Publications by authors named "Darrell Loeffler"

Aims: Circulating progenitor cells (CPCs) play a role in vascular repair and plaque stability, while osteocalcin (OC) expressing CPCs have been linked to unstable plaque and adverse cardiovascular outcomes. However, their role in cardiac allograft vasculopathy (CAV) has not been elucidated. This cohort study aimed to investigate the contribution of CPCs on CAV progression and cardiovascular events after heart transplantation.

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Osteogenic endothelial progenitor cells (EPCs) contribute to impaired endothelial repair and promote coronary artery disease (CAD) and vascular calcification. Immature EPCs expressing osteocalcin (OCN) has been linked to unstable CAD; however, phenotypic regulation of OCN-expressing EPCs is not understood. We hypothesized that gut-microbiome derived pro-inflammatory substance, trimethylamine N-oxide (TMAO) might be associated with mobilization of OCN-expressing EPCs.

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The aim of this study was to characterize endothelial progenitor cells with osteoblastic phenotype (EPC-OCNs) and their role in individuals with varying degrees of aortic stenosis (AS). Peripheral blood mononuclear cells retrieved from blood samples of individuals with mild (n=40), moderate (n=35), or severe (n=103) AS from September 16, 2008, through March 30, 2015, were analyzed by flow cytometry for the EPC surface markers CD34, CD133, and kinase insert domain receptor (KDR) and the osteoblastic cell surface marker OCN. Levels of EPC-OCNs were correlated with AS severity and calcifications.

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Background Soluble urokinase plasminogen activator receptor (su PAR ) is a proinflammatory biomarker associated with immune activation and fibrinolysis inhibition. Plasminogen activator inhibitor ( PAI -1) is associated with excessive fibrin accumulation, thrombus formation, and atherosclerosis. The relationship between cross-coronary su PAR and PAI -1 production and endothelial dysfunction remains unknown.

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Background: There is increasing evidence implying that the early and functionally highly active circulating endothelial progenitor cell (CEPC) phenotype (CD34-/CD133+/KDR+) with osteogenic potential (OCN+) might link between vascular atherosclerotic calcification and mechanisms of bone metabolism. We sought to evaluate the early OCN+ CEPC counts as an independent biomarker for the severity of coronary artery disease (CAD).

Methods: Peripheral blood samples were drawn from 593 patients undergoing clinically indicated coronary angiography.

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Objectives: This study tests the hypothesis that circulating mononuclear cells expressing osteocalcin (OCN) and bone alkaline phosphatase (BAP) are associated with distinct plaque tissue components in patients with early coronary atherosclerosis.

Background: Plaque characteristics implying vulnerability develop at the earliest stage of coronary atherosclerosis. Increasing evidence indicates that cells from the myeloid lineage might serve as important mediators of destabilization.

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Objectives: The purpose of this study was to determine the role of circulating endothelial progenitor cells with osteoblastic phenotype (EPC-OCN) in human aortic valve calcification (AVC).

Background: Recent evidence suggests that rather than passive mineralization, AVC is an active atherosclerotic process with an osteoblastic component resembling coronary calcification. We have recently identified circulating EPCs with osteogenic properties carrying both endothelial progenitor (CD34, KDR) and osteoblastic (osteocalcin [OCN]) cell surface markers.

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Article Synopsis
  • Vascular calcification is linked to diabetic vasculopathy, possibly involving endothelial progenitor cells (EPCs) that express osteocalcin (OCN).
  • The study aimed to investigate the connection between OCN-expressing cells and elevated glycated hemoglobin (HbA1c) levels in patients.
  • Results showed that individuals with higher HbA1c levels had significantly more OCN-positive cells, particularly a specific type of EPCs, indicating a potential role of these cells in vascular calcification during (pre-)diabetes.
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Aims: For the characterization of endothelial progenitor cells (EPCs), commonly the markers CD34 and KDR have been used. CD133+/CD34-/KDR+ cells may represent more immature 'early' progenitors. In patients with coronary artery disease (CAD), a large fraction of EPCs carry the osteoblastic marker osteocalcin (OCN), which may mediate vascular calcification and abnormal repair.

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Purpose: Cranberry juice (CJ) contains a remarkably high concentration of polyphenols, considered to be beneficial for cardiovascular and bone health. The current double-blind, randomized study was designed to test whether daily consumption of double-strength Ocean Spray light CJ (2 × 230 ml) over 4 months has beneficial effects on vascular function and on endothelial progenitor cells (EPCs) carrying the osteoblastic marker osteocalcin in particular.

Methods: A total of 84 participants (49.

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Aims: Endothelial progenitor cells (EPC) may participate in the repair of injured coronary endothelium. We have recently identified EPC co-expressing the osteoblastic marker osteocalcin [OCN (+) EPC] and found that their numbers are increased in patients with early and late coronary atherosclerosis. The current study was designed to test the hypothesis that early coronary atherosclerosis is associated with the retention of osteogenic EPC within the coronary circulation.

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