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Manzoli R, Badenetti L, Bruzzone M, Macario MC, Rubin M, Dal Maschio M, Roveri A, Moro E. Mucopolysaccharidosis type II zebrafish model exhibits early impaired proteasomal-mediated degradation of the axon guidance receptor Dcc. Cell Death Dis 2024; 15:269. [PMID: 38627369 PMCID: PMC11021486 DOI: 10.1038/s41419-024-06661-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2023] [Revised: 04/02/2024] [Accepted: 04/08/2024] [Indexed: 04/19/2024]
Abstract
Most of the patients affected by neuronopathic forms of Mucopolysaccharidosis type II (MPS II), a rare lysosomal storage disorder caused by defects in iduronate-2-sulfatase (IDS) activity, exhibit early neurological defects associated with white matter lesions and progressive behavioural abnormalities. While neuronal degeneration has been largely described in experimental models and human patients, more subtle neuronal pathogenic defects remain still underexplored. In this work, we discovered that the axon guidance receptor Deleted in Colorectal Cancer (Dcc) is significantly dysregulated in the brain of ids mutant zebrafish since embryonic stages. In addition, thanks to the establishment of neuronal-enriched primary cell cultures, we identified defective proteasomal degradation as one of the main pathways underlying Dcc upregulation in ids mutant conditions. Furthermore, ids mutant fish-derived primary neurons displayed higher levels of polyubiquitinated proteins and P62, suggesting a wider defect in protein degradation. Finally, we show that ids mutant larvae display an atypical response to anxiety-inducing stimuli, hence mimicking one of the characteristic features of MPS II patients. Our study provides an additional relevant frame to MPS II pathogenesis, supporting the concept that multiple developmental defects concur with early childhood behavioural abnormalities.
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Affiliation(s)
- Rosa Manzoli
- Department of Molecular Medicine, University of Padova, 35121, Padova, Italy.
- Department of Biology, University of Padova, 35121, Padova, Italy.
| | - Lorenzo Badenetti
- Department of Molecular Medicine, University of Padova, 35121, Padova, Italy
- Department of Women's and Children's Health, University of Padova, 35128, Padova, Italy
- Istituto di Ricerca Pediatrica "Città Della Speranza", 35127, Padova, Italy
| | - Matteo Bruzzone
- Department of Biomedical Sciences, University of Padova, 35121, Padova, Italy
- Padua Neuroscience Center - PNC, University of Padova, 35129, Padova, Italy
| | - Maria Carla Macario
- Department of Molecular Medicine, University of Padova, 35121, Padova, Italy
- Department of Biology, University of Padova, 35121, Padova, Italy
| | - Michela Rubin
- Department of Molecular Medicine, University of Padova, 35121, Padova, Italy
| | - Marco Dal Maschio
- Department of Biomedical Sciences, University of Padova, 35121, Padova, Italy
- Padua Neuroscience Center - PNC, University of Padova, 35129, Padova, Italy
| | - Antonella Roveri
- Department of Molecular Medicine, University of Padova, 35121, Padova, Italy
| | - Enrico Moro
- Department of Molecular Medicine, University of Padova, 35121, Padova, Italy.
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2
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Valenti GE, Roveri A, Venerando R, Menichini P, Monti P, Tasso B, Traverso N, Domenicotti C, Marengo B. PTC596-Induced BMI-1 Inhibition Fights Neuroblastoma Multidrug Resistance by Inducing Ferroptosis. Antioxidants (Basel) 2023; 13:3. [PMID: 38275623 PMCID: PMC10812464 DOI: 10.3390/antiox13010003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2023] [Revised: 12/11/2023] [Accepted: 12/13/2023] [Indexed: 01/27/2024] Open
Abstract
Neuroblastoma (NB) is a paediatric cancer with noteworthy heterogeneity ranging from spontaneous regression to high-risk forms that are characterised by cancer relapse and the acquisition of drug resistance. The most-used anticancer drugs exert their cytotoxic effect by inducing oxidative stress, and long-term therapy has been demonstrated to cause chemoresistance by enhancing the antioxidant response of NB cells. Taking advantage of an in vitro model of multidrug-resistant (MDR) NB cells, characterised by high levels of glutathione (GSH), the overexpression of the oncoprotein BMI-1, and the presence of a mutant P53 protein, we investigated a new potential strategy to fight chemoresistance. Our results show that PTC596, an inhibitor of BMI-1, exerted a high cytotoxic effect on MDR NB cells, while PRIMA-1MET, a compound able to reactivate mutant P53, had no effect on the viability of MDR cells. Furthermore, both PTC596 and PRIMA-1MET markedly reduced the expression of epithelial-mesenchymal transition proteins and limited the clonogenic potential and the cancer stemness of MDR cells. Of particular interest is the observation that PTC596, alone or in combination with PRIMA-1MET and etoposide, significantly reduced GSH levels, increased peroxide production, stimulated lipid peroxidation, and induced ferroptosis. Therefore, these findings suggest that PTC596, by inhibiting BMI-1 and triggering ferroptosis, could be a promising approach to fight chemoresistance.
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Affiliation(s)
- Giulia Elda Valenti
- Department of Experimental Medicine, General Pathology Section, University of Genoa, 16132 Genoa, Italy; (G.E.V.); (N.T.); (B.M.)
| | - Antonella Roveri
- Department of Molecular Medicine, University of Padua, 35128 Padua, Italy; (A.R.); (R.V.)
| | - Rina Venerando
- Department of Molecular Medicine, University of Padua, 35128 Padua, Italy; (A.R.); (R.V.)
| | - Paola Menichini
- Mutagenesis and Cancer Prevention Unit, IRCCS Ospedale Policlinico San Martino, 16132 Genoa, Italy; (P.M.); (P.M.)
| | - Paola Monti
- Mutagenesis and Cancer Prevention Unit, IRCCS Ospedale Policlinico San Martino, 16132 Genoa, Italy; (P.M.); (P.M.)
| | - Bruno Tasso
- Department of Pharmacy, University of Genoa, 16148 Genoa, Italy;
| | - Nicola Traverso
- Department of Experimental Medicine, General Pathology Section, University of Genoa, 16132 Genoa, Italy; (G.E.V.); (N.T.); (B.M.)
| | - Cinzia Domenicotti
- Department of Experimental Medicine, General Pathology Section, University of Genoa, 16132 Genoa, Italy; (G.E.V.); (N.T.); (B.M.)
| | - Barbara Marengo
- Department of Experimental Medicine, General Pathology Section, University of Genoa, 16132 Genoa, Italy; (G.E.V.); (N.T.); (B.M.)
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3
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Roveri A, Di Giacinto F, Rossetto M, Cozza G, Cheng Q, Miotto G, Zennaro L, Di Paolo ML, Arnér ESJ, De Spirito M, Maiorino M, Ursini F. Cardiolipin drives the catalytic activity of GPX4 on membranes: Insights from the R152H mutant. Redox Biol 2023; 64:102806. [PMID: 37413766 DOI: 10.1016/j.redox.2023.102806] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2023] [Revised: 06/28/2023] [Accepted: 06/30/2023] [Indexed: 07/08/2023] Open
Abstract
The aim of this study was to examine, in biochemical detail, the functional role of the Arg152 residue in the selenoprotein Glutathione Peroxidase 4 (GPX4), whose mutation to His is involved in Sedaghatian-type Spondylometaphyseal Dysplasia (SSMD). Wild-type and mutated recombinant enzymes with selenopcysteine (Sec) at the active site, were purified and structurally characterized to investigate the impact of the R152H mutation on enzymatic function. The mutation did not affect the peroxidase reaction's catalytic mechanism, and the kinetic parameters were qualitatively similar between the wild-type enzyme and the mutant when mixed micelles and monolamellar liposomes containing phosphatidylcholine and its hydroperoxide derivatives were used as substrate. However, in monolamellar liposomes also containing cardiolipin, which binds to a cationic area near the active site of GPX4, including residue R152, the wild-type enzyme showed a non-canonical dependency of the reaction rate on the concentration of both enzyme and membrane cardiolipin. To explain this oddity, a minimal model was developed encompassing the kinetics of both the enzyme interaction with the membrane and the catalytic peroxidase reaction. Computational fitting of experimental activity recordings showed that the wild-type enzyme was surface-sensing and prone to "positive feedback" in the presence of cardiolipin, indicating a positive cooperativity. This feature was minimal, if any, in the mutant. These findings suggest that GPX4 physiology in cardiolipin containing mitochondria is unique, and emerges as a likely target of the pathological dysfunction in SSMD.
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Affiliation(s)
| | - Flavio Di Giacinto
- Neuroscience Department, Biophysics Section, Università Cattolica del Sacro Cuore, Rome, Italy
| | - Monica Rossetto
- Department of Molecular Medicine, University of Padova, Italy
| | - Giorgio Cozza
- Department of Molecular Medicine, University of Padova, Italy
| | - Qing Cheng
- Division of Biochemistry, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, 17177, Sweden
| | - Giovanni Miotto
- Department of Molecular Medicine, University of Padova, Italy
| | - Lucio Zennaro
- Department of Molecular Medicine, University of Padova, Italy
| | | | - Elias S J Arnér
- Division of Biochemistry, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, 17177, Sweden; Department of Selenoprotein Research and the National Tumor Biology Laboratory, National Institute of Oncology, Budapest, Hungary
| | - Marco De Spirito
- Neuroscience Department, Biophysics Section, Università Cattolica del Sacro Cuore, Rome, Italy
| | | | - Fulvio Ursini
- Department of Molecular Medicine, University of Padova, Italy.
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4
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Ursini F, Bosello Travain V, Cozza G, Miotto G, Roveri A, Toppo S, Maiorino M. A white paper on Phospholipid Hydroperoxide Glutathione Peroxidase (GPx4) forty years later. Free Radic Biol Med 2022; 188:117-133. [PMID: 35718302 DOI: 10.1016/j.freeradbiomed.2022.06.227] [Citation(s) in RCA: 29] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/19/2022] [Revised: 06/10/2022] [Accepted: 06/13/2022] [Indexed: 12/25/2022]
Abstract
The purification of a protein inhibiting lipid peroxidation led to the discovery of the selenoperoxidase GPx4 forty years ago. Thus, the evidence of the enzymatic activity was reached after identifying the biological effect and unambiguously defined the relationship between the biological function and the enzymatic activity. In the syllogism where GPx4 inhibits lipid peroxidation and its inhibition is lethal, cell death is operated by lipid peroxidation. Based on this rationale, this form of cell death emerged as regulated iron-enforced oxygen toxicity and was named ferroptosis in 2012. In the last decades, we learned that reduction of lipid hydroperoxides is indispensable and, in cooperation with prooxidant systems, controls the critical steady state of lipid peroxidation. This concept defined the GPx4 reaction as both the target for possible anti-cancer therapy and if insufficient, as cause of degenerative diseases. We know the reaction mechanism, but the details of the interaction at the membrane cytosol interface are still poorly defined. We know the gene structure, but the knowledge about expression control is still limited. The same holds true for post-transcriptional modifications. Reverse genetics indicate that GPx4 has a role in inflammation, immunity, and differentiation, but the observations emerging from these studies need a more specifically addressed biochemical evidence. Finally, the role of GPx4 in spermatogenesis disclosed an area unconnected to lipid peroxidation. In its mitochondrial and nuclear form, the peroxidase catalyzes the oxidation of protein thiols in two specific aspects of sperm maturation: stabilization of the mid-piece and chromatin compaction. Thus, although available evidence converges to the notion that GPx4 activity is vital due to the inhibition of lipid peroxidation, it is reasonable to foresee other unknown aspects of the GPx4 reaction to be disclosed.
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Affiliation(s)
- Fulvio Ursini
- Department of Molecular Medicine, Viale G. Colombo, 3, University of Padova, 35121, Padova, Italy
| | | | - Giorgio Cozza
- Department of Molecular Medicine, Viale G. Colombo, 3, University of Padova, 35121, Padova, Italy
| | - Giovanni Miotto
- Department of Molecular Medicine, Viale G. Colombo, 3, University of Padova, 35121, Padova, Italy
| | - Antonella Roveri
- Department of Molecular Medicine, Viale G. Colombo, 3, University of Padova, 35121, Padova, Italy
| | - Stefano Toppo
- Department of Molecular Medicine, Viale G. Colombo, 3, University of Padova, 35121, Padova, Italy
| | - Matilde Maiorino
- Department of Molecular Medicine, Viale G. Colombo, 3, University of Padova, 35121, Padova, Italy.
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5
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Romani P, Nirchio N, Arboit M, Barbieri V, Tosi A, Michielin F, Shibuya S, Benoist T, Wu D, Hindmarch CCT, Giomo M, Urciuolo A, Giamogante F, Roveri A, Chakravarty P, Montagner M, Calì T, Elvassore N, Archer SL, De Coppi P, Rosato A, Martello G, Dupont S. Mitochondrial fission links ECM mechanotransduction to metabolic redox homeostasis and metastatic chemotherapy resistance. Nat Cell Biol 2022; 24:168-180. [PMID: 35165418 PMCID: PMC7615745 DOI: 10.1038/s41556-022-00843-w] [Citation(s) in RCA: 63] [Impact Index Per Article: 31.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2020] [Accepted: 01/06/2022] [Indexed: 01/07/2023]
Abstract
Metastatic breast cancer cells disseminate to organs with a soft microenvironment. Whether and how the mechanical properties of the local tissue influence their response to treatment remains unclear. Here we found that a soft extracellular matrix empowers redox homeostasis. Cells cultured on a soft extracellular matrix display increased peri-mitochondrial F-actin, promoted by Spire1C and Arp2/3 nucleation factors, and increased DRP1- and MIEF1/2-dependent mitochondrial fission. Changes in mitochondrial dynamics lead to increased production of mitochondrial reactive oxygen species and activate the NRF2 antioxidant transcriptional response, including increased cystine uptake and glutathione metabolism. This retrograde response endows cells with resistance to oxidative stress and reactive oxygen species-dependent chemotherapy drugs. This is relevant in a mouse model of metastatic breast cancer cells dormant in the lung soft tissue, where inhibition of DRP1 and NRF2 restored cisplatin sensitivity and prevented disseminated cancer-cell awakening. We propose that targeting this mitochondrial dynamics- and redox-based mechanotransduction pathway could open avenues to prevent metastatic relapse.
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Affiliation(s)
- Patrizia Romani
- Department of Molecular Medicine (DMM), University of Padua, Padua, Italy
| | - Nunzia Nirchio
- Department of Molecular Medicine (DMM), University of Padua, Padua, Italy
| | - Mattia Arboit
- Department of Biology (DiBio), University of Padua, Padua, Italy
| | - Vito Barbieri
- Department of Surgery, Oncology and Gastroenterology (DiSCOG), University of Padua, Padua, Italy
- Veneto Institute of Oncology IOV-IRCCS, Padua, Italy
| | - Anna Tosi
- Veneto Institute of Oncology IOV-IRCCS, Padua, Italy
| | - Federica Michielin
- Institute of Child Health, NIHR Biomedical Research Centre, Great Ormond Street Institute of Child Health, UCL, London, UK
| | - Soichi Shibuya
- Institute of Child Health, NIHR Biomedical Research Centre, Great Ormond Street Institute of Child Health, UCL, London, UK
| | - Thomas Benoist
- Institute of Child Health, NIHR Biomedical Research Centre, Great Ormond Street Institute of Child Health, UCL, London, UK
| | - Danchen Wu
- Department of Medicine, Queen's University, Kingston, Ontario, Canada
| | | | - Monica Giomo
- Department of Industrial Engineering (DII), University of Padua, Padua, Italy
- Venetian Institute of Molecular Medicine (VIMM), Padua, Italy
| | - Anna Urciuolo
- Department of Molecular Medicine (DMM), University of Padua, Padua, Italy
- Fondazione Istituto di Ricerca Pediatrica (IRP), Città della Speranza, Padua, Italy
| | - Flavia Giamogante
- Department of Biomedical Sciences (DSB), University of Padua, Padua, Italy
| | - Antonella Roveri
- Department of Molecular Medicine (DMM), University of Padua, Padua, Italy
| | | | - Marco Montagner
- Department of Molecular Medicine (DMM), University of Padua, Padua, Italy
| | - Tito Calì
- Department of Biomedical Sciences (DSB), University of Padua, Padua, Italy
| | - Nicola Elvassore
- Institute of Child Health, NIHR Biomedical Research Centre, Great Ormond Street Institute of Child Health, UCL, London, UK
- Department of Industrial Engineering (DII), University of Padua, Padua, Italy
- Venetian Institute of Molecular Medicine (VIMM), Padua, Italy
| | - Stephen L Archer
- Department of Medicine, Queen's University, Kingston, Ontario, Canada
| | - Paolo De Coppi
- Institute of Child Health, NIHR Biomedical Research Centre, Great Ormond Street Institute of Child Health, UCL, London, UK
| | - Antonio Rosato
- Department of Surgery, Oncology and Gastroenterology (DiSCOG), University of Padua, Padua, Italy
- Veneto Institute of Oncology IOV-IRCCS, Padua, Italy
| | | | - Sirio Dupont
- Department of Molecular Medicine (DMM), University of Padua, Padua, Italy.
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6
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Queiroz RF, Stanley CP, Wolhuter K, Kong SMY, Rajivan R, McKinnon N, Nguyen GTH, Roveri A, Guttzeit S, Eaton P, Donald WA, Ursini F, Winterbourn CC, Ayer A, Stocker R. Hydrogen peroxide signaling via its transformation to a stereospecific alkyl hydroperoxide that escapes reductive inactivation. Nat Commun 2021; 12:6626. [PMID: 34785665 PMCID: PMC8595612 DOI: 10.1038/s41467-021-26991-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Accepted: 10/28/2021] [Indexed: 11/16/2022] Open
Abstract
During systemic inflammation, indoleamine 2,3-dioxygenase 1 (IDO1) becomes expressed in endothelial cells where it uses hydrogen peroxide (H2O2) to oxidize L-tryptophan to the tricyclic hydroperoxide, cis-WOOH, that then relaxes arteries via oxidation of protein kinase G 1α. Here we show that arterial glutathione peroxidases and peroxiredoxins that rapidly eliminate H2O2, have little impact on relaxation of IDO1-expressing arteries, and that purified IDO1 forms cis-WOOH in the presence of peroxiredoxin 2. cis-WOOH oxidizes protein thiols in a selective and stereospecific manner. Compared with its epimer trans-WOOH and H2O2, cis-WOOH reacts slower with the major arterial forms of glutathione peroxidases and peroxiredoxins while it reacts more readily with its target, protein kinase G 1α. Our results indicate a paradigm of redox signaling by H2O2 via its enzymatic conversion to an amino acid-derived hydroperoxide that 'escapes' effective reductive inactivation to engage in selective oxidative activation of key target proteins.
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Affiliation(s)
- Raphael F Queiroz
- Department of Natural Sciences, Southwest Bahia State University, Vitoria da Conquista, Bahia, Brazil
- Victor Chang Cardiac Research Institute, Darlinghurst, New South Wales, Australia
| | - Christopher P Stanley
- Victor Chang Cardiac Research Institute, Darlinghurst, New South Wales, Australia
- Heart Research Institute, The University of Sydney, Sydney, Australia
| | - Kathryn Wolhuter
- Victor Chang Cardiac Research Institute, Darlinghurst, New South Wales, Australia
| | | | - Ragul Rajivan
- Victor Chang Cardiac Research Institute, Darlinghurst, New South Wales, Australia
| | - Naomi McKinnon
- Victor Chang Cardiac Research Institute, Darlinghurst, New South Wales, Australia
| | - Giang T H Nguyen
- School of Chemistry, University of New South Wales, Sydney, New South Wales, Australia
| | - Antonella Roveri
- Department of Molecular Medicine, University of Padova, Padova, Italy
| | | | - Philip Eaton
- William Harvey Research Institute, Barts and the London School of Medicine, Queen Mary University of London, London, UK
| | - William A Donald
- School of Chemistry, University of New South Wales, Sydney, New South Wales, Australia
| | - Fulvio Ursini
- Department of Molecular Medicine, University of Padova, Padova, Italy
| | - Christine C Winterbourn
- Centre for Free Radical Research, Department of Pathology, University of Otago Christchurch, Christchurch, New Zealand
| | - Anita Ayer
- Victor Chang Cardiac Research Institute, Darlinghurst, New South Wales, Australia.
- Heart Research Institute, The University of Sydney, Sydney, Australia.
- St Vincent's Clinical School, University of New South Wales, Sydney, New South Wales, Australia.
| | - Roland Stocker
- Victor Chang Cardiac Research Institute, Darlinghurst, New South Wales, Australia.
- Heart Research Institute, The University of Sydney, Sydney, Australia.
- St Vincent's Clinical School, University of New South Wales, Sydney, New South Wales, Australia.
- School of Life and Environmental Sciences, The University of Sydney, Sydney, Australia.
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Cheng Q, Roveri A, Cozza G, Bordin L, Rohn I, Schwerdtle T, Kipp A, Ursini F, Maiorino M, Miotto G, Arnér ESJ. Production and purification of homogenous recombinant human selenoproteins reveals a unique codon skipping event in E. coli and GPX4-specific affinity to bromosulfophthalein. Redox Biol 2021; 46:102070. [PMID: 34304108 PMCID: PMC8326192 DOI: 10.1016/j.redox.2021.102070] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2021] [Revised: 07/13/2021] [Accepted: 07/13/2021] [Indexed: 01/18/2023] Open
Abstract
Selenoproteins are translated via animal domain-specific elongation machineries that redefine dedicated UGA opal codons from termination of translation to selenocysteine (Sec) insertion, utilizing specific tRNA species and Sec-specific elongation factors. This has made recombinant production of mammalian selenoproteins in E. coli technically challenging but recently we developed a methodology that enables such production, using recoding of UAG for Sec in an RF1-deficient host strain. Here we used that approach for production of the human glutathione peroxidases 1, 2 and 4 (GPX1, GPX2 and GPX4), with all these three enzymes being important antioxidant selenoproteins. Among these, GPX4 is the sole embryonically essential enzyme, and is also known to be essential for spermatogenesis as well as protection from cell death through ferroptosis. Enzyme kinetics, ICP-MS and mass spectrometry analyses of the purified recombinant proteins were used to characterize selenoprotein characteristics and their Sec contents. This revealed a unique phenomenon of one-codon skipping, resulting in a lack of a single amino acid at the position corresponding to the selenocysteine (Sec) residue, in about 30% of the recombinant GPX isoenzyme products. We furthermore confirmed the previously described UAG suppression with Lys or Gln as well as a minor suppression with Tyr, together resulting in about 20% Sec contents in the full-length proteins. No additional frameshifts or translational errors were detected. We subsequently found that Sec-containing GPX4 could be further purified over a bromosulfophthalein-column, yielding purified recombinant GPX4 with close to complete Sec contents. This production method for homogenously purified GPX4 should help to further advance the studies of this important selenoprotein.
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Affiliation(s)
- Qing Cheng
- Division of Biochemistry, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, SE-171 77, Stockholm, Sweden
| | - Antonella Roveri
- Department of Molecular Medicine, University of Padova, Padova, Italy
| | - Giorgio Cozza
- Department of Molecular Medicine, University of Padova, Padova, Italy
| | - Luciana Bordin
- Department of Molecular Medicine, University of Padova, Padova, Italy
| | - Isabelle Rohn
- University of Potsdam, Institute of Nutritional Science, Department of Food Chemistry, Nuthetal, Germany
| | - Tanja Schwerdtle
- University of Potsdam, Institute of Nutritional Science, Department of Food Chemistry, Nuthetal, Germany; German Federal Institute for Risk Assessment (BfR), Berlin, Germany
| | - Anna Kipp
- Friedrich Schiller University Jena, Institute of Nutritional Sciences, Molecular Nutritional Physiology, Jena, Germany
| | - Fulvio Ursini
- Department of Molecular Medicine, University of Padova, Padova, Italy
| | - Matilde Maiorino
- Department of Molecular Medicine, University of Padova, Padova, Italy
| | - Giovanni Miotto
- Department of Molecular Medicine, University of Padova, Padova, Italy; CRIBI Biotechnology Center, University of Padova, Padova, Italy
| | - Elias S J Arnér
- Division of Biochemistry, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, SE-171 77, Stockholm, Sweden; Department of Selenoprotein Research, National Institute of Oncology, Budapest, Hungary.
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8
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Vučković AM, Venerando R, Tibaldi E, Bosello Travain V, Roveri A, Bordin L, Miotto G, Cozza G, Toppo S, Maiorino M, Ursini F. Aerobic pyruvate metabolism sensitizes cells to ferroptosis primed by GSH depletion. Free Radic Biol Med 2021; 167:45-53. [PMID: 33711415 DOI: 10.1016/j.freeradbiomed.2021.02.045] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/06/2021] [Revised: 02/10/2021] [Accepted: 02/26/2021] [Indexed: 12/22/2022]
Abstract
Ferroptosis is a non-accidental, regulated form of cell death operated by lipid peroxidation under strict control of GPx4 activity. This is consistent with the notion that lipid peroxidation is initiated by radicals produced from decomposition of traces of pre-existing lipid hydroperoxides. The question, therefore, emerges about the formation of these traces of lipid hydroperoxides interacting with Fe2+. In the most realistic option, they are produced by oxygen activated species generated during aerobic metabolism. Screening for metabolic sources of superoxide supporting ferroptosis induced by GSH depletion, we failed to detect, in our cell model, a role of respiratory chain. We observed instead that the pyruvate dehydrogenase complex -as other α keto acid dehydrogenases already known as a major source of superoxide in mitochondria- supports ferroptosis. The opposite effect on ferroptosis by silencing either the E1 or the E3 subunit of the pyruvate dehydrogenase complex pointed out the autoxidation of dihydrolipoamide as the source of superoxide. We finally observed that GSH depletion activates superoxide production, seemingly through the inhibition of the specific kinase that inhibits pyruvate dehydrogenase. In summary, this set of data is compatible with a scenario where the more electrophilic status produced by GSH depletion not only activates ferroptosis by preventing GPx4 activity, but also favors the formation of lipid hydroperoxides. In an attractive perspective of tissue homeostasis, it is the activation of energetic metabolism associated to a decreased nucleophilic tone that, besides supporting energy demanding proliferation, also sensitizes cells to a regulated form of death.
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Affiliation(s)
- Ana-Marija Vučković
- Department of Molecular Medicine, University of Padova, Viale G. Colombo 3, I-35131, Padova, Italy
| | - Rina Venerando
- Department of Molecular Medicine, University of Padova, Viale G. Colombo 3, I-35131, Padova, Italy
| | - Elena Tibaldi
- Department of Molecular Medicine, University of Padova, Viale G. Colombo 3, I-35131, Padova, Italy
| | | | - Antonella Roveri
- Department of Molecular Medicine, University of Padova, Viale G. Colombo 3, I-35131, Padova, Italy
| | - Luciana Bordin
- Department of Molecular Medicine, University of Padova, Viale G. Colombo 3, I-35131, Padova, Italy
| | - Giovanni Miotto
- Department of Molecular Medicine, University of Padova, Viale G. Colombo 3, I-35131, Padova, Italy
| | - Giorgio Cozza
- Department of Molecular Medicine, University of Padova, Viale G. Colombo 3, I-35131, Padova, Italy
| | - Stefano Toppo
- Department of Molecular Medicine, University of Padova, Viale G. Colombo 3, I-35131, Padova, Italy
| | - Matilde Maiorino
- Department of Molecular Medicine, University of Padova, Viale G. Colombo 3, I-35131, Padova, Italy.
| | - Fulvio Ursini
- Department of Molecular Medicine, University of Padova, Viale G. Colombo 3, I-35131, Padova, Italy
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Bosello Travain V, Miotto G, Vučković AM, Cozza G, Roveri A, Toppo S, Ursini F, Venerando R, Zaccarin M, Maiorino M. Lack of glutathione peroxidase-8 in the ER impacts on lipid composition of HeLa cells microsomal membranes. Free Radic Biol Med 2020; 147:80-89. [PMID: 31857233 DOI: 10.1016/j.freeradbiomed.2019.12.010] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/06/2019] [Accepted: 12/09/2019] [Indexed: 01/04/2023]
Abstract
GPx8 is a glutathione peroxidase homolog inserted in the membranes of endoplasmic reticulum (ER), where it seemingly plays a role in controlling redox status by preventing the spill of H2O2. We addressed the impact of GPx8 silencing on the lipidome of microsomal membranes, using stably GPx8-silenced HeLa cells. The two cell lines were clearly separated by Principal Component Analysis (PCA) and Partial Least Square Discriminant analysis (PLS-DA) of lipidome. Considering in detail the individual lipid classes, we observed that unsaturated glycerophospholipids (GPL) decreased, while only in phosphatidylinositols (PI) a substitution of monounsaturated fatty acids (MUFA) for polyunsaturated fatty acids (PUFA) was observed. Among sphingolipids (SL), ceramides (CER) decreased while sphingomyelins (SM) and neutral glycophingolipids (nGSL) increased. Here, in addition, longer chains than in controls in the amide fatty acid were present. The increase up to four folds of the CER (d18:1; c24:0) containing three hexose units, was the most remarkable species increasing in the differential lipidome of siGPx8 cells. Quantitative RT-PCR complied with lipidomic analysis specifically showing an increased expression of: i) acyl-CoA synthetase 5 (ACSL5); ii) CER synthase 2 and 4; iii) CER transporter (CERT); iv) UDP-glucosyl transferase (UDP-GlcT), associated to a decreased expression of UDP-galactosyl transferase (UDP-GalT). A role of the unfolded protein response (UPR) and the spliced form of the transcription factor XBP1 on the transcriptional changes of GPx8 silenced cells was ruled-out. Similarly, also the involvement of Nrf2 and NF-κB. Altogether our results indicate that GPx8-silencing of HeLa yields a membrane depleted by about 24% of polyunsaturated GPL and a corresponding increase of saturated or monounsaturated SM and specific nGSL. This is tentatively interpreted as an adaptive mechanism leading to an increased resistance to radical oxidations. Moreover, the marked shift of fatty acid composition of PI emerges as a possibly relevant issue in respect to the impact of GPx8 on signaling pathways.
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Affiliation(s)
- Valentina Bosello Travain
- Department of Molecular Medicine, University of Padova, Viale G. Colombo, 3, I-35131, Padova, Italy.
| | - Giovanni Miotto
- CRIBI Biotechnology Center, University of Padova, Viale G. Colombo, 3, I-35131, Padova, Italy.
| | - Ana-Marija Vučković
- Department of Molecular Medicine, University of Padova, Viale G. Colombo, 3, I-35131, Padova, Italy.
| | - Giorgio Cozza
- Department of Molecular Medicine, University of Padova, Viale G. Colombo, 3, I-35131, Padova, Italy.
| | - Antonella Roveri
- Department of Molecular Medicine, University of Padova, Viale G. Colombo, 3, I-35131, Padova, Italy.
| | - Stefano Toppo
- CRIBI Biotechnology Center, University of Padova, Viale G. Colombo, 3, I-35131, Padova, Italy.
| | - Fulvio Ursini
- Department of Molecular Medicine, University of Padova, Viale G. Colombo, 3, I-35131, Padova, Italy.
| | - Rina Venerando
- Department of Molecular Medicine, University of Padova, Viale G. Colombo, 3, I-35131, Padova, Italy.
| | - Mattia Zaccarin
- Department of Molecular Medicine, University of Padova, Viale G. Colombo, 3, I-35131, Padova, Italy.
| | - Matilde Maiorino
- Department of Molecular Medicine, University of Padova, Viale G. Colombo, 3, I-35131, Padova, Italy.
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10
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Miotto G, Rossetto M, Di Paolo ML, Orian L, Venerando R, Roveri A, Vučković AM, Bosello Travain V, Zaccarin M, Zennaro L, Maiorino M, Toppo S, Ursini F, Cozza G. Insight into the mechanism of ferroptosis inhibition by ferrostatin-1. Redox Biol 2020; 28:101328. [PMID: 31574461 PMCID: PMC6812032 DOI: 10.1016/j.redox.2019.101328] [Citation(s) in RCA: 344] [Impact Index Per Article: 86.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2019] [Revised: 09/05/2019] [Accepted: 09/15/2019] [Indexed: 01/18/2023] Open
Abstract
Ferroptosis is a form of cell death primed by iron and lipid hydroperoxides and prevented by GPx4. Ferrostatin-1 (fer-1) inhibits ferroptosis much more efficiently than phenolic antioxidants. Previous studies on the antioxidant efficiency of fer-1 adopted kinetic tests where a diazo compound generates the hydroperoxyl radical scavenged by the antioxidant. However, this reaction, accounting for a chain breaking effect, is only minimally useful for the description of the inhibition of ferrous iron and lipid hydroperoxide dependent peroxidation. Scavenging lipid hydroperoxyl radicals, indeed, generates lipid hydroperoxides from which ferrous iron initiates a new peroxidative chain reaction. We show that when fer-1 inhibits peroxidation, initiated by iron and traces of lipid hydroperoxides in liposomes, the pattern of oxidized species produced from traces of pre-existing hydroperoxides is practically identical to that observed following exhaustive peroxidation in the absence of the antioxidant. This supported the notion that the anti-ferroptotic activity of fer-1 is actually due to the scavenging of initiating alkoxyl radicals produced, together with other rearrangement products, by ferrous iron from lipid hydroperoxides. Notably, fer-1 is not consumed while inhibiting iron dependent lipid peroxidation. The emerging concept is that it is ferrous iron itself that reduces fer-1 radical. This was supported by electroanalytical evidence that fer-1 forms a complex with iron and further confirmed in cells by fluorescence of calcein, indicating a decrease of labile iron in the presence of fer-1. The notion of such as pseudo-catalytic cycle of the ferrostatin-iron complex was also investigated by means of quantum mechanics calculations, which confirmed the reduction of an alkoxyl radical model by fer-1 and the reduction of fer-1 radical by ferrous iron. In summary, GPx4 and fer-1 in the presence of ferrous iron, produces, by distinct mechanism, the most relevant anti-ferroptotic effect, i.e the disappearance of initiating lipid hydroperoxides.
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Affiliation(s)
- Giovanni Miotto
- Dept. of Molecular Medicine, University of Padova, V.le G. Colombo, 3, I-35121, Padova, Italy; CRIBI Biotechnology Center, University of Padova, V.le G. Colombo, 3, I-35121, Padova, Italy
| | - Monica Rossetto
- Dept. of Molecular Medicine, University of Padova, V.le G. Colombo, 3, I-35121, Padova, Italy
| | - Maria Luisa Di Paolo
- Dept. of Molecular Medicine, University of Padova, V.le G. Colombo, 3, I-35121, Padova, Italy
| | - Laura Orian
- Dept. of Chemical Sciences, University of Padova, Via Marzolo, 1, I-35131, Padova, Italy
| | - Rina Venerando
- Dept. of Molecular Medicine, University of Padova, V.le G. Colombo, 3, I-35121, Padova, Italy
| | - Antonella Roveri
- Dept. of Molecular Medicine, University of Padova, V.le G. Colombo, 3, I-35121, Padova, Italy
| | - Ana-Marija Vučković
- Dept. of Molecular Medicine, University of Padova, V.le G. Colombo, 3, I-35121, Padova, Italy
| | | | - Mattia Zaccarin
- Dept. of Molecular Medicine, University of Padova, V.le G. Colombo, 3, I-35121, Padova, Italy
| | - Lucio Zennaro
- Dept. of Molecular Medicine, University of Padova, V.le G. Colombo, 3, I-35121, Padova, Italy
| | - Matilde Maiorino
- Dept. of Molecular Medicine, University of Padova, V.le G. Colombo, 3, I-35121, Padova, Italy
| | - Stefano Toppo
- Dept. of Molecular Medicine, University of Padova, V.le G. Colombo, 3, I-35121, Padova, Italy; CRIBI Biotechnology Center, University of Padova, V.le G. Colombo, 3, I-35121, Padova, Italy
| | - Fulvio Ursini
- Dept. of Molecular Medicine, University of Padova, V.le G. Colombo, 3, I-35121, Padova, Italy.
| | - Giorgio Cozza
- Dept. of Molecular Medicine, University of Padova, V.le G. Colombo, 3, I-35121, Padova, Italy.
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11
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Vučković A, Bosello Travain V, Bordin L, Cozza G, Miotto G, Rossetto M, Toppo S, Venerando R, Zaccarin M, Maiorino M, Ursini F, Roveri A. Inactivation of the glutathione peroxidase GPx4 by the ferroptosis‐inducing molecule RSL3 requires the adaptor protein 14‐3‐3ε. FEBS Lett 2019; 594:611-624. [DOI: 10.1002/1873-3468.13631] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2019] [Revised: 09/12/2019] [Accepted: 09/26/2019] [Indexed: 01/17/2023]
Affiliation(s)
| | | | - Luciana Bordin
- Department of Molecular Medicine University of Padova Italy
| | - Giorgio Cozza
- Department of Molecular Medicine University of Padova Italy
| | | | | | - Stefano Toppo
- Department of Molecular Medicine University of Padova Italy
| | - Rina Venerando
- Department of Molecular Medicine University of Padova Italy
| | | | | | - Fulvio Ursini
- Department of Molecular Medicine University of Padova Italy
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12
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Ingold I, Berndt C, Schmitt S, Doll S, Poschmann G, Buday K, Roveri A, Peng X, Porto Freitas F, Seibt T, Mehr L, Aichler M, Walch A, Lamp D, Jastroch M, Miyamoto S, Wurst W, Ursini F, Arnér ES, Fradejas-Villar N, Schweizer U, Zischka H, Friedmann Angeli JP, Conrad M. Selenium Utilization by GPX4 Is Required to Prevent Hydroperoxide-Induced Ferroptosis. Cell 2018; 172:409-422.e21. [DOI: 10.1016/j.cell.2017.11.048] [Citation(s) in RCA: 458] [Impact Index Per Article: 76.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2017] [Revised: 10/16/2017] [Accepted: 11/28/2017] [Indexed: 01/11/2023]
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13
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Andrisani A, Donà G, Sabbadin C, Dall'Acqua S, Tibaldi E, Roveri A, Bosello Travain V, Brunati AM, Ambrosini G, Ragazzi E, Armanini D, Bordin L. Dapsone hydroxylamine-mediated alterations in human red blood cells from endometriotic patients. Gynecol Endocrinol 2017; 33:928-932. [PMID: 28557604 DOI: 10.1080/09513590.2017.1332177] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Endometriosis, an estrogen-dependent chronic gynecological disease in women of reproductive age, is characterized by a systemic inflammation status involving also red blood cells (RBCs). In this study, we evaluated how the protein oxidative status could be involved in the worsening of RBC conditions due to dapsone intake in endometriotic women in potential treatment for skin or infection diseases. Blood samples from two groups of volunteers, control group (CG) and endometriosis patient group (PG), were analyzed for their content of band 3 tyrosine phosphorylation (Tyr-P) and high molecular weight aggregate (HMWA) in membranes, and glutathione (GSH) content and carbonic anhydrase (CA) activity in cytosol. In endometriotic patients, RBC showed the highest level of oxidative-related alterations both in membrane and cytosol. More interestingly, the addition of dapsone hydroxylamine (DDS-NHOH) could induce further increase of both membranes and cytosol markers, with an enhancement of CA activity reaching about 66% of the total cell enzyme amount. In conclusion, in PG the systemic inflammatory status leads to the inability of counteracting adjunctive oxidative stress, with a potential involvement of CA-related pathologies, such as glaucoma. Hence, the importance of the evaluation of therapeutic approaches worsening oxidative imbalance present in PG RBC is underlined.
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Affiliation(s)
- Alessandra Andrisani
- a Department of Women's and Children's Health , University of Padova , Padova , Italy
| | - Gabriella Donà
- b Department of Molecular Medicine - Biological Chemistry , University of Padova , Padova , Italy
| | - Chiara Sabbadin
- c Department of Medicine - Endocrinology , University of Padova , Padova , Italy
| | - Stefano Dall'Acqua
- d Department of Pharmaceutical and Pharmacological Sciences , University of Padova , Padova , Italy
| | - Elena Tibaldi
- b Department of Molecular Medicine - Biological Chemistry , University of Padova , Padova , Italy
| | - Antonella Roveri
- b Department of Molecular Medicine - Biological Chemistry , University of Padova , Padova , Italy
| | | | - Anna Maria Brunati
- b Department of Molecular Medicine - Biological Chemistry , University of Padova , Padova , Italy
| | - Guido Ambrosini
- a Department of Women's and Children's Health , University of Padova , Padova , Italy
| | - Eugenio Ragazzi
- d Department of Pharmaceutical and Pharmacological Sciences , University of Padova , Padova , Italy
| | - Decio Armanini
- c Department of Medicine - Endocrinology , University of Padova , Padova , Italy
| | - Luciana Bordin
- b Department of Molecular Medicine - Biological Chemistry , University of Padova , Padova , Italy
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14
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Cozza G, Rossetto M, Bosello-Travain V, Maiorino M, Roveri A, Toppo S, Zaccarin M, Zennaro L, Ursini F. Glutathione peroxidase 4-catalyzed reduction of lipid hydroperoxides in membranes: The polar head of membrane phospholipids binds the enzyme and addresses the fatty acid hydroperoxide group toward the redox center. Free Radic Biol Med 2017; 112:1-11. [PMID: 28709976 DOI: 10.1016/j.freeradbiomed.2017.07.010] [Citation(s) in RCA: 87] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/01/2017] [Revised: 07/03/2017] [Accepted: 07/06/2017] [Indexed: 12/31/2022]
Abstract
GPx4 is a monomeric glutathione peroxidase, unique in reducing the hydroperoxide group (-OOH) of fatty acids esterified in membrane phospholipids. This reaction inhibits lipid peroxidation and accounts for enzyme's vital role. Here we investigated the interaction of GPx4 with membrane phospholipids. A cationic surface near the GPx4 catalytic center interacts with phospholipid polar heads. Accordingly, SPR analysis indicates cardiolipin as the phospholipid with maximal affinity to GPx4. Consistent with the electrostatic nature of the interaction, KCl increases the KD. Molecular dynamic (MD) simulation shows that a -OOH posed in the core of the membrane as 13 - or 9 -OOH of tetra-linoleoyl cardiolipin or 15 -OOH stearoyl-arachidonoyl-phosphaphatidylcholine moves to the lipid-water interface. Thereby, the -OOH groups are addressed toward the GPx4 redox center. In this pose, however, the catalytic site facing the membrane would be inaccessible to GSH, but the consecutive redox processes facilitate access of GSH, which further primes undocking of the enzyme, because GSH competes for the binding residues implicated in docking. During the final phase of the catalytic cycle, while GSSG is produced, GPx4 is disconnected from the membrane. The observation that GSH depletion in cells induces GPx4 translocation to the membrane, is in agreement with this concept.
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Affiliation(s)
- Giorgio Cozza
- Department of Molecular Medicine, University of Padova, Viale G. Colombo, 3, I-35121 Padova, Italy
| | - Monica Rossetto
- Department of Molecular Medicine, University of Padova, Viale G. Colombo, 3, I-35121 Padova, Italy
| | | | - Matilde Maiorino
- Department of Molecular Medicine, University of Padova, Viale G. Colombo, 3, I-35121 Padova, Italy
| | - Antonella Roveri
- Department of Molecular Medicine, University of Padova, Viale G. Colombo, 3, I-35121 Padova, Italy
| | - Stefano Toppo
- Department of Molecular Medicine, University of Padova, Viale G. Colombo, 3, I-35121 Padova, Italy
| | - Mattia Zaccarin
- Department of Molecular Medicine, University of Padova, Viale G. Colombo, 3, I-35121 Padova, Italy
| | - Lucio Zennaro
- Department of Molecular Medicine, University of Padova, Viale G. Colombo, 3, I-35121 Padova, Italy
| | - Fulvio Ursini
- Department of Molecular Medicine, University of Padova, Viale G. Colombo, 3, I-35121 Padova, Italy.
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15
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Zaccarin M, Bosello-Travain V, Di Paolo ML, Falda M, Maiorino M, Miotto G, Piccolo S, Roveri A, Ursini F, Venerando R, Toppo S. Redox status in a model of cancer stem cells. Arch Biochem Biophys 2016; 617:120-128. [PMID: 27638050 DOI: 10.1016/j.abb.2016.09.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2016] [Revised: 09/09/2016] [Accepted: 09/12/2016] [Indexed: 12/31/2022]
Abstract
Reversible oxidation of Cys residues is a crucial element of redox homeostasis and signaling. According to a popular concept in oxidative stress signaling, the oxidation of targets of signals can only take place following an overwhelming of the cellular antioxidant capacity. This concept, however, ignores the activation of feedback mechanisms possibly leading to a paradoxical effect. In a model of cancer stem cells (CSC), stably overexpressing the TAZ oncogene, we observed that the increased formation of oxidants is associated with a globally more reduced state of proteins. Redox proteomics revealed that several proteins, capable of undergoing reversible redox transitions, are indeed more reduced while just few are more oxidized. Among the proteins more oxidized, G6PDH emerges as both more expressed and activated by oxidation. This accounts for the observed more reduced state of the NADPH/NADP+ couple. The dynamic redox flux generating this apparently paradoxical effect is rationalized in a computational system biology model highlighting the crucial role of G6PDH activity on the rate of redox transitions eventually leading to the reduction of reversible redox switches.
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Affiliation(s)
- Mattia Zaccarin
- Department of Molecular Medicine, University of Padova, Viale G.Colombo 3, 35121 Padova, Italy
| | | | - Maria Luisa Di Paolo
- Department of Molecular Medicine, University of Padova, Viale G.Colombo 3, 35121 Padova, Italy
| | - Marco Falda
- Department of Molecular Medicine, University of Padova, Viale G.Colombo 3, 35121 Padova, Italy
| | - Matilde Maiorino
- Department of Molecular Medicine, University of Padova, Viale G.Colombo 3, 35121 Padova, Italy
| | - Giovanni Miotto
- Department of Molecular Medicine, University of Padova, Viale G.Colombo 3, 35121 Padova, Italy
| | - Stefano Piccolo
- Department of Molecular Medicine, University of Padova, Viale G.Colombo 3, 35121 Padova, Italy
| | - Antonella Roveri
- Department of Molecular Medicine, University of Padova, Viale G.Colombo 3, 35121 Padova, Italy
| | - Fulvio Ursini
- Department of Molecular Medicine, University of Padova, Viale G.Colombo 3, 35121 Padova, Italy
| | - Rina Venerando
- Department of Molecular Medicine, University of Padova, Viale G.Colombo 3, 35121 Padova, Italy
| | - Stefano Toppo
- Department of Molecular Medicine, University of Padova, Viale G.Colombo 3, 35121 Padova, Italy.
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16
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Orian L, Mauri P, Roveri A, Toppo S, Benazzi L, Bosello-Travain V, De Palma A, Maiorino M, Miotto G, Zaccarin M, Polimeno A, Flohé L, Ursini F. Selenocysteine oxidation in glutathione peroxidase catalysis: an MS-supported quantum mechanics study. Free Radic Biol Med 2015; 87:1-14. [PMID: 26163004 DOI: 10.1016/j.freeradbiomed.2015.06.011] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/01/2015] [Revised: 05/18/2015] [Accepted: 06/09/2015] [Indexed: 12/31/2022]
Abstract
Glutathione peroxidases (GPxs) are enzymes working with either selenium or sulfur catalysis. They adopted diverse functions ranging from detoxification of H(2)O(2) to redox signaling and differentiation. The relative stability of the selenoenzymes, however, remained enigmatic in view of the postulated involvement of a highly unstable selenenic acid form during catalysis. Nevertheless, density functional theory calculations obtained with a representative active site model verify the mechanistic concept of GPx catalysis and underscore its efficiency. However, they also allow that the selenenic acid, in the absence of the reducing substrate, reacts with a nitrogen in the active site. MS/MS analysis of oxidized rat GPx4 complies with the predicted structure, an 8-membered ring, in which selenium is bound as selenenylamide to the protein backbone. The intermediate can be re-integrated into the canonical GPx cycle by glutathione, whereas, under denaturing conditions, its selenium moiety undergoes β-cleavage with formation of a dehydro-alanine residue. The selenenylamide bypass prevents destruction of the redox center due to over-oxidation of the selenium or its elimination and likely allows fine-tuning of GPx activity or alternate substrate reactions for regulatory purposes.
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Affiliation(s)
- Laura Orian
- Department of Chemistry, University of Padova, Italy
| | - Pierluigi Mauri
- Institute for Biomedical Technologies, National Research Council, Milano, Italy
| | | | - Stefano Toppo
- Department of Molecular Medicine, University of Padova, Italy
| | - Louise Benazzi
- Institute for Biomedical Technologies, National Research Council, Milano, Italy
| | | | - Antonella De Palma
- Institute for Biomedical Technologies, National Research Council, Milano, Italy
| | | | - Giovanni Miotto
- Department of Molecular Medicine, University of Padova, Italy
| | - Mattia Zaccarin
- Department of Molecular Medicine, University of Padova, Italy
| | | | - Leopold Flohé
- Department of Molecular Medicine, University of Padova, Italy.
| | - Fulvio Ursini
- Department of Molecular Medicine, University of Padova, Italy
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17
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Maiorino M, Bosello-Travain V, Cozza G, Miotto G, Roveri A, Toppo S, Zaccarin M, Ursini F. Understanding mammalian glutathione peroxidase 7 in the light of its homologs. Free Radic Biol Med 2015; 83:352-60. [PMID: 25724691 DOI: 10.1016/j.freeradbiomed.2015.02.017] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/08/2014] [Revised: 02/09/2015] [Accepted: 02/14/2015] [Indexed: 01/24/2023]
Abstract
The glutathione peroxidase homologs (GPxs) efficiently reduce hydroperoxides using electrons from glutathione (GSH), thioredoxin (Trx), or protein disulfide isomerase (PDI). Trx is preferentially used by the GPxs of the majority of bacteria, invertebrates, plants, and fungi. GSH or PDI, instead, is preferentially used by vertebrate GPxs that operate by Sec or Cys catalysis, respectively. Mammalian GPx7 and GPx8 are unique homologs that contain a peroxidatic Cys (CP). Being reduced by PDI and located within the endoplasmic reticulum (ER), these enzymes have been involved in oxidative protein folding. Kinetic analysis indicates that oxidation of PDI by recombinant GPx7 occurs at a much faster rate than that of GSH. Nonetheless, activity measurement suggests that, at physiological concentrations, a competition between these two substrates takes place, with the rate of PDI oxidation by GPx7 controlled by the concentration of GSH, whereas the GSSG produced in the competing reaction contributes to the ER redox buffer. A mechanism has been proposed for GPx7 involving two Cys residues, in which an intramolecular disulfide of the CP is formed with an alleged resolving Cys (CR) located in the strongly conserved FPCNQ motif (C86 in humans), a noncanonical position in GPxs. Kinetic measurements and comparison with the other thiol peroxidases containing a functional CR suggest that a resolving function of C86 in the catalytic cycle is very unlikely. We propose that GPx7 is catalytically active as a 1-Cys-GPx, in which CP both reduces H2O2 and oxidizes PDI, and that the CP-C86 disulfide has instead the role of stabilizing the oxidized peroxidase in the absence of the reducing substrate.
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Affiliation(s)
- Matilde Maiorino
- Department of Molecular Medicine and University of Padova, I-35121 Padova, Italy.
| | | | - Giorgio Cozza
- Department of Biomedical Sciences, University of Padova, I-35121 Padova, Italy
| | - Giovanni Miotto
- Department of Molecular Medicine and University of Padova, I-35121 Padova, Italy
| | - Antonella Roveri
- Department of Molecular Medicine and University of Padova, I-35121 Padova, Italy
| | - Stefano Toppo
- Department of Molecular Medicine and University of Padova, I-35121 Padova, Italy
| | - Mattia Zaccarin
- Department of Molecular Medicine and University of Padova, I-35121 Padova, Italy
| | - Fulvio Ursini
- Department of Molecular Medicine and University of Padova, I-35121 Padova, Italy
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18
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Ingold I, Aichler M, Yefremova E, Roveri A, Buday K, Doll S, Tasdemir A, Hoffard N, Wurst W, Walch A, Ursini F, Friedmann Angeli JP, Conrad M. Expression of a Catalytically Inactive Mutant Form of Glutathione Peroxidase 4 (Gpx4) Confers a Dominant-negative Effect in Male Fertility. J Biol Chem 2015; 290:14668-78. [PMID: 25922076 DOI: 10.1074/jbc.m115.656363] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2015] [Indexed: 01/20/2023] Open
Abstract
The selenoenzyme Gpx4 is essential for early embryogenesis and cell viability for its unique function to prevent phospholipid oxidation. Recently, the cytosolic form of Gpx4 was identified as an upstream regulator of a novel form of non-apoptotic cell death, called ferroptosis, whereas the mitochondrial isoform of Gpx4 was previously shown to be crucial for male fertility. Here, we generated and analyzed mice with a targeted mutation of the active site selenocysteine of Gpx4 (Gpx4_U46S). Mice homozygous for Gpx4_U46S died at the same embryonic stage (E7.5) as Gpx4(-/-) embryos as expected. Surprisingly, male mice heterozygous for Gpx4_U46S presented subfertility. Subfertility was manifested in a reduced number of litters from heterozygous breeding and an impairment of spermatozoa to fertilize oocytes in vitro. Morphologically, sperm isolated from heterozygous Gpx4_U46S mice revealed many structural abnormalities particularly in the spermatozoa midpiece due to improper oxidation and polymerization of sperm capsular proteins and malformation of the mitochondrial capsule surrounding and stabilizing sperm mitochondria. These findings are reminiscent of sperm isolated from selenium-deprived rodents or from mice specifically lacking mitochondrial Gpx4. Due to a strongly facilitated incorporation of Ser in the polypeptide chain as compared with selenocysteine at the UGA codon, expression of the catalytically inactive Gpx4_U46S was found to be strongly increased. Because the stability of the mitochondrial capsule of mature spermatozoa depends on the moonlighting function of Gpx4 both as an enzyme oxidizing capsular protein thiols and as a structural protein, tightly controlled expression of functional Gpx4 emerges as a key for full male fertility.
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Affiliation(s)
- Irina Ingold
- From the Helmholtz Zentrum München, German Research Center for Environmental Health, Institute of Developmental Genetics, Ingolstädter Landstrassse 1, 85764 Neuherberg, Germany
| | - Michaela Aichler
- Research Unit Analytical Pathology, Helmholtz Zentrum München, Ingolstädter Landstrasse 1, 85764 Neuherberg, Germany
| | - Elena Yefremova
- From the Helmholtz Zentrum München, German Research Center for Environmental Health, Institute of Developmental Genetics, Ingolstädter Landstrassse 1, 85764 Neuherberg, Germany
| | - Antonella Roveri
- Department of Molecular Medicine, University of Padova, 35121 Padova, Italy
| | - Katalin Buday
- From the Helmholtz Zentrum München, German Research Center for Environmental Health, Institute of Developmental Genetics, Ingolstädter Landstrassse 1, 85764 Neuherberg, Germany
| | - Sebastian Doll
- From the Helmholtz Zentrum München, German Research Center for Environmental Health, Institute of Developmental Genetics, Ingolstädter Landstrassse 1, 85764 Neuherberg, Germany
| | - Adrianne Tasdemir
- From the Helmholtz Zentrum München, German Research Center for Environmental Health, Institute of Developmental Genetics, Ingolstädter Landstrassse 1, 85764 Neuherberg, Germany
| | - Nils Hoffard
- From the Helmholtz Zentrum München, German Research Center for Environmental Health, Institute of Developmental Genetics, Ingolstädter Landstrassse 1, 85764 Neuherberg, Germany
| | - Wolfgang Wurst
- From the Helmholtz Zentrum München, German Research Center for Environmental Health, Institute of Developmental Genetics, Ingolstädter Landstrassse 1, 85764 Neuherberg, Germany, Deutsches Zentrum für Neurodegenerative Erkrankungen e. V. (DZNE) Standort München, Schillerstrasse 44, 80336 Munich, Germany, Munich Cluster for Systems Neurology (SyNergy) Adolf-Butenandt-Institut Ludwig-Maximilians-Universität München, Schillerstrasse 44, 80336 Munich, Germany, and Technische Universität München-Weihenstephan, Lehrstuhl für Entwicklungsgenetik c/o Helmholtz Zentrum München, Ingolstädter Landstrasse 1, 85764 Neuherberg, Germany
| | - Axel Walch
- Research Unit Analytical Pathology, Helmholtz Zentrum München, Ingolstädter Landstrasse 1, 85764 Neuherberg, Germany
| | - Fulvio Ursini
- Department of Molecular Medicine, University of Padova, 35121 Padova, Italy
| | - José Pedro Friedmann Angeli
- From the Helmholtz Zentrum München, German Research Center for Environmental Health, Institute of Developmental Genetics, Ingolstädter Landstrassse 1, 85764 Neuherberg, Germany
| | - Marcus Conrad
- From the Helmholtz Zentrum München, German Research Center for Environmental Health, Institute of Developmental Genetics, Ingolstädter Landstrassse 1, 85764 Neuherberg, Germany,
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Bosello-Travain V, Forman HJ, Roveri A, Toppo S, Ursini F, Venerando R, Warnecke C, Zaccarin M, Maiorino M. Glutathione peroxidase 8 is transcriptionally regulated by HIFα and modulates growth factor signaling in HeLa cells. Free Radic Biol Med 2015; 81:58-68. [PMID: 25557012 DOI: 10.1016/j.freeradbiomed.2014.12.020] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/10/2014] [Revised: 11/25/2014] [Accepted: 12/21/2014] [Indexed: 01/06/2023]
Abstract
GPx8 is a mammalian Cys-glutathione peroxidase of the endoplasmic reticulum membrane, involved in protein folding. Its regulation is mostly unknown. We addressed both the functionality of two hypoxia-response elements (HREs) within the promoter, GPx8 HRE1 and GPx8 HRE2, and the GPx8 physiological role. In HeLa cells, treatment with HIFα stabilizers, such as diethyl succinate (DES) or 2-2'-bipyridyl (BP), induces GPx8 expression at both mRNA and protein level. Luciferase activity of pGL3(GPx8wt), containing a fragment of the GPx8 promoter including the two HREs, is also induced by DES/BP or by overexpressing either individual HIFα subunit. Mutating GPx8 HRE1 within pGL3(GPx8wt) resulted in a significantly higher inhibition of luciferase activity than mutating GPx8 HRE2. Electrophoretic mobility-shift assay showed that both HREs exhibit enhanced binding to a nuclear extract from DES/BP-treated cells, with stronger binding by GPx8 HRE1. In DES-treated cells transfected with pGL3(GPx8wt) or mutants thereof, silencing of HIF2α, but not HIF1α, abolishes luciferase activity. Thus GPx8 is a novel HIF target preferentially responding to HIF2α binding at its two novel functional GPx8 HREs, with GPx8 HRE1 playing the major role. Fibroblast growth factor (FGF) treatment increases GPx8 mRNA expression, and reporter gene experiments indicate that induction occurs via HIF. Comparing the effects of depleting GPx8 on the downstream effectors of FGF or insulin signaling revealed that absence of GPx8 results in a 16- or 12-fold increase in phosphorylated ERK1/2 by FGF or insulin treatment, respectively. Furthermore, in GPx8-depleted cells, phosphorylation of AKT by insulin treatment increases 2.5-fold. We suggest that induction of GPx8 expression by HIF slows down proliferative signaling during hypoxia and/or growth stimulation through receptor tyrosine kinases.
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Affiliation(s)
| | - Henry J Forman
- Life and Environmental Sciences, University of California at Merced, Merced, CA 95344, USA
| | - Antonella Roveri
- Department of Molecular Medicine, University of Padova, I-35121 Padova, Italy
| | - Stefano Toppo
- Department of Molecular Medicine, University of Padova, I-35121 Padova, Italy
| | - Fulvio Ursini
- Department of Molecular Medicine, University of Padova, I-35121 Padova, Italy
| | - Rina Venerando
- Department of Molecular Medicine, University of Padova, I-35121 Padova, Italy
| | - Christina Warnecke
- Department of Nephrology and Hypertension, Translational Research Center, University Hospital Erlangen-Nürnberg, Erlangen, Germany
| | - Mattia Zaccarin
- Department of Molecular Medicine, University of Padova, I-35121 Padova, Italy
| | - Matilde Maiorino
- Department of Molecular Medicine, University of Padova, I-35121 Padova, Italy.
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Ceccherelli F, Marino E, Caliendo A, Dezzoni R, Roveri A, Gagliardi G. 3,5,11 needles: looking for the perfect number of needles--a randomized and controlled study. ACUPUNCTURE ELECTRO 2015; 39:241-58. [PMID: 25693307 DOI: 10.3727/036012914x14109544776097] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Acupuncture has been successfully used in myofascial pain syndromes. However, the number of needles used, i.e. the "dose" of acupuncture stimulation, to obtain the best antinociceptive efficacy, is still a matter of debate. The question was addressed comparing the clinical efficacy of 3 different therapeutic schemes, mainly characterized by different numbers of needles used on 90 patients affected by a painful cervical myofascial syndrome. Patients were divided into 3 groups; the first group of 30 patients was treated with 11 needles, the second group of 30 patients was treated with 5 needles and the third group of 30 patients was treated with 3 needles. Each group underwent eight cycles of somatic acupuncture. In each session and in each group, all needles were stimulated until the pain tolerance threshold was reached; "pain tolerance is the amount of pain a person can handle without breaking down, either physically or emotionally". Pain intensity was evaluated before therapy, immediately after, and at 1 and 3 months follow-up by means of both the Mc Gill Pain Questionnaire and the Visual Analogue Scale (VAS). Pain and the repercussion of pain on the patient's quality of life (DOPE- Descriptors Of Pain Effects) were also measured using a test we developed, administered at each session. In all groups, needles were inserted superficially, except for the two most painful trigger points that were deeply inserted. All groups, independently from the number of needles used, obtained a good and significant therapeutic effect without clinically relevant differences among groups. For this pathology and patients of this kind, the number of needles, 3 or 5 or 11, seems not to be an important variable in determining the therapeutic effect.
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21
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Moscatiello R, Zaccarin M, Ercolin F, Damiani E, Squartini A, Roveri A, Navazio L. Identification of ferredoxin II as a major calcium binding protein in the nitrogen-fixing symbiotic bacterium Mesorhizobium loti. BMC Microbiol 2015; 15:16. [PMID: 25648224 PMCID: PMC4322793 DOI: 10.1186/s12866-015-0352-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2014] [Accepted: 01/16/2015] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Legumes establish with rhizobial bacteria a nitrogen-fixing symbiosis which is of the utmost importance for both plant nutrition and a sustainable agriculture. Calcium is known to act as a key intracellular messenger in the perception of symbiotic signals by both the host plant and the microbial partner. Regulation of intracellular free Ca(2+) concentration, which is a fundamental prerequisite for any Ca(2+)-based signalling system, is accomplished by complex mechanisms including Ca(2+) binding proteins acting as Ca(2+) buffers. In this work we investigated the occurrence of Ca(2+) binding proteins in Mesorhizobium loti, the specific symbiotic partner of the model legume Lotus japonicus. RESULTS A soluble, low molecular weight protein was found to share several biochemical features with the eukaryotic Ca(2+)-binding proteins calsequestrin and calreticulin, such as Stains-all blue staining on SDS-PAGE, an acidic isoelectric point and a Ca(2+)-dependent shift of electrophoretic mobility. The protein was purified to homogeneity by an ammonium sulfate precipitation procedure followed by anion-exchange chromatography on DEAE-Cellulose and electroendosmotic preparative electrophoresis. The Ca(2+) binding ability of the M. loti protein was demonstrated by (45)Ca(2+)-overlay assays. ESI-Q-TOF MS/MS analyses of the peptides generated after digestion with either trypsin or endoproteinase AspN identified the rhizobial protein as ferredoxin II and confirmed the presence of Ca(2+) adducts. CONCLUSIONS The present data indicate that ferredoxin II is a major Ca(2+) binding protein in M. loti that may participate in Ca(2+) homeostasis and suggest an evolutionarily ancient origin for protein-based Ca(2+) regulatory systems.
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Affiliation(s)
- Roberto Moscatiello
- Department of Biology, University of Padova, Via U. Bassi 58/B, 35131, Padova, Italy.
| | - Mattia Zaccarin
- Department of Molecular Medicine, University of Padova, Viale G. Colombo 3, 35131, Padova, Italy.
| | - Flavia Ercolin
- Department of Biology, University of Padova, Via U. Bassi 58/B, 35131, Padova, Italy.
| | - Ernesto Damiani
- Department of Biomedical Sciences, University of Padova, Viale G. Colombo 3, 35131, Padova, Italy.
| | - Andrea Squartini
- Department of Agronomy, Food, Natural Resources, Animals and Environment, DAFNAE, University of Padova, Viale dell'Università 16, 35020, Legnaro, Padova, Italy.
| | - Antonella Roveri
- Department of Molecular Medicine, University of Padova, Viale G. Colombo 3, 35131, Padova, Italy.
| | - Lorella Navazio
- Department of Biology, University of Padova, Via U. Bassi 58/B, 35131, Padova, Italy.
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Roveri A, Zaccarin M, Pagetta A, Tramentozzi E, Finotti P. Proteomic Investigation on Grp94-IgG Complexes Circulating in Plasma of Type 1 Diabetic Subjects. J Diabetes Res 2015; 2015:815839. [PMID: 26167512 PMCID: PMC4475746 DOI: 10.1155/2015/815839] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/04/2015] [Accepted: 05/21/2015] [Indexed: 12/26/2022] Open
Abstract
The glucose-regulated protein94 (Grp94) has been found in complexes with IgG in plasma of Type 1 (T1) diabetic subjects; however, the pathogenetic meaning of Grp94-IgG complexes has not yet been elucidated. To shed light on the nature and structure of these complexes in vivo, we conducted a proteomic analysis on plasma of both T1 diabetic subjects and healthy control subjects. IgG purified from plasma was submitted to 2D PAGE followed by Western blotting and mass analysis. Grp94 was detected in plasma of all diabetic but not control subjects and found linked with its N-terminus to the IgG heavy chain. Mass analysis of heavy chain of IgG that binds Grp94 also in vitro, forming stable complexes with characteristics similar to those of native ones, permitted identifying CH2 and CH3 regions as those involved in binding Grp94. At the electron microscopy, IgG from diabetic plasma appeared as fibrils of various lengthes and dimensions, suggestive of elevated aggregating tendency conferred to IgG by Grp94. The nonimmune nature of complexes turned out to be responsible for the particular stability and structure adopted by complexes in plasma of diabetic subjects. Results are of relevance to understanding the pathogenetic mechanisms underlying diabetes and its complications.
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Affiliation(s)
- Antonella Roveri
- Department of Molecular Medicine, Section of Biological Chemistry, University of Padua, Via G. Colombo 3, 35131 Padua, Italy
| | - Mattia Zaccarin
- Department of Molecular Medicine, Section of Biological Chemistry, University of Padua, Via G. Colombo 3, 35131 Padua, Italy
| | - Andrea Pagetta
- Department of Pharmaceutical and Pharmacological Sciences, University of Padua, Largo E. Meneghetti 2, 35131 Padua, Italy
| | - Elisa Tramentozzi
- Department of Pharmaceutical and Pharmacological Sciences, University of Padua, Largo E. Meneghetti 2, 35131 Padua, Italy
| | - Paola Finotti
- Department of Pharmaceutical and Pharmacological Sciences, University of Padua, Largo E. Meneghetti 2, 35131 Padua, Italy
- *Paola Finotti:
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Zaccarin M, Falda M, Roveri A, Bosello-Travain V, Bordin L, Maiorino M, Ursini F, Toppo S. Quantitative label-free redox proteomics of reversible cysteine oxidation in red blood cell membranes. Free Radic Biol Med 2014; 71:90-98. [PMID: 24642086 DOI: 10.1016/j.freeradbiomed.2014.03.013] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/22/2013] [Revised: 03/01/2014] [Accepted: 03/04/2014] [Indexed: 01/06/2023]
Abstract
Reversible oxidation of cysteine residues is a relevant posttranslational modification of proteins. However, the low activation energy and transitory nature of the redox switch and the intrinsic complexity of the analysis render quite challenging the aim of a rigorous high-throughput screening of the redox status of redox-sensitive cysteine residues. We describe here a quantitative workflow for redox proteomics, where the ratio between the oxidized forms of proteins in the control vs treated samples is determined by a robust label-free approach. We critically present the convenience of the procedure by specifically addressing the following aspects: (i) the accurate ratio, calculated from the whole set of identified peptides rather than just isotope-tagged fragments; (ii) the application of a robust analytical pipeline to frame the most consistent data averaged over the biological variability; (iii) the relevance of using stringent criteria of analysis, even at the cost of losing potentially interesting but statistically uncertain data. The pipeline has been assessed on red blood cell membrane challenged with diamide as a model of a mild oxidative condition. The cluster of identified proteins encompassed components of the cytoskeleton more oxidized. Indirectly, our analysis confirmed the previous observation that oxidized hemoglobin binds to membranes while oxidized peroxiredoxin 2 loses affinity.
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Affiliation(s)
- Mattia Zaccarin
- Department of Molecular Medicine, via A. Gabelli, 63, I-35121 Padova, Italy
| | - Marco Falda
- Department of Molecular Medicine, via A. Gabelli, 63, I-35121 Padova, Italy
| | - Antonella Roveri
- Department of Molecular Medicine, via A. Gabelli, 63, I-35121 Padova, Italy
| | | | - Luciana Bordin
- Department of Molecular Medicine, via A. Gabelli, 63, I-35121 Padova, Italy
| | - Matilde Maiorino
- Department of Molecular Medicine, via A. Gabelli, 63, I-35121 Padova, Italy
| | - Fulvio Ursini
- Department of Molecular Medicine, via A. Gabelli, 63, I-35121 Padova, Italy
| | - Stefano Toppo
- Department of Molecular Medicine, via A. Gabelli, 63, I-35121 Padova, Italy.
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Ceccherelli F, Lovato A, Piana E, Gagliardi G, Roveri A. Somatic acupuncture versus ear acupuncture in migraine therapy: a randomized, controlled, blind study. ACUPUNCTURE ELECTRO 2013; 37:277-93. [PMID: 23409612 DOI: 10.3727/036012912x13831831256375] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
This study compares the clinical effectiveness of somatic and ear acupuncture for treatment of migraine without aura. 35 patients were divided into 2 groups, one receiving somatic and the other ear acupuncture. Both groups were treated once a week for 8 weeks and needles were stimulated manually. The severity of pain was evaluated with the Migraine Index and the visual analogue of Scott-Huskisson; other 2 tests were used to monitor the pain threshold and Zung's Self-rating Depression Scale was applied to assess variations in patients' mood. These tests were performed before the beginning and at the end of treatment and, for the follow up, after 1, 3 and 6 months from the end of therapy. On the basis of the migraine index, pain at the end of therapy was significantly lower than before the treatment, being residual pain 54.83% and 63.43%, respectively for somatic and ear acupuncture. Apparently, the 2 treatments were equally effective, as no significant difference could be assessed. On the contrary, a significant difference between the 2 groups was clear during the follow up: in fact, after 6 months residual pain was 16.80% and 48.83% for somatic and ear acupuncture, respectively (p=0.038). These results were confirmed by the Visual Analogue Scale (VAS) test and by the evaluation of pain threshold. It is noteworthy that also Zung's depression test showed a significant decrease of score was present in both groups, at all the times investigated with no difference between the two treatments. These results, though preliminary, are quite promising in supporting the effectiveness of ear acupuncture for treatment of migraine without aura.
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Affiliation(s)
- Francesco Ceccherelli
- Department of Pharmacology and Anesthesiology, University of Padova, A.I.R.A.S., Padova, Italy.
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25
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D’Aguanno S, D’Alessandro A, Pieroni L, Roveri A, Zaccarin M, Marzano V, Canio MD, Bernardini S, Federici G, Urbani A. New Insights into Neuroblastoma Cisplatin Resistance: A Comparative Proteomic and Meta-Mining Investigation. J Proteome Res 2010; 10:416-28. [DOI: 10.1021/pr100457n] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Simona D’Aguanno
- Department of Internal Medicine, University of Rome Tor Vergata, Rome, Italy, S. Lucia Foundation - IRCCS, Rome, Italy, and Departement of Biological Chemistry, University of Padova, Padova, Italy
| | - Annamaria D’Alessandro
- Department of Internal Medicine, University of Rome Tor Vergata, Rome, Italy, S. Lucia Foundation - IRCCS, Rome, Italy, and Departement of Biological Chemistry, University of Padova, Padova, Italy
| | - Luisa Pieroni
- Department of Internal Medicine, University of Rome Tor Vergata, Rome, Italy, S. Lucia Foundation - IRCCS, Rome, Italy, and Departement of Biological Chemistry, University of Padova, Padova, Italy
| | - Antonella Roveri
- Department of Internal Medicine, University of Rome Tor Vergata, Rome, Italy, S. Lucia Foundation - IRCCS, Rome, Italy, and Departement of Biological Chemistry, University of Padova, Padova, Italy
| | - Mattia Zaccarin
- Department of Internal Medicine, University of Rome Tor Vergata, Rome, Italy, S. Lucia Foundation - IRCCS, Rome, Italy, and Departement of Biological Chemistry, University of Padova, Padova, Italy
| | - Valeria Marzano
- Department of Internal Medicine, University of Rome Tor Vergata, Rome, Italy, S. Lucia Foundation - IRCCS, Rome, Italy, and Departement of Biological Chemistry, University of Padova, Padova, Italy
| | - Michele De Canio
- Department of Internal Medicine, University of Rome Tor Vergata, Rome, Italy, S. Lucia Foundation - IRCCS, Rome, Italy, and Departement of Biological Chemistry, University of Padova, Padova, Italy
| | - Sergio Bernardini
- Department of Internal Medicine, University of Rome Tor Vergata, Rome, Italy, S. Lucia Foundation - IRCCS, Rome, Italy, and Departement of Biological Chemistry, University of Padova, Padova, Italy
| | - Giorgio Federici
- Department of Internal Medicine, University of Rome Tor Vergata, Rome, Italy, S. Lucia Foundation - IRCCS, Rome, Italy, and Departement of Biological Chemistry, University of Padova, Padova, Italy
| | - Andrea Urbani
- Department of Internal Medicine, University of Rome Tor Vergata, Rome, Italy, S. Lucia Foundation - IRCCS, Rome, Italy, and Departement of Biological Chemistry, University of Padova, Padova, Italy
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26
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De Palma A, Roveri A, Zaccarin M, Benazzi L, Daminelli S, Pantano G, Buttarello M, Ursini F, Gion M, Mauri PL. Extraction methods of red blood cell membrane proteins for Multidimensional Protein Identification Technology (MudPIT) analysis. J Chromatogr A 2010; 1217:5328-36. [PMID: 20621298 DOI: 10.1016/j.chroma.2010.06.045] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2010] [Accepted: 06/16/2010] [Indexed: 10/19/2022]
Abstract
Since red blood cells (RBCs) lack nuclei and organelles, cell membrane is their main load-bearing component and, according to a dynamic interaction with the cytoskeleton compartment, plays a pivotal role in their functioning. Even if erythrocyte membranes are available in large quantities, the low abundance and the hydrophobic nature of cell membrane proteins complicate their purification and detection by conventional 2D gel-based proteomic approaches. So, in order to increase the efficiency of RBC membrane proteome identification, here we took advantage of a simple and reproducible membrane sub-fractionation method coupled to Multidimensional Protein Identification Technology (MudPIT). In addition, the adoption of a stringent RBC filtration strategy from the whole blood, permitted to remove exhaustively contaminants, such as platelets and white blood cells, and to identify a total of 275 proteins in the three RBC membrane fractions collected and analysed. Finally, by means of software for the elaboration of the great quantity of data obtained and programs for statistical analysis and protein classification, it was possible to determine the validity of the entire system workflow and to assign the proper sub-cellular localization and function for the greatest number of the identified proteins.
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Affiliation(s)
- Antonella De Palma
- Proteomics and Metabolomics Unit, Institute for Biomedical Technologies-CNR, Via Fratelli Cervi 93, I-20090 Segrate, Milan, Italy
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27
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Schneider M, Forster H, Boersma A, Seiler A, Wehnes H, Sinowatz F, Neumüller C, Deutsch MJ, Walch A, Angelis MH, Wurst W, Ursini F, Roveri A, Maleszewski M, Maiorino M, Conrad M. Mitochondrial glutathione peroxidase 4 disruption causes male infertility. FASEB J 2009; 23:3233-42. [DOI: 10.1096/fj.09-132795] [Citation(s) in RCA: 209] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Affiliation(s)
- Manuela Schneider
- Institute of Clinical Molecular Biology and Tumor Genetics German Research Center for Environmental Health Neuherberg Germany
- Walter‐Brendel‐Centre for Experimental Medicine Ludwig‐Maximilians‐University of Munich Marchioninistr. 15 D‐81377 Munich Germany
| | - Heidi Forster
- Institute of Clinical Molecular Biology and Tumor Genetics German Research Center for Environmental Health Neuherberg Germany
| | - Auke Boersma
- Institute of Experimental Genetics German Research Center for Environmental Health Neuherberg Germany
| | - Alexander Seiler
- Institute of Clinical Molecular Biology and Tumor Genetics German Research Center for Environmental Health Neuherberg Germany
| | - Helga Wehnes
- Institute of Pathology German Research Center for Environmental Health Neuherberg Germany
| | - Fred Sinowatz
- Department of Veterinary Anatomy II Ludwig‐Maximilians‐University of Munich Munich Germany
| | - Christine Neumüller
- Department of Veterinary Anatomy II Ludwig‐Maximilians‐University of Munich Munich Germany
| | - Manuel J. Deutsch
- Department of Gene Vectors German Research Center for Environmental Health Neuherberg Germany
| | - Axel Walch
- Institute of Pathology German Research Center for Environmental Health Neuherberg Germany
| | - Martin Hrabe Angelis
- Institute of Experimental Genetics German Research Center for Environmental Health Neuherberg Germany
| | - Wolfgang Wurst
- Institute of Developmental Genetics Helmholtz Zentrum München German Research Center for Environmental Health Neuherberg Germany
| | - Fulvio Ursini
- Department of Biological Chemistry University of Padua Padova Italy
| | - Antonella Roveri
- Department of Biological Chemistry University of Padua Padova Italy
| | - Marek Maleszewski
- Department of Embryology Institute of Zoology University of Warsaw Warsaw Poland
| | - Matilde Maiorino
- Department of Biological Chemistry University of Padua Padova Italy
| | - Marcus Conrad
- Institute of Clinical Molecular Biology and Tumor Genetics German Research Center for Environmental Health Neuherberg Germany
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Abstract
In GPxs, the redox-active Se or S, is at hydrogen bonding distance from Gln and Trp residues that contribute to catalysis. From sequence homology of >400 sequences and modeling of the DmGPx as a paradigm, Asn136 emerged as a fourth essential component of the active site. Mutational substitution of Asn136 by His, Ala, or Asp results in a dramatic decline of specific activity. Kinetic analysis indicates that k(+1), the rate constant for the oxidation of the enzyme, decreases by two to three orders of magnitude, whereas the reductive steps characterized by k'(+2) are less affected. Accordingly, MS/MS analysis shows that in Asn136 mutants, the peroxidatic Cys45 stays largely reduced also in the presence of a hydroperoxide, whereas in the wild-type enzyme, it is oxidized, forming a disulfide with the resolving Cys. Computational calculation of pK(a) values indicates that the residues facing the catalytic thiol, Asn136, Gln80, and, to a lesser extent Trp135, contribute to the dissociation of the thiol group, Asn136 being most relevant. These data disclose that the catalytic site of GPxs has to be redrawn as a tetrad, including Asn136, and suggest a mechanism accounting for the extraordinary catalytic efficiency of GPxs.
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29
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Roveri A, Vitale MP, Serain E, Zaccarin M, Mauri P, Di Silvestre D, De Palma A, Gion M, Toppo S, Maiorino M, Ursini F. Differential liquid phase proteomic analysis of the effect of selenium supplementation in LNCaP cells. J Chromatogr B Analyt Technol Biomed Life Sci 2008; 865:63-73. [PMID: 18329347 DOI: 10.1016/j.jchromb.2008.02.010] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2007] [Revised: 02/05/2008] [Accepted: 02/17/2008] [Indexed: 11/28/2022]
Abstract
The effect of 100 nM sodium selenite supplementation was studied on LNCaP cells by a proteomic approach, on ProteomeLab PF 2D platform. Proteins were separated by liquid phase bi-dimensional chromatography and analyzed by pair-wise alignment of peaks to detect those differentially expressed. Differential expression threshold was set at a twice difference level and proteins matching this criterion were identified by MALDI-TOF and confirmed by ESI-ion trap MS/MS. Not all differentially expressed proteins found by PF 2D could be identified by MS analysis, the sensitivity of which emerging as the limiting factor. Thus, only the most abundant proteins, differently expressed following selenium supplementation, were identified. We positively showed an increase of expression of thioredoxin reductase 1, enolase 1, phosphoglycerate mutase 1, glyceraldehyde-3-phosphate dehydrogenase, heterogeneous nuclear ribonucleoprotein A2/B1, isoform A2, Ras-GTPase-activating protein SH3-domain-binding protein and Keratin 18 and a decrease of expression of peroxiredoxin 1 and heat shock protein 70, protein 8, isoform 1. Results are consistent, at least in part, with the less oxidant environment brought about by the synthesis of Se-dependent peroxidases, keeping low the steady-state concentration of hydrogen peroxide.
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Affiliation(s)
- Antonella Roveri
- Department of Biological Chemistry, University of Padova, I-35131 Padova, Italy
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Ceccherelli F, Gagliardi G, Casale R, Roveri A, Ori C. THE ROLE OF THE INTENSITY OF LOW FREQUENCY ELECTROACUPUNCTURE STIMULATION ON THE MODULATION OF CAPSAICIN-INDUCED EDEMA IN THE RAT PAW. A BLIND CONTROLLED STUDY. ACUPUNCTURE ELECTRO 2008; 33:157-67. [DOI: 10.3727/036012908803861113] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Affiliation(s)
- Francesco Ceccherelli
- Research Professor of Anesthesiology and Intensive Care, Department of Pharmacology and Anesthesiology, University of Padova; Head of Pain Service and Palliative Care Unit of I.0.V.(Istituto Oncologico Veneto)- IRCCS; A.I.R.A.S. Padova,
Italy
| | - Giuseppe Gagliardi
- Department of Pharmacology and Anesthesiology, University of Padova; I.O.V.(lstituto Oncologico Veneto)- IRCCS; A.I.R.A.S. - Padova, Italy
| | - Roberto Casale
- Head of Neurorehabilitation Service of the Rehabilitation Center of Montescano, Maugeri Foundation, IRCCS, Pavia, Italy
| | - Antonella Roveri
- Department of Biologica Chemistry, University of Padova, A.I.R.A.S. - Padova. Italy
| | - Carlo Ori
- Full Professor of Anestehesiology and Intensive Care, Department of Pharmacology and Anesthesiology, University of Padova. Italy
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Vitale M, Roveri A, Zaccarin M, Serain E, Rigobello M, Bindoli A, Marzano C, Gandin V, Ursini F, Gion M. P45 Identification of proteins associated with cisplatin resistance in ovarian cancer by two proteomic approaches. EJC Suppl 2007. [DOI: 10.1016/s1359-6349(08)70095-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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Maiorino M, Ursini F, Bosello V, Toppo S, Tosatto SCE, Mauri P, Becker K, Roveri A, Bulato C, Benazzi L, De Palma A, Flohé L. The Thioredoxin Specificity of Drosophila GPx: A Paradigm for a Peroxiredoxin-like Mechanism of many Glutathione Peroxidases. J Mol Biol 2007; 365:1033-46. [PMID: 17098255 DOI: 10.1016/j.jmb.2006.10.033] [Citation(s) in RCA: 90] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2006] [Revised: 10/09/2006] [Accepted: 10/10/2006] [Indexed: 11/27/2022]
Abstract
Some members of the glutathione peroxidase (GPx) family have been reported to accept thioredoxin as reducing substrate. However, the selenocysteine-containing ones oxidise thioredoxin (Trx), if at all, at extremely slow rates. In contrast, the Cys homolog of Drosophila melanogaster exhibits a clear preference for Trx, the net forward rate constant, k'(+2), for reduction by Trx being 1.5x10(6) M(-1) s(-1), but only 5.4 M(-1) s(-1) for glutathione. Like other CysGPxs with thioredoxin peroxidase activity, Drosophila melanogaster (Dm)GPx oxidized by H(2)O(2) contained an intra-molecular disulfide bridge between the active-site cysteine (C45; C(P)) and C91. Site-directed mutagenesis of C91 in DmGPx abrogated Trx peroxidase activity, but increased the rate constant for glutathione by two orders of magnitude. In contrast, a replacement of C74 by Ser or Ala only marginally affected activity and specificity of DmGPx. Furthermore, LC-MS/MS analysis of oxidized DmGPx exposed to a reduced Trx C35S mutant yielded a dead-end intermediate containing a disulfide between Trx C32 and DmGPx C91. Thus, the catalytic mechanism of DmGPx, unlike that of selenocysteine (Sec)GPxs, involves formation of an internal disulfide that is pivotal to the interaction with Trx. Hereby C91, like the analogous second cysteine in 2-cysteine peroxiredoxins, adopts the role of a "resolving" cysteine (C(R)). Molecular modeling and homology considerations based on 450 GPxs suggest peculiar features to determine Trx specificity: (i) a non-aligned second Cys within the fourth helix that acts as C(R); (ii) deletions of the subunit interfaces typical of tetrameric GPxs leading to flexibility of the C(R)-containing loop. Based of these characteristics, most of the non-mammalian CysGPxs, in functional terms, are thioredoxin peroxidases.
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Affiliation(s)
- Matilde Maiorino
- Department of Biological Chemistry, University of Padova, I-35121 Padova, Italy.
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Maiorino M, Roveri A, Benazzi L, Bosello V, Mauri P, Toppo S, Tosatto SCE, Ursini F. Functional Interaction of Phospholipid Hydroperoxide Glutathione Peroxidase with Sperm Mitochondrion-associated Cysteine-rich Protein Discloses the Adjacent Cysteine Motif as a New Substrate of the Selenoperoxidase. J Biol Chem 2005; 280:38395-402. [PMID: 16159880 DOI: 10.1074/jbc.m505983200] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The mitochondrial capsule is a selenium- and disulfide-rich structure enchasing the outer mitochondrial membrane of mammalian spermatozoa. Among the proteins solubilized from the sperm mitochondrial capsule, we confirmed, by using a proteomic approach, the presence of phospholipid hydroperoxide glutathione peroxidase (PHGPx) as a major component, and we also identified the sperm mitochondrion-associated cysteine-rich protein (SMCP) and fragments/aggregates of specific keratins that previously escaped detection (Ursini, F., Heim, S., Kiess, M., Maiorino, M., Roveri, A., Wissing, J., and Flohé, L. (1999) Science 285, 1393-1396). The evidence for a functional association between PHGPx, SMCP, and keratins is further supported by the identification of a sequence motif of regularly spaced Cys-Cys doublets common to SMCP and high sulfur keratin-associated proteins, involved in bundling hair shaft keratin by disulfide cross-linking. Following the oxidative polymerization of mitochondrial capsule proteins, catalyzed by PHGPx, two-dimensional redox electrophoresis analysis showed homo- and heteropolymers of SMCP and PHGPx, together with other minor components. Adjacent cysteine residues in SMCP peptides are oxidized to cystine by PHGPx. This unusual disulfide is known to drive, by reshuffling oxidative protein folding. On this basis we propose that oxidative polymerization of the mitochondrial capsule is primed by the formation of cystine on SMCP, followed by reshuffling. Occurrence of reshuffling is further supported by the calculated thermodynamic gain of the process. This study suggests a new mechanism where selenium catalysis drives the cross-linking of structural elements of the cytoskeleton via the oxidation of a keratin-associated protein.
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Conrad M, Moreno SG, Sinowatz F, Ursini F, Kölle S, Roveri A, Brielmeier M, Wurst W, Maiorino M, Bornkamm GW. The nuclear form of phospholipid hydroperoxide glutathione peroxidase is a protein thiol peroxidase contributing to sperm chromatin stability. Mol Cell Biol 2005; 25:7637-44. [PMID: 16107710 PMCID: PMC1190272 DOI: 10.1128/mcb.25.17.7637-7644.2005] [Citation(s) in RCA: 180] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
The selenoenzyme phospholipid hydroperoxide glutathione peroxidase (PHGPx) is regarded as the major molecular target of selenodeficiency in rodents, accounting for most of the histopathological and structural abnormalities of testicular tissue and male germ cells. PHGPx exists as a cytosolic form, mitochondrial form, and nuclear form (nPHGPx) predominantly expressed in late spermatids and spermatozoa. Here, we demonstrate that mice with a targeted deletion of the nPHGPx gene were, unlike mice with the full knockout (KO) of PHGPx, not only viable but also, surprisingly, fully fertile. While both morphological analysis of testis and epididymis and sperm parameter measurements did not show any apparent abnormality, toluidine blue and acridine orange stainings of spermatozoa indicated defective chromatin condensation in the KO sperm isolated from the caput epididymis. Furthermore, upon drying and hydrating, KO sperm exhibited a significant proportion of morphologically abnormal heads. Monobromobimane labeling and protein-free thiol titration revealed significantly less extensive oxidation in the cauda epididymis when compared to that in the wild type. We conclude that nPHGPx, by acting as a protein thiol peroxidase in vivo, contributes to the structural stability of sperm chromatin.
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Affiliation(s)
- M Conrad
- Institute of Clinical Molecular Biology and Tumour Genetics, GSF Research Centre for Environment and Health, Munich, Germany.
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Maiorino M, Mauri P, Roveri A, Benazzi L, Toppo S, Bosello V, Ursini F. Primary structure of the nuclear forms of phospholipid hydroperoxide glutathione peroxidase (PHGPx) in rat spermatozoa. FEBS Lett 2005; 579:667-70. [PMID: 15670826 DOI: 10.1016/j.febslet.2004.12.041] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2004] [Revised: 12/10/2004] [Accepted: 12/13/2004] [Indexed: 11/17/2022]
Abstract
Phospholipid hydroperoxide glutathione peroxidase is a monomeric Se-peroxidase highly expressed in mammalian male germ cells. Its nuclear form, sperm nuclei glutathione peroxidase (snGPx), has been originally identified in maturating spermatozoa as a transcription product containing an alternative exon within the phospholipid hydroperoxide glutathione peroxidase gene. In this paper, we show that this form is inconstantly detectable in rat spermatozoa where a 20.0 and 25.9 kDa major forms are detected instead. These have been conclusively characterized. The N-terminus sequence of the 20.0 kDa form confirmed that the protein is identical to cytosolic form, suggesting diffusion into the nucleus. The 25.9 kDa protein represented a truncated form of the previously described nuclear snGPx, lacking the basic nuclear localization signal. This protein is present in two forms differing from each other by the presence of an N-terminal methionine. The presence of traces of the larger snGPx form suggests that exhaustive proteolytic processing of the precursor produces the 25.9 kDa enzyme, although the alternate use of a downstream ATG, at least in rodents, could not be unequivocally ruled out.
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Affiliation(s)
- Matilde Maiorino
- Department of Biological Chemistry, University of Padova, Viale G. Colombo 3, I-35121 Padova, Italy.
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Garolla A, Maiorino M, Roverato A, Roveri A, Ursini F, Foresta C. Oral carnitine supplementation increases sperm motility in asthenozoospermic men with normal sperm phospholipid hydroperoxide glutathione peroxidase levels. Fertil Steril 2005; 83:355-61. [PMID: 15705374 DOI: 10.1016/j.fertnstert.2004.10.010] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2002] [Revised: 02/21/2003] [Accepted: 02/21/2003] [Indexed: 11/17/2022]
Abstract
OBJECTIVE To clarify the role of carnitine supplementation in idiopathic asthenozoospermia and to look for a rationale for its use in asthenozoospermic patients. DESIGN Blind clinical study. SETTING Academic. PATIENT(S) Thirty asthenozoospermic patients divided in two groups according to phospholipid hydroperoxide glutathione peroxidase (PHGPx) levels. INTERVENTION(S) Placebo for 3 months, then oral L-carnitine (2 g/day) for 3 months; semen samples were collected at baseline, after placebo, after carnitine administration, and again after 3 months with no drugs. MAIN OUTCOME MEASURE(S) Evaluation of seminal parameters and determination of seminal PHGPx levels, measured as rescued activity. RESULT(S) When asthenozoospermic subjects were divided in two groups on the basis of PHGPx levels, we observed an improvement of mean sperm motility only in the group of patients with normal PHGPx levels. CONCLUSION(S) Phospholipid hydroperoxide glutathione peroxidase has an important role in male infertility, and carnitine treatment might improve sperm motility in the presence of normal mitochondrial function.
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Affiliation(s)
- Andrea Garolla
- Histology, Microbiology and Medical Biotechnologies, University of Padova, Padova, Italy
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Mauri P, Benazzi L, Flohé L, Maiorino M, Pietta PG, Pilawa S, Roveri A, Ursini F. Versatility of selenium catalysis in PHGPx unraveled by LC/ESI-MS/MS. Biol Chem 2003; 384:575-88. [PMID: 12751787 DOI: 10.1515/bc.2003.065] [Citation(s) in RCA: 78] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Phospholipid hydroperoxide glutathione peroxidase (PHGPx; EC 1.11.1.12), a broad-spectrum thiol-dependent peroxidase, deserves renewed interest as a regulatory factor in various signaling cascades and as a structural protein in sperm cells. We present a first attempt to identify catalytic intermediates and derivatives of the selenoprotein by liquid chromatography coupled to electrospray tandem mass spectrometry (LC/ESI-MS/MS) and to explain observed specificities by molecular modeling. The ground state enzyme E proved to correspond to position 3-170 of the deduced porcine sequence with selenium being present as selenocysteine at position 46. The selenenic acid form, which is considered to be the first catalytic intermediate F formed by reaction with hydroperoxide, could not be identified. The second catalytic intermediate G was detected as Se-glutathionylated enzyme. This intermediate is generated in the reverse reaction where the active site selenol interacts with glutathione disulfide (GSSG). According to molecular models, specific binding of reduced glutathione (GSH) and of GSSG is inter alia facilitated by electrostatic attraction of Lys-48 and Lys-125. Polymerization of PHGPx is obtained under oxidizing conditions in the absence of low molecular weight thiols. Analysis of MS spectra revealed that the process is due to a selective reaction of Sec-46 with Cys-148' resulting in linear polymers representing dead-end intermediates (G'). FT Docking of PHGPx molecules allowed reactions of Sec-46 with either Cys-66', Cys-107', Cys-168' or Cys-148', the latter option being most likely as judged by the number of proposed intermediates with reasonable hydrogen bonds, interaction energies and interface areas. We conclude that the same catalytic principles, depending on the conditions, can drive the diverse actions of PHGPx, i.e. hydroperoxide reduction, GSSG reduction, S-derivatization and self-incorporation into biological structures.
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Affiliation(s)
- Pierluigi Mauri
- Institute for Biomedical Technologies, National Research Council, Viale F.lli Cervi 93, 1-20090 Segrate (Milano), Italy
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Flohé L, Foresta C, Garolla A, Roveri A, Ursini F, Wissing J, Maiorino M. PHGPx is the mitochondrial capsule selenoprotein of mammalian sperm. Andrologia 2003. [DOI: 10.1046/j.1439-0272.2003.00531_8.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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39
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Affiliation(s)
- Leopold Flohé
- Department of Biochemistry, Technical University of Braunschweig D-38124 Braunschweig, Germany.
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Foresta C, Flohé L, Garolla A, Roveri A, Ursini F, Maiorino M. Male fertility is linked to the selenoprotein phospholipid hydroperoxide glutathione peroxidase. Biol Reprod 2002; 67:967-71. [PMID: 12193409 DOI: 10.1095/biolreprod.102.003822] [Citation(s) in RCA: 203] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
The selenoprotein phospholipid hydroperoxide glutathione peroxidase (PHGPx) accounts for almost the entire selenium content of mammalian testis. PHGPx is abundantly expressed in spermatids as active peroxidase but is transformed to an oxidatively inactivated protein in mature sperm, where it is a major constituent of the mitochondrial capsule in the midpiece. Male infertility in selenium-deficient animals, which is characterized by impaired sperm motility and morphological midpiece alterations, is considered to result from insufficient PHGPx content. We studied the relationship between sperm PHGPx, measured as rescued activity, and human fertility. Sperm specimens from 75 infertile men and 37 controls were analyzed for fertility-related parameters according to World Health Organization criteria. The PHGPx protein content was estimated after reductive solubilization of the spermatozoa by measuring the rescued PHGPx activity. Rescued PHGPx activity of infertile men ranged significantly below that of controls (93.2 +/- 60.1 units/mg sperm protein vs. 187.5 +/- 55.3 units/mg) and was particularly low in oligoasthenozoospermic specimens (61.93 +/- 45.42 units/mg; P < 0.001 compared with controls and asthenozoospermic samples). Rescued PHGPx activity was correlated positively with viability, morphological integrity, and most profoundly forward motility (r = 0.35, 0.44, and 0.45, respectively). In isolated motile samples, motility decreased faster with decreasing PHGPx content. In humans, PHGPx appears to be indispensable for structural integrity of spermatozoa and to codetermine sperm motility and viability. Because the content of PHGPx, irrespective of the cause of alteration, is correlated with fertility-related parameters, PHGPx can be considered a predictive measure for fertilization capacity.
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Affiliation(s)
- Carlo Foresta
- Department of Medical and Surgical Sciences, Clinica Medica 3, University of Padova, I-35128 Padova, Italy
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41
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Affiliation(s)
- Antonella Roveri
- Department of Biological Chemistry, University of Padova, I-35121 Padova, Italy
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Abstract
BACKGROUND While metabolically generated oxidants are produced locally in experimental glomerular diseases, little is still known of their significance and the respective scavenger systems in human glomerular diseases. METHODS Here we studied kidneys from patients with congenital nephrotic syndrome of the Finnish type (CNF), a human model disease of isolated proteinuria. Expression of specific mRNAs for a major antioxidant system against lipoperoxidation [phospholipid hydroperoxide glutathione peroxidase (PHGPx)] and for mitochondrial proteins were studied in Northern blotting together with analysis of PHGPx in semiquantitative reverse transcription-polymerase chain reaction (RT-PCR). The respective proteins and lipoperoxide (LPO) adducts malonyldialdehyde (MDA) and 4-hydroxynonenal (4-HNE) were analyzed in immunohistochemistry. RESULTS PHGPx and the mitochondrially encoded subunits of cytochrome-c-oxidase were distinctly down-regulated within the glomeruli of CNF kidneys. These changes were confirmed in semiquantitative RT-PCR. Increases of lipoperoxidation products MDA and 4-HNE were constantly found in the glomeruli of CNF. In agreement with findings in CNF, similar results were obtained in biopsies from other human glomerular diseases. CONCLUSIONS These findings suggest that local mitochondrial damage initiates LPO, which then causes deposition of the cytotoxic LPO products in glomeruli, as seen especially in CNF kidneys. Together with down-regulation of the local antioxidant protection, these may be important pathophysiologic mechanisms in human glomerular disease.
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Affiliation(s)
- M L Solin
- The Haartman Institute, Division of Bacteriology and Immunology, University of Helsinki, Helsinki, Finland
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Abstract
PHGPx of rat sperm mitochondrial capsule is cross-linked and inactive. The enzyme is in part released in an active form by mercaptoethanol. Treatment with H(2)O(2) of reduced and solubilised capsule proteins, in the absence of any added reductant, results in: i) H(2)O(2) consumption which depends on the presence of both, PHGPx activity and protein thiols; ii) protein thiol oxidation with a stoichiometry of 2 equivalents of thiol per mole of hydroperoxide and, iii) PHGPx inactivation and cross-linking. SDS-PAGE analysis of monobromobimane-labeled proteins, following incubation with H(2)O(2), shows that the oxidation takes place in specific bands in the area of 20~kDa. It is concluded that the protein thiol peroxidase activity of PHGPx is responsible for cross-linking proteins in the mammalian sperm capsule and accounts for the selenium dependency of spermatogenesis.
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Affiliation(s)
- A Roveri
- Department of Biological Chemistry, University of Padova, Viale G. Colombo 3, I-35121 Padova, Italy
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Abstract
The selenoprotein phospholipid hydroperoxide glutathione peroxidase (PHGPx) changes its physical characteristics and biological functions during sperm maturation. PHGPx exists as a soluble peroxidase in spermatids but persists in mature spermatozoa as an enzymatically inactive, oxidatively cross-linked, insoluble protein. In the midpiece of mature spermatozoa, PHGPx protein represents at least 50 percent of the capsule material that embeds the helix of mitochondria. The role of PHGPx as a structural protein may explain the mechanical instability of the mitochondrial midpiece that is observed in selenium deficiency.
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Affiliation(s)
- F Ursini
- Dipartmento di Chimica Biologica, Università di Padova, Viale G. Colombo 3, I-35121 Padova, Italy
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45
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Affiliation(s)
- M Maiorino
- Dipartimento di Chimica Biologica, Padova, Italy
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46
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Maiorino M, Wissing JB, Brigelius-Flohé R, Calabrese F, Roveri A, Steinert P, Ursini F, Flohé L. Testosterone mediates expression of the selenoprotein PHGPx by induction of spermatogenesis and not by direct transcriptional gene activation. FASEB J 1998; 12:1359-70. [PMID: 9761779 DOI: 10.1096/fasebj.12.13.1359] [Citation(s) in RCA: 118] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Selenium deficiency is known to be associated with male infertility, and the selenoprotein PHGPx has been shown to increase in rat testis after puberty and to depend on gonadotropin stimulation in hypophysectomized rats [Roveri et al. (1992) J. Biol. Chem. 267, 6142 6146]. Exposure of decapsulated whole testis, however, failed to reveal any transcriptional activation or inhibition of the PHGPx gene by testosterone, human chorionic gonadotropin, or forskolin. Nevertheless, it was verified that the specific activity of PHGPx in testis, but not of cGPx, correlated with sexual maturation. Leydig cell destruction in vivo by ethane dimethane sulfonate (EDS) resulted in a delayed decrease in PHGPx activity and mRNA that could be completely prevented by testosterone substitution. cGPx transiently increased upon EDS treatment, probably as a result of reactive macrophage augmentation. In situ mRNA hybridization studies demonstrated an uncharacteristic low level of cGPx transcription in testis, whereas PHGPx mRNA was abundantly and preferentially expressed in round spermatids. The data show that the age or gonadotropin-dependent expression of PHGPx in testis does not result from direct transcriptional gene activation by testosterone, but is due to differentiation stage-specific expression in late spermatids, which are under the control of Leydig cell-derived testosterone. The striking burst of PHGPx expression at the transition of round to elongated spermatids suggests an involvement of this selenoprotein in sperm maturation.
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Affiliation(s)
- M Maiorino
- Dipartimento di Chimica Biologica, I-35121 Padova, Italy.
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47
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Maiorino M, Aumann KD, Brigelius-Flohé R, Doria D, van den Heuvel J, McCarthy J, Roveri A, Ursini F, Flohé L. Probing the presumed catalytic triad of a selenium-containing peroxidase by mutational analysis. Z Ernahrungswiss 1998; 37 Suppl 1:118-21. [PMID: 9558742] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Glutathione peroxidases (GPx) are characterized by a catalytically active selenium which forms the center of a strictly conserved triad composed of selenocysteine, glutamine, and tryptophan. In order to check the functional relevance of this structural peculiarity, six molecular mutants of phospholipid hydroperoxide glutathione peroxidase (PHGPx) were designed, isolated, and investigated kinetically. Replacement of the selenocysteine in position 46 by cysteine decreased k + 1, i.e., the reaction rate of reduced enzyme with hydroperoxide, by three orders of magnitude. The rate of regeneration of the reduced enzyme by glutathione (k' + 2) was similarly affected. Additional substitution of Gln81 or Trp136 by acid residues resulted in a further decrease of k + 1 by three orders of magnitude, whereas histidine or neutral residues in these positions proved to be less deleterious. The data support the hypothesis that the typical triad of selenocysteine, glutamine, and tryptophan is indeed a novel catalytic center in which the reactivity of selenium is optimized by hydrogen bonding provided by the adjacent glutamine and tryptophan residues.
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Affiliation(s)
- M Maiorino
- Department of Biological Chemistry, University of Padova, Italy
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48
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Ursini F, Maiorino M, Roveri A. Phospholipid hydroperoxide glutathione peroxidase (PHGPx): more than an antioxidant enzyme? Biomed Environ Sci 1997; 10:327-332. [PMID: 9315326] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
The family of glutathione peroxidases encompasses, as far, three tetrameric glutathione peroxidases (GPx) and the monomeric PHGPx. Although the overall homology between tetrameric enzymes and PHGPx is less than 30%, a pronounced similarity has been detected on clusters involved in the active site and a common catalytic triad (selenocysteine glutamine and tryptophan) has been defined by structural and kinetic data. A major peculiar feature of the reaction catalyzed by PHGPx is the possibility to accommodate large lipophilic substrates. This accounts for the observed dramatic antiperoxidant effect and the synergism with vitamin E. Moreover, the reduction of lipid hydroperoxides accounts also for the observed modulation of cycloxygenase and inhibition of 15-lipoxygenase. On the other hand, structural and kinetic data indicate that also the specificity of PHGPx for the donor substrate is not restricted to GSH and the recent observation the PHGPx binds to specific mitochondrial proteins, from which it is released by ionic strength and thiols, suggests a possible fole of this selenoenzyme in catalyzing the specific oxidation of protein thiols, thus modulating the activity of cellular regulatory elements. On this light, the selenium mojety of PHGPx, reacting much faster that thiols with a peroxide, and then oxidizing specific protein thiols, would channel the oxidation toward protein targets, thus providing, by protein-protein interaction, the specificity of the redox transition.
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Affiliation(s)
- F Ursini
- Department of Biological Chemistry, University of Padova, Italy
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Godeas C, Tramer F, Micali F, Roveri A, Maiorino M, Nisii C, Sandri G, Panfili E. Phospholipid hydroperoxide glutathione peroxidase (PHGPx) in rat testis nuclei is bound to chromatin. Biochem Mol Med 1996; 59:118-24. [PMID: 8986633 DOI: 10.1006/bmme.1996.0076] [Citation(s) in RCA: 80] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
In rat testis nuclei the activity of the selenoenzyme phospholipid hydroperoxide glutathione peroxidase (PHGPx, EC 1.11.1.12) is much higher than in other tissues and subcellular compartments, with the sole exception of mitochondria. In nuclei, the bound enzyme is solubilized by DNase I treatment, thus suggesting a binding to chromatin. Treatment with ionic strength releases about 70% of bound PHGPx, suggesting that electrostatic bonds are involved. Immunogold electron microscopy indicates the association of PHGPx with chromatin structures in isolated nuclei. A possible interpretation of these data is a PHGPx protective role against DNA peroxidative damage. Furthermore, in agreement with kinetic and structural information, PHGPx-chromatin binding could suggest an hypothetical thiol oxidase activity toward specific thiol bearing proteins which could substitute for GSH as alternative donor substrates. Such activity could give to the enzyme a new important function which is not only protective but also has a specific regulatory function in chromatin condensation.
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Affiliation(s)
- C Godeas
- Department of Biochemistry, Biophysics and Macromolecular Chemistry, University of Trieste, Trieste, 1-34127, Italy.
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Zamburlini A, Maiorino M, Barbera P, Roveri A, Ursini F. Direct measurement by single photon counting of lipid hydroperoxides in human plasma and lipoproteins. Anal Biochem 1995; 232:107-13. [PMID: 8600817 DOI: 10.1006/abio.1995.9953] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
A single photon counting procedure for measuring lipid hydroperoxides in human plasma or LDL-VLDL, escaping from extraction and chromatography, is described. This appears to be a relevant procedure because the recovery of phospholipid hydroperoxides from plasma is a critical point which, in our hands, was limited and poorly reproducible. The sample is added to a reaction mixture containing luminol, hemin, and Triton X-100 in an alkaline buffer, the photon emission is recorded, and the data are processed using the monoexponential decay of the photon emission rate. The measurement is applied to (a) plasma passed through a "desalting" cartridge to eliminate the small water-soluble antioxidants which inhibit the chemiluminescent process or (b) apo-B-containing lipoproteins (LDL-VLDL) isolated by heparin-Sepharose affinity chromatography. The content of lipid hydroperoxides is calculated using an internal calibration with palmitoyllinoleoylphosphatidylcholine hydroperoxide. This procedure, based on a single photon counting technology, was adopted to produce reliable results using samples from which inhibitors of the photon emission process have not been completely eliminated. The specificity of the signal for lipid hydroperoxides was validated by its complete disappearance following incubation of the sample with glutathione and phospholipid-hydroperoxide glutathione peroxidase (EC 1.11.1.12), the sole enzyme specific for all classes of lipid hydroperoxides in lipoproteins. The interassay variability was < 10%. The results indicated that the concentration of lipid hydroperoxides in the plasma of 20 healthy subjects was 353 +/- 78 nM. In different subjects, LDL-VLDL accounted for 40-80% of the lipid hydroperoxides in plasma.
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Affiliation(s)
- A Zamburlini
- Department of Biological Chemistry, University of Padua, Italy
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