Search results for "Mitochondrial protein"
showing 9 items of 89 documents
Characterisation of fascioliasis lymnaeid intermediate hosts from Chile by DNA sequencing, with emphasis on Lymnaea viator and Galba truncatula.
2011
In South America, Fasciola hepatica infection poses serious health problems in both humans and livestock. In Chile, the medical impact appears yearly stable and mainly concentrated in central regions, where the veterinary problem is highlighted by higher animal prevalences. Studies were undertaken by rDNA ITS-2 and ITS-1 and mtDNA cox1 sequencing to clarify the specific status of the lymnaeids, their geographical distribution and fascioliasis transmission capacity in Chile, by comparison with other American countries and continents. Results change the lymnaeid scenario known so far. The lymnaeid fauna of mainland Chile shows to be poor, including only two authochthonous species, Lymnaea via…
Oral administration of vitamin C decreases muscle mitochondrial biogenesis and hampers training-induced adaptations in endurance performance
2008
Background Exercise practitioners often take vitamin C supplements because intense muscular contractile activity can result in oxidative stress, as indicated by altered muscle and blood glutathione concentrations and increases in protein, DNA, and lipid peroxidation. There is, however, considerable debate regarding the beneficial health effects of vitamin C supplementation. Objective This study was designed to study the effect of vitamin C on training efficiency in rats and in humans. Design The human study was double-blind and randomized. Fourteen men (27-36 y old) were trained for 8 wk. Five of the men were supplemented daily with an oral dose of 1 g vitamin C. In the animal study, 24 mal…
Induction of mitochondrial xanthine oxidase activity during apoptosis in the rat mammary gland
2006
Oxidative stress is an important signal for apoptosis to start. So far the mitochondrial respiratory chain has been considered as the major, if not the only, cause of such stress. Here we report that this is not the case. Xanthine oxidase, a O2(-) and H2O2 generating enzyme which is important in causing significant oxidative stress in the cytosol, is also present in the mitochondrial fraction of rat mammary gland. After weaning, during the involution of the mammary gland, massive apoptosis occurs. Mitochondrial xanthine oxidase activity increases and high mitochondrial H2O2 production takes place. Inhibition of xanthine oxidase activity by allopurinol, a specific inhibitor of xanthine oxida…
Hsp 56 mRNA in Paracentrotus lividus embryos binds to a mitochondrial protein
2007
We previously demonstrated that Paracentrotus lividus Hsp56 mitochondrial chaperonin is constitutively expressed during development, that it has a specific territorial distribution, both in normal and heat-shocked embryos, and that its amount increases after heat shock [Roccheri MC, Patti M, Agnello M, Gianguzza F, Carra E, Rinaldi AM. Localization of mitochondrial Hsp56 chaperonin during sea urchin development. Biochem Biophys Res Commun 2001;287:1093-98] and cadmium treatment [Roccheri MC, Agnello M, Boneventura R, Matranga V. Cadmium induces the expression of specific stress proteins in sea urchin embryos. Biochem Biophys Res Commun 2004;321:80-7]. In this study, we looked at Hsp56 mRNA …
Hsp60 Protects against Amyloid β Oligomer Synaptic Toxicity via Modification of Toxic Oligomer Conformation
2019
Alzheimer's disease (AD) is the leading cause of dementia worldwide. While the etiology of AD remains uncertain, neurotoxic effects of amyloid beta oligomers (Aβo) on synaptic function, a well-established early event in AD, is an attractive area for the development of novel strategies to modify or cease the disease's progression. In this work, we tested the protective action of the mitochondrial chaperone Hsp60 against Aβo neurotoxicity, by determining the direct effect of Hsp60 in changing Aβo toxic conformations and thus reducing their dysfunctional synaptic binding and consequent suppression of long-term potentiation. Our data suggest that Hsp60 has a direct impact on Aβo, resulting in a…
Stability and disassembly properties of human naïve Hsp60 and bacterial GroEL chaperonins.
2015
Human Hsp60 chaperonin and its bacterial homolog GroEL, in association with the corresponding co-chaperonins Hsp10 and GroES, constitute important chaperone systems promoting the proper folding of several mitochondrial proteins. Hsp60 is also currently described as a ubiquitous molecule with multiple roles both in health conditions and in several diseases. Naïve Hsp60 bearing the mitochondrial import signal has been recently demonstrated to present different oligomeric organizations with respect to GroEL, suggesting new possible physiological functions. Here we present a combined investigation with circular dichroism and small-angle X-ray scattering of structure, self-organization, and sta…
The NG2 Proteoglycan Protects Oligodendrocyte Precursor Cells against Oxidative Stress via Interaction with OMI/HtrA2.
2015
The NG2 proteoglycan is characteristically expressed by oligodendrocyte progenitor cells (OPC) and also by aggressive brain tumours highly resistant to chemo- and radiation therapy. Oligodendrocyte-lineage cells are particularly sensitive to stress resulting in cell death in white matter after hypoxic or ischemic insults of premature infants and destruction of OPC in some types of Multiple Sclerosis lesions. Here we show that the NG2 proteoglycan binds OMI/HtrA2, a mitochondrial serine protease which is released from damaged mitochondria into the cytosol in response to stress. In the cytosol, OMI/HtrA2 initiates apoptosis by proteolytic degradation of anti-apoptotic factors. OPC in which NG…
Superfood for axons: Glial exosomes boost axonal energetics by delivery of SIRT2
2021
Axon integrity depends on support by glia facilitating axonal maintenance and energy homeostasis, but the molecular mechanisms are not well understood. In this issue of Neuron, Chamberlain et al. (2021) provide evidence that oligodendrocyte-to-axon transfer of SIRT2 via extracellular vesicles (exosomes) enables deacetylation of mitochondrial proteins, enhancing axonal energy production.