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Johann Bauersachs

Publications and source records attributed to Johann Bauersachs.

At least 19 recordsLinked to original sources
PubMed2026

Recurrence of peripartum cardiomyopathy in subsequent pregnancy stratified by left ventricular function: a systematic review and meta-analysis.

AIMS: Subsequent pregnancy in women with prior peripartum cardiomyopathy (PPCM) carries a risk of relapse and adverse maternal outcomes. This meta-analysis aimed to determine the recurrence of PPCM relapse and associated maternal and foetal outcomes during subsequent pregnancy, stratified by baseline (pre-subsequent pregnancy) left ventricular ejection fraction (LVEF). METHODS: A systematic review and meta-analysis was conducted in accordance with PRISMA guidelines. Nine databases were searched through June 2025 for cohort studies reporting subsequent pregnancy outcomes in women with prior PPCM, stratified as recovered (LVEF &#x2265;50%) or non-recovered (LVEF <50%) groups. Outcomes included PPCM relapse, maternal mortality, LVEF during and after pregnancy, LV recovery, symptom worsening, and obstetric/neonatal events. Risk of bias was assessed with ROBINS-E, and random-effects models were used. RESULTS: Six cohort studies comprising 266 women were included (174 in recovered group and 92 in non-recovered group). Relapse occurred in both groups with no significant difference [rate ratio (RR) 0.77, 95% CI 0.50-1.19; I2 = 3%]. Maternal mortality was significantly lower in the recovered group (1.7% vs 10.9%; RR 0.27, 95% CI 0.09-0.87; I2 = 0%). Recovered group had higher mean LVEF during subsequent pregnancy (mean difference [MD] 17.0; P < .001), higher postpartum LVEF (MD 11.69; P = .005; I2 = 84%), and greater likelihood of LV recovery (RR 2.07; P = .005; I2 = 0%). No significant differences were observed in symptom worsening or obstetric/neonatal outcomes. CONCLUSION: Recovered LVEF prior to subsequent pregnancy is associated with improved maternal outcomes, yet relapse remains common. Left ventricular ejection fraction alone is insufficient for risk stratification, and individualized multidisciplinary care is essential for all women with prior PPCM.

Female↗
PubMed2025

Finerenone and Atrial Fibrillation in Heart Failure: A Secondary Analysis of the FINEARTS-HF Randomized Clinical Trial.

IMPORTANCE: Heart failure (HF) with mildly reduced or preserved ejection fraction and atrial fibrillation (AF) are closely intertwined. OBJECTIVE: To examine the efficacy and safety of the nonsteroidal mineralocorticoid receptor antagonist finerenone in patients with HF with mildly reduced or preserved ejection fraction according to the absence or presence of AF and the type of AF (paroxysmal vs persistent or permanent). DESIGN, SETTING, AND PARTICIPANTS: Prespecified analyses were conducted in the Finerenone Trial to Investigate Efficacy and Safety Superior to Placebo in Patients With Heart Failure (FINEARTS-HF) randomized clinical trial. The trial was conducted across 653 sites in 37 countries. Participants were adults aged 40 years and older with symptomatic HF and left ventricular ejection fraction of 40% or greater, randomized between September 2020 and January 2023. Data analysis was conducted from September 1 to October 1, 2024. INTERVENTION: Finerenone (titrated to 20 mg or 40 mg) or placebo. MAIN OUTCOMES AND MEASURES: The primary outcome was the composite of total HF events and cardiovascular death. New-onset AF or atrial flutter (AFL) was a prespecified exploratory outcome. RESULTS: Among 5984 patients (mean [SD] age, 72.0 [9.6] years; 2724 [45.5%] female) with known AF status at baseline, 1384 (23.1%) had paroxysmal AF and 1886 (31.5%) had persistent or permanent AF. Patients with both types of AF were older and had worse HF status compared with those without AF (2714 patients [45.4%]). Both types of AF were associated with a higher unadjusted risk of the primary outcome compared with no AF (event rate per 100 person-years of follow-up, 20.3 [95% CI, 17.9-23.1] with paroxysmal AF, 19.8 [95% CI, 17.8-22.0] with persistent or permanent AF, and 11.9 [95% CI, 10.7-13.3] with no AF; rate ratio [RR], 1.62 [95% CI, 1.37-1.92] with paroxysmal AF and 1.66 [95% CI, 1.43-1.93] with persistent or permanent AF vs no AF); however, the associations were attenuated after adjustment for known prognostic variables. The benefit of finerenone on the primary outcome (overall RR, 0.84 [95% CI, 0.74-0.95]) was not modified by baseline AF status (RR, 0.80 [95% CI, 0.65-0.98] with no AF, 0.83 [95% CI, 0.65-1.06] with paroxysmal AF, and 0.85 [95% CI, 0.69-1.05] with persistent or permanent AF; P for interaction&#x2009;=&#x2009;.94). New-onset AF or AFL occurred in 6.5% of patients and was associated with a higher subsequent adjusted risk of the primary outcome (rate ratio, 3.65 [95% CI, 2.57-5.18]; P&#x2009;<&#x2009;.001). The subdistribution hazard ratio for new-onset AF or AFL among those receiving finerenone vs placebo was 0.77 (95% CI, 0.57-1.04; P&#x2009;=&#x2009;.09). CONCLUSIONS AND RELEVANCE: The efficacy of finerenone was consistent regardless of AF status. New-onset AF was associated with a substantially higher risk of subsequent outcomes. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT04435626.

Humans↗
PubMed2006

The CX3C chemokine fractalkine induces vascular dysfunction by generation of superoxide anions.

OBJECTIVE: The chemokine fractalkine activates platelets and induces leukocyte adhesion to the endothelium. Expression of fractalkine and its receptor, CX3CR1, is elevated in coronary artery disease. We assessed the effects of fractalkine on vascular function in isolated rat aorta. METHODS AND RESULTS: CX3CR1 expression was demonstrated in rat aortic endothelial and smooth muscle cells by immunohistochemistry, Western blot, and polymerase chain reaction (PCR). Fractalkine (up to 1 microg/mL) did not directly induce contractile or relaxant responses when applied to rat aortic rings in organ baths. Short-term incubation with fractalkine (1 microg/mL) for 5 minutes did not affect vascular reactivity. Pretreatment of isolated rat aortic rings with fractalkine for 2 hours impaired acetylcholine-induced nitric oxide (NO)-mediated relaxation after preconstriction with phenylephrine in a concentration-dependent manner. The concentration response to the NO donor DEA-NONOate was significantly shifted to the right. The radical scavenger tiron normalized the attenuated acetylcholine-induced relaxation after fractalkine incubation. Aortic superoxide formation was enhanced by fractalkine, which was inhibited by diphenyleneiodonium but not by inhibitors of xanthine oxidase or NO synthase. CONCLUSIONS: In addition to its role as a chemokine and adhesion molecule, fractalkine induces vascular dysfunction by stimulating vascular reactive oxygen species resulting in reduced NO bioavailability.

Acetylcholine↗
PubMed2006

Soluble guanylyl cyclase activation with HMR1766 attenuates platelet activation in diabetic rats.

OBJECTIVE: Platelet activation significantly contributes to cardiovascular morbidity and mortality in diabetes. An association between impaired NO-mediated platelet inhibition and platelet activation has recently been demonstrated in experimental diabetes. Guanylyl cyclase activation enhances the reduced signaling via the NO/cGMP pathway. We investigated whether chronic guanylyl cyclase activation would beneficially modulate platelet activation in experimental diabetes mellitus. METHODS AND RESULTS: Diabetes was induced by streptozotocin-injection in male Wistar rats. After 2 weeks, treatment with either placebo or the guanylyl cyclase activator HMR1766 (10 mg/kg twice daily by gavage) was initiated. Two weeks later, in vivo platelet activation and in vitro platelet reactivity were assessed. Chronic treatment with HMR1766 enhanced NO/cGMP-mediated signaling in platelets from diabetic rats determined by in vivo phosphorylation of platelet vasodilator-stimulated phosphoprotein (VASP) at Ser157 and Ser239. In parallel, platelet-binding of fibrinogen, surface-expression of P-selectin, appearance of platelet-derived microparticles, and platelet-aggregates with other blood cells were significantly reduced by chronic treatment with HMR1766. CONCLUSIONS: Chronic activation of soluble guanylyl cyclase in diabetic rats improved markers of platelet activation and is a rationale approach for prevention of adverse cardiovascular events in diabetes.

Animals↗
PubMed2006

Accurate quantification of dimethylamine (DMA) in human urine by gas chromatography-mass spectrometry as pentafluorobenzamide derivative: evaluation of the relationship between DMA and its precursor asymmetric dimethylarginine (ADMA) in health and disease.

Dimethylamine [DMA, (CH(3))(2)NH)] is abundantly present in human urine. Main sources of urinary DMA have been reported to include trimethylamine N-oxide, a common food component, and asymmetric dimethylarginine (ADMA), an endogenous inhibitor of nitric oxide (NO) synthesis. ADMA is excreted in the urine in part unmetabolized and in part after hydrolysis to DMA by dimethylarginine dimethylaminohydrolase (DDAH). Here we describe a GC-MS method for the accurate and rapid quantification of DMA in human urine. The method involves use of (CD(3))(2)NH as internal standard, simultaneous derivatization with pentafluorobenzoyl chloride and extraction in toluene, and selected-ion monitoring of m/z 239 for DMA and m/z 245 for (CD(3))(2)NH in the electron ionization mode. GC-MS analysis of urine samples from 10 healthy volunteers revealed a DMA concentration of 264+/-173 microM equivalent to 10.1+/-1.64 micromol/mmol creatinine. GC-tandem MS analysis of the same urine samples revealed an ADMA concentration of 27.3+/-15.3 microM corresponding to 1.35+/-1.2 micromol/mmol creatinine. In these volunteers, a positive correlation (R=0.83919, P=0.0024) was found between urinary DMA and ADMA, with the DMA/ADMA molar ratio being 10.8+/-6.2. Elevated excretion rates of DMA (52.9+/-18.5 micromol/mmol creatinine) and ADMA (3.85+/-1.65 micromol/mmol creatinine) were found by the method in 49 patients suffering from coronary artery disease, with the DMA/ADMA molar ratio also being elevated (16.8+/-12.8). In 12 patients suffering from end-stage liver disease, excretion rates of DMA (47.8+/-19.7 micromol/mmol creatinine) and ADMA (5.6+/-1.5 micromol/mmol creatinine) were found to be elevated, with the DMA/ADMA molar ratio (9.17+/-4.2) being insignificantly lower (P=0.46). Between urinary DMA and ADMA there was a positive correlation (R=0.6655, P<0.0001) in coronary artery disease, but no correlation (R=0.27339) was found in end-stage liver disease.

Acetazolamide↗
PubMed2006

Medroxyprogesterone acetate but not drospirenone ablates the protective function of 17 beta-estradiol in aldosterone salt-treated rats.

Controversial results obtained from human and animal studies on the prevention of heart disease by estrogens and progestins warrant a better understanding of nuclear hormone receptor function and interaction. To address this issue and taking into account that effects of synthetic progestins are not only referable to action through the progesterone receptor but may also be mediated by other steroid receptors, we characterized cardiovascular function and inflammatory gene expression in aldosterone salt-treated rats on long-term administration of 17beta-estradiol, medroxyprogesterone acetate, and drospirenone, a new progestogen exhibiting antimineralocorticoid activity. The complex pattern of cardiovascular injury in ovariectomized Wistar rats induced by chronic aldosterone infusion plus a high-salt diet was significantly attenuated in sham-ovariectomized rats and by coadministration of 17beta-estradiol in ovariectomized animals after 8 weeks of continuous treatment. The beneficial role of 17beta-estradiol on blood pressure, cardiac hypertrophy, vascular osteopontin expression, perivascular fibrosis, and impaired NO-dependent relaxation of isolated aortic rings was completely abrogated by coadministration of medroxyprogesterone acetate. In contrast, drospirenone was either neutral or additive to 17beta-estradiol in protecting against aldosterone salt-induced cardiovascular injury and inflammation. The current results support the hypothesis of complex interactions among estrogen, progesterone, glucocorticoid, androgen, and mineralocorticoid receptor signaling in cardiovascular injury and inflammation. Novel progestins, such as drospirenone, confer superior effects compared with medroxyprogesterone acetate in a model of aldosterone-induced heart disease because of its antimineralocorticoid properties.

Aldosterone↗
PubMed2006

Simvastatin improves left ventricular function after myocardial infarction in hypercholesterolemic rabbits by anti-inflammatory effects.

OBJECTIVES: Hypercholesterolemia contributes to coronary artery disease progression but little is known about its effect on left ventricular (LV) function after myocardial infarction (MI). The aim of this study was to investigate the effects of hypercholesterolemia and statin treatment in rabbits with experimental MI. METHODS AND RESULTS: New Zealand White rabbits on a normal or cholesterol-rich diet for 4 weeks, underwent permanent coronary artery ligation. Starting on the first day post-MI rabbits were treated with either placebo or simvastatin (5 mg/kg/day) for 9 weeks. Hypercholesterolemia itself did not affect LV function in sham-operated animals but further impaired LV systolic (dP/dtmax -42%) and diastolic (dP/dtmin -47%) function in MI rabbits on placebo. Simvastatin treatment not only prevented deterioration of LV function associated with hypercholesterolemia but improved LV function (dP/dtmax +130%; dP/dtmin +144%, P < 0.05). Simvastatin also attenuated the depression of LV function in normocholesterolemic MI rabbits (dP/dtmax +46%; dP/dtmin +53%, P < 0.05). Hypercholesterolemia in MI rabbits coincided with a significant increase in C-reactive protein levels (marker of inflammation) and Rac1-GTPase activity (marker of oxidative stress), and a reduction in cardiac sarcoplasmic-reticulum calcium ATPase-2 expression and endothelial nitric oxide synthase protein phosphorylation, all of which were normalised by simvastatin treatment. Elevated serum cholesterol levels were only partially reduced by simvastatin. CONCLUSIONS: Hypercholesterolemia further impaired the depressed LV function in rabbits post-MI. Statin treatment reversed this effect, and conferred additional protection, as in normocholesterolemic animals. Our study suggests that anti-inflammatory and anti-oxidative effects of simvastatin substantially contribute to its beneficial effects on cardiac function after MI.

Animals↗
PubMed2006

Microarray-based gene expression profiling to elucidate cellular responses to nitric oxide--a review from an analytical and biomedical point of view.

Nitric oxide (NO) produced by NO synthases (NOS) regulates a wide range of cellular functions. Analysis by gene arrays provides valuable information for identifying important elements of the cellular responses to NO. Such screening tools might be useful to elucidate NO-responsive regulators, which play a central role in mediating NO effects. Although the final importance of a particular gene is determined by the encoded protein and further protein modifications, measurements of RNA levels have proven to be partly valuable in identifying the molecular changes that occur in cells. Microarray technology permits large-scale and genome-wide analysis of gene expression from multiple samples. We review the current knowledge of the use of microarray gene expression screening in elucidating the effects of NO on various cells and tissues. We also point out the limitations of general microarray-based gene expression analyses and especially when investigating the effects of NO.

Animals↗
PubMed2006

Absence of NF-kappaB subunit p50 improves heart failure after myocardial infarction.

BACKGROUND: NF kappa B (NF-kappaB) is a ubiquitous transcription factor activated by various stimuli implicated in heart failure progression including reactive oxygen species (ROS), hypoxia, and inflammatory cytokines. Although NF-kappaB is involved in ischemic preconditioning, unstable angina pectoris, and atherogenesis, its role in heart failure has not been determined. Therefore, we investigated left ventricular remodeling in mice with a targeted deletion of the NF-kappaB subunit p50/NF-kappaB1 after myocardial infarction. METHODS AND RESULTS: p50 knockout (KO) and wild-type (WT) animals underwent coronary artery ligation. Transthoracic echocardiography was performed at days 0, 21, and 56 at midpapillary levels. Early mortality was significantly lower in KO than in WT animals. Moreover, p50 KOs exhibited significantly reduced ventricular dilatation over 8 wk compared to WT controls (end-systolic diameters by transthoracic echocardiography, WT vs. KO, 0.55+/-0.04 vs. 0.34+/-0.03 cm) and preserved left ventricular contractility. Collagen content and matrixmetalloproteinase (MMP) -9 expression were significantly lower in KO mice after myocardial infarction and may account for improved left ventricular remodeling. CONCLUSIONS: Absence of the NF-kappaB subunit p50 improves early survival and reduces left ventricular dilatation after myocardial infarction. NF-kappaB might therefore be an attractive target to treat heart failure.

Animals↗
PubMed2006

[Aldosterone receptor blockade after acute myocardial infarction with heart failure].

BACKGROUND: Based on the RALES study, in patients with moderate to severe chronic heart failure and reduced left ventricular function, the nonselective aldosterone antagonist spironolactone has a well-established role in combination with ACE inhibition, beta-blockade and diuretics. This indication was recently reinforced by the guideline for chronic heart failure therapy of the German Cardiac Society, although there is no formal approval for spironolactone for this indication in Germany. NEW CLINICAL STUDIES: Heart failure after acute myocardial infarction represents a new indication for aldosterone receptor blockade. In the EPHESUS trial of patients with acute myocardial infarction, reduced ejection fraction, and clinical signs of heart failure, the selective aldosterone antagonist eplerenone in combination with ACE inhibition and beta-blockade significantly reduced mortality. The best benefit was achieved by early treatment, i. e., starting 3-7 days post myocardial infarction. In addition, as early as after 30 days, eplerenone-treated patients had significantly reduced mortality and hospitalization. Eplerenone was approved for the indication heart failure after acute myocardial infarction in late 2004 in Germany. PURPOSE OF THIS STUDY: The present review summarizes the pathophysiological basis, the experimental and clinical trials that constitute the rationale for therapy with aldosterone antagonists in patients with acute myocardial infarction and heart failure. Tips for use in clinical practice are given which allow to profit from the effective potential for mortality and morbidity reduction of aldosterone receptor blockade and to minimize the risk of serious hyperkalemia.

Adrenergic beta-Antagonists↗
PubMed2006

Apoptosis repressor with caspase recruitment domain is required for cardioprotection in response to biomechanical and ischemic stress.

BACKGROUND: Ischemic heart disease and heart failure are associated with an increased loss of cardiomyocytes due to apoptosis. Whether cardiomyocyte apoptosis plays a causal role in the pathogenesis of heart failure remains enigmatic. The apoptosis repressor with caspase recruitment domain (ARC) is a recently discovered antiapoptotic factor with a highly specific expression pattern in striated muscle and neurons. ARC is a master regulator of cardiac death signaling because it is the only known factor that specifically inhibits both the intrinsic and extrinsic apoptotic death pathway. In this study we attempted to elucidate the physiological role of ARC and to understand pathophysiological consequences resulting from its deletion. METHODS AND RESULTS: We generated ARC-deficient mice, which developed normally to adulthood and had no abnormality in cardiac morphology and function under resting conditions. On biomechanical stress induced by aortic banding, ARC-deficient mice developed accelerated cardiomyopathy compared with littermate controls, which was characterized by reduced contractile function, cardiac enlargement, and myocardial fibrosis. Likewise, ischemia/reperfusion injury of ARC-deficient mice resulted in markedly increased myocardial infarct sizes. Although in both instances a significant increase in apoptotic cardiomyocytes could be observed in ARC-deficient mice, neither in vitro nor in vivo studies revealed any effect of ARC on classic hypertrophic cardiomyocyte growth responses. The pathophysiological relevance of downregulated ARC levels was underscored by specimens from failing human hearts showing markedly reduced ARC protein levels. CONCLUSIONS: Our study identifies a tissue-specific antiapoptotic factor that is downregulated in human failing myocardium and that is required for cardioprotection in pressure overload and ischemia.

Animals↗
PubMed2006

Caught in the act: in vivo molecular imaging of the transcription factor NF-kappaB after myocardial infarction.

Nuclear factor kappaB (NF-kappaB) is a ubiquitous transcription factor activated by various stimuli implicated in heart failure progression. However, its activation in heart failure has not been well defined yet. Therefore, we investigated activation of NF-kappaB after myocardial infarction. For the first time, we performed serial, non-invasive in vivo molecular imaging of transcription factor activation in the heart. We used mice expressing a luciferase reporter whose transcription is dependent upon NF-kappaB activation for up to 8 weeks after myocardial infarction. There was a significant increase of NF-kappaB activity with a maximum at day 3 after myocardial infarction when compared to sham controls. Thus, in vivo measurement of the activation of NF-kappaB is feasible. NF-kappaB activity might play an important role for the remodeling process.

Animals↗
PubMed2006

Bone marrow molecular alterations after myocardial infarction: Impact on endothelial progenitor cells.

OBJECTIVE: Standard drugs post-myocardial infarction (MI) such as angiotensin converting enzyme (ACE) and 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase inhibitors (statins) increase levels of endothelial progenitor cells (EPC). However, potential underlying mechanisms have not yet been investigated. METHODS AND RESULTS: We studied the effects of ACE inhibition or statin treatment on EPC levels and on bone marrow molecular pathways involved in EPC mobilization after MI in rats. Three days post-infarction, acetylated LDL (acLDL)+/Ulex europeus-1 (UEA-1)+/VEGF receptor-2+/eNOS+ EPC levels and formation of endothelial colony forming units (CFU) were reduced to 60+/-12% (p < 0.05) and 68+/-7% (p < 0.05). In bone marrow, extracellular signal-regulated kinase (ERK) phosphorylation and matrix metalloproteinase (MMP)-9 activity were repressed. Endothelial nitric oxide synthase (eNOS) activity was unchanged, whereas reactive oxygen species (ROS) were increased two-fold in bone marrow. ACE or HMG-CoA reductase inhibition resulted in significant increases in EPC levels. ACE inhibition increased bone marrow ERK phosphorylation and MMP-9 activity. Statin therapy enhanced bone marrow VEGF protein levels, Akt phosphorylation, eNOS activity and normalized increased ROS levels. Augmented EPC levels in the early post-infarction phase by ACE inhibition or statin treatment were associated with improved cardiac function and increased capillary density in the peri-infarct area 7 days after MI. Moreover, increased EPC levels in response to ACE inhibition or statin treatment were sustained 10 weeks post-infarction. CONCLUSIONS: Increased ROS and impaired MMP-9 activity in bone marrow likely contribute to reduced EPC mobilization in the early post-infarction phase. ACE inhibition or statin treatment increased EPC levels with distinct drug-specific effects on bone marrow molecular alterations.

Angiotensin-Converting Enzyme Inhibitors↗
PubMed2005

Left ventricular remodeling after myocardial infarction in mice with targeted deletion of the NADPH oxidase subunit gp91PHOX.

BACKGROUND: Oxidative stress is involved in progression of left ventricular hypertrophy and heart failure. Since NADPH oxidases are a major source of reactive oxygen species in the heart, we studied left ventricular remodeling after myocardial infarction in mice with targeted deletion of the NADPH oxidase subunit gp91(phox). METHODS AND RESULTS: gp91(phox) knockout (KO) and wild-type (WT) animals underwent coronary artery ligation. Mortality was significant higher in the gp91(phox) KO mice. However, transthoracic echocardiography performed at days 1, 7, and 56 at mid-papillary levels revealed that progression of left ventricular remodeling was not influenced by the genotype. Moreover, systemic oxidative stress was not reduced in gp91(phox) KO mice as indicated by a significant increase in lipid peroxides potentially mediated by an increase of the NADPH subunit nox-1 in gp91(phox) KO mice. CONCLUSION: Targeted deletion of the NADPH subunit gp91(phox) does not affect left ventricular remodeling following myocardial infarction and does not decrease the production of oxidative stress. However, the final role of the different NADPH subunits in the heart under pathophysiologic conditions remains to be determined.

Animals↗
PubMed2005

The dying stem cell hypothesis: immune modulation as a novel mechanism for progenitor cell therapy in cardiac muscle.

Stem cell transplantation after myocardial infarction has been claimed to restore cardiac function, but the underlying mechanism remains unclear. A minority of transplanted cells become adherent in heart tissue and contribute to neovascularization, whereas many donor cells die from apoptosis. We propose that apoptosis of transplanted cells modulates local tissue reactions. Apoptotic cells impact on immune reactivity by down-regulating innate and adaptive immunity, deactivating macrophages and dendritic cells, and stimulating regulatory T cells. This leads to reduced scar formation, repressed myocardial apoptosis, and improved cardiac outcome.

Animals↗
PubMed2005

Suppression of endothelial progenitor cells in human coronary artery disease by the endogenous nitric oxide synthase inhibitor asymmetric dimethylarginine.

OBJECTIVES: We tested the hypothesis that asymmetric dimethylarginine (ADMA) may be an endogenous inhibitor of endothelial progenitor cells (EPCs). BACKGROUND: Endothelial progenitor cells play a pivotal role in regeneration of injured endothelium, thereby limiting the formation of atherosclerotic lesions. Reduced numbers of EPCs may affect progression of coronary artery disease. Regulation of EPC mobilization and function is mediated in part by nitric oxide (NO). Endogenous inhibitors of NO synthases, such as ADMA, contribute to endothelial dysfunction and injury. METHODS: We used flow cytometry and in vitro assays to investigate the relationship between EPC number and function with ADMA plasma levels in patients with stable angina. RESULTS: The plasma concentration of ADMA was related to the severity of coronary artery disease and correlated inversely with the number of circulating CD34+/CD133+ progenitor cells (r = -0.69; p < 0.0001) and endothelial colony forming units (CFUs) (r = -0.75; p < 0.0001). Adjusting for all patient characteristics, we confirmed these findings in multivariate regression analyses. In vitro differentiation of EPCs was repressed by ADMA in a concentration-dependent manner. Compared with untreated cells, ADMA reduced EPC incorporation into endothelial tube-like structures to 27 +/- 11% (p < 0.001). Asymmetric dimethylarginine repressed the formation of CFUs from cultured peripheral blood mononuclear cells to 35 +/- 7% (p < 0.001). Asymmetric dimethylarginine decreased endothelial nitric oxide synthase activity in EPCs to 64 +/- 6% (p < 0.05) when compared with controls. Co-incubation with the hydroxymethyl glutaryl coenzyme A reductase inhibitor rosuvastatin abolished the detrimental effects of ADMA. CONCLUSIONS: Asymmetric dimethylarginine is an endogenous inhibitor of mobilization, differentiation, and function of EPCs. This contributes to the cardiovascular risk in patients with high ADMA levels and may explain low numbers and function of EPCs in patients with coronary artery disease.

Arginine↗