Déborah François

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Heat shock (HS) proteins (HSPs) induce protection against a number of stresses distinct from HS, including reactive oxygen species. In the human premonocytic line U937, we investigated in whole cells the effects of preexposure to HS and exposure to hydrogen peroxide (H2O2) on mitochondrial membrane potential, mass, and ultrastructure. HS prevented(More)
We recently identified protease nexin-1 (PN-1) or serpinE2, as a possibly underestimated player in maintaining angiogenic balance. Here, we used the well-characterized postnatal vascular development of newborn mouse retina to further investigate the role and the mechanism of action of PN-1 in physiological angiogenesis. The development of retinal(More)
We report severe coenzyme Q10 deficiency of muscle in a 4-year-old boy presenting with progressive muscle weakness, seizures, cerebellar syndrome, and a raised cerebro-spinal fluid lactate concentration. State-3 respiratory rates of muscle mitochondria with glutamate, pyruvate, palmitoylcarnitine, and succinate as respiratory substrates were markedly(More)
We report histochemical, immunocytochemical, biochemical and molecular studies of skeletal muscle from a 23-year-old man with Kearns-Sayre syndrome. Southern blot analysis revealed a 4.7 kb heteroplasmic deletion of the mitochondrial DNA mapping within genes coding for subunits of complexes I, IV and V of the respiratory chain and for tRNA. Cytochrome c(More)
Tobacco smoke (TS) has been implicated as a major risk factor in human pulmonary diseases including cancer. In this study, we used TS as a model of oxidative stress. TS-mediated oxidative stress has been shown to induce protein oxidation, DNA damage, and cell death. Here we investigated, in human and rodent cell lines, whether TS induces cell death by(More)
Genetic, biochemical and morphological investigations were conducted on skeletal muscle mitochondria from 6 cases of ocular myopathy: 4 cases with Kearns-Sayre syndrome (KSS) and 2 with chronic progressive external ophthalmoplegia. All of these 6 cases showed mitochondrial DNA (mtDNA) deletions in addition to normal sized DNA in the quadriceps muscle. The(More)
Smoking has been associated with a large number of diseases, in particular cancers. Among the many substances identified in tobacco smoke, reactive oxygen species (ROS) are major carcinogens. We have previously reported that exposure of mammalian cells to tobacco smoke induces the expression of stress proteins, as well as apoptosis (programmed cell death).(More)
BACKGROUND Protease nexin-1 (PN-1) is a serpin that inhibits plasminogen activators, plasmin, and thrombin. PN-1 is barely detectable in plasma, but we have shown recently that PN-1 is present within the α-granules of platelets. METHODS AND RESULTS In this study, the role of platelet PN-1 in fibrinolysis was investigated with the use of human platelets(More)
The free radicals nitric oxide (.NO) and superoxide (O(2)(-).) react to form peroxynitrite (ONOO(-)), a highly toxic oxidant species. In this study we investigated the respective effects of NO and ONOO(-) in monocytes from healthy human donors. Purified monocytes were incubated for 6 or 16 h with a pure NO donor (S-nitroso-N-acetyl-DL-penicillamine, 0-2(More)