1
|
Maas CCHM, Kent DM, Hughes MC, Dekker R, Lingsma HF, van Klaveren D. Performance metrics for models designed to predict treatment effect. BMC Med Res Methodol 2023; 23:165. [PMID: 37422647 PMCID: PMC10329397 DOI: 10.1186/s12874-023-01974-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Accepted: 06/10/2023] [Indexed: 07/10/2023] Open
Abstract
BACKGROUND Measuring the performance of models that predict individualized treatment effect is challenging because the outcomes of two alternative treatments are inherently unobservable in one patient. The C-for-benefit was proposed to measure discriminative ability. However, measures of calibration and overall performance are still lacking. We aimed to propose metrics of calibration and overall performance for models predicting treatment effect in randomized clinical trials (RCTs). METHODS Similar to the previously proposed C-for-benefit, we defined observed pairwise treatment effect as the difference between outcomes in pairs of matched patients with different treatment assignment. We match each untreated patient with the nearest treated patient based on the Mahalanobis distance between patient characteristics. Then, we define the Eavg-for-benefit, E50-for-benefit, and E90-for-benefit as the average, median, and 90th quantile of the absolute distance between the predicted pairwise treatment effects and local-regression-smoothed observed pairwise treatment effects. Furthermore, we define the cross-entropy-for-benefit and Brier-for-benefit as the logarithmic and average squared distance between predicted and observed pairwise treatment effects. In a simulation study, the metric values of deliberately "perturbed models" were compared to those of the data-generating model, i.e., "optimal model". To illustrate these performance metrics, different modeling approaches for predicting treatment effect are applied to the data of the Diabetes Prevention Program: 1) a risk modelling approach with restricted cubic splines; 2) an effect modelling approach including penalized treatment interactions; and 3) the causal forest. RESULTS As desired, performance metric values of "perturbed models" were consistently worse than those of the "optimal model" (Eavg-for-benefit ≥ 0.043 versus 0.002, E50-for-benefit ≥ 0.032 versus 0.001, E90-for-benefit ≥ 0.084 versus 0.004, cross-entropy-for-benefit ≥ 0.765 versus 0.750, Brier-for-benefit ≥ 0.220 versus 0.218). Calibration, discriminative ability, and overall performance of three different models were similar in the case study. The proposed metrics were implemented in a publicly available R-package "HTEPredictionMetrics". CONCLUSION The proposed metrics are useful to assess the calibration and overall performance of models predicting treatment effect in RCTs.
Collapse
Affiliation(s)
- C C H M Maas
- Department of Public Health, Erasmus University Medical Center, Doctor Molewaterplein 40, 3015 GD, Rotterdam, Netherlands.
| | - D M Kent
- Predictive Analytics and Comparative Effectiveness Center, Institute for Clinical Research and Health Policy Studies, Tufts Medical Center, Boston, USA
| | - M C Hughes
- Predictive Analytics and Comparative Effectiveness Center, Institute for Clinical Research and Health Policy Studies, Tufts Medical Center, Boston, USA
| | - R Dekker
- Erasmus School of Economics, Erasmus University Rotterdam, Rotterdam, Netherlands
| | - H F Lingsma
- Department of Public Health, Erasmus University Medical Center, Doctor Molewaterplein 40, 3015 GD, Rotterdam, Netherlands
| | - D van Klaveren
- Department of Public Health, Erasmus University Medical Center, Doctor Molewaterplein 40, 3015 GD, Rotterdam, Netherlands
- Predictive Analytics and Comparative Effectiveness Center, Institute for Clinical Research and Health Policy Studies, Tufts Medical Center, Boston, USA
| |
Collapse
|
2
|
Hughes MC, Abd-Elsayed A. Ion Channel Myotonias, Myotonia Congenita, and Acquired Neuromyotonia. Advanced Anesthesia Review 2023:523-C201.P21. [DOI: 10.1093/med/9780197584521.003.0201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/01/2023]
Abstract
Abstract
Myotonia congenita (MG) and various ion channel myotonias all fall under the umbrella of nondystrophic myotonias (NDMs) and are distinct from myotonic dystrophy because they are caused by dysfunction of key skeletal muscle ion channels alone without any other systemic effects. NDMs are characterized by electrical myotonia, “defined as the prolongation of skeletal muscle relaxation time following sudden voluntary contraction or external mechanical stimulation.” Hyperexcitability of muscles is central to all of these disease states. The NDMs are divided into two groups: the chloride channelopathies (myotonia congenita) and the sodium channelopathies (paramyotonia congenita [PMC] and the potassium-aggravated myotonias [PAMs]). In contrast, acquired neuromyotonia is an autoimmune disease where approximately 40% of affected individuals have antibodies to voltage-gated potassium channels (VGKCs) that directly affect the neuromuscular junction.
Collapse
|
3
|
Hughes MC, Abd-Elsayed A. Congenital and Acquired Factor Deficiencies. Advanced Anesthesia Review 2023:454-C173.S8. [DOI: 10.1093/med/9780197584521.003.0172] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/01/2023]
Abstract
Abstract
Coagulation factor deficiencies can be either congenital or acquired. Hemophilia is possibly the most recognized type of factor deficiency, but it is certainly not the only one. Hemophilia comes in three forms, two of which are quite well known: A and B. Hemophilia A is an inherited factor VIII deficiency and is an X-linked recessive disorder. Hemophilia B is an inherited deficiency of factor IX and is also an X-linked recessive disorder. The lesser known, hemophilia C, is an inherited deficiency of factor XI. Acquired factor deficiencies are most commonly the formation of an autoantibody to factor VIII; they are sometimes referred to as “acquired hemophilia”; however, in an effort to minimize confusion, they are typically referred to as “acquired factor inhibitor” or “acquired factor deficiency.”
Collapse
|
4
|
Bellissimo CA, Delfinis LJ, Hughes MC, Turnbull PC, Gandhi S, DiBenedetto SN, Rahman FA, Tadi P, Amaral CA, Dehghani A, Cobley J, Quadrilatero J, Schlattner U, Perry CGR. Mitochondrial creatine sensitivity is lost in the D2.mdx model of Duchenne muscular dystrophy and rescued by the mitochondrial-enhancing compound Olesoxime. Am J Physiol Cell Physiol 2023; 324:C1141-C1157. [PMID: 36689672 DOI: 10.1152/ajpcell.00377.2022] [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] [Indexed: 01/25/2023]
Abstract
Duchenne muscular dystrophy (DMD) is associated with distinct mitochondrial stress responses. Here, we aimed to determine whether the prospective mitochondrial-enhancing compound Olesoxime prevents early-stage mitochondrial stress in limb and respiratory muscle from D2.mdx mice using a proof-of-concept short-term regimen spanning 10-28 days of age. As mitochondrial-cytoplasmic energy transfer occurs via ATP- or phosphocreatine-dependent phosphate shuttling, we assessed bioenergetics with or without creatine in vitro. We observed that disruptions in Complex I-supported respiration and H2O2 emission in D2.mdx quadriceps and diaphragm were amplified by creatine demonstrating mitochondrial creatine insensitivity manifests ubiquitously and early in this model. Olesoxime selectively rescued or maintained creatine sensitivity in both muscles, independent of the abundance of respiration-related mitochondrial proteins or mitochondrial creatine kinase cysteine oxidation in quadriceps. Mitochondrial calcium retention capacity and glutathione were altered in a muscle-specific manner in D2.mdx but were generally unchanged by Olesoxime. Treatment reduced serum creatine kinase (muscle damage) and preserved cage hang-time, microCT-based volumes of lean compartments including whole body, hindlimb and bone, recovery of diaphragm force after fatigue, and cross-sectional area of diaphragm type IIX fibre, but reduced type I fibres in quadriceps. Grip strength, voluntary wheel-running and fibrosis were unaltered by Olesoxime. In summary, locomotor and respiratory muscle mitochondrial creatine sensitivities are lost during early stages in D2.mdx mice but are preserved by short-term treatment with Olesoxime in association with specific indices of muscle quality suggesting early myopathy in this model is at least partially attributed to mitochondrial stress.
Collapse
Affiliation(s)
- Catherine A Bellissimo
- School of Kinesiology & Health Science, Muscle Health Research Centre, York University, Toronto, Ontario, Canada
| | - Luca J Delfinis
- https://ror.org/05fq50484York University, Toronto, Ontario, Canada
| | - Meghan C Hughes
- School of Kinesiology and Health Science, https://ror.org/05fq50484York University, Toronto, Canada
| | - Patrick C Turnbull
- School of Kinesiology & Health Sciences, https://ror.org/05fq50484York University, Canada
| | - Shivam Gandhi
- School of Kinesiology &Health Sciences, Muscle Health Research Centre, https://ror.org/05fq50484York University, Toronto, Canada
| | - Sara N DiBenedetto
- School of Kinesiology & Health Sciences, Muscle Health Research Centre, https://ror.org/05fq50484York University, Canada
| | - Fasih A Rahman
- Department of Kinesiology and Health Sciences, https://ror.org/01aff2v68University of Waterloo, Canada
| | - Peyman Tadi
- School of Kinesiology & Health Sciences, https://ror.org/05fq50484York University, Canada
| | - Christina A Amaral
- School of Kinesiology & Health Sciences, https://ror.org/05fq50484York University, Canada
| | - Ali Dehghani
- School of Kinesiology & Health Science, https://ror.org/05fq50484York University, Canada
| | | | - Joe Quadrilatero
- Department of Kinesiology, University of Waterloo, Waterloo, Ontario, Canada, Waterloo, Ontario
| | - Uwe Schlattner
- Fundamental and Applied Bioenergetics, University Grenoble Alpes, Inserm, U1055, Grenoble, France, Grenoble cedex 9, France
| | - Christopher G R Perry
- School of Kinesiology and Health Science, Muscle Health Research Centre (MHRC), Faculty of Health, https://ror.org/05fq50484York University, Toronto, ON, Canada
| |
Collapse
|
5
|
Nederveen JP, Manta K, Bujak AL, Simone AC, Fuda MR, Nilsson MI, Hettinga BP, Hughes MC, Perry CGR, Tarnopolsky MA. A Novel Multi-Ingredient Supplement Activates a Browning Program in White Adipose Tissue and Mitigates Weight Gain in High-Fat Diet-Fed Mice. Nutrients 2021; 13:3726. [PMID: 34835983 PMCID: PMC8623014 DOI: 10.3390/nu13113726] [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] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Revised: 10/11/2021] [Accepted: 10/14/2021] [Indexed: 12/15/2022] Open
Abstract
We investigated the effects of a novel multi-ingredient supplement comprised of polyphenol antioxidants and compounds known to facilitate mitochondrial function and metabolic enhancement (ME) in a mouse model of obesity. In this study, 6-week-old male C57/BL6J mice were placed on a high-fat diet (HFD; ~60% fat) for 6 weeks, with subsequent allocation into experimentalgroups for 4 weeks: HFD control, HFD + ME10 (10 components), HFD + ME7 (7 components), HFD + ME10 + EX, HFD + EX (where '+EX' animals exercised 3 days/week), and chow-fed control. After the intervention, HFD control animals had significantly greater body weight and fat mass. Despite the continuation of HFD, animals supplemented with multi-ingredient ME or who performed exercise training showed an attenuation of fat mass and preservation of lean body mass, which was further enhanced when combined (ME+EX). ME supplementation stimulated the upregulation of white and brown adipose tissue mRNA transcripts associated with mitochondrial biogenesis, browning, fatty acid transport, and fat metabolism. In WAT depots, this was mirrored by mitochodrial oxidative phosphorylation (OXPHOS) protein expression, and increased in vivo fat oxidation measured via CLAMS. ME supplementation also decreased systemic and local inflammation markers. Herein, we demonstrated that novel multi-ingredient nutritional supplements induced significant fat loss independent of physical activity while preserving muscle mass in obese mice. Mechanistically, these MEs appear to act by inducing a browning program in white adipose tissue and decreasing other pathophysiological impairments associated with obesity, including mitochondrial respiration alterations induced by HFD.
Collapse
Affiliation(s)
- Joshua P. Nederveen
- Department of Pediatrics, Faculty of Health Sciences, McMaster University Medical Centre (MUMC), 1200 Main St. W, Hamilton, ON L8N 3Z5, Canada; (J.P.N.); (K.M.); (A.C.S.); (M.R.F.)
| | - Katherine Manta
- Department of Pediatrics, Faculty of Health Sciences, McMaster University Medical Centre (MUMC), 1200 Main St. W, Hamilton, ON L8N 3Z5, Canada; (J.P.N.); (K.M.); (A.C.S.); (M.R.F.)
| | - Adam L. Bujak
- Exerkine Corporation, McMaster University Medical Centre (MUMC), 1200 Main St. W, Hamilton, ON L8N 3Z5, Canada; (A.L.B.); (M.I.N.); (B.P.H.)
| | - Alexander C. Simone
- Department of Pediatrics, Faculty of Health Sciences, McMaster University Medical Centre (MUMC), 1200 Main St. W, Hamilton, ON L8N 3Z5, Canada; (J.P.N.); (K.M.); (A.C.S.); (M.R.F.)
| | - Matthew R. Fuda
- Department of Pediatrics, Faculty of Health Sciences, McMaster University Medical Centre (MUMC), 1200 Main St. W, Hamilton, ON L8N 3Z5, Canada; (J.P.N.); (K.M.); (A.C.S.); (M.R.F.)
| | - Mats I. Nilsson
- Exerkine Corporation, McMaster University Medical Centre (MUMC), 1200 Main St. W, Hamilton, ON L8N 3Z5, Canada; (A.L.B.); (M.I.N.); (B.P.H.)
| | - Bart P. Hettinga
- Exerkine Corporation, McMaster University Medical Centre (MUMC), 1200 Main St. W, Hamilton, ON L8N 3Z5, Canada; (A.L.B.); (M.I.N.); (B.P.H.)
| | - Meghan C. Hughes
- Muscle Health Research Centre (MHRC), School of Kinesiology & Health Science, York University, 4700 Keele Street, Toronto, ON M3J 1P3, Canada; (M.C.H.); (C.G.R.P.)
| | - Christopher G. R. Perry
- Muscle Health Research Centre (MHRC), School of Kinesiology & Health Science, York University, 4700 Keele Street, Toronto, ON M3J 1P3, Canada; (M.C.H.); (C.G.R.P.)
| | - Mark A. Tarnopolsky
- Department of Pediatrics, Faculty of Health Sciences, McMaster University Medical Centre (MUMC), 1200 Main St. W, Hamilton, ON L8N 3Z5, Canada; (J.P.N.); (K.M.); (A.C.S.); (M.R.F.)
- Exerkine Corporation, McMaster University Medical Centre (MUMC), 1200 Main St. W, Hamilton, ON L8N 3Z5, Canada; (A.L.B.); (M.I.N.); (B.P.H.)
| |
Collapse
|
6
|
Avin KG, Hughes MC, Chen NX, Srinivasan S, O’Neill KD, Evan AP, Bacallao RL, Schulte ML, Moorthi RN, Gisch DL, Perry CGR, Moe SM, O’Connell TM. Skeletal muscle metabolic responses to physical activity are muscle type specific in a rat model of chronic kidney disease. Sci Rep 2021; 11:9788. [PMID: 33963215 PMCID: PMC8105324 DOI: 10.1038/s41598-021-89120-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2020] [Accepted: 04/14/2021] [Indexed: 02/03/2023] Open
Abstract
Chronic kidney disease (CKD) leads to musculoskeletal impairments that are impacted by muscle metabolism. We tested the hypothesis that 10-weeks of voluntary wheel running can improve skeletal muscle mitochondria activity and function in a rat model of CKD. Groups included (n = 12-14/group): (1) normal littermates (NL); (2) CKD, and; (3) CKD-10 weeks of voluntary wheel running (CKD-W). At 35-weeks old the following assays were performed in the soleus and extensor digitorum longus (EDL): targeted metabolomics, mitochondrial respiration, and protein expression. Amino acid-related compounds were reduced in CKD muscle and not restored by physical activity. Mitochondrial respiration in the CKD soleus was increased compared to NL, but not impacted by physical activity. The EDL respiration was not different between NL and CKD, but increased in CKD-wheel rats compared to CKD and NL groups. Our results demonstrate that the soleus may be more susceptible to CKD-induced changes of mitochondrial complex content and respiration, while in the EDL, these alterations were in response the physiological load induced by mild physical activity. Future studies should focus on therapies to improve mitochondrial function in both types of muscle to determine if such treatments can improve the ability to adapt to physical activity in CKD.
Collapse
Affiliation(s)
- Keith G. Avin
- Division of Nephrology, Indiana University School of Medicine, 950 W. Walnut St., R2 202, Indianapolis, IN 46202 USA ,Department of Physical Therapy, Indiana University School of Health and Human Sciences, Indianapolis, IN USA ,Roudebush Veterans Affairs Medical Center, Indianapolis, IN USA
| | - Meghan C. Hughes
- School of Kinesiology and Health Science, Muscle Health Research Centre, York University, Toronto, ON Canada
| | - Neal X. Chen
- Division of Nephrology, Indiana University School of Medicine, 950 W. Walnut St., R2 202, Indianapolis, IN 46202 USA ,Roudebush Veterans Affairs Medical Center, Indianapolis, IN USA
| | - Shruthi Srinivasan
- Division of Nephrology, Indiana University School of Medicine, 950 W. Walnut St., R2 202, Indianapolis, IN 46202 USA ,Roudebush Veterans Affairs Medical Center, Indianapolis, IN USA
| | - Kalisha D. O’Neill
- Division of Nephrology, Indiana University School of Medicine, 950 W. Walnut St., R2 202, Indianapolis, IN 46202 USA ,Roudebush Veterans Affairs Medical Center, Indianapolis, IN USA
| | - Andrew P. Evan
- Department of Anatomy and Cell Biology, Indiana University School of Medicine, Indianapolis, IN USA
| | - Robert L. Bacallao
- Division of Nephrology, Indiana University School of Medicine, 950 W. Walnut St., R2 202, Indianapolis, IN 46202 USA ,Roudebush Veterans Affairs Medical Center, Indianapolis, IN USA
| | - Michael L. Schulte
- Department of Radiology and Imaging Sciences, Indiana University School of Medicine, Indianapolis, IN USA
| | - Ranjani N. Moorthi
- Division of Nephrology, Indiana University School of Medicine, 950 W. Walnut St., R2 202, Indianapolis, IN 46202 USA
| | - Debora L. Gisch
- Departamento de Engenharia Mecânica, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS Brazil
| | - Christopher G. R. Perry
- School of Kinesiology and Health Science, Muscle Health Research Centre, York University, Toronto, ON Canada
| | - Sharon M. Moe
- Division of Nephrology, Indiana University School of Medicine, 950 W. Walnut St., R2 202, Indianapolis, IN 46202 USA ,Roudebush Veterans Affairs Medical Center, Indianapolis, IN USA ,Department of Anatomy and Cell Biology, Indiana University School of Medicine, Indianapolis, IN USA
| | - Thomas M. O’Connell
- Department of Otolaryngology, Head and Neck Surgery, Indiana University School of Medicine, Indianapolis, IN USA
| |
Collapse
|
7
|
Hughes MC, Perry SF. Does blood flow limit acute hypoxia performance in larval zebrafish (Danio rerio)? J Comp Physiol B 2021; 191:469-478. [PMID: 33580284 DOI: 10.1007/s00360-020-01331-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [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: 08/18/2020] [Revised: 10/22/2020] [Accepted: 11/18/2020] [Indexed: 01/21/2023]
Abstract
Oxygen uptake (ṀO2) in larval zebrafish prior to maturation of the gill relies on cutaneous O2 transfer. Under normoxic conditions, rates of cutaneous O2 transfer are unaffected by haemoglobin availability but are diminished in fish lacking a functional circulatory system, suggesting that internal convection is critically involved in setting the resting ṀO2 in zebrafish larvae, even when relying on cutaneous O2 transfer. The reliance of ṀO2 on blood circulation led to the first objective of the current study, to determine whether loss of internal convection would reduce acute hypoxia performance (as determined by measuring critical PO2; Pcrit) in larval zebrafish under conditions of moderate hypoxia (PO2 = 55 mmHg) at 28.5 and 34 °C. Internal convection was eliminated by preventing development of blood vessels using morpholino knockdown of vascular endothelial growth factor (VEGF); these fish are termed VEGF morphants. Breathing frequency (fV) and heart rate (fH) also were measured (at 28.5 °C) to determine whether any detriment in performance might be linked to cardiorespiratory dysfunction. Although ṀO2 was reduced in the VEGF morphants, there was no significant effect on Pcrit at 28.5 °C. Raising temperature to 34 °C resulted in the VEGF morphants exhibiting a higher Pcrit than the shams, suggesting an impairment of hypoxia tolerance in the morphants at the higher temperature. The usual robust increase in fV during hypoxia was absent or attenuated in VEGF morphants at 4 and 5 days post fertilization (dpf), respectively. Resting fH was reduced in the VEGF morphants and unlike the sham fish, the morphants did not exhibit hypoxic tachycardia at 4 or 5 dpf. The number of cutaneous neuroepithelial cells (presumptive O2 chemoreceptors) was significantly higher in the VEGF morphants and thus the cardiorespiratory impairment in the morphants during hypoxia was unlikely related to inadequate peripheral O2 sensing.
Collapse
Affiliation(s)
- M C Hughes
- Department of Biology, University of Ottawa, 30 Marie Curie, Ottawa, ON, K1N6N5, Canada
| | - S F Perry
- Department of Biology, University of Ottawa, 30 Marie Curie, Ottawa, ON, K1N6N5, Canada.
| |
Collapse
|
8
|
Bellissimo CA, Delfinis LJ, Hughes MC, Turnbull PC, Gandhi S, DiBenedetto SN, Rahman F, Tadi P, Amaral C, Dehghani A, Quadrilatero J, Schlattner U, Perry CGR. Correction: Muscle health in a mouse model of Duchenne muscular dystrophy can be partially improved by restoring mitochondrial creatine metabolism. Appl Physiol Nutr Metab 2020; 46:190. [PMID: 33356880 DOI: 10.1139/apnm-2020-1066] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Affiliation(s)
- C A Bellissimo
- School of Kinesiology & Health Science, Muscle Health Research Centre, York University, Toronto, ON M3J 1P3, Canada
| | - L J Delfinis
- School of Kinesiology & Health Science, Muscle Health Research Centre, York University, Toronto, ON M3J 1P3, Canada
| | - M C Hughes
- School of Kinesiology & Health Science, Muscle Health Research Centre, York University, Toronto, ON M3J 1P3, Canada
| | - P C Turnbull
- School of Kinesiology & Health Science, Muscle Health Research Centre, York University, Toronto, ON M3J 1P3, Canada
| | - S Gandhi
- School of Kinesiology & Health Science, Muscle Health Research Centre, York University, Toronto, ON M3J 1P3, Canada
| | - S N DiBenedetto
- School of Kinesiology & Health Science, Muscle Health Research Centre, York University, Toronto, ON M3J 1P3, Canada
| | - F Rahman
- Faculty of Applied Health Sciences, Department of Kinesiology, University of Waterloo, Waterloo, Ontario, Canada
| | - P Tadi
- School of Kinesiology & Health Science, Muscle Health Research Centre, York University, Toronto, ON M3J 1P3, Canada
| | - C Amaral
- School of Kinesiology & Health Science, Muscle Health Research Centre, York University, Toronto, ON M3J 1P3, Canada
| | - A Dehghani
- School of Kinesiology & Health Science, Muscle Health Research Centre, York University, Toronto, ON M3J 1P3, Canada
| | - J Quadrilatero
- Faculty of Applied Health Sciences, Department of Kinesiology, University of Waterloo, Waterloo, Ontario, Canada
| | - U Schlattner
- Laboratory of Fundamental and Applied Bioenergetics, and SFR Environmental and Systems Biology, University of Grenoble Alpes, Grenoble, France
| | - C G R Perry
- School of Kinesiology & Health Science, Muscle Health Research Centre, York University, Toronto, ON M3J 1P3, Canada
| |
Collapse
|
9
|
Ramos SV, Hughes MC, Delfinis LJ, Bellissimo CA, Perry CGR. Mitochondrial bioenergetic dysfunction in the D2.mdx model of Duchenne muscular dystrophy is associated with microtubule disorganization in skeletal muscle. PLoS One 2020; 15:e0237138. [PMID: 33002037 PMCID: PMC7529311 DOI: 10.1371/journal.pone.0237138] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [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: 04/07/2019] [Accepted: 07/21/2020] [Indexed: 11/25/2022] Open
Abstract
In Duchenne muscular dystrophy, a lack of dystrophin leads to extensive muscle weakness and atrophy that is linked to cellular metabolic dysfunction and oxidative stress. This dystrophinopathy results in a loss of tethering between microtubules and the sarcolemma. Microtubules are also believed to regulate mitochondrial bioenergetics potentially by binding the outer mitochondrial membrane voltage dependent anion channel (VDAC) and influencing permeability to ADP/ATP cycling. The objective of this investigation was to determine if a lack of dystrophin causes microtubule disorganization concurrent with mitochondrial dysfunction in skeletal muscle, and whether this relationship is linked to altered binding of tubulin to VDAC. In extensor digitorum longus (EDL) muscle from 4-week old D2.mdx mice, microtubule disorganization was observed when probing for α-tubulin. This cytoskeletal disorder was associated with a reduced ability of ADP to stimulate respiration and attenuate H2O2 emission relative to wildtype controls. However, this was not associated with altered α-tubulin-VDAC2 interactions. These findings reveal that microtubule disorganization in dystrophin-deficient EDL is associated with impaired ADP control of mitochondrial bioenergetics, and suggests that mechanisms alternative to α-tubulin’s regulation of VDAC2 should be examined to understand how cytoskeletal disruption in the absence of dystrophin may cause metabolic dysfunctions in skeletal muscle.
Collapse
Affiliation(s)
- Sofhia V. Ramos
- School of Kinesiology and Health Sciences, Muscle Health Research Centre, York University, Toronto, Ontario, Canada
| | - Meghan C. Hughes
- School of Kinesiology and Health Sciences, Muscle Health Research Centre, York University, Toronto, Ontario, Canada
| | - Luca J. Delfinis
- School of Kinesiology and Health Sciences, Muscle Health Research Centre, York University, Toronto, Ontario, Canada
| | - Catherine A. Bellissimo
- School of Kinesiology and Health Sciences, Muscle Health Research Centre, York University, Toronto, Ontario, Canada
| | - Christopher G. R. Perry
- School of Kinesiology and Health Sciences, Muscle Health Research Centre, York University, Toronto, Ontario, Canada
- * E-mail:
| |
Collapse
|
10
|
Hughes MC, Abd-Elsayed A. Implantable Medical Devices: A New Frontier for Security. J Cardiothorac Vasc Anesth 2020; 34:1703-1704. [DOI: 10.1053/j.jvca.2019.11.046] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/19/2019] [Accepted: 11/24/2019] [Indexed: 11/11/2022]
|
11
|
Monaco CMF, Hughes MC, Ramos SV, Varah NE, Lamberz C, Rahman FA, McGlory C, Tarnopolsky MA, Krause MP, Laham R, Hawke TJ, Perry CGR. Correction to: Altered mitochondrial bioenergetics and ultrastructure in the skeletal muscle of young adults with type 1 diabetes. Diabetologia 2020; 63:887-888. [PMID: 31993715 DOI: 10.1007/s00125-020-05092-w] [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] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
In Fig. 1e the rate of mitochondrial H2O2 emission was incorrectly shown as being per second rather than per minute.
Collapse
Affiliation(s)
- Cynthia M F Monaco
- Department of Pathology and Molecular Medicine, McMaster University, 4N65 Health Sciences Centre, 1200 Main Street West, Hamilton, ON, L8N 3Z5, Canada
| | - Meghan C Hughes
- School of Kinesiology and Health Sciences, Muscle Health Research Centre, York University, Toronto, ON, Canada
| | - Sofhia V Ramos
- School of Kinesiology and Health Sciences, Muscle Health Research Centre, York University, Toronto, ON, Canada
| | - Nina E Varah
- Department of Pathology and Molecular Medicine, McMaster University, 4N65 Health Sciences Centre, 1200 Main Street West, Hamilton, ON, L8N 3Z5, Canada
| | | | - Fasih A Rahman
- Department of Kinesiology, University of Windsor, Windsor, ON, Canada
| | - Chris McGlory
- Department of Kinesiology, McMaster University, Hamilton, ON, Canada
| | | | - Matthew P Krause
- Department of Kinesiology, University of Windsor, Windsor, ON, Canada
| | - Robert Laham
- School of Kinesiology and Health Sciences, Muscle Health Research Centre, York University, Toronto, ON, Canada
| | - Thomas J Hawke
- Department of Pathology and Molecular Medicine, McMaster University, 4N65 Health Sciences Centre, 1200 Main Street West, Hamilton, ON, L8N 3Z5, Canada.
| | - Christopher G R Perry
- School of Kinesiology and Health Sciences, Muscle Health Research Centre, York University, Toronto, ON, Canada
| |
Collapse
|
12
|
Monaco CMF, Bellissimo CA, Hughes MC, Ramos SV, Laham R, Perry CGR, Hawke TJ. Sexual dimorphism in human skeletal muscle mitochondrial bioenergetics in response to type 1 diabetes. Am J Physiol Endocrinol Metab 2020; 318:E44-E51. [PMID: 31794260 PMCID: PMC6985789 DOI: 10.1152/ajpendo.00411.2019] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Sexual dimorphism in mitochondrial respiratory function has been reported in young women and men without diabetes, which may have important implications for exercise. The purpose of this study was to determine if sexual dimorphism exists in skeletal muscle mitochondrial bioenergetics in people with type 1 diabetes (T1D). A resting muscle microbiopsy was obtained from women and men with T1D (n = 10/8, respectively) and without T1D (control; n = 8/7, respectively). High-resolution respirometry and spectrofluorometry were used to measure mitochondrial respiratory function, hydrogen peroxide (mH2O2) emission and calcium retention capacity (mCRC) in permeabilized myofiber bundles. The impact of T1D on mitochondrial bioenergetics between sexes was interrogated by comparing the change between women and men with T1D relative to the average values of their respective sex-matched controls (i.e., delta). These aforementioned analyses revealed that men with T1D have increased skeletal muscle mitochondrial complex I sensitivity but reduced complex II sensitivity and capacity in comparison to women with T1D. mH2O2 emission was lower in women compared with men with T1D at the level of complex I (succinate driven), whereas mCRC and mitochondrial protein content remained similar between sexes. In conclusion, women and men with T1D exhibit differential responses in skeletal muscle mitochondrial bioenergetics. Although larger cohort studies are certainly required, these early findings nonetheless highlight the importance of considering sex as a variable in the care and treatment of people with T1D (e.g., benefits of different exercise prescriptions).
Collapse
Affiliation(s)
- Cynthia M F Monaco
- Department of Pathology and Molecular Medicine, McMaster University, Health Sciences Centre, Hamilton, Ontario, Canada
| | - Catherine A Bellissimo
- School of Kinesiology and Health Sciences, Muscle Health Research Centre, York University, Toronto, Ontario, Canada
| | - Meghan C Hughes
- School of Kinesiology and Health Sciences, Muscle Health Research Centre, York University, Toronto, Ontario, Canada
| | - Sofhia V Ramos
- School of Kinesiology and Health Sciences, Muscle Health Research Centre, York University, Toronto, Ontario, Canada
| | - Robert Laham
- School of Kinesiology and Health Sciences, Muscle Health Research Centre, York University, Toronto, Ontario, Canada
| | - Christopher G R Perry
- School of Kinesiology and Health Sciences, Muscle Health Research Centre, York University, Toronto, Ontario, Canada
| | - Thomas J Hawke
- Department of Pathology and Molecular Medicine, McMaster University, Health Sciences Centre, Hamilton, Ontario, Canada
| |
Collapse
|
13
|
Turnbull PC, Hughes MC, Perry CGR. The fatty acid derivative palmitoylcarnitine abrogates colorectal cancer cell survival by depleting glutathione. Am J Physiol Cell Physiol 2019; 317:C1278-C1288. [PMID: 31483701 DOI: 10.1152/ajpcell.00319.2019] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Previous evidence suggests that palmitoylcarnitine incubations trigger mitochondrial-mediated apoptosis in HT29 colorectal adenocarcinoma cells, yet nontransformed cells appear insensitive. The mechanism by which palmitoylcarnitine induces cancer cell death is unclear. The purpose of this investigation was to examine the relationship between mitochondrial kinetics and glutathione buffering in determining the effect of palmitoylcarnitine on cell survival. HT29 and HCT 116 colorectal adenocarcinoma cells, CCD 841 nontransformed colon cells, and MCF7 breast adenocarcinoma cells were exposed to 0 μM, 50 μM, and 100 μM palmitoylcarnitine for 24-48 h. HCT 116 and HT29 cells showed decreased cell survival following palmitoylcarnitine compared with CCD 841 cells. Palmitoylcarnitine stimulated H2O2 emission in HT29 and CCD 841 cells but increased it to a greater level in HT29 cells due largely to a higher basal H2O2 emission. This greater H2O2 emission was associated with lower glutathione buffering capacity and caspase-3 activation in HT29 cells. The glutathione-depleting agent buthionine sulfoximine sensitized CCD 841 cells and further sensitized HT29 cells to palmitoylcarnitine-induced decreases in cell survival. MCF7 cells did not produce H2O2 when exposed to palmitoylcarnitine and were able to maintain glutathione levels. Furthermore, HT29 cells demonstrated the lowest mitochondrial oxidative kinetics vs. CCD 841 and MCF7 cells. The results demonstrate that colorectal cancer is sensitive to palmitoylcarnitine due in part to an inability to prevent oxidative stress through glutathione-redox coupling, thereby rendering the cells sensitive to elevations in H2O2. These findings suggest that the relationship between inherent metabolic capacities and redox regulation is altered early in response to palmitoylcarnitine.
Collapse
Affiliation(s)
- Patrick C Turnbull
- School of Kinesiology and Health Science, Muscle Health Research Centre, York University, Toronto, Ontario, Canada
| | - Meghan C Hughes
- School of Kinesiology and Health Science, Muscle Health Research Centre, York University, Toronto, Ontario, Canada
| | - Christopher G R Perry
- School of Kinesiology and Health Science, Muscle Health Research Centre, York University, Toronto, Ontario, Canada
| |
Collapse
|
14
|
Hughes MC, Ramos SV, Turnbull PC, Rebalka IA, Cao A, Monaco CM, Varah NE, Edgett BA, Huber JS, Tadi P, Delfinis LJ, Schlattner U, Simpson JA, Hawke TJ, Perry CG. Early myopathy in Duchenne muscular dystrophy is associated with elevated mitochondrial H 2 O 2 emission during impaired oxidative phosphorylation. J Cachexia Sarcopenia Muscle 2019; 10:643-661. [PMID: 30938481 PMCID: PMC6596403 DOI: 10.1002/jcsm.12405] [Citation(s) in RCA: 57] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/02/2018] [Revised: 12/13/2018] [Accepted: 01/09/2019] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND Muscle wasting and weakness in Duchenne muscular dystrophy (DMD) causes severe locomotor limitations and early death due in part to respiratory muscle failure. Given that current clinical practice focuses on treating secondary complications in this genetic disease, there is a clear need to identify additional contributions in the aetiology of this myopathy for knowledge-guided therapy development. Here, we address the unresolved question of whether the complex impairments observed in DMD are linked to elevated mitochondrial H2 O2 emission in conjunction with impaired oxidative phosphorylation. This study performed a systematic evaluation of the nature and degree of mitochondrial-derived H2 O2 emission and mitochondrial oxidative dysfunction in a mouse model of DMD by designing in vitro bioenergetic assessments that attempt to mimic in vivo conditions known to be critical for the regulation of mitochondrial bioenergetics. METHODS Mitochondrial bioenergetics were compared with functional and histopathological indices of myopathy early in DMD (4 weeks) in D2.B10-DMDmdx /2J mice (D2.mdx)-a model that demonstrates severe muscle weakness. Adenosine diphosphate's (ADP's) central effect of attenuating H2 O2 emission while stimulating respiration was compared under two models of mitochondrial-cytoplasmic phosphate exchange (creatine independent and dependent) in muscles that stained positive for membrane damage (diaphragm, quadriceps, and white gastrocnemius). RESULTS Pathway-specific analyses revealed that Complex I-supported maximal H2 O2 emission was elevated concurrent with a reduced ability of ADP to attenuate emission during respiration in all three muscles (mH2 O2 : +17 to +197% in D2.mdx vs. wild type). This was associated with an impaired ability of ADP to stimulate respiration at sub-maximal and maximal kinetics (-17 to -72% in D2.mdx vs. wild type), as well as a loss of creatine-dependent mitochondrial phosphate shuttling in diaphragm and quadriceps. These changes largely occurred independent of mitochondrial density or abundance of respiratory chain complexes, except for quadriceps. This muscle was also the only one exhibiting decreased calcium retention capacity, which indicates increased sensitivity to calcium-induced permeability transition pore opening. Increased H2 O2 emission was accompanied by a compensatory increase in total glutathione, while oxidative stress markers were unchanged. Mitochondrial bioenergetic dysfunctions were associated with induction of mitochondrial-linked caspase 9, necrosis, and markers of atrophy in some muscles as well as reduced hindlimb torque and reduced respiratory muscle function. CONCLUSIONS These results provide evidence that Complex I dysfunction and loss of central respiratory control by ADP and creatine cause elevated oxidant generation during impaired oxidative phosphorylation. These dysfunctions may contribute to early stage disease pathophysiology and support the growing notion that mitochondria are a potential therapeutic target in this disease.
Collapse
Affiliation(s)
- Meghan C. Hughes
- School of Kinesiology and Health Science, Muscle Health Research Centre, 344 Norman Bethune CollegeYork UniversityTorontoONCanada
| | - Sofhia V. Ramos
- School of Kinesiology and Health Science, Muscle Health Research Centre, 344 Norman Bethune CollegeYork UniversityTorontoONCanada
| | - Patrick C. Turnbull
- School of Kinesiology and Health Science, Muscle Health Research Centre, 344 Norman Bethune CollegeYork UniversityTorontoONCanada
| | - Irena A. Rebalka
- Department of Pathology and Molecular MedicineMcMaster UniversityHamiltonONCanada
| | - Andrew Cao
- Department of Pathology and Molecular MedicineMcMaster UniversityHamiltonONCanada
| | - Cynthia M.F. Monaco
- Department of Pathology and Molecular MedicineMcMaster UniversityHamiltonONCanada
| | - Nina E. Varah
- Department of Pathology and Molecular MedicineMcMaster UniversityHamiltonONCanada
| | - Brittany A. Edgett
- Department of Human Health and Nutritional Sciences and Cardiovascular Research GroupUniversity of GuelphGuelphONCanada
| | - Jason S. Huber
- Department of Human Health and Nutritional Sciences and Cardiovascular Research GroupUniversity of GuelphGuelphONCanada
| | - Peyman Tadi
- School of Kinesiology and Health Science, Muscle Health Research Centre, 344 Norman Bethune CollegeYork UniversityTorontoONCanada
| | - Luca J. Delfinis
- School of Kinesiology and Health Science, Muscle Health Research Centre, 344 Norman Bethune CollegeYork UniversityTorontoONCanada
| | - U. Schlattner
- Laboratory of Fundamental and Applied Bioenergetics (LBFA) and SFR Environmental and Systems Biology (BEeSy)University Grenoble AlpesGrenobleFrance
| | - Jeremy A. Simpson
- Department of Human Health and Nutritional Sciences and Cardiovascular Research GroupUniversity of GuelphGuelphONCanada
| | - Thomas J. Hawke
- Department of Pathology and Molecular MedicineMcMaster UniversityHamiltonONCanada
| | - Christopher G.R. Perry
- School of Kinesiology and Health Science, Muscle Health Research Centre, 344 Norman Bethune CollegeYork UniversityTorontoONCanada
| |
Collapse
|
15
|
Hughes MC, Ramos SV, Turnbull PC, Perry CGR. Advanced Stages of Duchenne Muscular Dystrophy Exhibit Mitochondrial Bioenergetic Impairments Linked Specifically to Creatine‐Dependent Energy Exchange. FASEB J 2019. [DOI: 10.1096/fasebj.2019.33.1_supplement.868.14] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Meghan C Hughes
- School of Kinesiology and Health Science and the Muscle Health Research CentreYork UniversityTorontoONCanada
| | - Sofhia V Ramos
- School of Kinesiology and Health Science and the Muscle Health Research CentreYork UniversityTorontoONCanada
| | - Patrick C Turnbull
- School of Kinesiology and Health Science and the Muscle Health Research CentreYork UniversityTorontoONCanada
| | - Christopher G R Perry
- School of Kinesiology and Health Science and the Muscle Health Research CentreYork UniversityTorontoONCanada
| |
Collapse
|
16
|
Ramos SV, Hughes MC, Bellissimo CA, Perry CGR. Mitochondrial Dysfunction and Disorganized Microtubules in Duchenne Muscular Dystrophy are Not Related to Altered α Tubulin‐Voltage Dependent Anion Channel (VDAC) 2 Interactions. FASEB J 2019. [DOI: 10.1096/fasebj.2019.33.1_supplement.868.27] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Sofhia V Ramos
- School of Kinesiology and Health ScienceYork UniversityTorontoONCanada
| | - Meghan C Hughes
- School of Kinesiology and Health ScienceYork UniversityTorontoONCanada
| | | | | |
Collapse
|
17
|
Ramos SV, Hughes MC, Perry CGR. Altered Skeletal Muscle Microtubule‐Mitochondrial Voltage Gated‐Dependent Anion Channel (VDAC) 2 Binding is Related to Bioenergetic Impairments after Paclitaxel but not Vinblastine Chemotherapies. FASEB J 2019. [DOI: 10.1096/fasebj.2019.33.1_supplement.868.7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
|
18
|
Hughes MC, Ramos SV, Turnbull PC, Edgett BA, Huber JS, Polidovitch N, Schlattner U, Backx PH, Simpson JA, Perry CGR. Impairments in left ventricular mitochondrial bioenergetics precede overt cardiac dysfunction and remodelling in Duchenne muscular dystrophy. J Physiol 2019; 598:1377-1392. [PMID: 30674086 DOI: 10.1113/jp277306] [Citation(s) in RCA: 21] [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] [Received: 10/13/2018] [Accepted: 01/22/2019] [Indexed: 12/21/2022] Open
Abstract
KEY POINTS Ninety-eight per cent of patients with Duchenne muscular dystrophy (DMD) develop cardiomyopathy, with 40% developing heart failure. While increased propensity for mitochondrial induction of cell death has been observed in left ventricle, it remains unknown whether this is linked to impaired mitochondrial respiratory control and elevated H2 O2 emission prior to the onset of cardiomyopathy. Classic mouse models of DMD demonstrate hyper-regeneration in skeletal muscle which may mask mitochondrial abnormalities. Using a model with less regenerative capacity that is more akin to DMD patients, we observed elevated left ventricular mitochondrial H2 O2 and impaired oxidative phosphorylation in the absence of cardiac remodelling or overt cardiac dysfunction at 4 weeks. These impairments were associated with dysfunctions at complex I, governance by ADP and creatine-dependent phosphate shuttling, which results in a less efficient response to energy demands. Mitochondria may be a therapeutic target for the treatment of cardiomyopathy in DMD. ABSTRACT In Duchenne muscular dystrophy (DMD), mitochondrial dysfunction is predicted as a response to numerous cellular stressors, yet the contribution of mitochondria to the onset of cardiomyopathy remains unknown. To resolve this uncertainty, we designed in vitro assessments of mitochondrial bioenergetics to model mitochondrial control parameters that influence cardiac function. Both left ventricular mitochondrial responsiveness to the central bioenergetic controller ADP and the ability of creatine to facilitate mitochondrial-cytoplasmic phosphate shuttling were assessed. These measurements were performed in D2.B10-DMDmdx /2J mice - a model that demonstrates skeletal muscle atrophy and weakness due to limited regenerative capacities and cardiomyopathy more akin to people with DMD than classic models. At 4 weeks of age, there was no evidence of cardiac remodelling or cardiac dysfunction despite impairments in ADP-stimulated respiration and ADP attenuation of H2 O2 emission. These impairments were seen at both submaximal and maximal ADP concentrations despite no reductions in mitochondrial content markers. The ability of creatine to enhance ADP's control of mitochondrial bioenergetics was also impaired, suggesting an impairment in mitochondrial creatine kinase-dependent phosphate shuttling. Susceptibly to permeability transition pore opening and the subsequent activation of cell death pathways remained unchanged. Mitochondrial H2 O2 emission was elevated despite no change in markers of irreversible oxidative damage, suggesting alternative redox signalling mechanisms should be explored. These findings demonstrate that selective mitochondrial dysfunction precedes the onset of overt cardiomyopathy in D2.mdx mice, suggesting that improving mitochondrial bioenergetics by restoring ADP, creatine-dependent phosphate shuttling and complex I should be considered for treating DMD patients.
Collapse
Affiliation(s)
- Meghan C Hughes
- School of Kinesiology and Health Science and the Muscle Health Research Centre, York University, Toronto, ON, Canada
| | - Sofhia V Ramos
- School of Kinesiology and Health Science and the Muscle Health Research Centre, York University, Toronto, ON, Canada
| | - Patrick C Turnbull
- School of Kinesiology and Health Science and the Muscle Health Research Centre, York University, Toronto, ON, Canada
| | - Brittany A Edgett
- Department of Human Health and Nutritional Sciences and Cardiovascular Research Group, University of Guelph, Guelph, ON, Canada.,Department of Pharmacology, Dalhousie Medicine New Brunswick, Saint John, New Brunswick, Canada.,IMPART Team Canada Investigator Network, Saint John, New Brunswick, Canada
| | - Jason S Huber
- Department of Human Health and Nutritional Sciences and Cardiovascular Research Group, University of Guelph, Guelph, ON, Canada
| | - Nazari Polidovitch
- Department of Biology and the Muscle Health Research Centre, York University, Toronto, ON, Canada
| | - Uwe Schlattner
- Laboratory of Fundamental and Applied Bioenergetics (LBFA) and SFR Environmental and Systems Biology (BEeSy), University Grenoble Alpes, Grenoble, France
| | - Peter H Backx
- Department of Biology and the Muscle Health Research Centre, York University, Toronto, ON, Canada
| | - Jeremy A Simpson
- Department of Human Health and Nutritional Sciences and Cardiovascular Research Group, University of Guelph, Guelph, ON, Canada.,IMPART Team Canada Investigator Network, Saint John, New Brunswick, Canada
| | - Christopher G R Perry
- School of Kinesiology and Health Science and the Muscle Health Research Centre, York University, Toronto, ON, Canada
| |
Collapse
|
19
|
Ramos SV, Hughes MC, Perry CGR. Altered skeletal muscle microtubule-mitochondrial VDAC2 binding is related to bioenergetic impairments after paclitaxel but not vinblastine chemotherapies. Am J Physiol Cell Physiol 2019; 316:C449-C455. [PMID: 30624982 DOI: 10.1152/ajpcell.00384.2018] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [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: 11/22/2022]
Abstract
Microtubule-targeting chemotherapies are linked to impaired cellular metabolism, which may contribute to skeletal muscle dysfunction. However, the mechanisms by which metabolic homeostasis is perturbed remains unknown. Tubulin, the fundamental unit of microtubules, has been implicated in the regulation of mitochondrial-cytosolic ADP/ATP exchange through its interaction with the outer membrane voltage-dependent anion channel (VDAC). Based on this model, we predicted that disrupting microtubule architecture with the stabilizer paclitaxel and destabilizer vinblastine would impair skeletal muscle mitochondrial bioenergetics. Here, we provide in vitro evidence of a direct interaction between both α-tubulin and βII-tubulin with VDAC2 in untreated single extensor digitorum longus (EDL) fibers. Paclitaxel increased both α- and βII-tubulin-VDAC2 interactions, whereas vinblastine had no effect. Utilizing a permeabilized muscle fiber bundle preparation that retains the cytoskeleton, paclitaxel treatment impaired the ability of ADP to attenuate H2O2 emission, resulting in greater H2O2 emission kinetics. Despite no effect on tubulin-VDAC2 binding, vinblastine still altered mitochondrial bioenergetics through a surprising increase in ADP-stimulated respiration while also impairing ADP suppression of H2O2 and increasing mitochondrial susceptibility to calcium-induced formation of the proapoptotic permeability transition pore. Collectively, these results demonstrate that altering microtubule architecture with chemotherapeutics disrupts mitochondrial bioenergetics in EDL skeletal muscle. Specifically, microtubule stabilization increases H2O2 emission by impairing ADP sensitivity in association with greater tubulin-VDAC binding. In contrast, decreasing microtubule abundance triggers a broad impairment of ADP's governance of respiration and H2O2 emission as well as calcium retention capacity, albeit through an unknown mechanism.
Collapse
Affiliation(s)
- Sofhia V Ramos
- School of Kinesiology and Health Science, Muscle Health Research Centre, York University , Toronto, Ontario , Canada
| | - Meghan C Hughes
- School of Kinesiology and Health Science, Muscle Health Research Centre, York University , Toronto, Ontario , Canada
| | - Christopher G R Perry
- School of Kinesiology and Health Science, Muscle Health Research Centre, York University , Toronto, Ontario , Canada
| |
Collapse
|
20
|
Monaco CMF, Hughes MC, Ramos SV, Varah NE, Lamberz C, Rahman FA, McGlory C, Tarnopolsky MA, Krause MP, Laham R, Hawke TJ, Perry CGR. Altered mitochondrial bioenergetics and ultrastructure in the skeletal muscle of young adults with type 1 diabetes. Diabetologia 2018; 61:1411-1423. [PMID: 29666899 DOI: 10.1007/s00125-018-4602-6] [Citation(s) in RCA: 64] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/08/2017] [Accepted: 02/28/2018] [Indexed: 02/06/2023]
Abstract
AIMS/HYPOTHESIS A comprehensive assessment of skeletal muscle ultrastructure and mitochondrial bioenergetics has not been undertaken in individuals with type 1 diabetes. This study aimed to systematically assess skeletal muscle mitochondrial phenotype in young adults with type 1 diabetes. METHODS Physically active, young adults (men and women) with type 1 diabetes (HbA1c 63.0 ± 16.0 mmol/mol [7.9% ± 1.5%]) and without type 1 diabetes (control), matched for sex, age, BMI and level of physical activity, were recruited (n = 12/group) to undergo vastus lateralis muscle microbiopsies. Mitochondrial respiration (high-resolution respirometry), site-specific mitochondrial H2O2 emission and Ca2+ retention capacity (CRC) (spectrofluorometry) were assessed using permeabilised myofibre bundles. Electron microscopy and tomography were used to quantify mitochondrial content and investigate muscle ultrastructure. Skeletal muscle microvasculature was assessed by immunofluorescence. RESULTS Mitochondrial oxidative capacity was significantly lower in participants with type 1 diabetes vs the control group, specifically at Complex II of the electron transport chain, without differences in mitochondrial content between groups. Muscles of those with type 1 diabetes also exhibited increased mitochondrial H2O2 emission at Complex III and decreased CRC relative to control individuals. Electron tomography revealed an increase in the size and number of autophagic remnants in the muscles of participants with type 1 diabetes. Despite this, levels of the autophagic regulatory protein, phosphorylated AMP-activated protein kinase (p-AMPKαThr172), and its downstream targets, phosphorylated Unc-51 like autophagy activating kinase 1 (p-ULK1Ser555) and p62, was similar between groups. In addition, no differences in muscle capillary density or platelet aggregation were observed between the groups. CONCLUSIONS/INTERPRETATION Alterations in mitochondrial ultrastructure and bioenergetics are evident within the skeletal muscle of active young adults with type 1 diabetes. It is yet to be elucidated whether more rigorous exercise may help to prevent skeletal muscle metabolic deficiencies in both active and inactive individuals with type 1 diabetes.
Collapse
Affiliation(s)
- Cynthia M F Monaco
- Department of Pathology and Molecular Medicine, McMaster University, 4N65 Health Sciences Centre, 1200 Main Street West, Hamilton, ON, L8N 3Z5, Canada
| | - Meghan C Hughes
- School of Kinesiology and Health Sciences, Muscle Health Research Centre, York University, Toronto, ON, Canada
| | - Sofhia V Ramos
- School of Kinesiology and Health Sciences, Muscle Health Research Centre, York University, Toronto, ON, Canada
| | - Nina E Varah
- Department of Pathology and Molecular Medicine, McMaster University, 4N65 Health Sciences Centre, 1200 Main Street West, Hamilton, ON, L8N 3Z5, Canada
| | | | - Fasih A Rahman
- Department of Kinesiology, University of Windsor, Windsor, ON, Canada
| | - Chris McGlory
- Department of Kinesiology, McMaster University, Hamilton, ON, Canada
| | | | - Matthew P Krause
- Department of Kinesiology, University of Windsor, Windsor, ON, Canada
| | - Robert Laham
- School of Kinesiology and Health Sciences, Muscle Health Research Centre, York University, Toronto, ON, Canada
| | - Thomas J Hawke
- Department of Pathology and Molecular Medicine, McMaster University, 4N65 Health Sciences Centre, 1200 Main Street West, Hamilton, ON, L8N 3Z5, Canada.
| | - Christopher G R Perry
- School of Kinesiology and Health Sciences, Muscle Health Research Centre, York University, Toronto, ON, Canada
| |
Collapse
|
21
|
Edgett BA, Hughes MC, Matusiak JBL, Perry CGR, Simpson CA, Gurd BJ. SIRT3 gene expression but not SIRT3 subcellular localization is altered in response to fasting and exercise in human skeletal muscle. Exp Physiol 2018; 101:1101-13. [PMID: 27337034 DOI: 10.1113/ep085744] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2016] [Accepted: 05/25/2016] [Indexed: 12/30/2022]
Abstract
NEW FINDINGS What is the central question of this study? Evidence from cellular and animal models suggests that SIRT3 is involved in regulating aerobic ATP production. Thus, we investigated whether changes in fatty acid and oxidative metabolism known to accompany fasting and exercise occur in association with changes in SIRT3 mitochondrial localization and expression in human skeletal muscle. What is the main finding and its importance? We find that 48 h of fasting and acute endurance exercise decrease SIRT3 mRNA expression but do not alter SIRT3 mitochondrial localization despite marked increases in fatty acid oxidation. This suggests that SIRT3 activity is not regulated by changes in mitochondrial localization in response to cellular energy stress in human skeletal muscle. The present study examined SIRT3 expression and SIRT3 mitochondrial localization in response to acute exercise and short-term fasting in human skeletal muscle. Experiment 1 involved eight healthy men (age, 21.4 ± 2.8 years; peak O2 uptake, 47.1 ± 11.8 ml min(-1) kg(-1) ) who performed a single bout of exercise at ∼55% of peak aerobic work rate for 1 h. Muscle biopsies were obtained at rest (Rest), immediately after exercise (EX-0) and 3 h postexercise (EX-3). Experiment 2 involved 10 healthy men (age, 22.0 ± 1.5 years; peak O2 uptake, 46.9 ± 6.0 ml min−1 kg−1) who underwent a 48 h fast, with muscle biopsies collected 1 h postprandial (Fed) and after 48 h of fasting (Fast). Mitochondrial respiration was measured using high-resolution respirometry in permeabilized muscle fibre bundles to assess substrate oxidation. Whole body fat oxidation increased after both exercise (Rest, 0.96 ± 0.32 kcal min(-1) ; Exercise, 5.66 ± 1.97 kcal min(-1) ; P < 0.001) and fasting (Fed, 0.87 ± 0.51 kcal min(-1) ; Fast, 1.30 ± 0.37 kcal min(-1) , P < 0.05). SIRT3 gene expression decreased (P < 0.05) after both exercise (-8%) and fasting (-19%); however, SIRT3 whole muscle protein content was unaltered after fasting. No changes were observed in SIRT3 mitochondrial localization following either exercise or fasting. Fasting also decreased the Vmax of glutamate [80 ± 43 versus 50 ± 21 pmol s(-1) (mg dry weight)(-1) ; P < 0.05]. These findings suggest that SIRT3 does not appear to be regulated by changes in mitochondrial localization at the time points measured in the present study in response to cellular energy stress in human skeletal muscle.
Collapse
Affiliation(s)
- Brittany A Edgett
- School of Kinesiology and Health Studies, Queen's University, Kingston, Ontario, Canada, K7L 3N6
| | - Meghan C Hughes
- School of Kinesiology and Health Science, Muscle Health Research Centre, York University, Toronto, Ontario, Canada, M3J 1P3
| | - Jennifer B L Matusiak
- School of Kinesiology and Health Studies, Queen's University, Kingston, Ontario, Canada, K7L 3N6
| | - Christopher G R Perry
- School of Kinesiology and Health Science, Muscle Health Research Centre, York University, Toronto, Ontario, Canada, M3J 1P3
| | - Craig A Simpson
- Department of Emergency Medicine, Queen's University, Kingston, Ontario, Canada, K7L 3N6
| | - Brendon J Gurd
- School of Kinesiology and Health Studies, Queen's University, Kingston, Ontario, Canada, K7L 3N6
| |
Collapse
|
22
|
Bhattacharya D, Ydfors M, Hughes MC, Norrbom J, Perry CGR, Scimè A. Decreased transcriptional corepressor p107 is associated with exercise-induced mitochondrial biogenesis in human skeletal muscle. Physiol Rep 2017; 5:5/5/e13155. [PMID: 28270591 PMCID: PMC5350169 DOI: 10.14814/phy2.13155] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2016] [Revised: 01/10/2017] [Accepted: 01/13/2017] [Indexed: 11/24/2022] Open
Abstract
Increased mitochondrial content is a hallmark of exercise-induced skeletal muscle remodeling. For this process, considerable evidence underscores the involvement of transcriptional coactivators in mediating mitochondrial biogenesis. However, our knowledge regarding the role of transcriptional corepressors is lacking. In this study, we assessed the association of the transcriptional corepressor Rb family proteins, Rb and p107, with endurance exercise-induced mitochondrial adaptation in human skeletal muscle. We showed that p107, but not Rb, protein levels decrease by 3 weeks of high-intensity interval training. This is associated with significant inverse association between p107 and exercise-induced improved mitochondrial oxidative phosphorylation. Indeed, p107 showed significant reciprocal correlations with the protein contents of representative markers of mitochondrial electron transport chain complexes. These findings in human skeletal muscle suggest that attenuated transcriptional repression through p107 may be a novel mechanism by which exercise stimulates mitochondrial biogenesis following exercise.
Collapse
Affiliation(s)
- Debasmita Bhattacharya
- Stem Cell Research Group, Molecular, Cellular and Integrative Physiology, Faculty of Health York University, Toronto, Canada.,Molecular, Cellular and Integrative Physiology, Faculty of Health York University, Toronto, Canada
| | - Mia Ydfors
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - Meghan C Hughes
- Molecular, Cellular and Integrative Physiology, Faculty of Health York University, Toronto, Canada
| | - Jessica Norrbom
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - Christopher G R Perry
- Molecular, Cellular and Integrative Physiology, Faculty of Health York University, Toronto, Canada
| | - Anthony Scimè
- Stem Cell Research Group, Molecular, Cellular and Integrative Physiology, Faculty of Health York University, Toronto, Canada .,Molecular, Cellular and Integrative Physiology, Faculty of Health York University, Toronto, Canada
| |
Collapse
|
23
|
Pinho RA, Sepa-Kishi DM, Bikopoulos G, Wu MV, Uthayakumar A, Mohasses A, Hughes MC, Perry CGR, Ceddia RB. High-fat diet induces skeletal muscle oxidative stress in a fiber type-dependent manner in rats. Free Radic Biol Med 2017; 110:381-389. [PMID: 28690197 DOI: 10.1016/j.freeradbiomed.2017.07.005] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/14/2017] [Revised: 05/15/2017] [Accepted: 07/05/2017] [Indexed: 02/02/2023]
Abstract
This study investigated the effects of high-fat (HF) diet on parameters of oxidative stress among muscles with distinct fiber type composition and oxidative capacities. To accomplish that, male Wistar rats were fed either a low-fat standard chow (SC) or a HF diet for 8 weeks. Soleus, extensor digitorum longus (EDL), and epitrochlearis muscles were collected and mitochondrial H2O2 (mtH2O2) emission, palmitate oxidation, and gene expression and antioxidant system were measured. Chronic HF feeding enhanced fat oxidation in oxidative and glycolytic muscles. It also caused a significant reduction in mtH2O2 emission in the EDL muscle, although a tendency towards a reduction was also found in the soleus and epitrochlearis muscles. In the epitrochlearis, HF diet increased mRNA expression of the NADPH oxidase complex; however, this muscle also showed an increase in the expression of antioxidant proteins, suggesting a higher capacity to generate and buffer ROS. The soleus muscle, despite being highly oxidative, elicited H2O2 emission rates equivalent to only 20% and 35% of the values obtained for EDL and epitrochlearis muscles, respectively. Furthermore, the Epi muscle with the lowest oxidative capacity was the second highest in H2O2 emission. In conclusion, it appears that intrinsic differences related to the distribution of type I and type II fibers, rather than oxidative capacity, drove the activity of the anti- and pro-oxidant systems and determine ROS production in different skeletal muscles. This also suggests that the impact of potentially deleterious effects of ROS production on skeletal muscle metabolism/function under lipotoxic conditions is fiber type-specific.
Collapse
Affiliation(s)
- Ricardo A Pinho
- Laboratory of Exercise Biochemistry and Physiology, Graduate Program in Health Sciences, Health Sciences Unit, Universidade do Extremo Sul Catarinense, Criciúma (UNESC), Santa Catarina, Brazil.
| | - Diane M Sepa-Kishi
- School of Kinesiology and Health Science - Muscle Health Research Centre, York University, Toronto, Ontario, Canada
| | - George Bikopoulos
- School of Kinesiology and Health Science - Muscle Health Research Centre, York University, Toronto, Ontario, Canada
| | - Michelle V Wu
- School of Kinesiology and Health Science - Muscle Health Research Centre, York University, Toronto, Ontario, Canada
| | - Abinas Uthayakumar
- School of Kinesiology and Health Science - Muscle Health Research Centre, York University, Toronto, Ontario, Canada
| | - Arta Mohasses
- School of Kinesiology and Health Science - Muscle Health Research Centre, York University, Toronto, Ontario, Canada
| | - Meghan C Hughes
- School of Kinesiology and Health Science - Muscle Health Research Centre, York University, Toronto, Ontario, Canada
| | - Christopher G R Perry
- School of Kinesiology and Health Science - Muscle Health Research Centre, York University, Toronto, Ontario, Canada
| | - Rolando B Ceddia
- School of Kinesiology and Health Science - Muscle Health Research Centre, York University, Toronto, Ontario, Canada
| |
Collapse
|
24
|
Smith BK, Ford RJ, Desjardins EM, Green AE, Hughes MC, Houde VP, Day EA, Marcinko K, Crane JD, Mottillo EP, Perry CGR, Kemp BE, Tarnopolsky MA, Steinberg GR. Salsalate (Salicylate) Uncouples Mitochondria, Improves Glucose Homeostasis, and Reduces Liver Lipids Independent of AMPK-β1. Diabetes 2016; 65:3352-3361. [PMID: 27554471 PMCID: PMC5233442 DOI: 10.2337/db16-0564] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/02/2016] [Accepted: 08/16/2016] [Indexed: 12/17/2022]
Abstract
Salsalate is a prodrug of salicylate that lowers blood glucose in patients with type 2 diabetes (T2D) and reduces nonalcoholic fatty liver disease (NAFLD) in animal models; however, the mechanism mediating these effects is unclear. Salicylate directly activates AMPK via the β1 subunit, but whether salsalate requires AMPK-β1 to improve T2D and NAFLD has not been examined. Therefore, wild-type (WT) and AMPK-β1-knockout (AMPK-β1KO) mice were treated with a salsalate dose resulting in clinically relevant serum salicylate concentrations (∼1 mmol/L). Salsalate treatment increased VO2, lowered fasting glucose, improved glucose tolerance, and led to an ∼55% reduction in liver lipid content. These effects were observed in both WT and AMPK-β1KO mice. To explain these AMPK-independent effects, we found that salicylate increases oligomycin-insensitive respiration (state 4o) and directly increases mitochondrial proton conductance at clinical concentrations. This uncoupling effect is tightly correlated with the suppression of de novo lipogenesis. Salicylate is also able to stimulate brown adipose tissue respiration independent of uncoupling protein 1. These data indicate that the primary mechanism by which salsalate improves glucose homeostasis and NAFLD is via salicylate-driven mitochondrial uncoupling.
Collapse
Affiliation(s)
- Brennan K Smith
- Division of Endocrinology and Metabolism, Department of Medicine, McMaster University, Hamilton, Ontario, Canada
| | - Rebecca J Ford
- Division of Endocrinology and Metabolism, Department of Medicine, McMaster University, Hamilton, Ontario, Canada
| | - Eric M Desjardins
- Division of Endocrinology and Metabolism, Department of Medicine, McMaster University, Hamilton, Ontario, Canada
| | - Alex E Green
- Division of Endocrinology and Metabolism, Department of Medicine, McMaster University, Hamilton, Ontario, Canada
| | - Meghan C Hughes
- Muscle Health Research Centre, School of Kinesiology and Health Science, York University, Toronto, Ontario, Canada
| | - Vanessa P Houde
- Division of Endocrinology and Metabolism, Department of Medicine, McMaster University, Hamilton, Ontario, Canada
| | - Emily A Day
- Division of Endocrinology and Metabolism, Department of Medicine, McMaster University, Hamilton, Ontario, Canada
| | - Katarina Marcinko
- Division of Endocrinology and Metabolism, Department of Medicine, McMaster University, Hamilton, Ontario, Canada
| | - Justin D Crane
- Division of Endocrinology and Metabolism, Department of Medicine, McMaster University, Hamilton, Ontario, Canada
| | - Emilio P Mottillo
- Division of Endocrinology and Metabolism, Department of Medicine, McMaster University, Hamilton, Ontario, Canada
| | - Christopher G R Perry
- Muscle Health Research Centre, School of Kinesiology and Health Science, York University, Toronto, Ontario, Canada
| | - Bruce E Kemp
- Protein Chemistry and Metabolism, St Vincent's Institute and Department of Medicine, University of Melbourne, Melbourne, Victoria, Australia
- Mary MacKillop Institute for Health Research, Australian Catholic University, Fitzroy, Victoria, Australia
| | - Mark A Tarnopolsky
- Department of Pediatrics, McMaster University, Hamilton, Ontario, Canada
| | - Gregory R Steinberg
- Division of Endocrinology and Metabolism, Department of Medicine, McMaster University, Hamilton, Ontario, Canada
- Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, Ontario, Canada
| |
Collapse
|
25
|
Ydfors M, Hughes MC, Laham R, Schlattner U, Norrbom J, Perry CGR. Modelling in vivo creatine/phosphocreatine in vitro reveals divergent adaptations in human muscle mitochondrial respiratory control by ADP after acute and chronic exercise. J Physiol 2016; 594:3127-40. [PMID: 26631938 DOI: 10.1113/jp271259] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2015] [Accepted: 11/19/2015] [Indexed: 01/14/2023] Open
Abstract
KEY POINTS Mitochondrial respiratory sensitivity to ADP is thought to influence muscle fitness and is partly regulated by cytosolic-mitochondrial diffusion of ADP or phosphate shuttling via creatine/phosphocreatine (Cr/PCr) through mitochondrial creatine kinase (mtCK). Previous measurements of respiration in vitro with Cr (saturate mtCK) or without (ADP/ATP diffusion) show mixed responses of ADP sensitivity following acute exercise vs. less sensitivity after chronic exercise. In human muscle, modelling in vivo 'exercising' [Cr:PCr] during in vitro assessments revealed novel responses to exercise that differ from detections with or without Cr (±Cr). Acute exercise increased ADP sensitivity when measured without Cr but had no effect ±Cr or with +Cr:PCr, whereas chronic exercise increased sensitivity ±Cr but lowered sensitivity with +Cr:PCr despite increased markers of mitochondrial oxidative capacity. Controlling in vivo conditions during in vitro respiratory assessments reveals responses to exercise that differ from typical ±Cr comparisons and challenges our understanding of how exercise improves metabolic control in human muscle. ABSTRACT Mitochondrial respiratory control by ADP (Kmapp ) is viewed as a critical regulator of muscle energy homeostasis. However, acute exercise increases, decreases or has no effect on Kmapp in human muscle, whereas chronic exercise surprisingly decreases sensitivity despite greater mitochondrial content. We hypothesized that modelling in vivo mitochondrial creatine kinase (mtCK)-dependent phosphate-shuttling conditions in vitro would reveal increased sensitivity (lower Kmapp ) after acute and chronic exercise. The Kmapp was determined in vitro with 20 mm Cr (+Cr), 0 mm Cr (-Cr) or 'in vivo exercising' 20 mm Cr/2.4 mm PCr (Cr:PCr) on vastus lateralis biopsies sampled from 11 men before, immediately after and 3 h after exercise on the first, fifth and ninth sessions over 3 weeks. Dynamic responses to acute exercise occurred throughout training, whereby the first session did not change Kmapp with in vivo Cr:PCr despite increases in -Cr. The fifth session decreased sensitivity with Cr:PCr or +Cr despite no change in -Cr. Chronic exercise increased sensitivity ±Cr in association with increased electron transport chain content (+33-62% complexes I-V), supporting classic proposals that link increased sensitivity to oxidative capacity. However, in vivo Cr:PCr reveals a perplexing decreased sensitivity, contrasting the increases seen ±Cr. Functional responses occurred without changes in fibre type or proteins regulating mitochondrial-cytosolic energy exchange (mtCK, VDAC and ANT). Despite the dynamic responses seen with ±Cr, modelling in vivo phosphate-shuttling conditions in vitro reveals that ADP sensitivity is unchanged after high-intensity exercise and is decreased after training. These findings challenge our understanding of how exercise regulates skeletal muscle energy homeostasis.
Collapse
Affiliation(s)
- Mia Ydfors
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - Meghan C Hughes
- School of Kinesiology and Health Science, York University, Toronto, ON, Canada.,Muscle Health Research Centre, York University, Toronto, ON, Canada
| | - Robert Laham
- Muscle Health Research Centre, York University, Toronto, ON, Canada
| | - Uwe Schlattner
- Laboratory of Fundamental and Applied Bioenergetics (LBFA) and SFR Environmental and Systems Biology (BEeSy), University Grenoble Alpes, Grenoble, France
| | - Jessica Norrbom
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - Christopher G R Perry
- School of Kinesiology and Health Science, York University, Toronto, ON, Canada.,Muscle Health Research Centre, York University, Toronto, ON, Canada
| |
Collapse
|
26
|
Hughes MC, Ramos SV, Turnbull PC, Nejatbakhsh A, Baechler BL, Tahmasebi H, Laham R, Gurd BJ, Quadrilatero J, Kane DA, Perry CGR. Mitochondrial Bioenergetics and Fiber Type Assessments in Microbiopsy vs. Bergstrom Percutaneous Sampling of Human Skeletal Muscle. Front Physiol 2015; 6:360. [PMID: 26733870 PMCID: PMC4683189 DOI: 10.3389/fphys.2015.00360] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [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: 09/11/2015] [Accepted: 11/16/2015] [Indexed: 01/22/2023] Open
Abstract
Microbiopsies of human skeletal muscle are increasingly adopted by physiologists for a variety of experimental assays given the reduced invasiveness of this procedure compared to the classic Bergstrom percutaneous biopsy technique. However, a recent report demonstrated lower mitochondrial respiration in saponin-permeabilized muscle fiber bundles (PmFB) prepared from microbiopsies vs. Bergstrom biopsies. We hypothesized that ADP-induced contraction (rigor) of smaller length microbiopsy PmFB causes a greater reduction in maximal respiration vs. Bergstrom, such that respiration could be increased by a myosin II ATPase-inhibitor (Blebbistatin; BLEB). Eleven males and females each received a 2 mm diameter percutaneous microbiopsy and a 5 mm diameter Bergstrom percutaneous biopsy in opposite legs. Glutamate/malate (5/0.5 mM)—supported respiration in microbiopsy PmFB was lower than Bergstrom at submaximal concentrations of ADP. 5 μM BLEB reduced this impairment such that there were no differences relative to Bergstrom ± BLEB. Surprisingly, pyruvate (5 mM)-supported respiration was not different between either biopsy technique ±BLEB, whereas BLEB increased succinate-supported respiration in Bergstrom only. H2O2 emission was lower in microbiopsy PmFB compared to Bergstrom PmFB in the presence of BLEB. Microbiopsies contained fewer type I fibers (37 vs. 47%) and more type IIX fibers (20 vs. 8%) compared to Bergstrom possibly due to sampling site depth and/or longitudinal location. These findings suggest that smaller diameter percutaneous biopsies yield lower glutamate-supported mitochondrial respiratory kinetics which is increased by preventing ADP-induced rigor with myosin inhibition. Microbiopsies of human skeletal muscle can be utilized for assessing mitochondrial respiratory kinetics in PmFB when assay conditions are supplemented with BLEB, but fiber type differences with this method should be considered.
Collapse
Affiliation(s)
- Meghan C Hughes
- Muscle Health Research Centre, School of Kinesiology and Health Science, York University Toronto, ON, Canada
| | - Sofhia V Ramos
- Muscle Health Research Centre, School of Kinesiology and Health Science, York University Toronto, ON, Canada
| | - Patrick C Turnbull
- Muscle Health Research Centre, School of Kinesiology and Health Science, York University Toronto, ON, Canada
| | - Ali Nejatbakhsh
- Muscle Health Research Centre, School of Kinesiology and Health Science, York University Toronto, ON, Canada
| | | | - Houman Tahmasebi
- Muscle Health Research Centre, School of Kinesiology and Health Science, York University Toronto, ON, Canada
| | - Robert Laham
- Muscle Health Research Centre, School of Kinesiology and Health Science, York University Toronto, ON, Canada
| | - Brendon J Gurd
- School of Kinesiology and Health Studies, Queen's University Kingston, ON, Canada
| | - Joe Quadrilatero
- Department of Kinesiology, University of Waterloo Waterloo, ON, Canada
| | - Daniel A Kane
- Department of Human Kinetics, St. Francis Xavier University Antigonish, NS, Canada
| | - Christopher G R Perry
- Muscle Health Research Centre, School of Kinesiology and Health Science, York University Toronto, ON, Canada
| |
Collapse
|
27
|
Williams CB, Hughes MC, Edgett BA, Scribbans TD, Simpson CA, Perry CGR, Gurd BJ. An examination of resveratrol's mechanisms of action in human tissue: impact of a single dose in vivo and dose responses in skeletal muscle ex vivo. PLoS One 2014; 9:e102406. [PMID: 25019209 PMCID: PMC4096915 DOI: 10.1371/journal.pone.0102406] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [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: 01/26/2014] [Accepted: 06/18/2014] [Indexed: 01/02/2023] Open
Abstract
The current study tested the hypothesis that a single, moderate dose of RSV would activate the AMPK/SIRT1 axis in human skeletal muscle and adipose tissue. Additionally, the effects of RSV on mitochondrial respiration in PmFBs were examined. Eight sedentary men (23.8±2.4 yrs; BMI: 32.7±7.1) reported to the lab on two occasions where they were provided a meal supplemented with 300 mg of RSV or a placebo. Blood samples, and a muscle biopsy were obtained in the fasted state and again, with the addition of an adipose tissue biopsy, two hours post-prandial. The effect of RSV on mitochondrial respiration was examined in PmFBs taken from muscle biopsies from an additional eight men (23.4±5.4 yrs; BMI: 24.4±2.8). No effect of RSV was observed on nuclear SIRT1 activity, acetylation of p53, or phosphorylation of AMPK, ACC or PKA in either skeletal muscle or adipose tissue. A decrease in post absorptive insulin levels was accompanied by elevated skeletal muscle phosphorylation of p38 MAPK, but no change in either skeletal muscle or adipose tissue insulin signalling. Mitochondrial respiration in PmFBs was rapidly inhibited by RSV at 100–300 uM depending on the substrate examined. These results question the efficacy of a single dose of RSV at altering skeletal muscle and adipose tissue AMPK/SIRT1 activity in humans and suggest that RSV mechanisms of action in humans may be associated with altered cellular energetics resulting from impaired mitochondrial ATP production.
Collapse
Affiliation(s)
- Cameron B. Williams
- School of Kinesiology and Health Studies, Queen's University, Kingston, Ontario, Canada
| | - Meghan C. Hughes
- School of Kinesiology and Health Science, York University, Toronto, Ontario, Canada
| | - Brittany A. Edgett
- School of Kinesiology and Health Studies, Queen's University, Kingston, Ontario, Canada
| | - Trisha D. Scribbans
- School of Kinesiology and Health Studies, Queen's University, Kingston, Ontario, Canada
| | - Craig A. Simpson
- Department of Emergency Medicine, Queen's University, Kingston, Ontario, Canada
| | | | - Brendon J. Gurd
- School of Kinesiology and Health Studies, Queen's University, Kingston, Ontario, Canada
- * E-mail:
| |
Collapse
|
28
|
Kane DA, White AE, Elustondo P, Hughes MC, Brebner K, Pavlov E. Physical and functional association of lactate dehydrogenase with mitochondria in intact and permeabilized skeletal muscle fibers. FASEB J 2013. [DOI: 10.1096/fasebj.27.1_supplement.lb765] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Daniel A. Kane
- Human KineticsSt. Francis Xavier UniversityAntigonishNSCanada
| | | | - Pia Elustondo
- Physiology & BiophysicsDalhousie UniversityHalifaxNSCanada
| | | | - Karen Brebner
- PsychologySt. Francis Xavier UniversityAntigonishNSCanada
| | - Evgeny Pavlov
- Physiology & BiophysicsDalhousie UniversityHalifaxNSCanada
| |
Collapse
|
29
|
Webb PM, Ibiebele TI, Hughes MC, Beesley J, van der Pols JC, Chen X, Nagle CM, Bain CJ, Chenevix-Trench G. Folate and related micronutrients, folate-metabolising genes and risk of ovarian cancer. Eur J Clin Nutr 2011; 65:1133-40. [PMID: 21629268 DOI: 10.1038/ejcn.2011.99] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
BACKGROUND/OBJECTIVE Folates are essential for DNA synthesis and methylation, and thus may have a role in carcinogenesis. Limited evidence suggests folate-containing foods might protect against some cancers and may partially mitigate the increased risk of breast cancer associated with alcohol intake, but there is little information regarding ovarian cancer. Our aim was to evaluate the role of folate and related micronutrients, polymorphisms in key folate-metabolising genes and environmental factors in ovarian carcinogenesis. SUBJECTS/METHODS Participants in the Australian Ovarian Cancer Study (1363 cases, 1414 controls) self-completed risk factor and food-frequency questionnaires. DNA samples (1638 cases, 1278 controls) were genotyped for 49 tag single-nucleotide polymorphisms (SNPs) in the methylene tetrahydrofolate reductase (MTHFR), methionine synthase (MTR) and MTR reductase (MTRR) genes. Logistic regression models were used to generate adjusted odds ratios and 95% confidence intervals. RESULTS We saw no overall association between the intake of folate, B vitamins or other methyl donors and ovarian cancer risk, although increasing folate from foods was associated with reduced risk among current smokers (P(trend)=0.03) and folic acid intake was associated with borderline significant increased risks among women who consumed ≥1 standard alcoholic drinks/day (odds ratio (OR)=1.64; 95% confidence interval (CI) 1.05-2.54, P(trend)=0.05). Two SNPs (rs7365052, rs7526063) showed borderline significant inverse associations with ovarian cancer risk; both had very low minor allele frequencies. There was little evidence for interaction between genotype and micronutrient intake or for variation between different histological subtypes of ovarian cancer. CONCLUSIONS Our data provide little evidence to support a protective role for folate in ovarian carcinogenesis but suggest further evaluation of the joint effects of folic acid and alcohol is warranted.
Collapse
Affiliation(s)
- P M Webb
- Gynaecological Cancers Group, Queensland Institute of Medical Research, Herston, Brisbane, Australia.
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
30
|
Abstract
Due to the growing knowledge about the role of specific fatty acids in health and disease, dietary intake measurements of individual fatty acids or classes of fatty acids are becoming increasingly important. The objective of this study was to evaluate the ability of the Nambour FFQ to estimate intakes of specific fatty acids, particularly PUFA. The study population was a sub-sample of adult participants in a randomised controlled trial of beta-carotene and sunscreen in the prevention of skin cancer (n 43). Dietary intake was assessed by a self-administered FFQ and a weighed food record (WFR). Non-fasting blood samples were collected and analysed for plasma phospholipid fatty acids. Median intakes on the FFQ were generally higher than the WFR except for the n-3 PUFA groups, where the FFQ estimated higher intakes. Correlations between the FFQ and WFR were moderate (r 0 x 32-0 x 59) except for trans fatty acids (r 0 x 03). Correlations between each of the dietary assessment methods and the plasma phospholipids were poor for all fatty acids other than the PUFA. Using the methods of triads approach, the FFQ validity coefficients for total n-3 fatty acids, total long chain n-3 fatty acids, EPA, arachidonic acid, docosapentaenoic acid and DHA were 0 x 50, 0 x 63, 0 x 45 and 0 x 62 and 0 x 62, respectively. For most fatty acids, the FFQ adequately estimates group mean fatty acid intakes and can adequately rank individuals; however, the ability of this FFQ to estimate trans fatty acids was poor.
Collapse
Affiliation(s)
- S A McNaughton
- School of Population Health, University of Queensland, Herston, Australia.
| | | | | |
Collapse
|
31
|
Abstract
OBJECTIVE To investigate the association between total alcohol intake and intake of different types of alcoholic beverages in relation to the risk of basal cell (BCC) and squamous cell (SCC) carcinoma of the skin. DESIGN Prospective cohort study. SETTING Follow-up data from a community-based skin cancer study in Australia. SUBJECTS Randomly selected sample of 1360 adult residents of the township of Nambour who completed a food frequency questionnaire in 1992 and were monitored for BCC and SCC until 31 December 2002. RESULTS No significant association was found between overall BCC or SCC risk and total alcohol intake, or intake of beer, white wine, red wine or sherry and port. However, among those with a prior skin cancer history, there was a significant doubling of risk of SCC for above-median consumption of sherry and port (multivariable adjusted relative risk 2.46, 95% confidence interval 1.06-5.72) compared with abstainers. CONCLUSIONS There are no associations between first occurrence of skin cancers and alcoholic beverage consumption. People with a history of skin cancer who consume above-average quantities of sherry or port may be at a raised risk of SCC, although replication of these findings in different study populations is needed to confirm this possible role of specific alcoholic beverages in secondary keratinocytic skin cancer risk.
Collapse
Affiliation(s)
- T M R Ansems
- Cancer and Population Studies Group, Queensland Institute of Medical Research, Queensland, Australia
| | | | | | | | | | | |
Collapse
|
32
|
Hughes RG, Sharp DS, Hughes MC, Akau'ola S, Heinsbroek P, Velayudhan R, Schulz D, Palmer K, Cavalli-Sforza T, Galea G. Environmental influences on helminthiasis and nutritional status among Pacific schoolchildren. Int J Environ Health Res 2004; 14:163-177. [PMID: 15203448 DOI: 10.1080/0960312042000218589] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
This paper describes a study undertaken to: (1) determine the prevalence of Ascaris lumbricoides, Trichuris trichiura and hookworm infections and nutritional status among Pacific Island school children; (2) identify factors influencing helminthiasis; (3) identify interventions to improve school health. A total of 3,683 children aged 5-12 years attending 27 primary schools in 13 Pacific Island countries were surveyed along with school environmental data. Stool samples were collected from 1996 children (54.2%) and analysed for ova and helminths. Total prevalence of helminthiasis was 32.8%. Anaemia prevalence was 12.4%. Children with helminthiasis and anaemia were found to be 8.7 times more likely to be stunted and 4.3 times more likely to be underweight than non-anaemic and non-infected children. Four significant environmental influences on helminthiasis were identified: (1) an inadequate water supply; (2); availability of a school canteen; (3) regular water/sanitation maintenance regimes; and (4) overcrowded classrooms. Helminthiasis was found to be strongly associated with anaemia, stunting and underweight and environmental influences identified. Although mass anti-helminthic drug administrations (MDA) have been taking place, reinfection is common as drug therapy alone is not enough. Programme effectiveness depends upon upgrading school environments to include an adequate water supply, controlled food preparation/provision, well-maintained water/sanitation facilities and class sizes of 30 students or less.
Collapse
Affiliation(s)
- R G Hughes
- Nutrition Program, Australian Centre for International & Tropical Health & Nutrition, University of Queensland, Brisbane, Australia.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
33
|
Clemens NA, Bebchuk W, Beitman BD, Blinder BJ, Gabbard GO, Goin MK, Hughes MC, Kay J, Kimmich RA, Lazar SG, Reiss D, Szigethy EM, Tasman A. Disputing psychiatry's redefinition. Am J Psychiatry 1997; 154:1633-5. [PMID: 9356592 DOI: 10.1176/ajp.154.11.1633] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
|
34
|
Hughes MC. Critical care nursing for the patient with a spinal cord injury. Crit Care Nurs Clin North Am 1990; 2:33-40. [PMID: 2357313] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Knowledge of the dynamics of spinal cord injury to anticipate the myriad of physiologic and psychological complications is essential for effective interventions to achieve optimal patient outcomes. Continuous expert nursing care must be provided to ensure that the patient survives life-threatening events and to facilitate optimal adaptation of the patient and family during this enormous emotional upheaval of their lives. Given the devastating effects of a spinal cord injury, the critical care nurse faces one of the most complex and potentially rewarding challenges of his or her career.
Collapse
|
35
|
|
36
|
Hughes MC, Goldman BL, Snyder NF. Hyperactivity and the attention deficit disorder. Am Fam Physician 1983; 27:119-26. [PMID: 6858813] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
The attention deficit disorder is a clinical syndrome manifested by inattention, impulsivity and hyperactivity beginning before age seven and persisting for at least six months. The family physician plays a key role in consolidating the observations of parents and teachers with the findings on medical evaluation. The physician also initiates the comprehensive treatment program with counseling and stimulant medication, and coordinates the use of special education, mental health and other resources as needed.
Collapse
|
37
|
Abstract
Children hospitalized with psychogenic abdominal pain and the children's families are discussed from the perspective of a child psychiatrist working within the pediatric hospital. Psychosocial and emotional difficulties for the child and parents are noted as families use somatic symptoms to deal with psychic distress. Principles for management are emphasized, utilizing a comprehensive team approach by physicians, nurses, and other health professionals. Through constructive use of hospitalization and informed follow-up, these children and their parents can be helped toward symptomatic improvement and a more meaningful understanding and resolution of their underlying emotional difficulties.
Collapse
|
38
|
|