoking.

BACKGROUND: Moderate consumption of red wine is associated with fewer cardiovascular events. We investigated whether red wine consumption counteracts the adverse vascular effects of cigarette smoking. METHODS: Participants smoked 3 cigarettes alone or after drinking a titrated volume of red wine. Clinical chemistry, blood counts, plasma cytokine enzyme-linked immunosorbent assays, immunomagnetic separation of CD14+ monocytes for gene expression analysis, fluorescence-activated cell sorting for microparticles, and isolation of circulating mononuclear cells to measure telomerase activity were performed, and urine cotinine levels were quantified. RESULTS: Compared with baseline, leukocytosis (P = .019), neutrophilia (P <.001), lymphopenia (P <.001), and eosinopenia (P = .008) were observed after only smoking. Endothelial and platelet-, monocyte-, and leukocyte-derived microparticles (P <.001 each) were elevated. In monocytes, messenger RNA expression of interleukin (IL)-6 (2.6- ± 0.57-fold), tumor necrosis factor alpha (2.2- ± 0.62-fold), and IL-1b (2.3- ± 0.44-fold) were upregulated, as was IL-6 (1.2 ± 0.12-fold) protein concentration in plasma. Smoking acutely inhibited mononuclear cell telomerase activity. Markers of endothelial damage, inflammation, and cellular aging were completely attenuated by red wine consumption. CONCLUSION: Cigarette smoke results in acute endothelial damage, vascular and systemic inflammation, and indicators of the cellular aging processes in otherwise healthy nonsmokers. Pretreatment with red wine was preventive. The findings underscore the magnitude of acute damage exerted by cigarette smoking in "occasional lifestyle smokers" and demonstrate the potential of red wine as a protective strategy to avert markers of vascular injury.

WITHDRAWN: Corrigendum to "Red wine prevents the acute negative vascular effects of smoking".

Available online This article has been withdrawn at the request of the author(s) and/or editor. The Publisher apologizes for any inconvenience this may cause. The full Elsevier Policy on Article Withdrawal can be found at http://www.elsevier.com/locate/withdrawalpolicy.

Evidence of autoantibodies against cardiac troponin I and sarcomeric myosin in peripartum cardiomyopathy.

Peripartum cardiomyopathy (PPCM) is a major cause of pregnancy-related maternal heart failure that develops towards the end of pregnancy or in the months following delivery. In small retrospective case series, autoimmune responses in the pathogenesis of PPCM have been proposed upon identification of autoantibodies (AABs) to cardiac antigens. However, their clinical and prognostic relevance still remain unclear. In this study, we evaluated the presence of circulating AABs against cardiac sarcomeric myosin (MHC) and troponin I (TnI) in the sera of PPCM patients and in relation to clinical presentation. In this case-control study, 70 patients diagnosed with PPCM and 50 pregnancy-matched healthy women with normal cardiac function were enrolled. Clinical assessment, echocardiography and blood tests were performed at baseline and at 6 ± 2 months follow-up. The presence of serum AABs against MHC (anti-MHC) and TnI (anti-TnI) was determined with a custom-made enzyme-linked immunosorbent assay (ELISA). The seropositivity for these AABs was correlated with the severity of LV dysfunction and the occurrence of pericardial effusion indicative of perimyocardial inflammation at baseline. Potential impact of these AABs on disease progression was evaluated with regard to functional (left ventricular ejection fraction) and clinical improvement at follow-up. Either anti-MHC or anti-TnI or both AABs were detected in the serum of 46 % of PPCM patients and in 8 % of healthy controls. In PPCM the presence of either one of these AABs was associated with significantly lower baseline LVEF and lower rate of full cardiac recovery at follow-up. Patients who were seropositive for anti-TnI AABs showed more frequently pericardial effusion indicative of a more pronounced immune response of the peri-/myocardium in these patients. Further studies are required to clarify cellular and molecular circuits leading to elevated levels of AABs and their pathophysiological relevance for disease initiation and progression in PPCM.

Low systolic blood pressure and high resting heart rate as predictors of outcome in patients with peripartum cardiomyopathy.

BACKGROUND: Patients with peripartum cardiomyopathy (PPCM) present with low blood pressure (SBP) often preventing uptitration of heart failure medication. We aimed to study prediction of risk and the contribution of high resting heart rate (HR) and low SBP to risk in recent onset of PPCM. METHODS: Clinical assessment with HR and SBP, echocardiography and laboratory results were obtained at baseline and at six months on 206 patients with recent onset PPCM enrolled at two tertiary care centers in South Africa. Poor outcome was defined as the combined endpoint of death, LVEF<35% or remaining in New York Heart Association (NYHA) functional class III/IV at six months. Complete LV recovery was defined as LVEF ≥ 55% at six months. RESULTS: Poor outcome was observed in 110 of 220 patients (53%), with 26 patients dying at six months (12.6%). There were 98 (47.5%) patients with SBP ≤ 110 mmHg. Patients with high HR (HR ≥ 100) and low SBP (< 110 mmHg) tended to have worse outcomes than patients below the HR median and high SBP. PPCM patients with low SBP and high HR were less likely to be on ACE-inhibitors (n = 35, 69% versus n = 129, 84%, p = 0.024) and on the beta blocker carvedilol (n = 24, 47% versus n = 98, 64%, p = 0.047). Low SBP, high HR and left ventricular end diastolic diameter at baseline were predictors of poor outcome. Patients with low SBP and high HR had the highest mortality (p = 0.0023). CONCLUSIONS: These findings suggest increased risk in patients with PPCM presenting with low SBP and high HR on standard heart failure medication possibly having implications on HF management.

Hypertension and hypertensive heart disease in African women.

Hypertension and hypertensive heart disease is one of the main contributors to a growing burden of non-communicable forms of cardiovascular disease around the globe. The recently published global burden of disease series showed a 33 % increase of hypertensive disorders in pregnancy in the past two decades with long-term consequences. Africans, particularly younger African women, appear to be bearing the brunt of this increasing public health problem. Hypertensive heart disease is particularly problematic in pregnancy and is an important contributor to maternal case-fatality. European physicians increasingly need to attend to patients from African decent and need to know about unique aspects of disease presentation and pharmacological as well as non-pharmacological care. Reductions in salt consumption, as well as timely detection and treatment of hypertension and hypertensive heart disease remain a priority for effective primary and secondary prevention of CVD (particularly stroke and CHF) in African women. This article reviews the pattern, potential causes and consequences and treatment of hypertension and hypertensive heart disease in African women, identifying the key challenges for effective primary and secondary prevention in this regard.

Inhibition of endothelial nitric oxide synthase induces and enhances myocardial fibrosis.

AIMS: The endothelial nitric oxide synthase (eNOS) contributes to cardiac remodelling. We studied the role of eNOS in the development of myocardial fibrosis during cardiac overload. METHODS AND RESULTS: Ten-week-old male C57/Bl6 wildtype (WT) and eNOS mice (eNOS(-/-)) were subjected to transverse aortic constriction (TAC, 360 µm) and WT were treated with L-N(G)-nitroarginine methyl ester (L-NAME, 100 mg/kg/day) for 35 days. Inhibition of eNOS by L-NAME induced interstitial fibrosis, augmented replacement fibrosis, and induced apoptosis of cardiac fibroblasts and cardiomyocytes. L-NAME and eNOS(-/-) markedly increased the fibrosis induced by TAC and enhanced the myocardial prevalence of CXCR4(pos) fibroblasts. Myocardial stromal-derived factor-1 (SDF-1) expression was up-regulated by l-NAME and down-regulated after TAC. Blood pressure lowering by co-treatment with hydralazine (250 mg/L/day) did not reverse the L-NAME effects. In mice transplanted with green fluorescent protein (GFP)(pos) bone marrow, L-NAME increased the percentage of GFP(pos) fibroblasts in the myocardium to 45-70%. Strain-mismatched BMT of eNOS(-/-)-BM increased and of WT-BM decreased the percentage of CXCR4(pos) fibroblasts in all groups. The number of fibrocytes (CD45(pos) collagen I(pos) cells) in the peripheral blood and in the bone marrow was increased both by TAC and L-NAME. L-NAME but not the inhibitor of inducible NOS 1400 W and of neuronal NOS 7-nitroindazole increased hydroxyproline and collagen Iα1. L-NAME up-regulated SDF-1 mRNA in cultured neonatal rat cardiac fibroblasts as well as their migratory capacity. CONCLUSION: eNOS inhibition induces and enhances cardiac fibrosis independently of blood pressure by activating SDF-1/CXCR4, extracellular matrix production in cardiac fibroblasts and by increasing recruitment of fibrocytes from the bone marrow.