Biomedical subjects

Oswald F Wagner

Publications and source records attributed to Oswald F Wagner.

4 recordsLinked to original sources

PubMed2003

Levels of adhesion molecules do not decrease after 3 months of statin therapy in moderate hypercholesterolaemia.

Studies in animals and humans indicate a pivotal role for adhesion molecules (AMs) in the pathogenesis of atherosclerosis. Whereas an association between hypercholesterolaemia and AM expression has been suggested, it is unclear whether lowering cholesterol decreases AM expression and release. We compared the effects of a 3-month treatment with standard doses of three different statins (atorvastatin, simvastatin and pravastatin) on plasma levels of circulating AM (cAM) in 75 hypercholesterolaemic patients in a randomized clinical trial. Plasma levels of circulating (c)E-selectin, circulating intercellular adhesion molecule-1 (cICAM-1) and circulating vascular cell adhesion molecule-1 (cVCAM-1) were measured before and after 3 months of therapy. None of the statins lowered plasma cAM levels and pooled analyses of all patients showed a 1.7% [95% confidence interval (CI), -1.4-4.9%] increase in cE-selectin, a 2.1% (95% CI, -0.2-4.4%) increase in cICAM-1, and a 2.7% (95% CI, -0.6-6.1%) increase in cVCAM-1 levels. cAM levels did not decrease, even in patients with a >50% decrease ( n =19) in low-density lipoprotein cholesterol levels. This study provides strong evidence that 3 months of therapy with three different statins does not decrease cAM levels, despite normalization of cholesterol levels, and a minor decrease in C-reactive protein levels in patients with moderate hypercholesterolaemia.

Adult↗

PubMed2003

Endotoxaemia modulates Toll-like receptors on leucocytes in humans.

The modulation of Toll-like receptors (TLR) 1, 2 and 4 was studied during experimental human endotoxaemia. Healthy volunteers received 2 ng/kg of lipopolysaccharide (LPS) endotoxin (n = 10). TLR1, 2 and 4 expression occurred on monocytes and neutrophils, with monocytes expressing higher baseline levels of TLR2. LPS infusion downmodulated TLR4 expression on neutrophils, with maximal downregulation occurring at 24 h (-62% from baseline; P < 0.03 versus baseline). Monocyte TLRs were upregulated in vivo (TLR1 and 2), and in vitro (TLR1, 2 and 4) 8 h after LPS bolus (P < 0.05 versus baseline). Therefore, neutrophils and monocytes differentially express surface TLRs, and endotoxaemia differentially regulates TLR expression.

Adult↗

PubMed2003

Enalapril does not alter adhesion molecule levels in human endotoxemia.

The angiotensin-converting enzyme inhibitor (ACE-I) enalapril has been shown to lower elevated levels of circulating adhesion molecules (cAM) in critically ill patients. To delineate the mechanisms of this possibly beneficial effect of enalapril, we studied the acute effects of enalapril in a well-defined model of endotoxin-triggered, cytokine-mediated cAM up-regulation. In a randomized, controlled trial, 30 healthy male volunteers received 2 ng/kg lipopolysaccharide (LPS) after pretreatment with placebo or 20 mg/day enalapril for 5 days or with a single dose of 20 mg of enalapril 2 h before LPS infusion. LPS infusion increased TNF levels 300-fold above normal, circulating (c) E-selectin levels by 425% (CI, 359%-492%), and P-selectin, VCAM-1, ICAM-1, and von Willebrand factor levels by 47%-74%. LPS infusion also enhanced ICAM-1 and CD11b expression 2- to 3-fold on monocytes. However, no differences were seen between treatment groups (P > 0.05), despite 95% inhibition of ACE activity by enalapril. Inhibition of ACE activity by enalapril does not influence plasma indices of endothelial activation after endotoxin infusion in healthy individuals. Our results do not support the concept of a beneficial clinical effect of enalaprilat in septicemia.

Adult↗

PubMed2003

Increased plasma levels of plasminogen activator inhibitor-1 and soluble vascular cell adhesion molecule after triacylglycerol infusion in man.

Increased plasma plasminogen activator inhibitor-1 (PAI-1) has been implicated in the development of vascular disease. In type 2 diabetes mellitus high PAI-1 levels are associated with increased plasma concentrations of free fatty acids (FFA) and triacylglycerol indicating an association or a causal relationship. To answer that question, the effect of FFA/triacylglycerol on plasma PAI-1 was examined. Ten healthy male volunteers were studied for 6 h during infusion of triacylglycerol [1.5 ml/min]/heparin [0.2 IU/(kg.min)] (LIP; n=10), saline only (SAL; n=10), and saline/heparin (HEP; n=5). Plasma insulin concentrations were kept constant at approximately 35 pmol/l by intravenous somatostatin-insulin infusions and there was no significant change in plasma glucose levels during any of the study protocols. LIP increased plasma triacylglycerol and FFA approximately 3- (p < 0.001) and approximately 8- (p < 0.000001) fold, respectively, within 90 min. Baseline plasma PAI-1 measured by a bio-immunoassay was similar in HEP (11.4 +/- 2.8 ng/ml), SAL (16.6 +/- 3.6 ng/ml), and LIP studies (15.2 +/- 3.4 ng/ml). Since studies were initiated in the morning, PAI-1 decreased (p < 0.025) over time following its normal diurnal variation to 6.4 +/- 2.0 ng/ml and 4.0 +/- 2.4 ng/ml at 360 min in SAL and HEP, respectively. During LIP, however, PAI-1 increased to approximately 2.6 fold higher levels than during SAL at 360 min (16.4 +/- 4.0 ng/ml, p < 0.01). While tissue plasminogen activator (tPA) and adipsin, an adipocyte derived protease, were unaffected by LIP, changes in soluble vascular cell adhesion molecule-1 (sVCAM-1) were significantly correlated (p = 0.02) with those seen for PAI-1. This suggests that hyperlipidemia independent of insulin and plasma glucose levels stimulates vascular tissue and in turn might induce an increase in plasma PAI-1. PAI-1 then could contribute to the development of atherothrombotic vascular disease.

Adult↗