Search results for "SUPEROXIDE DISMUTASE"
showing 10 items of 296 documents
Tissue antioxidant status differs in spontaneously hypertensive rats fed fish protein or casein
2003
The present study was designed to determine whether changes in dietary protein source are related to changes in antioxidant status determined by enzyme activities of catalase, superoxide dismutase (SOD), gluthatione peroxidase (GSH-Px) and gluthatione reductase (GSSG-Red) and lipid peroxidation levels in various tissues. Spontaneously hypertensive rats (SHR; 5 wk old) were fed diets containing 20% casein or fish protein for 2 mo. Feeding the fish protein diet lowered blood pressure and reduced plasma total cholesterol levels and SOD activity in all tissues except muscle compared with the casein diet. Feeding fish protein also enhanced GSH level and GSH-Px activity in liver and heart, accomp…
Role of mitochondrial oxidative stress to explain the different longevity between genders. Protective effect of estrogens
2006
Females live longer than males. Work from our laboratory has shown that this may be due to the up-regulation of longevity-associated genes by estrogens. Estrogens bind to the estrogen receptors and subsequently activate the mitogen activated protein kinase and nuclear factor kappa B signalling pathways, resulting in an up-regulation of antioxidant enzymes. Estrogen administration, however, has serious undesirable effects and of course, cannot be administered to males because of its powerful feminizing effects. Thus, we tested the effect of genistein, a phytoestrogen of high nutritional importance whose structure is similar to estradiol, on the regulation of the expression of antioxidant, lo…
Abnormalities of mitochondrial functioning can partly explain the metabolic disorders encountered in sarcopenic gastrocnemius.
2007
International audience; Aging triggers several abnormalities in muscle glycolytic fibers including increased proteolysis, reactive oxygen species (ROS) production and apoptosis. Since the mitochondria are the main site of substrate oxidation, ROS production and programmed cell death, we tried to know whether the cellular disorders encountered in sarcopenia are due to abnormal mitochondrial functioning. Gastrocnemius mitochondria were extracted from adult (6 months) and aged (21 months) male Wistar rats. Respiration parameters, opening of the permeability transition pore and ROS production, with either glutamate (amino acid metabolism) or pyruvate (glucose metabolism) as a respiration substr…
Response of human endothelial cells to oxidative stress on Ti6Al4V alloy.
2007
Titanium and its alloys are amongst the most frequently used materials in bone and dental implantology. The good biocompatibility of titanium(-alloys) is attributed to the formation of a titanium oxide layer on the implant surface. However, implant failures do occur and this appears to be due to titanium corrosion. Thus, cells participating in the wound healing processes around an implanted material, among them endothelial cells, might be subjected to reactive oxygen species (ROS) formed by electrochemical processes during titanium corrosion. Therefore, we studied the response of endothelial cells grown on Ti6Al4V alloy to H(2)O(2) and compared this with the response of endothelial cells gr…
Anti-proliferative and pro-apoptotic activities of hydroxytyrosol on different tumour cells: the role of extracellular production of hydrogen peroxide
2011
Several recently published data suggest that the anti-proliferative and pro-apoptotic properties of hydroxytyrosol [3,4-dihydroxyphenyl ethanol (3,4-DHPEA)] on HL60 cells may be mediated by the accumulation of hydrogen peroxide (H2O2) in the culture medium. The aim of this study was to clarify the role played by H2O2 in the chemopreventive activities of 3,4-DHPEA on breast (MDA and MCF-7), prostate (LNCap and PC3) and colon (SW480 and HCT116) cancer cell lines and to investigate the effects of cell culture medium components and the possible mechanisms at the basis of the H2O2-producing properties of 3,4-DHPEA. The proliferation was measured by the MTT assay and the apoptosis by both fluores…
Mitochondrial dynamics in type 2 diabetes: Pathophysiological implications
2017
Mitochondria play a key role in maintaining cellular metabolic homeostasis. These organelles have a high plasticity and are involved in dynamic processes such as mitochondrial fusion and fission, mitophagy and mitochondrial biogenesis. Type 2 diabetes is characterised by mitochondrial dysfunction, high production of reactive oxygen species (ROS) and low levels of ATP. Mitochondrial fusion is modulated by different proteins, including mitofusin-1 (MFN1), mitofusin-2 (MFN2) and optic atrophy (OPA-1), while fission is controlled by mitochondrial fission 1 (FIS1), dynamin-related protein 1 (DRP1) and mitochondrial fission factor (MFF). PARKIN and (PTEN)-induced putative kinase 1 (PINK1) partici…
Genes, Ageing and Longevity in Humans: Problems, Advantages and Perspectives.
2006
Many epidemiological data indicate the presence of a strong familial component of longevity that is largely determined by genetics, and a number of possible associations between longevity and allelic variants of genes have been described. A breakthrough strategy to get insight into the genetics of longevity is the study of centenarians, the best example of successful ageing. We review the main results regarding nuclear genes as well as the mitochondrial genome, focusing on the investigations performed on Italian centenarians, compared to those from other countries. These studies produced interesting results on many putative "longevity genes". Nevertheless, many discrepancies are reported, l…
Heterozygous deficiency of manganese superoxide dismutase in mice (Mn-SOD+/-): a novel approach to assess the role of oxidative stress for the develo…
2005
Nitroglycerin (GTN)-induced tolerance was reported to be associated with increased levels of reactive oxygen species (ROS) in mitochondria. In the present study, we further investigated the role of ROS for the development of nitrate tolerance by using heterozygous manganese superoxide dismutase knock-out mice (Mn-SOD+/-). Mn-SOD is acknowledged as a major sink for mitochondrial superoxide. Vasodilator potency of mouse aorta in response to acetylcholine and GTN was assessed by isometric tension studies. Mitochondrial ROS formation was detected by 8-amino-5-chloro-7-phenylpyrido[3,4-d]pyridazine-1,4-(2H,3H)dione sodium salt (L-012)-enhanced chemiluminescence and mitochondrial aldehyde dehydro…
Manganese superoxide dismutase and aldehyde dehydrogenase deficiency increase mitochondrial oxidative stress and aggravate age-dependent vascular dys…
2008
AimsImbalance between pro- and antioxidant species (e.g. during aging) plays a crucial role for vascular function and is associated with oxidative gene regulation and modification. Vascular aging is associated with progressive deterioration of vascular homeostasis leading to reduced relaxation, hypertrophy, and a higher risk of thrombotic events. These effects can be explained by a reduction in free bioavailable nitric oxide that is inactivated by an age-dependent increase in superoxide formation. In the present study, mitochondria as a source of reactive oxygen species (ROS) and the contribution of manganese superoxide dismutase (MnSOD, SOD-2) and aldehyde dehydrogenase (ALDH-2) were inves…
Mitochondrial oxidative stress and nitrate tolerance – comparison of nitroglycerin and pentaerithrityl tetranitrate in Mn-SOD+/- mice
2006
Abstract Background Chronic therapy with nitroglycerin (GTN) results in a rapid development of nitrate tolerance which is associated with an increased production of reactive oxygen species (ROS). According to recent studies, mitochondrial ROS formation and oxidative inactivation of the organic nitrate bioactivating enzyme mitochondrial aldehyde dehydrogenase (ALDH-2) play an important role for the development of nitrate and cross-tolerance. Methods Tolerance was induced by infusion of wild type (WT) and heterozygous manganese superoxide dismutase mice (Mn-SOD+/-) with ethanolic solution of GTN (12.5 μg/min/kg for 4 d). For comparison, the tolerance-free pentaerithrityl tetranitrate (PETN, 1…