1
|
Pérez-Rodríguez M, Huertas JR, Villalba JM, Casuso RA. Mitochondrial adaptations to calorie restriction and bariatric surgery in human skeletal muscle: a systematic review with meta-analysis. Metabolism 2023; 138:155336. [PMID: 36302454 DOI: 10.1016/j.metabol.2022.155336] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/28/2022] [Revised: 10/11/2022] [Accepted: 10/17/2022] [Indexed: 11/18/2022]
Abstract
OBJECTIVE We performed a meta-analysis to determine the changes induced by calorie restriction (CR) and bariatric surgery on human skeletal muscle mitochondria. METHODS A systematic search of Medline and Web of Science was conducted. Controlled trials exploring CR (≥14 days) and mitochondrial function and/or content assessment were included. Moreover, studies analyzing weight loss following gastric surgery were included for comparison purposes. Human muscle data from 28 studies assessing CR (520 muscle samples) and from 10 studies assessing bariatric surgery (155 muscle samples) were analyzed in a random effect meta-analysis with three a priori chosen covariates. MAIN RESULTS We report a decrease (p < 0.05) (mean (95 % CI)) in maximal mitochondrial state 3 respiration in response to CR (-0.44 (-0.85, -0.03)) but not in response to surgery (-0.33 (-1.18, 0.52)). No changes in mitochondrial content were reported after CR (-0.05 (-0.12, 0.13)) or in response to surgery (0.23 (-0.05, 0.52)). Moreover, data from CR subjects showed a reduction in complex IV (CIV) activity (-0.29 (-0.56, -0.03)) but not in CIV content (-0.21 (-0.63, 0.22)). Similar results were obtained when the length of the protocol, the initial body mass index, and the estimated energy deficit were included in the model as covariates. CONCLUSION The observation of reduced maximal mitochondrial state 3, uncoupled respiration, and CIV activity without altering mitochondrial content suggests that, in human skeletal muscle, CR mainly modulates intrinsic mitochondrial function.
Collapse
Affiliation(s)
- Miguel Pérez-Rodríguez
- Department of Cell Biology, Physiology and Immunology, University of Córdoba, and ceiA3Campus of International Excellence in Agrifood, Spain
| | | | - José M Villalba
- Department of Cell Biology, Physiology and Immunology, University of Córdoba, and ceiA3Campus of International Excellence in Agrifood, Spain
| | - Rafael A Casuso
- Department of Physiology, University of Granada, Spain; Department of Health Sciences, Universidad Loyola Andalucía, Spain.
| |
Collapse
|
2
|
Gordaliza‐Alaguero I, Cantó C, Zorzano A. Metabolic implications of organelle-mitochondria communication. EMBO Rep 2019; 20:e47928. [PMID: 31418169 PMCID: PMC6726909 DOI: 10.15252/embr.201947928] [Citation(s) in RCA: 89] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2019] [Revised: 05/10/2019] [Accepted: 05/28/2019] [Indexed: 12/31/2022] Open
Abstract
Cellular organelles are not static but show dynamism-a property that is likely relevant for their function. In addition, they interact with other organelles in a highly dynamic manner. In this review, we analyze the proteins involved in the interaction between mitochondria and other cellular organelles, especially the endoplasmic reticulum, lipid droplets, and lysosomes. Recent results indicate that, on one hand, metabolic alterations perturb the interaction between mitochondria and other organelles, and, on the other hand, that deficiency in proteins involved in the tethering between mitochondria and the ER or in specific functions of the interaction leads to metabolic alterations in a variety of tissues. The interaction between organelles is an emerging field that will permit to identify key proteins, to delineate novel modulation pathways, and to elucidate their implications in human disease.
Collapse
Affiliation(s)
- Isabel Gordaliza‐Alaguero
- Institute for Research in Biomedicine (IRB Barcelona)Barcelona Institute of Science and Technology (BIST)BarcelonaSpain
- CIBER de Diabetes y Enfermedades Metabolicas AsociadasBarcelonaSpain
- Departamento de Bioquimica i Biomedicina MolecularFacultat de BiologiaUniversitat de BarcelonaBarcelonaSpain
| | - Carlos Cantó
- Nestle Institute of Health Sciences (NIHS)LausanneSwitzerland
- School of Life SciencesEcole Polytechnique Fédérale de Lausanne (EPFL)LausanneSwitzerland
| | - Antonio Zorzano
- Institute for Research in Biomedicine (IRB Barcelona)Barcelona Institute of Science and Technology (BIST)BarcelonaSpain
- CIBER de Diabetes y Enfermedades Metabolicas AsociadasBarcelonaSpain
- Departamento de Bioquimica i Biomedicina MolecularFacultat de BiologiaUniversitat de BarcelonaBarcelonaSpain
| |
Collapse
|
3
|
Hernández-Alvarez MI, Zorzano A. The Muscle Race After Bariatric Surgery: Ribosomal Proteins Come First. Diabetes 2016; 65:2476-8. [PMID: 27555574 DOI: 10.2337/dbi16-0035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Affiliation(s)
- María Isabel Hernández-Alvarez
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Barcelona, Spain; Departament de Bioquímica i Biomedicina Molecular, Facultat de Biologia, Universitat de Barcelona, Barcelona, Spain; and CIBER de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), Instituto de Salud Carlos III, Madrid, Spain
| | - Antonio Zorzano
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Barcelona, Spain; Departament de Bioquímica i Biomedicina Molecular, Facultat de Biologia, Universitat de Barcelona, Barcelona, Spain; and CIBER de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), Instituto de Salud Carlos III, Madrid, Spain
| |
Collapse
|
4
|
Jahansouz C, Serrot FJ, Frohnert BI, Foncea RE, Dorman RB, Slusarek B, Leslie DB, Bernlohr DA, Ikramuddin S. Roux-en-Y Gastric Bypass Acutely Decreases Protein Carbonylation and Increases Expression of Mitochondrial Biogenesis Genes in Subcutaneous Adipose Tissue. Obes Surg 2016; 25:2376-85. [PMID: 25975200 DOI: 10.1007/s11695-015-1708-5] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
BACKGROUND Mitochondrial dysfunction in adipose tissue has been implicated as a pathogenic step in the development of type 2 diabetes mellitus (T2DM). In adipose tissue, chronic nutrient overload results in mitochondria driven increased reactive oxygen species (ROS) leading to carbonylation of proteins that impair mitochondrial function and downregulation of key genes linked to mitochondrial biogenesis. In patients with T2DM, Roux-en-Y gastric bypass (RYGB) surgery leads to improvements in glycemic profile prior to significant weight loss. Consequently, we hypothesized that improved glycemia early after RYGB would be paralleled by decreased protein carbonylation and increased expression of genes related to mitochondrial biogenesis in adipose tissue. METHODS To evaluate this hypothesis, 16 obese individuals were studied before and 7-8 days following RYGB and adjustable gastric banding (AGB). Subcutaneous adipose tissue was obtained pre- and post-bariatric surgery as well as from eight healthy, non-obese individual controls. RESULTS Prior to surgery, adipose tissue expression of PGC1α, NRF1, Cyt C, and eNOS (but not Tfam) showed significantly lower expression in the obese bariatric surgery group when compared to lean controls (p < 0.05). Following RYGB, but not after AGB, patients showed significant decrease in HOMA-IR, reduction in adipose protein carbonylation, and increased expression of genes linked to mitochondrial biogenesis. CONCLUSIONS These results suggest that rapid reduction in protein carbonylation and increased mitochondrial biogenesis may explain postoperative metabolic improvements following RYGB.
Collapse
Affiliation(s)
- Cyrus Jahansouz
- Department of Surgery, University of Minnesota, 420 Delaware St. SE, MMC 195, Minneapolis, MN, 55455, USA
| | - Federico J Serrot
- Department of Surgery, University of Minnesota, 420 Delaware St. SE, MMC 195, Minneapolis, MN, 55455, USA
| | - Brigitte I Frohnert
- Division of Pediatric Endocrinology, Department of Pediatrics, University of Minnesota, 420 Delaware St. SE, MMC 195, Minneapolis, MN, 55455, USA
| | - Rocio E Foncea
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, 420 Delaware St. SE, MMC 195, Minneapolis, MN, 55455, USA
| | - Robert B Dorman
- Department of Surgery, University of Minnesota, 420 Delaware St. SE, MMC 195, Minneapolis, MN, 55455, USA
| | - Bridget Slusarek
- Department of Surgery, University of Minnesota, 420 Delaware St. SE, MMC 195, Minneapolis, MN, 55455, USA
| | - Daniel B Leslie
- Department of Surgery, University of Minnesota, 420 Delaware St. SE, MMC 195, Minneapolis, MN, 55455, USA
| | - David A Bernlohr
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, 420 Delaware St. SE, MMC 195, Minneapolis, MN, 55455, USA
| | - Sayeed Ikramuddin
- Department of Surgery, University of Minnesota, 420 Delaware St. SE, MMC 195, Minneapolis, MN, 55455, USA.
| |
Collapse
|
5
|
Zorzano A, Hernández-Alvarez MI, Sebastián D, Muñoz JP. Mitofusin 2 as a driver that controls energy metabolism and insulin signaling. Antioxid Redox Signal 2015; 22:1020-31. [PMID: 25567790 DOI: 10.1089/ars.2014.6208] [Citation(s) in RCA: 64] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
SIGNIFICANCE Mitochondrial dynamics is a complex process that impacts on mitochondrial biology. RECENT ADVANCES Recent evidence indicates that proteins participating in mitochondrial dynamics have additional cellular roles. Mitofusin 2 (Mfn2) is a potent modulator of mitochondrial metabolism with an impact on energy metabolism in muscle, liver, and hypothalamic neurons. In addition, Mfn2 is subjected to tight regulation. Hence, factors such as proinflammatory cytokines, lipid availability, or glucocorticoids block its expression, whereas exercise and increased energy expenditure promote its upregulation. CRITICAL ISSUES Importantly, Mfn2 controls cell metabolism and insulin signaling by limiting reactive oxygen species production and by modulation of endoplasmic reticulum stress. In this connection, it is critical to understand precisely the molecular mechanisms involved in the global actions of Mfn2. FUTURE DIRECTIONS Future directions should concentrate into the analysis of those mechanisms, and to fully demonstrate that Mfn2 represents a cellular hub that senses the metabolic and hormonal milieu and drives the control of metabolic homeostasis.
Collapse
Affiliation(s)
- Antonio Zorzano
- 1 Institute for Research in Biomedicine (IRB Barcelona) , Barcelona, Spain
| | | | | | | |
Collapse
|
6
|
Muñoz JP, Zorzano A. Analysis of mitochondrial morphology and function under conditions of mitofusin 2 deficiency. Methods Mol Biol 2015; 1265:307-320. [PMID: 25634283 DOI: 10.1007/978-1-4939-2288-8_21] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Recent discoveries linking mitochondrial dynamics to various pathologies have generated interest in the design of robust methods to screen proteins involved in mitochondrial dynamics and small molecules that modulate mitochondrial dynamics. Here, we describe functional screening protocols to analyze mitochondrial parameters such as mitochondrial morphology, reactive oxygen species (ROS) levels, mitochondrial calcium, and oxygen consumption rate in cultured cells. Novel proteins that participate in the regulation of mitochondrial dynamics and function can be identified using such an approach.
Collapse
Affiliation(s)
- Juan Pablo Muñoz
- Institute for Research in Biomedicine (IRB Barcelona), C/Baldiri Reixac 10, 08028, Barcelona, Spain
| | | |
Collapse
|
7
|
Schneeberger M, Dietrich MO, Sebastián D, Imbernón M, Castaño C, Garcia A, Esteban Y, Gonzalez-Franquesa A, Rodríguez IC, Bortolozzi A, Garcia-Roves PM, Gomis R, Nogueiras R, Horvath TL, Zorzano A, Claret M. Mitofusin 2 in POMC neurons connects ER stress with leptin resistance and energy imbalance. Cell 2013; 155:172-87. [PMID: 24074867 DOI: 10.1016/j.cell.2013.09.003] [Citation(s) in RCA: 398] [Impact Index Per Article: 36.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2013] [Revised: 07/09/2013] [Accepted: 08/22/2013] [Indexed: 11/26/2022]
Abstract
Mitofusin 2 (MFN2) plays critical roles in both mitochondrial fusion and the establishment of mitochondria-endoplasmic reticulum (ER) interactions. Hypothalamic ER stress has emerged as a causative factor for the development of leptin resistance, but the underlying mechanisms are largely unknown. Here, we show that mitochondria-ER contacts in anorexigenic pro-opiomelanocortin (POMC) neurons in the hypothalamus are decreased in diet-induced obesity. POMC-specific ablation of Mfn2 resulted in loss of mitochondria-ER contacts, defective POMC processing, ER stress-induced leptin resistance, hyperphagia, reduced energy expenditure, and obesity. Pharmacological relieve of hypothalamic ER stress reversed these metabolic alterations. Our data establish MFN2 in POMC neurons as an essential regulator of systemic energy balance by fine-tuning the mitochondrial-ER axis homeostasis and function. This previously unrecognized role for MFN2 argues for a crucial involvement in mediating ER stress-induced leptin resistance.
Collapse
Affiliation(s)
- Marc Schneeberger
- Diabetes and Obesity Research Laboratory, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), 08036 Barcelona, Spain; Department of Endocrinology and Nutrition, Hospital Clínic. School of Medicine, University of Barcelona, 08036 Barcelona, Spain; Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), 08036 Barcelona, Spain
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
8
|
Segalés J, Paz JC, Hernández-Alvarez MI, Sala D, Muñoz JP, Noguera E, Pich S, Palacín M, Enríquez JA, Zorzano A. A form of mitofusin 2 (Mfn2) lacking the transmembrane domains and the COOH-terminal end stimulates metabolism in muscle and liver cells. Am J Physiol Endocrinol Metab 2013; 305:E1208-21. [PMID: 23941871 DOI: 10.1152/ajpendo.00546.2012] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Mitofusin 2 (Mfn2), a protein that participates in mitochondrial fusion, is required to maintain normal mitochondrial metabolism in skeletal muscle and liver. Given that muscle Mfn2 is repressed in obese or type 2 diabetic subjects, this protein may have a potential pathophysiological role in these conditions. To evaluate whether the metabolic effects of Mfn2 can be dissociated from its function in mitochondrial dynamics, we studied a form of human Mfn2, lacking the two transmembrane domains and the COOH-terminal coiled coil (ΔMfn2). This form localized in mitochondria but did not alter mitochondrial morphology in cells or in skeletal muscle fibers. The expression of ΔMfn2 in mouse skeletal muscle stimulated glucose oxidation and enhanced respiratory control ratio, which occurred in the absence of changes in mitochondrial mass. ΔMfn2 did not stimulate mitochondrial respiration in Mfn2-deficient muscle cells. The expression of ΔMfn2 in mouse liver or in hepatoma cells stimulated gluconeogenesis. In addition, ΔMfn2 activated basal and maximal respiration both in muscle and liver cells. In all, we show that a form of Mfn2 lacking mitochondrial fusion activity stimulates mitochondrial function and enhances glucose metabolism in muscle and liver tissues. This study suggests that Mfn2 regulates metabolism independently of changes in mitochondrial morphology.
Collapse
Affiliation(s)
- Jessica Segalés
- Institute for Research in Biomedicine (IRB Barcelona Barcelona, Spain
| | | | | | | | | | | | | | | | | | | |
Collapse
|
9
|
Vijgen GHEJ, Bouvy ND, Hoeks J, Wijers S, Schrauwen P, van Marken Lichtenbelt WD. Impaired skeletal muscle mitochondrial function in morbidly obese patients is normalized one year after bariatric surgery. Surg Obes Relat Dis 2013; 9:936-41. [PMID: 23791452 DOI: 10.1016/j.soard.2013.03.009] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2013] [Revised: 01/08/2013] [Accepted: 03/22/2013] [Indexed: 11/17/2022]
Abstract
BACKGROUND Obesity and type 2 diabetes are associated with impaired skeletal muscle mitochondrial metabolism. As an intrinsic characteristic of an individual, skeletal muscle mitochondrial dysfunction could be a risk factor for weight gain and obesity-associated co-morbidities, such as type 2 diabetes. On the other hand, impaired skeletal muscle metabolism could be a consequence of obesity. We hypothesize that marked weight loss after bariatric surgery recovers skeletal muscle mitochondrial function. METHODS Skeletal muscle mitochondrial function as assessed by high-resolution respirometry was measured in 8 morbidly obese patients (body mass index [BMI], 41.3±4.7 kg/m(2); body fat, 48.3%±5.2%) before and 1 year after bariatric surgery (mean weight loss: 35.0±8.6 kg). The results were compared with a lean (BMI 22.8±1.1 kg/m(2); body fat, 15.6%±4.7%) and obese (BMI 33.5±4.2 kg/m(2); body fat, 34.1%±6.3%) control group. RESULTS Before surgery, adenosine diphosphate (ADP)-stimulated (state 3) respiration on glutamate/succinate was decreased compared with lean patients (9.5±2.4 versus 15.6±4.4 O2 flux/mtDNA; P<.05). One year after surgery, mitochondrial function was comparable to that of lean controls (after weight loss, 12.3±5.5; lean, 15.6±4.4 O2 flux/mtDNA). In addition, we observed an increased state 3 respiration on a lipid substrate after weight loss (10.0±3.2 versus 14.0±6.6 O2 flux/mtDNA; P< .05). CONCLUSION We conclude that impaired skeletal muscle mitochondrial function is a consequence of obesity that recovers after marked weight loss.
Collapse
Affiliation(s)
- Guy H E J Vijgen
- Department of Surgery, Maastricht University Medical Centre, Maastricht, the Netherlands; Department of Human Biology, School for Nutrition, Toxicology and Metabolism, NUTRIM, Maastricht, the Netherlands.
| | | | | | | | | | | |
Collapse
|
10
|
Mercader JM, Puiggros M, Segrè AV, Planet E, Sorianello E, Sebastian D, Rodriguez-Cuenca S, Ribas V, Bonàs-Guarch S, Draghici S, Yang C, Mora S, Vidal-Puig A, Dupuis J, Florez JC, Zorzano A, Torrents D. Identification of novel type 2 diabetes candidate genes involved in the crosstalk between the mitochondrial and the insulin signaling systems. PLoS Genet 2012; 8:e1003046. [PMID: 23236286 PMCID: PMC3516534 DOI: 10.1371/journal.pgen.1003046] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2012] [Accepted: 09/04/2012] [Indexed: 01/02/2023] Open
Abstract
Type 2 Diabetes (T2D) is a highly prevalent chronic metabolic disease with strong co-morbidity with obesity and cardiovascular diseases. There is growing evidence supporting the notion that a crosstalk between mitochondria and the insulin signaling cascade could be involved in the etiology of T2D and insulin resistance. In this study we investigated the molecular basis of this crosstalk by using systems biology approaches. We combined, filtered, and interrogated different types of functional interaction data, such as direct protein–protein interactions, co-expression analyses, and metabolic and signaling dependencies. As a result, we constructed the mitochondria-insulin (MITIN) network, which highlights 286 genes as candidate functional linkers between these two systems. The results of internal gene expression analysis of three independent experimental models of mitochondria and insulin signaling perturbations further support the connecting roles of these genes. In addition, we further assessed whether these genes are involved in the etiology of T2D using the genome-wide association study meta-analysis from the DIAGRAM consortium, involving 8,130 T2D cases and 38,987 controls. We found modest enrichment of genes associated with T2D amongst our linker genes (p = 0.0549), including three already validated T2D SNPs and 15 additional SNPs, which, when combined, were collectively associated to increased fasting glucose levels according to MAGIC genome wide meta-analysis (p = 8.12×10−5). This study highlights the potential of combining systems biology, experimental, and genome-wide association data mining for identifying novel genes and related variants that increase vulnerability to complex diseases. It has been shown that the crosstalk between insulin signaling and the mitochondria may be involved in the etiology of type 2 diabetes. In order to characterize the molecular basis of this crosstalk, we mined and filtered several interaction databases of different natures, including protein–protein interactions, gene co-expression, signaling, and metabolic pathway interactions, to identify reliable direct and indirect interactions between insulin signaling cascade and mitochondria genes. This allowed us to identify 286 genes that are associated simultaneously with insulin signaling and mitochondrial genes and therefore could act as a molecular bridge between both systems. We performed in vitro and in vivo experiments where the insulin signaling or the mitochondrial function were disrupted, and we found deregulation of these connecting genes. Finally, we found that common variants in genomic regions where these genes lie are enriched for genetic associations with type 2 diabetes and glycemic traits according to large genome-wide association meta-analyses. In summary, we reconstructed the network implicated in the crosstalk between the mitochondria and the insulin signaling and provide a list of genes connecting both systems. We also propose new potential type 2 diabetes candidate genes.
Collapse
Affiliation(s)
- Josep M. Mercader
- Joint IRB–BSC Program on Computational Biology, Barcelona Supercomputing Center, Barcelona, Catalonia, Spain
| | - Montserrat Puiggros
- Joint IRB–BSC Program on Computational Biology, Barcelona Supercomputing Center, Barcelona, Catalonia, Spain
- Computational Bioinformatics, National Institute of Bioinformatics, Madrid, Spain
| | - Ayellet V. Segrè
- Center for Human Genetic Research and Department of Molecular Biology, Massachusetts General Hospital, Boston, Massachusetts, United States of America
- Program in Medical and Population Genetics, Broad Institute, Cambridge, Massachusetts, United States of America
| | - Evarist Planet
- Biostatistics and Bioinformatics Unit, Institute for Research in Biomedicine, Barcelona, Spain
| | - Eleonora Sorianello
- Institute for Research in Biomedicine, Universitat de Barcelona, and CIBERDEM, Barcelona, Spain
| | - David Sebastian
- Institute for Research in Biomedicine, Universitat de Barcelona, and CIBERDEM, Barcelona, Spain
| | - Sergio Rodriguez-Cuenca
- University of Cambridge, Metabolic Research Laboratories Institute of Metabolic Sciences, Addenbrooke's Hospital, Cambridge, United Kingdom
| | - Vicent Ribas
- Institute for Research in Biomedicine, Universitat de Barcelona, and CIBERDEM, Barcelona, Spain
| | - Sílvia Bonàs-Guarch
- Joint IRB–BSC Program on Computational Biology, Barcelona Supercomputing Center, Barcelona, Catalonia, Spain
| | - Sorin Draghici
- Department of Computer Science, Department of Clinical and Translational Science, Department of Obstetrics and Gynecology, and Intelligent Systems and Bioinformatics Laboratory, Wayne State University, Detroit, Michigan, United States of America
| | - Chenjing Yang
- Institute of Translational Medicine, Cellular and Molecular Physiology, Liverpool, United Kingdom
| | - Sílvia Mora
- Institute of Translational Medicine, Cellular and Molecular Physiology, Liverpool, United Kingdom
| | - Antoni Vidal-Puig
- University of Cambridge, Metabolic Research Laboratories Institute of Metabolic Sciences, Addenbrooke's Hospital, Cambridge, United Kingdom
| | - Josée Dupuis
- Department of Biostatistics, Boston University School of Public Health, Boston, Massachusetts, United States of America
- National Heart, Lung, and Blood Institute's Framingham Heart Study, Framingham, Massachusetts, United States of America
| | | | - Jose C. Florez
- Program in Medical and Population Genetics, Broad Institute, Cambridge, Massachusetts, United States of America
- Diabetes Unit, Center for Human Genetic Research and Diabetes Research Center, Massachusetts General Hospital, Boston, Massachusetts, United States of America
- Department of Medicine, Harvard Medical School, Boston, Massachusetts, United States of America
| | | | - Antonio Zorzano
- Institute for Research in Biomedicine, Universitat de Barcelona, and CIBERDEM, Barcelona, Spain
| | - David Torrents
- Joint IRB–BSC Program on Computational Biology, Barcelona Supercomputing Center, Barcelona, Catalonia, Spain
- Institució Catalana de Recerca i Estudis Avançats (ICREA) Barcelona, Spain
- * E-mail:
| |
Collapse
|
11
|
Hunt SC, Hasstedt SJ, Xin Y, Dalley BK, Milash BA, Yakobson E, Gress RE, Davidson LE, Adams TD. Polymorphisms in the NPY2R gene show significant associations with BMI that are additive to FTO, MC4R, and NPFFR2 gene effects. Obesity (Silver Spring) 2011; 19:2241-7. [PMID: 21818152 PMCID: PMC3733173 DOI: 10.1038/oby.2011.239] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Neuropeptide Y (NPY) is an appetite hormone that acts centrally to control feeding behavior. The 5' and exon 2 regions of NPY2R, one of five NPY receptor genes, have been weakly and inconsistently implicated with obesity. With the ATG start site of the gene at the beginning of exon 2, single-nucleotide polymorphisms (SNPs) across intron 1 may show stronger associations with obesity than expected. Two 5' SNPs, three intron 1 SNPs, and one synonymous exon 2 SNP were genotyped on 2,985 white Utah subjects. Previously associated FTO, NPY, NPY1R, MC4R, PPARGC1A, OR7D4, and four NPFFR2 SNPs were also genotyped and related to BMI. One NPY2R 5' SNP (rs12649641, P = 0.008), an exon 2 SNP (rs2880415, P = 0.009), and an intron 1 SNP (rs17376826, P = 7 × 10(-6)) were each significantly associated with BMI. All three SNPs, plus FTO (rs9939609, P = 1.5 × 10(-6)) and two NPFFR2 SNPs (rs4129733, P = 3.7 × 10(-13) and rs11940196, 4.2 × 10(-10)) remained significant in a multiple regression additive model. Diplotypes using the estimated haplotypes of NPY2R, NPFFR2, and MC4R were significantly associated with BMI (P = 1.0 × 10(-10), 3.2 × 10(-8), and 1.1 × 10(-4), respectively). Haplotypes of NPY2R, NPFFR2, and MC4R, plus the FTO SNP, explained 9.6% of the BMI variance. SNP effect sizes per allele for the four genes ranged from 0.8 to 3.5 kg/m(2). We conclude that haplotypes containing the rs17376826 SNP in intron 1 of NPY2R have strong associations with BMI, some NPFFR2 haplotypes are strongly protective against or increase risk of obesity, and both NPY2R and NPFFR2 play important roles in obesity predisposition independent of FTO and MC4R.
Collapse
MESH Headings
- Adolescent
- Adult
- Aged
- Aged, 80 and over
- Alleles
- Alpha-Ketoglutarate-Dependent Dioxygenase FTO
- Body Mass Index
- Female
- Gene Frequency
- Genetic Loci
- Genetic Predisposition to Disease
- Genotype
- Haplotypes
- Humans
- Introns
- Linear Models
- Male
- Middle Aged
- Obesity/genetics
- Pedigree
- Polymorphism, Single Nucleotide
- Proteins/genetics
- Proteins/metabolism
- Receptor, Melanocortin, Type 4/genetics
- Receptor, Melanocortin, Type 4/metabolism
- Receptors, Neuropeptide/genetics
- Receptors, Neuropeptide/metabolism
- Receptors, Neuropeptide Y/genetics
- Receptors, Neuropeptide Y/metabolism
- Utah
- White People/genetics
- Young Adult
Collapse
Affiliation(s)
- Steven C Hunt
- Cardiovascular Genetics Division, Department of Internal Medicine, University of Utah School of Medicine, Salt Lake City, Utah, USA.
| | | | | | | | | | | | | | | | | |
Collapse
|
12
|
Wright LE, Brandon AE, Hoy AJ, Forsberg GB, Lelliott CJ, Reznick J, Löfgren L, Oscarsson J, Strömstedt M, Cooney GJ, Turner N. Amelioration of lipid-induced insulin resistance in rat skeletal muscle by overexpression of Pgc-1β involves reductions in long-chain acyl-CoA levels and oxidative stress. Diabetologia 2011; 54:1417-26. [PMID: 21331471 DOI: 10.1007/s00125-011-2068-x] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/02/2010] [Accepted: 01/06/2011] [Indexed: 02/08/2023]
Abstract
AIMS/HYPOTHESIS To determine if acute overexpression of peroxisome proliferator-activated receptor, gamma, coactivator 1 beta (Pgc-1β [also known as Ppargc1b]) in skeletal muscle improves insulin action in a rodent model of diet-induced insulin resistance. METHODS Rats were fed either a low-fat or high-fat diet (HFD) for 4 weeks. In vivo electroporation was used to overexpress Pgc-1β in the tibialis cranialis (TC) and extensor digitorum longus (EDL) muscles. Downstream effects of Pgc-1β on markers of mitochondrial oxidative capacity, oxidative stress and muscle lipid levels were characterised. Insulin action was examined ex vivo using intact muscle strips and in vivo via a hyperinsulinaemic-euglycaemic clamp. RESULTS Pgc-1β gene expression was increased >100% over basal levels. The levels of proteins involved in mitochondrial function, lipid metabolism and antioxidant defences, the activity of oxidative enzymes, and substrate oxidative capacity were all increased in muscles overexpressing Pgc-1β. In rats fed a HFD, increasing the levels of Pgc-1β partially ameliorated muscle insulin resistance, in association with decreased levels of long-chain acyl-CoAs (LCACoAs) and increased antioxidant defences. CONCLUSIONS Our data show that an increase in Pgc-1β expression in vivo activates a coordinated subset of genes that increase mitochondrial substrate oxidation, defend against oxidative stress and improve lipid-induced insulin resistance in skeletal muscle.
Collapse
Affiliation(s)
- L E Wright
- Diabetes & Obesity Research Program, Garvan Institute of Medical Research, 384 Victoria St, Darlinghurst, Sydney, NSW 2010, Australia
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
13
|
Deficiency of the mitochondrial electron transport chain in muscle does not cause insulin resistance. PLoS One 2011; 6:e19739. [PMID: 21589859 PMCID: PMC3093385 DOI: 10.1371/journal.pone.0019739] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2010] [Accepted: 04/14/2011] [Indexed: 01/28/2023] Open
Abstract
BACKGROUND It has been proposed that muscle insulin resistance in type 2 diabetes is due to a selective decrease in the components of the mitochondrial electron transport chain and results from accumulation of toxic products of incomplete fat oxidation. The purpose of the present study was to test this hypothesis. METHODOLOGY/PRINCIPAL FINDINGS Rats were made severely iron deficient, by means of an iron-deficient diet. Iron deficiency results in decreases of the iron containing mitochondrial respiratory chain proteins without affecting the enzymes of the fatty acid oxidation pathway. Insulin resistance was induced by feeding iron-deficient and control rats a high fat diet. Skeletal muscle insulin resistance was evaluated by measuring glucose transport activity in soleus muscle strips. Mitochondrial proteins were measured by Western blot. Iron deficiency resulted in a decrease in expression of iron containing proteins of the mitochondrial respiratory chain in muscle. Citrate synthase, a non-iron containing citrate cycle enzyme, and long chain acyl-CoA dehydrogenase (LCAD), used as a marker for the fatty acid oxidation pathway, were unaffected by the iron deficiency. Oleate oxidation by muscle homogenates was increased by high fat feeding and decreased by iron deficiency despite high fat feeding. The high fat diet caused severe insulin resistance of muscle glucose transport. Iron deficiency completely protected against the high fat diet-induced muscle insulin resistance. CONCLUSIONS/SIGNIFICANCE The results of the study argue against the hypothesis that a deficiency of the electron transport chain (ETC), and imbalance between the ETC and β-oxidation pathways, causes muscle insulin resistance.
Collapse
|
14
|
Dankel SN, Staalesen V, Bjørndal B, Berge RK, Mellgren G, Burri L. Tissue-specific effects of bariatric surgery including mitochondrial function. J Obes 2011; 2011:435245. [PMID: 21274278 PMCID: PMC3025372 DOI: 10.1155/2011/435245] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/02/2010] [Accepted: 12/14/2010] [Indexed: 12/25/2022] Open
Abstract
A better understanding of the molecular links between obesity and disease is potentially of great benefit for society. In this paper we discuss proposed mechanisms whereby bariatric surgery improves metabolic health, including acute effects on glucose metabolism and long-term effects on metabolic tissues (adipose tissue, skeletal muscle, and liver) and mitochondrial function. More short-term randomized controlled trials should be performed that include simultaneous measurement of metabolic parameters in different tissues, such as tissue gene expression, protein profile, and lipid content. By directly comparing different surgical procedures using a wider array of metabolic parameters, one may further unravel the mechanisms of aberrant metabolic regulation in obesity and related disorders.
Collapse
Affiliation(s)
- Simon N. Dankel
- Institute of Medicine, Haukeland University Hospital, University of Bergen, 5021 Bergen, Norway
- Hormone Laboratory, Haukeland University Hospital, 5021 Bergen, Norway
| | - Vidar Staalesen
- Institute of Medicine, Haukeland University Hospital, University of Bergen, 5021 Bergen, Norway
| | - Bodil Bjørndal
- Institute of Medicine, Haukeland University Hospital, University of Bergen, 5021 Bergen, Norway
| | - Rolf K. Berge
- Institute of Medicine, Haukeland University Hospital, University of Bergen, 5021 Bergen, Norway
| | - Gunnar Mellgren
- Institute of Medicine, Haukeland University Hospital, University of Bergen, 5021 Bergen, Norway
- Hormone Laboratory, Haukeland University Hospital, 5021 Bergen, Norway
- *Gunnar Mellgren:
| | - Lena Burri
- Institute of Medicine, Haukeland University Hospital, University of Bergen, 5021 Bergen, Norway
| |
Collapse
|
15
|
Ceretta LB, Réus GZ, Rezin GT, Scaini G, Streck EL, Quevedo J. Brain energy metabolism parameters in an animal model of diabetes. Metab Brain Dis 2010; 25:391-6. [PMID: 21088877 DOI: 10.1007/s11011-010-9220-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/06/2010] [Accepted: 10/27/2010] [Indexed: 12/30/2022]
Abstract
A growing body of evidence has indicated that altered mitochondrial function may be involved in mechanism for the development of diabetic complications. Thus, we investigated whether animal model of diabetes induced by alloxan alters energy metabolism parameters. Wistar rats received one single injection of alloxan (250 mg/kg) and after 15 days we evaluated mitochondrial respiratory chain complexes I, II, II-III and IV, creatine kinase and citrate synthase activities in prefrontal cortex, hippocampus and striatum. We observed that animal model of diabetes induced by alloxan increased complexes I and IV activities in hippocampus, complexes II and II-III activities in prefrontal cortex and striatum and complex IV in prefrontal cortex; however decreased complex IV activity in striatum. Moreover, diabetes rats decreased creatine kinase activity in striatum and increased citrate synthase activity in hippocampus. In conclusion, this study indicates that the alteration in mitochondrial function is probably involved in the pathophysiology of diabetes.
Collapse
Affiliation(s)
- Luciane B Ceretta
- Laboratório de Neurociências and Instituto Nacional de Ciência e Tecnologia Translacional em Medicina (INCT-TM), Programa de Pós-Graduação em Ciências da Saúde, Unidade Acadêmica de Ciências da Saúde, Universidade do Extremo Sul Catarinense, 88806-000, Criciúma, SC, Brazil
| | | | | | | | | | | |
Collapse
|
16
|
Hernández-Alvarez MI, Thabit H, Burns N, Shah S, Brema I, Hatunic M, Finucane F, Liesa M, Chiellini C, Naon D, Zorzano A, Nolan JJ. Subjects with early-onset type 2 diabetes show defective activation of the skeletal muscle PGC-1{alpha}/Mitofusin-2 regulatory pathway in response to physical activity. Diabetes Care 2010; 33:645-51. [PMID: 20032281 PMCID: PMC2827524 DOI: 10.2337/dc09-1305] [Citation(s) in RCA: 150] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
OBJECTIVE Type 2 diabetes is associated with insulin resistance and skeletal muscle mitochondrial dysfunction. We have found that subjects with early-onset type 2 diabetes show incapacity to increase Vo(2max) in response to chronic exercise. This suggests a defect in muscle mitochondrial response to exercise. Here, we have explored the nature of the mechanisms involved. RESEARCH DESIGN AND METHODS Muscle biopsies were collected from young type 2 diabetic subjects and obese control subjects before and after acute or chronic exercise protocols, and the expression of genes and/or proteins relevant to mitochondrial function was measured. In particular, the regulatory pathway peroxisome proliferator-activated receptor gamma coactivator (PGC)-1alpha/mitofusin-2 (Mfn2) was analyzed. RESULTS At baseline, subjects with diabetes showed reduced expression (by 26%) of the mitochondrial fusion protein Mfn2 and a 39% reduction of the alpha-subunit of ATP synthase. Porin expression was unchanged, consistent with normal mitochondrial mass. Chronic exercise led to a 2.8-fold increase in Mfn2, as well as increases in porin, and the alpha-subunit of ATP synthase in muscle from control subjects. However, Mfn2 was unchanged after chronic exercise in individuals with diabetes, whereas porin and alpha-subunit of ATP synthase were increased. Acute exercise caused a fourfold increase in PGC-1alpha expression in muscle from control subjects but not in subjects with diabetes. CONCLUSIONS Our results demonstrate alterations in the regulatory pathway that controls PGC-1alpha expression and induction of Mfn2 in muscle from patients with early-onset type 2 diabetes. Patients with early-onset type 2 diabetes display abnormalities in the exercise-dependent pathway that regulates the expression of PGC-1alpha and Mfn2.
Collapse
|
17
|
Zorzano A, Hernández-Alvarez MI, Palacín M, Mingrone G. Alterations in the mitochondrial regulatory pathways constituted by the nuclear co-factors PGC-1alpha or PGC-1beta and mitofusin 2 in skeletal muscle in type 2 diabetes. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2010; 1797:1028-33. [PMID: 20175989 DOI: 10.1016/j.bbabio.2010.02.017] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/17/2009] [Revised: 02/03/2010] [Accepted: 02/16/2010] [Indexed: 12/25/2022]
Abstract
Muscle mitochondrial metabolism is regulated by a number of factors, many of which are responsible for the transcription of nuclear genes encoding mitochondrial proteins such as PPARdelta, PGC-1alpha or PGC-1beta. Recent evidence indicates that proteins participating in mitochondrial dynamics also regulate mitochondrial metabolism. Thus, in cultured cells the mitochondrial fusion protein mitofusin 2 (Mfn2) stimulates respiration, substrate oxidation and the expression of subunits involved in respiratory complexes. Mitochondrial dysfunction has been reported in skeletal muscle of type 2 diabetic patients. Reduced mitochondrial mass and defective activity has been proposed to explain this dysfunction. Alterations in mitochondrial metabolism may be crucial to account for some of the pathophysiological traits that characterize type 2 diabetes. Skeletal muscle of type 2 diabetic patients shows reduced expression of PGC-1alpha, PGC-1beta, and Mfn2. In addition, a differential response to bilio-pancreatic diversion-induced weight loss in non-diabetic and type 2 diabetic patients has been reported. While non-diabetic morbidly obese subjects showed an increased expression of genes encoding Mfn2, PGC-1alpha, PGC-1beta, PPARdelta or SIRT1 in response to bariatric surgery-induced weight loss, no effect was detected in type 2 diabetic patients. These observations suggest the existence of a heritable component responsible for the abnormal control of the expression of genes encoding for modulators of mitochondrial biogenesis/metabolism, and which may participate in the development of the disease.
Collapse
Affiliation(s)
- Antonio Zorzano
- Institute for Research in Biomedicine (IRB Barcelona), C/Baldiri Reixac 10, 08028 Barcelona, Spain.
| | | | | | | |
Collapse
|
18
|
Ehrenborg E, Krook A. Regulation of skeletal muscle physiology and metabolism by peroxisome proliferator-activated receptor delta. Pharmacol Rev 2010; 61:373-93. [PMID: 19805479 DOI: 10.1124/pr.109.001560] [Citation(s) in RCA: 150] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Agonists directed against the alpha and gamma isoforms of the peroxisome proliferator-activated receptors (PPARs) have become important for the respective treatment of hypertriglyceridemia and insulin resistance associated with metabolic disease. PPARdelta is the least well characterized of the three PPAR isoforms. Skeletal muscle insulin resistance is a primary risk factor for the development of type 2 diabetes. There is increasing evidence that PPARdelta is an important regulator of skeletal muscle metabolism, in particular, muscle lipid oxidation, highlighting the potential utility of this isoform as a drug target. In addition, PPARdelta seems to be a key regulator of skeletal muscle fiber type and a possible mediator of the adaptations noted in skeletal muscle in response to exercise. In this review we summarize the current status regarding the regulation, and the metabolic effects, of PPARdelta in skeletal muscle.
Collapse
Affiliation(s)
- Ewa Ehrenborg
- Atherosclerosis Research Unit, Department of Medicine, Center for Molecular Medicine, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden
| | | |
Collapse
|