0000000000451024
AUTHOR
Benjamin Lauzier
Carbon Monoxide Protects Against Ischemia-reperfusion Injury in Vitro via Antioxidant Properties
Carbon monoxide (CO) is believed to mediate many of the cytoprotective effects attributed to the activation of heme oxygenase (HO-1), the enzyme responsible for CO production. Recently, the study of CO-releasing molecules (CO-RMs) has provided a new approach for the delivery of CO. In the present study, we examined whether the cardioprotective properties of CO-RM2 in isolated rat hearts subjected to an ischemia-reperfusion (I/R) sequence were associated with the presence of CO. In addition, the antioxidant properties of CO-RM2 were evaluated. In hearts pretreated with CO-RM2, the improvement in contractile function at the end of the reperfusion period after 20 min of global total ischemia w…
0347: Beneficial cardiovascular effects of O-GlcNAc stimulation in early phase of septic shock
BackgroundO-GlcNAcylation, a post-translational modification, is the end product of the hexosamine biosynthetic pathway (HBP). Recent studies showed beneficial effects of its increase in acute pathologies, such as hemorrhagic shock. We postulated that increase in total protein OGlcNAcylation at the early phase of septic shock, a systemic inflammation associated with a cardiovascular dysfunction, could improve cardiovascular function and reduce mortality.MethodsTo induce an endotoxemic shock, rats (n=6-8) received iv either lipopolysaccharide (LPS, 5mg/kg) or saline (CTRL). After 1 h, fluid resuscitation (FR,15mL/kg of colloid, iv) was associated or not with HBP substrate: glucosamine (GlcN,…
In senescence accelerated mouse (SAM) heart, the protective effect of postconditioning is associated with a decrease in oxidative stress
Supplément vol.27, World Congress of Cardiology 2006; International audience; The senescent heart susceptibility to ischemia (I) triggers multiple processes especially oxidative stress but precise mechanisms remain unclear. New animal’s models such as "Senescence Accelerated Mouse" Prone 8 (SAM-P8) and their control (SAM-R1) can be useful for a better understanding of aging process. We studied heart adaptation of these mice to I/reperfusion (R) sequence and a putative cardioprotector effect of post-conditioning (PC). Isolated working mice (8 months) hearts were subjected to a global total ischemia (20 minutes at 38°C), followed by 40 minutes of reperfusion. 4 groups of hearts were constitut…
Protective Effects of a Discontinuous Treatment with Alpha-Lipoic Acid in Obesity-Related Heart Failure with Preserved Ejection Fraction, in Rats
Obesity induces hemodynamic and humoral changes that are associated with functional and structural cardiac remodeling, which ultimately result in the development of heart failure (HF) with preserved ejection fraction (HFpEF). In recent years, pharmacological studies in patients with HFpEF were mostly unsatisfactory. In these conditions, alternative new therapeutic approaches are necessary. The aim of our study was (1) to assess the effects of obesity on heart function in an experimental model and (2) to evaluate the efficacy of an alpha-lipoic acid (ALA) antioxidant treatment. Sprague-Dawley rats (7 weeks old) were either included in the control group (n = 6) or subjected to abdominal aorti…
Acute Administration of Epirubicin Induces Myocardial Depression in Isolated Rat Heart and Production of Radical Species Evaluated by Electron Spin Resonance Spectroscopy
The aim of our study was to evaluate the acute effect of epirubicin (EPI), an anthracycline anticancer drug, on the evolution of cardiac functional parameters and production of reactive oxygen/nitrogen species (RONS). Isolated perfused rat hearts were subjected to 70 minutes of EPI (10.3 microM) infusion and to 5 minutes of isoproterenol (ISO, 0.1 microM) at the end of the protocol. Coronary flow (CF), left ventricular developed pressure (LVDP), and lactate dehydrogenase (LDH) release in the coronary effluents were evaluated throughout the protocol. RONS were detected in the coronary effluents by electron spin resonance spectroscopy with a spin probe, 1-hydroxy-3-carboxy-pyrrolidine (CP-H, …
Anti-hypertensive effects of Rosuvastatin are associated with decreased inflammation and oxidative stress markers in hypertensive rats
International audience; Among their pleiotropic effects, statins exert antioxidant and anti-inflammatory properties. The aim of this study was to evaluate in normotensive (WKY) and in spontaneously hypertensive rats (SHR) the effect of rosuvastatin (ROSU) treatment on (1) plasma inflammation markers and endogenous NO synthase inhibitor (ADMA) levels, (2) reactive oxygen species (ROS) generated by circulating leukocytes and (3) vascular oxidative stress and tissue inflammation markers. Plasma cytokines were higher in SHR than in WKY, except for IL-4, which was lower in SHR than in WKY. SHR monocytes exhibited higher production of ROS than did WKY monocytes. In the experimental conditions, RO…
Increased oxidative stress is responsible for ether-lipid loss in the retina of senescence accelerated mouse (SAM)
International audience; Purpose: Ether–lipids represent an important class of retinal phospholipids but their exact functions are still unknown. They might act as antioxidants since the vinyl–ether double bond they contain could be the target for newly formed oxygenated radicals. In this work, we investigated the status of ether–lipids and aldehydes, their oxidative degradation products in the retina of a mouse model for aging, the senescence–accelerated mouse prone 8 (SAM P8), in which we reported a reduction of retinal function following 12 months of age (ARVO 2004 E–abstract 797). We completed this study by evaluating the oxidative stress in the retina. Methods: The quantification of eth…
Time course of asymmetric dimethylarginine (ADMA) and oxidative stress in fructose-hypertensive rats: A model related to metabolic syndrome
Asymmetric dimethylarginine (ADMA) is an endogenous modulator of endothelial function and oxidative stress, and increased levels of this molecule have been reported in some metabolic disorders and cardiovascular diseases. The aim of this work was to analyze the time course of dimethylarginine compounds and oxidative stress levels and the relationship between these and cardiovascular function in fructose-hypertensive rats.90 male Sprague-Dawley rats were randomized into 2 groups, fed for 3 months with standard (C) chow supplemented or not with fructose (F, 60%). After sacrifice at different weeks (W), the aorta and plasma were harvested to assess the vascular and biochemical parameters. Our …