Search results for " mitochondria."

Physiological, morphological and metabolic changes in Tetrahymena pyriformis for the in vivo cytotoxicity assessment of metallic pollution: Impact on…

2007

Abstract The individual cytotoxicity of cadmium chloride, iron sulphate and chromium nitrate has been investigated by using the freshwater ciliate Tetrahymena pyriformis. The metabolic enzymes and antioxidant defense biomarkers were assessed. The results obtained reveal that their metal salts have perturbed the physiology and morphology of T. pyriformis. Also, the biomarkers assessed were sensitive to the presence of metal salts and this sensitivity was metal salt and dose dependant. To estimate the impact of their metal salts on mitochondria, we studied their effects in vivo and in vitro on the d -β-hydroxybutyrate dehydrogenase (BDH) (EC 1.1.1.30) inner mitochondrial membrane enzyme. The …

One Enzyme, Two Functions

2010

The human enzyme paraoxonase-2 (PON2) has two functions, an enzymatic lactonase activity and the reduction of intracellular oxidative stress. As a lactonase, it dominantly hydrolyzes bacterial signaling molecule 3OC12 and may contribute to the defense against pathogenic Pseudomonas aeruginosa. By its anti-oxidative effect, PON2 reduces cellular oxidative damage and influences redox signaling, which promotes cell survival. This may be appreciated but also deleterious given that high PON2 levels reduce atherosclerosis but may stabilize tumor cells. Here we addressed the unknown mechanisms and linkage of PON2 enzymatic and anti-oxidative function. We demonstrate that PON2 indirectly but specif…

Methionine Cycle Rewiring by Targeting miR-873-5p Modulates Ammonia Metabolism to Protect the Liver from Acetaminophen

2022

Drug-induced liver injury (DILI) development is commonly associated with acetaminophen (APAP) overdose, where glutathione scavenging leads to mitochondrial dysfunction and hepatocyte death. DILI is a severe disorder without effective late-stage treatment, since N-acetyl cysteine must be administered 8 h after overdose to be efficient. Ammonia homeostasis is altered during liver diseases and, during DILI, it is accompanied by decreased glycine N-methyltransferase (GNMT) expression and S-adenosylmethionine (AdoMet) levels that suggest a reduced methionine cycle. Anti-miR-873-5p treatment prevents cell death in primary hepatocytes and the appearance of necrotic areas in liver from APAP-adminis…

Brain glucose sensing and energy balance: role of mitochondrial reactive oxygen species

2012

Brain glucose sensing and energy balance: role of mitochondrial reactive oxygen species . 7. congrès de physiologie, de pharmacologie et de thérapeutique (P2T)

Rôle de la mitochondrie dans le glucose sensing cérébral

2014

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…

Cytoprotective Effect of Idebenone through Modulation of the Intrinsic Mitochondrial Pathway of Apoptosis in Human Retinal Pigment Epithelial Cells E…

2022

Idebenone is a ubiquinone short-chain synthetic analog with antioxidant properties, which is believed to restore mitochondrial ATP synthesis. As such, idebenone is investigated in numerous clinical trials for diseases of mitochondrial aetiology and it is authorized as a drug for the treatment of Leber’s hereditary optic neuropathy. Mitochondria of retinal pigment epithelium (RPE) are particularly vulnerable to oxidative damage associated with cellular senescence. Therefore, the aim of this study was to explore idebenone’s cytoprotective effect and its underlying mechanism. We used a human-RPE cell line (ARPE-19) exposed to idebenone pre-treatment for 24 h followed by conditions …

Towards the standardization of mitochondrial proteomics: the Italian mt-HPP initiative

2017

The mitochondrial Human Proteome Project aims at understanding the function of the mitochondrial proteome and its crosstalk with the proteome of other organelles. Being able to choose a suitable and validated enrichment protocol of functional mitochondria, based on the specific needs of the downstream proteomics analysis, would greatly help the researchers in the field. Mitochondrial fractions from ten model cell lines were prepared using three enrichment protocols and analyzed on seven different LC-MS/MS platforms. All data were processed using neXtProt as reference database. The data are available for the Human Proteome Project purposes through the ProteomeXchange Consortium with the iden…

Immunoaffinity purification and characterization of mitochondrial membrane-bound D-3-hydroxybutyrate dehydrogenase from Jaculus orientalis.

2008

Abstract Background The interconversion of two important energy metabolites, 3-hydroxybutyrate and acetoacetate (the major ketone bodies), is catalyzed by D-3-hydroxybutyrate dehydrogenase (BDH1: EC 1.1.1.30), a NAD+-dependent enzyme. The eukaryotic enzyme is bound to the mitochondrial inner membrane and harbors a unique lecithin-dependent activity. Here, we report an advanced purification method of the mammalian BDH applied to the liver enzyme from jerboa (Jaculus orientalis), a hibernating rodent adapted to extreme diet and environmental conditions. Results Purifying BDH from jerboa liver overcomes its low specific activity in mitochondria for further biochemical characterization of the e…

Retracted: Targeting Mitochondria as Therapeutic Strategy for Metabolic Disorders.

2019

Mitochondria are critical regulator of cell metabolism; thus, mitochondrial dysfunction is associated with many metabolic disorders. Defects in oxidative phosphorylation, ROS production, or mtDNA mutations are the main causes of mitochondrial dysfunction in many pathological conditions such as IR/diabetes, metabolic syndrome, cardiovascular diseases, and cancer. Thus, targeting mitochondria has been proposed as therapeutic approach for these conditions, leading to the development of small molecules to be tested in the clinical scenario. Here we discuss therapeutic interventions to treat mitochondrial dysfunction associated with two major metabolic disorders, metabolic syndrome, and cancer. …