Decreased thin filament density and length in human atrophic soleus muscle fibers after spaceflight
Open accessAbstract
Soleus muscle fibers were examined electron microscopically from pre- and postflight biopsies of four astronauts orbited for 17 days during the Life and Microgravity Sciences Spacelab Mission (June 1996). Myofilament density and spacing were normalized to a 2.4-μm sarcomere length. Thick filament density (∼1,062 filaments/μm 2) and spacing (∼32.5 nm) were unchanged by spaceflight. Preflight thin filament density (2,976/μm 2) decreased significantly ( P < 0.01) to 2,215/μm 2 in the overlap A band region as a result of a 17% filament loss and a 9% increase in short filaments. Normal fibers had 13% short thin filaments. The 26% decrease in thin filaments is consistent with preliminary findings of a 14% increase in the myosin-to-actin ratio. Lower thin filament density was calculated to increase thick-to-thin filament spacing in vivo from 17 to 23 nm. Decreased density is postulated to promote earlier cross-bridge detachment and faster contraction velocity. Atrophic fibers may be more susceptible to sarcomere reloading damage, because force per thin filament is estimated to increase by 23%.
The claims and statistics of this paper haven’t been checked yet.
Run the check — free, no account needed. It reads the open-access text and checks the sources it cites.
Integrity signals
Registry
Cites
Statistics
Claims the paper makes
The claims and statistics of this paper haven’t been checked yet.
Run the check — free, no account needed. It reads the open-access text and checks the sources it cites.
Claims other papers make about this one
Each is checked against this paper’s own text: does it say what the citing paper says it does?
Evidence-based explanations for higher declines in muscle function are alterations in neural drive and changes in muscle fiber properties, such as thin filament density, yielding lower force per cross-sectional area.
“Evidence-based explanations for higher declines in muscle function (84) are alterations in neural drive and changes in muscle fiber properties, such as thin filament density (95) yielding lower force per cross-sectional area (84).”
From Nonuniform loss of muscle strength and atrophy during bed rest: a systematic review (2021) · cites this paper as [95]
Self-check
Percentages, sums and reported differences re-computed from the paper’s own numbers.
The self-check needs the paper’s full text.
Cites
Human fiber size and enzymatic properties after 5 and 11 days of spaceflight
Edgerton, V. R., Zhou, M. Y., Ohira, Y., Klitgaard, H., Jiang, B., Bell, G., Harris, B., Saltin, B., Gollnick, P. D., Roy, R. R., et al. (1995) · Journal of Applied Physiology · doi:10.1152/jappl.1995.78.5.1733 · Cited by 324 · see citing works
Flagged first, then by citations
Research works printed but not linked: 1
- Fitts RH, Riley DA, and Widrick JJ. Physiology of a micro- gravity environment invited review: microgravity and skeletal muscle. J Appl Physiol 89: 823-839, 2000.
Cited by
Sorted by citations
Disuse of the musculo-skeletal system in space and on earth
Narici, M. V., & de Boer, M. D. (2011) · European Journal of Applied Physiology · doi:10.1007/s00421-010-1556-x · Cited by 270 · see citing works
Circadian Rhythms, the Molecular Clock, and Skeletal Muscle
Harfmann, B. D., Schroder, E. A., & Esser, K. A. (2015) · Journal of Biological Rhythms · doi:10.1177/0748730414561638 · Cited by 211 · see citing works
Haun, C. T., Vann, C. G., Roberts, B. M., Vigotsky, A. D., Schoenfeld, B. J., & Roberts, M. D. (2019) · Frontiers in Physiology · doi:10.3389/fphys.2019.00247 · Cited by 192 · see citing works
Nonuniform loss of muscle strength and atrophy during bed rest: a systematic review
Marusic, U., Narici, M., Simunic, B., Pisot, R., & Ritzmann, R. (2021) · Journal of Applied Physiology · doi:10.1152/japplphysiol.00363.2020 · Cited by 185 · see citing works
Trappe, T. (2009) · Applied Physiology, Nutrition, and Metabolism · doi:10.1139/h09-041 · Cited by 56 · see citing works
Self-citationWISE-2005: Countermeasures to prevent muscle deconditioning during bed rest in women
Lee, S. M. C., Schneider, S. M., Feiveson, A. H., Macias, B. R., Smith, S. M., Watenpaugh, D. E., & Hargens, A. R. (2014) · Journal of Applied Physiology · doi:10.1152/japplphysiol.00590.2013 · Cited by 56 · see citing works
- Authors
- Riley, D. A., Bain, J. L. W., Thompson, J. L., Fitts, R. H., Widrick, J. J., Trappe, S. W., Trappe, T. A., & Costill, D. L.
- Affiliations
- Medical College of Wisconsin (US)
- Marquette University (US)
- Ball State University (US)
- Venue
- Journal of Applied Physiology
- Publisher
- American Physiological Society
- Published
- 2000-02-01
- Volume
- 88
- Issue
- 2
- Pages
- 567-572
- ISSN
- 0161-7567 (ISSN-L)
- 8750-7587
- 1522-1601
- OpenAlex
- W2155066004
- Cited by
- 119
- References
- 1
- Citations by year
- 2026: 6 · 2025: 2 · 2024: 1 · 2023: 3 · 2022: 2 · 2021: 7 · 2020: 2 · 2019: 7 · 2018: 4 · 2017: 7 · 2016: 4 · 2015: 11 · 2014: 7 · 2013: 4 · 2012: 3
- FWCI
- 3.81
- Type
- journal article
- Language
- en
- Open access
- Locations
- Journal of Applied Physiology (publishedVersion)
- PubMed (publishedVersion)
- e-Publications@Marquette (Marquette University) (submittedVersion)
- Funders
- National Aeronautics and Space Administration
- National Institutes of Health (5u01ns033472-04)
- National Institute of Neurological Disorders and Stroke (U01 NS-33472)
- Topics
- Health Sciences › Medicine › Physiology › Spaceflight effects on biology
- Life Sciences › Biochemistry, Genetics and Molecular Biology › Molecular Biology › Muscle Physiology and Disorders
- Physical Sciences › Engineering › Aerospace Engineering › Space Exploration and Technology
- Keywords
- spaceflight, microgravity, sarcomere length, cross-bridge detachment, contraction velocity, muscle atrophy, astronauts
- MeSH terms
- Humans, Male, Actin Cytoskeleton, Microscopy, Electron, Muscular Atrophy, Myofibrils, Sarcomeres, Space Flight, Weightlessness, Astronauts, Muscle, Skeletal, Muscle Fibers, Skeletal
About these checks
Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.
Statistics and arithmetic are recomputed, not judged.
Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.
What counts as a claim ›How we measure confidence ›How we check this ›
Are you an author, or do you see a problem with this page? Request a review
