Search results for "Active oxygen"
showing 10 items of 884 documents
Importance of mitochondrial dynamin-related protein 1 in hypothalamic glucose sensitivity in rats.
2012
International audience; AIMS: Hypothalamic mitochondrial reactive oxygen species (mROS)-mediated signaling has been recently shown to be involved in the regulation of energy homeostasis. However, the upstream signals that control this mechanism have not yet been determined. Here, we hypothesize that glucose-induced mitochondrial fission plays a significant role in mROS-dependent hypothalamic glucose sensing. RESULTS: Glucose-triggered translocation of the fission protein dynamin-related protein 1 (DRP1) to mitochondria was first investigated in vivo in hypothalamus. Thus, we show that intracarotid glucose injection induces the recruitment of DRP1 to VMH mitochondria in vivo. Then, expressio…
Increased Oxidative Damage Associated with Unfavorable Cytogenetic Subgroups in Chronic Lymphocytic Leukemia
2014
Oxidative stress contributes to genomic instability in chronic lymphocytic leukemia (CLL), but its relationship with the acquisition of specific chromosomal abnormalities is unknown. We recruited 55 untreated CLL patients and assessed 8-oxo-2′-deoxyguanosine (8-oxo-dG), glutathione, and malondialdehyde (MDA) levels, and we compared them among the cytogenetic subgroups established using fluorescence in situ hybridization (FISH). Significant increases in 8-oxo-dG and/or MDA were observed in patients with unfavorable cytogenetic aberrations (17p and 11q deletions) compared to the 13q deletion group.TP53deletion patients exhibited a diminished DNA repair efficiency. Finally, cases with normal F…
Anti-inflammatory and antioxidant effects of muscarinic acetylcholine receptor (mAChR) activation in the rat hippocampus
2019
AbstractRecently we found that acute treatment with Oxotremorine (Oxo), a non-selective mAChRs agonist, up-regulates heat shock proteins and activates their transcription factor heat shock factor 1 in the rat hippocampus. Here we aimed to investigate: a) if acute treatment with Oxo may regulate pro-inflammatory or anti-inflammatory cytokines and oxidative stress in the rat hippocampus; b) if chronic restraint stress (CRS) induces inflammatory or oxidative alterations in the hippocampus and whether such alterations may be affected by chronic treatment with Oxo. In the acute experiment, rats were injected with single dose of Oxo (0.4 mg/kg) and sacrificed at 24 h, 48 h and 72 h. In the CRS ex…
Inflammation-Induced Alteration of Astrocyte Mitochondrial Dynamics Requires Autophagy for Mitochondrial Network Maintenance
2013
Accumulating evidence suggests that changes in the metabolic signature of astrocytes underlie their response to neuroinflammation, but how proinflammatory stimuli induce these changes is poorly understood. By monitoring astrocytes following acute cortical injury, we identified a differential and region-specific remodeling of their mitochondrial network: while astrocytes within the penumbra of the lesion undergo mitochondrial elongation, those located in the core-the area invaded by proinflammatory cells-experience transient mitochondrial fragmentation. In brain slices, proinflammatory stimuli reproduced localized changes in mitochondrial dynamics, favoring fission over fusion. This effect w…
Females Live Longer than Males: Role of Oxidative Stress
2011
One of the most significant achievements of the twentieth century is the increase in human lifespan. In any period studied, females live longer than males. We showed that mitochondrial oxidative stress is higher in males than females and that the higher levels of estrogens in females protect them against ageing, by up-regulating the expression of antioxidant, longevity-related genes. The chemical structure of estradiol confers antioxidant properties to the molecule. However, the low concentration of estrogens in females makes it unlikely that they exhibit significant antioxidant capacity in the organism. Therefore we studied the mechanisms enabling estradiol to be antioxidant at physiologic…
Part of the Series: From Dietary Antioxidants to Regulators in Cellular Signalling and Gene ExpressionRole of reactive oxygen species and (phyto)oest…
2006
There is increasing evidence that reactive oxygen species (ROS) are not only toxic but play an important role in cellular signalling and in the regulation of gene expression. We, here, discuss two examples of improved adaptive response to an altered cellular redox state. First, differences in longevity between males and females may be explained by a higher expression of antioxidant enzymes in females resulting in a lower yield of mitochondrial ROS. Oestrogens are made responsible for these phenomena. Oestradiol induces glutathione peroxidase-1 and MnSOD by processes requiring the cell surface oestrogen receptor (ER) and the activation of pathways usually involved in oxidative stress respons…
Preconditioning by Mitochondrial Reactive Oxygen Species Improves the Proangiogenic Potential of Adipose-Derived Cells-Based Therapy
2009
Objective— Transplantation of adipose-derived stroma cells (ADSCs) stimulates neovascularization after experimental ischemic injury. ADSC proangiogenic potential is likely mediated by their ability to differentiate into endothelial cells and produce a wide array of angiogenic and antiapoptotic factors. Mitochondrial reactive oxygen species (ROS) have been shown to control ADSC differentiation. We therefore hypothesized that mitochondrial ROS production may change the ADSC proangiogenic properties. Methods and Results— The use of pharmacological strategies (mitochondrial inhibitors, antimycin, and rotenone, with or without antioxidants) allowed us to specifically and precisely modulate mito…
Mitochondrial reactive oxygen species are obligatory signals for glucose-induced insulin secretion.
2009
OBJECTIVE—Insulin secretion involves complex events in which the mitochondria play a pivotal role in the generation of signals that couple glucose detection to insulin secretion. Studies on the mitochondrial generation of reactive oxygen species (ROS) generally focus on chronic nutrient exposure. Here, we investigate whether transient mitochondrial ROS production linked to glucose-induced increased respiration might act as a signal for monitoring insulin secretion. RESEARCH DESIGN AND METHODS—ROS production in response to glucose was investigated in freshly isolated rat islets. ROS effects were studied using a pharmacological approach and calcium imaging. RESULTS—Transient glucose increase …
TBC1D24-TLDc-related epilepsy exercise-induced dystonia: rescue by antioxidants in a disease model
2019
Genetic mutations in TBC1D24 have been associated with multiple phenotypes, with epilepsy being the main clinical manifestation. The TBC1D24 protein consists of the unique association of a Tre2/Bub2/Cdc16 (TBC) domain and a TBC/lysin motif domain/catalytic (TLDc) domain. More than 50 missense and loss-of-function mutations have been described and are spread over the entire protein. Through whole genome/exome sequencing we identified compound heterozygous mutations, R360H and G501R, within the TLDc domain, in an index family with a Rolandic epilepsy exercise-induced dystonia phenotype (http://omim.org/entry/608105). A 20-year long clinical follow-up revealed that epilepsy was self-limited in…
Antiatherosclerotic Effects of Small-Molecular-Weight Compounds Enhancing Endothelial Nitric-Oxide Synthase (eNOS) Expression and Preventing eNOS Unc…
2008
Many cardiovascular diseases are associated with reduced levels of bioactive nitric oxide (NO) and an uncoupling of oxygen reduction from NO synthesis in endothelial NO synthase (eNOS uncoupling). In human endothelial EA.hy 926 cells, two small-molecular-weight compounds with related structures, 4-fluoro-N-indan-2-yl-benzamide (CAS no. 291756-32-6; empirical formula C16H14FNO; AVE9488) and 2,2-difluoro-benzo[1,3]dioxole-5-carboxylic acid indan-2-ylamide (CAS no. 450348-85-3; empirical formula C17H13F2NO3; AVE3085), enhanced eNOS promoter activity in a concentration-dependent manner; with the responsible cis-element localized within the proximal 263 base pairs of the promoter region. RNA int…