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de Jong JCBC, Caspers MPM, Worms N, Keijzer N, Kleemann R, Menke AL, Nieuwenhuizen AG, Keijer J, Verschuren L, van den Hoek AM. Translatability of mouse muscle-aging for humans: the role of sex. GeroScience 2024; 46:3341-3360. [PMID: 38265577 PMCID: PMC11009184 DOI: 10.1007/s11357-024-01082-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2023] [Accepted: 01/11/2024] [Indexed: 01/25/2024] Open
Abstract
Muscle-aging drives sarcopenia and is a major public health issue. Mice are frequently used as a model for human muscle-aging, however, research investigating their translational value is limited. In addition, mechanisms underlying muscle-aging may have sex-specific features in humans, but it is not yet assessed whether these are recapitulated in mice. Here, we studied the effects of aging on a functional, histological and transcriptional level at multiple timepoints in male and female mice (4, 17, 21 and 25 months), with particular emphasis on sex-differences. The effects of natural aging on the transcriptome of quadriceps muscle were compared to humans on pathway level. Significant loss of muscle mass occurred late, at 25 months, in both male (-17%, quadriceps) and female mice (-10%, quadriceps) compared to young control mice. Concomitantly, we found in female, but not male mice, a slower movement speed in the aged groups compared to the young mice (P < 0.001). Consistently, weighted gene co-expression network analysis revealed a stronger association between the aging-related reduction of movement and aging-related changes in muscle transcriptome of female compared to male mice (P < 0.001). In male, but not female mice, major distinctive aging-related changes occurred in the last age group (25 months), which highlights the necessity for careful selection of age using mice as a muscle-aging model. Furthermore, contrasting to humans, more aging-related changes were found in the muscle transcriptome of male mice compared to female mice (4090 vs. 2285 differentially expressed genes at 25 months, respectively). Subsequently, male mice recapitulated more muscle-aging related pathways characteristic for both male and female humans. In conclusion, our data show that sex has a critical effect on the mouse muscle-aging trajectory, although these do not necessarily reflect sex differences observed in the human muscle-aging trajectory.
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Affiliation(s)
- Jelle C B C de Jong
- Department of Metabolic Health Research, The Netherlands Organization for Applied Scientific Research (TNO), Leiden, The Netherlands.
- Human and Animal Physiology, Wageningen University, Wageningen, The Netherlands.
| | - Martien P M Caspers
- Department of Microbiology and Systems Biology, The Netherlands Organization for Applied Scientific Research (TNO), Leiden, The Netherlands
| | - Nicole Worms
- Department of Metabolic Health Research, The Netherlands Organization for Applied Scientific Research (TNO), Leiden, The Netherlands
| | - Nanda Keijzer
- Department of Metabolic Health Research, The Netherlands Organization for Applied Scientific Research (TNO), Leiden, The Netherlands
| | - Robert Kleemann
- Department of Metabolic Health Research, The Netherlands Organization for Applied Scientific Research (TNO), Leiden, The Netherlands
| | - Aswin L Menke
- Department of Metabolic Health Research, The Netherlands Organization for Applied Scientific Research (TNO), Leiden, The Netherlands
| | | | - Jaap Keijer
- Human and Animal Physiology, Wageningen University, Wageningen, The Netherlands
| | - Lars Verschuren
- Department of Microbiology and Systems Biology, The Netherlands Organization for Applied Scientific Research (TNO), Leiden, The Netherlands
| | - Anita M van den Hoek
- Department of Metabolic Health Research, The Netherlands Organization for Applied Scientific Research (TNO), Leiden, The Netherlands
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2
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Fountain WA, Bopp TS, Bene M, Walston JD. Metabolic dysfunction and the development of physical frailty: an aging war of attrition. GeroScience 2024:10.1007/s11357-024-01101-7. [PMID: 38400874 DOI: 10.1007/s11357-024-01101-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2024] [Accepted: 02/13/2024] [Indexed: 02/26/2024] Open
Abstract
The World Health Organization recently declared 2021-2030 the decade of healthy aging. Such emphasis on healthy aging requires an understanding of the biologic challenges aging populations face. Physical frailty is a syndrome of vulnerability that puts a subset of older adults at high risk for adverse health outcomes including functional and cognitive decline, falls, hospitalization, and mortality. The physiology driving physical frailty is complex with age-related biological changes, dysregulated stress response systems, chronic inflammatory pathway activation, and altered energy metabolism all likely contributing. Indeed, a series of recent studies suggests circulating metabolomic distinctions can be made between frail and non-frail older adults. For example, marked restrictions on glycolytic and mitochondrial energy production have been independently observed in frail older adults and collectively appear to yield a reliance on the highly fatigable ATP-phosphocreatine (PCr) energy system. Further, there is evidence that age-associated impairments in the primary ATP generating systems (glycolysis, TCA cycle, electron transport) yield cumulative deficits and fail to adequately support the ATP-PCr system. This in turn may acutely contribute to several major components of the physical frailty phenotype including muscular fatigue, weakness, slow walking speed and, over time, result in low physical activity and accelerate reductions in lean body mass. This review describes specific age-associated metabolic declines and how they can collectively lead to metabolic inflexibility, ATP-PCr reliance, and the development of physical frailty. Further investigation remains necessary to understand the etiology of age-associated metabolic deficits and develop targeted preventive strategies that maintain robust metabolic health in older adults.
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Affiliation(s)
- William A Fountain
- Division of Geriatric Medicine and Gerontology, Johns Hopkins University School of Medicine, Baltimore, MD, 21224, USA
| | - Taylor S Bopp
- Division of Geriatric Medicine and Gerontology, Johns Hopkins University School of Medicine, Baltimore, MD, 21224, USA
| | - Michael Bene
- Division of Geriatric Medicine and Gerontology, Johns Hopkins University School of Medicine, Baltimore, MD, 21224, USA
| | - Jeremy D Walston
- Division of Geriatric Medicine and Gerontology, Johns Hopkins University School of Medicine, Baltimore, MD, 21224, USA.
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3
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Ghazvini S, Uthaman S, Synan L, Lin EC, Sarkar S, Santillan MK, Santillan DA, Bardhan R. Predicting the onset of preeclampsia by longitudinal monitoring of metabolic changes throughout pregnancy with Raman spectroscopy. Bioeng Transl Med 2024; 9:e10595. [PMID: 38193120 PMCID: PMC10771567 DOI: 10.1002/btm2.10595] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2023] [Revised: 07/04/2023] [Accepted: 08/15/2023] [Indexed: 01/10/2024] Open
Abstract
Preeclampsia is a life-threatening pregnancy disorder. Current clinical assays cannot predict the onset of preeclampsia until the late 2nd trimester, which often leads to poor maternal and neonatal outcomes. Here we show that Raman spectroscopy combined with machine learning in pregnant patient plasma enables rapid, highly sensitive maternal metabolome screening that predicts preeclampsia as early as the 1st trimester with >82% accuracy. We identified 12, 15 and 17 statistically significant metabolites in the 1st, 2nd and 3rd trimesters, respectively. Metabolic pathway analysis shows multiple pathways corresponding to amino acids, fatty acids, retinol, and sugars are enriched in the preeclamptic cohort relative to a healthy pregnancy. Leveraging Pearson's correlation analysis, we show for the first time with Raman Spectroscopy that metabolites are associated with several clinical factors, including patients' body mass index, gestational age at delivery, history of preeclampsia, and severity of preeclampsia. We also show that protein quantification alone of proinflammatory cytokines and clinically relevant angiogenic markers are inadequate in identifying at-risk patients. Our findings demonstrate that Raman spectroscopy is a powerful tool that may complement current clinical assays in early diagnosis and in the prognosis of the severity of preeclampsia to ultimately enable comprehensive prenatal care for all patients.
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Affiliation(s)
- Saman Ghazvini
- Department of Chemical and Biological EngineeringIowa State UniversityAmesIowaUSA
- Nanovaccine InstituteIowa State UniversityAmesIowaUSA
| | - Saji Uthaman
- Department of Chemical and Biological EngineeringIowa State UniversityAmesIowaUSA
- Nanovaccine InstituteIowa State UniversityAmesIowaUSA
| | - Lilly Synan
- Department of Chemical and Biological EngineeringIowa State UniversityAmesIowaUSA
- Nanovaccine InstituteIowa State UniversityAmesIowaUSA
| | - Eugene C. Lin
- Department of Chemistry and BiochemistryNational Chung Cheng UniversityChiayiTaiwan
| | - Soumik Sarkar
- Department of Mechanical EngineeringIowa state UniversityAmesIowaUSA
| | - Mark K. Santillan
- Department of Obstetrics and Gynecology, Carver College of MedicineUniversity of Iowa, Hospitals & ClinicsIowa CityIowaUSA
| | - Donna A. Santillan
- Department of Obstetrics and Gynecology, Carver College of MedicineUniversity of Iowa, Hospitals & ClinicsIowa CityIowaUSA
| | - Rizia Bardhan
- Department of Chemical and Biological EngineeringIowa State UniversityAmesIowaUSA
- Nanovaccine InstituteIowa State UniversityAmesIowaUSA
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4
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Song J, Duivenvoorde LPM, Grefte S, Kuda O, Martínez-Ramírez F, van der Stelt I, Mastorakou D, van Schothorst EM, Keijer J. Normobaric hypoxia shows enhanced FOXO1 signaling in obese mouse gastrocnemius muscle linked to metabolism and muscle structure and neuromuscular innervation. Pflugers Arch 2023; 475:1265-1281. [PMID: 37656229 PMCID: PMC10567817 DOI: 10.1007/s00424-023-02854-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2023] [Revised: 08/17/2023] [Accepted: 08/21/2023] [Indexed: 09/02/2023]
Abstract
Skeletal muscle relies on mitochondria for sustainable ATP production, which may be impacted by reduced oxygen availability (hypoxia). Compared with long-term hypoxia, the mechanistic in vivo response to acute hypoxia remains elusive. Therefore, we aimed to provide an integrated description of the Musculus gastrocnemius response to acute hypoxia. Fasted male C57BL/6JOlaHsd mice, fed a 40en% fat diet for six weeks, were exposed to 12% O2 normobaric hypoxia or normoxia (20.9% O2) for six hours (n = 12 per group). Whole-body energy metabolism and the transcriptome response of the M. gastrocnemius were analyzed and confirmed by acylcarnitine determination and Q-PCR. At the whole-body level, six hours of hypoxia reduced energy expenditure, increased blood glucose and tended to decreased the respiratory exchange ratio (RER). Whole-genome transcriptome analysis revealed upregulation of forkhead box-O (FOXO) signalling, including an increased expression of tribbles pseudokinase 3 (Trib3). Trib3 positively correlated with blood glucose levels. Upregulated carnitine palmitoyltransferase 1A negatively correlated with the RER, but the significantly increased in tissue C14-1, C16-0 and C18-1 acylcarnitines supported that β-oxidation was not regulated. The hypoxia-induced FOXO activation could also be connected to altered gene expression related to fiber-type switching, extracellular matrix remodeling, muscle differentiation and neuromuscular junction denervation. Our results suggest that a six-hour exposure of obese mice to 12% O2 normobaric hypoxia impacts M. gastrocnemius via FOXO1, initiating alterations that may contribute to muscle remodeling of which denervation is novel and warrants further investigation. The findings support an early role of hypoxia in tissue alterations in hypoxia-associated conditions such as aging and obesity.
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Affiliation(s)
- Jingyi Song
- Human and Animal Physiology, Wageningen University, Wageningen, The Netherlands
| | | | - Sander Grefte
- Human and Animal Physiology, Wageningen University, Wageningen, The Netherlands
| | - Ondrej Kuda
- Laboratory of Metabolism of Bioactive Lipids, Institute of Physiology, Czech Academy of Sciences, 14220, Prague 4, Czech Republic
| | - Felipe Martínez-Ramírez
- Laboratory of Metabolism of Bioactive Lipids, Institute of Physiology, Czech Academy of Sciences, 14220, Prague 4, Czech Republic
| | - Inge van der Stelt
- Human and Animal Physiology, Wageningen University, Wageningen, The Netherlands
| | - Dimitra Mastorakou
- Laboratory of Metabolism of Bioactive Lipids, Institute of Physiology, Czech Academy of Sciences, 14220, Prague 4, Czech Republic
| | | | - Jaap Keijer
- Human and Animal Physiology, Wageningen University, Wageningen, The Netherlands.
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5
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Nidadavolu LS, Cosarderelioglu C, Merino Gomez A, Wu Y, Bopp T, Zhang C, Nguyen T, Marx-Rattner R, Yang H, Antonescu C, Florea L, Talbot CC, Smith B, Foster DB, Fairman JE, Yenokyan G, Chung T, Le A, Walston JD, Abadir PM. Interleukin-6 Drives Mitochondrial Dysregulation and Accelerates Physical Decline: Insights From an Inducible Humanized IL-6 Knock-In Mouse Model. J Gerontol A Biol Sci Med Sci 2023; 78:1740-1752. [PMID: 37310873 PMCID: PMC10562892 DOI: 10.1093/gerona/glad147] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2023] [Indexed: 06/15/2023] Open
Abstract
Chronic activation of inflammatory pathways (CI) and mitochondrial dysfunction are independently linked to age-related functional decline and early mortality. Interleukin 6 (IL-6) is among the most consistently elevated chronic activation of inflammatory pathways markers, but whether IL-6 plays a causative role in this mitochondrial dysfunction and physical deterioration remains unclear. To characterize the role of IL-6 in age-related mitochondrial dysregulation and physical decline, we have developed an inducible human IL-6 (hIL-6) knock-in mouse (TetO-hIL-6mitoQC) that also contains a mitochondrial-quality control reporter. Six weeks of hIL-6 induction resulted in upregulation of proinflammatory markers, cell proliferation and metabolic pathways, and dysregulated energy utilization. Decreased grip strength, increased falls off the treadmill, and increased frailty index were also observed. Further characterization of skeletal muscles postinduction revealed an increase in mitophagy, downregulation of mitochondrial biogenesis genes, and an overall decrease in total mitochondrial numbers. This study highlights the contribution of IL-6 to mitochondrial dysregulation and supports a causal role of hIL-6 in physical decline and frailty.
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Affiliation(s)
- Lolita S Nidadavolu
- Division of Geriatrics and Gerontology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Caglar Cosarderelioglu
- Division of Geriatrics and Gerontology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Alessandra Merino Gomez
- Division of Geriatrics and Gerontology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Yuqiong Wu
- Division of Geriatrics and Gerontology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Taylor Bopp
- Department of Physical Medicine and Rehabilitation, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Cissy Zhang
- Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Tu Nguyen
- Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Ruth Marx-Rattner
- Division of Geriatrics and Gerontology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Huanle Yang
- Division of Geriatrics and Gerontology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Corina Antonescu
- Department of Genetic Medicine, John Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Liliana Florea
- Department of Genetic Medicine, John Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Conover C Talbot
- Institute for Basic Biomedical Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Barbara Smith
- Department of Cell Biology, Imaging Facility, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - D Brian Foster
- Division of Cardiology, Department of Medicine, Johns Hopkins University, Baltimore, Maryland, USA
| | - Jennifer E Fairman
- Division of Cellular and Molecular Medicine, Department of Art as Applied to Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Gayane Yenokyan
- Johns Hopkins Biostatistics Center, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, USA
| | - Tae Chung
- Department of Physical Medicine and Rehabilitation, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Anne Le
- Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Jeremy D Walston
- Division of Geriatrics and Gerontology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Peter M Abadir
- Division of Geriatrics and Gerontology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
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Tian Q, Mitchell BA, Erus G, Davatzikos C, Moaddel R, Resnick SM, Ferrucci L. Sex differences in plasma lipid profiles of accelerated brain aging. Neurobiol Aging 2023; 129:178-184. [PMID: 37336172 PMCID: PMC10527719 DOI: 10.1016/j.neurobiolaging.2023.05.013] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2022] [Revised: 05/18/2023] [Accepted: 05/23/2023] [Indexed: 06/21/2023]
Abstract
Lipids are essential components of brain structure and shown to affect brain function. Previous studies have shown that aging men undergo greater brain atrophy than women, but whether the associations between lipids and brain atrophy differ by sex is unclear. We examined sex differences in the associations between circulating lipids by liquid chromatography-tandem mass spectrometry and the progression of MRI-derived brain atrophy index Spatial Patterns of Atrophy for Recognition of Brain Aging (SPARE-BA) over an average of 4.7 (SD = 2.3) years in 214 men and 261 women aged 60 or older who were initially cognitively normal using multivariable linear regression, adjusted for age, race, education, and baseline SPARE-BA. We found significant sex interactions for beta-oxidation rate, short-chain acylcarnitines, long-chain ceramides, and very long-chain triglycerides. Lower beta-oxidation rate and short-chain acylcarnitines in women and higher long-chain ceramides and very long-chain triglycerides in men were associated with faster increases in SPARE-BA (accelerated brain aging). Circulating lipid profiles of accelerated brain aging are sex-specific and vary by lipid classes and structure. Mechanisms underlying these sex-specific lipid profiles of brain aging warrant further investigation.
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Affiliation(s)
- Qu Tian
- Longitudinal Studies Section, Translational Gerontology Branch, National Institute on Aging, Baltimore, MD, USA.
| | - Brendan A Mitchell
- Longitudinal Studies Section, Translational Gerontology Branch, National Institute on Aging, Baltimore, MD, USA
| | - Guray Erus
- Radiology Department, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Christos Davatzikos
- Radiology Department, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Ruin Moaddel
- Laboratory of Clinical Investigation, National Institute on Aging, Baltimore, MD, USA
| | - Susan M Resnick
- Laboratory of Behavioral Neuroscience, National Institute on Aging, Baltimore, MD, USA
| | - Luigi Ferrucci
- Longitudinal Studies Section, Translational Gerontology Branch, National Institute on Aging, Baltimore, MD, USA
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de Jong JCBC, Attema BJ, van der Hoek MD, Verschuren L, Caspers MPM, Kleemann R, van der Leij FR, van den Hoek AM, Nieuwenhuizen AG, Keijer J. Sex differences in skeletal muscle-aging trajectory: same processes, but with a different ranking. GeroScience 2023; 45:2367-2386. [PMID: 36820956 PMCID: PMC10651666 DOI: 10.1007/s11357-023-00750-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2022] [Accepted: 02/02/2023] [Indexed: 02/24/2023] Open
Abstract
Sex differences in muscle aging are poorly understood, but could be crucial for the optimization of sarcopenia-related interventions. To gain insight into potential sex differences in muscle aging, we recruited young (23 ± 2 years, 13 males and 13 females) and old (80 ± 3.5 years, 28 males and 26 females) participants. Males and females in both groups were highly matched, and vastus lateralis muscle parameters of old versus young participants were compared for each sex separately, focusing on gene expression. The overall gene expression profiles separated the sexes, but similar gene expression patterns separated old from young participants in males and females. Genes were indeed regulated in the same direction in both sexes during aging; however, the magnitude of differential expression was sex specific. In males, oxidative phosphorylation was the top-ranked differentially expressed process, and in females, this was cell growth mediated by AKT signaling. Findings from RNA-seq data were studied in greater detail using alternative approaches. In addition, we confirmed our data using publicly available data from three independent human studies. In conclusion, top-ranked pathways differ between males and females, but were present and altered in the same direction in both sexes. We conclude that the same processes are associated with skeletal muscle aging in males and females, but the differential expression of those processes in old vs. young participants is sex specific.
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Affiliation(s)
- Jelle C B C de Jong
- Human and Animal Physiology, Wageningen University, 6700AH, Wageningen, The Netherlands
- Department of Metabolic Health Research, The Netherlands Organization for Applied Scientific Research (TNO), Leiden, The Netherlands
| | - Brecht J Attema
- Human and Animal Physiology, Wageningen University, 6700AH, Wageningen, The Netherlands
| | - Marjanne D van der Hoek
- Human and Animal Physiology, Wageningen University, 6700AH, Wageningen, The Netherlands
- Applied Research Centre Food and Dairy, Van Hall Larenstein University of Applied Sciences, Leeuwarden, The Netherlands
- MCL Academy, Medical Centre Leeuwarden, Leeuwarden, The Netherlands
| | - Lars Verschuren
- Department of Microbiology and Systems Biology, The Netherlands Organization for Applied Scientific Research (TNO), Zeist, The Netherlands
| | - Martien P M Caspers
- Department of Microbiology and Systems Biology, The Netherlands Organization for Applied Scientific Research (TNO), Zeist, The Netherlands
| | - Robert Kleemann
- Department of Metabolic Health Research, The Netherlands Organization for Applied Scientific Research (TNO), Leiden, The Netherlands
| | - Feike R van der Leij
- Applied Research Centre Food and Dairy, Van Hall Larenstein University of Applied Sciences, Leeuwarden, The Netherlands
- Research and Innovation Centre Agri, Food & Life Sciences, Inholland University of Applied Sciences, Delft and Amsterdam, The Netherlands
| | - Anita M van den Hoek
- Department of Metabolic Health Research, The Netherlands Organization for Applied Scientific Research (TNO), Leiden, The Netherlands
| | - Arie G Nieuwenhuizen
- Human and Animal Physiology, Wageningen University, 6700AH, Wageningen, The Netherlands
| | - Jaap Keijer
- Human and Animal Physiology, Wageningen University, 6700AH, Wageningen, The Netherlands.
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8
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de Jong JCBC, Verschuren L, Caspers MPM, van der Hoek MD, van der Leij FR, Kleemann R, van den Hoek AM, Nieuwenhuizen AG, Keijer J. Evidence for sex-specific intramuscular changes associated to physical weakness in adults older than 75 years. Biol Sex Differ 2023; 14:45. [PMID: 37430322 DOI: 10.1186/s13293-023-00531-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/14/2023] [Accepted: 06/29/2023] [Indexed: 07/12/2023] Open
Abstract
BACKGROUND Physical weakness is a key component of frailty, and is highly prevalent in older adults. While females have a higher prevalence and earlier onset, sex differences in the development of frailty-related physical weakness are hardly studied. Therefore, we investigated the intramuscular changes that differentiate between fit and weak older adults for each sex separately. METHODS Male (n = 28) and female (n = 26) older adults (75 + years) were grouped on the basis of their ranks according to three frailty-related physical performance criteria. Muscle biopsies taken from vastus lateralis muscle were used for transcriptome and histological examination. Pairwise comparisons were made between the fittest and weakest groups for each sex separately, and potential sex-specific effects were assessed. RESULTS Weak females were characterized by a higher expression of inflammatory pathways and infiltration of NOX2-expressing immune cells, concomitant with a higher VCAM1 expression. Weak males were characterized by a smaller diameter of type 2 (fast) myofibers and lower expression of PRKN. In addition, weakness-associated transcriptome changes in the muscle were distinct from aging, suggesting that the pathophysiology of frailty-associated physical weakness does not necessarily depend on aging. CONCLUSIONS We conclude that physical weakness-associated changes in muscle are sex-specific and recommend that sex differences are taken into account in research on frailty, as these differences may have a large impact on the development of (pharmaceutical) interventions against frailty. TRIAL REGISTRATION NUMBER The FITAAL study was registered in the Dutch Trial Register, with registration code NTR6124 on 14-11-2016 ( https://trialsearch.who.int/Trial2.aspx?TrialID=NTR6124 ). HIGHLIGHTS • In female, but not male older adults, physical weakness was associated with a higher expression of intramuscular markers for inflammation. • In male, but not female older adults, physical weakness was associated with a smaller diameter of type 2 (fast) myofibers and lower PRKN expression. • Fit older adults (of both sexes) maintained expression levels comparable to young participants of weakness related genes, differing from frail participants.
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Affiliation(s)
- Jelle C B C de Jong
- Human and Animal Physiology, Wageningen University, P.O. Box 338, 6700AH, Wageningen, The Netherlands
- Department of Metabolic Health Research, The Netherlands Organization for Applied Scientific Research (TNO), Leiden, The Netherlands
| | - Lars Verschuren
- Department of Microbiology and Systems Biology, The Netherlands Organization for Applied Scientific Research (TNO), Zeist, The Netherlands
| | - Martien P M Caspers
- Department of Microbiology and Systems Biology, The Netherlands Organization for Applied Scientific Research (TNO), Zeist, The Netherlands
| | - Marjanne D van der Hoek
- Human and Animal Physiology, Wageningen University, P.O. Box 338, 6700AH, Wageningen, The Netherlands
- Applied Research Centre Food and Dairy, Van Hall Larenstein University of Applied Sciences, Leeuwarden, The Netherlands
- MCL Academy, Medical Centre Leeuwarden, Leeuwarden, The Netherlands
| | - Feike R van der Leij
- Applied Research Centre Food and Dairy, Van Hall Larenstein University of Applied Sciences, Leeuwarden, The Netherlands
- Research and Innovation Centre Agri, Food and Life Sciences, Inholland University of Applied Sciences, Delft and Amsterdam, The Netherlands
| | - Robert Kleemann
- Department of Metabolic Health Research, The Netherlands Organization for Applied Scientific Research (TNO), Leiden, The Netherlands
| | - Anita M van den Hoek
- Department of Metabolic Health Research, The Netherlands Organization for Applied Scientific Research (TNO), Leiden, The Netherlands
| | - Arie G Nieuwenhuizen
- Human and Animal Physiology, Wageningen University, P.O. Box 338, 6700AH, Wageningen, The Netherlands
| | - Jaap Keijer
- Human and Animal Physiology, Wageningen University, P.O. Box 338, 6700AH, Wageningen, The Netherlands.
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9
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de Jong JCBC, Caspers MPM, Keijzer N, Worms N, Attema J, de Ruiter C, Lek S, Nieuwenhuizen AG, Keijer J, Menke AL, Kleemann R, Verschuren L, van den Hoek AM. Caloric Restriction Combined with Immobilization as Translational Model for Sarcopenia Expressing Key-Pathways of Human Pathology. Aging Dis 2023; 14:937-957. [PMID: 37191430 DOI: 10.14336/ad.2022.1201] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2022] [Accepted: 12/01/2022] [Indexed: 05/17/2023] Open
Abstract
The prevalence of sarcopenia is increasing while it is often challenging, expensive and time-consuming to test the effectiveness of interventions against sarcopenia. Translational mouse models that adequately mimic underlying physiological pathways could accelerate research but are scarce. Here, we investigated the translational value of three potential mouse models for sarcopenia, namely partial immobilized (to mimic sedentary lifestyle), caloric restricted (CR; to mimic malnutrition) and a combination (immobilized & CR) model. C57BL/6J mice were calorically restricted (-40%) and/or one hindleg was immobilized for two weeks to induce loss of muscle mass and function. Muscle parameters were compared to those of young control (4 months) and old reference mice (21 months). Transcriptome analysis of quadriceps muscle was performed to identify underlying pathways and were compared with those being expressed in aged human vastus lateralis muscle-biopsies using a meta-analysis of five different human studies. Caloric restriction induced overall loss of lean body mass (-15%, p<0.001), whereas immobilization decreased muscle strength (-28%, p<0.001) and muscle mass of hindleg muscles specifically (on average -25%, p<0.001). The proportion of slow myofibers increased with aging in mice (+5%, p<0.05), and this was not recapitulated by the CR and/or immobilization models. The diameter of fast myofibers decreased with aging (-7%, p<0.05), and this was mimicked by all models. Transcriptome analysis revealed that the combination of CR and immobilization recapitulated more pathways characteristic for human muscle-aging (73%) than naturally aged (21 months old) mice (45%). In conclusion, the combination model exhibits loss of both muscle mass (due to CR) and function (due to immobilization) and has a remarkable similarity with pathways underlying human sarcopenia. These findings underline that external factors such as sedentary behavior and malnutrition are key elements of a translational mouse model and favor the combination model as a rapid model for testing the treatments against sarcopenia.
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Affiliation(s)
- Jelle C B C de Jong
- Department of Metabolic Health Research, The Netherlands Organization for Applied Scientific Research (TNO), Leiden, The Netherlands
- Human and Animal Physiology, Wageningen University, Wageningen, the Netherlands
| | - Martien P M Caspers
- Department of Microbiology and Systems Biology, The Netherlands Organization for Applied Scientific Research (TNO), Zeist, The Netherlands
| | - Nanda Keijzer
- Department of Metabolic Health Research, The Netherlands Organization for Applied Scientific Research (TNO), Leiden, The Netherlands
| | - Nicole Worms
- Department of Metabolic Health Research, The Netherlands Organization for Applied Scientific Research (TNO), Leiden, The Netherlands
| | - Joline Attema
- Department of Metabolic Health Research, The Netherlands Organization for Applied Scientific Research (TNO), Leiden, The Netherlands
| | - Christa de Ruiter
- Department of Metabolic Health Research, The Netherlands Organization for Applied Scientific Research (TNO), Leiden, The Netherlands
| | - Serene Lek
- Clinnovate Health UK Ltd, Glasgow, United Kingdom
| | | | - Jaap Keijer
- Human and Animal Physiology, Wageningen University, Wageningen, the Netherlands
| | - Aswin L Menke
- Department of Metabolic Health Research, The Netherlands Organization for Applied Scientific Research (TNO), Leiden, The Netherlands
| | - Robert Kleemann
- Department of Metabolic Health Research, The Netherlands Organization for Applied Scientific Research (TNO), Leiden, The Netherlands
| | - Lars Verschuren
- Department of Microbiology and Systems Biology, The Netherlands Organization for Applied Scientific Research (TNO), Zeist, The Netherlands
| | - Anita M van den Hoek
- Department of Metabolic Health Research, The Netherlands Organization for Applied Scientific Research (TNO), Leiden, The Netherlands
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10
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Barros D, Marques EA, Magalhães J, Carvalho J. Energy metabolism and frailty: The potential role of exercise-induced myokines - A narrative review. Ageing Res Rev 2022; 82:101780. [PMID: 36334911 DOI: 10.1016/j.arr.2022.101780] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Revised: 10/20/2022] [Accepted: 11/01/2022] [Indexed: 11/06/2022]
Abstract
Frailty is a complex condition that emerges from dysregulation in multiple physiological systems. Increasing evidence suggests the potential role of age-related energy dysregulation as a key driver of frailty. Exercise is considered the most efficacious intervention to prevent and even ameliorate frailty as it up-tunes and improves the function of several related systems. However, the mechanisms and molecules responsible for these intersystem benefits are not fully understood. The skeletal muscle is considered a secretory organ with endocrine functions that can produce and secrete exercise-related molecules such as myokines. These molecules are cytokines and other peptides released by muscle fibers in response to acute and/or chronic exercise. The available evidence supports that several myokines can elicit autocrine, paracrine, or endocrine effects, partly mediating inter-organ crosstalk and also having a critical role in improving cardiovascular, metabolic, immune, and neurological health. This review describes the current evidence about the potential link between energy metabolism dysregulation and frailty and provides a theoretical framework for the potential role of myokines (via exercise) in counteracting frailty. It also summarizes the physiological role of selected myokines and their response to different acute and chronic exercise protocols in older adults.
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Affiliation(s)
- Duarte Barros
- The Research Centre in Physical Activity, Health and Leisure, CIAFEL, University of Porto, Portugal; ITR - Laboratory for Integrative and Translational Research in Population Health, Porto, Portugal.
| | - Elisa A Marques
- Research Center in Sports Sciences, Health Sciences and Human Development, CIDESD, University of Maia (ISMAI), Portugal; School of Sport and Exercise Sciences, Loughborough University, Loughborough, UK
| | - José Magalhães
- The Research Centre in Physical Activity, Health and Leisure, CIAFEL, University of Porto, Portugal; ITR - Laboratory for Integrative and Translational Research in Population Health, Porto, Portugal
| | - Joana Carvalho
- The Research Centre in Physical Activity, Health and Leisure, CIAFEL, University of Porto, Portugal; ITR - Laboratory for Integrative and Translational Research in Population Health, Porto, Portugal
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11
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Pacheco NL, Noren Hooten N, Zhang Y, Prince CS, Mode NA, Ezike N, Becker KG, Zonderman AB, Evans MK. Sex-specific transcriptome differences in a middle-aged frailty cohort. BMC Geriatr 2022; 22:651. [PMID: 35945487 PMCID: PMC9361278 DOI: 10.1186/s12877-022-03326-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2022] [Accepted: 07/20/2022] [Indexed: 11/25/2022] Open
Abstract
Background Frailty is a clinical syndrome described as reduced physiological reserve and increased vulnerability. Typically examined in older adults, recent work shows frailty occurs in middle-aged individuals and is associated with increased mortality. Previous investigation of global transcriptome changes in a middle-aged cohort from the Healthy Aging in Neighborhoods of Diversity across the Life Span (HANDLS) study demonstrated inflammatory genes and pathways were significantly altered by frailty status and race. Transcriptome differences in frailty by sex remain unclear. We sought to discover novel genes and pathways associated with sex and frailty in a diverse middle-aged cohort using RNA-Sequencing. Methods Differential gene expression and pathway analyses were performed in peripheral blood mononuclear cells for 1) frail females (FRAF, n = 4) vs non-frail females (NORF, n = 4), 2) frail males (FRAM, n = 4) vs non-frail males (NORM, n = 4), 3) FRAM vs FRAF, and 4) NORM vs NORF. We evaluated exclusive significant genes and pathways, as well as overlaps, between the comparison groups. Results Over 80% of the significant genes exclusive to FRAF vs NORF, FRAM vs NORM, and FRAM vs FRAF, respectively, were novel and associated with various biological functions. Pathways exclusive to FRAF vs NORF were associated with reduced inflammation, while FRAM vs NORM exclusive pathways were related to aberrant musculoskeletal physiology. Pathways exclusive to FRAM vs FRAF were associated with reduced cell cycle regulation and activated catabolism and Coronavirus pathogenesis. Conclusions Our results indicate sex-specific transcriptional changes occur in middle-aged frailty, enhancing knowledge on frailty progression and potential therapeutic targets to prevent frailty. Supplementary Information The online version contains supplementary material available at 10.1186/s12877-022-03326-7.
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Affiliation(s)
- Natasha L Pacheco
- Laboratory of Epidemiology and Population Sciences, National Institute On Aging, National Institutes of Health, Baltimore, MD, USA
| | - Nicole Noren Hooten
- Laboratory of Epidemiology and Population Sciences, National Institute On Aging, National Institutes of Health, Baltimore, MD, USA
| | - Yongqing Zhang
- Laboratory of Genetics and Genomics, National Institute On Aging, National Institutes of Health, Baltimore, MD, USA
| | - Calais S Prince
- Laboratory of Epidemiology and Population Sciences, National Institute On Aging, National Institutes of Health, Baltimore, MD, USA
| | - Nicolle A Mode
- Laboratory of Epidemiology and Population Sciences, National Institute On Aging, National Institutes of Health, Baltimore, MD, USA
| | - Ngozi Ezike
- Laboratory of Epidemiology and Population Sciences, National Institute On Aging, National Institutes of Health, Baltimore, MD, USA
| | - Kevin G Becker
- Laboratory of Genetics and Genomics, National Institute On Aging, National Institutes of Health, Baltimore, MD, USA
| | - Alan B Zonderman
- Laboratory of Epidemiology and Population Sciences, National Institute On Aging, National Institutes of Health, Baltimore, MD, USA
| | - Michele K Evans
- Laboratory of Epidemiology and Population Sciences, National Institute On Aging, National Institutes of Health, Baltimore, MD, USA.
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12
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Lagerwaard B, Nieuwenhuizen AG, Bunschoten A, de Boer VC, Keijer J. Matrisome, innervation and oxidative metabolism affected in older compared with younger males with similar physical activity. J Cachexia Sarcopenia Muscle 2021; 12:1214-1231. [PMID: 34219410 PMCID: PMC8517362 DOI: 10.1002/jcsm.12753] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/12/2020] [Revised: 04/29/2021] [Accepted: 06/08/2021] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND Due to the interaction between skeletal muscle ageing and lifestyle factors, it is often challenging to attribute the decline in muscle mass and quality to either changes in lifestyle or to advancing age itself. Because many of the physiological factors affecting muscle mass and quality are modulated by physical activity and physical activity declines with age, the aim of this study is to better understand the effects of early ageing on muscle function by comparing a population of healthy older and young males with similar physical activity patterns. METHODS Eighteen older (69 ± 2.0 years) and 20 young (22 ± 2.0 years) males were recruited based on similar self-reported physical activity, which was verified using accelerometry measurements. Gene expression profiles of vastus lateralis biopsies obtained by RNA sequencing were compared, and key results were validated using quantitative polymerase chain reaction and western blot. RESULTS Total physical activity energy expenditure was similar between the young and old group (404 ± 215 vs. 411 ± 189 kcal/day, P = 0.11). Three thousand seven hundred ninety-seven differentially expressed coding genes (DEGs) were identified (adjusted P-value cut-off of <0.05), of which 1891 were higher and 1906 were lower expressed in the older muscle. The matrisome, innervation and inflammation were the main upregulated processes, and oxidative metabolism was the main downregulated process in old compared with young muscle. Lower protein levels of mitochondrial transcription factor A (TFAM, P = 0.030) and mitochondrial respiratory Complexes IV and II (P = 0.011 and P = 0.0009, respectively) were observed, whereas a trend was observed for Complex I (P = 0.062), in older compared with young muscle. Protein expression of Complexes I and IV was significantly correlated to mitochondrial capacity in the vastus lateralis as measured in vivo (P = 0.017, R2 = 0.42 and P = 0.030, R2 = 0.36). A trend for higher muscle-specific receptor kinase (MUSK) protein levels in the older group was observed (P = 0.08). CONCLUSIONS There are clear differences in the transcriptome signatures of the vastus lateralis muscle of healthy older and young males with similar physical activity levels, including significant differences at the protein level. By disentangling physical activity and ageing, we appoint early skeletal muscle ageing processes that occur despite similar physical activity. Improved understanding of these processes will be key to design targeted anti-ageing therapies.
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Affiliation(s)
- Bart Lagerwaard
- Human and Animal PhysiologyWageningen University and ResearchWageningenThe Netherlands
- TI Food and NutritionWageningenThe Netherlands
| | - Arie G. Nieuwenhuizen
- Human and Animal PhysiologyWageningen University and ResearchWageningenThe Netherlands
| | - Annelies Bunschoten
- Human and Animal PhysiologyWageningen University and ResearchWageningenThe Netherlands
| | - Vincent C.J. de Boer
- Human and Animal PhysiologyWageningen University and ResearchWageningenThe Netherlands
| | - Jaap Keijer
- Human and Animal PhysiologyWageningen University and ResearchWageningenThe Netherlands
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13
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Lagerwaard B, van der Hoek MD, Hoeks J, Grevendonk L, Nieuwenhuizen AG, Keijer J, de Boer VCJ. Propionate hampers differentiation and modifies histone propionylation and acetylation in skeletal muscle cells. Mech Ageing Dev 2021; 196:111495. [PMID: 33932454 DOI: 10.1016/j.mad.2021.111495] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2020] [Revised: 04/20/2021] [Accepted: 04/21/2021] [Indexed: 12/19/2022]
Abstract
Protein acylation via metabolic acyl-CoA intermediates provides a link between cellular metabolism and protein functionality. A process in which acetyl-CoA and acetylation are fine-tuned is during myogenic differentiation. However, the roles of other protein acylations remain unknown. Protein propionylation could be functionally relevant because propionyl-CoA can be derived from the catabolism of amino acids and fatty acids and was shown to decrease during muscle differentiation. We aimed to explore the potential role of protein propionylation in muscle differentiation, by mimicking a pathophysiological situation with high extracellular propionate which increases propionyl-CoA and protein propionylation, rendering it a model to study increased protein propionylation. Exposure to extracellular propionate, but not acetate, impaired myogenic differentiation in C2C12 cells and propionate exposure impaired myogenic differentiation in primary human muscle cells. Impaired differentiation was accompanied by an increase in histone propionylation as well as histone acetylation. Furthermore, chromatin immunoprecipitation showed increased histone propionylation at specific regulatory myogenic differentiation sites of the Myod gene. Intramuscular propionylcarnitine levels are higher in old compared to young males and females, possibly indicating increased propionyl-CoA levels with age. The findings suggest a role for propionylation and propionyl-CoA in regulation of muscle cell differentiation and ageing, possibly via alterations in histone acylation.
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Affiliation(s)
- Bart Lagerwaard
- Human and Animal Physiology, Wageningen University and Research, PO Box 338, 6700 AH, Wageningen, the Netherlands; TI Food and Nutrition, P.O. Box 557, 6700 AN, Wageningen, the Netherlands
| | - Marjanne D van der Hoek
- Human and Animal Physiology, Wageningen University and Research, PO Box 338, 6700 AH, Wageningen, the Netherlands; Applied Research Centre Food and Dairy, Van Hall Larenstein University of Applied Sciences, Leeuwarden, the Netherlands; MCL Academy, Medical Centre Leeuwarden, Leeuwarden, the Netherlands
| | - Joris Hoeks
- Department of Nutrition and Movement Sciences, NUTRIM School for Nutrition and Translational Research in Metabolism, Maastricht University, 6200 MD, Maastricht, the Netherlands
| | - Lotte Grevendonk
- TI Food and Nutrition, P.O. Box 557, 6700 AN, Wageningen, the Netherlands; Department of Nutrition and Movement Sciences, NUTRIM School for Nutrition and Translational Research in Metabolism, Maastricht University, 6200 MD, Maastricht, the Netherlands
| | - Arie G Nieuwenhuizen
- Human and Animal Physiology, Wageningen University and Research, PO Box 338, 6700 AH, Wageningen, the Netherlands
| | - Jaap Keijer
- Human and Animal Physiology, Wageningen University and Research, PO Box 338, 6700 AH, Wageningen, the Netherlands
| | - Vincent C J de Boer
- Human and Animal Physiology, Wageningen University and Research, PO Box 338, 6700 AH, Wageningen, the Netherlands.
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14
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Baraniuk JN, Kern G, Narayan V, Cheema A. Exercise modifies glutamate and other metabolic biomarkers in cerebrospinal fluid from Gulf War Illness and Myalgic encephalomyelitis / Chronic Fatigue Syndrome. PLoS One 2021; 16:e0244116. [PMID: 33440400 PMCID: PMC7806361 DOI: 10.1371/journal.pone.0244116] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2020] [Accepted: 12/02/2020] [Indexed: 12/21/2022] Open
Abstract
Myalgic encephalomyelitis / Chronic Fatigue Syndrome (ME/CFS) and Gulf War Illness (GWI) share many symptoms of fatigue, pain, and cognitive dysfunction that are not relieved by rest. Patterns of serum metabolites in ME/CFS and GWI are different from control groups and suggest potential dysfunction of energy and lipid metabolism. The metabolomics of cerebrospinal fluid was contrasted between ME/CFS, GWI and sedentary controls in 2 sets of subjects who had lumbar punctures after either (a) rest or (b) submaximal exercise stress tests. Postexercise GWI and control subjects were subdivided according to acquired transient postexertional postural tachycardia. Banked cerebrospinal fluid specimens were assayed using Biocrates AbsoluteIDQ® p180 kits for quantitative targeted metabolomics studies of amino acids, amines, acylcarnitines, sphingolipids, lysophospholipids, alkyl and ether phosphocholines. Glutamate was significantly higher in the subgroup of postexercise GWI subjects who did not develop postural tachycardia after exercise compared to nonexercise and other postexercise groups. The only difference between nonexercise groups was higher lysoPC a C28:0 in GWI than ME/CFS suggesting this biochemical or phospholipase activities may have potential as a biomarker to distinguish between the 2 diseases. Exercise effects were suggested by elevation of short chain acylcarnitine C5-OH (C3-DC-M) in postexercise controls compared to nonexercise ME/CFS. Limitations include small subgroup sample sizes and absence of postexercise ME/CFS specimens. Mechanisms of glutamate neuroexcitotoxicity may contribute to neuropathology and “neuroinflammation” in the GWI subset who did not develop postural tachycardia after exercise. Dysfunctional lipid metabolism may distinguish the predominantly female ME/CFS group from predominantly male GWI subjects.
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Affiliation(s)
- James N Baraniuk
- Department of Medicine, Georgetown University, Washington, DC, United States of America
| | - Grant Kern
- Department of Medicine, Georgetown University, Washington, DC, United States of America
| | - Vaishnavi Narayan
- Department of Medicine, Georgetown University, Washington, DC, United States of America
| | - Amrita Cheema
- Department of Oncology, Georgetown Lombardi Comprehensive Cancer Centre, Georgetown University, Washington, DC, United States of America
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