Most cited article - PubMed ID 23220394
The function and the role of the mitochondrial glycerol-3-phosphate dehydrogenase in mammalian tissues
Life manifests as growth, movement or heat production that occurs thanks to the energy accepted from the outside environment. The basis of energy transduction attracted the Czech researchers since the beginning of the 20th century. It further accelerated after World War II, when the new Institute of Physiology was established in 1954. When it was found that energy is stored in the form of adenosine triphosphate (ATP) that can be used by numerous reactions as energy source and is produced in the process called oxidative phosphorylation localized in mitochondria, the investigation focused on this cellular organelle. Although the Czech scientists had to overcome various obstacles including Communist party leadership, driven by curiosity, boldness, and enthusiasm, they characterized broad spectrum of mitochondrial properties in different tissues in (patho)physiological conditions in collaboration with many world-known laboratories. The current review summarizes the contribution of the Czech scientists to the bioenergetic and mitochondrial research in the global context. Keywords: Mitochondria, Bioenergetics, Chemiosmotic coupling.
- MeSH
- Biomedical Research history trends MeSH
- History, 20th Century MeSH
- History, 21st Century MeSH
- Energy Metabolism * MeSH
- Humans MeSH
- Mitochondria * metabolism MeSH
- Animals MeSH
- Check Tag
- History, 20th Century MeSH
- History, 21st Century MeSH
- Humans MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
- Historical Article MeSH
- Review MeSH
- Geographicals
- Czech Republic MeSH
Rationale: Despite growing evidence for mitochondria's involvement in cancer, the roles of specific metabolic components outside the respiratory complex have been little explored. We conducted metabolomic studies on mitochondrial DNA (mtDNA)-deficient (ρ0) cancer cells with lower proliferation rates to clarify the undefined roles of mitochondria in cancer growth. Methods and results: Despite extensive metabolic downregulation, ρ0 cells exhibited high glycerol-3-phosphate (G3P) level, due to low activity of mitochondrial glycerol-3-phosphate dehydrogenase (GPD2). Knockout (KO) of GPD2 resulted in cell growth suppression as well as inhibition of tumor progression in vivo. Surprisingly, this was unrelated to the conventional bioenergetic function of GPD2. Instead, multi-omics results suggested major changes in ether lipid metabolism, for which GPD2 provides dihydroxyacetone phosphate (DHAP) in ether lipid biosynthesis. GPD2 KO cells exhibited significantly lower ether lipid level, and their slower growth was rescued by supplementation of a DHAP precursor or ether lipids. Mechanistically, ether lipid metabolism was associated with Akt pathway, and the downregulation of Akt/mTORC1 pathway due to GPD2 KO was rescued by DHAP supplementation. Conclusion: Overall, the GPD2-ether lipid-Akt axis is newly described for the control of cancer growth. DHAP supply, a non-bioenergetic process, may constitute an important role of mitochondria in cancer.
- Keywords
- DHAP, GPD2, cancer, ether lipids, mitochondria,
- MeSH
- Energy Metabolism MeSH
- Ethers metabolism MeSH
- Glycerolphosphate Dehydrogenase * genetics metabolism MeSH
- Humans MeSH
- Mitochondria * enzymology MeSH
- Mice MeSH
- Neoplasms * enzymology pathology MeSH
- Proto-Oncogene Proteins c-akt * metabolism MeSH
- Animals MeSH
- Check Tag
- Humans MeSH
- Mice MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Names of Substances
- Ethers MeSH
- Glycerolphosphate Dehydrogenase * MeSH
- Proto-Oncogene Proteins c-akt * MeSH
Lesniowski-Crohn's disease (CD) is a type of chronic inflammatory bowel disease (IBD) of uncertain etiology. Initially, pharmacological management is undertaken; however, surgical intervention is necessary to improve life quality and relieve symptoms in most cases. Here changes are reported in blood metabolome that occurred three days after the ileo-colic region resection in the case of seven patients. Alterations are observed in levels of metabolites associated with multiple mitochondrial pathways, based on the Metabolite Set Enrichment Analysis, reflecting a high energy demand in the post-operative period. As most of these metabolites are also essential nutrients supplied from foods, we believe that our results might contribute to the discussion on perioperative nutrition's role in enhanced recovery.
- Keywords
- Gas Chromatography-Mass Spectrometry (GC-MS), Lesniowski-Crohn’s disease, blood plasma metabolome, metabolomics,
- Publication type
- Journal Article MeSH
Prostate cancer is one of the most prominent cancers diagnosed in males. Contrasting with other cancer types, glucose utilization is not increased in prostate carcinoma cells as they employ different metabolic adaptations involving mitochondria as a source of energy and intermediates required for rapid cell growth. In this regard, prostate cancer cells were associated with higher activity of mitochondrial glycerol-3-phosphate dehydrogenase (mGPDH), the key rate limiting component of the glycerophosphate shuttle, which connects mitochondrial and cytosolic processes and plays significant role in cellular bioenergetics. Our research focused on the role of mGPDH biogenesis and regulation in prostate cancer compared to healthy cells. We show that the 42 amino acid presequence is cleaved from N-terminus during mGPDH biogenesis. Only the processed form is part of the mGPDH dimer that is the prominent functional enzyme entity. We demonstrate that mGPDH overexpression enhances the wound healing ability in prostate cancer cells. As mGPDH is at the crossroad of glycolysis, lipogenesis and oxidative metabolism, regulation of its activity by intramitochondrial processing might represent rapid means of cellular metabolic adaptations.
- Keywords
- GPD2 gene, metabolic adaptation, mitochondrial glycerol-3-phosphate dehydrogenase (EC:1.1.5.3), prostate cancer,
- MeSH
- Glycerolphosphate Dehydrogenase metabolism MeSH
- HEK293 Cells MeSH
- Humans MeSH
- Mitochondria genetics metabolism MeSH
- Cell Line, Tumor MeSH
- Prostatic Neoplasms genetics metabolism MeSH
- Transfection MeSH
- Check Tag
- Humans MeSH
- Male MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Names of Substances
- Glycerolphosphate Dehydrogenase MeSH
BACKGROUND: Comparative analyses have indicated that the mitochondrion of the last eukaryotic common ancestor likely possessed all the key core structures and functions that are widely conserved throughout the domain Eucarya. To date, such studies have largely focused on animals, fungi, and land plants (primarily multicellular eukaryotes); relatively few mitochondrial proteomes from protists (primarily unicellular eukaryotic microbes) have been examined. To gauge the full extent of mitochondrial structural and functional complexity and to identify potential evolutionary trends in mitochondrial proteomes, more comprehensive explorations of phylogenetically diverse mitochondrial proteomes are required. In this regard, a key group is the jakobids, a clade of protists belonging to the eukaryotic supergroup Discoba, distinguished by having the most gene-rich and most bacteria-like mitochondrial genomes discovered to date. RESULTS: In this study, we assembled the draft nuclear genome sequence for the jakobid Andalucia godoyi and used a comprehensive in silico approach to infer the nucleus-encoded portion of the mitochondrial proteome of this protist, identifying 864 candidate mitochondrial proteins. The A. godoyi mitochondrial proteome has a complexity that parallels that of other eukaryotes, while exhibiting an unusually large number of ancestral features that have been lost particularly in opisthokont (animal and fungal) mitochondria. Notably, we find no evidence that the A. godoyi nuclear genome has or had a gene encoding a single-subunit, T3/T7 bacteriophage-like RNA polymerase, which functions as the mitochondrial transcriptase in all eukaryotes except the jakobids. CONCLUSIONS: As genome and mitochondrial proteome data have become more widely available, a strikingly punctuate phylogenetic distribution of different mitochondrial components has been revealed, emphasizing that the pathways of mitochondrial proteome evolution are likely complex and lineage-specific. Unraveling this complexity will require comprehensive comparative analyses of mitochondrial proteomes from a phylogenetically broad range of eukaryotes, especially protists. The systematic in silico approach described here offers a valuable adjunct to direct proteomic analysis (e.g., via mass spectrometry), particularly in cases where the latter approach is constrained by sample limitation or other practical considerations.
- Keywords
- Andalucia godoyi, Jakobids, Mitochondrial evolution, Mitochondrial genome, Mitochondrial proteome, Mitochondrion, Protist,
- MeSH
- Cell Nucleus genetics MeSH
- Eukaryota genetics MeSH
- Genome, Mitochondrial * MeSH
- Mitochondrial Proteins genetics metabolism MeSH
- Proteome * MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Names of Substances
- Mitochondrial Proteins MeSH
- Proteome * MeSH
Metformin is widely prescribed as a first-choice antihyperglycemic drug for treatment of type 2 diabetes mellitus, and recent epidemiological studies showed its utility also in cancer therapy. Although it is in use since the 1970s, its molecular target, either for antihyperglycemic or antineoplastic action, remains elusive. However, the body of the research on metformin effect oscillates around mitochondrial metabolism, including the function of oxidative phosphorylation (OXPHOS) apparatus. In this study, we focused on direct inhibitory mechanism of biguanides (metformin and phenformin) on OXPHOS complexes and its functional impact, using the model of isolated brown adipose tissue mitochondria. We demonstrate that biguanides nonspecifically target the activities of all respiratory chain dehydrogenases (mitochondrial NADH, succinate, and glycerophosphate dehydrogenases), but only at very high concentrations (10-2-10-1 M) that highly exceed cellular concentrations observed during the treatment. In addition, these concentrations of biguanides also trigger burst of reactive oxygen species production which, in combination with pleiotropic OXPHOS inhibition, can be toxic for the organism. We conclude that the beneficial effect of biguanides should probably be associated with subtler mechanism, different from the generalized inhibition of the respiratory chain.
- MeSH
- Biguanides pharmacology MeSH
- Phenformin pharmacology MeSH
- Glycerolphosphate Dehydrogenase metabolism MeSH
- Adipose Tissue, Brown cytology MeSH
- Hypoglycemic Agents pharmacology MeSH
- Rats MeSH
- Succinic Acid metabolism MeSH
- Membrane Potential, Mitochondrial drug effects MeSH
- Metformin pharmacology MeSH
- Mitochondria drug effects metabolism MeSH
- Oxidation-Reduction drug effects MeSH
- Hydrogen Peroxide pharmacology MeSH
- Rats, Wistar MeSH
- Reactive Oxygen Species metabolism MeSH
- Animals MeSH
- Check Tag
- Rats MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
- Names of Substances
- Biguanides MeSH
- Phenformin MeSH
- Glycerolphosphate Dehydrogenase MeSH
- Hypoglycemic Agents MeSH
- Succinic Acid MeSH
- Metformin MeSH
- Hydrogen Peroxide MeSH
- Reactive Oxygen Species MeSH
Pericellular oxygen concentration represents an important factor in the regulation of cell functions, including cell differentiation, growth and mitochondrial energy metabolism. Hypoxia in adipose tissue has been associated with altered adipokine secretion profile and suggested as a possible factor in the development of type 2 diabetes. In vitro experiments provide an indispensable tool in metabolic research, however, physical laws of gas diffusion make prolonged exposure of adherent cells to desired pericellular O2 concentrations questionable. The aim of this study was to investigate the direct effect of various O2 levels (1%, 4% and 20% O2) on the proteomic profile and triglyceride accumulation in 3T3-L1 differentiated preadipocytes using gas-permeable cultureware. Following differentiation of cells under desired pericellular O2 concentrations, cell lysates were subjected to two-dimensional gel electrophoresis and protein visualization using Coomassie blue staining. Spots showing differential expression under hypoxia were analyzed using matrix-assisted laser desorption/ionization mass spectrometry. All identified proteins were subjected to pathway analysis. We observed that protein expression of 26 spots was reproducibly affected by 4% and 1% O2 (17 upregulated and 9 downregulated). Pathway analysis showed that mitochondrial energy metabolism and triglyceride synthesis were significantly upregulated by hypoxia. In conclusion, this study demonstrated the direct effects of pericellular O2 levels on adipocyte energy metabolism and triglyceride synthesis, probably mediated through the reversed tricarboxylic acid cycle flux.
- MeSH
- Electrophoresis, Gel, Two-Dimensional MeSH
- Cell Differentiation drug effects MeSH
- 3T3-L1 Cells MeSH
- Citric Acid Cycle drug effects MeSH
- Down-Regulation drug effects MeSH
- Cells, Cultured MeSH
- Oxygen pharmacology MeSH
- Lipids biosynthesis MeSH
- Lipogenesis drug effects MeSH
- Mice MeSH
- Permeability MeSH
- Gases chemistry MeSH
- Cell Count MeSH
- Proteomics * MeSH
- Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization MeSH
- Triglycerides metabolism MeSH
- Adipocytes cytology drug effects metabolism MeSH
- Up-Regulation drug effects MeSH
- Animals MeSH
- Check Tag
- Mice MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Names of Substances
- Oxygen MeSH
- Lipids MeSH
- Gases MeSH
- Triglycerides MeSH
BACKGROUND: Mitochondrial damage occurs in the acute phase of critical illness, followed by activation of mitochondrial biogenesis in survivors. It has been hypothesized that bioenergetics failure of skeletal muscle may contribute to the development of ICU-acquired weakness. The aim of the present study was to determine whether mitochondrial dysfunction persists until protracted phase of critical illness. METHODS: In this single-centre controlled-cohort ex vivo proof-of-concept pilot study, we obtained vastus lateralis biopsies from ventilated patients with ICU-acquired weakness (n = 8) and from age and sex-matched metabolically healthy controls (n = 8). Mitochondrial functional indices were measured in cytosolic context by high-resolution respirometry in tissue homogenates, activities of respiratory complexes by spectrophotometry and individual functional capacities were correlated with concentrations of electron transport chain key subunits from respiratory complexes II, III, IV and V measured by western blot. RESULTS: The ability of aerobic ATP synthesis (OXPHOS) was reduced to ~54% in ICU patients (p<0.01), in correlation with the depletion of complexes III (~38% of control, p = 0.02) and IV (~26% of controls, p<0.01) and without signs of mitochondrial uncoupling. When mitochondrial functional indices were adjusted to citrate synthase activity, OXPHOS and the activity of complexes I and IV were not different, whilst the activities of complexes II and III were increased in ICU patients 3-fold (p<0.01) respectively 2-fold (p<0.01). CONCLUSIONS: Compared to healthy controls, in ICU patients we have demonstrated a ~50% reduction of the ability of skeletal muscle to synthetize ATP in mitochondria. We found a depletion of complex III and IV concentrations and relative increases in functional capacities of complex II and glycerol-3-phosphate dehydrogenase/complex III.
- MeSH
- Adenosine Triphosphate metabolism physiology MeSH
- Organelle Biogenesis MeSH
- Quadriceps Muscle metabolism MeSH
- Energy Metabolism physiology MeSH
- Glycerolphosphate Dehydrogenase metabolism MeSH
- Intensive Care Units MeSH
- Cohort Studies MeSH
- Muscle, Skeletal metabolism MeSH
- Critical Illness MeSH
- Middle Aged MeSH
- Humans MeSH
- Mitochondria metabolism pathology MeSH
- Oxidative Stress physiology MeSH
- Pilot Projects MeSH
- Aged, 80 and over MeSH
- Aged MeSH
- Muscle Weakness etiology MeSH
- Check Tag
- Middle Aged MeSH
- Humans MeSH
- Male MeSH
- Aged, 80 and over MeSH
- Aged MeSH
- Female MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Names of Substances
- Adenosine Triphosphate MeSH
- Glycerolphosphate Dehydrogenase MeSH
BACKGROUND: Mitochondrial diseases belong to the most severe inherited metabolic disorders affecting pediatric population. Despite detailed knowledge of mtDNA mutations and progress in identification of affected nuclear genes, diagnostics of a substantial part of mitochondrial diseases relies on clinical symptoms and biochemical data from muscle biopsies and cultured fibroblasts. METHODS: To investigate manifestation of oxidative phosphorylation defects in isolated lymphocytes, digitonin-permeabilized cells from 48 children were analyzed by high resolution respirometry, cytofluorometric detection of mitochondrial membrane potential and immunodetection of respiratory chain proteins with SDS and Blue Native electrophoreses. RESULTS: Evaluation of individual respiratory complex activities, ATP synthesis, kinetic parameters of mitochondrial respiratory chain and the content and subunit composition of respiratory chain complexes enabled detection of inborn defects of respiratory complexes I, IV and V within 2 days. Low respiration with NADH-dependent substrates and increased respiration with glycerol-3-phosphate revealed complex I defects; changes in p 50 for oxygen and elevated uncoupling control ratio pointed to complex IV deficiency due to SURF1 or SCO2 mutation; high oligomycin sensitivity of state 3-ADP respiration, upregulated mitochondrial membrane potential and low content of complex V were found in lymphocytes with ATP synthase deficiency due to TMEM70 mutations. CONCLUSION: Based on our results, we propose the best biochemical parameters predictive for defects of respiratory complexes I, IV and V manifesting in peripheral blood lymphocytes. GENERAL SIGNIFICANCE: The noninvasiveness, reliability and speed of an approach utilizing novel biochemical criteria demonstrate the high potential of isolated lymphocytes for diagnostics of oxidative phosphorylation disorders in pediatric patients.
- Keywords
- AA, antimycin A, BNE, Blue Native PAGE, COX, cytochrome c oxidase, Diagnostics, FCCP, carbonyl cyanide 4-(trifluoromethoxy)phenylhydrazone, GP, glycerol-3-phosphate, GPDH, mitochondrial FAD-dependent glycerophosphate dehydrogenase, Lymphocytes, Mitochondrial diseases, OXPHOS, oxidative phosphorylation, Oxidative phosphorylation, PAGE, polyacrylamide gel electrophoresis, Respirometry, TMPD, tetramethylphenylenediamine, TMRM, tetramethylrhodamine methyl ester, cI–cV, respiratory chain complexes I–V, s3, state 3-ADP, s3u, state 3-uncoupled, s4o, state 4-oligomycin, ΔΨm, mitochondrial membrane potential,
- Publication type
- Journal Article MeSH