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Sahu Y, Jamadade P, Ch Maharana K, Singh S. Role of mitochondrial homeostasis in D-galactose-induced cardiovascular ageing from bench to bedside. Mitochondrion 2024; 78:101923. [PMID: 38925493 DOI: 10.1016/j.mito.2024.101923] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2024] [Revised: 06/11/2024] [Accepted: 06/15/2024] [Indexed: 06/28/2024]
Abstract
Ageing is an inevitable phenomenon which affects the cellular to the organism level in the progression of the time. Oxidative stress and inflammation are now widely regarded as the key processes involved in the aging process, which may then cause significant harm to mitochondrial DNA, leading to apoptosis. Normal circulatory function is a significant predictor of disease-free life expectancy. Indeed, disorders affecting the cardiovascular system, which are becoming more common, are the primary cause of worldwide morbidity, disability, and mortality. Cardiovascular aging may precede or possibly underpin overall, age-related health decline. Numerous studies have foundmitochondrial mechanistc approachplays a vital role in the in the onset and development of aging. The D-galactose (D-gal)-induced aging model is well recognized and commonly used in the aging study. In this review we redeposit the association of the previous and current studies on mitochondrial homeostasis and its underlying mechanisms in D-galactose cardiovascular ageing. Further we focus the novel and the treatment strategies to combat the major complication leading to the cardiovascular ageing.
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Affiliation(s)
- Yogita Sahu
- Department of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research (NIPER)-Hajipur, Vaishali, Bihar, India
| | - Pratiksha Jamadade
- Department of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research (NIPER)-Hajipur, Vaishali, Bihar, India
| | - Krushna Ch Maharana
- Department of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research (NIPER)-Hajipur, Vaishali, Bihar, India
| | - Sanjiv Singh
- Department of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research (NIPER)-Hajipur, Vaishali, Bihar, India.
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Zhang T, Yi Q, Huang W, Feng J, Liu H. New insights into the roles of Irisin in diabetic cardiomyopathy and vascular diseases. Biomed Pharmacother 2024; 175:116631. [PMID: 38663105 DOI: 10.1016/j.biopha.2024.116631] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2024] [Revised: 04/11/2024] [Accepted: 04/17/2024] [Indexed: 06/03/2024] Open
Abstract
Diabetes mellitus (DM) is a prevalent chronic disease in the 21st century due to increased lifespan and unhealthy lifestyle choices. Extensive research indicates that exercise can play a significant role in regulating systemic metabolism by improving energy metabolism and mitigating various metabolic disorders, including DM. Irisin, a well-known exerkine, was initially reported to enhance energy expenditure by indicating the browning of white adipose tissue (WAT) through peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α) signaling. In this review, we summarize the potential mechanisms underlying the beneficial effects of Irisin on glucose dysmetabolism, including reducing gluconeogenesis, enhancing insulin energy expenditure, and promoting glycogenesis. Additionally, we highlight Irisin's potential to improve diabetic vascular diseases by stimulating nitric oxide (NO) production, reducing oxidative and nitrosative stress, curbing inflammation, and attenuating endothelial cell aging. Furthermore, we discuss the potential of Irisin to improve diabetic cardiomyopathy by preventing cardiomyocyte loss and reducing myocardial hypertrophy and fibrosis. Given Irisin's promising functions in managing diabetic cardiomyopathy and vascular diseases, targeting Irisin for therapeutic purposes could be a fruitful avenue for future research and clinical interventions.
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Affiliation(s)
- Tiandong Zhang
- Collage of Integration of Traditional Chinese and Western Medicine, Southwest Medical University, Luzhou, Sichuan 646000, China
| | - Qian Yi
- Department of Physiology, School of Basic Medical Science, Southwest Medical University, Luzhou, Sichuan 646000, China
| | - Wenhua Huang
- Collage of Integration of Traditional Chinese and Western Medicine, Southwest Medical University, Luzhou, Sichuan 646000, China; Guangdong Engineering Research Center for Translation of Medical 3D Printing Application, Guangdong Provincial Key Laboratory of Digital Medicine and Biomechanics, National Key Discipline of Human Anatomy, School of Basic Medical Sciences, Southern Medical University, Guangzhou 510515, China.
| | - Jianguo Feng
- Anesthesiology and Critical Care Medicine Key Laboratory of Luzhou, The Affiliated Hospital, Southwest Medical University, Luzhou, Sichuan Province 646000, China.
| | - Huan Liu
- Department of Orthopedics, The Affiliated Traditional Chinese Medicine Hospital, Southwest Medical University, Luzhou, Sichuan 646000, China; The Third People's Hospital of Longmatan District, Luzhou, Sichuan 646000, China.
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Liu B, Xie D, Huang X, Jin S, Dai Y, Sun X, Li D, Bennett AM, Diano S, Huang Y. Skeletal muscle TET3 promotes insulin resistance through destabilisation of PGC-1α. Diabetologia 2024; 67:724-737. [PMID: 38216792 PMCID: PMC10904493 DOI: 10.1007/s00125-023-06073-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/29/2023] [Accepted: 11/17/2023] [Indexed: 01/14/2024]
Abstract
AIM/HYPOTHESIS The peroxisome proliferator-activated receptor-γ coactivator α (PGC-1α) plays a critical role in the maintenance of glucose, lipid and energy homeostasis by orchestrating metabolic programs in multiple tissues in response to environmental cues. In skeletal muscles, PGC-1α dysregulation has been associated with insulin resistance and type 2 diabetes but the underlying mechanisms have remained elusive. This research aims to understand the role of TET3, a member of the ten-eleven translocation (TET) family dioxygenases, in PGC-1α dysregulation in skeletal muscles in obesity and diabetes. METHODS TET expression levels in skeletal muscles were analysed in humans with or without type 2 diabetes, as well as in mouse models of high-fat diet (HFD)-induced or genetically induced (ob/ob) obesity/diabetes. Muscle-specific Tet3 knockout (mKD) mice were generated to study TET3's role in muscle insulin sensitivity. Genome-wide expression profiling (RNA-seq) of muscle tissues from wild-type (WT) and mKD mice was performed to mine deeper insights into TET3-mediated regulation of muscle insulin sensitivity. The correlation between PGC-1α and TET3 expression levels was investigated using muscle tissues and in vitro-derived myotubes. PGC-1α phosphorylation and degradation were analysed using in vitro assays. RESULTS TET3 expression was elevated in skeletal muscles of humans with type 2 diabetes and in HFD-fed and ob/ob mice compared with healthy controls. mKD mice exhibited enhanced glucose tolerance, insulin sensitivity and resilience to HFD-induced insulin resistance. Pathway analysis of RNA-seq identified 'Mitochondrial Function' and 'PPARα Pathway' to be among the top biological processes regulated by TET3. We observed higher PGC-1α levels (~25%) in muscles of mKD mice vs WT mice, and lower PGC-1α protein levels (~25-60%) in HFD-fed or ob/ob mice compared with their control counterparts. In human and murine myotubes, increased PGC-1α levels following TET3 knockdown contributed to improved mitochondrial respiration and insulin sensitivity. TET3 formed a complex with PGC-1α and interfered with its phosphorylation, leading to its destabilisation. CONCLUSIONS/INTERPRETATION Our results demonstrate an essential role for TET3 in the regulation of skeletal muscle insulin sensitivity and suggest that TET3 may be used as a potential therapeutic target for the metabolic syndrome. DATA AVAILABILITY Sequences are available from the Gene Expression Omnibus ( https://www.ncbi.nlm.nih.gov/geo/ ) with accession number of GSE224042.
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Affiliation(s)
- Beibei Liu
- Department of Obstetrics, Gynecology & Reproductive Sciences, Yale University School of Medicine, New Haven, CT, USA
- Center of Reproductive Medicine, National Health Commission Key Laboratory of Advanced Reproductive Medicine and Fertility, Shengjing Hospital of China Medical University, Shenyang, China
| | - Di Xie
- Department of Obstetrics, Gynecology & Reproductive Sciences, Yale University School of Medicine, New Haven, CT, USA
- Department of Reproductive Medicine, General Hospital of Central Theater Command, Wuhan, Hubei, China
| | - Xinmei Huang
- Department of Obstetrics, Gynecology & Reproductive Sciences, Yale University School of Medicine, New Haven, CT, USA
- Department of Endocrinology, Fifth People's Hospital of Shanghai, Fudan University School of Medicine, Shanghai, China
| | - Sungho Jin
- Institute of Human Nutrition, Columbia University Irving Medical Center, New York, NY, USA
| | - Yangyang Dai
- Department of Obstetrics, Gynecology & Reproductive Sciences, Yale University School of Medicine, New Haven, CT, USA
- Assisted Reproduction Unit, Department of Obstetrics and Gynecology, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Xiaoli Sun
- Department of Obstetrics, Gynecology & Reproductive Sciences, Yale University School of Medicine, New Haven, CT, USA
- Center of Reproductive Medicine, Department of Obstetrics and Gynecology, Affiliated Hospital of Nantong University, Jiangsu, China
| | - Da Li
- Department of Obstetrics, Gynecology & Reproductive Sciences, Yale University School of Medicine, New Haven, CT, USA
- Center of Reproductive Medicine, National Health Commission Key Laboratory of Advanced Reproductive Medicine and Fertility, Shengjing Hospital of China Medical University, Shenyang, China
| | - Anton M Bennett
- Departments of Pharmacology and of Comparative Medicine, Yale University School of Medicine, New Haven, CT, USA
- Yale Center for Molecular and Systems Metabolism, Yale University School of Medicine, New Haven, CT, USA
| | - Sabrina Diano
- Institute of Human Nutrition, Columbia University Irving Medical Center, New York, NY, USA
| | - Yingqun Huang
- Department of Obstetrics, Gynecology & Reproductive Sciences, Yale University School of Medicine, New Haven, CT, USA.
- Yale Center for Molecular and Systems Metabolism, Yale University School of Medicine, New Haven, CT, USA.
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Khalil M, Shanmugam H, Abdallah H, John Britto JS, Galerati I, Gómez-Ambrosi J, Frühbeck G, Portincasa P. The Potential of the Mediterranean Diet to Improve Mitochondrial Function in Experimental Models of Obesity and Metabolic Syndrome. Nutrients 2022; 14:nu14153112. [PMID: 35956289 PMCID: PMC9370259 DOI: 10.3390/nu14153112] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2022] [Revised: 07/24/2022] [Accepted: 07/25/2022] [Indexed: 01/27/2023] Open
Abstract
The abnormal expansion of body fat paves the way for several metabolic abnormalities including overweight, obesity, and diabetes, which ultimately cluster under the umbrella of metabolic syndrome (MetS). Patients with MetS are at an increased risk of cardiovascular disease, morbidity, and mortality. The coexistence of distinct metabolic abnormalities is associated with the release of pro-inflammatory adipocytokines, as components of low-to-medium grade systemic inflammation and increased oxidative stress. Adopting healthy lifestyles, by using appropriate dietary regimens, contributes to the prevention and treatment of MetS. Metabolic abnormalities can influence the function and energetic capacity of mitochondria, as observed in many obesity-related cardio-metabolic disorders. There are preclinical studies both in cellular and animal models, as well as clinical studies, dealing with distinct nutrients of the Mediterranean diet (MD) and dysfunctional mitochondria in obesity and MetS. The term “Mitochondria nutrients” has been adopted in recent years, and it depicts the adequate nutrients to keep proper mitochondrial function. Different experimental models show that components of the MD, including polyphenols, plant-derived compounds, and polyunsaturated fatty acids, can improve mitochondrial metabolism, biogenesis, and antioxidant capacity. Such effects are valuable to counteract the mitochondrial dysfunction associated with obesity-related abnormalities and can represent the beneficial feature of polyphenols-enriched olive oil, vegetables, nuts, fish, and plant-based foods, as the main components of the MD. Thus, developing mitochondria-targeting nutrients and natural agents for MetS treatment and/or prevention is a logical strategy to decrease the burden of disease and medications at a later stage. In this comprehensive review, we discuss the effects of the MD and its bioactive components on improving mitochondrial structure and activity.
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Affiliation(s)
- Mohamad Khalil
- Clinica Medica “A. Murri”, Department of Biomedical Sciences & Human Oncology, University of Bari Medical School, Piazza Giulio Cesare 11, 70124 Bari, Italy; (M.K.); (H.S.); (H.A.); (J.S.J.B.); (I.G.)
- Department of Soil, Plant and Food Sciences, University of Bari Aldo Moro, Via Amendola 165/a, 70126 Bari, Italy
| | - Harshitha Shanmugam
- Clinica Medica “A. Murri”, Department of Biomedical Sciences & Human Oncology, University of Bari Medical School, Piazza Giulio Cesare 11, 70124 Bari, Italy; (M.K.); (H.S.); (H.A.); (J.S.J.B.); (I.G.)
| | - Hala Abdallah
- Clinica Medica “A. Murri”, Department of Biomedical Sciences & Human Oncology, University of Bari Medical School, Piazza Giulio Cesare 11, 70124 Bari, Italy; (M.K.); (H.S.); (H.A.); (J.S.J.B.); (I.G.)
| | - Jerlin Stephy John Britto
- Clinica Medica “A. Murri”, Department of Biomedical Sciences & Human Oncology, University of Bari Medical School, Piazza Giulio Cesare 11, 70124 Bari, Italy; (M.K.); (H.S.); (H.A.); (J.S.J.B.); (I.G.)
| | - Ilaria Galerati
- Clinica Medica “A. Murri”, Department of Biomedical Sciences & Human Oncology, University of Bari Medical School, Piazza Giulio Cesare 11, 70124 Bari, Italy; (M.K.); (H.S.); (H.A.); (J.S.J.B.); (I.G.)
| | - Javier Gómez-Ambrosi
- Metabolic Research Laboratory, Clínica Universidad de Navarra, 31008 Pamplona, Spain; (J.G.-A.); (G.F.)
- CIBER Fisiopatología de la Obesidad y Nutrición (CIBEROBN), ISCIII, 28029 Pamplona, Spain
- Obesity and Adipobiology Group, Instituto de Investigación Sanitaria de Navarra (IdiSNA), 31008 Pamplona, Spain
| | - Gema Frühbeck
- Metabolic Research Laboratory, Clínica Universidad de Navarra, 31008 Pamplona, Spain; (J.G.-A.); (G.F.)
- CIBER Fisiopatología de la Obesidad y Nutrición (CIBEROBN), ISCIII, 28029 Pamplona, Spain
- Obesity and Adipobiology Group, Instituto de Investigación Sanitaria de Navarra (IdiSNA), 31008 Pamplona, Spain
- Department of Endocrinology & Nutrition, Clínica Universidad de Navarra, 31008 Pamplona, Spain
| | - Piero Portincasa
- Clinica Medica “A. Murri”, Department of Biomedical Sciences & Human Oncology, University of Bari Medical School, Piazza Giulio Cesare 11, 70124 Bari, Italy; (M.K.); (H.S.); (H.A.); (J.S.J.B.); (I.G.)
- Correspondence: ; Tel.: +39-328-4687215
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Fan H, Shen Y, Ren Y, Mou Q, Lin T, Zhu L, Ren T. Combined intake of blueberry juice and probiotics ameliorate mitochondrial dysfunction by activating SIRT1 in alcoholic fatty liver disease. Nutr Metab (Lond) 2021; 18:50. [PMID: 33971886 PMCID: PMC8108333 DOI: 10.1186/s12986-021-00554-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2020] [Accepted: 02/24/2021] [Indexed: 11/10/2022] Open
Abstract
Background Mitochondrial dysfunction has been implicated as a significant factor in the liver disease process. Blueberry juice and probiotics (BP) synergistically improve liver function in alcoholic fatty liver disease (AFLD), although the mechanism for this effect was unclear. This study aims to investigate the effect and specific mechanisms of BP on AFLD. Methods C57/BL6 mice were randomly divided into seven groups: CG (control), MG (AFLD model), BJ (MG mice treated with blueberry), BJB (MG mice treated with BP), SI (AFLD mice treated with SIRT1 siRNA), BJSI (SI mice treated with blueberry), and BJBSI (SI mice treated with BP). The mice were fed an alcohol liquid diet for 10 days to establish the AFLD model, and subjected to BP and SIRT1 siRNA intervention for 10 days. Liver pathology was performed on day 11, and biochemical and molecular analyses of liver mitochondria were employed on day 12. Results BP significantly ameliorated hepatic mitochondrial injury, mitochondrial swelling, and hepatic necrosis in AFLD. BP alleviated hepatic mitochondrial dysfunction by increasing the expression of succinate dehydrogenase and cytochrome c oxidase, increasing respiratory control rate and the ADP/O ratio, and facilitating the synthesis of energy-related molecules. Besides, BP increased the expression of glutathione and superoxide dismutase, and inhibited malondialdehyde expression and reactive oxygen species activity. BP-induced sirtuin 1 (SIRT1), which activates peroxisome proliferator-activated receptor-gamma coactivator-1α, both of which mediate mitochondrial homeostasis. SIRT1 silencing suppressed the BP-induced changes in liver mitochondria, blunting its efficacy. Conclusions The ingredients of BP ameliorate hepatocyte mitochondrial dysfunction in AFLD mice. Supplementary Information The online version contains supplementary material available at 10.1186/s12986-021-00554-3.
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Affiliation(s)
- Houmin Fan
- Guizhou Medical University, Guiyang, Guizhou, China
| | - Yanyan Shen
- Tongren Maternal and Child Health Care Hospital, Tongren, Guizhou, China
| | - Ya Ren
- Guizhou Medical University, Guiyang, Guizhou, China
| | - Qiuju Mou
- Department of Blood Transfusion, The Affiliated Baiyun Hospital of Guizhou Medical University, Guiyang, Guizhou, China
| | - Tao Lin
- Department of Clinical Examination, The Affiliated Hospital of Guizhou Medical University, No 28, Guiyi Street, Yunyan District, Guiyang, Guizhou, China
| | - Lili Zhu
- Department of Blood Transfusion, The Affiliated Hospital of Guizhou Medical University, Guiyang, Guizhou, China.
| | - Tingting Ren
- Guizhou Medical University, Guiyang, Guizhou, China.
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Prasun P. Mitochondrial dysfunction in metabolic syndrome. Biochim Biophys Acta Mol Basis Dis 2020; 1866:165838. [PMID: 32428560 DOI: 10.1016/j.bbadis.2020.165838] [Citation(s) in RCA: 141] [Impact Index Per Article: 35.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2019] [Revised: 04/30/2020] [Accepted: 05/05/2020] [Indexed: 12/29/2022]
Abstract
Metabolic syndrome is co-occurrence of obesity, insulin resistance, atherogenic dyslipidemia (high triglyceride, low high density lipoprotein cholesterol), and hypertension. It is a global health problem. An estimated 20%-30% of adults of the world have metabolic syndrome. Metabolic syndrome is associated with increased risk of type 2 diabetes mellitus, nonalcoholic fatty liver disease, myocardial infarction, and stroke. Thus, it is a major cause of morbidity and mortality worldwide. However, molecular pathogenesis of metabolic syndrome is not well known. Recently, there has been interest in the role of mitochondria in pathogenesis of metabolic problems such as obesity, metabolic syndrome, and type 2 diabetes mellitus. Mitochondrial dysfunction contributes to the oxidative stress and systemic inflammation seen in metabolic syndrome. Role of mitochondria in the pathogenesis of metabolic syndrome is intriguing but far from completely understood. However, a better understanding will be very rewarding as it may lead to novel approaches to control this major public health problem. This brief review explores pathogenesis of metabolic syndrome from a mitochondrial perspective.
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Affiliation(s)
- Pankaj Prasun
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, USA.
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Podgorniak T, Brockmann S, Konstantinidis I, Fernandes JMO. Differences in the fast muscle methylome provide insight into sex-specific epigenetic regulation of growth in Nile tilapia during early stages of domestication. Epigenetics 2019; 14:818-836. [PMID: 31131688 PMCID: PMC6597363 DOI: 10.1080/15592294.2019.1618164] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2018] [Revised: 05/02/2019] [Accepted: 05/04/2019] [Indexed: 01/14/2023] Open
Abstract
Growth is a complex trait whose variability within a population cannot be explained solely by genetic variation. Epigenetic regulation is often suggested as an important factor shaping the phenotype, but its association with growth can be highly context- and species-dependent. Nevertheless, the mechanisms involved in epigenetic regulation of growth in fish are poorly understood. We have used reduced representation bisulphite sequencing to determine the genome-wide CpG methylation patterns in male and female Nile tilapia of different sizes but at the same early stage of domestication. The average CpG methylation level in the reduced genome representation was 63% across groups but many sites displayed group-specific methylation patterns. The number of differentially methylated (DM) CpGs was much higher when the interaction between sex and weight was included rather than when these factors were considered separately. There were 1128 DM CpGs between large and small females and 970 DM CpGs between large and small males. We have found many growth-related genes associated with DM CpGs, namely map3k5 and akt3 in females and gadd45g and ppargc1a in males. Only 5% of CpG locations associated with growth were common to both sexes. In particular, the autophagy-related gene atg14 displayed a high association of methylation with growth exclusively in males. The sexually dimorphic association between atg14 methylation and growth may uncover novel metabolic mechanisms at play during mouth brooding in Nile tilapia females. Taken together, our data suggest that epigenetic regulation of growth in Nile tilapia involves different gene networks in males and females.
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Affiliation(s)
- Tomasz Podgorniak
- Genomics Division, Faculty of Biosciences and Aquaculture, Nord University, Bodø, Norway
| | - Sven Brockmann
- Genomics Division, Faculty of Biosciences and Aquaculture, Nord University, Bodø, Norway
| | - Ioannis Konstantinidis
- Genomics Division, Faculty of Biosciences and Aquaculture, Nord University, Bodø, Norway
| | - Jorge M. O. Fernandes
- Genomics Division, Faculty of Biosciences and Aquaculture, Nord University, Bodø, Norway
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Allan R, Sharples AP, Cocks M, Drust B, Dutton J, Dugdale HF, Mawhinney C, Clucas A, Hawkins W, Morton JP, Gregson W. Low pre-exercise muscle glycogen availability offsets the effect of post-exercise cold water immersion in augmenting PGC-1α gene expression. Physiol Rep 2019; 7:e14082. [PMID: 31161726 PMCID: PMC6546967 DOI: 10.14814/phy2.14082] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2019] [Revised: 04/08/2019] [Accepted: 04/10/2019] [Indexed: 02/07/2023] Open
Abstract
We assessed the effects of post-exercise cold-water immersion (CWI) in modulating PGC-1α mRNA expression in response to exercise commenced with low muscle glycogen availability. In a randomized repeated-measures design, nine recreationally active males completed an acute two-legged high-intensity cycling protocol (8 × 5 min at 82.5% peak power output) followed by 10 min of two-legged post-exercise CWI (8°C) or control conditions (CON). During each trial, one limb commenced exercise with low (LOW: <300 mmol·kg-1 dw) or very low (VLOW: <150 mmol·kg-1 dw) pre-exercise glycogen concentration, achieved via completion of a one-legged glycogen depletion protocol undertaken the evening prior. Exercise increased (P < 0.05) PGC-1α mRNA at 3 h post-exercise. Very low muscle glycogen attenuated the increase in PGC-1α mRNA expression compared with the LOW limbs in both the control (CON VLOW ~3.6-fold vs. CON LOW ~5.6-fold: P = 0.023, ES 1.22 Large) and CWI conditions (CWI VLOW ~2.4-fold vs. CWI LOW ~8.0 fold: P = 0.019, ES 1.43 Large). Furthermore, PGC-1α mRNA expression in the CWI-LOW trial was not significantly different to the CON LOW limb (P = 0.281, ES 0.67 Moderate). Data demonstrate that the previously reported effects of post-exercise CWI on PGC-1α mRNA expression (as regulated systemically via β-adrenergic mediated cell signaling) are offset in those conditions in which local stressors (i.e., high-intensity exercise and low muscle glycogen availability) have already sufficiently activated the AMPK-PGC-1α signaling axis. Additionally, data suggest that commencing exercise with very low muscle glycogen availability attenuates PGC-1α signaling.
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Affiliation(s)
- Robert Allan
- Research Institute for Sport and Exercise SciencesLiverpool John Moores UniversityLiverpoolUK
- Division of Sport, Exercise and Nutritional SciencesUniversity of Central LancashirePrestonUK
| | - Adam P. Sharples
- Research Institute for Sport and Exercise SciencesLiverpool John Moores UniversityLiverpoolUK
- Institute for Science & Technology in MedicineSchool of MedicineKeele UniversityStaffordshireUK
| | - Matthew Cocks
- Research Institute for Sport and Exercise SciencesLiverpool John Moores UniversityLiverpoolUK
| | - Barry Drust
- Research Institute for Sport and Exercise SciencesLiverpool John Moores UniversityLiverpoolUK
| | - John Dutton
- Norwich Medical SchoolUniversity of East AngliaNorwichUK
| | - Hannah F. Dugdale
- Research Institute for Sport and Exercise SciencesLiverpool John Moores UniversityLiverpoolUK
- Medical Research Council Functional Genomics UnitDepartment of Physiology, Anatomy and GeneticsUniversity of OxfordOxfordUK
| | - Chris Mawhinney
- Research Institute for Sport and Exercise SciencesLiverpool John Moores UniversityLiverpoolUK
- College of Sports Science and TechnologyMahidol UniversityNakhon PathomThailand
| | - Angela Clucas
- Research Institute for Sport and Exercise SciencesLiverpool John Moores UniversityLiverpoolUK
| | - Will Hawkins
- Research Institute for Sport and Exercise SciencesLiverpool John Moores UniversityLiverpoolUK
| | - James P. Morton
- Research Institute for Sport and Exercise SciencesLiverpool John Moores UniversityLiverpoolUK
| | - Warren Gregson
- Research Institute for Sport and Exercise SciencesLiverpool John Moores UniversityLiverpoolUK
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Vanlieshout TL, Stouth DW, Tajik T, Ljubicic V. Exercise-induced Protein Arginine Methyltransferase Expression in Skeletal Muscle. Med Sci Sports Exerc 2018; 50:447-457. [PMID: 29112628 DOI: 10.1249/mss.0000000000001476] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
PURPOSE This study aimed to determine protein arginine methyltransferase 1 (PRMT1), -4 (also known as coactivator-associated arginine methyltransferase 1 [CARM1]), and -5 expression and function during acute, exercise-induced skeletal muscle remodeling in vivo. METHODS C57BL/6 mice were assigned to one of three experimental groups: sedentary, acute bout of exercise, or acute exercise followed by 3 h of recovery. Mice in the exercise groups performed a single bout of treadmill running at 15 m·min for 90 min. Hindlimb muscles were collected, and quantitative real-time polymerase chain reaction and Western blotting were used to examine exercise-induced gene expression. RESULTS The PRMT gene expression and global enzyme activity were muscle-specific, generally being higher (P < 0.05) in slow, oxidative muscle, as compared with faster, more glycolytic tissue. Despite the significant activation of canonical exercise-induced signaling involving AMP-activated protein kinase and peroxisome proliferator-activated receptor γ coactivator-1α (PGC-1α), PRMT expression and activity at the whole muscle level were unchanged. However, subcellular analyses revealed a significant exercise-evoked myonuclear translocation of PRMT1 before the nuclear accumulation of PGC-1α. Acute physical activity also augmented (P < 0.05) the targeted methyltransferase activities of the PRMT in the myonuclear compartment, suggesting that PRMT-mediated histone arginine methylation is part of the early signals that drive muscle plasticity. Finally, basal PGC-1α asymmetric dimethylarginine status, as well as constitutive interactions between PGC-1α and PRMT1 or CARM1 may contribute to the exercise-induced muscle remodeling process. CONCLUSIONS The present study provides the first evidence that PRMT activity is selectively augmented during the initial activation of exercise-induced skeletal muscle remodeling in vivo. These data support the emergence of PRMTs as important players in the regulation of skeletal muscle plasticity.
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Bianchi VE. Weight loss is a critical factor to reduce inflammation. Clin Nutr ESPEN 2018; 28:21-35. [DOI: 10.1016/j.clnesp.2018.08.007] [Citation(s) in RCA: 57] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2018] [Accepted: 08/14/2018] [Indexed: 01/14/2023]
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Sun J, Zhang C, Kim M, Su Y, Qin L, Dong J, Zhou Y, Ding S. Early potential effects of resveratrol supplementation on skeletal muscle adaptation involved in exercise-induced weight loss in obese mice. BMB Rep 2018. [PMID: 29519293 PMCID: PMC5933216 DOI: 10.5483/bmbrep.2018.51.4.236] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Exercise and resveratrol supplementation exhibit anti-obesity functions in the long term but have not been fully investigated yet in terms of their early potential effectiveness. Mice fed with high-fat diet were categorized into control (Cont), exercise (Ex), resveratrol supplementation (Res), and exercise combined with resveratrol supplementation (Ex + Res) groups. In the four-week period of weight loss, exercise combined with resveratrol supplementation exerted no additional effects on body weight loss but significantly improved whole-body glucose and lipid homeostasis. The combined treatment significantly decreased intrahepatic lipid content but did not affect intramyocellular lipid content. Moreover, the treatment significantly increased the contents of mtDNA and cytochrome c, the expression levels of peroxisome proliferator-activated receptor gamma coactivator-1 alpha and its downstream transcription factors, and the activities of ATPase and citrate synthase. However, exercise, resveratrol, and their combination did not promote myofiber specification toward slow-twitch type. The effects of exercise combined with resveratrol supplementation on weight loss could be partly due to enhanced mitochondrial biogenesis and not to fiber-type shift in skeletal muscle tissues.
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Affiliation(s)
- Jingyu Sun
- Sports and Health Research Center, Tongji University Department of Physical Education, Shanghai 200092, China
| | - Chen Zhang
- Tongji University School of Medicine, Shanghai 200092, China
| | - MinJeong Kim
- Chung-Ang University College of Medicine, Seoul 06973, Korea
| | - Yajuan Su
- Tongji University School of Life Sciences and Technology, Shanghai 200092, China
| | - Lili Qin
- Sports and Health Research Center, Tongji University Department of Physical Education, Shanghai 200092, China
| | - Jingmei Dong
- Sports and Health Research Center, Tongji University Department of Physical Education, Shanghai 200092, China
| | - Yunhe Zhou
- Sports and Health Research Center, Tongji University Department of Physical Education, Shanghai 200092, China
| | - Shuzhe Ding
- Key Laboratory of Adolescent Health Assessment and Exercise Intervention, East China Normal University, Shanghai 200241, China
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12
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Wang JL, Chen CW, Tsai MR, Liu SF, Hung TJ, Yu-Ju-Hung, Chang WT, Shi MD, Hsieh PF, Yang YL. Antifibrotic role of PGC-1α-siRNA against TGF-β1-induced renal interstitial fibrosis. Exp Cell Res 2018; 370:160-167. [PMID: 29913155 DOI: 10.1016/j.yexcr.2018.06.016] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2017] [Revised: 06/14/2018] [Accepted: 06/15/2018] [Indexed: 12/19/2022]
Abstract
Peroxisome proliferator-activated receptor coactivator-1 alpha (PGC-1α) is a transcriptional coactivator that regulates energy metabolism and mitochondrial biogenesis. Recently, mitochondrial dysfunction has been indicated as an established risk factor for the development of renal fibrosis. However, whether PGC-1α is involved in the pathogenesis of renal fibrosis is unknown. In this study, we treated NRK-49F (normal rat kidney fibroblast) cells with transforming growth factor-beta 1 (TGF-β1) for 24 h to establish an in vitro fibrosis model. TGF-β1 induced the upregulation of type I collagen, fibronectin, TGF-β receptor I (TGFβ-RI), TGFβ-RII, Smad4, and pSmad2/3, as well as PGC-1α. NRK-49F cells transfected with pcDNA-PGC-1α showed significantly increased expression of fibronectin and type I collagen, as revealed by western blot assay. Interestingly, transfection with PGC-1α-siRNA caused a stark reversal of TGF-β1-induced cellular fibrosis, with concomitant suppression of fibronectin and type I collagen, as revealed by western blot and immunofluorescence assays. Moreover, SB431542 (TGFβ-RI), LY294002 (PI3K/Akt), and SB203580 (p38 MAPK), inhibitors of TGF-β-associated pathways, markedly suppressed TGF-β1-induced PGC-1α upregulation. These results implicate a role of PGC-1α in renal interstitial fibrosis mediated via the TGFβ-RI, PI3K/Akt, and p38 MAPK pathways. Our findings that PGC-1α-siRNA downregulates fibronectin and type I collagen suggest that it can be used as a novel molecular treatment for renal fibrosis.
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Affiliation(s)
- Jue-Long Wang
- Department of Physical Medicine and Rehabilitation, Kaohsiung Veterans General Hospital, Tainan, Taiwan, ROC; Department of Nursing, Chung-Hwa University of Medical Technology, Tainan, Taiwan, ROC.
| | - Chin-Wang Chen
- Department of Surgery, Kaohsiung Veterans General Hospital, Tainan, Taiwan, ROC
| | - Mu-Rou Tsai
- Graduate Institute of Biomedical Science, Chung-Hwa University of Medical Technology, Tainan, Taiwan, ROC
| | - Shu-Fen Liu
- Division of Hepato-Biliary-Pancreatic Medicine, Kaoshiung Medical University Chung-Ho Memorial Hospital, Kaohsiung, Taiwan, ROC
| | - Tsung-Jeu Hung
- Department of Early Childhood Caring and Education, Chung Hwa University of Medical Technology, Tainan, Taiwan, ROC
| | - Yu-Ju-Hung
- Graduate Institute of Biomedical Science, Chung-Hwa University of Medical Technology, Tainan, Taiwan, ROC; Department of Public Health, National Taiwan University, Taipei, Taiwan, ROC
| | - Wen-Teng Chang
- Graduate Institute of Biomedical Science, Chung-Hwa University of Medical Technology, Tainan, Taiwan, ROC
| | - Ming-Der Shi
- Department of Medical Laboratory Science and Biotechnology, Chung-Hwa University of Medical Technology, Tainan, Taiwan, ROC; Department of Medical Technology, Kaohsiung Veterans General Hospital Tainan Branch, Tainan, Taiwan, ROC
| | - Pei-Fang Hsieh
- Department of Medical Laboratory Science and Biotechnology, Chung-Hwa University of Medical Technology, Tainan, Taiwan, ROC; Graduate Institute of Biomedical Science, National Sun Yat-sen University, Kaohsiung, Taiwan, ROC
| | - Yu-Lin Yang
- Graduate Institute of Biomedical Science, Chung-Hwa University of Medical Technology, Tainan, Taiwan, ROC; Department of Medical Laboratory Science and Biotechnology, Chung-Hwa University of Medical Technology, Tainan, Taiwan, ROC.
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13
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Andersson EA, Frank P, Pontén M, Ekblom B, Ekblom M, Moberg M, Sahlin K. Improving Strength, Power, Muscle Aerobic Capacity, and Glucose Tolerance through Short-term Progressive Strength Training Among Elderly People. J Vis Exp 2017. [PMID: 28715403 DOI: 10.3791/55518] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
This protocol describes the simultaneous use of a broad span of methods to examine muscle aerobic capacity, glucose tolerance, strength, and power in elderly people performing short-term resistance training (RET). Supervised progressive resistance training for 1 h three times a week over 8 weeks was performed by RET participants (71±1 years, range 65-80). Compared to a control group without training, the RET showed improvements on the measures used to indicate strength, power, glucose tolerance, and several parameters of muscle aerobic capacity. Strength training was performed in a gym with only robust fitness equipment. An isokinetic dynamometer for knee extensor strength permitted the measurement of concentric, eccentric, and static strength, which increased for the RET group (8-12% post- versus pre-test). The power (rate of force development, RFD) at the initial 0-30 ms also showed an increase for the RET group (52%). A glucose tolerance test with frequent blood glucose measurements showed improvements only for the RET group in terms of blood glucose values after 2 h (14%) and the area under the curve (21%). The blood lipid profile also improved (8%). From muscle biopsy samples prepared using histochemistry, the amount of fiber type IIa increased, and a trend towards a decrease in IIx in the RET group reflected a change to a more oxidative profile in terms of fiber composition. Western blot (to determine the protein content related to the signaling for muscle protein synthesis) showed a rise of 69% in both Akt and mTOR in the RET group; this also showed an increase in mitochondrial proteins for OXPHOS complex II and citrate synthase (both ~30%) and for complex IV (90%), in only the RET group. We demonstrate that this type of progressive resistance training offers various improvements (e.g., strength, power, aerobic capacity, glucose tolerance, and plasma lipid profile).
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Affiliation(s)
- Eva A Andersson
- Åstrand Laboratory of Work Physiology, The Swedish School of Sport and Health Sciences, GIH; Department of Neuroscience, Karolinska Institutet;
| | - Per Frank
- Åstrand Laboratory of Work Physiology, The Swedish School of Sport and Health Sciences, GIH; Department of Physiology and Pharmacology, Karolinska Institutet
| | - Marjan Pontén
- Åstrand Laboratory of Work Physiology, The Swedish School of Sport and Health Sciences, GIH
| | - Björn Ekblom
- Åstrand Laboratory of Work Physiology, The Swedish School of Sport and Health Sciences, GIH
| | - Maria Ekblom
- Åstrand Laboratory of Work Physiology, The Swedish School of Sport and Health Sciences, GIH; Department of Neuroscience, Karolinska Institutet
| | - Marcus Moberg
- Åstrand Laboratory of Work Physiology, The Swedish School of Sport and Health Sciences, GIH
| | - Kent Sahlin
- Åstrand Laboratory of Work Physiology, The Swedish School of Sport and Health Sciences, GIH
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14
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Scribbans TD, Edgett BA, Bonafiglia JT, Baechler BL, Quadrilatero J, Gurd BJ. A systematic upregulation of nuclear and mitochondrial genes is not present in the initial postexercise recovery period in human skeletal muscle. Appl Physiol Nutr Metab 2017; 42:571-578. [DOI: 10.1139/apnm-2016-0455] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The purpose of the current investigation was to determine if an exercise-mediated upregulation of nuclear and mitochondrial-encoded genes targeted by the transcriptional co-activator peroxisome-proliferator-activated receptor gamma co-activator-1 alpha (PGC-1α) occurs in a systematic manner following different exercise intensities in humans. Ten recreationally active males (age: 23 ± 3 years; peak oxygen uptake: 41.8 ± 6.6 mL·kg−1·min−1) completed 2 acute bouts of work-matched interval exercise at ∼73% (low; LO) and ∼100% (high; HI) of work rate at peak oxygen uptake in a randomized crossover design. Muscle biopsies were taken before, immediately after, and 3 h into recovery following each exercise bout. A main effect of time (p < 0.05) was observed for glycogen depletion. PGC-1α messenger RNA (mRNA) increased following both conditions and was significantly (p < 0.05) higher following HI compared with LO (PGC-1α, LO: +442% vs. HI: +845%). PDK4 mRNA increased following LO whereas PPARα, NRF1, and CS increased following HI. However, a systematic upregulation of nuclear and mitochondrial-encoded genes was not present as TFAM, COXIV, COXI, COXII, ND1, and ND4 mRNA were unchanged. However, changes in COXI, COXII, ND1 and ND4 mRNA were positively correlated following LO and COXI, ND1, and ND4 were positively correlated following HI, which suggests mitochondrial-encoded gene expression was coordinated. PGC-1α and ND4 mRNA, as well as PGC-1α mRNA and the change in muscle glycogen, were positively correlated in response to LO. The lack of observed systematic upregulation of nuclear- and mitochondrial-encoded genes suggests that exercise-induced upregulation of PGC-1α targets are differentially regulated during the initial hours following acute exercise in humans.
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Affiliation(s)
- Trisha D. Scribbans
- School of Kinesiology and Health Studies, Queen’s University, Kingston, ON K7L 3N6, Canada
| | - Brittany A. Edgett
- School of Kinesiology and Health Studies, Queen’s University, Kingston, ON K7L 3N6, Canada
| | - Jacob T. Bonafiglia
- School of Kinesiology and Health Studies, Queen’s University, Kingston, ON K7L 3N6, Canada
| | | | - Joe Quadrilatero
- Department of Kinesiology, University of Waterloo, Waterloo, ON N2L 3G1, Canada
| | - Brendon J. Gurd
- School of Kinesiology and Health Studies, Queen’s University, Kingston, ON K7L 3N6, Canada
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15
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Saner NJ, Bishop DJ, Bartlett JD. Is exercise a viable therapeutic intervention to mitigate mitochondrial dysfunction and insulin resistance induced by sleep loss? Sleep Med Rev 2017; 37:60-68. [PMID: 29056415 DOI: 10.1016/j.smrv.2017.01.001] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2016] [Revised: 12/16/2016] [Accepted: 01/10/2017] [Indexed: 12/18/2022]
Abstract
Sleep loss has emerged as a risk factor comparable to that of physical inactivity for the development of insulin resistance, impaired glucose tolerance and type 2 diabetes mellitus. This is a concern as it was estimated in 2012 that approximately 70 million adults in the United States are sleeping less than 6 h each night, and the average nightly sleep duration of a representative sample of the U.S. adult population is reported to be significantly less than in previous decades. The underlying mechanisms responsible for chronic sleep loss induced insulin resistance include modifications in the regulation of hormone secretion, peripheral clock gene regulation, and the cellular signaling processes associated with regulating mitochondrial respiratory function. Emerging evidence shows these mechanisms share similar biochemical signaling pathways to those underpinning exercise-induced adaptations, which together suggest exercise might be a viable, suitable, and potent treatment alternative to alleviate sleep loss induced insulin resistance and glucose intolerance. In this theoretical review, we provide a summary of the impact of reduced sleep duration and quality on mitochondrial function and insulin resistance, before detailing the possible underlying mechanisms. Finally, we propose how and why regular exercise may be a therapeutic intervention to mitigate sleep loss induced mitochondrial dysfunction and insulin resistance.
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Affiliation(s)
- Nicholas J Saner
- Institute of Sport, Exercise and Active Living (ISEAL), College of Sport and Exercise Science, Victoria University, Melbourne, Australia
| | - David J Bishop
- Institute of Sport, Exercise and Active Living (ISEAL), College of Sport and Exercise Science, Victoria University, Melbourne, Australia; School of Medicine and Health Sciences, Edith Cowan University, 270 Joondalup Drive, Joondalup, 6027, Australia
| | - Jonathan D Bartlett
- Institute of Sport, Exercise and Active Living (ISEAL), College of Sport and Exercise Science, Victoria University, Melbourne, Australia.
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16
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Tischner C, Wenz T. Keep the fire burning: Current avenues in the quest of treating mitochondrial disorders. Mitochondrion 2015; 24:32-49. [DOI: 10.1016/j.mito.2015.06.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2015] [Revised: 06/18/2015] [Accepted: 06/24/2015] [Indexed: 12/18/2022]
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17
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Frank P, Andersson E, Pontén M, Ekblom B, Ekblom M, Sahlin K. Strength training improves muscle aerobic capacity and glucose tolerance in elderly. Scand J Med Sci Sports 2015; 26:764-73. [PMID: 26271931 DOI: 10.1111/sms.12537] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/16/2015] [Indexed: 12/11/2022]
Abstract
The primary aim of this study was to investigate the effect of short-term resistance training (RET) on mitochondrial protein content and glucose tolerance in elderly. Elderly women and men (age 71 ± 1, mean ± SEM) were assigned to a group performing 8 weeks of resistance training (RET, n = 12) or no training (CON, n = 9). The RET group increased in (i) knee extensor strength (concentric +11 ± 3%, eccentric +8 ± 3% and static +12 ± 3%), (ii) initial (0-30 ms) rate of force development (+52 ± 26%) and (iii) contents of proteins related to signaling of muscle protein synthesis (Akt +69 ± 20 and mammalian target of rapamycin +69 ± 32%). Muscle fiber type composition changed to a more oxidative profile in RET with increased amount of type IIa fibers (+26.9 ± 6.8%) and a trend for decreased amount of type IIx fibers (-16.4 ± 18.2%, P = 0.068). Mitochondrial proteins (OXPHOS complex II, IV, and citrate synthase) increased in RET by +30 ± 11%, +99 ± 31% and +29 ± 8%, respectively. RET resulted in improved oral glucose tolerance measured as reduced area under curve for glucose (-21 ± 26%) and reduced plasma glucose 2 h post-glucose intake (-14 ± 5%). In CON parameters were unchanged or impaired. In conclusion, short-term resistance training in elderly not only improves muscular strength, but results in robust increases in several parameters related to muscle aerobic capacity.
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Affiliation(s)
- P Frank
- Åstrand Laboratory of Work Physiology, The Swedish School of Sport and Health Sciences, GIH, Stockholm, Sweden.,Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - E Andersson
- Åstrand Laboratory of Work Physiology, The Swedish School of Sport and Health Sciences, GIH, Stockholm, Sweden.,Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - M Pontén
- Åstrand Laboratory of Work Physiology, The Swedish School of Sport and Health Sciences, GIH, Stockholm, Sweden
| | - B Ekblom
- Åstrand Laboratory of Work Physiology, The Swedish School of Sport and Health Sciences, GIH, Stockholm, Sweden
| | - M Ekblom
- Åstrand Laboratory of Work Physiology, The Swedish School of Sport and Health Sciences, GIH, Stockholm, Sweden
| | - K Sahlin
- Åstrand Laboratory of Work Physiology, The Swedish School of Sport and Health Sciences, GIH, Stockholm, Sweden
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18
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Peralta S, Torraco A, Iommarini L, Diaz F. Mitochondrial Diseases Part III: Therapeutic interventions in mouse models of OXPHOS deficiencies. Mitochondrion 2015; 23:71-80. [PMID: 25638392 DOI: 10.1016/j.mito.2015.01.007] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2015] [Accepted: 01/22/2015] [Indexed: 12/19/2022]
Abstract
Mitochondrial defects are the cause of numerous disorders affecting the oxidative phosphorylation system (OXPHOS) in humans leading predominantly to neurological and muscular degeneration. The molecular origin, manifestations, and progression of mitochondrial diseases have a broad spectrum, which makes very challenging to find a globally effective therapy. The study of the molecular mechanisms underlying the mitochondrial dysfunction indicates that there is a wide range of pathways, enzymes and molecules that can be potentially targeted for therapeutic purposes. Therefore, focusing on the pathology of the disease is essential to design new treatments. In this review, we will summarize and discuss the different therapeutic interventions tested in some mouse models of mitochondrial diseases emphasizing the molecular mechanisms of action and their potential applications.
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Affiliation(s)
- Susana Peralta
- Department of Neurology, University of Miami, Miller School of Medicine, Miami, FL 33136, USA.
| | - Alessandra Torraco
- Neuromuscular and Neurodegenerative Disorders, Laboratory of Molecular Medicine, Bambino Gesù Children's Hospital, IRCCS, Viale di San Paolo, 15 - 00146, Rome, Italy.
| | - Luisa Iommarini
- Department of Pharmacy and Biotechnology (FABIT), University of Bologna, Via Irnerio 42, 40126, Bologna, Italy.
| | - Francisca Diaz
- Department of Neurology, University of Miami, Miller School of Medicine, Miami, FL 33136, USA.
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19
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Jeong TS, Bartlett JD, Joo CH, Louhelainen J, Close GL, Morton JP, Drust B. Acute simulated soccer-specific training increases PGC-1α mRNA expression in human skeletal muscle. J Sports Sci 2014; 33:1493-503. [DOI: 10.1080/02640414.2014.992937] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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20
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SIRT3 protects cells from hypoxia via PGC-1α- and MnSOD-dependent pathways. Neuroscience 2014; 286:109-21. [PMID: 25433241 DOI: 10.1016/j.neuroscience.2014.11.045] [Citation(s) in RCA: 63] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2014] [Revised: 11/13/2014] [Accepted: 11/15/2014] [Indexed: 02/08/2023]
Abstract
Reports suggest that silent information regulation 2 homolog 3 (SIRT3) protects cardiomyocytes from oxidative stress-mediated death. SIRT3, a mitochondrial protein, is an essential regulator of mitochondrial function, and this regulation is important in many cerebrovascular diseases, especially stroke. Here, we investigated the role of SIRT3 in ischemia-induced neuronal death due to oxygen-glucose deprivation (OGD) using an in vitro model of cerebral ischemia. We found that exposure of differentiated PC12 cells to OGD for 6h caused a marked decrease in cell viability and up regulated SIRT3. SIRT3 knockdown using short interfering RNA (siRNA) exacerbated OGD-induced injury whereas application of recombinant SIRT3 protected against OGD-induced cell death. Pre-treatment of the cells in which the SIRT3 gene was knocked down with recombinant SIRT3 before OGD partially restored cell viability and concomitantly reduced lactate dehydrogenase (LDH) release and increased ATP generation in mitochondria. Recombinant SIRT3 treatment resulted in increased expression of peroxisome proliferator activated receptor (PPAR)-γ co-activator 1-α (PGC-1α) and manganese superoxide dismutase (MnSOD). After knockdown of PGC-1α or MnSOD, recombinant SIRT3 failed to protect against OGD-induced injury. We also found that the protein and mRNA expression of PGC-1α was down regulated following SIRT3 knockdown. The expression level of SIRT3 was reduced when the PGC-1α gene was knocked down. Both SIRT3 and PGC-1α knockdown led to reduced mitochondrial membrane potential (Δψ) and Ca(2+) transients, especially under OGD conditions. Thus, our data suggest that SIRT3 protects PC12 cells from hypoxic injury via a mechanism that may involve PGC-1α and MnSOD. SIRT3 and PGC-1α regulate each other under physiologic and OGD conditions, thereby partially protecting against hypoxia or ischemia.
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21
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Maher AC, McFarlan J, Lally J, Snook LA, Bonen A. TBC1D1 reduces palmitate oxidation by inhibiting β-HAD activity in skeletal muscle. Am J Physiol Regul Integr Comp Physiol 2014; 307:R1115-23. [PMID: 25163918 DOI: 10.1152/ajpregu.00014.2014] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
In skeletal muscle the Rab-GTPase-activating protein TBC1D1 has been implicated in the regulation of fatty acid oxidation by an unknown mechanism. We determined whether TBC1D1 altered fatty acid utilization via changes in protein-mediated fatty acid transport and/or selected enzymes regulating mitochondrial fatty acid oxidation. We also determined the effects of TBC1D1 on glucose transport and oxidation. Electrotransfection of mouse soleus muscles with TBC1D1 cDNA increased TBC1D1 protein after 2 wk (P<0.05), without altering its paralog AS160. TBC1D1 overexpression decreased basal palmitate oxidation (-22%) while blunting 5-aminoimidazole-4-carboxamide ribonucleotide (AICAR)-stimulated palmitate oxidation (-18%). There was a tendency to increase fatty acid esterification (+10 nmol·g(-1)·60 min(-1), P=0.07), which reflected the reduction in fatty acid oxidation (-12 nmol·g(-1)·60 min(-1)). Concomitantly, basal (+21%) and AICAR-stimulated glucose oxidation (+8%) were increased in TBC1D1-transfected muscles relative to their respective controls (P<0.05), independent of changes in GLUT4 and glucose transport. The reductions in TBC1D1-mediated fatty acid oxidation could not be attributed to changes in the transporter FAT/CD36, muscle mitochondrial content, CPT1 expression or the expression and phosphorylation of AS160, acetyl-CoA carboxylase, or AMPK. However, TBC1D1 overexpression reduced β-HAD enzyme activity (-18%, P<0.05). In conclusion, TBC1D1-mediated reduction of muscle fatty acid oxidation appears to occur via inhibition of β-HAD activity.
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Affiliation(s)
- A C Maher
- Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario, Canada
| | - J McFarlan
- Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario, Canada
| | - J Lally
- Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario, Canada
| | - L A Snook
- Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario, Canada
| | - A Bonen
- Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario, Canada
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22
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Conner JD, Wolden-Hanson T, Quinn LS. Assessment of murine exercise endurance without the use of a shock grid: an alternative to forced exercise. J Vis Exp 2014:e51846. [PMID: 25145813 DOI: 10.3791/51846] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
Using laboratory mouse models, the molecular pathways responsible for the metabolic benefits of endurance exercise are beginning to be defined. The most common method for assessing exercise endurance in mice utilizes forced running on a motorized treadmill equipped with a shock grid. Animals who quit running are pushed by the moving treadmill belt onto a grid that delivers an electric foot shock; to escape the negative stimulus, the mice return to running on the belt. However, avoidance behavior and psychological stress due to use of a shock apparatus can interfere with quantitation of running endurance, as well as confound measurements of postexercise serum hormone and cytokine levels. Here, we demonstrate and validate a refined method to measure running endurance in naïve C57BL/6 laboratory mice on a motorized treadmill without utilizing a shock grid. When mice are preacclimated to the treadmill, they run voluntarily with gait speeds specific to each mouse. Use of the shock grid is replaced by gentle encouragement by a human operator using a tongue depressor, coupled with sensitivity to the voluntary willingness to run on the part of the mouse. Clear endpoints for quantifying running time-to-exhaustion for each mouse are defined and reflected in behavioral signs of exhaustion such as splayed posture and labored breathing. This method is a humane refinement which also decreases the confounding effects of stress on experimental parameters.
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Affiliation(s)
- Jennifer D Conner
- Research Service, VA Puget Sound Health Care System; Seattle Institute for Biomedical and Clinical Research
| | | | - LeBris S Quinn
- Research Service, VA Puget Sound Health Care System; Division of Gerontology and Geriatric Medicine, Department of Medicine, University of Washington; Geriatric Research, Education, and Clinical Center, VA Puget Sound Health Care System;
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23
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Paoli A, Bianco A, Damiani E, Bosco G. Ketogenic diet in neuromuscular and neurodegenerative diseases. BIOMED RESEARCH INTERNATIONAL 2014; 2014:474296. [PMID: 25101284 PMCID: PMC4101992 DOI: 10.1155/2014/474296] [Citation(s) in RCA: 130] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/24/2014] [Accepted: 05/30/2014] [Indexed: 12/14/2022]
Abstract
An increasing number of data demonstrate the utility of ketogenic diets in a variety of metabolic diseases as obesity, metabolic syndrome, and diabetes. In regard to neurological disorders, ketogenic diet is recognized as an effective treatment for pharmacoresistant epilepsy but emerging data suggests that ketogenic diet could be also useful in amyotrophic lateral sclerosis, Alzheimer, Parkinson's disease, and some mitochondriopathies. Although these diseases have different pathogenesis and features, there are some common mechanisms that could explain the effects of ketogenic diets. These mechanisms are to provide an efficient source of energy for the treatment of certain types of neurodegenerative diseases characterized by focal brain hypometabolism; to decrease the oxidative damage associated with various kinds of metabolic stress; to increase the mitochondrial biogenesis pathways; and to take advantage of the capacity of ketones to bypass the defect in complex I activity implicated in some neurological diseases. These mechanisms will be discussed in this review.
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Affiliation(s)
- Antonio Paoli
- Department of Biomedical Sciences, University of Padova, Via Marzolo 3, 35031 Padova, Italy
| | - Antonino Bianco
- Sport and Exercise Sciences Research Unit, University of Palermo, Via Eleonora Duse 2, 90146 Palermo, Italy
| | - Ernesto Damiani
- Department of Biomedical Sciences, University of Padova, Via Marzolo 3, 35031 Padova, Italy
| | - Gerardo Bosco
- Department of Biomedical Sciences, University of Padova, Via Marzolo 3, 35031 Padova, Italy
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24
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Buler M, Aatsinki SM, Izzi V, Uusimaa J, Hakkola J. SIRT5 is under the control of PGC-1α and AMPK and is involved in regulation of mitochondrial energy metabolism. FASEB J 2014; 28:3225-37. [PMID: 24687991 DOI: 10.1096/fj.13-245241] [Citation(s) in RCA: 95] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2023]
Abstract
The sirtuins (SIRTs; SIRT1-7) are a family of NAD(+)-dependent enzymes that dynamically regulate cellular physiology. Apart from SIRT1, the functions and regulatory mechanisms of the SIRTs are poorly defined. We explored regulation of the SIRT family by 2 energy metabolism-controlling factors: peroxisome proliferator-activated receptor γ coactivator 1-α (PGC-1α) and AMP-activated protein kinase (AMPK). Overexpression of PGC-1α in mouse primary hepatocytes increased SIRT5 mRNA expression 4-fold and also the protein in a peroxisome proliferator-activated receptor α (PPARα)- and estrogen-related receptor α (ERRα)-dependent manner. Furthermore, food withdrawal increased SIRT5 mRNA 1.3-fold in rat liver. Overexpression of AMPK in mouse hepatocytes increased expression of SIRT1, SIRT2, SIRT3, and SIRT6 <2-fold. In contrast, SIRT5 mRNA was down-regulated by 58%. The antidiabetes drug metformin (1 mM), an established AMPK activator, reduced the mouse SIRT5 protein level by 44% in cultured hepatocytes and by 31% in liver in vivo (300 mg/kg, 7 d). Metformin also induced hypersuccinylation of mitochondrial proteins. Moreover, SIRT5 overexpression increased ATP synthesis and oxygen consumption in HepG2 cells, but did not affect mitochondrial biogenesis. In summary, our results identified SIRT5 as a novel factor that controls mitochondrial function. Moreover, SIRT5 levels are regulated by PGC-1α and AMPK, which have opposite effects on its expression.-Buler, M., Aatsinki, S.-M., Izzi, V., Uusimaa, J., Hakkola, J. SIRT5 is under the control of PGC-1α and AMPK and is involved in regulation of mitochondrial energy metabolism.
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Affiliation(s)
- Marcin Buler
- Department of Pharmacology and Toxicology, Institute of Biomedicine, Medical Research Center Oulu and
| | - Sanna-Mari Aatsinki
- Department of Pharmacology and Toxicology, Institute of Biomedicine, Medical Research Center Oulu and
| | - Valerio Izzi
- Center for Cell-Matrix Research and Biocenter Oulu, Department of Medical Biochemistry and Molecular Biology, and
| | - Johanna Uusimaa
- Medical Research Center Oulu and Institute of Clinical Medicine and Pediatrics, Clinical Research Center, Oulu University Hospital, University of Oulu, Oulu, Finland
| | - Jukka Hakkola
- Department of Pharmacology and Toxicology, Institute of Biomedicine, Medical Research Center Oulu and
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Quinn LS, Anderson BG, Conner JD, Wolden-Hanson T, Marcell TJ. IL-15 is required for postexercise induction of the pro-oxidative mediators PPARδ and SIRT1 in male mice. Endocrinology 2014; 155:143-55. [PMID: 24169546 PMCID: PMC5378429 DOI: 10.1210/en.2013-1645] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Physical exercise induces transient upregulation of the pro-oxidative mediators peroxisome proliferator-activated receptor-δ (PPARδ), silent information regulator of transcription (sirtuin)-1 (SIRT1), PPARγ coactivator 1α (PGC-1α), and PGC-1β in skeletal muscle. To determine the role of the cytokine IL-15 in acute postexercise induction of these molecules, expression of these factors after a bout of exhaustive treadmill running was examined in the gastrocnemius muscle of untrained control and IL-15-knockout (KO) mice. Circulating IL-15 levels increased transiently in control mice after exercise. Control mice, but not IL-15-KO mice, upregulated muscle PPARδ and SIRT1 protein after exercise, accompanied by a complex pattern of mRNA expression for these factors. However, in exhaustive exercise, control mice ran significantly longer than IL-15-KO mice. Therefore, in a second experiment, mice were limited to a 20-minute run, after which a similar pattern of induction of muscle PPARδ and SIRT1 protein by control mice only was observed. In a separate experiment, IL-15-KO mice injected systemically with recombinant IL-15 upregulated muscle PPARδ and SIRT1 mRNA within 30 minutes and also exhibited increased muscle PPARδ protein levels by 3 hours. After exercise, both control and IL-15-KO mice downregulated IL-15 receptor-α (IL-15Rα) mRNA, whereas IL-15Rα-deficient mice exhibited constitutively elevated circulating IL-15 levels. These observations indicate IL-15 release after exercise is necessary for induction of PPARδ and SIRT1 at the protein level in muscle tissue and suggest that exercise releases IL-15 normally sequestered by the IL-15Rα in the resting state. These findings could be used to develop an IL-15-based strategy to induce many of the metabolic benefits of physical exercise.
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Affiliation(s)
- Lebris S Quinn
- Geriatric Research, Education, and Clinical Center (L.S.Q., B.G.A.) and Research Service (L.S.Q., J.D.C., T.W.-H.), VA Puget Sound Health Care System, and Seattle Institute for Biomedical and Clinical Research (L.S.Q., J.D.C.), Seattle, Washington 98108; Division of Gerontology and Geriatric Medicine (L.S.Q., B.G.A.), Department of Medicine, University of Washington, Seattle, Washington 98195; and Department of Kinesiology (T.J.M.), California State University Stanislaus, Turlock, California 95382
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Cortez M, Singleton JR, Smith AG. Glucose intolerance, metabolic syndrome, and neuropathy. ACTA ACUST UNITED AC 2014; 126:109-22. [DOI: 10.1016/b978-0-444-53480-4.00009-6] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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Romo-Vaquero M, Larrosa M, Yáñez-Gascón MJ, Issaly N, Flanagan J, Roller M, Tomás-Barberán FA, Espín JC, García-Conesa MT. A rosemary extract enriched in carnosic acid improves circulating adipocytokines and modulates key metabolic sensors in lean Zucker rats: Critical and contrasting differences in the obese genotype. Mol Nutr Food Res 2013; 58:942-53. [DOI: 10.1002/mnfr.201300524] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2013] [Revised: 10/02/2013] [Accepted: 10/03/2013] [Indexed: 12/12/2022]
Affiliation(s)
- María Romo-Vaquero
- Research Group on Quality; Safety, and Bioactivity of Plant Foods; Department of Food Science and Technology; CEBAS-CSIC; Murcia Spain
| | - Mar Larrosa
- Research Group on Quality; Safety, and Bioactivity of Plant Foods; Department of Food Science and Technology; CEBAS-CSIC; Murcia Spain
| | - María J. Yáñez-Gascón
- Research Group on Quality; Safety, and Bioactivity of Plant Foods; Department of Food Science and Technology; CEBAS-CSIC; Murcia Spain
| | | | | | | | - Francisco A. Tomás-Barberán
- Research Group on Quality; Safety, and Bioactivity of Plant Foods; Department of Food Science and Technology; CEBAS-CSIC; Murcia Spain
| | - Juan C. Espín
- Research Group on Quality; Safety, and Bioactivity of Plant Foods; Department of Food Science and Technology; CEBAS-CSIC; Murcia Spain
| | - María-Teresa García-Conesa
- Research Group on Quality; Safety, and Bioactivity of Plant Foods; Department of Food Science and Technology; CEBAS-CSIC; Murcia Spain
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Bartlett JD, Close GL, Drust B, Morton JP. The Emerging Role of p53 in Exercise Metabolism. Sports Med 2013; 44:303-9. [DOI: 10.1007/s40279-013-0127-9] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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Fongy A, Romestaing C, Blanc C, Lacoste-Garanger N, Rouanet JL, Raccurt M, Duchamp C. Ontogeny of muscle bioenergetics in Adélie penguin chicks (Pygoscelis adeliae). Am J Physiol Regul Integr Comp Physiol 2013; 305:R1065-75. [DOI: 10.1152/ajpregu.00137.2013] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The ontogeny of pectoralis muscle bioenergetics was studied in growing Adélie penguin chicks during the first month after hatching and compared with adults using permeabilized fibers and isolated mitochondria. With pyruvate-malate-succinate or palmitoyl-carnitine as substrates, permeabilized fiber respiration markedly increased during chick growth (3-fold) and further rose in adults (1.4-fold). Several markers of muscle fiber oxidative activity (cytochrome oxidase, citrate synthase, hydroxyl-acyl-CoA dehydrogenase) increased 6- to 19-fold with age together with large rises in intermyofibrillar (IMF) and subsarcolemmal (SS) mitochondrial content (3- to 5-fold) and oxidative activities (1.5- to 2.4-fold). The proportion of IMF relative to SS mitochondria increased with chick age but markedly dropped in adults. Differences in oxidative activity between mitochondrial fractions were reduced in adults compared with hatched chicks. Extrapolation of mitochondrial to muscle respirations revealed similar figures with isolated mitochondria and permeabilized fibers with carbohydrate-derived but not with lipid-derived substrates, suggesting diffusion limitations of lipid substrates with permeabilized fibers. Two immunoreactive fusion proteins, mitofusin 2 (Mfn2) and optic atrophy 1 (OPA1), were detected by Western blots on mitochondrial extracts and their relative abundance increased with age. Muscle fiber respiration was positively related with Mfn2 and OPA1 relative abundance. Present data showed by two complementary techniques large ontogenic increases in muscle oxidative activity that may enable birds to face thermal emancipation and growth in childhood and marine life in adulthood. The concomitant rise in mitochondrial fusion protein abundance suggests a role of mitochondrial networks in the skeletal muscle processes of bioenergetics that enable penguins to overcome harsh environmental constraints.
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Affiliation(s)
- Anaïs Fongy
- Université de Lyon, Ecologie des Hydrosystèmes Naturels et Anthropisés, Université Lyon 1; Ecole Nationale des Travaux Publics de l'Etat; Centre National de la Recherche Scientifique, Villeurbanne, France
| | - Caroline Romestaing
- Université de Lyon, Ecologie des Hydrosystèmes Naturels et Anthropisés, Université Lyon 1; Ecole Nationale des Travaux Publics de l'Etat; Centre National de la Recherche Scientifique, Villeurbanne, France
| | - Coralie Blanc
- Université de Lyon, Ecologie des Hydrosystèmes Naturels et Anthropisés, Université Lyon 1; Ecole Nationale des Travaux Publics de l'Etat; Centre National de la Recherche Scientifique, Villeurbanne, France
| | - Nicolas Lacoste-Garanger
- Université de Lyon, Ecologie des Hydrosystèmes Naturels et Anthropisés, Université Lyon 1; Ecole Nationale des Travaux Publics de l'Etat; Centre National de la Recherche Scientifique, Villeurbanne, France
| | - Jean-Louis Rouanet
- Université de Lyon, Ecologie des Hydrosystèmes Naturels et Anthropisés, Université Lyon 1; Ecole Nationale des Travaux Publics de l'Etat; Centre National de la Recherche Scientifique, Villeurbanne, France
| | - Mireille Raccurt
- Université de Lyon, Ecologie des Hydrosystèmes Naturels et Anthropisés, Université Lyon 1; Ecole Nationale des Travaux Publics de l'Etat; Centre National de la Recherche Scientifique, Villeurbanne, France
| | - Claude Duchamp
- Université de Lyon, Ecologie des Hydrosystèmes Naturels et Anthropisés, Université Lyon 1; Ecole Nationale des Travaux Publics de l'Etat; Centre National de la Recherche Scientifique, Villeurbanne, France
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Donges CE, Duffield R, Guelfi KJ, Smith GC, Adams DR, Edge JA. Comparative effects of single-mode vs. duration-matched concurrent exercise training on body composition, low-grade inflammation, and glucose regulation in sedentary, overweight, middle-aged men. Appl Physiol Nutr Metab 2013; 38:779-88. [DOI: 10.1139/apnm-2012-0443] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Affiliation(s)
- Cheyne E. Donges
- School of Human Movement Studies, Charles Sturt University, Panorama Avenue, Bathurst, Australia, 2795
| | - Rob Duffield
- School of Human Movement Studies, Charles Sturt University, Panorama Avenue, Bathurst, Australia, 2795
| | - Kym J. Guelfi
- School of Sport Science, Exercise and Health, The University of Western Australia, Perth, Australia
| | - Greg C. Smith
- Department of Molecular Medicine and Pathology, The University of Auckland, New Zealand
| | - David R. Adams
- School of Human Movement Studies, Charles Sturt University, Panorama Avenue, Bathurst, Australia, 2795
| | - Johann A. Edge
- Department of Exercise and Sports Science, The University of Auckland, New Zealand
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Johannsen NM, Sparks LM, Zhang Z, Earnest CP, Smith SR, Church TS, Ravussin E. Determinants of the Changes in Glycemic Control with Exercise Training in Type 2 Diabetes: A Randomized Trial. PLoS One 2013; 8:e62973. [PMID: 23805175 PMCID: PMC3689775 DOI: 10.1371/journal.pone.0062973] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2012] [Accepted: 03/24/2013] [Indexed: 12/26/2022] Open
Abstract
Aims To assess the determinants of exercise training-induced improvements in glucose control (HbA1C) including changes in serum total adiponectin and FFA concentrations, and skeletal muscle peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α) protein content. Methods A sub-cohort (n = 35; 48% men; 74% Caucasian) from the HART-D study undertaking muscle biopsies before and after 9 months of aerobic (AT), resistance (RT), or combination training (ATRT). Results Changes in HbA1C were associated with changes in adiponectin (r = −0.45, P = 0.007). Participants diagnosed with type 2 diabetes for a longer duration had the largest increase in PGC-1α (r = 0.44, P = 0.008). Statistical modeling examining changes in HbA1C suggested that male sex (P = 0.05), non-Caucasian ethnicity (P = 0.02), duration of type 2 diabetes (r = 0.40; P<0.002) and changes in FFA (r = 0.36; P<0.004), adiponectin (r = −0.26; P<0.03), and PGC-1α (r = −0.28; P = 0.02) explain ∼65% of the variability in the changes in HbA1C. Conclusions Decreases in HbA1C after 9 months of exercise were associated with shorter duration of diabetes, lowering of serum FFA concentrations, increasing serum adiponectin concentrations and increasing skeletal muscle PGC-1α protein expression. Trial Registration ClinicalTrials.gov NCT00458133
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Affiliation(s)
- Neil M. Johannsen
- Pennington Biomedical Research Center, Baton Rouge, Louisiana, United States of America
- Louisiana State University, Baton Rouge, Louisiana, United States of America
| | - Lauren M. Sparks
- Translational Research Institute for Metabolism and Diabetes, Orlando, Florida, United States of America
| | - Zhengyu Zhang
- Pennington Biomedical Research Center, Baton Rouge, Louisiana, United States of America
| | | | - Steven R. Smith
- Sanford-Burnham Medical Research Institute, Orlando, Florida, United States of America
| | - Timothy S. Church
- Pennington Biomedical Research Center, Baton Rouge, Louisiana, United States of America
| | - Eric Ravussin
- Pennington Biomedical Research Center, Baton Rouge, Louisiana, United States of America
- * E-mail:
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Gly482Ser mutation impairs the effects of peroxisome proliferator-activated receptor γ coactivator-1α on decreasing fat deposition and stimulating phosphoenolpyruvate carboxykinase expression in hepatocytes. Nutr Res 2013; 33:332-9. [PMID: 23602251 DOI: 10.1016/j.nutres.2013.02.003] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2012] [Revised: 12/22/2012] [Accepted: 02/05/2013] [Indexed: 12/21/2022]
Abstract
Peroxisome proliferator-activated receptor γ coactivator-1α (PGC-1α) is a transcriptional coactivator of nuclear receptor peroxisome proliferator-activated receptor γ that critically regulates glucose and fat metabolism. Although clinical evidence suggests that Gly482Ser polymorphism of PGC-1α is associated with an increased incidence of nonalcoholic fatty liver disease, a direct role for Gly482Ser mutation in altering PGC-1α actions on hepatocyte fat deposition remains to be explored. We hypothesized that Gly482Ser mutation impairs the abilities of PGC-1α in ameliorating overnutrition-induced hepatocyte fat deposition and in stimulating hepatocyte expression of cytosolic phosphoenolpyruvate carboxykinase (PEPCK-C; encoded by a key PGC-1α target gene). In the present study, treatment of cultured hepatocytes with palmitate induced fat deposition, serving as a cell model of hepatic steatosis. Upon overexpression of wild-type PGC-1α, H4IIE cells exhibited a significant decrease in palmitate-induced hepatocyte fat deposition compared with control cells and/or cells upon overexpression of mutant PGC-1α (Gly482Ser). Overexpression of wild-type PGC-1α, but not mutant PGC-1α, also caused a significant increase in hepatocyte expression of carnitine palmitoyl transferase 1a, a rate-determining enzyme that transfers long-chain fatty acids into mitochondria for oxidation. In addition, overexpression of mutant PGC-1α did not stimulate PEPCK-C expression as overexpression of wild-type PGC-1α did, likely due to a decrease in the ability of mutant PGC-1α in increasing PEPCK promoter transcription activity. Together, these results suggest that Gly482Ser mutation impairs the abilities of PGC-1α in decreasing fat deposition and in stimulating PEPCK-C expression in cultured hepatocytes.
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Quinn LS, Anderson BG, Conner JD, Wolden-Hanson T. IL-15 overexpression promotes endurance, oxidative energy metabolism, and muscle PPARδ, SIRT1, PGC-1α, and PGC-1β expression in male mice. Endocrinology 2013; 154:232-45. [PMID: 23161867 PMCID: PMC3529369 DOI: 10.1210/en.2012-1773] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Endurance exercise initiates a pattern of gene expression that promotes fat oxidation, which in turn improves endurance, body composition, and insulin sensitivity. The signals from exercise that initiate these pathways have not been completely characterized. IL-15 is a cytokine that is up-regulated in skeletal muscle after exercise and correlates with leanness and insulin sensitivity. To determine whether IL-15 can induce any of the metabolic adaptations associated with exercise, substrate metabolism, endurance, and molecular expression patterns were examined in male transgenic mice with constitutively elevated muscle and circulating IL-15 levels. IL-15 transgenic mice ran twice as long as littermate control mice in a run-to-exhaustion trial and preferentially used fat for energy metabolism. Fast muscles in IL-15 transgenic mice exhibited high expression of intracellular mediators of oxidative metabolism that are induced by exercise, including sirtuin 1, peroxisome proliferator-activated receptor (PPAR)-δ, PPAR-γ coactivator-1α, and PPAR-γ coactivator-1β. Muscle tissue in IL-15 transgenic mice exhibited myosin heavy chain and troponin I mRNA isoform expression patterns indicative of a more oxidative phenotype than controls. These findings support a role for IL-15 in induction of exercise endurance, oxidative metabolism, and skeletal muscle molecular adaptations induced by physical training.
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Affiliation(s)
- Lebris S Quinn
- S-182 Geriatric Research, Education, and Clinical Center, VA Puget Sound Health Care System, 1660 South Columbian Way, Seattle, WA 98108, USA.
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Patrick BA, Das A, Jaiswal AK. NAD(P)H:quinone oxidoreductase 1 protects bladder epithelium against painful bladder syndrome in mice. Free Radic Biol Med 2012; 53:1886-93. [PMID: 22985937 PMCID: PMC3495563 DOI: 10.1016/j.freeradbiomed.2012.08.584] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/17/2012] [Revised: 08/23/2012] [Accepted: 08/24/2012] [Indexed: 11/23/2022]
Abstract
Painful bladder syndrome (PBS), or interstitial cystitis, is a poorly understood chronic disease that is characterized by thinning of the bladder epithelium and intense pain. Here we demonstrate that NAD(P)H:quinone oxidoreductase 1(-/-) (NQO1(-/-)) mice developed in our laboratory represent a new animal model of PBS. NQO1 is known to protect against physiological stress as well as protecting transcription factors against proteasomal degradation. In this study we demonstrate that NQO1 is necessary for bladder epithelium integrity and to prevent the development/progression of PBS. We observed downregulation of energy metabolism, adhesion, and apoptotic signaling cascades, which led to mitochondrial aberrations and profound alterations in energy metabolism, increased susceptibility to reactive oxygen species generation, and apoptosis in luminal epithelium in NQO1(-/-) mice that were absent in wild-type mice. These pathophysiological changes led to the incidence of PBS in NQO1(-/-) mice. Altogether, the results demonstrate for the first time that NQO1 is an endogenous factor in protection against PBS.
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Affiliation(s)
- Brad A Patrick
- Department of Pharmacology and Experimental Therapeutics, University of Maryland School of Medicine, Baltimore, MD 21201, USA
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Wang Y, Winters J, Subramaniam S. Functional classification of skeletal muscle networks. I. Normal physiology. J Appl Physiol (1985) 2012; 113:1884-901. [PMID: 23085959 DOI: 10.1152/japplphysiol.01514.2011] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Extensive measurements of the parts list of human skeletal muscle through transcriptomics and other phenotypic assays offer the opportunity to reconstruct detailed functional models. Through integration of vast amounts of data present in databases and extant knowledge of muscle function combined with robust analyses that include a clustering approach, we present both a protein parts list and network models for skeletal muscle function. The model comprises the four key functional family networks that coexist within a functional space; namely, excitation-activation family (forward pathways that transmit a motoneuronal command signal into the spatial volume of the cell and then use Ca(2+) fluxes to bind Ca(2+) to troponin C sites on F-actin filaments, plus transmembrane pumps that maintain transmission capacity); mechanical transmission family (a sophisticated three-dimensional mechanical apparatus that bidirectionally couples the millions of actin-myosin nanomotors with external axial tensile forces at insertion sites); metabolic and bioenergetics family (pathways that supply energy for the skeletal muscle function under widely varying demands and provide for other cellular processes); and signaling-production family (which represents various sensing, signal transduction, and nuclear infrastructure that controls the turn over and structural integrity and regulates the maintenance, regeneration, and remodeling of the muscle). Within each family, we identify subfamilies that function as a unit through analysis of large-scale transcription profiles of muscle and other tissues. This comprehensive network model provides a framework for exploring functional mechanisms of the skeletal muscle in normal and pathophysiology, as well as for quantitative modeling.
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Affiliation(s)
- Yu Wang
- Department of Bioengineering, University of California San Diego, La Jolla, CA92093-0412, USA
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Williams CB, Gurd BJ. Skeletal muscle SIRT1 and the genetics of metabolic health: therapeutic activation by pharmaceuticals and exercise. APPLICATION OF CLINICAL GENETICS 2012; 5:81-91. [PMID: 23776383 PMCID: PMC3681195 DOI: 10.2147/tacg.s31276] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Silent mating type information regulation 2 homolog 1 (SIRT1) is implicated in the control of skeletal muscle mitochondrial content and function through deacetylation of peroxisome proliferator-activated receptor γ coactivator-1α (PGC-1α) and participation in the SIRT1/PGC-1α axis. The SIRT1/PGC-1α axis control of skeletal muscle mitochondrial biogenesis is an important therapeutic target for obesity and obesity-related metabolic dysfunction, as skeletal muscle mitochondrial dysfunction is implicated in the pathogenesis of multiple metabolic diseases. This review will establish the importance of the SIRT1/PGC-1α axis in the control of skeletal muscle mitochondrial biogenesis, and explore possible pharmacological and physiological interventions designed to activate SIRT1 and the SIRT1/PGC-1α axis in order to prevent and/or treat obesity and obesity-related metabolic disease. The current evidence supports a role for therapeutic activation of SIRT1 and the SIRT1/PGC-1α axis by both pharmaceuticals and exercise in the treatment and prevention of metabolic disease. Future research should be directed toward the feasibility of pharmaceutical activation of SIRT1 in humans and refining exercise prescriptions for optimal SIRT1 activation.
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Affiliation(s)
- Cameron B Williams
- School of Kinesiology and Health Studies, Queen's University, Kingston, Ontario, Canada
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Rinnankoski-Tuikka R, Silvennoinen M, Torvinen S, Hulmi JJ, Lehti M, Kivelä R, Reunanen H, Kainulainen H. Effects of high-fat diet and physical activity on pyruvate dehydrogenase kinase-4 in mouse skeletal muscle. Nutr Metab (Lond) 2012; 9:53. [PMID: 22682013 PMCID: PMC3407034 DOI: 10.1186/1743-7075-9-53] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2012] [Accepted: 06/09/2012] [Indexed: 01/19/2023] Open
Abstract
Background The expression of PDK4 is elevated by diabetes, fasting and other conditions associated with the switch from the utilization of glucose to fatty acids as an energy source. It is previously shown that peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α), a master regulator of energy metabolism, coactivates in cell lines pyruvate dehydrogenase kinase-4 (PDK4) gene expression via the estrogen-related receptor α (ERRα). We investigated the effects of long-term high-fat diet and physical activity on the expression of PDK4, PGC-1α and ERRα and the amount and function of mitochondria in skeletal muscle. Methods Insulin resistance was induced by a high-fat (HF) diet for 19 weeks in C57BL/6 J mice, which were either sedentary or with access to running wheels. The skeletal muscle expression levels of PDK4, PGC-1α and ERRα were measured and the quality and quantity of mitochondrial function was assessed. Results The HF mice were more insulin-resistant than the low-fat (LF) -fed mice. Upregulation of PDK4 and ERRα mRNA and protein levels were seen after the HF diet, and when combined with running even more profound effects on the mRNA expression levels were observed. Chronic HF feeding and voluntary running did not have significant effects on PGC-1α mRNA or protein levels. No remarkable difference was found in the amount or function of mitochondria. Conclusions Our results support the view that insulin resistance is not mediated by the decreased qualitative or quantitative properties of mitochondria. Instead, the role of PDK4 should be contemplated as a possible contributor to high-fat diet-induced insulin resistance.
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Affiliation(s)
- Rita Rinnankoski-Tuikka
- Neuromuscular Research Center, Department of Biology of Physical Activity, University of Jyväskylä, Jyväskylä, Finland.
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Michel S, Wanet A, De Pauw A, Rommelaere G, Arnould T, Renard P. Crosstalk between mitochondrial (dys)function and mitochondrial abundance. J Cell Physiol 2012; 227:2297-310. [PMID: 21928343 DOI: 10.1002/jcp.23021] [Citation(s) in RCA: 94] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
A controlled regulation of mitochondrial mass through either the production (biogenesis) or the degradation (mitochondrial quality control) of the organelle represents a crucial step for proper mitochondrial and cell function. Key steps of mitochondrial biogenesis and quality control are overviewed, with an emphasis on the role of mitochondrial chaperones and proteases that keep mitochondria fully functional, provided the mitochondrial activity impairment is not excessive. In this case, the whole organelle is degraded by mitochondrial autophagy or "mitophagy." Beside the maintenance of adequate mitochondrial abundance and functions for cell homeostasis, mitochondrial biogenesis might be enhanced, through discussed signaling pathways, in response to various physiological stimuli, like contractile activity, exposure to low temperatures, caloric restriction, and stem cells differentiation. In addition, mitochondrial dysfunction might also initiate a retrograde response, enabling cell adaptation through increased mitochondrial biogenesis.
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Affiliation(s)
- Sébastien Michel
- Laboratory of Biochemistry and Cell Biology (URBC), NARILIS (Namur Research Institute for Life Sciences), University of Namur (FUNDP), Namur, Belgium
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Wenz T, Wang X, Marini M, Moraes CT. A metabolic shift induced by a PPAR panagonist markedly reduces the effects of pathogenic mitochondrial tRNA mutations. J Cell Mol Med 2012; 15:2317-25. [PMID: 21129152 PMCID: PMC3361135 DOI: 10.1111/j.1582-4934.2010.01223.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Mutations in mitochondrial DNA-encoded tRNA genes are associated with many human diseases. Activation of peroxisome proliferator-activated receptors (PPARs) by synthetic agonists stimulates oxidative metabolism, induces an increase in mitochondrial mass and partially compensates for oxidative phosphorylation system (OXPHOS) defects caused by single OXPHOS enzyme deficiencies in vitro and in vivo. Here, we analysed whether treatment with the PPAR panagonist bezafibrate in cybrids homoplasmic for different mitochondrial tRNA mutations could ameliorate the OXPHOS defect. We found that bezafibrate treatment increased mitochondrial mass, mitochondrial tRNA steady state levels and enhanced mitochondrial protein synthesis. This improvement resulted in increased OXPHOS activity and finally in enhanced mitochondrial ATP generating capacity. PPAR panagonists are known to increase the expression of PPAR gamma coactivator-1α (PGC-1α), a master regulator of mitochondrial biogenesis. Accordingly, we found that clones of a line harbouring a mutated mitochondrial tRNA gene mutation selected for the ability to grow in a medium selective for OXPHOS function had a 3-fold increase in PGC-1α expression, an increase that was similar to the one observed after bezafibrate treatment. These findings show that increasing mitochondrial mass and thereby boosting residual OXPHOS capacity can be beneficial to an important class of mitochondrial defects reinforcing the potential therapeutic use of approaches stimulating mitochondrial proliferation for mitochondrial disorders.
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Affiliation(s)
- Tina Wenz
- Department of Neurology, University of Miami School of Medicine, Miami, FL 33136, USA
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Donges CE, Burd NA, Duffield R, Smith GC, West DWD, Short MJ, Mackenzie R, Plank LD, Shepherd PR, Phillips SM, Edge JA. Concurrent resistance and aerobic exercise stimulates both myofibrillar and mitochondrial protein synthesis in sedentary middle-aged men. J Appl Physiol (1985) 2012; 112:1992-2001. [PMID: 22492939 DOI: 10.1152/japplphysiol.00166.2012] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
We determined myofibrillar and mitochondrial protein fractional synthesis rates (FSR), intramuscular signaling protein phosphorylation, and mRNA expression responses after isolated bouts of resistance exercise (RE), aerobic exercise (AE), or in combination [termed concurrent exercise (CE)] in sedentary middle-aged men. Eight subjects (age = 53.3 ± 1.8 yr; body mass index = 29.4 ± 1.4 kg·m(2)) randomly completed 8 × 8 leg extension repetitions at 70% of one repetition-maximum, 40 min of cycling at 55% peak aerobic power output (AE), or (consecutively) 50% of the RE and AE trials (CE). Biopsies were obtained (during a primed, constant infusion of l-[ring-(13)C(6)]phenylalanine) while fasted, and at 1 and 4 h following postexercise ingestion of 20 g of protein. All trials increased mitochondrial FSR above fasted rates (RE = 1.3-fold; AE = 1.5; CE = 1.4; P < 0.05), although only CE (2.2) and RE (1.8) increased myofibrillar FSR (P < 0.05). At 1 h postexercise, phosphorylation of Akt on Ser(473) (CE = 7.7; RE = 4.6) and Thr(308) (CE = 4.4; RE = 2.9), and PRAS40 on Thr(246) (CE = 3.8; AE = 2.5) increased (P < 0.05), with CE greater than AE for Akt Ser(473)-Thr(308) and greater than RE for PRAS40 (P < 0.05). Despite increased phosphorylation of Akt-PRAS40, phosphorylation of mammalian target of rapamycin (Ser(2448)) remained unchanged (P > 0.05), while rpS6 (Ser(235/236)) increased only in RE (10.4) (P < 0.05). CE and AE both resulted in increased peroxisome proliferator receptor-γ coactivator 1-α (PGC1α) expression at 1 h (CE = 2.9; AE = 2.8; P < 0.05) and 4 h (CE = 2.6; AE = 2.4) and PGC1β expression at 4 h (CE = 2.1; AE = 2.6; P < 0.05). These data suggest that CE-induced acute stimulation of myofibrillar and mitochondrial FSR, protein signaling, and mRNA expression are equivalent to either isolate mode (RE or AE). These results occurred without an interference effect on muscle protein subfractional synthesis rates, protein signaling, or mRNA expression.
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Affiliation(s)
- Cheyne E Donges
- School of Human Movement Studies, Charles Sturt University, Bathurst, New South Wales, Australia
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Machado MV, Ferreira DMS, Castro RE, Silvestre AR, Evangelista T, Coutinho J, Carepa F, Costa A, Rodrigues CMP, Cortez-Pinto H. Liver and muscle in morbid obesity: the interplay of fatty liver and insulin resistance. PLoS One 2012; 7:e31738. [PMID: 22359625 PMCID: PMC3281005 DOI: 10.1371/journal.pone.0031738] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2011] [Accepted: 01/12/2012] [Indexed: 01/07/2023] Open
Abstract
INTRODUCTION Nonalcoholic fatty liver disease (NAFLD) can be seen as a manifestation of overnutrition. The muscle is a central player in the adaptation to energy overload, and there is an association between fatty-muscle and -liver. We aimed to correlate muscle morphology, mitochondrial function and insulin signaling with NAFLD severity in morbid obese patients. METHODS Liver and deltoid muscle biopsies were collected during bariatric surgery in NAFLD patients. NAFLD Activity Score and Younossi's classification for nonalcoholic steatohepatitis (NASH) were applied to liver histology. Muscle evaluation included morphology studies, respiratory chain complex I to IV enzyme assays, and analysis of the insulin signaling cascade. A healthy lean control group was included for muscle morphology and mitochondrial function analyses. RESULTS Fifty one NAFLD patients were included of whom 43% had NASH. Intramyocellular lipids (IMCL) were associated with the presence of NASH (OR 12.5, p<0.001), progressive hepatic inflammation (p = 0.029) and fibrosis severity (p = 0.010). There was a trend to an association between IMCL and decreased Akt phosphorylation (p = 0.059), despite no association with insulin resistance. In turn, hepatic steatosis (p = 0.015) and inflammation (p = 0.013) were associated with decreased Akt phosphoryation. Citrate synthase activity was lower in obese patients (p = 0.047) whereas complex I (p = 0.040) and III (p = 0.036) activities were higher, compared with controls. Finally, in obese patients, complex I activity increased with progressive steatosis (p = 0.049) and with a trend with fibrosis severity (p = 0.056). CONCLUSIONS In morbid obese patients, presence of IMCL associates with NASH and advanced fibrosis. Muscle mitochondrial dysfunction does not appear to be a major driving force contributing to muscle fat accumulation, insulin resistance or liver disease. Importantly, insulin resistance in muscle might occur at a late point in the insulin signaling cascade and be associated with IMCL and NAFLD severity.
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Affiliation(s)
- Mariana Verdelho Machado
- Departamento de Gastrenterologia, Unidade de Nutrição e Metabolismo, Hospital Santa Maria, Faculdade de Medicina de Lisboa, IMM, Lisbon, Portugal
| | - Duarte M. S. Ferreira
- Research Institute for Medicines and Pharmaceutical Sciences (iMed.UL), Faculty of Pharmacy, University of Lisbon, Lisbon, Portugal
| | - Rui E. Castro
- Research Institute for Medicines and Pharmaceutical Sciences (iMed.UL), Faculty of Pharmacy, University of Lisbon, Lisbon, Portugal
| | | | | | - João Coutinho
- Departamento de Cirurgia, Hospital Santa Maria, Lisbon, Portugal
| | - Fátima Carepa
- Departamento de Cirurgia, Hospital Santa Maria, Lisbon, Portugal
| | - Adília Costa
- Departamento de Anatomia Patológica, Hospital Santa Maria, Lisbon, Portugal
| | - Cecília M. P. Rodrigues
- Research Institute for Medicines and Pharmaceutical Sciences (iMed.UL), Faculty of Pharmacy, University of Lisbon, Lisbon, Portugal
| | - Helena Cortez-Pinto
- Departamento de Gastrenterologia, Unidade de Nutrição e Metabolismo, Hospital Santa Maria, Faculdade de Medicina de Lisboa, IMM, Lisbon, Portugal
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Wang L, Mascher H, Psilander N, Blomstrand E, Sahlin K. Resistance exercise enhances the molecular signaling of mitochondrial biogenesis induced by endurance exercise in human skeletal muscle. J Appl Physiol (1985) 2011; 111:1335-44. [PMID: 21836044 DOI: 10.1152/japplphysiol.00086.2011] [Citation(s) in RCA: 111] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Combining endurance and strength training (concurrent training) may change the adaptation compared with single mode training. However, the site of interaction and the mechanisms are unclear. We have investigated the hypothesis that molecular signaling of mitochondrial biogenesis after endurance exercise is impaired by resistance exercise. Ten healthy subjects performed either only endurance exercise (E; 1-h cycling at ∼65% of maximal oxygen uptake), or endurance exercise followed by resistance exercise (ER; 1-h cycling + 6 sets of leg press at 70–80% of 1 repetition maximum) in a randomized cross-over design. Muscle biopsies were obtained before and after exercise (1 and 3 h postcycling). The mRNA of genes related to mitochondrial biogenesis [(peroxisome proliferator-activated receptor-γ coactivator-1 (PGC-1)α, PGC-1-related coactivator (PRC)] related coactivator) and substrate regulation (pyruvate dehydrogenase kinase-4) increased after both E and ER, but the mRNA levels were about twofold higher after ER ( P < 0.01). Phosphorylation of proteins involved in the signaling cascade of protein synthesis [mammalian target of rapamycin (mTOR), ribosomal S6 kinase 1, and eukaryotic elongation factor 2] was altered after ER but not after E. Moreover, ER induced a larger increase in mRNA of genes associated with positive mTOR signaling (cMyc and Rheb). Phosphorylation of AMP-activated protein kinase, acetyl-CoA carboxylase, and Akt increased similarly at 1 h postcycling ( P < 0.01) after both types of exercise. Contrary to our hypothesis, the results demonstrate that ER, performed after E, amplifies the adaptive signaling response of mitochondrial biogenesis compared with single-mode endurance exercise. The mechanism may relate to a cross talk between signaling pathways mediated by mTOR. The results suggest that concurrent training may be beneficial for the adaptation of muscle oxidative capacity.
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Affiliation(s)
- Li Wang
- The Åstrand Laboratory of Work Physiology, GIH, the Swedish School of Sport and Health Sciences, and
| | - Henrik Mascher
- The Åstrand Laboratory of Work Physiology, GIH, the Swedish School of Sport and Health Sciences, and
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - Niklas Psilander
- The Åstrand Laboratory of Work Physiology, GIH, the Swedish School of Sport and Health Sciences, and
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - Eva Blomstrand
- The Åstrand Laboratory of Work Physiology, GIH, the Swedish School of Sport and Health Sciences, and
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - Kent Sahlin
- The Åstrand Laboratory of Work Physiology, GIH, the Swedish School of Sport and Health Sciences, and
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
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Roestenberg P, Manjeri GR, Valsecchi F, Smeitink JAM, Willems PHGM, Koopman WJH. Pharmacological targeting of mitochondrial complex I deficiency: the cellular level and beyond. Mitochondrion 2011; 12:57-65. [PMID: 21757032 DOI: 10.1016/j.mito.2011.06.011] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2010] [Revised: 01/20/2011] [Accepted: 06/25/2011] [Indexed: 12/20/2022]
Abstract
Complex I (CI) represents a major entry point of electrons in the mitochondrial electron transport chain (ETC). It consists of 45 different subunits, encoded by the mitochondrial (mtDNA) and nuclear DNA (nDNA). In humans, mutations in nDNA-encoded subunits cause severe neurodegenerative disorders like Leigh Syndrome with onset in early childhood. The pathophysiological mechanism of these disorders is still poorly understood. Here we summarize the current knowledge concerning the consequences of nDNA-encoded CI mutations in patient-derived cells, present mouse models for human CI deficiency, and discuss potential treatment strategies for CI deficiency.
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Affiliation(s)
- Peggy Roestenberg
- Department of Biochemistry, Nijmegen Centre for Molecular Life Sciences, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
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microRNA-122 as a regulator of mitochondrial metabolic gene network in hepatocellular carcinoma. Mol Syst Biol 2011; 6:402. [PMID: 20739924 PMCID: PMC2950084 DOI: 10.1038/msb.2010.58] [Citation(s) in RCA: 154] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2009] [Accepted: 06/29/2010] [Indexed: 02/06/2023] Open
Abstract
A moderate loss of miR-122 function correlates with up-regulation of seed-matched genes and down-regulation of mitochondrially localized genes in both human hepatocellular carcinoma and in normal mice treated with anti-miR-122 antagomir. Putative direct targets up-regulated with loss of miR-122 and secondary targets down-regulated with loss of miR-122 are conserved between human beings and mice and are rapidly regulated in vitro in response to miR-122 over- and under-expression. Loss of miR-122 secondary target expression in either tumorous or adjacent non-tumorous tissue predicts poor survival of heptatocellular carcinoma patients.
Hepatocellular carcinoma (HCC) is one of the most aggressive human malignancies, common in Asia, Africa, and in areas with endemic infections of hepatitis-B or -C viruses (HBV or HCV) (But et al, 2008). Globally, the 5-year survival rate of HCC is <5% and about 600 000 HCC patients die each year. The high mortality associated with this disease is mainly attributed to the failure to diagnose HCC patients at an early stage and a lack of effective therapies for patients with advanced stage HCC. Understanding the relationships between phenotypic and molecular changes in HCC is, therefore, of paramount importance for the development of improved HCC diagnosis and treatment methods. In this study, we examined mRNA and microRNA (miRNA)-expression profiles of tumor and adjacent non-tumor liver tissue from HCC patients. The patient population was selected from a region of endemic HBV infection, and HBV infection appears to contribute to the etiology of HCC in these patients. A total of 96 HCC patients were included in the study, of which about 88% tested positive for HBV antigen; patients testing positive for HCV antigen were excluded. Among the 220 miRNAs profiled, miR-122 was the most highly expressed miRNA in liver, and its expression was decreased almost two-fold in HCC tissue relative to adjacent non-tumor tissue, confirming earlier observations (Lagos-Quintana et al, 2002; Kutay et al, 2006; Budhu et al, 2008). Over 1000 transcripts were correlated and over 1000 transcripts were anti-correlated with miR-122 expression. Consistent with the idea that transcripts anti-correlated with miR-122 are potential miR-122 targets, the most highly anti-correlated transcripts were highly enriched for the presence of the miR-122 central seed hexamer, CACTCC, in the 3′UTR. Although the complete set of negatively correlated genes was enriched for cell-cycle genes, the subset of seed-matched genes had no significant KEGG Pathway annotation, suggesting that miR-122 is unlikely to directly regulate the cell cycle in these patients. In contrast, transcripts positively correlated with miR-122 were not enriched for 3′UTR seed matches to miR-122. Interestingly, these 1042 transcripts were enriched for genes coding for mitochondrially localized proteins and for metabolic functions. To analyze the impact of loss of miR-122 in vivo, silencing of miR-122 was performed by antisense inhibition (anti-miR-122) in wild-type mice (Figure 3). As with the genes negatively correlated with miR-122 in HCC patients, no significant biological annotation was associated with the seed-matched genes up-regulated by anti-miR-122 in mouse livers. The most significantly enriched biological annotation for anti-miR-122 down-regulated genes, as for positively correlated genes in HCC, was mitochondrial localization; the down-regulated mitochondrial genes were enriched for metabolic functions. Putative direct and downstream targets with orthologs on both the human and mouse microarrays showed significant overlap for regulations in the same direction. These overlaps defined sets of putative miR-122 primary and secondary targets. The results were further extended in the analysis of a separate dataset from 180 HCC, 40 cirrhotic, and 6 normal liver tissue samples (Figure 4), showing anti-correlation of proposed primary and secondary targets in non-healthy tissues. To validate the direct correlation between miR-122 and some of the primary and secondary targets, we determined the expression of putative targets after transfection of miR-122 mimetic into PLC/PRF/5 HCC cells, including the putative direct targets SMARCD1 and MAP3K3 (MEKK3), a target described in the literature, CAT-1 (SLC7A1), and three putative secondary targets, PPARGC1A (PGC-1α) and succinate dehydrogenase subunits A and B. As expected, the putative direct targets showed reduced expression, whereas the putative secondary target genes showed increased expression in cells over-expressing miR-122 (Figure 4). Functional classification of genes using the total ancestry method (Yu et al, 2007) identified PPARGC1A (PGC-1α) as the most connected secondary target. PPARGC1A has been proposed to function as a master regulator of mitochondrial biogenesis (Ventura-Clapier et al, 2008), suggesting that loss of PPARGC1A expression may contribute to the loss of mitochondrial gene expression correlated with loss of miR-122 expression. To further validate the link of miR-122 and PGC-1α protein, we transfected PLC/PRF/5 cells with miR-122-expression vector, and observed an increase in PGC-1α protein levels. Importantly, transfection of both miR-122 mimetic and miR-122-expression vector significantly reduced the lactate content of PLC/PRF/5 cells, whereas anti-miR-122 treatment increased lactate production. Together, the data support the function of miR-122 in mitochondrial metabolic functions. Patient survival was not directly associated with miR-122-expression levels. However, miR-122 secondary targets were expressed at significantly higher levels in both tumor and adjacent non-tumor tissues among survivors as compared with deceased patients, providing supporting evidence for the potential relevance of loss of miR-122 function in HCC patient morbidity and mortality. Overall, our findings reveal potentially new biological functions for miR-122 in liver physiology. We observed decreased expression of miR-122, a liver-specific miRNA, in HBV-associated HCC, and loss of miR-122 seemed to correlate with the decrease of mitochondrion-related metabolic pathway gene expression in HCC and in non-tumor liver tissues, a result that is consistent with the outcome of treatment of mice with anti-miR-122 and is of prognostic significance for HCC patients. Further investigation will be conducted to dissect the regulatory function of miR-122 on mitochondrial metabolism in HCC and to test whether increasing miR-122 expression can improve mitochondrial function in liver and perhaps in liver tumor tissues. Moreover, these results support the idea that primary targets of a given miRNA may be distributed over a variety of functional categories while resulting in a coordinated secondary response, potentially through synergistic action (Linsley et al, 2007). Tumorigenesis involves multistep genetic alterations. To elucidate the microRNA (miRNA)–gene interaction network in carcinogenesis, we examined their genome-wide expression profiles in 96 pairs of tumor/non-tumor tissues from hepatocellular carcinoma (HCC). Comprehensive analysis of the coordinate expression of miRNAs and mRNAs reveals that miR-122 is under-expressed in HCC and that increased expression of miR-122 seed-matched genes leads to a loss of mitochondrial metabolic function. Furthermore, the miR-122 secondary targets, which decrease in expression, are good prognostic markers for HCC. Transcriptome profiling data from additional 180 HCC and 40 liver cirrhotic patients in the same cohort were used to confirm the anti-correlation of miR-122 primary and secondary target gene sets. The HCC findings can be recapitulated in mouse liver by silencing miR-122 with antagomir treatment followed by gene-expression microarray analysis. In vitro miR-122 data further provided a direct link between induction of miR-122-controlled genes and impairment of mitochondrial metabolism. In conclusion, miR-122 regulates mitochondrial metabolism and its loss may be detrimental to sustaining critical liver function and contribute to morbidity and mortality of liver cancer patients.
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Li L, Hossain MA, Sadat S, Hager L, Liu L, Tam L, Schroer S, Huogen L, Fantus IG, Connelly PW, Woo M, Ng DS. Lecithin cholesterol acyltransferase null mice are protected from diet-induced obesity and insulin resistance in a gender-specific manner through multiple pathways. J Biol Chem 2011; 286:17809-20. [PMID: 21454561 DOI: 10.1074/jbc.m110.180893] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Complete lecithin cholesterol acyltransferase (LCAT) deficiency uniformly results in a profound HDL deficiency. We recently reported unexpected enhanced insulin sensitivity in LCAT knock-out mice in the LDL receptor knock-out background (Ldlr(-/-)×Lcat(-/-); double knock-out (DKO)), when compared with their Ldlr(-/-)×Lcat(+/+) (single knock-out (SKO)) controls. Here, we report that LCAT-deficient mice (DKO and Lcat(-/-)) are protected against high fat high sucrose (HFHS) diet-induced obesity without hypophagia in a gender-specific manner compared with their respective (SKO and WT) controls. The metabolic phenotypes are more pronounced in the females. Changes in endoplasmic reticulum stress were examined as a possible mechanism for the metabolic protection. The female DKO mice developed attenuated HFHS-induced endoplasmic reticulum stress as evidenced by a lack of increase in mRNA levels of the hepatic unfolded protein response (UPR) markers Grp78 and CHOP compared with SKO controls. The DKO female mice were also protected against diet-induced insulin resistance. In white adipose tissue of chow-fed DKO mice, we also observed a reduction in UPR, gene markers for adipogenesis, and markers for activation of Wnt signaling. In skeletal muscles of female DKO mice, we observed an unexpected increase in UCP1 in association with increase in phospho-AMPKα, PGC1α, and UCP3 expressions. This increase in UCP1 was associated with ectopic islands of brown adipocytes between skeletal muscle fibers. Our findings suggest that LCAT deficiency confers gender-specific protection against diet-induced obesity and insulin resistance at least in part through regulation in UPR, white adipose tissue adipogenesis, and brown adipocyte partitioning.
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Affiliation(s)
- Lixin Li
- Keenan Research Centre, Li Ka Shing Knowledge Institute, Department of Medicine, St. Michael's Hospital, Toronto M5B 1W8, Canada
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Frazier EP, Isenberg JS, Shiva S, Zhao L, Schlesinger P, Dimitry J, Abu-Asab MS, Tsokos M, Roberts DD, Frazier WA. Age-dependent regulation of skeletal muscle mitochondria by the thrombospondin-1 receptor CD47. Matrix Biol 2011; 30:154-61. [PMID: 21256215 DOI: 10.1016/j.matbio.2010.12.004] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2010] [Revised: 12/15/2010] [Accepted: 12/16/2010] [Indexed: 02/08/2023]
Abstract
CD47, a receptor for thrombospondin-1, limits two important regulatory axes: nitric oxide-cGMP signaling and cAMP signaling, both of which can promote mitochondrial biogenesis. Electron microscopy revealed increased mitochondrial densities in skeletal muscle from both CD47 null and thrombospondin-1 null mice. We further assessed the mitochondria status of CD47-null vs WT mice. Quantitative RT-PCR of RNA extracted from tissues of 3 month old mice revealed dramatically elevated expression of mRNAs encoding mitochondrial proteins and PGC-1α in both fast and slow-twitch skeletal muscle from CD47-null mice, but modest to no elevation in other tissues. These observations were confirmed by Western blotting of mitochondrial proteins. Relative amounts of electron transport enzymes and ATP/O(2) ratios of isolated mitochondria were not different between mitochondria from CD47-null and WT cells. Young CD47-null mice displayed enhanced treadmill endurance relative to WTs and CD47-null gastrocnemius had undergone fiber type switching to a slow-twitch pattern of myoglobin and myosin heavy chain expression. In 12 month old mice, both skeletal muscle mitochondrial volume density and endurance had decreased to wild type levels. Expression of myosin heavy chain isoforms and myoglobin also reverted to a fast twitch pattern in gastrocnemius. Both CD47 and TSP1 null mice are leaner than WTs, use less oxygen and produce less heat than WT mice. CD47-null cells produce substantially less reactive oxygen species than WT cells. These data indicate that loss of signaling from the TSP1-CD47 system promotes accumulation of normally functioning mitochondria in a tissue-specific and age-dependent fashion leading to enhanced physical performance, lower reactive oxygen species production and more efficient metabolism.
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Affiliation(s)
- Elfaridah P Frazier
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, MO 63110, United States
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Wenz T, Williams SL, Bacman SR, Moraes CT. Emerging therapeutic approaches to mitochondrial diseases. ACTA ACUST UNITED AC 2011; 16:219-29. [PMID: 20818736 DOI: 10.1002/ddrr.109] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Mitochondrial diseases are very heterogeneous and can affect different tissues and organs. Moreover, they can be caused by genetic defects in either nuclear or mitochondrial DNA as well as by environmental factors. All of these factors have made the development of therapies difficult. In this review article, we will discuss emerging approaches to the therapy of mitochondrial disorders, some of which are targeted to specific conditions whereas others may be applicable to a more diverse group of patients.
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Affiliation(s)
- Tina Wenz
- Department of Neurology, University of Miami School of Medicine, 1095 NW 14th Terrace, Miami, FL 33136, USA
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Rosell M, Jones MC, Parker MG. Role of nuclear receptor corepressor RIP140 in metabolic syndrome. Biochim Biophys Acta Mol Basis Dis 2010; 1812:919-28. [PMID: 21193034 PMCID: PMC3117993 DOI: 10.1016/j.bbadis.2010.12.016] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2010] [Revised: 12/15/2010] [Accepted: 12/17/2010] [Indexed: 01/04/2023]
Abstract
Obesity and its associated complications, which can lead to the development of metabolic syndrome, are a worldwide major public health concern especially in developed countries where they have a very high prevalence. RIP140 is a nuclear coregulator with a pivotal role in controlling lipid and glucose metabolism. Genetically manipulated mice devoid of RIP140 are lean with increased oxygen consumption and are resistant to high-fat diet-induced obesity and hepatic steatosis with improved insulin sensitivity. Moreover, white adipocytes with targeted disruption of RIP140 express genes characteristic of brown fat including CIDEA and UCP1 while skeletal muscles show a shift in fibre type composition enriched in more oxidative fibres. Thus, RIP140 is a potential therapeutic target in metabolic disorders. In this article we will review the role of RIP140 in tissues relevant to the appearance and progression of the metabolic syndrome and discuss how the manipulation of RIP140 levels or activity might represent a therapeutic approach to combat obesity and associated metabolic disorders. This article is part of a Special Issue entitled: Translating nuclear receptors from health to disease.
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Affiliation(s)
- Meritxell Rosell
- Institute of Reproductive and Developmental Biology, Imperial College London, Faculty of Medicine, Hammersmith Campus 158 Du Cane Road, W12 0NN, UK.
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Seebacher F, Brand MD, Else PL, Guderley H, Hulbert AJ, Moyes CD. Plasticity of oxidative metabolism in variable climates: molecular mechanisms. Physiol Biochem Zool 2010; 83:721-32. [PMID: 20586603 DOI: 10.1086/649964] [Citation(s) in RCA: 83] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Converting food to chemical energy (ATP) that is usable by cells is a principal requirement to sustain life. The rate of ATP production has to be sufficient for housekeeping functions, such as protein synthesis and maintaining membrane potentials, as well as for growth and locomotion. Energy metabolism is temperature sensitive, and animals respond to environmental variability at different temporal levels, from within-individual to evolutionary timescales. Here we review principal molecular mechanisms that underlie control of oxidative ATP production in response to climate variability. Nuclear transcription factors and coactivators control expression of mitochondrial proteins and abundance of mitochondria. Fatty acid and phospholipid concentrations of membranes influence the activity of membrane-bound proteins as well as the passive leak of protons across the mitochondrial membrane. Passive proton leak as well as protein-mediated proton leak across the inner mitochondrial membrane determine the efficacy of ATP production but are also instrumental in endothermic heat production and as a defense against reactive oxygen species. Both transcriptional mechanisms and membrane composition interact with environmental temperature and diet, and this interaction between diet and temperature in determining mitochondrial function links the two major environmental variables that are affected by changing climates. The limits to metabolic plasticity could be set by the production of reactive oxygen species leading to cellular damage, limits to substrate availability in mitochondria, and a disproportionally large increase in proton leak over ATP production.
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Affiliation(s)
- Frank Seebacher
- School of Biological Sciences, University of Sydney, Sydney, New South Wales 2006, Australia.
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