Oxidative stress implication after prolonged storage donor heart with blood versus crystalloid cardioplegia and reperfusion versus static storage.

Several factors are known to limit cardiac transplantation, such as number of donors, quality of cardiac graft preservation, and ischemia-reperfusion injury. Some mechanisms of reperfusion injury are now recognized; they include oxygen free radical (OFR), white blood cells activation, changes in calcium influx, alteration of microvascular blood flow, and sympathetic activation. The goal of this study was to assess the effects of two types of cardioplegia with long-term storage, either static or continuous perfusion, in 30 isolated sheep hearts as a model for heart transplantation.

Oxidative stress implication in a new ex-vivo cardiac concordant xenotransplantation model.

Xenotransplantation (XT) reveals a growing interest for the treatment of cardiomyopathy. The major barrier is an acute vascular rejection due to an acute humoral rejection. This pathogenesis is a difficult issue and in order to elaborate means for its prevention, we analysed the implication of oxidative stress (OS) on hearts from mini-pigs followed by reperfusion with either autologous or human blood in an attempt to simulate xenotransplantation.

Activation of PAF receptor by oxidised LDL in human monocytes stimulates chemokine releases but not urokinase-type plasminogen activator expression.

Background: We investigated whether the increase of urokinase-type plasminogen activator (uPA) monocyte expression and chemokine releases induced by oxidised low density lipoproteins (LDL), which participate to vascular tissue remodeling and to atherosclerotic plaque rupture, involved proinflammatory phospholipid products having platelet-activating factor (PAF)-like activity via the PAF-receptor pathway.

Methods: uPA monocyte expression was stimulated by either copper ions-oxidised or O2*-/HO* free radical-oxidised LDL. The effects of PAF and oxidised LDL on the production of monocyte chemoattractant protein-1 and interleukin-8 were also examined.

A different approach to analyzing age-related HbA1c values in non-diabetic subjects.

Using appropriate statistical tests and taking into account the analytical performance of hemoglobin A1c (HbA1c) measurements, is it useful to establish HbA1c age-related values in non-diabetic subjects? Non-diabetic subjects (n=135, 72 women and 63 men) from the neuromuscular department of the Pitié-Salpétrière Hospital (Paris) were involved in our study. Subjects were divided into two groups related to age: 51 patients under 50 years old and 84 subjects aged 50 years or more. Fasting plasma glucose and HbA1c measurements were respectively performed by enzymatic assay using the hexokinase method and high-performance liquid chromatography based on the ion exchange methodology with high precision.

Protection of endogenous beta-carotene in LDL oxidized by oxygen free radicals in the presence of supraphysiological concentrations of melatonin.

This study was designed to evaluate the effect of high concentrations of melatonin on the peroxidation of human low density lipoproteins (LDLs) initiated by O(2)(*-) and ethanol-derived peroxyl radicals (RO(2)(*)) from water gamma radiolysis in the presence of ethanol. LDL (3 g/l; total LDL concentration) was oxidized in the absence of melatonin or in its presence at three concentrations (50 x 10(-6), 100 x 10(-6) or 250 x 10(-6) mol/l) in ethanol. Radiolytic yields (i.

Melatonin related compounds inhibit lipid peroxidation during copper or free radical-induced LDL oxidation.

This study was designed to evaluate the protective effect of two melatonin related compounds towards low density lipoproteins (LDL) oxidation initiated in vitro either by defined free radicals [i.e. superoxide anion (O2*-) and ethanol-derived peroxyl radicals (RO(2)(*))] produced by gamma radiolysis or by copper ions.

In vitro low-density lipoprotein oxidation by copper or *OH/O*(2)(-): new features on carbonylation and fragmentation of apolipoprotein B during the lag phase.

The aim of our study was to evaluate the carbonylation and the carbonylated fragmentation of apolipoprotein B upon low-density lipoprotein (LDL) oxidation induced in vitro by copper and *OH/O*(2)(-) free radicals generated by gamma-radiolysis. Therefore, we developed a very sensitive Western blot immunoassay using 2,4-dinitrophenylhydrazine which allows the revelation of the apolipoprotein B carbonylation and its carbonylated fragmentation. The main results of this study show that (i) apolipoprotein B carbonylation is present during the lag phase of LDL oxidation in the two oxidative processes and (ii) apolipoprotein B carbonylated fragmentation was not detected during the lag phase of copper-oxidized LDL but was detected during the propagation phase.