DI-5-Cuffs: Lumbar Intervertebral Disc Proteoglycan and Water Content Changes in Humans after Five Days of Dry Immersion to Simulate Microgravity.
Int J Mol Sci
; 21(11)2020 05 26.
Article
em En
| MEDLINE
| ID: mdl-32466473
ABSTRACT
Most astronauts experience back pain after spaceflight, primarily located in the lumbar region. Intervertebral disc herniations have been observed after real and simulated microgravity. Spinal deconditioning after exposure to microgravity has been described, but the underlying mechanisms are not well understood. The dry immersion (DI) model of microgravity was used with eighteen male volunteers. Half of the participants wore thigh cuffs as a potential countermeasure. The spinal changes and intervertebral disc (IVD) content changes were investigated using magnetic resonance imaging (MRI) analyses with T1-T2 mapping sequences. IVD water content was estimated by the apparent diffusion coefficient (ADC), with proteoglycan content measured using MRI T1-mapping sequences centered in the nucleus pulposus. The use of thigh cuffs had no effect on any of the spinal variables measured. There was significant spinal lengthening for all of the subjects. The ADC and IVD proteoglycan content both increased significantly with DI (7.34 ± 2.23% and 10.09 ± 1.39%, respectively; mean ± standard deviation), p < 0.05). The ADC changes suggest dynamic and rapid water diffusion inside IVDs, linked to gravitational unloading. Further investigation is needed to determine whether similar changes occur in the cervical IVDs. A better understanding of the mechanisms involved in spinal deconditioning with spaceflight would assist in the development of alternative countermeasures to prevent IVD herniation.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Proteoglicanas
/
Ausência de Peso
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Dor nas Costas
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Bandagens Compressivas
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Disco Intervertebral
Tipo de estudo:
Clinical_trials
/
Etiology_studies
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Prognostic_studies
Limite:
Adult
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Humans
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Male
Idioma:
En
Revista:
Int J Mol Sci
Ano de publicação:
2020
Tipo de documento:
Article
País de afiliação:
França