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Pradier A, Mamez AC, Stephan C, Giannotti F, Masouridi-Levrat S, Wang S, Morin S, Neofytos D, Vu DL, Melotti A, Arm I, Eberhardt CS, Tamburini J, Kaiser L, Chalandon Y, Simonetta F. T Cell Receptor Sequencing Reveals Reduced Clonal Breadth of T Cell Responses against SARS-CoV-2 after Natural Infection and Vaccination in Allogeneic Hematopoietic Stem Cell Transplant Recipients. Ann Oncol 2022; 33:1333-1335. [PMID: 36116692 PMCID: PMC9477612 DOI: 10.1016/j.annonc.2022.09.153] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2022] [Revised: 08/30/2022] [Accepted: 09/02/2022] [Indexed: 12/01/2022] Open
Affiliation(s)
- A Pradier
- Division of Hematology, Department of Oncology, Geneva University Hospitals, University of Geneva, Geneva, Switzerland; Translational Research Centre in Onco-Haematology, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - A C Mamez
- Division of Hematology, Department of Oncology, Geneva University Hospitals, University of Geneva, Geneva, Switzerland.
| | - C Stephan
- Division of Hematology, Department of Oncology, Geneva University Hospitals, University of Geneva, Geneva, Switzerland
| | - F Giannotti
- Division of Hematology, Department of Oncology, Geneva University Hospitals, University of Geneva, Geneva, Switzerland
| | - S Masouridi-Levrat
- Division of Hematology, Department of Oncology, Geneva University Hospitals, University of Geneva, Geneva, Switzerland
| | - S Wang
- Translational Research Centre in Onco-Haematology, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - S Morin
- Division of Hematology, Department of Oncology, Geneva University Hospitals, University of Geneva, Geneva, Switzerland
| | - D Neofytos
- Division of Infectious Diseases, Geneva University Hospitals, Geneva, Switzerland
| | - D L Vu
- Division of Infectious Diseases, Geneva University Hospitals, Geneva, Switzerland
| | - A Melotti
- Translational Research Centre in Onco-Haematology, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - I Arm
- Laboratory of Virology, Division of Infectious Diseases and Division of Laboratory Medicine, University Hospitals of Geneva & Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - C S Eberhardt
- Center for Vaccinology, University Hospitals of Geneva Division of General Pediatrics, Department of Woman, Child and Adolescent Medicine, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - J Tamburini
- Translational Research Centre in Onco-Haematology, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - L Kaiser
- Division of Infectious Diseases, Geneva University Hospitals, Geneva, Switzerland; Laboratory of Virology, Division of Infectious Diseases and Division of Laboratory Medicine, University Hospitals of Geneva & Faculty of Medicine, University of Geneva, Geneva, Switzerland; Geneva Centre for Emerging Viral Diseases, Geneva University Hospitals, Geneva, Switzerland
| | - Y Chalandon
- Division of Hematology, Department of Oncology, Geneva University Hospitals, University of Geneva, Geneva, Switzerland; Translational Research Centre in Onco-Haematology, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - F Simonetta
- Division of Hematology, Department of Oncology, Geneva University Hospitals, University of Geneva, Geneva, Switzerland; Translational Research Centre in Onco-Haematology, Faculty of Medicine, University of Geneva, Geneva, Switzerland.
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Pradier A, Cordey S, Zanella MC, Melotti A, Wang S, Mamez AC, Chalandon Y, Masouridi-Levrat S, Kaiser L, Simonetta F, Vu DL. Human pegivirus-1 replication influences NK cell reconstitution after allogeneic haematopoietic stem cell transplantation. Front Immunol 2022; 13:1060886. [PMID: 36713419 PMCID: PMC9876574 DOI: 10.3389/fimmu.2022.1060886] [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] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2022] [Accepted: 12/15/2022] [Indexed: 01/12/2023] Open
Abstract
Introduction Human pegivirus-1 (HPgV-1) is a so-called commensal virus for which no known associated organ disease has been found to date. Yet, it affects immune-reconstitution as previously studied in the HIV population, in whom active co-infection with HPgV-1 can modulate T and NK cell activation and differentiation leading to a protective effect against the evolution of the disease. Little is known on the effect of HPgV-1 on immune-reconstitution in allogeneic hematopoietic stem cell transplant (allo-HSCT) recipients, a patient population in which we and others have previously reported high prevalence of HPgV-1 replication. The aim of this study was to compare the immune reconstitution after allo-HSCT among HPgV-1-viremic and HPgV-1-non-viremic patients. Methods Within a cohort study of 40 allo-HSCT patients, 20 allo-HSCT recipients positive in plasma sample for HPgV-1 by rRT-PCR during the first year (1, 3, 6, 12 months) after transplantation were matched with 20 allo-HSCT recipients negative for HPgV-1. T and NK cell reconstitution was monitored by flow cytometry in peripheral blood samples from allo-HSCT recipients at the same time points. Results We observed no significant difference in the absolute number and subsets proportions of CD4 and CD8 T cells between patient groups at any analysed timepoint. We observed a significantly higher absolute number of NK cells at 3 months among HPgV-1-viremic patients. Immunophenotypic analysis showed a significantly higher proportion of CD56bright NK cells mirrored by a reduced percentage of CD56dim NK cells in HPgV-1-positive patients during the first 6 months after allo-HSCT. At 6 months post-allo-HSCT, NK cell phenotype significantly differed depending on HPgV-1, HPgV-1-viremic patients displaying NK cells with lower CD16 and CD57 expression compared with HPgV-1-negative patients. In accordance with their less differentiated phenotype, we detected a significantly reduced expression of granzyme B in NK cells in HPgV-1-viremic patients at 6 months. Discussion Our study shows that HPgV-1-viremic allo-HSCT recipients displayed an impaired NK cell, but not T cell, immune-reconstitution compared with HPgV-1-non-viremic patients, revealing for the first time a potential association between replication of the non-pathogenic HPgV-1 virus and immunomodulation after allo-HSCT.
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Affiliation(s)
- Amandine Pradier
- Faculty of Medicine, University of Geneva, Geneva, Switzerland
- Division of Haematology, Department of Oncology, Geneva University Hospitals, Geneva, Switzerland
- Translational Research Center for Oncohematology, Department of Medicine and Department of Pathology and Immunology, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Samuel Cordey
- Faculty of Medicine, University of Geneva, Geneva, Switzerland
- Laboratory of virology, Division of Laboratory Medicine, Geneva University Hospitals, Geneva, Switzerland
| | - Marie-Céline Zanella
- Laboratory of virology, Division of Laboratory Medicine, Geneva University Hospitals, Geneva, Switzerland
- Division of Infectious diseases, Geneva University Hospitals, Geneva, Switzerland
| | - Astrid Melotti
- Translational Research Center for Oncohematology, Department of Medicine and Department of Pathology and Immunology, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Sisi Wang
- Translational Research Center for Oncohematology, Department of Medicine and Department of Pathology and Immunology, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Anne-Claire Mamez
- Division of Haematology, Department of Oncology, Geneva University Hospitals, Geneva, Switzerland
| | - Yves Chalandon
- Faculty of Medicine, University of Geneva, Geneva, Switzerland
- Division of Haematology, Department of Oncology, Geneva University Hospitals, Geneva, Switzerland
- Translational Research Center for Oncohematology, Department of Medicine and Department of Pathology and Immunology, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | | | - Laurent Kaiser
- Faculty of Medicine, University of Geneva, Geneva, Switzerland
- Laboratory of virology, Division of Laboratory Medicine, Geneva University Hospitals, Geneva, Switzerland
- Division of Infectious diseases, Geneva University Hospitals, Geneva, Switzerland
- Center for emerging viruses, Geneva University Hospitals, Geneva, Switzerland
| | - Federico Simonetta
- Faculty of Medicine, University of Geneva, Geneva, Switzerland
- Division of Haematology, Department of Oncology, Geneva University Hospitals, Geneva, Switzerland
- Translational Research Center for Oncohematology, Department of Medicine and Department of Pathology and Immunology, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Diem-Lan Vu
- Faculty of Medicine, University of Geneva, Geneva, Switzerland
- Laboratory of virology, Division of Laboratory Medicine, Geneva University Hospitals, Geneva, Switzerland
- Division of Infectious diseases, Geneva University Hospitals, Geneva, Switzerland
- *Correspondence: Diem-Lan Vu, ;
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Lamrabet O, Melotti A, Burdet F, Hanna N, Perrin J, Nitschke J, Pagni M, Hilbi H, Soldati T, Cosson P. Transcriptional Responses of Dictyostelium discoideum Exposed to Different Classes of Bacteria. Front Microbiol 2020; 11:410. [PMID: 32210949 PMCID: PMC7078664 DOI: 10.3389/fmicb.2020.00410] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2019] [Accepted: 02/27/2020] [Indexed: 12/19/2022] Open
Abstract
Dictyostelium discoideum amoebae feed by ingesting bacteria, then killing them in phagosomes. Ingestion and killing of different bacteria have been shown to rely on largely different molecular mechanisms. One would thus expect that D. discoideum adapts its ingestion and killing machinery when encountering different bacteria. In this study, we investigated by RNA sequencing if and how D. discoideum amoebae respond to the presence of different bacteria by modifying their gene expression patterns. Each bacterial species analyzed induced a specific modification of the transcriptome. Bacteria such as Bacillus subtilis, Klebsiella pneumoniae, or Mycobacterium marinum induced a specific and different transcriptional response, while Micrococcus luteus did not trigger a significant gene regulation. Although folate has been proposed to be one of the key molecules secreted by bacteria and recognized by hunting amoebae, it elicited a very specific and restricted transcriptional signature, distinct from that triggered by any bacteria analyzed here. Our results indicate that D. discoideum amoebae respond in a highly specific, almost non-overlapping manner to different species of bacteria. We additionally identify specific sets of genes that can be used as reporters of the response of D. discoideum to different bacteria.
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Affiliation(s)
- Otmane Lamrabet
- Department of Cell Physiology and Metabolism, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Astrid Melotti
- Department of Cell Physiology and Metabolism, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Frédéric Burdet
- Vital-IT Group, SIB, Swiss Institute of Bioinformatics, Lausanne, Switzerland
| | - Nabil Hanna
- Department of Biochemistry, Faculty of Science, University of Geneva, Geneva, Switzerland
| | - Jackie Perrin
- Department of Cell Physiology and Metabolism, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Jahn Nitschke
- Department of Biochemistry, Faculty of Science, University of Geneva, Geneva, Switzerland
| | - Marco Pagni
- Vital-IT Group, SIB, Swiss Institute of Bioinformatics, Lausanne, Switzerland
| | - Hubert Hilbi
- Faculty of Medicine, Institute of Medical Microbiology, University of Zurich, Zurich, Switzerland
| | - Thierry Soldati
- Department of Biochemistry, Faculty of Science, University of Geneva, Geneva, Switzerland
| | - Pierre Cosson
- Department of Cell Physiology and Metabolism, Faculty of Medicine, University of Geneva, Geneva, Switzerland
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Leiba J, Sabra A, Bodinier R, Marchetti A, Lima WC, Melotti A, Perrin J, Burdet F, Pagni M, Soldati T, Lelong E, Cosson P. Vps13F links bacterial recognition and intracellular killing in Dictyostelium. Cell Microbiol 2017; 19. [PMID: 28076662 PMCID: PMC5484366 DOI: 10.1111/cmi.12722] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [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: 09/07/2016] [Revised: 01/06/2017] [Accepted: 01/06/2017] [Indexed: 12/22/2022]
Abstract
Bacterial sensing, ingestion, and killing by phagocytic cells are essential processes to protect the human body from infectious microorganisms. The cellular mechanisms involved in intracellular killing, their relative importance, and their specificity towards different bacteria are however poorly defined. In this study, we used Dictyostelium discoideum, a phagocytic cell model amenable to genetic analysis, to identify new gene products involved in intracellular killing. A random genetic screen led us to identify the role of Vps13F in intracellular killing of Klebsiella pneumoniae. Vps13F knock‐out (KO) cells exhibited a delayed intracellular killing of K. pneumoniae, although the general organization of the phagocytic and endocytic pathway appeared largely unaffected. Transcriptomic analysis revealed that vps13F KO cells may be functionally similar to previously characterized fspA KO cells, shown to be defective in folate sensing. Indeed, vps13F KO cells showed a decreased chemokinetic response to various stimulants, suggesting a direct or indirect role of Vps13F in intracellular signaling. Overstimulation with excess folate restored efficient killing in vps13F KO cells. Finally, genetic inactivation of Far1, the folate receptor, resulted in inefficient intracellular killing of K. pneumoniae. Together, these observations show that stimulation of Dictyostelium by bacterial folate is necessary for rapid intracellular killing of K. pneumoniae.
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Affiliation(s)
- Jade Leiba
- Department of Cell Physiology and Metabolism, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Ayman Sabra
- Department of Cell Physiology and Metabolism, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Romain Bodinier
- Department of Cell Physiology and Metabolism, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Anna Marchetti
- Department of Cell Physiology and Metabolism, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Wanessa C Lima
- Department of Cell Physiology and Metabolism, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Astrid Melotti
- Department of Cell Physiology and Metabolism, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Jackie Perrin
- Department of Cell Physiology and Metabolism, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Frederic Burdet
- Vital-IT, Swiss Institute of Bioinformatics, University of Lausanne, Lausanne, Switzerland
| | - Marco Pagni
- Vital-IT, Swiss Institute of Bioinformatics, University of Lausanne, Lausanne, Switzerland
| | - Thierry Soldati
- Department of Biochemistry, University of Geneva, Geneva, Switzerland
| | - Emmanuelle Lelong
- Genomic Research Laboratory, Division of Infectious Diseases, Geneva University Hospitals, Geneva, Switzerland
| | - Pierre Cosson
- Department of Cell Physiology and Metabolism, Faculty of Medicine, University of Geneva, Geneva, Switzerland
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Dorgham K, Cerini F, Gaertner H, Melotti A, Rossitto-Borlat I, Gorochov G, Hartley O. Generating Chemokine Analogs with Enhanced Pharmacological Properties Using Phage Display. Methods Enzymol 2016; 570:47-72. [DOI: 10.1016/bs.mie.2015.09.014] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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Lorente-Trigos A, Varnat F, Melotti A, Ruiz i Altaba A. BMP Signaling Promotes the Growth of Primary Human Colon Carcinomas in vivo. J Mol Cell Biol 2010; 2:318-32. [DOI: 10.1093/jmcb/mjq035] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
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Gaertner H, Lebeau O, Borlat I, Cerini F, Dufour B, Kuenzi G, Melotti A, Fish RJ, Offord R, Springael JY, Parmentier M, Hartley O. Highly potent HIV inhibition: engineering a key anti-HIV structure from PSC-RANTES into MIP-1 /CCL4. Protein Eng Des Sel 2008; 21:65-72. [DOI: 10.1093/protein/gzm079] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Hartley O, Gaertner H, Wilken J, Thompson D, Fish R, Ramos A, Pastore C, Dufour B, Cerini F, Melotti A, Heveker N, Picard L, Alizon M, Mosier D, Kent S, Offord R. Medicinal chemistry applied to a synthetic protein: development of highly potent HIV entry inhibitors. Proc Natl Acad Sci U S A 2004; 101:16460-5. [PMID: 15545608 PMCID: PMC534511 DOI: 10.1073/pnas.0404802101] [Citation(s) in RCA: 120] [Impact Index Per Article: 6.0] [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] [Indexed: 12/28/2022] Open
Abstract
We have used total chemical synthesis to perform high-resolution dissection of the pharmacophore of a potent anti-HIV protein, the aminooxypentane oxime of [glyoxylyl1]RANTES(2-68), known as AOP-RANTES, of which we designed and made 37 analogs. All involved incorporation of one or more rationally chosen nonnatural noncoded structures, for which we found a clear comparative advantage over coded ones. We investigated structure-activity relationships in the pharmacophore by screening the analogs for their ability to block the HIV entry process and produced a derivative, PSC-RANTES [N-nonanoyl, des-Ser1[L-thioproline2, L-cyclohexylglycine3]-RANTES(2-68)], which is 50 times more potent than AOP-RANTES. This promising group of compounds might be optimized yet further as potential prophylactic and therapeutic anti-HIV agents. The remarkable potency of our RANTES analogs probably involves the unusual mechanism of intracellular sequestration of CC-chemokine receptor 5 (CCR5), and it has been suggested that this arises from enhanced affinity for the receptor. We found that inhibitory potency and capacity to induce CCR5 down-modulation do appear to be correlated, but that unexpectedly, inhibitory potency and affinity for CCR5 do not. We believe this study represents the proof of principle for the use of a medicinal chemistry approach, above all one showing the advantage of noncoded structures, to the optimization of the pharmacological properties of a protein. Medicinal chemistry of small molecules is the foundation of modern pharmaceutical practice, and we believe we have shown that techniques have now reached the point at which the approach could also be applied to the many macromolecular drugs now in common use.
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Affiliation(s)
- Oliver Hartley
- Department of Structural Biology and Bioinformatics, Centre Médical Universitaire, 1211 Geneva 4, Switzerland
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Russell AP, Somm E, Debigaré R, Hartley O, Richard D, Gastaldi G, Melotti A, Michaud A, Giacobino JP, Muzzin P, LeBlanc P, Maltais F. COPD Results in a Reduction in UCP3 Long mRNA and UCP3 Protein Content in Types I and IIa Skeletal Muscle Fibers. ACTA ACUST UNITED AC 2004; 24:332-9. [PMID: 15602154 DOI: 10.1097/00008483-200409000-00009] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [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: 11/25/2022]
Abstract
PURPOSE Findings recently have shown coupling protein-3 (UCP3) content to be decreased in the skeletal muscle of patients with chronic obstructive pulmonary disease (COPD). Uncoupling protein-3 mRNA exists as two isoforms: long (UCP3L) and short (UCP3S). The UCP3 protein is expressed the least in oxidative and the most in glycolytic muscle fibers. Levels of UCP3 have been associated positively with intramyocellular triglyceride (IMTG) contents in conditions of altered fatty acid metabolism. As a source for muscle free fatty acid metabolism, IMTG is decreased in COPD. The current study completely characterized all the parameters of UCP3 expression (ie, UCP3L and UCP3S mRNA expression in whole muscle samples) and UCP3 protein content as well as IMTG content in the different fiber types in patients with COPD and healthy control subjects. METHODS Using real-time polymerase chain reaction, UCP3 gene expression was quantified. Skeletal muscle fiber type and UCP3 protein and IMTG content were measured using immunofluorescence and Oil red oil staining, respectively. RESULTS The findings showed that UCP3L mRNA expression was 44% lower (P < .005) in the patients with COPD than in the control subjects, whereas the UCP3S mRNA content was similar in the two groups. As compared with control subjects, UCP3 protein content was decreased by 89% and 83% and the IMTG content by 64% and 54%, respectively, in types I and IIa fibers (P < .0167) of patients with COPD, whereas they were unchanged in IIx fibers. CONCLUSIONS The reduced UCP3 and IMTG content in the more oxidative fibers may be linked to the altered muscle fatty acid metabolism associated with COPD. Further studies are required to determine the exact role and clinical relevance of the reduced UCP3 content in patients with COPD.
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Affiliation(s)
- Aaron P Russell
- Clinique Romande de Réadaptation SUVA Care, Sion, Switzerland.
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Russell AP, Somm E, Praz M, Crettenand A, Hartley O, Melotti A, Giacobino JP, Muzzin P, Gobelet C, Dériaz O. UCP3 protein regulation in human skeletal muscle fibre types I, IIa and IIx is dependent on exercise intensity. J Physiol 2003; 550:855-61. [PMID: 12794174 PMCID: PMC2343085 DOI: 10.1113/jphysiol.2003.040162] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.0] [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: 02/01/2023] Open
Abstract
It has been proposed that mitochondrial uncoupling protein 3 (UCP3) behaves as an uncoupler of oxidative phosphorylation. In a cross-sectional study, UCP3 protein levels were found to be lower in all fibre types of endurance-trained cyclists as compared to healthy controls. This decrease was greatest in the type I oxidative fibres, and it was hypothesised that this may be due to the preferential recruitment of these fibres during endurance training. To test this hypothesis, we compared the effects of 6 weeks of endurance (ETr) and sprint (STr) running training on UCP3 mRNA expression and fibre-type protein content using real-time PCR and immunofluorescence techniques, respectively. UCP3 mRNA and protein levels were downregulated similarly in ETr and STr (UCP3 mRNA: by 65 and 50%, respectively; protein: by 30 and 27%, respectively). ETr significantly reduced UCP3 protein content in type I, IIa and IIx muscle fibres by 54, 29 and 16%, respectively. STr significantly reduced UCP3 protein content in type I, IIa and IIx muscle fibres by 24, 31 and 26%, respectively. The fibre-type reductions in UCP3 due to ETr, but not STr, were significantly different from each other, with the effect being greater in type I than in type IIa, and in type IIa than in type IIx fibres. As a result, compared to STr, ETr reduced UCP3 expression significantly more in fibre type I and significantly less in fibre types IIx. This suggests that the more a fibre is recruited, the more it adapts to training by a decrease in its UCP3 expression. In addition, the more a fibre type depends on fatty acid beta oxidation and oxidative phosphorylation, the more it responds to ETr by a decrease in its UCP3 content.
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Affiliation(s)
- Aaron P Russell
- Clinique Romande de Réadaptation SUVA Care, Sion, Switzerland.
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