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Martens MD, Holody CD, Wells L, Silver HL, Morales-Llamas DY, Du WW, Reeks C, Khairy M, Chen H, Ferdaoussi M, Bourque SL, Yang BB, Ussher JR, Lemieux H, Oudit GY, Screaton RA, Dyck JRB. Reactive Oxygen Species Modulator 1 Plays an Obligate Role in Cardiomyocyte Hypertrophy. Circ Res 2024; 134:114-116. [PMID: 38018429 DOI: 10.1161/circresaha.123.323456] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2023]
Affiliation(s)
- Matthew D Martens
- Cardiovascular Research Centre (M.D.M., H.L.S., D.Y.M.-L., M.K., H.C., M.F., J.R.U., G.Y.O., J.R.B.D.), Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Canada
- Alberta Diabetes Institute (M.D.M., H.L.S., D.Y.M.-L., M.K.,.M.F., J.R.U., J.R.B.D.), Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Canada
- Women and Children's Health Research Institute (M.D.M., C.D.H., H.L.S., D.Y.M.-L., M.K., M.F., S.L.B., J.R.U., H.L., J.R.B.D.), Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Canada
- Department of Pediatrics (M.D.M., C.D.H., H.L.S., D.Y.M.-L., M.K., S.L.B., J.R.B.D.), Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Canada
| | - Claudia D Holody
- Women and Children's Health Research Institute (M.D.M., C.D.H., H.L.S., D.Y.M.-L., M.K., M.F., S.L.B., J.R.U., H.L., J.R.B.D.), Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Canada
- Department of Pediatrics (M.D.M., C.D.H., H.L.S., D.Y.M.-L., M.K., S.L.B., J.R.B.D.), Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Canada
- Department of Medicine (C.D.H., H.C., H.L., G.Y.O.), Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Canada
- Department of Anesthesiology (C.D.H., S.L.B.), Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Canada
| | - Lisa Wells
- Sunnybrook Research Institute (L.W., W.W.D., C.R., B.B.Y., R.A.S.), University of Toronto, Ontario, Canada
- Department of Biochemistry (L.W., C.R., R.A.S.), University of Toronto, Ontario, Canada
| | - Heidi L Silver
- Cardiovascular Research Centre (M.D.M., H.L.S., D.Y.M.-L., M.K., H.C., M.F., J.R.U., G.Y.O., J.R.B.D.), Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Canada
- Alberta Diabetes Institute (M.D.M., H.L.S., D.Y.M.-L., M.K.,.M.F., J.R.U., J.R.B.D.), Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Canada
- Women and Children's Health Research Institute (M.D.M., C.D.H., H.L.S., D.Y.M.-L., M.K., M.F., S.L.B., J.R.U., H.L., J.R.B.D.), Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Canada
- Department of Pediatrics (M.D.M., C.D.H., H.L.S., D.Y.M.-L., M.K., S.L.B., J.R.B.D.), Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Canada
| | - Daniela Y Morales-Llamas
- Cardiovascular Research Centre (M.D.M., H.L.S., D.Y.M.-L., M.K., H.C., M.F., J.R.U., G.Y.O., J.R.B.D.), Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Canada
- Alberta Diabetes Institute (M.D.M., H.L.S., D.Y.M.-L., M.K.,.M.F., J.R.U., J.R.B.D.), Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Canada
- Women and Children's Health Research Institute (M.D.M., C.D.H., H.L.S., D.Y.M.-L., M.K., M.F., S.L.B., J.R.U., H.L., J.R.B.D.), Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Canada
- Department of Pediatrics (M.D.M., C.D.H., H.L.S., D.Y.M.-L., M.K., S.L.B., J.R.B.D.), Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Canada
| | - William W Du
- Sunnybrook Research Institute (L.W., W.W.D., C.R., B.B.Y., R.A.S.), University of Toronto, Ontario, Canada
- Department of Laboratory Medicine and Pathobiology (W.W.D., B.B.Y.), University of Toronto, Ontario, Canada
| | - Courtney Reeks
- Sunnybrook Research Institute (L.W., W.W.D., C.R., B.B.Y., R.A.S.), University of Toronto, Ontario, Canada
- Department of Biochemistry (L.W., C.R., R.A.S.), University of Toronto, Ontario, Canada
| | - Mostafa Khairy
- Cardiovascular Research Centre (M.D.M., H.L.S., D.Y.M.-L., M.K., H.C., M.F., J.R.U., G.Y.O., J.R.B.D.), Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Canada
- Alberta Diabetes Institute (M.D.M., H.L.S., D.Y.M.-L., M.K.,.M.F., J.R.U., J.R.B.D.), Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Canada
- Women and Children's Health Research Institute (M.D.M., C.D.H., H.L.S., D.Y.M.-L., M.K., M.F., S.L.B., J.R.U., H.L., J.R.B.D.), Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Canada
- Department of Pediatrics (M.D.M., C.D.H., H.L.S., D.Y.M.-L., M.K., S.L.B., J.R.B.D.), Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Canada
| | - Huachen Chen
- Cardiovascular Research Centre (M.D.M., H.L.S., D.Y.M.-L., M.K., H.C., M.F., J.R.U., G.Y.O., J.R.B.D.), Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Canada
| | - Mourad Ferdaoussi
- Cardiovascular Research Centre (M.D.M., H.L.S., D.Y.M.-L., M.K., H.C., M.F., J.R.U., G.Y.O., J.R.B.D.), Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Canada
- Alberta Diabetes Institute (M.D.M., H.L.S., D.Y.M.-L., M.K.,.M.F., J.R.U., J.R.B.D.), Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Canada
- Women and Children's Health Research Institute (M.D.M., C.D.H., H.L.S., D.Y.M.-L., M.K., M.F., S.L.B., J.R.U., H.L., J.R.B.D.), Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Canada
- Faculty Saint-Jean (M.F., H.L.), University of Alberta, Edmonton, Canada
| | - Stephane L Bourque
- Women and Children's Health Research Institute (M.D.M., C.D.H., H.L.S., D.Y.M.-L., M.K., M.F., S.L.B., J.R.U., H.L., J.R.B.D.), Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Canada
- Department of Pediatrics (M.D.M., C.D.H., H.L.S., D.Y.M.-L., M.K., S.L.B., J.R.B.D.), Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Canada
- Department of Medicine (C.D.H., H.C., H.L., G.Y.O.), Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Canada
- Department of Anesthesiology (C.D.H., S.L.B.), Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Canada
| | - Burton B Yang
- Sunnybrook Research Institute (L.W., W.W.D., C.R., B.B.Y., R.A.S.), University of Toronto, Ontario, Canada
- Department of Laboratory Medicine and Pathobiology (W.W.D., B.B.Y.), University of Toronto, Ontario, Canada
| | - John R Ussher
- Cardiovascular Research Centre (M.D.M., H.L.S., D.Y.M.-L., M.K., H.C., M.F., J.R.U., G.Y.O., J.R.B.D.), Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Canada
- Alberta Diabetes Institute (M.D.M., H.L.S., D.Y.M.-L., M.K.,.M.F., J.R.U., J.R.B.D.), Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Canada
- Women and Children's Health Research Institute (M.D.M., C.D.H., H.L.S., D.Y.M.-L., M.K., M.F., S.L.B., J.R.U., H.L., J.R.B.D.), Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Canada
- Faculty of Pharmacy and Pharmaceutical Sciences (J.R.U.), University of Alberta, Edmonton, Canada
| | - Hélène Lemieux
- Women and Children's Health Research Institute (M.D.M., C.D.H., H.L.S., D.Y.M.-L., M.K., M.F., S.L.B., J.R.U., H.L., J.R.B.D.), Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Canada
- Department of Medicine (C.D.H., H.C., H.L., G.Y.O.), Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Canada
- Faculty Saint-Jean (M.F., H.L.), University of Alberta, Edmonton, Canada
| | - Gavin Y Oudit
- Cardiovascular Research Centre (M.D.M., H.L.S., D.Y.M.-L., M.K., H.C., M.F., J.R.U., G.Y.O., J.R.B.D.), Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Canada
- Department of Medicine (C.D.H., H.C., H.L., G.Y.O.), Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Canada
| | - Robert A Screaton
- Sunnybrook Research Institute (L.W., W.W.D., C.R., B.B.Y., R.A.S.), University of Toronto, Ontario, Canada
- Department of Biochemistry (L.W., C.R., R.A.S.), University of Toronto, Ontario, Canada
| | - Jason R B Dyck
- Cardiovascular Research Centre (M.D.M., H.L.S., D.Y.M.-L., M.K., H.C., M.F., J.R.U., G.Y.O., J.R.B.D.), Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Canada
- Alberta Diabetes Institute (M.D.M., H.L.S., D.Y.M.-L., M.K.,.M.F., J.R.U., J.R.B.D.), Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Canada
- Women and Children's Health Research Institute (M.D.M., C.D.H., H.L.S., D.Y.M.-L., M.K., M.F., S.L.B., J.R.U., H.L., J.R.B.D.), Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Canada
- Department of Pediatrics (M.D.M., C.D.H., H.L.S., D.Y.M.-L., M.K., S.L.B., J.R.B.D.), Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Canada
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Chatterjee P, Holody CD, Kirschenman R, Graton ME, Spaans F, Phillips TJ, Case CP, Bourque SL, Lemieux H, Davidge ST. Sex-Specific Effects of Prenatal Hypoxia and a Placental Antioxidant Treatment on Cardiac Mitochondrial Function in the Young Adult Offspring. Int J Mol Sci 2023; 24:13624. [PMID: 37686430 PMCID: PMC10487956 DOI: 10.3390/ijms241713624] [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: 07/17/2023] [Revised: 08/25/2023] [Accepted: 09/01/2023] [Indexed: 09/10/2023] Open
Abstract
Prenatal hypoxia is associated with placental oxidative stress, leading to impaired fetal growth and an increased risk of cardiovascular disease in the adult offspring; however, the mechanisms are unknown. Alterations in mitochondrial function may result in impaired cardiac function in offspring. In this study, we hypothesized that cardiac mitochondrial function is impaired in adult offspring exposed to intrauterine hypoxia, which can be prevented by placental treatment with a nanoparticle-encapsulated mitochondrial antioxidant (nMitoQ). Cardiac mitochondrial respiration was assessed in 4-month-old rat offspring exposed to prenatal hypoxia (11% O2) from gestational day (GD)15-21 receiving either saline or nMitoQ on GD 15. Prenatal hypoxia did not alter cardiac mitochondrial oxidative phosphorylation capacity in the male offspring. In females, the NADH + succinate pathway capacity decreased by prenatal hypoxia and tended to be increased by nMitoQ. Prenatal hypoxia also decreased the succinate pathway capacity in females. nMitoQ treatment increased respiratory coupling efficiency in prenatal hypoxia-exposed female offspring. In conclusion, prenatal hypoxia impaired cardiac mitochondrial function in adult female offspring only, which was improved with prenatal nMitoQ treatment. Therefore, treatment strategies targeting placental oxidative stress in prenatal hypoxia may reduce the risk of cardiovascular disease in adult offspring by improving cardiac mitochondrial function in a sex-specific manner.
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Affiliation(s)
- Paulami Chatterjee
- Department of Physiology, University of Alberta, Edmonton, AB T6G 2R3, Canada;
- Department of Obstetrics and Gynecology, University of Alberta, Edmonton, AB T6G 2R3, Canada; (R.K.); (M.E.G.); (F.S.)
- Women and Children’s Health Research Institute, University of Alberta, Edmonton, AB T6G 2R3, Canada; (S.L.B.); (H.L.)
| | - Claudia D. Holody
- Faculty Saint-Jean, University of Alberta, Edmonton, AB T6G 2R3, Canada;
- Department of Pediatrics, University of Alberta, Edmonton, AB T6G 2R3, Canada
| | - Raven Kirschenman
- Department of Obstetrics and Gynecology, University of Alberta, Edmonton, AB T6G 2R3, Canada; (R.K.); (M.E.G.); (F.S.)
- Women and Children’s Health Research Institute, University of Alberta, Edmonton, AB T6G 2R3, Canada; (S.L.B.); (H.L.)
| | - Murilo E. Graton
- Department of Obstetrics and Gynecology, University of Alberta, Edmonton, AB T6G 2R3, Canada; (R.K.); (M.E.G.); (F.S.)
- Women and Children’s Health Research Institute, University of Alberta, Edmonton, AB T6G 2R3, Canada; (S.L.B.); (H.L.)
| | - Floor Spaans
- Department of Obstetrics and Gynecology, University of Alberta, Edmonton, AB T6G 2R3, Canada; (R.K.); (M.E.G.); (F.S.)
- Women and Children’s Health Research Institute, University of Alberta, Edmonton, AB T6G 2R3, Canada; (S.L.B.); (H.L.)
| | - Tom J. Phillips
- UK Dementia Research Institute, Cardiff University, Cardiff CF10 3AT, UK;
| | - C. Patrick Case
- Musculoskeletal Research Unit, University of Bristol, Bristol BS10 5NB, UK;
| | - Stephane L. Bourque
- Women and Children’s Health Research Institute, University of Alberta, Edmonton, AB T6G 2R3, Canada; (S.L.B.); (H.L.)
- Department of Pediatrics, University of Alberta, Edmonton, AB T6G 2R3, Canada
- Department of Anesthesiology & Pain Medicine, University of Alberta, Edmonton, AB T6G 2R3, Canada
| | - Hélène Lemieux
- Women and Children’s Health Research Institute, University of Alberta, Edmonton, AB T6G 2R3, Canada; (S.L.B.); (H.L.)
- Faculty Saint-Jean, University of Alberta, Edmonton, AB T6G 2R3, Canada;
- Department of Medicine, University of Alberta, Edmonton, AB T6G 2R3, Canada
| | - Sandra T. Davidge
- Department of Physiology, University of Alberta, Edmonton, AB T6G 2R3, Canada;
- Department of Obstetrics and Gynecology, University of Alberta, Edmonton, AB T6G 2R3, Canada; (R.K.); (M.E.G.); (F.S.)
- Women and Children’s Health Research Institute, University of Alberta, Edmonton, AB T6G 2R3, Canada; (S.L.B.); (H.L.)
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Bassot A, Chen J, Takahashi-Yamashiro K, Yap MC, Gibhardt CS, Le GNT, Hario S, Nasu Y, Moore J, Gutiérrez T, Mina L, Mast H, Moses A, Bhat R, Ballanyi K, Lemieux H, Sitia R, Zito E, Bogeski I, Campbell RE, Simmen T. The endoplasmic reticulum kinase PERK interacts with the oxidoreductase ERO1 to metabolically adapt mitochondria. Cell Rep 2023; 42:111899. [PMID: 36586409 DOI: 10.1016/j.celrep.2022.111899] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [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: 04/06/2022] [Revised: 10/04/2022] [Accepted: 12/08/2022] [Indexed: 12/31/2022] Open
Abstract
Endoplasmic reticulum (ER) homeostasis requires molecular regulators that tailor mitochondrial bioenergetics to the needs of protein folding. For instance, calnexin maintains mitochondria metabolism and mitochondria-ER contacts (MERCs) through reactive oxygen species (ROS) from NADPH oxidase 4 (NOX4). However, induction of ER stress requires a quick molecular rewiring of mitochondria to adapt to new energy needs. This machinery is not characterized. We now show that the oxidoreductase ERO1⍺ covalently interacts with protein kinase RNA-like ER kinase (PERK) upon treatment with tunicamycin. The PERK-ERO1⍺ interaction requires the C-terminal active site of ERO1⍺ and cysteine 216 of PERK. Moreover, we show that the PERK-ERO1⍺ complex promotes oxidization of MERC proteins and controls mitochondrial dynamics. Using proteinaceous probes, we determined that these functions improve ER-mitochondria Ca2+ flux to maintain bioenergetics in both organelles, while limiting oxidative stress. Therefore, the PERK-ERO1⍺ complex is a key molecular machinery that allows quick metabolic adaptation to ER stress.
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Affiliation(s)
- Arthur Bassot
- Department of Cell Biology, Faculty of Medicine and Dentistry, Edmonton, AB T6G 2G2, Canada
| | - Junsheng Chen
- Department of Cell Biology, Faculty of Medicine and Dentistry, Edmonton, AB T6G 2G2, Canada
| | | | - Megan C Yap
- Department of Cell Biology, Faculty of Medicine and Dentistry, Edmonton, AB T6G 2G2, Canada
| | - Christine Silvia Gibhardt
- Molecular Physiology, Institute of Cardiovascular Physiology, University Medical Center, Georg-August-University, Göttingen, Germany
| | - Giang N T Le
- Department of Chemistry, Graduate School of Science, The University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Saaya Hario
- Department of Chemistry, Graduate School of Science, The University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Yusuke Nasu
- Department of Chemistry, Graduate School of Science, The University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Jack Moore
- Alberta Proteomics and Mass Spectrometry Facility, University of Alberta, 4096 Katz Research Building, Edmonton AB T6G2E1, Canada
| | - Tomas Gutiérrez
- Department of Cell Biology, Faculty of Medicine and Dentistry, Edmonton, AB T6G 2G2, Canada
| | - Lucas Mina
- Department of Cell Biology, Faculty of Medicine and Dentistry, Edmonton, AB T6G 2G2, Canada
| | - Heather Mast
- Faculty Saint-Jean, Department of Medicine, Faculty of Medicine and Dentistry, Edmonton, AB T6G2H7, Canada
| | - Audric Moses
- Department of Pediatrics, Edmonton, AB T6G2H7, Canada
| | - Rakesh Bhat
- Precision Biolaboratories, St. Albert, AB T8N 5A7, Canada
| | - Klaus Ballanyi
- Department of Physiology, University of Alberta, Edmonton, AB T6G2H7, Canada
| | - Hélène Lemieux
- Faculty Saint-Jean, Department of Medicine, Faculty of Medicine and Dentistry, Edmonton, AB T6G2H7, Canada
| | - Roberto Sitia
- Division of Genetics and Cell Biology, Università Vita-Salute IRCCS Ospedale San Raffaele, 20132 Milano, Italy
| | - Ester Zito
- Istituto di Ricerche Farmacologiche Mario Negri, 20156 Milano, Italy; Department of Biomolecular Sciences, University of Urbino Carlo Bo, 61029 Urbino PU, Italy
| | - Ivan Bogeski
- Molecular Physiology, Institute of Cardiovascular Physiology, University Medical Center, Georg-August-University, Göttingen, Germany
| | - Robert E Campbell
- Department of Chemistry, University of Alberta, Edmonton, AB T6G 2G2, Canada; Department of Chemistry, Graduate School of Science, The University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Thomas Simmen
- Department of Cell Biology, Faculty of Medicine and Dentistry, Edmonton, AB T6G 2G2, Canada.
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Mast H, Holody CD, Lemieux H. Fatty acid oxidation: A neglected factor in understanding the adjustment of mitochondrial function to cold temperatures. J Exp Biol 2022; 225:278443. [PMID: 36268766 DOI: 10.1242/jeb.244934] [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: 08/31/2022] [Accepted: 10/17/2022] [Indexed: 11/20/2022]
Abstract
For ectothermic species, adaptation to thermal changes is of critical importance. Mitochondrial oxidative phosphorylation (OXPHOS), which leverages multiple electron pathways to produce energy needed for survival, is among the crucial metabolic processes impacted by temperature. Our aim in this study was to identify how changes in temperature affect the less-studied electron transferring flavoprotein pathway, fed by fatty acid substrates. We used the planarian, Dugesia tigrina, acclimated for four weeks at 10 (cold-acclimated) or 20°C (normothermic). Respirometry experiments were conducted at either 10 or 20°C assay temperatures to study specific states of the OXPHOS process using the fatty acid substrates palmitoylcarnitine (long-chain), octanoylcarnitine (medium-chain), or acetylcarnitine (short-chain). Following cold acclimation, octanoylcarnitine exhibited increases in both the OXPHOS and ET (electron transfer, noncoupled) states, indicating that the pathway involved in medium-chain length fatty acids adjusts to cold temperatures. Acetylcarnitine only showed an increase in the OXPHOS state due to cold acclimation, but not in the ET state, indicative of a change in phosphorylation system capacity rather than fatty acid β-oxidation. Palmitoylcarnitine oxidation was unaffected. Our results show that cold acclimation in D. tigrina caused a specific adjustment in the capacity to metabolize medium-chain fatty acid rather than an adjustment in the activity of enzymes carnitine-acylcarnitine translocase, carnitine acyltransferase, and carnitine palmitoyltransferase-2. Here, we provide novel evidence of the alterations in fatty acid β-oxidation during cold acclimation in D. tigrina.
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Affiliation(s)
- Heather Mast
- Faculty Saint-Jean, Women and Children Research Health Institute, Dept. of Medicine, Dept. of Pediatrics, University of Alberta, Edmonton, Alberta, Canada
| | - Claudia D Holody
- Faculty Saint-Jean, Women and Children Research Health Institute, Dept. of Medicine, Dept. of Pediatrics, University of Alberta, Edmonton, Alberta, Canada
| | - Hélène Lemieux
- Faculty Saint-Jean, Women and Children Research Health Institute, Dept. of Medicine, Dept. of Pediatrics, University of Alberta, Edmonton, Alberta, Canada
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Abstract
INTRODUCTION The impact of eccentric exercise on mitochondrial function has only been poorly investigated and remains unclear. This study aimed to identify the changes in skeletal muscle mitochondrial respiration, specifically triggered by a single bout of eccentric treadmill exercise. METHODS Male adult mice were randomly divided into eccentric (ECC; downhill running), concentric (CON; uphill running), and unexercised control groups ( n = 5/group). Running groups performed 18 bouts of 5 min at 20 cm·s -1 on an inclined treadmill (±15° to 20°). Mice were sacrificed 48 h after exercise for blood and quadriceps muscles collection. Deep proximal (red) and superficial distal (white) muscle portions were used for high-resolution respirometric measurements. RESULTS Plasma creatine kinase activity was significantly higher in the ECC compared with CON group, reflecting exercise-induced muscle damage ( P < 0.01). The ECC exercise induced a significant decrease in oxidative phosphorylation capacity in both quadriceps femoris parts ( P = 0.032 in proximal portion, P = 0.010 in distal portion) in comparison with the CON group. This observation was only made for the nicotinamide adenine dinucleotide (NADH) pathway using pyruvate + malate as substrates. When expressed as a flux control ratio, indicating a change related to mitochondrial quality rather than quantity, this change seemed more prominent in distal compared with proximal portion of quadriceps muscle. No significant difference between groups was found for the NADH pathway with glutamate or glutamate + malate as substrates, for the succinate pathway or for fatty acid oxidation. CONCLUSIONS Our data suggest that ECC exercise specifically affects pyruvate mitochondrial transport and/or oxidation 48 h after exercise, and this alteration mainly concerns the distal white muscle portion. This study provides new perspectives to improve our understanding of the mitochondrial adaptation associated with ECC exercise.
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Affiliation(s)
- Stéphanie Hody
- Department of Motricity Sciences, University of Liège, Liège, BELGIUM
| | - Blair E Warren
- Faculty Saint-Jean, University of Alberta, Edmonton, Alberta, CANADA
| | - Dominique-Marie Votion
- Equine Pole, Fundamental and Applied Research for Animals & Health (FARAH), Faculty of Veterinary Medicine, Liège, BELGIUM
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Lemieux H, Blier PU. Exploring Thermal Sensitivities and Adaptations of Oxidative Phosphorylation Pathways. Metabolites 2022; 12:metabo12040360. [PMID: 35448547 PMCID: PMC9025460 DOI: 10.3390/metabo12040360] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [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: 03/22/2022] [Revised: 04/08/2022] [Accepted: 04/11/2022] [Indexed: 12/20/2022] Open
Abstract
Temperature shifts are a major challenge to animals; they drive adaptations in organisms and species, and affect all physiological functions in ectothermic organisms. Understanding the origin and mechanisms of these adaptations is critical for determining whether ectothermic organisms will be able to survive when faced with global climate change. Mitochondrial oxidative phosphorylation is thought to be an important metabolic player in this regard, since the capacity of the mitochondria to produce energy greatly varies according to temperature. However, organism survival and fitness depend not only on how much energy is produced, but, more precisely, on how oxidative phosphorylation is affected and which step of the process dictates thermal sensitivity. These questions need to be addressed from a new perspective involving a complex view of mitochondrial oxidative phosphorylation and its related pathways. In this review, we examine the effect of temperature on the commonly measured pathways, but mainly focus on the potential impact of lesser-studied pathways and related steps, including the electron-transferring flavoprotein pathway, glycerophosphate dehydrogenase, dihydroorotate dehydrogenase, choline dehydrogenase, proline dehydrogenase, and sulfide:quinone oxidoreductase. Our objective is to reveal new avenues of research that can address the impact of temperature on oxidative phosphorylation in all its complexity to better portray the limitations and the potential adaptations of aerobic metabolism.
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Affiliation(s)
- Hélène Lemieux
- Faculty Saint-Jean, Department of Medicine, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB T6C 4G9, Canada
- Correspondence: (H.L.); (P.U.B.)
| | - Pierre U. Blier
- Department Biologie, Université du Québec à Rimouski, Rimouski, QC G5L 3A1, Canada
- Correspondence: (H.L.); (P.U.B.)
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Pages N, Picard F, Barritault F, Amara W, Lafitte S, Maribas P, Abassade P, Labarre JP, Boulestreau R, Chaouky H, Abdennadher M, Lemieux H, Lasserre R, Bedel C, Betito L, Nisse-Durgeat S, Diebold B. Remote patient monitoring for chronic heart failure in France: When an innovative funding program (ETAPES) meets an innovative solution (Satelia® Cardio). Digit Health 2022; 8:20552076221116774. [PMID: 36034602 PMCID: PMC9403459 DOI: 10.1177/20552076221116774] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [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: 03/03/2022] [Accepted: 07/13/2022] [Indexed: 11/15/2022] Open
Abstract
Introduction Remote patient monitoring (RPM) is a telehealth activity to collect and analyze patient health or medical data. Its use has expanded in the past decade and has improved medical outcomes and care management of non-communicable chronic diseases. However, implementation of RPM into routine clinical activities has been limited. The objective of this study was to describe the French funding program for RPM (known as ETAPES) and one of the RPM solution providers (Satelia®) dedicated to chronic heart failure (CHF). Methods A descriptive assessment of both the ETAPES funding program and Satelia® RPM solution was conducted. Data were collected from official legal documents and information that was publicly available online from the French Ministry of Health. Results and Discussion ETAPES was formally created in 2016 based on previous legislation pertaining to the national health insurance funding strategy. However, it only started to operate in 2018. Patients with CHF were only eligible if they were at medium or high risk of re-hospitalization with a New York Heart Association (NYHA) score superior or equal to two and a BNP>100 pg/ml or NT pro BNP>1000 pg/ml. Medical monitoring was supported through the therapeutic education of a patient on the RPM model of care with a minimum of three training sessions during the first six months. The use of Satelia® Cardio is noteworthy since it relies only on symptomatic monitoring through which the patient manually reports their information by answering a simple questionnaire on a regular basis and does not rely on any connected devices. Conclusion Innovative funding programs and solutions for RPM need real-world evaluation in the future.
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Affiliation(s)
- N Pages
- Cardiology Department, Hôpital Haut Leveque, Pessac, France
| | - F Picard
- Cardiology Department, Hôpital Haut Leveque, Pessac, France
| | - F Barritault
- Cardiology Department, GCS Cardiologie, Hôpital de Bayonne, Bayonne, France
| | - W Amara
- Cardiology Department, Centre Hospitalier Intercommunal Le Raincy-Montfermeil, Le Raincy-Montfermeil, France
| | - S Lafitte
- Cardiology Department, Hôpital Haut Leveque, Pessac, France
| | - P Maribas
- Cardiology Department, Hôpital privé de Parly 2, Le Chesnay, France
| | - P Abassade
- Cardiology Department, Hôpital Saint Joseph, Paris, France
| | - J Ph Labarre
- Cardiology Department, Clinique du Pont de Chaume, Montauban,
France
| | - R Boulestreau
- Cardiology Department, Centre Hospitalier de Pau, Pau, France
| | - H Chaouky
- Cardiology Department, Centre Hospitalier de Pau, Pau, France
| | - M Abdennadher
- Cardiology Department, Centre Hospitalier de Bigorre, Tarbes,
France
| | - H Lemieux
- Cardiology Department, Clinique Esquirol St Hilaire, Agen, France
| | - R Lasserre
- Cardiology Department, Centre Hospitalier de Bigorre, Tarbes,
France
| | - C Bedel
- NP Medical, Bordeaux, France
| | | | | | - B Diebold
- Cardiology Department, Hôpital Cochin, Paris, France
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8
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Rodríguez E, Hakkou M, Hagen TM, Lemieux H, Blier PU. Divergences in the Control of Mitochondrial Respiration Are Associated With Life-Span Variation in Marine Bivalves. J Gerontol A Biol Sci Med Sci 2021; 76:796-804. [PMID: 33257932 DOI: 10.1093/gerona/glaa301] [Citation(s) in RCA: 6] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Indexed: 12/31/2022] Open
Abstract
The role played by mitochondrial function in the aging process has been a subject of intense debate in the past few decades, as part of the efforts to understand the mechanistic basis of longevity. The mitochondrial oxidative stress theory of aging suggests that a progressive decay of this organelle's function leads to an exacerbation of oxidative stress, with a deleterious impact on mitochondrial structure and DNA, ultimately promoting aging. Among the traits suspected to be associated with longevity is the variation in the regulation of oxidative phosphorylation, potentially affecting the management of oxidative stress. Longitudinal studies using the framework of metabolic control analysis have shown age-related differences in the flux control of respiration, but this approach has seldom been taken on a comparative scale. Using 4 species of marine bivalves exhibiting a large range of maximum life span (from 28 years to 507 years), we report life-span-related differences in flux control at different steps of the electron transfer system. Increased longevity was characterized by a lower control by NADH (complex I-linked) and Succinate (complex II-linked) pathways, while respiration was strongly controlled by complex IV when compared to shorter-lived species. Complex III exerted strong control over respiration in all species. Furthermore, high longevity was associated with higher citrate synthase activity and lower ATP synthase activity. Relieving the control exerted by the electron entry pathways could be advantageous for reaching higher longevity, leading to increased control by complex IV, the final electron acceptor in the electron transfer system.
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Affiliation(s)
- Enrique Rodríguez
- Département de Biologie, Université du Québec, Rimouski, Québec, Canada
| | - Mohammed Hakkou
- Département de Biologie, Université du Québec, Rimouski, Québec, Canada
| | - Tory M Hagen
- Linus Pauling Institute, Oregon State University, Corvallis, Oregon, USA
| | - Hélène Lemieux
- Faculty Saint-Jean, Department of Medicine, Women and Children Health Research Institute, University of Alberta, Edmonton, Alberta, Canada
| | - Pierre U Blier
- Département de Biologie, Université du Québec, Rimouski, Québec, Canada
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9
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Lemieux H, Picard F, Barritault F, Labarre J, Lafitte S, Maribas P, Chaouky H, Abdennadher M, Lasserre R, Amara W, Pages N, Nisse-Durgeat S, Diebold B. First experience with a ready-to-use solution for remote monitoring of patients suffering from heart failure. Eur J Prev Cardiol 2021. [PMCID: PMC8136073 DOI: 10.1093/eurjpc/zwab061.434] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Funding Acknowledgements Type of funding sources: None. Background Heart failure (HF) is associated with a high mortality rate and recurrent hospitalizations. Purpose To present the first data of the patients using Satelia® Cardio solution Method Satelia® Cardio is a HF patient management solution with a remote monitoring system and a therapeutic guidance by a dedicated-nurse phone platform, supported by the ETAPES Program. The system is accessible from any device and requiring no installation. After the inclusion, the patient is contacted by the nurse, he then receives an SMS alerts following cardiologist prescription (on regular basis), with a link leading to a web page on which he will answer 7 questions and enter his current body weight. Satelia® Cardio algorithm is based on these data inputs, their variability, and the weight. In case of worsening of symptoms, the cardiologist will be notified. Since Covid-19 lockdown, more than 1400 patients have been monitored with the solution. Results 165 centers (306 cardiologists) are using Satelia® Cardio with 3540 HF patients monitored in the last 29 months. The patients with a mean age of 72 years (19-100) are predominantly males (67%), and mostly NYHA II/III (69%/31%) with a mean LVEF of 40%. The adherence to the system is very good (91%) with 78% of patients still monitored (n = 2787). The main reasons for stopping are related to the occurrence of death (205/753) or patient/HCP decision (392/753), or other reasons (156/753). Over the period of analysis, the HF patients answered to 163 700 questionnaires, generating 8210 alerts transmitted to the referent cardiologists. Conclusion Patient management solution with a remote monitoring system is key to improving the follow-up of HF patients. The solution Satelia® Cardio is an easy way to use a web application to monitor HF patients, especially on the current period of Covid-19 with a low rate of premature discontinuation. A further step will be to initiate studies to assess the potential benefits for both patients and HCPs of such remote monitoring solution in HF.
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Affiliation(s)
- H Lemieux
- CLINIC ESQUIROL-SAINT-HILAIRE, Agen, France
| | - F Picard
- Hospital Haut Leveque, Cardiology, Bordeaux, France
| | | | - J Labarre
- Clinique du Pont de Chaume, Montauban, France
| | - S Lafitte
- Hospital Haut Leveque, Cardiology, Bordeaux, France
| | - P Maribas
- Private Hopital of Parly II, Le Chesnay, France
| | | | | | - R Lasserre
- Centre Hospitalier de Bigorre, Tarbes, France
| | - W Amara
- Centre Hospitalier Intercommunal Le Raincy-Montfermeil, Cardiology, Le Raincy-Montfermeil, France
| | - N Pages
- Hospital Haut Leveque, Cardiology, Bordeaux, France
| | | | - B Diebold
- COCHIN APHP SITE OF PARIS CENTRE UNIVERSITY HOSPITAL, Paris, France
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10
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Ganguly E, Kirschenman R, Spaans F, Holody CD, Phillips TEJ, Case CP, Cooke CLM, Murphy MP, Lemieux H, Davidge ST. Nanoparticle-encapsulated antioxidant improves placental mitochondrial function in a sexually dimorphic manner in a rat model of prenatal hypoxia. FASEB J 2021; 35:e21338. [PMID: 33428278 DOI: 10.1096/fj.202002193r] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Revised: 12/11/2020] [Accepted: 12/17/2020] [Indexed: 12/12/2022]
Abstract
Pregnancy complications associated with prenatal hypoxia lead to increased placental oxidative stress. Previous studies suggest that prenatal hypoxia can reduce mitochondrial respiratory capacity and mitochondrial fusion, which could lead to placental dysfunction and impaired fetal development. We developed a placenta-targeted treatment strategy using a mitochondrial antioxidant, MitoQ, encapsulated into nanoparticles (nMitoQ) to reduce placental oxidative stress and (indirectly) improve fetal outcomes. We hypothesized that, in a rat model of prenatal hypoxia, nMitoQ improves placental mitochondrial function and promotes mitochondrial fusion in both male and female placentae. Pregnant rats were treated with saline or nMitoQ on gestational day (GD) 15 and exposed to normoxia (21% O2 ) or hypoxia (11% O2 ) from GD15-21. On GD21, male and female placental labyrinth zones were collected for mitochondrial respirometry assessments, mitochondrial content, and markers of mitochondrial biogenesis, fusion and fission. Prenatal hypoxia reduced complex IV activity and fusion in male placentae, while nMitoQ improved complex IV activity in hypoxic male placentae. In female placentae, prenatal hypoxia decreased respiration through the S-pathway (complex II) and increased N-pathway (complex I) respiration, while nMitoQ increased fusion in hypoxic female placentae. No changes in mitochondrial content, biogenesis or fission were found. In conclusion, nMitoQ improved placental mitochondrial function in male and female placentae from fetuses exposed to prenatal hypoxia, which may contribute to improved placental function. However, the mechanisms (ie, changes in mitochondrial respiratory capacity and mitochondrial fusion) were distinct between the sexes. Treatment strategies targeted against placental oxidative stress could improve placental mitochondrial function in complicated pregnancies.
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Affiliation(s)
- Esha Ganguly
- Department of Physiology, University of Alberta, Edmonton, AB, Canada.,Department of Obstetrics and Gynaecology, University of Alberta, Edmonton, AB, Canada.,Women and Children's Health Research Institute, University of Alberta, Edmonton, AB, Canada
| | - Raven Kirschenman
- Department of Obstetrics and Gynaecology, University of Alberta, Edmonton, AB, Canada.,Women and Children's Health Research Institute, University of Alberta, Edmonton, AB, Canada
| | - Floor Spaans
- Department of Obstetrics and Gynaecology, University of Alberta, Edmonton, AB, Canada.,Women and Children's Health Research Institute, University of Alberta, Edmonton, AB, Canada
| | - Claudia D Holody
- Women and Children's Health Research Institute, University of Alberta, Edmonton, AB, Canada.,Department of Paediatrics, University of Alberta, Edmonton, AB, Canada.,Faculty Saint-Jean, University of Alberta, Edmonton, AB, Canada
| | | | - C Patrick Case
- Musculoskeletal Research Unit, University of Bristol, Bristol, UK
| | - Christy-Lynn M Cooke
- Department of Obstetrics and Gynaecology, University of Alberta, Edmonton, AB, Canada.,Women and Children's Health Research Institute, University of Alberta, Edmonton, AB, Canada
| | - Michael P Murphy
- MRC Mitochondrial Biology Unit, Keith Peters Building, University of Cambridge, Cambridge, UK
| | - Hélène Lemieux
- Women and Children's Health Research Institute, University of Alberta, Edmonton, AB, Canada.,Faculty Saint-Jean, University of Alberta, Edmonton, AB, Canada.,Department of Medicine, University of Alberta, Edmonton, AB, Canada
| | - Sandra T Davidge
- Department of Physiology, University of Alberta, Edmonton, AB, Canada.,Department of Obstetrics and Gynaecology, University of Alberta, Edmonton, AB, Canada.,Women and Children's Health Research Institute, University of Alberta, Edmonton, AB, Canada
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11
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Picard F, Barritault F, Amara W, Lafitte S, Maribas P, Abassade P, Labarre J, Boulestreau R, Chaouky H, Jagu A, Abdennadher M, Lemieux H, Lasserre R, Pages N, Nisse-Durgeat S, Diebold B. First experience with a ready to use solution for remote monitoring of patients suffering from heart failure in France. Archives of Cardiovascular Diseases Supplements 2021. [DOI: 10.1016/j.acvdsp.2020.10.090] [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: 11/16/2022]
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12
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Holody C, Anfray A, Mast H, Lessard M, Han WH, Carpenter R, Bourque S, Sauvé Y, Lemieux H. Differences in relative capacities of oxidative phosphorylation pathways may explain sex- and tissue-specific susceptibility to vision defects due to mitochondrial dysfunction. Mitochondrion 2020; 56:102-110. [PMID: 33271347 DOI: 10.1016/j.mito.2020.11.013] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [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: 07/21/2020] [Revised: 10/09/2020] [Accepted: 11/18/2020] [Indexed: 01/03/2023]
Abstract
Mitochondrial dysfunction is a major cause and/or contributor to the development and progression of vision defects in many ophthalmologic and mitochondrial diseases. Despite their mechanistic commonality, these diseases exhibit an impressive variety in sex- and tissue-specific penetrance, incidence, and severity. Currently, there is no functional explanation for these differences. We measured the function, relative capacities, and patterns of control of various oxidative phosphorylation pathways in the retina, the eyecup, the extraocular muscles, the optic nerve, and the sciatic nerve of adult male and female rats. We show that the control of mitochondrial respiratory pathways in the visual system is sex- and tissue-specific and that this may be an important factor in determining susceptibility to mitochondrial dysfunction between these groups. The optic nerve showed a low relative capacity of the NADH pathway, depending on complex I, compared to other tissues relying mainly on mitochondria for energy production. Furthermore, NADH pathway capacity is higher in females compared to males, and this sexual dimorphism occurs only in the optic nerve. Our results propose an explanation for Leber's hereditary optic neuropathy, a mitochondrial disease more prevalent in males where the principal tissue affected is the optic nerve. To our knowledge, this is the first study to identify and provide functional explanations for differences in the occurrence and severity of visual defects between tissues and between sexes. Our results highlight the importance of considering sex- and tissue-specific mitochondrial function in elucidating pathophysiological mechanisms of visual defects.
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Affiliation(s)
- Claudia Holody
- Faculty Saint-Jean, University of Alberta, Edmonton, Alberta, Canada; Dept. of Pediatrics, University of Alberta, Edmonton, Alberta, Canada; Women and Children Research Health Institute, University of Alberta, Edmonton, Alberta, Canada; Dept. of Anesthesiology & Pain Medicine, University of Alberta, Edmonton, Alberta, Canada
| | - Anaïs Anfray
- Faculty Saint-Jean, University of Alberta, Edmonton, Alberta, Canada
| | - Heather Mast
- Faculty Saint-Jean, University of Alberta, Edmonton, Alberta, Canada
| | - Martin Lessard
- Faculty Saint-Jean, University of Alberta, Edmonton, Alberta, Canada
| | - Woo Hyun Han
- Faculty Saint-Jean, University of Alberta, Edmonton, Alberta, Canada
| | - Rowan Carpenter
- Faculty Saint-Jean, University of Alberta, Edmonton, Alberta, Canada
| | - Stephane Bourque
- Dept. of Pediatrics, University of Alberta, Edmonton, Alberta, Canada; Women and Children Research Health Institute, University of Alberta, Edmonton, Alberta, Canada; Dept. of Anesthesiology & Pain Medicine, University of Alberta, Edmonton, Alberta, Canada
| | - Yves Sauvé
- Dept. of Ophthalmology and Visual Sciences, University of Alberta, Edmonton, Alberta, Canada
| | - Hélène Lemieux
- Faculty Saint-Jean, University of Alberta, Edmonton, Alberta, Canada; Women and Children Research Health Institute, University of Alberta, Edmonton, Alberta, Canada; Dept. of Medicine, University of Alberta, Edmonton, Alberta, Canada.
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13
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Liu RZ, Choi WS, Jain S, Dinakaran D, Xu X, Han WH, Yang XH, Glubrecht DD, Moore RB, Lemieux H, Godbout R. The FABP12/PPARγ pathway promotes metastatic transformation by inducing epithelial-to-mesenchymal transition and lipid-derived energy production in prostate cancer cells. Mol Oncol 2020; 14:3100-3120. [PMID: 33031638 PMCID: PMC7718947 DOI: 10.1002/1878-0261.12818] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [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: 05/15/2020] [Revised: 08/11/2020] [Accepted: 10/05/2020] [Indexed: 12/31/2022] Open
Abstract
Early stage localized prostate cancer (PCa) has an excellent prognosis; however, patient survival drops dramatically when PCa metastasizes. The molecular mechanisms underlying PCa metastasis are complex and remain unclear. Here, we examine the role of a new member of the fatty acid‐binding protein (FABP) family, FABP12, in PCa progression. FABP12 is preferentially amplified and/or overexpressed in metastatic compared to primary tumors from both PCa patients and xenograft animal models. We show that FABP12 concurrently triggers metastatic phenotypes (induced epithelial‐to‐mesenchymal transition (EMT) leading to increased cell motility and invasion) and lipid bioenergetics (increased fatty acid uptake and accumulation, increased ATP production from fatty acid β‐oxidation) in PCa cells, supporting increased reliance on fatty acids for energy production. Mechanistically, we show that FABP12 is a driver of PPARγ activation which, in turn, regulates FABP12's role in lipid metabolism and PCa progression. Our results point to a novel role for a FABP‐PPAR pathway in promoting PCa metastasis through induction of EMT and lipid bioenergetics.
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Affiliation(s)
- Rong-Zong Liu
- Department of Oncology, Cross Cancer Institute, University of Alberta, Edmonton, AB, Canada
| | - Won-Shik Choi
- Department of Oncology, Cross Cancer Institute, University of Alberta, Edmonton, AB, Canada
| | - Saket Jain
- Department of Oncology, Cross Cancer Institute, University of Alberta, Edmonton, AB, Canada
| | - Deepak Dinakaran
- Department of Oncology, Cross Cancer Institute, University of Alberta, Edmonton, AB, Canada
| | - Xia Xu
- Department of Oncology, Cross Cancer Institute, University of Alberta, Edmonton, AB, Canada
| | - Woo Hyun Han
- Faculty Saint-Jean, University of Alberta, Edmonton, AB, Canada
| | - Xiao-Hong Yang
- Department of Oncology, Cross Cancer Institute, University of Alberta, Edmonton, AB, Canada
| | - Darryl D Glubrecht
- Department of Oncology, Cross Cancer Institute, University of Alberta, Edmonton, AB, Canada
| | - Ronald B Moore
- Department of Oncology, Cross Cancer Institute, University of Alberta, Edmonton, AB, Canada.,Department of Surgery, University of Alberta, Edmonton, AB, Canada
| | - Hélène Lemieux
- Faculty Saint-Jean, University of Alberta, Edmonton, AB, Canada
| | - Roseline Godbout
- Department of Oncology, Cross Cancer Institute, University of Alberta, Edmonton, AB, Canada
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14
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Makrecka‐Kuka M, Liepinsh E, Murray AJ, Lemieux H, Dambrova M, Tepp K, Puurand M, Käämbre T, Han WH, Goede P, O'Brien KA, Turan B, Tuncay E, Olgar Y, Rolo AP, Palmeira CM, Boardman NT, Wüst RCI, Larsen TS. Altered mitochondrial metabolism in the insulin-resistant heart. Acta Physiol (Oxf) 2020; 228:e13430. [PMID: 31840389 DOI: 10.1111/apha.13430] [Citation(s) in RCA: 51] [Impact Index Per Article: 12.8] [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: 08/16/2019] [Revised: 12/05/2019] [Accepted: 12/06/2019] [Indexed: 12/12/2022]
Abstract
Obesity-induced insulin resistance and type 2 diabetes mellitus can ultimately result in various complications, including diabetic cardiomyopathy. In this case, cardiac dysfunction is characterized by metabolic disturbances such as impaired glucose oxidation and an increased reliance on fatty acid (FA) oxidation. Mitochondrial dysfunction has often been associated with the altered metabolic function in the diabetic heart, and may result from FA-induced lipotoxicity and uncoupling of oxidative phosphorylation. In this review, we address the metabolic changes in the diabetic heart, focusing on the loss of metabolic flexibility and cardiac mitochondrial function. We consider the alterations observed in mitochondrial substrate utilization, bioenergetics and dynamics, and highlight new areas of research which may improve our understanding of the cause and effect of cardiac mitochondrial dysfunction in diabetes. Finally, we explore how lifestyle (nutrition and exercise) and pharmacological interventions can prevent and treat metabolic and mitochondrial dysfunction in diabetes.
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Affiliation(s)
| | | | - Andrew J. Murray
- Department of Physiology, Development and Neuroscience University of Cambridge Cambridge UK
| | - Hélène Lemieux
- Department of Medicine Faculty Saint‐Jean, Women and Children's Health Research Institute University of Alberta Edmonton AB Canada
| | | | - Kersti Tepp
- National Institute of Chemical Physics and Biophysics Tallinn Estonia
| | - Marju Puurand
- National Institute of Chemical Physics and Biophysics Tallinn Estonia
| | - Tuuli Käämbre
- National Institute of Chemical Physics and Biophysics Tallinn Estonia
| | - Woo H. Han
- Faculty Saint‐Jean University of Alberta Edmonton AB Canada
| | - Paul Goede
- Laboratory of Endocrinology Amsterdam Gastroenterology & Metabolism Amsterdam University Medical Center University of Amsterdam Amsterdam The Netherlands
| | - Katie A. O'Brien
- Department of Physiology, Development and Neuroscience University of Cambridge Cambridge UK
| | - Belma Turan
- Laboratory of Endocrinology Amsterdam Gastroenterology & Metabolism Amsterdam University Medical Center University of Amsterdam Amsterdam The Netherlands
| | - Erkan Tuncay
- Department of Biophysics Faculty of Medicine Ankara University Ankara Turkey
| | - Yusuf Olgar
- Department of Biophysics Faculty of Medicine Ankara University Ankara Turkey
| | - Anabela P. Rolo
- Department of Life Sciences University of Coimbra and Center for Neurosciences and Cell Biology University of Coimbra Coimbra Portugal
| | - Carlos M. Palmeira
- Department of Life Sciences University of Coimbra and Center for Neurosciences and Cell Biology University of Coimbra Coimbra Portugal
| | - Neoma T. Boardman
- Cardiovascular Research Group Department of Medical Biology UiT the Arctic University of Norway Tromso Norway
| | - Rob C. I. Wüst
- Laboratory for Myology Department of Human Movement Sciences Faculty of Behavioural and Movement Sciences Amsterdam Movement Sciences Vrije Universiteit Amsterdam Amsterdam The Netherlands
| | - Terje S. Larsen
- Cardiovascular Research Group Department of Medical Biology UiT the Arctic University of Norway Tromso Norway
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15
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Schneider J, Han WH, Matthew R, Sauvé Y, Lemieux H. Age and sex as confounding factors in the relationship between cardiac mitochondrial function and type 2 diabetes in the Nile Grass rat. PLoS One 2020; 15:e0228710. [PMID: 32084168 PMCID: PMC7034865 DOI: 10.1371/journal.pone.0228710] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2019] [Accepted: 01/21/2020] [Indexed: 12/14/2022] Open
Abstract
Our study revisits the role of cardiac mitochondrial adjustments during the progression of type 2 diabetes mellitus (T2DM), while considering age and sex as potential confounding factors. We used the Nile Grass rats (NRs) as the animal model. After weaning, animals were fed either a Standard Rodent Chow Diet (SRCD group) or a Mazuri Chinchilla Diet (MCD group) consisting of high-fiber and low-fat content. Both males and females in the SRCD group, exhibited increased body mass, body mass index, and plasma insulin compared to the MCD group animals. However, the females were able to preserve their fasting blood glucose throughout the age range on both diets, while the males showed significant hyperglycemia starting at 6 months in the SRCD group. In the males, a higher citrate synthase activity-a marker of mitochondrial content-was measured at 2 months in the SRCD compared to the MCD group, and this was followed by a decline with age in the SRCD group only. In contrast, females preserved their mitochondrial content throughout the age range. In the males exclusively, the complex IV capacity expressed independently of mitochondrial content varied with age in a diet-specific pattern; the capacity was elevated at 2 months in the SRCD group, and at 6 months in the MCD group. In addition, females, but not males, were able to adjust their capacity to oxidize long-chain fatty acid in accordance with the fat content of the diet. Our results show clear sexual dimorphism in the variation of mitochondrial content and oxidative phosphorylation capacity with diet and age. The SRCD not only leads to T2DM but also exacerbates age-related cardiac mitochondrial defects. These observations, specific to male NRs, might reflect deleterious dietary-induced changes on their metabolism making them more prone to the cardiovascular consequences of aging and T2DM.
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Affiliation(s)
- Jillian Schneider
- Faculty Saint-Jean, University of Alberta, Edmonton, Alberta, Canada
- Department of Physiology, University of Alberta, Edmonton, Alberta, Canada
| | - Woo Hyun Han
- Faculty Saint-Jean, University of Alberta, Edmonton, Alberta, Canada
- Department of Ophthalmology and Visual Sciences, University of Alberta, Edmonton, Alberta, Canada
| | - Rebecca Matthew
- Faculty Saint-Jean, University of Alberta, Edmonton, Alberta, Canada
| | - Yves Sauvé
- Department of Physiology, University of Alberta, Edmonton, Alberta, Canada
- Department of Ophthalmology and Visual Sciences, University of Alberta, Edmonton, Alberta, Canada
| | - Hélène Lemieux
- Faculty Saint-Jean, University of Alberta, Edmonton, Alberta, Canada
- Department of Medicine, Women and Children's Health Research Institute, University of Alberta, Edmonton, Alberta, Canada
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16
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Close AF, Dadheech N, Lemieux H, Wang Q, Buteau J. Disruption of Beta-Cell Mitochondrial Networks by the Orphan Nuclear Receptor Nor1/Nr4a3. Cells 2020; 9:cells9010168. [PMID: 31936632 PMCID: PMC7017372 DOI: 10.3390/cells9010168] [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] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2019] [Revised: 01/03/2020] [Accepted: 01/04/2020] [Indexed: 12/14/2022] Open
Abstract
Nor1, the third member of the Nr4a subfamily of nuclear receptor, is garnering increased interest in view of its role in the regulation of glucose homeostasis. Our previous study highlighted a proapoptotic role of Nor1 in pancreatic beta cells and showed that Nor1 expression was increased in islets isolated from type 2 diabetic individuals, suggesting that Nor1 could mediate the deterioration of islet function in type 2 diabetes. However, the mechanism remains incompletely understood. We herein investigated the subcellular localization of Nor1 in INS832/13 cells and dispersed human beta cells. We also examined the consequences of Nor1 overexpression on mitochondrial function and morphology. Our results show that, surprisingly, Nor1 is mostly cytoplasmic in beta cells and undergoes mitochondrial translocation upon activation by proinflammatory cytokines. Mitochondrial localization of Nor1 reduced glucose oxidation, lowered ATP production rates, and inhibited glucose-stimulated insulin secretion. Western blot and microscopy images revealed that Nor1 could provoke mitochondrial fragmentation via mitophagy. Our study unveils a new mode of action for Nor1, which affects beta-cell viability and function by disrupting mitochondrial networks.
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Affiliation(s)
- Anne-Françoise Close
- Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, AB T6G 2E1, Canada
| | - Nidheesh Dadheech
- Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, AB T6G 2E1, Canada
| | - Hélène Lemieux
- Faculty Saint-Jean, Department of Medicine, University of Alberta, Edmonton, AB T6C 4G9, Canada
| | - Qian Wang
- Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, AB T6G 2E1, Canada
| | - Jean Buteau
- Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, AB T6G 2E1, Canada
- Correspondence: ; Tel.: +1-780-492-8386
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Scott KY, Matthew R, Woolcock J, Silva M, Lemieux H. Adjustments in the control of mitochondrial respiratory capacity to tolerate temperature fluctuations. ACTA ACUST UNITED AC 2019; 222:jeb.207951. [PMID: 31439652 DOI: 10.1242/jeb.207951] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2019] [Accepted: 08/14/2019] [Indexed: 12/19/2022]
Abstract
As the world's climate changes, life faces an evolving thermal environment. Mitochondrial oxidative phosphorylation (OXPHOS) is critical to ensure sufficient cellular energy production, and it is strongly influenced by temperature. The thermally induced changes to the regulation of specific steps within the OXPHOS process are poorly understood. In our study, we used the eurythermal species of planarian Dugesia tigrina to study the thermal sensitivity of the OXPHOS process at 10, 15, 20, 25 and 30°C. We conducted cold acclimation experiments where we measured the adjustment of specific steps in OXPHOS at two assay temperatures (10 and 20°C) following 4 weeks of acclimation under normal (22°C) or low (5°C) temperature conditions. At the low temperature, the contribution of the NADH pathway to the maximal OXPHOS capacity, in a combined pathway (NADH and succinate), was reduced. There was partial compensation by an increased contribution of the succinate pathway. As the temperature decreased, OXPHOS became more limited by the capacity of the phosphorylation system. Acclimation to the low temperature resulted in positive adjustments of the NADH pathway capacity due, at least in part, to an increase in complex I activity. The acclimation also resulted in a better match between OXPHOS and phosphorylation system capacities. Both of these adjustments following acclimation were specific to the low assay temperature. We conclude that there is substantial plasticity in the mitochondrial OXPHOS process following thermal acclimation in D. tigrina, and this probably contributes to the wide thermal range of the species.
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Affiliation(s)
- Katrina Y Scott
- Faculty Saint-Jean, University of Alberta, Edmonton, AB, Canada, T6C 4G9
| | - Rebecca Matthew
- Faculty Saint-Jean, University of Alberta, Edmonton, AB, Canada, T6C 4G9
| | - Jennifer Woolcock
- Faculty Saint-Jean, University of Alberta, Edmonton, AB, Canada, T6C 4G9
| | - Maise Silva
- Faculty Saint-Jean, University of Alberta, Edmonton, AB, Canada, T6C 4G9.,Faculdade de Tecnologia e Ciências, Salvador, Bahia, 41741-590, Brazil
| | - Hélène Lemieux
- Faculty Saint-Jean, University of Alberta, Edmonton, AB, Canada, T6C 4G9 .,Department of Medicine, Women and Children's Health Research Institute, University of Alberta, Edmonton, AB, Canada, T6G 2R7
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18
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Scavuzzo CJ, LeBlancq MJ, Nargang F, Lemieux H, Hamilton TJ, Dickson CT. The amnestic agent anisomycin disrupts intrinsic membrane properties of hippocampal neurons via a loss of cellular energetics. J Neurophysiol 2019; 122:1123-1135. [PMID: 31291154 PMCID: PMC6766744 DOI: 10.1152/jn.00370.2019] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2019] [Revised: 07/08/2019] [Accepted: 07/08/2019] [Indexed: 12/20/2022] Open
Abstract
The nearly axiomatic idea that de novo protein synthesis is necessary for long-term memory consolidation is based heavily on behavioral studies using translational inhibitors such as anisomycin. Although inhibiting protein synthesis has been shown to disrupt the expression of memory, translational inhibitors also have been found to profoundly disrupt basic neurobiological functions, including the suppression of ongoing neural activity in vivo. In the present study, using transverse hippocampal brain slices, we monitored the passive and active membrane properties of hippocampal CA1 pyramidal neurons using intracellular whole cell recordings during a brief ~30-min exposure to fast-bath-perfused anisomycin. Anisomycin suppressed protein synthesis to 46% of control levels as measured using incorporation of radiolabeled amino acids and autoradiography. During its application, anisomycin caused a significant depolarization of the membrane potential, without any changes in apparent input resistance or membrane time constant. Anisomycin-treated neurons also showed significant decreases in firing frequencies and spike amplitudes, and showed increases in spike width across spike trains, without changes in spike threshold. Because these changes indicated a loss of cellular energetics contributing to maintenance of ionic gradients across the membrane, we confirmed that anisomycin impaired mitochondrial function by reduced staining with 2,3,5-triphenyltetrazolium chloride and also impaired cytochrome c oxidase (complex IV) activity as indicated through high-resolution respirometry. These findings emphasize that anisomycin-induced alterations in neural activity and metabolism are a likely consequence of cell-wide translational inhibition. Critical reevaluation of studies using translational inhibitors to promote the protein synthesis dependent idea of long-term memory is absolutely necessary.NEW & NOTEWORTHY Memory consolidation is thought to be dependent on the synthesis of new proteins because translational inhibitors produce amnesia when administered just after learning. However, these agents also disrupt basic neurobiological functions. We show that blocking protein synthesis disrupts basic membrane properties of hippocampal neurons that correspond to induced disruptions of mitochondrial function. It is likely that translational inhibitors cause amnesia through their disruption of neural activity as a result of dysfunction of intracellular energetics.
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Affiliation(s)
- C. J. Scavuzzo
- Department of Psychology, University of Alberta, Edmonton, Alberta, Canada
| | - M. J. LeBlancq
- Neuroscience and Mental Health Institute, University of Alberta, Edmonton, Alberta, Canada
| | - F. Nargang
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada
| | - H. Lemieux
- Faculty Saint-Jean, Department of Medicine, Women and Children's Health Research Institute, University of Alberta, Edmonton, Alberta, Canada
| | - T. J. Hamilton
- Neuroscience and Mental Health Institute, University of Alberta, Edmonton, Alberta, Canada
- Department of Psychology, MacEwan University, Edmonton, Alberta, Canada
| | - C. T. Dickson
- Department of Psychology, University of Alberta, Edmonton, Alberta, Canada
- Neuroscience and Mental Health Institute, University of Alberta, Edmonton, Alberta, Canada
- Department of Physiology, University of Alberta, Edmonton, Alberta, Canada
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19
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Tosi I, Art T, Cassart D, Farnir F, Ceusters J, Serteyn D, Lemieux H, Votion DM. Altered mitochondrial oxidative phosphorylation capacity in horses suffering from polysaccharide storage myopathy. J Bioenerg Biomembr 2018; 50:379-390. [PMID: 30143916 DOI: 10.1007/s10863-018-9768-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [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: 03/08/2018] [Accepted: 08/15/2018] [Indexed: 12/22/2022]
Abstract
Polysaccharide storage myopathy (PSSM) is a widely described cause of exertional rhabdomyolysis in horses. Mitochondria play a central role in cellular energetics and are involved in human glycogen storage diseases but their role has been overlooked in equine PSSM. We hypothesized that the mitochondrial function is impaired in the myofibers of PSSM-affected horses. Nine horses with a history of recurrent exercise-associated rhabdomyolysis were tested for the glycogen synthase 1 gene (GYS1) mutation: 5 were tested positive (PSSM group) and 4 were tested negative (horses suffering from rhabdomyolysis of unknown origin, RUO group). Microbiopsies were collected from the gluteus medius (gm) and triceps brachii (tb) muscles of PSSM, RUO and healthy controls (HC) horses and used for histological analysis and for assessment of oxidative phosphorylation (OXPHOS) using high-resolution respirometry. The modification of mitochondrial respiration between HC, PSSM and RUO horses varied according to the muscle and to substrates feeding OXPHOS. In particular, compared to HC horses, the gm muscle of PSSM horses showed decreased OXPHOS- and electron transfer (ET)-capacities in presence of glutamate&malate&succinate. RUO horses showed a higher OXPHOS-capacity (with glutamate&malate) and ET-capacity (with glutamate&malate&succinate) in both muscles in comparison to the PSSM group. When expressed as ratios, our results highlighted a higher contribution of the NADH pathway (feeding electrons into Complex I) to maximal OXPHOS or ET-capacity in both rhabdomyolysis groups compared to the HC. Specific modifications in mitochondrial function might contribute to the pathogenesis of PSSM and of other types of exertional rhabdomyolyses.
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Affiliation(s)
- Irene Tosi
- Equine Sports Medicine Centre, Department of Functional Sciences, Fundamental and Applied Research for Animals & Health (FARAH), Faculty of Veterinary Medicine, University of Liège, Avenue de Cureghem, 7A (B42), Quartier Vallée 2, Sart Tilman, B-4000, Liège, Belgium.
| | - Tatiana Art
- Equine Sports Medicine Centre, Department of Functional Sciences, Fundamental and Applied Research for Animals & Health (FARAH), Faculty of Veterinary Medicine, University of Liège, Avenue de Cureghem, 7A (B42), Quartier Vallée 2, Sart Tilman, B-4000, Liège, Belgium
| | - Dominique Cassart
- Department of pathology, Fundamental and Applied Research for Animals & Health (FARAH), Faculty of Veterinary Medicine, University of Liège, Liège, Belgium
| | - Frédéric Farnir
- Department of animal productions: Biostatistics and Bioinformatics Applied in Veterinary Sciences, Fundamental and Applied Research for Animals & Health (FARAH), Faculty of Veterinary Medicine, University of Liège, Liège, Belgium
| | - Justine Ceusters
- Centre of Oxygen, Research and Development, University of Liège, Liège, Belgium
| | - Didier Serteyn
- Centre of Oxygen, Research and Development, University of Liège, Liège, Belgium.,Equine Pole, Fundamental and Applied Research for Animals & Health (FARAH), Faculty of Veterinary Medicine, Liège, Belgium
| | - Hélène Lemieux
- Faculty Saint-Jean, University of Alberta, Edmonton, AB, Canada
| | - Dominique-Marie Votion
- Equine Pole, Fundamental and Applied Research for Animals & Health (FARAH), Faculty of Veterinary Medicine, Liège, Belgium
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20
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Lou PH, Lucchinetti E, Scott KY, Huang Y, Gandhi M, Hersberger M, Clanachan AS, Lemieux H, Zaugg M. Alterations in fatty acid metabolism and sirtuin signaling characterize early type-2 diabetic hearts of fructose-fed rats. Physiol Rep 2018; 5:5/16/e13388. [PMID: 28830979 PMCID: PMC5582268 DOI: 10.14814/phy2.13388] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [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: 06/27/2017] [Accepted: 07/24/2017] [Indexed: 01/25/2023] Open
Abstract
Despite the fact that skeletal muscle insulin resistance is the hallmark of type‐2 diabetes mellitus (T2DM), inflexibility in substrate energy metabolism has been observed in other tissues such as liver, adipose tissue, and heart. In the heart, structural and functional changes ultimately lead to diabetic cardiomyopathy. However, little is known about the early biochemical changes that cause cardiac metabolic dysregulation and dysfunction. We used a dietary model of fructose‐induced T2DM (10% fructose in drinking water for 6 weeks) to study cardiac fatty acid metabolism in early T2DM and related signaling events in order to better understand mechanisms of disease. In early type‐2 diabetic hearts, flux through the fatty acid oxidation pathway was increased as a result of increased cellular uptake (CD36), mitochondrial uptake (CPT1B), as well as increased β‐hydroxyacyl‐CoA dehydrogenase and medium‐chain acyl‐CoA dehydrogenase activities, despite reduced mitochondrial mass. Long‐chain acyl‐CoA dehydrogenase activity was slightly decreased, resulting in the accumulation of long‐chain acylcarnitine species. Cardiac function and overall mitochondrial respiration were unaffected. However, evidence of oxidative stress and subtle changes in cardiolipin content and composition were found in early type‐2 diabetic mitochondria. Finally, we observed decreased activity of SIRT1, a pivotal regulator of fatty acid metabolism, despite increased protein levels. This indicates that the heart is no longer capable of further increasing its capacity for fatty acid oxidation. Along with increased oxidative stress, this may represent one of the earliest signs of dysfunction that will ultimately lead to inflammation and remodeling in the diabetic heart.
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Affiliation(s)
- Phing-How Lou
- Department of Pharmacology, University of Alberta, Edmonton, Alberta, Canada
| | - Eliana Lucchinetti
- Department of Anesthesiology and Pain Medicine, University of Alberta, Edmonton, Alberta, Canada
| | - Katrina Y Scott
- Department of Pharmacology, University of Alberta, Edmonton, Alberta, Canada
| | - Yiming Huang
- Department of Pharmacology, University of Alberta, Edmonton, Alberta, Canada
| | - Manoj Gandhi
- Department of Pharmacology, University of Alberta, Edmonton, Alberta, Canada
| | - Martin Hersberger
- Division of Clinical Chemistry and Biochemistry, University Children's Hospital Zürich, Zurich, Switzerland
| | | | - Hélène Lemieux
- Faculty Saint-Jean, University of Alberta, Edmonton, Alberta, Canada
| | - Michael Zaugg
- Department of Pharmacology, University of Alberta, Edmonton, Alberta, Canada .,Department of Anesthesiology and Pain Medicine, University of Alberta, Edmonton, Alberta, Canada
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21
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Dejos C, Kuny S, Han WH, Capel H, Lemieux H, Sauvé Y. Photoreceptor-induced RPE phagolysosomal maturation defects in Stargardt-like Maculopathy (STGD3). Sci Rep 2018; 8:5944. [PMID: 29654292 PMCID: PMC5899129 DOI: 10.1038/s41598-018-24357-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [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: 02/08/2018] [Accepted: 03/28/2018] [Indexed: 11/09/2022] Open
Abstract
For many neurodegenerative disorders, expression of a pathological protein by one cell type impedes function of other cell types, which in turn contributes to the death of the first cell type. In transgenic mice modelling Stargardt-like (STGD3) maculopathy, human mutant ELOVL4 expression by photoreceptors is associated with defects in the underlying retinal pigment epithelium (RPE). To examine how photoreceptors exert cytotoxic effects on RPE cells, transgenic ELOVL4 (TG1-2 line; TG) and wild-type (WT) littermates were studied one month prior (preclinical stage) to onset of photoreceptor loss (two months). TG photoreceptor outer segments presented to human RPE cells are recognized and internalized into phagosomes, but their digestion is delayed. Live RPE cell imaging pinpoints decreased numbers of acidified phagolysomes. In vivo, master regulator of lysosomal genes, transcription factor EB (TFEB), and key lysosomal enzyme Cathepsin D are both unaffected. Oxidative stress, as ruled out with high-resolution respirometry, does not play a role at such an early stage. Upregulation of CRYBA1/A3 and phagocytic cells (microglia/macrophages) interposed between RPE and photoreceptors support adaptive responses to processing delays. Impaired phagolysosomal maturation is observed in RPE of mice expressing human mutant ELOVL4 in their photoreceptors prior to photoreceptor death and associated vision loss.
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Affiliation(s)
- Camille Dejos
- Department of Ophthalmology and Visual Sciences, University of Alberta, 7-45 Medical Sciences Building, Edmonton, AB, T6G 2H7, Canada
| | - Sharee Kuny
- Department of Ophthalmology and Visual Sciences, University of Alberta, 7-45 Medical Sciences Building, Edmonton, AB, T6G 2H7, Canada
| | - Woo Hyun Han
- Department of Ophthalmology and Visual Sciences, University of Alberta, 7-45 Medical Sciences Building, Edmonton, AB, T6G 2H7, Canada
| | - Heather Capel
- Department of Physiology, University of Alberta, 7-45 Medical Sciences Building, Edmonton, AB, T6G 2H7, Canada
| | - Hélène Lemieux
- Faculty Saint-Jean, University of Alberta, 8406 Rue Marie-Anne Gaboury Northwest, Edmonton, AB, T6C 4G9, Canada
| | - Yves Sauvé
- Department of Ophthalmology and Visual Sciences, University of Alberta, 7-45 Medical Sciences Building, Edmonton, AB, T6G 2H7, Canada. .,Department of Physiology, University of Alberta, 7-45 Medical Sciences Building, Edmonton, AB, T6G 2H7, Canada.
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22
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Woodman AG, Mah R, Keddie D, Noble RMN, Panahi S, Gragasin FS, Lemieux H, Bourque SL. Prenatal iron deficiency causes sex-dependent mitochondrial dysfunction and oxidative stress in fetal rat kidneys and liver. FASEB J 2018; 32:3254-3263. [PMID: 29401611 DOI: 10.1096/fj.201701080r] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Prenatal iron deficiency alters fetal developmental trajectories, which results in persistent changes in organ function. Here, we studied the effects of prenatal iron deficiency on fetal kidney and liver mitochondrial function. Pregnant Sprague-Dawley rats were fed partially or fully iron-restricted diets to induce a state of moderate or severe iron deficiency alongside iron-replete control rats. We assessed mitochondrial function via high-resolution respirometry and reactive oxygen species generation via fluorescence microscopy on gestational d 21. Hemoglobin levels were reduced in dams in the moderate (-31%) and severe groups (-54%) compared with controls, which was accompanied by 55% reductions in fetal hemoglobin levels in both moderate and severe groups versus controls. Male iron-deficient kidneys exhibited globally reduced mitochondrial content and respiration, as well as increased cytosolic superoxide and decreased NO. Female iron-deficient kidneys exhibited complex II down-regulation and increased mitochondrial oxidative stress. Male iron-deficient livers exhibited reduced complex IV respiration and increased cytosolic superoxide, whereas female liver tissues exhibited no alteration in oxidant levels or mitochondrial function. These findings indicate that prenatal iron deficiency causes changes in mitochondrial content and function as well as oxidant status in a sex- and organ-dependent manner, which may be an important mechanism that underlies the programming of cardiovascular disease.-Woodman, A. G., Mah, R., Keddie, D., Noble, R. M. N., Panahi, S., Gragasin, F. S., Lemieux, H., Bourque, S. L. Prenatal iron deficiency causes sex-dependent mitochondrial dysfunction and oxidative stress in fetal rat kidneys and liver.
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Affiliation(s)
- Andrew G Woodman
- Department of Pharmacology, University of Alberta, Edmonton, Alberta, Canada.,Women and Children's Health Research Institute, University of Alberta, Edmonton, Alberta, Canada
| | - Richard Mah
- Women and Children's Health Research Institute, University of Alberta, Edmonton, Alberta, Canada.,Department of Anesthesiology and Pain Medicine, University of Alberta, Edmonton, Alberta, Canada
| | - Danae Keddie
- Women and Children's Health Research Institute, University of Alberta, Edmonton, Alberta, Canada.,Department of Anesthesiology and Pain Medicine, University of Alberta, Edmonton, Alberta, Canada
| | - Ronan M N Noble
- Women and Children's Health Research Institute, University of Alberta, Edmonton, Alberta, Canada.,Department of Anesthesiology and Pain Medicine, University of Alberta, Edmonton, Alberta, Canada
| | - Sareh Panahi
- Women and Children's Health Research Institute, University of Alberta, Edmonton, Alberta, Canada.,Department of Anesthesiology and Pain Medicine, University of Alberta, Edmonton, Alberta, Canada
| | - Ferrante S Gragasin
- Women and Children's Health Research Institute, University of Alberta, Edmonton, Alberta, Canada.,Department of Anesthesiology and Pain Medicine, University of Alberta, Edmonton, Alberta, Canada
| | - Hélène Lemieux
- Faculty Saint-Jean, University of Alberta, Edmonton, Alberta, Canada
| | - Stephane L Bourque
- Department of Pharmacology, University of Alberta, Edmonton, Alberta, Canada.,Women and Children's Health Research Institute, University of Alberta, Edmonton, Alberta, Canada.,Department of Anesthesiology and Pain Medicine, University of Alberta, Edmonton, Alberta, Canada
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23
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Kake-Guena S, Touisse K, Warren B, Scott K, Dufresne F, Blier P, Lemieux H. Temperature-related differences in mitochondrial function among clones of the cladoceran Daphnia pulex. J Therm Biol 2017; 69:23-31. [DOI: 10.1016/j.jtherbio.2017.05.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2017] [Revised: 05/10/2017] [Accepted: 05/20/2017] [Indexed: 10/19/2022]
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Han WH, Gotzmann J, Kuny S, Huang H, Chan CB, Lemieux H, Sauvé Y. Modifications in Retinal Mitochondrial Respiration Precede Type 2 Diabetes and Protracted Microvascular Retinopathy. Invest Ophthalmol Vis Sci 2017; 58:3826-3839. [PMID: 28763556 DOI: 10.1167/iovs.17-21929] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [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] Open
Abstract
Purpose To characterize retinal mitochondrial respiration associated with type 2 diabetes (T2D) progression in a cone-rich diurnal rodent, the Nile rat (genus Arvicanthis, species niloticus). Methods Nile rats were fed a standard rodent diet that resulted in rising glucose levels from 6 months. Age-matched control animals were fed a high-fiber diet that prevented diabetes up to 18 months. The functional status of specific retinal mitochondrial components and mitochondrial outer membrane integrity were studied by using high-resolution respirometry. Ocular complications were documented with funduscopy, electroretinography (ERG), and trypsin digestion of retinal vasculature. Results Mitochondrial functional changes were detected during hyperinsulinemia with maintained normoglycemia (2 months), corresponding to stage 1 of human T2D. Our data showed increased contribution of mitochondrial respiration through the NADH pathway relative to maximal oxidative phosphorylation capacity, with simultaneous electron entry into NADH (Complex I and related dehydrogenases) and succinate (Complex II) pathways. These compensatory events coincided with compromised mitochondrial outer membrane integrity. The first clinical sign of retinopathy (pericyte loss) was only detected at 12 months (after 6 months of sustained hyperglycemia) alongside a common ocular complication of diabetes, cataractogenesis. Further prolongation of hyperglycemia (from 12 to 18 months) led to capillary degeneration and delayed photopic ERG oscillatory potentials. Conclusions Oxidative phosphorylation compensatory changes in the retina can be detected as early as 2 months, before development of hyperglycemia, and are associated with reduced mitochondrial outer membrane integrity.
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Affiliation(s)
- Woo Hyun Han
- Department of Ophthalmology and Visual Sciences, University of Alberta, Edmonton, Alberta, Canada
| | - Jonathan Gotzmann
- Department of Physiology, University of Alberta, Edmonton, Alberta, Canada
| | - Sharee Kuny
- Department of Ophthalmology and Visual Sciences, University of Alberta, Edmonton, Alberta, Canada
| | - Hui Huang
- Department of Physiology, University of Alberta, Edmonton, Alberta, Canada
| | - Catherine B Chan
- Department of Physiology, University of Alberta, Edmonton, Alberta, Canada 3Agriculture, Food and Nutritional Science, University of Alberta, Edmonton, Alberta, Canada
| | - Hélène Lemieux
- Faculty Saint-Jean, University of Alberta, Edmonton, Alberta, Canada
| | - Yves Sauvé
- Department of Ophthalmology and Visual Sciences, University of Alberta, Edmonton, Alberta, Canada 2Department of Physiology, University of Alberta, Edmonton, Alberta, Canada
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25
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Lemieux H, Boemer F, van Galen G, Serteyn D, Amory H, Baise E, Cassart D, van Loon G, Marcillaud-Pitel C, Votion DM. Mitochondrial function is altered in horse atypical myopathy. Mitochondrion 2016; 30:35-41. [PMID: 27374763 DOI: 10.1016/j.mito.2016.06.005] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [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: 03/10/2016] [Revised: 05/30/2016] [Accepted: 06/28/2016] [Indexed: 12/31/2022]
Abstract
Equine atypical myopathy in Europe is a fatal rhabdomyolysis syndrome that results from the ingestion of hypoglycin A contained in seeds and seedlings of Acer pseudoplatanus (sycamore maple). Acylcarnitine concentrations in serum and muscle OXPHOS capacity were determined in 15 atypical myopathy cases. All but one acylcarnitine were out of reference range and mitochondrial respiratory capacity was severely decreased up to 49% as compared to 10 healthy controls. The hallmark of atypical myopathy thus consists of a severe alteration in the energy metabolism including a severe impairment in muscle mitochondrial respiration that could contribute to its high death rate.
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Affiliation(s)
- Hélène Lemieux
- Faculty Saint-Jean, University of Alberta, Edmonton, Alberta, Canada
| | - François Boemer
- Biochemical Genetics Laboratory, Human Genetics, CHU Liege, University of Liege, Belgium
| | - Gaby van Galen
- (c)Equine Clinic, Fundamental and Applied Research for Animals & Health (FARAH), Faculty of Veterinary Medicine, University of Liege, Belgium
| | - Didier Serteyn
- (c)Equine Clinic, Fundamental and Applied Research for Animals & Health (FARAH), Faculty of Veterinary Medicine, University of Liege, Belgium; Centre of Oxygen, Research and Development, University of Liege, Liege, Belgium
| | - Hélène Amory
- (c)Equine Clinic, Fundamental and Applied Research for Animals & Health (FARAH), Faculty of Veterinary Medicine, University of Liege, Belgium
| | - Etienne Baise
- (e)Department of Animal Productions: Biostatistics, Economy and Animal Selection, Fundamental and Applied Research for Animals & Health (FARAH), Faculty of Veterinary Medicine, University of Liege, Belgium
| | - Dominique Cassart
- Department of Pathology, Fundamental and Applied Research for Animals & Health (FARAH), Faculty of Veterinary Medicine, University of Liege, Belgium
| | | | | | - Dominique-M Votion
- (i)Equine Pole, Fundamental and Applied Research for Animals and Health (FARAH), Faculty of Veterinary Medicine, University of Liege, Belgium.
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26
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Kake-Guena SA, Touisse K, Vergilino R, Dufresne F, Blier PU, Lemieux H. Assessment of mitochondrial functions inDaphnia pulexclones using high-resolution respirometry. ACTA ACUST UNITED AC 2015; 323:292-300. [DOI: 10.1002/jez.1913] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2014] [Revised: 12/12/2014] [Accepted: 12/15/2014] [Indexed: 12/25/2022]
Affiliation(s)
| | - Kamal Touisse
- Campus Saint-Jean; University of Alberta; Edmonton Alberta Canada
| | - Roland Vergilino
- Département de biologie; Laboratoire de Physiologie Animale Intégrative; Université du Québec à Rimouski; Rimouski Québec Canada
| | - France Dufresne
- Département de biologie; Laboratoire de Physiologie Animale Intégrative; Université du Québec à Rimouski; Rimouski Québec Canada
| | - Pierre U. Blier
- Département de biologie; Laboratoire de Physiologie Animale Intégrative; Université du Québec à Rimouski; Rimouski Québec Canada
| | - Hélène Lemieux
- Campus Saint-Jean; University of Alberta; Edmonton Alberta Canada
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27
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Lou PH, Lucchinetti E, Zhang L, Affolter A, Gandhi M, Hersberger M, Warren BE, Lemieux H, Sobhi HF, Clanachan AS, Zaugg M. Loss of Intralipid®- but not sevoflurane-mediated cardioprotection in early type-2 diabetic hearts of fructose-fed rats: importance of ROS signaling. PLoS One 2014; 9:e104971. [PMID: 25127027 PMCID: PMC4134246 DOI: 10.1371/journal.pone.0104971] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2014] [Accepted: 07/15/2014] [Indexed: 12/28/2022] Open
Abstract
BACKGROUND Insulin resistance and early type-2 diabetes are highly prevalent. However, it is unknown whether Intralipid® and sevoflurane protect the early diabetic heart against ischemia-reperfusion injury. METHODS Early type-2 diabetic hearts from Sprague-Dawley rats fed for 6 weeks with fructose were exposed to 15 min of ischemia and 30 min of reperfusion. Intralipid® (1%) was administered at the onset of reperfusion. Peri-ischemic sevoflurane (2 vol.-%) served as alternative protection strategy. Recovery of left ventricular function was recorded and the activation of Akt and ERK 1/2 was monitored. Mitochondrial function was assessed by high-resolution respirometry and mitochondrial ROS production was measured by Amplex Red and aconitase activity assays. Acylcarnitine tissue content was measured and concentration-response curves of complex IV inhibition by palmitoylcarnitine were obtained. RESULTS Intralipid® did not exert protection in early diabetic hearts, while sevoflurane improved functional recovery. Sevoflurane protection was abolished by concomitant administration of the ROS scavenger N-2-mercaptopropionyl glycine. Sevoflurane, but not Intralipid® produced protective ROS during reperfusion, which activated Akt. Intralipid® failed to inhibit respiratory complex IV, while sevoflurane inhibited complex I. Early diabetic hearts exhibited reduced carnitine-palmitoyl-transferase-1 activity, but palmitoylcarnitine could not rescue protection and enhance postischemic functional recovery. Cardiac mitochondria from early diabetic rats exhibited an increased content of subunit IV-2 of respiratory complex IV and of uncoupling protein-3. CONCLUSIONS Early type-2 diabetic hearts lose complex IV-mediated protection by Intralipid® potentially due to a switch in complex IV subunit expression and increased mitochondrial uncoupling, but are amenable to complex I-mediated sevoflurane protection.
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Affiliation(s)
- Phing-How Lou
- Cardiovascular Research Centre, University of Alberta, Edmonton, Alberta, Canada
| | - Eliana Lucchinetti
- Department of Anesthesiology & Pain Medicine, University of Alberta, Edmonton, Alberta, Canada
| | - Liyan Zhang
- Department of Anesthesiology & Pain Medicine, University of Alberta, Edmonton, Alberta, Canada
| | - Andreas Affolter
- Department of Clinical Chemistry, University Children's Hospital Zurich, Zurich, Switzerland
| | - Manoj Gandhi
- Department of Pharmacology, University of Alberta, Edmonton, Alberta, Canada
| | - Martin Hersberger
- Department of Clinical Chemistry, University Children's Hospital Zurich, Zurich, Switzerland
| | - Blair E. Warren
- Campus Saint-Jean, University of Alberta, Edmonton, Alberta, Canada
| | - Hélène Lemieux
- Campus Saint-Jean, University of Alberta, Edmonton, Alberta, Canada
| | - Hany F. Sobhi
- Coppin Center for Organic Synthesis, Coppin State University, Baltimore, Maryland, United States of America
| | | | - Michael Zaugg
- Department of Anesthesiology & Pain Medicine, University of Alberta, Edmonton, Alberta, Canada
- * E-mail:
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Abstract
Changes in environmental temperature can pose considerable challenges to animals and shifts in thermal habitat have been shown to be a major force driving species’ adaptation. These adaptations have been the focus of major research efforts to determine the physiological or metabolic constraints related to temperature and to reveal the phenotypic characters that can or should adjust. Considering the current consensus on climate change, the focus of research will likely shift to questioning whether ectothermic organisms will be able to survive future modifications of their thermal niches. Organisms can adjust to temperature changes through physiological plasticity (e.g., acclimation), genetic adaptation, or via dispersal to more suitable thermal habitats. Thus, it is important to understand what genetic and phenotypic attributes—at the individual, population, and species levels—could improve survival success. These issues are particularly important for ectotherms, which are in thermal equilibrium with the surrounding environment. To start addressing these queries, we should consider what physiological or metabolic functions are responsible for the impact of temperature on organisms. Some recent developments indicate that mitochondria are key metabolic structures determining the thermal range that an organism can tolerate. The catalytic capacity of mitochondria is highly sensitive to thermal variation and therefore should partly dictate the temperature dependence of biological functions. Mitochondria contain a complex network of different enzymatic reaction pathways that interact synergistically. The precise regulation of both adenosine triphosphate (ATP) and reactive oxygen species (ROS) production depends on the integration of different enzymes and pathways. Here, we examine the temperature dependence of different parts of mitochondrial pathways and evaluate the evolutionary challenges that need to be overcome to ensure mitochondrial adaptations to new thermal environments.
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Affiliation(s)
- Pierre U. Blier
- Laboratoire de physiologie animale intégrative, Département de Biologie, Université du Québec, 300 Allée des Ursulines, Rimouski, QC G5L 3A1, Canada
| | - Hélène Lemieux
- Campus Saint-Jean, University of Alberta, 8406, Marie-Anne-Gaboury Street (91 Street), Edmonton, AB T6C 4G9, Canada
| | - Nicolas Pichaud
- Laboratoire de physiologie animale intégrative, Département de Biologie, Université du Québec, 300 Allée des Ursulines, Rimouski, QC G5L 3A1, Canada
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Warren BE, Lou PH, Lucchinetti E, Zhang L, Clanachan AS, Affolter A, Hersberger M, Zaugg M, Lemieux H. Early mitochondrial dysfunction in glycolytic muscle, but not oxidative muscle, of the fructose-fed insulin-resistant rat. Am J Physiol Endocrinol Metab 2014; 306:E658-67. [PMID: 24425766 PMCID: PMC3948982 DOI: 10.1152/ajpendo.00511.2013] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [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] [Indexed: 01/17/2023]
Abstract
Although evidence that type 2 diabetes mellitus (T2DM) is accompanied by mitochondrial dysfunction in skeletal muscle has been accumulating, a causal link between mitochondrial dysfunction and the pathogenesis of the disease remains unclear. Our study focuses on an early stage of the disease to determine whether mitochondrial dysfunction contributes to the development of T2DM. The fructose-fed (FF) rat was used as an animal model of early T2DM. Mitochondrial respiration and acylcarnitine species were measured in oxidative (soleus) and glycolytic [extensor digitorum longus (EDL)] muscle. Although FF rats displayed characteristic signs of T2DM, including hyperglycemia, hyperinsulinemia, and hypertriglyceridemia, mitochondrial content was preserved in both muscles from FF rats. The EDL muscle had reduced complex I and complex I and II respiration in the presence of pyruvate but not glutamate. The decrease in pyruvate-supported respiration was due to a decrease in pyruvate dehydrogenase activity. Accumulation of C14:1 and C14:2 acylcarnitine species and a decrease in respiration supported by long-chain acylcarnitines but not acetylcarnitine indicated dysfunctional β-oxidation in the EDL muscle. In contrast, the soleus muscle showed preserved mitochondrial respiration, pyruvate dehydrogenase activity, and increased fatty acid oxidation, as evidenced by overall reduced acylcarnitine levels. Aconitase activity, a sensitive index of reactive oxygen species production in mitochondria, was reduced exclusively in EDL muscle, which showed lower levels of the antioxidant enzymes thioredoxin reductase and glutathione peroxidase. Here, we show that the glycolytic EDL muscle is more prone to an imbalance between energy supply and oxidation caused by insulin resistance than the oxidative soleus muscle.
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Affiliation(s)
- Blair E Warren
- Campus Saint-Jean, University of Alberta, Edmonton, Alberta, Canada
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Lou PH, Lucchinetti E, Zhang L, Affolter A, Schaub MC, Gandhi M, Hersberger M, Warren BE, Lemieux H, Sobhi HF, Clanachan AS, Zaugg M. The mechanism of Intralipid®-mediated cardioprotection complex IV inhibition by the active metabolite, palmitoylcarnitine, generates reactive oxygen species and activates reperfusion injury salvage kinases. PLoS One 2014; 9:e87205. [PMID: 24498043 PMCID: PMC3907505 DOI: 10.1371/journal.pone.0087205] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2013] [Accepted: 12/23/2013] [Indexed: 12/16/2022] Open
Abstract
BACKGROUND Intralipid® administration at reperfusion elicits protection against myocardial ischemia-reperfusion injury. However, the underlying mechanisms are not fully understood. METHODS Sprague-Dawley rat hearts were exposed to 15 min of ischemia and 30 min of reperfusion in the absence or presence of Intralipid® 1% administered at the onset of reperfusion. In separate experiments, the reactive oxygen species (ROS) scavenger N-(2-mercaptopropionyl)-glycine was added either alone or with Intralipid®. Left ventricular work and activation of Akt, STAT3, and ERK1/2 were used to evaluate cardioprotection. ROS production was assessed by measuring the loss of aconitase activity and the release of hydrogen peroxide using Amplex Red. Electron transport chain complex activities and proton leak were measured by high-resolution respirometry in permeabilized cardiac fibers. Titration experiments using the fatty acid intermediates of Intralipid® palmitoyl-, oleoyl- and linoleoylcarnitine served to determine concentration-dependent inhibition of complex IV activity and mitochondrial ROS release. RESULTS Intralipid® enhanced postischemic recovery and activated Akt and Erk1/2, effects that were abolished by the ROS scavenger N-(2-mercaptopropionyl)glycine. Palmitoylcarnitine and linoleoylcarnitine, but not oleoylcarnitine concentration-dependently inhibited complex IV. Only palmitoylcarnitine reached high tissue concentrations during early reperfusion and generated significant ROS by complex IV inhibition. Palmitoylcarnitine (1 µM), administered at reperfusion, also fully mimicked Intralipid®-mediated protection in an N-(2-mercaptopropionyl)-glycine -dependent manner. CONCLUSIONS Our data describe a new mechanism of postconditioning cardioprotection by the clinically available fat emulsion, Intralipid®. Protection is elicited by the fatty acid intermediate palmitoylcarnitine, and involves inhibition of complex IV, an increase in ROS production and activation of the RISK pathway.
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Affiliation(s)
- Phing-How Lou
- Postdoctoral Fellow, Cardiovascular Research Centre, University of Alberta, Edmonton, AB, Canada
| | - Eliana Lucchinetti
- Research Associate, Department of Anesthesiology & Pain Medicine, University of Alberta, Edmonton, AB, Canada
| | - Liyan Zhang
- Research Associate, Department of Anesthesiology & Pain Medicine, University of Alberta, Edmonton, AB, Canada
| | - Andreas Affolter
- Research Associate, Department of Clinical Chemistry, University Children’s Hospital Zurich, Zurich, Switzerland
| | - Marcus C. Schaub
- Professor, Institute of Pharmacology and Toxicology, University of Zurich, Zurich, Switzerland
| | - Manoj Gandhi
- Research Associate, Department of Pharmacology, University of Alberta, Edmonton, AB, Canada
| | - Martin Hersberger
- Head of the Department of Clinical Chemistry, University Children’s Hospital Zurich, Zurich, Switzerland
| | - Blair E. Warren
- Undergraduate student, Campus Saint-Jean, University of Alberta, Edmonton, AB, Canada
| | - Hélène Lemieux
- Assistant Professor, Campus Saint-Jean, University of Alberta, Edmonton, AB, Canada
| | - Hany F. Sobhi
- Assistant Professor and Director of Coppin Center for Organic Synthesis, Coppin State University, Baltimore, Maryland, United States of America
| | | | - Michael Zaugg
- Professor, Department of Anesthesiology & Pain Medicine, University of Alberta, Edmonton, AB, Canada
- * E-mail:
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Lemieux H, Warren BE. An animal model to study human muscular diseases involving mitochondrial oxidative phosphorylation. J Bioenerg Biomembr 2012; 44:503-12. [DOI: 10.1007/s10863-012-9451-2] [Citation(s) in RCA: 10] [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] [Received: 05/10/2012] [Accepted: 05/30/2012] [Indexed: 12/25/2022]
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Votion DM, Gnaiger E, Lemieux H, Mouithys-Mickalad A, Serteyn D. Physical fitness and mitochondrial respiratory capacity in horse skeletal muscle. PLoS One 2012; 7:e34890. [PMID: 22529950 PMCID: PMC3329552 DOI: 10.1371/journal.pone.0034890] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2011] [Accepted: 03/08/2012] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND Within the animal kingdom, horses are among the most powerful aerobic athletic mammals. Determination of muscle respiratory capacity and control improves our knowledge of mitochondrial physiology in horses and high aerobic performance in general. METHODOLOGY/PRINCIPAL FINDINGS We applied high-resolution respirometry and multiple substrate-uncoupler-inhibitor titration protocols to study mitochondrial physiology in small (1.0-2.5 mg) permeabilized muscle fibres sampled from triceps brachii of healthy horses. Oxidative phosphorylation (OXPHOS) capacity (pmol O(2) • s(-1) • mg(-1) wet weight) with combined Complex I and II (CI+II) substrate supply (malate+glutamate+succinate) increased from 77 ± 18 in overweight horses to 103 ± 18, 122 ± 15, and 129 ± 12 in untrained, trained and competitive horses (N = 3, 8, 16, and 5, respectively). Similar to human muscle mitochondria, equine OXPHOS capacity was limited by the phosphorylation system to 0.85 ± 0.10 (N = 32) of electron transfer capacity, independent of fitness level. In 15 trained horses, OXPHOS capacity increased from 119 ± 12 to 134 ± 37 when pyruvate was included in the CI+II substrate cocktail. Relative to this maximum OXPHOS capacity, Complex I (CI)-linked OXPHOS capacities were only 50% with glutamate+malate, 64% with pyruvate+malate, and 68% with pyruvate+malate+glutamate, and ~78% with CII-linked succinate+rotenone. OXPHOS capacity with glutamate+malate increased with fitness relative to CI+II-supported ETS capacity from a flux control ratio of 0.38 to 0.40, 0.41 and 0.46 in overweight to competitive horses, whereas the CII/CI+II substrate control ratio remained constant at 0.70. Therefore, the apparent deficit of the CI- over CII-linked pathway capacity was reduced with physical fitness. CONCLUSIONS/SIGNIFICANCE The scope of mitochondrial density-dependent OXPHOS capacity and the density-independent (qualitative) increase of CI-linked respiratory capacity with increased fitness open up new perspectives of integrative and comparative mitochondrial respiratory physiology.
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Ye F, Lemieux H, Hoppel CL, Hanson RW, Hakimi P, Croniger CM, Puchowicz M, Anderson VE, Fujioka H, Stavnezer E. Peroxisome proliferator-activated receptor γ (PPARγ) mediates a Ski oncogene-induced shift from glycolysis to oxidative energy metabolism. J Biol Chem 2011; 286:40013-24. [PMID: 21917928 DOI: 10.1074/jbc.m111.292029] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Overexpression of the Ski oncogene induces oncogenic transformation of chicken embryo fibroblasts (CEFs). However, unlike most other oncogene-transformed cells, Ski-transformed CEFs (Ski-CEFs) do not display the classical Warburg effect. On the contrary, Ski transformation reduced lactate production and glucose utilization in CEFs. Compared with CEFs, Ski-CEFs exhibited enhanced TCA cycle activity, fatty acid catabolism through β-oxidation, glutamate oxidation, oxygen consumption, as well as increased numbers and mass of mitochondria. Interestingly, expression of PPARγ, a key transcription factor that regulates adipogenesis and lipid metabolism, was dramatically elevated at both the mRNA and protein levels in Ski-CEFs. Accordingly, PPARγ target genes that are involved in lipid uptake, transport, and oxidation were also markedly up-regulated by Ski. Knocking down PPARγ in Ski-CEFs by RNA interference reversed the elevated expression of these PPARγ target genes, as well as the shift to oxidative metabolism and the increased mitochondrial biogenesis. Moreover, we found that Ski co-immunoprecipitates with PPARγ and co-activates PPARγ-driven transcription.
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Affiliation(s)
- Fang Ye
- Department of Biochemistry, Case Western Reserve University School of Medicine, Cleveland, Ohio 44106, USA
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Lemieux H, Semsroth S, Antretter H, Höfer D, Gnaiger E. Mitochondrial respiratory control and early defects of oxidative phosphorylation in the failing human heart. Int J Biochem Cell Biol 2011; 43:1729-38. [PMID: 21871578 DOI: 10.1016/j.biocel.2011.08.008] [Citation(s) in RCA: 137] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2011] [Revised: 07/27/2011] [Accepted: 08/09/2011] [Indexed: 12/25/2022]
Abstract
Heart failure is a consequence of progressive deterioration of cardiac performance. Little is known about the role of impaired oxidative phosphorylation in the progression of the disease, since previous studies of mitochondrial injuries are restricted to end-stage chronic heart failure. The present study aimed at evaluating the involvement of mitochondrial dysfunction in the development of human heart failure. We measured the control of oxidative phosphorylation with high-resolution respirometry in permeabilized myocardial fibres from donor hearts (controls), and patients with no or mild heart failure but presenting with heart disease, or chronic heart failure due to dilated or ischemic cardiomyopathy. The capacity of the phosphorylation system exerted a strong limitation on oxidative phosphorylation in the human heart, estimated at 121 pmol O(2)s(-1)mg(-1) in the healthy left ventricle. In heart disease, a specific defect of the phosphorylation system, Complex I-linked respiration, and mass-specific fatty acid oxidation were identified. These early defects were also significant in chronic heart failure, where the capacities of the oxidative phosphorylation and electron transfer systems per cardiac tissue mass were decreased with all tested substrate combinations, suggesting a decline of mitochondrial density. Oxidative phosphorylation and electron transfer system capacities were higher in ventricles compared to atria, but the impaired mitochondrial quality was identical in the four cardiac chambers of chronic heart failure patients. Coupling was preserved in heart disease and chronic heart failure, in contrast to the mitochondrial dysfunction observed after prolonged cold storage of cardiac tissue. Mitochondrial defects in the phosphorylation system, Complex I respiration and mass-specific fatty acid oxidation occurred early in the development of heart failure. Targeting these mitochondrial injuries with metabolic therapy may offer a promising approach to delay the progression of heart disease.
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Affiliation(s)
- Hélène Lemieux
- D. Swarovski Research Laboratory, Department of Visceral, Transplant and Thoracic Surgery, Medical University of Innsbruck, A-6020 Innsbruck, Austria
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Lemieux H, Vazquez EJ, Fujioka H, Hoppel CL. Decrease in mitochondrial function in rat cardiac permeabilized fibers correlates with the aging phenotype. J Gerontol A Biol Sci Med Sci 2010; 65:1157-64. [PMID: 20801909 DOI: 10.1093/gerona/glq141] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
We measured the loss of cardiac mitochondrial function related to aging in males of three rat strains presenting with different longevity and aging phenotypes: the Fischer 344 (F344), the Brown Norway (BN), and the hybrid F344×BN. The F344 rat has a short life span and a ∼45% decrease in coupled mitochondrial oxidation in the cardiac permeabilized fibers from the old rats compared with the young rats. Citrate synthase activity in the permeabilized fibers (mitochondrial content) did not change significantly with aging. The BN live longer compared with the F344 and have a 15%-18% loss of mitochondrial respiration in the aged rats compared with the young rats. The differences are not significant. In hybrids, more resistant to aging than are the BN and the F344, mitochondrial function is preserved during aging. The difference in longevity of the different strains is correlated with mitochondrial dysfunction in the heart, suggesting the importance of mitochondria in cardiac aging.
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Affiliation(s)
- Hélène Lemieux
- Center for Mitochondrial Disease, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, OH 44106, USA
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Lemieux H, Rosca MG, Vazquez EJ, Kehres D, Gnaiger E, Hoppel CL. 133 Detection of mitochondrial defects in patients with mitochondrial diseases: A case study. Mitochondrion 2010. [DOI: 10.1016/j.mito.2009.12.124] [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: 11/27/2022]
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Lemieux H, Rosca MG, Vazquez EJ, Gnaiger E, Hoppel CL. 134 Permeabilized fibers or isolated mitochondria for the detection of oxidative phosphorylation defects in patients with mitochondrial diseases. Mitochondrion 2010. [DOI: 10.1016/j.mito.2009.12.125] [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: 11/15/2022]
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Lemieux H, Tardif JC, Blier PU. Thermal sensitivity of oxidative phosphorylation in rat heart mitochondria: Does pyruvate dehydrogenase dictate the response to temperature? J Therm Biol 2010; 35:105-111. [DOI: 10.1016/j.jtherbio.2009.12.003] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2009] [Revised: 11/24/2009] [Accepted: 12/08/2009] [Indexed: 10/20/2022]
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Abstract
Endogenous acetylcarnitine is an indicator of acetyl-CoA synthesized by multiple metabolic pathways involving carbohydrates, amino acids, fatty acids, sterols, and ketone bodies, and utilized mainly by the tricarboxylic acid cycle. Acetylcarnitine supplementation has beneficial effects in elderly animals and humans, including restoration of mitochondrial content and function. These effects appear to be dose-dependent and occur even after short-term therapy. In order to set the stage for understanding the mechanism of action of acetylcarnitine, we review the metabolism and role of this compound. We suggest that acetylation of mitochondrial proteins leads to a specific increase in mitochondrial gene expression and mitochondrial protein synthesis. In the aged rat heart, this effect is translated to increased cytochrome b content, restoration of complex III activity, and oxidative phosphorylation, resulting in amelioration of the age-related mitochondrial defect.
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Affiliation(s)
- Mariana G Rosca
- Center for Mitochondrial Diseases and Departments of Medicine and Pharmacology, Case Western Reserve University, Cleveland, Ohio
| | - Hélène Lemieux
- Center for Mitochondrial Diseases and Departments of Medicine and Pharmacology, Case Western Reserve University, Cleveland, Ohio
| | - Charles L Hoppel
- Center for Mitochondrial Diseases and Departments of Medicine and Pharmacology, Case Western Reserve University, Cleveland, Ohio
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Lemieux H, Troppmair J, Gnaiger E. 62. Early impairment of mitochondrial function in apoptosis and protection by overexpression of the antiapoptotic factor v-Raf in a mouse pro-myeloid cell line. Mitochondrion 2009. [DOI: 10.1016/j.mito.2008.12.056] [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: 11/29/2022]
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Lemieux H, Fraisl P, Aragones J, Geyte KV, Schneider M, Carmeliet P, Gnaiger E. 61. Functional consequences of genotypic differences studied by high-resolution respirometry in small samples of permeabilized skeletal muscle fibers. Mitochondrion 2009. [DOI: 10.1016/j.mito.2008.12.055] [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: 10/21/2022]
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Lemieux H, Semsroth S, Gnaiger E. S12.21 Respiratory control and mitochondrial defects in the failing human heart. Biochimica et Biophysica Acta (BBA) - Bioenergetics 2008. [DOI: 10.1016/j.bbabio.2008.05.316] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Aragonés J, Schneider M, Van Geyte K, Fraisl P, Dresselaers T, Mazzone M, Dirkx R, Zacchigna S, Lemieux H, Jeoung NH, Lambrechts D, Bishop T, Lafuste P, Diez-Juan A, Harten SK, Van Noten P, De Bock K, Willam C, Tjwa M, Grosfeld A, Navet R, Moons L, Vandendriessche T, Deroose C, Wijeyekoon B, Nuyts J, Jordan B, Silasi-Mansat R, Lupu F, Dewerchin M, Pugh C, Salmon P, Mortelmans L, Gallez B, Gorus F, Buyse J, Sluse F, Harris RA, Gnaiger E, Hespel P, Van Hecke P, Schuit F, Van Veldhoven P, Ratcliffe P, Baes M, Maxwell P, Carmeliet P. Deficiency or inhibition of oxygen sensor Phd1 induces hypoxia tolerance by reprogramming basal metabolism. Nat Genet 2008; 40:170-80. [PMID: 18176562 DOI: 10.1038/ng.2007.62] [Citation(s) in RCA: 370] [Impact Index Per Article: 23.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2007] [Accepted: 10/23/2007] [Indexed: 12/30/2022]
Abstract
HIF prolyl hydroxylases (PHD1-3) are oxygen sensors that regulate the stability of the hypoxia-inducible factors (HIFs) in an oxygen-dependent manner. Here, we show that loss of Phd1 lowers oxygen consumption in skeletal muscle by reprogramming glucose metabolism from oxidative to more anaerobic ATP production through activation of a Pparalpha pathway. This metabolic adaptation to oxygen conservation impairs oxidative muscle performance in healthy conditions, but it provides acute protection of myofibers against lethal ischemia. Hypoxia tolerance is not due to HIF-dependent angiogenesis, erythropoiesis or vasodilation, but rather to reduced generation of oxidative stress, which allows Phd1-deficient myofibers to preserve mitochondrial respiration. Hypoxia tolerance relies primarily on Hif-2alpha and was not observed in heterozygous Phd2-deficient or homozygous Phd3-deficient mice. Of medical importance, conditional knockdown of Phd1 also rapidly induces hypoxia tolerance. These findings delineate a new role of Phd1 in hypoxia tolerance and offer new treatment perspectives for disorders characterized by oxidative stress.
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Affiliation(s)
- Julián Aragonés
- The Center for Transgene Technology and Gene Therapy, Katholieke Universiteit (K.U.) Leuven, Leuven, B-3000, Belgium
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Hébert Chatelain É, Breton S, Lemieux H, Blier PU. Epitoky in Nereis (Neanthes) virens (Polychaeta: Nereididae): A story about sex and death. Comp Biochem Physiol B Biochem Mol Biol 2008; 149:202-8. [DOI: 10.1016/j.cbpb.2007.09.006] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2007] [Revised: 09/11/2007] [Accepted: 09/11/2007] [Indexed: 11/29/2022]
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Lemieux H, Blier P, Tardif JC. Does membrane fatty acid composition modulate mitochondrial functions and their thermal sensitivities? Comp Biochem Physiol A Mol Integr Physiol 2008; 149:20-9. [DOI: 10.1016/j.cbpa.2007.09.015] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2007] [Revised: 09/26/2007] [Accepted: 09/27/2007] [Indexed: 11/25/2022]
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Blier PU, Dutil JD, Lemieux H, Bélanger F, Bitetera L. Phenotypic flexibility of digestive system in Atlantic cod (Gadus morhua). Comp Biochem Physiol A Mol Integr Physiol 2007; 146:174-9. [PMID: 17126579 DOI: 10.1016/j.cbpa.2006.10.012] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [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: 07/10/2006] [Revised: 10/03/2006] [Accepted: 10/08/2006] [Indexed: 10/23/2022]
Abstract
This study examined the restoration of the digestive capacity of Atlantic cod (Gadus morhua Linnaeus) following a long period of food deprivation. Fifty cod (48 cm, 1 kg) were food-deprived for 68 days and then fed in excess with capelin (Mallotus villosus Müller) on alternate days. Ten fish were sampled after 0, 2, 6, 14 and 28 days and the mass of the pyloric caeca, intestine and carcass determined. Two metabolic enzymes (cytochrome c oxidase and citrate synthase) were assayed in white muscle, pyloric caeca and intestine, and trypsin activity was measured in the pyloric caeca. A delay of 14 days was required before body mass started to increase markedly, whereas most of the increase in mass of both the pyloric caeca and intestine relative to fish length occurred earlier in the experiment. By day 14, the activities of trypsin and citrate synthase in the pyloric caeca as well as citrate synthase in the intestine had reached maxima. The growth of the digestive tissues and restoration of their metabolic capacities thus occur early upon refeeding and are likely required for recovery growth to take place. The phenotypic flexibility of the cod digestive system is therefore remarkable: increases in trypsin activity and size of pyloric caeca resulted in a combined 29-fold increase in digestive capacity of the fish during the refeeding period. Our study suggests that Atlantic cod are able to cope with marked fluctuations in food availability in their environment by making a rapid adjustment of their digestive capacity as soon as food availability increases.
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Affiliation(s)
- P U Blier
- Laboratoire de Biologie Intégrative, Département de Biologie, Université du Québec à Rimouski, 300 Allée des Ursulines, Rimouski, Québec, Canada G5L 3A1.
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Blier PU, Breton S, Desrosiers V, Lemieux H. Functional conservatism in mitochondrial evolution: insight from hybridization of arctic and brook charrs. J Exp Zool 2006; 306:425-32. [PMID: 16404737 DOI: 10.1002/jez.b.21089] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
To assess the potential adaptive value of mtDNA, we evaluated functional properties and thermal sensitivity of key mitochondrial enzymes in two species that have originally evolved in different thermal environments (arctic charr, Salvelinus alpinus, and brook charr, S. fontinalis), as well as in their hybrids. We measured the activity of two enzymes of the electron transport system (cytochrome c oxidase and NADH-ubiquinone oxidoreductase), one enzyme of the mitochondrial matrix (citrate synthase), and one enzyme of the anaerobic glycolysis (lactate dehydrogenase) in the red muscle at three temperatures (6 degrees C, 12 degrees C and 18 degrees C). Surprisingly, the species presented no significant differences in enzyme activity, thermal sensitivity or thermostability of key metabolic enzymes even though they evolved in different thermal environments and present important differences in amino acid sequences. It seems that amino acid substitutions between those species have minor impact on the functional properties of mitochondrial enzymes studied. The thermal sensitivity results (Q(10)) obtained for inner-membrane mitochondrial enzymes differed somewhat from those of mitochondrial matrix or cytosolic enzymes. This result indicates the modulation of thermal sensitivity of all mitochondrial inner-membrane processes by a common parameter, which could be the structural and functional properties of membrane phospholipids.
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Affiliation(s)
- Pierre U Blier
- Laboratoire de Biologie Evolutive, Université du Québec à Rimouski, 300 Allée des Ursulines, Rimouski, Que., Canada G5L 3A1.
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Lemieux H, Le François NR, Blier PU. The early ontogeny of digestive and metabolic enzyme activities in two commercial strains of arctic charr (Salvelinus alpinus L.). J Exp Zool A Comp Exp Biol 2003; 299:151-60. [PMID: 12975803 DOI: 10.1002/jez.a.10298] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
The extent to which growth performance is linked to digestive or energetic capacities in the early life stages of a salmonid species was investigated. We compared two strains of Arctic charr known to have different growth potentials during their early development (Fraser and Yukon gold). Trypsin, lipase, and amylase activities of whole alevins were measured at regular intervals from hatching through 65 days of development. To assess catabolic ability, we also measured five enzymes representing the following metabolic pathways: amino acid oxidation (amino aspartate transferase), fatty acid oxidation (beta-hydroxy acyl CoA-dehydrogenase), tricarboxylic acid cycle (citrate synthase), glycolysis (pyruvate kinase), and anaerobic glycolysis (lactate dehydrogenase). The measurement of these enzyme activities in individual fish allowed a clear evaluation of digestive capacity in relation to energetic demand. We also compared triploid and diploid individuals within the Yukon gold strain. For the whole experimental period, diploid Yukon gold fish exhibited the highest growth rate (1.08+/-0.18% length/day) followed by triploid Yukon gold fish (1.00+/-0.28% length/day) and finally Fraser strain fish (0.84+/-0.28% length/day). When differences in enzyme activities were observed, the Fraser strain showed higher enzyme activities at a given length than the Yukon gold strain (diploid and triploid). Higher growth performance appears to be linked to lower metabolic capacity. Our results suggest that fish may have to reach an important increase in the ratio of digestive to catabolic enzyme activities or a leveling off of metabolic enzyme activities before the onset of large increases in mass.
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Affiliation(s)
- Hélène Lemieux
- Laboratoire de Biologie Evolutive, Université du Québec à Rimouski, 300 allée des Ursulines, Rimouski, Québec, Canada, G5L 3A1
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Marazanof M, Thiessard F, Laffort P, Lemieux H, Chene G, Bonnet J, Roudaut R. [Aortic atheroma: not a sensitive indicators for coronary artery disease in patients with mitral valve disease]. Arch Mal Coeur Vaiss 2001; 94:563-8. [PMID: 11480153] [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: 02/20/2023]
Abstract
Aortic atheroma detected by transoesophageal echocardiography has been reported to be a good prognostic marker for coronary disease on angiography. The value of this detection in valvular heart disease would be to avoid preoperative coronary angiography in asymptomatic patients. The aim of this study was to assess the prognostic value of aortic atheroma in a population with a low prevalence of coronary artery disease in whom transoesophageal echocardiography was systematically performed. In addition, calcification of the aortic knuckle, a marker of atherosclerosis, was analysed by simple chest X-ray. One hundred and ninety two patients (103 men, 89 women; mean age: 63.1 +/- 15 years), operated for mitral valve replacement, underwent transoesophageal echocardiography, angiography, within 6 months, and chest X-ray. The cardiovascular risk factors, presence of aortic atherome, angiographic coronary artery disease and aortic calcification were studied. Aortic atheroma was observed in 72 patients (37.5%), usually in the descending thoracic aorta (73.6%). Coronary stenosis was observed in 36 patients (18.7%). On univariate analysis, aortic atherome predicted coronary stenosis with a sensitivity of 53%, specificity of 66% and positive predictive value of 26% and negative predictive value of 86%, compared with chest X-ray: 71%, 65%, 33% and 90%, respectively. In multivariate analysis, only hypercholesterolaemia, smoking and age predicted the presence of coronary artery disease. The presence of aortic atheroma was not predictive (p = 0.3). The authors conclude that aortic atheroma does not predict the presence of coronary artery disease in a patient population with mitral valve disease and a low prevalence of coronary artery disease. Simple chest X-ray has almost the same diagnostic value. The association of these two investigations does not give sufficient negative predictive values to avoid coronary angiography.
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Affiliation(s)
- M Marazanof
- Service d'information médicale, hôpital Pellegrin, place Amélie-Raba-Léon, 33 000 Bordeaux
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