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Cheng YW, Anzell AR, Morosky SA, Schwartze TA, Hinck CS, Hinck AP, Roman BL, Davidson LA. Shear Stress and Sub-Femtomolar Levels of Ligand Synergize to Activate ALK1 Signaling in Endothelial Cells. Cells 2024; 13:285. [PMID: 38334677 PMCID: PMC10854672 DOI: 10.3390/cells13030285] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2023] [Revised: 01/17/2024] [Accepted: 01/26/2024] [Indexed: 02/10/2024] Open
Abstract
Endothelial cells (ECs) respond to concurrent stimulation by biochemical factors and wall shear stress (SS) exerted by blood flow. Disruptions in flow-induced responses can result in remodeling issues and cardiovascular diseases, but the detailed mechanisms linking flow-mechanical cues and biochemical signaling remain unclear. Activin receptor-like kinase 1 (ALK1) integrates SS and ALK1-ligand cues in ECs; ALK1 mutations cause hereditary hemorrhagic telangiectasia (HHT), marked by arteriovenous malformation (AVM) development. However, the mechanistic underpinnings of ALK1 signaling modulation by fluid flow and the link to AVMs remain uncertain. We recorded EC responses under varying SS magnitudes and ALK1 ligand concentrations by assaying pSMAD1/5/9 nuclear localization using a custom multi-SS microfluidic device and a custom image analysis pipeline. We extended the previously reported synergy between SS and BMP9 to include BMP10 and BMP9/10. Moreover, we demonstrated that this synergy is effective even at extremely low SS magnitudes (0.4 dyn/cm2) and ALK1 ligand range (femtogram/mL). The synergistic response to ALK1 ligands and SS requires the kinase activity of ALK1. Moreover, ALK1's basal activity and response to minimal ligand levels depend on endocytosis, distinct from cell-cell junctions, cytoskeleton-mediated mechanosensing, or cholesterol-enriched microdomains. However, an in-depth analysis of ALK1 receptor trafficking's molecular mechanisms requires further investigation.
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Affiliation(s)
- Ya-Wen Cheng
- Department of Bioengineering, Swanson School of Engineering, University of Pittsburgh, Pittsburgh, PA 15261, USA;
| | - Anthony R. Anzell
- Department of Human Genetics, School of Public Health, University of Pittsburgh, Pittsburgh, PA 15261, USA
| | - Stefanie A. Morosky
- Department of Human Genetics, School of Public Health, University of Pittsburgh, Pittsburgh, PA 15261, USA
| | - Tristin A. Schwartze
- Department of Structural Biology, School of Medicine, University of Pittsburgh, Pittsburgh, PA 15261, USA
| | - Cynthia S. Hinck
- Department of Structural Biology, School of Medicine, University of Pittsburgh, Pittsburgh, PA 15261, USA
| | - Andrew P. Hinck
- Department of Structural Biology, School of Medicine, University of Pittsburgh, Pittsburgh, PA 15261, USA
| | - Beth L. Roman
- Department of Human Genetics, School of Public Health, University of Pittsburgh, Pittsburgh, PA 15261, USA
- Heart, Lung, Blood and Vascular Medicine Institute, University of Pittsburgh, Pittsburgh, PA 15261, USA
| | - Lance A. Davidson
- Department of Bioengineering, Swanson School of Engineering, University of Pittsburgh, Pittsburgh, PA 15261, USA;
- Department of Developmental Biology, School of Medicine, University of Pittsburgh, Pittsburgh, PA 15261, USA
- Department of Computational and Systems Biology, School of Medicine, University of Pittsburgh, Pittsburgh, PA 15261, USA
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Anzell AR, Kunz AB, Donovan JP, Tran TG, Lu X, Young S, Roman BL. Blood flow regulates acvrl1 transcription via ligand-dependent Alk1 activity. bioRxiv 2024:2024.01.25.576046. [PMID: 38328175 PMCID: PMC10849739 DOI: 10.1101/2024.01.25.576046] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/09/2024]
Abstract
Hereditary hemorrhagic telangiectasia (HHT) is an autosomal dominant disease characterized by the development of arteriovenous malformations (AVMs) that can result in significant morbidity and mortality. HHT is caused primarily by mutations in bone morphogenetic protein receptors ACVRL1/ALK1, a signaling receptor, or endoglin (ENG), an accessory receptor. Because overexpression of Acvrl1 prevents AVM development in both Acvrl1 and Eng null mice, enhancing ACVRL1 expression may be a promising approach to development of targeted therapies for HHT. Therefore, we sought to understand the molecular mechanism of ACVRL1 regulation. We previously demonstrated in zebrafish embryos that acvrl1 is predominantly expressed in arterial endothelial cells and that expression requires blood flow. Here, we document that flow dependence exhibits regional heterogeneity and that acvrl1 expression is rapidly restored after reinitiation of flow. Furthermore, we find that acvrl1 expression is significantly decreased in mutants that lack the circulating Alk1 ligand, Bmp10, and that BMP10 microinjection into the vasculature in the absence of flow enhances acvrl1 expression in an Alk1-dependent manner. Using a transgenic acvrl1:egfp reporter line, we find that flow and Bmp10 regulate acvrl1 at the level of transcription. Finally, we observe similar ALK1 ligand-dependent increases in ACVRL1 in human endothelial cells subjected to shear stress. These data suggest that Bmp10 acts downstream of blood flow to maintain or enhance acvrl1 expression via a positive feedback mechanism, and that ALK1 activating therapeutics may have dual functionality by increasing both ALK1 signaling flux and ACVRL1 expression.
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Affiliation(s)
- Anthony R. Anzell
- Department of Human Genetics, University of Pittsburgh School of Public Health, Pittsburgh, PA, USA
- Pittsburgh Heart, Lung and Blood Vascular Medicine Institute, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Amy Biery Kunz
- Department of Human Genetics, University of Pittsburgh School of Public Health, Pittsburgh, PA, USA
- Current affiliation: Allegheny Health Network, Pittsburgh, PA, USA
| | - James P. Donovan
- Department of Human Genetics, University of Pittsburgh School of Public Health, Pittsburgh, PA, USA
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA, USA
| | - Thanhlong G. Tran
- Department of Human Genetics, University of Pittsburgh School of Public Health, Pittsburgh, PA, USA
- Current affiliation: National Cancer Institute, National Institutes of Health, Bethesda, MD, USA
| | - Xinyan Lu
- Department of Human Genetics, University of Pittsburgh School of Public Health, Pittsburgh, PA, USA
| | - Sarah Young
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA, USA
- Current affiliation: Carnegie Mellon University, University Libraries, Pittsburgh, PA, USA
| | - Beth L. Roman
- Department of Human Genetics, University of Pittsburgh School of Public Health, Pittsburgh, PA, USA
- Pittsburgh Heart, Lung and Blood Vascular Medicine Institute, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
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Wider JM, Gruley E, Morse PT, Wan J, Lee I, Anzell AR, Fogo GM, Mathieu J, Hish G, O'Neil B, Neumar RW, Przyklenk K, Hüttemann M, Sanderson TH. Modulation of mitochondrial function with near-infrared light reduces brain injury in a translational model of cardiac arrest. Crit Care 2023; 27:491. [PMID: 38098060 PMCID: PMC10720207 DOI: 10.1186/s13054-023-04745-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2023] [Accepted: 11/18/2023] [Indexed: 12/18/2023] Open
Abstract
BACKGROUND Brain injury is a leading cause of morbidity and mortality in patients resuscitated from cardiac arrest. Mitochondrial dysfunction contributes to brain injury following cardiac arrest; therefore, therapies that limit mitochondrial dysfunction have the potential to improve neurological outcomes. Generation of reactive oxygen species (ROS) during ischemia-reperfusion injury in the brain is a critical component of mitochondrial injury and is dependent on hyperactivation of mitochondria following resuscitation. Our previous studies have provided evidence that modulating mitochondrial function with specific near-infrared light (NIR) wavelengths can reduce post-ischemic mitochondrial hyperactivity, thereby reducing brain injury during reperfusion in multiple small animal models. METHODS Isolated porcine brain cytochrome c oxidase (COX) was used to investigate the mechanism of NIR-induced mitochondrial modulation. Cultured primary neurons from mice expressing mitoQC were utilized to explore the mitochondrial mechanisms related to protection with NIR following ischemia-reperfusion. Anesthetized pigs were used to optimize the delivery of NIR to the brain by measuring the penetration depth of NIR to deep brain structures and tissue heating. Finally, a model of out-of-hospital cardiac arrest with CPR in adult pigs was used to evaluate the translational potential of NIR as a noninvasive therapeutic approach to protect the brain after resuscitation. RESULTS Molecular evaluation of enzyme activity during NIR irradiation demonstrated COX function was reduced in an intensity-dependent manner with a threshold of enzyme inhibition leading to a moderate reduction in activity without complete inhibition. Mechanistic interrogation in neurons demonstrated that mitochondrial swelling and upregulation of mitophagy were reduced with NIR treatment. NIR therapy in large animals is feasible, as NIR penetrates deep into the brain without substantial tissue heating. In a translational porcine model of CA/CPR, transcranial NIR treatment for two hours at the onset of return of spontaneous circulation (ROSC) demonstrated significantly improved neurological deficit scores and reduced histologic evidence of brain injury after resuscitation from cardiac arrest. CONCLUSIONS NIR modulates mitochondrial function which improves mitochondrial dynamics and quality control following ischemia/reperfusion. Noninvasive modulation of mitochondria, achieved by transcranial treatment of the brain with NIR, mitigates post-cardiac arrest brain injury and improves neurologic functional outcomes.
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Affiliation(s)
- Joseph M Wider
- Department of Emergency Medicine, University of Michigan, 1500 East Medical Center Drive, Ann Arbor, MI, 48109-5014, USA
- Max Harry Weil Institute for Critical Care Research and Innovation, University of Michigan, B10-103A, NCRC 2800 Plymouth Road, Ann Arbor, MI, 48109, USA
- Department of Molecular and Integrative Physiology, University of Michigan, 7744 MS II, 1137 E. Catherine St., Ann Arbor, MI, 48109-5622, USA
| | - Erin Gruley
- Department of Emergency Medicine, University of Michigan, 1500 East Medical Center Drive, Ann Arbor, MI, 48109-5014, USA
- Max Harry Weil Institute for Critical Care Research and Innovation, University of Michigan, B10-103A, NCRC 2800 Plymouth Road, Ann Arbor, MI, 48109, USA
| | - Paul T Morse
- Center for Molecular Medicine and Genetics, Wayne State University, 3214 Scott Hall, 540 E. Canfield Ave., Detroit, MI, 48201, USA
| | - Junmei Wan
- Center for Molecular Medicine and Genetics, Wayne State University, 3214 Scott Hall, 540 E. Canfield Ave., Detroit, MI, 48201, USA
| | - Icksoo Lee
- College of Medicine, Dankook University, Cheonan-Si, Chungcheongnam-Do, 31116, Republic of Korea
| | - Anthony R Anzell
- Department of Human Genetics, University of Pittsburgh, 130 De Soto Street, Pittsburgh, PA, 15261, USA
| | - Garrett M Fogo
- Department of Emergency Medicine, University of Michigan, 1500 East Medical Center Drive, Ann Arbor, MI, 48109-5014, USA
- Neuroscience Graduate Program, University of Michigan, 204 Washtenaw Ave, Ann Arbor, MI, 48109, USA
| | - Jennifer Mathieu
- Department of Emergency Medicine, University of Michigan, 1500 East Medical Center Drive, Ann Arbor, MI, 48109-5014, USA
- Max Harry Weil Institute for Critical Care Research and Innovation, University of Michigan, B10-103A, NCRC 2800 Plymouth Road, Ann Arbor, MI, 48109, USA
- Department of Molecular and Integrative Physiology, University of Michigan, 7744 MS II, 1137 E. Catherine St., Ann Arbor, MI, 48109-5622, USA
| | - Gerald Hish
- Unit for Laboratory Animal Medicine, University of Michigan, North Campus Research Complex, 2800 Plymouth Rd, Ann Arbor, MI, 48109, USA
| | - Brian O'Neil
- Department of Emergency Medicine, Wayne State University, 4201 St. Antoine St., University Health Center - 6G, Detroit, MI, 48201, USA
| | - Robert W Neumar
- Department of Emergency Medicine, University of Michigan, 1500 East Medical Center Drive, Ann Arbor, MI, 48109-5014, USA
- Max Harry Weil Institute for Critical Care Research and Innovation, University of Michigan, B10-103A, NCRC 2800 Plymouth Road, Ann Arbor, MI, 48109, USA
| | - Karin Przyklenk
- Clinical Research Institute, Children's Hospital of Michigan, 3901 Beaubien Blvd, Detroit, MI, USA
- Department of Pediatrics, Central Michigan University, 1280 S. East Campus Drive, Mount Pleasant, MI, 48859, USA
| | - Maik Hüttemann
- Center for Molecular Medicine and Genetics, Wayne State University, 3214 Scott Hall, 540 E. Canfield Ave., Detroit, MI, 48201, USA
| | - Thomas H Sanderson
- Department of Emergency Medicine, University of Michigan, 1500 East Medical Center Drive, Ann Arbor, MI, 48109-5014, USA.
- Max Harry Weil Institute for Critical Care Research and Innovation, University of Michigan, B10-103A, NCRC 2800 Plymouth Road, Ann Arbor, MI, 48109, USA.
- Department of Molecular and Integrative Physiology, University of Michigan, 7744 MS II, 1137 E. Catherine St., Ann Arbor, MI, 48109-5622, USA.
- Neuroscience Graduate Program, University of Michigan, 204 Washtenaw Ave, Ann Arbor, MI, 48109, USA.
- Department of Emergency Medicine, Wayne State University, 4201 St. Antoine St., University Health Center - 6G, Detroit, MI, 48201, USA.
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Anzell AR, Fogo GM, Gurm Z, Raghunayakula S, Wider JM, Maheras KJ, Emaus KJ, Bryson TD, Wang M, Neumar RW, Przyklenk K, Sanderson TH. Mitochondrial fission and mitophagy are independent mechanisms regulating ischemia/reperfusion injury in primary neurons. Cell Death Dis 2021; 12:475. [PMID: 33980811 PMCID: PMC8115279 DOI: 10.1038/s41419-021-03752-2] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Revised: 04/21/2021] [Accepted: 04/22/2021] [Indexed: 02/03/2023]
Abstract
Mitochondrial dynamics and mitophagy are constitutive and complex systems that ensure a healthy mitochondrial network through the segregation and subsequent degradation of damaged mitochondria. Disruption of these systems can lead to mitochondrial dysfunction and has been established as a central mechanism of ischemia/reperfusion (I/R) injury. Emerging evidence suggests that mitochondrial dynamics and mitophagy are integrated systems; however, the role of this relationship in the context of I/R injury remains unclear. To investigate this concept, we utilized primary cortical neurons isolated from the novel dual-reporter mitochondrial quality control knockin mice (C57BL/6-Gt(ROSA)26Sortm1(CAG-mCherry/GFP)Ganl/J) with conditional knockout (KO) of Drp1 to investigate changes in mitochondrial dynamics and mitophagic flux during in vitro I/R injury. Mitochondrial dynamics was quantitatively measured in an unbiased manner using a machine learning mitochondrial morphology classification system, which consisted of four different classifications: network, unbranched, swollen, and punctate. Evaluation of mitochondrial morphology and mitophagic flux in primary neurons exposed to oxygen-glucose deprivation (OGD) and reoxygenation (OGD/R) revealed extensive mitochondrial fragmentation and swelling, together with a significant upregulation in mitophagic flux. Furthermore, the primary morphology of mitochondria undergoing mitophagy was classified as punctate. Colocalization using immunofluorescence as well as western blot analysis revealed that the PINK1/Parkin pathway of mitophagy was activated following OGD/R. Conditional KO of Drp1 prevented mitochondrial fragmentation and swelling following OGD/R but did not alter mitophagic flux. These data provide novel evidence that Drp1 plays a causal role in the progression of I/R injury, but mitophagy does not require Drp1-mediated mitochondrial fission.
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Affiliation(s)
- Anthony R. Anzell
- grid.214458.e0000000086837370Department of Emergency Medicine, University of Michigan Medical School, Ann Arbor, MI 48109 USA ,grid.254444.70000 0001 1456 7807Department of Physiology, Wayne State University School of Medicine, Detroit, MI 48201 USA ,grid.21925.3d0000 0004 1936 9000Department of Human Genetics, University of Pittsburgh, Pittsburgh, PA 15269 USA
| | - Garrett M. Fogo
- grid.214458.e0000000086837370Department of Emergency Medicine, University of Michigan Medical School, Ann Arbor, MI 48109 USA ,grid.214458.e0000000086837370Neuroscience Graduate Program, University of Michigan Medical School, Ann Arbor, MI 48109 USA
| | - Zoya Gurm
- grid.214458.e0000000086837370Department of Emergency Medicine, University of Michigan Medical School, Ann Arbor, MI 48109 USA ,grid.214458.e0000000086837370Frankel Cardiovascular Center, University of Michigan Medical School, Ann Arbor, MI 48109 USA
| | - Sarita Raghunayakula
- grid.214458.e0000000086837370Department of Emergency Medicine, University of Michigan Medical School, Ann Arbor, MI 48109 USA
| | - Joseph M. Wider
- grid.214458.e0000000086837370Department of Emergency Medicine, University of Michigan Medical School, Ann Arbor, MI 48109 USA
| | - Kathleen J. Maheras
- grid.214458.e0000000086837370Department of Emergency Medicine, University of Michigan Medical School, Ann Arbor, MI 48109 USA
| | - Katlynn J. Emaus
- grid.214458.e0000000086837370Department of Emergency Medicine, University of Michigan Medical School, Ann Arbor, MI 48109 USA ,grid.214458.e0000000086837370Neuroscience Graduate Program, University of Michigan Medical School, Ann Arbor, MI 48109 USA
| | - Timothy D. Bryson
- grid.214458.e0000000086837370Department of Emergency Medicine, University of Michigan Medical School, Ann Arbor, MI 48109 USA ,grid.214458.e0000000086837370Frankel Cardiovascular Center, University of Michigan Medical School, Ann Arbor, MI 48109 USA
| | - Madison Wang
- grid.254444.70000 0001 1456 7807Department of Physiology, Wayne State University School of Medicine, Detroit, MI 48201 USA
| | - Robert W. Neumar
- grid.214458.e0000000086837370Department of Emergency Medicine, University of Michigan Medical School, Ann Arbor, MI 48109 USA
| | - Karin Przyklenk
- grid.254444.70000 0001 1456 7807Department of Physiology, Wayne State University School of Medicine, Detroit, MI 48201 USA
| | - Thomas H. Sanderson
- grid.214458.e0000000086837370Department of Emergency Medicine, University of Michigan Medical School, Ann Arbor, MI 48109 USA ,grid.214458.e0000000086837370Neuroscience Graduate Program, University of Michigan Medical School, Ann Arbor, MI 48109 USA ,grid.214458.e0000000086837370Frankel Cardiovascular Center, University of Michigan Medical School, Ann Arbor, MI 48109 USA ,grid.214458.e0000000086837370Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI 48109 USA
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Anzell AR, Maizy R, Przyklenk K, Sanderson TH. Mitochondrial Quality Control and Disease: Insights into Ischemia-Reperfusion Injury. Mol Neurobiol 2018; 55:2547-2564. [PMID: 28401475 PMCID: PMC5636654 DOI: 10.1007/s12035-017-0503-9] [Citation(s) in RCA: 241] [Impact Index Per Article: 40.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2017] [Accepted: 03/20/2017] [Indexed: 12/28/2022]
Abstract
Mitochondria are key regulators of cell fate during disease. They control cell survival via the production of ATP that fuels cellular processes and, conversely, cell death via the induction of apoptosis through release of pro-apoptotic factors such as cytochrome C. Therefore, it is essential to have stringent quality control mechanisms to ensure a healthy mitochondrial network. Quality control mechanisms are largely regulated by mitochondrial dynamics and mitophagy. The processes of mitochondrial fission (division) and fusion allow for damaged mitochondria to be segregated and facilitate the equilibration of mitochondrial components such as DNA, proteins, and metabolites. The process of mitophagy are responsible for the degradation and recycling of damaged mitochondria. These mitochondrial quality control mechanisms have been well studied in chronic and acute pathologies such as Parkinson's disease, Alzheimer's disease, stroke, and acute myocardial infarction, but less is known about how these two processes interact and contribute to specific pathophysiologic states. To date, evidence for the role of mitochondrial quality control in acute and chronic disease is divergent and suggests that mitochondrial quality control processes can serve both survival and death functions depending on the disease state. This review aims to provide a synopsis of the molecular mechanisms involved in mitochondrial quality control, to summarize our current understanding of the complex role that mitochondrial quality control plays in the progression of acute vs chronic diseases and, finally, to speculate on the possibility that targeted manipulation of mitochondrial quality control mechanisms may be exploited for the rationale design of novel therapeutic interventions.
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Affiliation(s)
- Anthony R Anzell
- Department of Emergency Medicine, Wayne State University School of Medicine, Detroit, MI, 48201, USA
- Cardiovascular Research Institute, Wayne State University School of Medicine, Detroit, MI, 48201, USA
- Department of Physiology, Wayne State University School of Medicine, Detroit, MI, 48201, USA
| | - Rita Maizy
- Department of Emergency Medicine, Wayne State University School of Medicine, Detroit, MI, 48201, USA
| | - Karin Przyklenk
- Department of Emergency Medicine, Wayne State University School of Medicine, Detroit, MI, 48201, USA
- Cardiovascular Research Institute, Wayne State University School of Medicine, Detroit, MI, 48201, USA
- Department of Physiology, Wayne State University School of Medicine, Detroit, MI, 48201, USA
| | - Thomas H Sanderson
- Department of Emergency Medicine, Wayne State University School of Medicine, Detroit, MI, 48201, USA.
- Cardiovascular Research Institute, Wayne State University School of Medicine, Detroit, MI, 48201, USA.
- Department of Physiology, Wayne State University School of Medicine, Detroit, MI, 48201, USA.
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Anzell AR, Potteiger JA, Kraemer WJ, Otieno S. Changes in height, body weight, and body composition in American football players from 1942 to 2011. J Strength Cond Res 2013; 27:277-84. [PMID: 23222088 DOI: 10.1519/jsc.0b013e31827f4c08] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The purpose of this study was to document changes in height (cm), body weight (kg), and body composition (%fat) of American football players from 1942 to 2011. Published articles were identified from databases and cross-referencing of bibliographies. Studies selected met the requirements of (1) having 2 of 3 dependent (height, body weight, and body composition) variables reported in the results; (2) containing a skill level of college or professional; (3) providing measured not self-reported data; and (4) published studies in English language journals. The data were categorized into groups based on skill level (college and professional). The player positions were grouped into 3 categories: mixed linemen (offensive and defensive linemen, tight ends, and linebackers), mixed offensive backs (quarterback and running backs), and mixed skilled positions (defensive backs and wide receivers). Linear regression was used to provide slope estimates and 95% confidence intervals (CIs). Unpaired t-tests were used to determine whether an individual regression slope was significantly different from zero. Statistical significance was set at p < 0.017. College level players in all position groups have significantly increased body weight over time (95% CI: mixed lineman 0.338-0.900 kg·y(-1); mixed offensive backs 0.089-0.298 kg·y(-1); mixed skilled 0.078-0.334 kg·y(-1)). The college level mixed linemen showed a significant increase over time for height (95% CI: 0.034-0.188 cm·y(-1)) and body composition (0.046-0.275% fat per year). Significant increases in body weight over time were found for professional level mixed lineman (95% CI: 0.098-0.756 kg·y(-1)) and mixed offensive backs (95% CI: 0.1800-0.545 kg·y(-1)). There were no other significant changes at the professional level. These data demonstrate that body weight of all college players and professional mixed lineman have significantly increased from 1942 to 2011.
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Affiliation(s)
- Anthony R Anzell
- Department of Biomedical Sciences, Grand Valley State University, Grand Rapids, Michigan, USA
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