Search results for "MITOCHONDRION"

Exercise as a Model to Study Oxidative Stress

2011

Physical exercise generates free radicals. The major source of radicals in exercise appears to be extracellular. Our experiments show that xanthine oxidase is a key player in the generation of superoxide during exercise. Mitochondrial contribution appears to be less important: during high oxygen utilization by mitochondria in state 3, the proportion of oxygen that is converted to superoxide is on an order of magnitude lower than in resting, state 4 conditions. Exercise-induced radicals constitute a double-edged sword: high intensity ­exercise causes the generation of relatively high concentrations of radicals that cause oxidative stress and eventually damage. On the other hand, low intensit…

Magnesium and Alzheimer’s Disease

2015

Environmental factors, including nutrition and metal elements, are implicated in the pathophysiology of Alzheimer’s disease (AD). Several in vitro and in vivo data indicate a role for magnesium (Mg) in many biological and clinical aspects of AD. Mg deficiency, aside from having a negative impact on the energy production pathways required by the mitochondria to generate adenosine triphosphate, also affects many biochemical mechanisms vital for neuronal properties and synaptic plasticity, including the response of N-methyl- d -aspartate receptors to excitatory amino acids, stability, and viscosity of the cell membrane. Mg also has an action as a mild calcium antagonist, and as an antioxidant …

Centenarians overexpress BCL-xL, which confers them a protection against apoptosis, oxidative stress and immunosenescence

2015

Centenarians not only have an extraordinary longevity, but also show a compression of morbidity. They preserve the capacity of maintaining homeostasis, and this is the reason for them to reach such a long life. We studied their mRNA expression profile and identified 1721 mRNAs differentially expressed by centenarians when compared with septuagenarians and young people. A sub-network analysis showed six common genes: interferon, T-cell receptor, tumor necrosis factor, SP1 transcription factor, transforming growth factor and IL-32.These six centenarian-specific genes are related to Bcl-xL, Fas, and Fas ligand all of them involved in the control of apoptosis. RT-PCR analysis confirmed that cen…

Ver�nderungen an Proteinen der Leber und des Blutes bei experimenteller Lebercirrhose und nach Behandlung mit Decortin und einem anabolen Steroid

1963

Sjøgren's syndrome-associated oxidative stress and mitochondrial dysfunction: Prospects for chemoprevention trials

2012

An involvement of oxidative stress (OS) was found in recent studies of Sjøgren's syndrome (SS) that reported significant changes in protein oxidation, myeloperoxidase activity, TNF-α, nitrotyrosine, and GSH levels in plasma from SS patients. Excess levels of OS markers, as oxidative DNA damage and propanoyl-lysine, were reported in saliva from SS patients. Previous reports concurred with a role of OS in SS pathogenesis, by showing a decreased expression of antioxidant activities in conjunctival epithelial cells of SS patients and in parotid gland tissue samples from SS patients. A link between OS and mitochondrial dysfunction (MDF) is recognized both on the grounds of the established role o…

Polyunsaturated n-3 and n-6 fatty acids at a low level in the diet alter mitochondrial outer membrane parameters in Wistar rat liver

1995

Abstract This study was designed to examine whether n-3 and n-6 polyunsaturated fatty acids (PUFA) at a very low level in the diet (about 0.2%) may alter the fatty acid composition of mitochondrial outer membranes and the characteristics of carnitine palmitoyltransferase I (CPTI) activity in the liver of normal Wistar rats. The animals were fed diets containing different oil mixtures (5% wt/wt) with the same ratio of n-6 n-3 fatty acids supplied either as fish oil or arachidonic acid concentrate. The cholesterol content of the mitochondrial outer membranes from liver was similar for all diets, while the percentage of 22:6n-3 and 20:4n-6 in phospholipids was enhanced with the diets containin…

Liver mitochondria and insulin resistance

2010

Sex-specific reaction of liver ultrastructure in zebra fish (Brachydanio rerio) after prolonged sublethal exposure to 4-nitrophenol

1989

Abstract Morphological alterations of the liver of zebra fish ( Brachydanio rerio ) following prolonged exposure to 0.1, 1 and 5 mg · l −1 4-nitrophenol (4-NP) were investigated by means of light and electron microscopy. Based on marked sexual dimorphism in control animals, liver recactions were both sex- and dose-dependent. Whereas at 0.1 mg·1 −1 only minor changes could be revealed, there were numerous structural modifications at 1 mg·1 −1 : Whereas male fish primarily react with a proliferation of smooth endoplasmic reticulum, female fish display a high degree of fenetrastion within cisternate of the rough endoplasmic reticulum. Both sexes exhibit infiltration of macrophages and lymphocy…

Aging of the liver: Age-associated mitochondrial damage in intact hepatocytes

1996

Mitochondrial damage may be a major cause of cellular aging. So far, this hypothesis had only been tested using isolated mitochondria. The aim of this study was to investigate the involvement of mitochondria in aging using whole liver cells and not isolated mitochondria only. Using flow cytometry, we found that age is associated with a decrease in mitochondrial membrane potential (30%), an increase in mitochondrial size, and an increase in mitochondrial peroxide generation (23%). Intracellular peroxide levels were also increased. The number of mitochondria per cell and inner mitochondrial membrane mass did not change. Gluconeogenesis from glycerol or fructose (mitochondrial-independent) did…

Lysosomal trafficking in rat cardiac myocytes.

1990

By immunolabeling of cryosections, we have characterized in rat cardiac myocytes the cation-independent mannose-6-phosphate receptor (MPR), a lysosomal membrane glycoprotein, lgp120, and a lysosomal enzyme, MEP (homologous to cathepsin L). Most of the MPR label was located in large membrane-filled structures (MPR structures) in large clusters of mitochondria adjacent to but distinct from the Golgi complex. Lpg120 and MEP showed typical lysosomal localization throughout the cell, often associated with regions that appeared to contain autophagosome-like structures. In addition, MEP and lgp120 co-localized within MPR structures. MEP and MPR were localized inside the lumen of MPR structures. M…