Maturation and degeneration of the human brainstem across the adult lifespan.
Aging (Albany NY)
; 13(11): 14862-14891, 2021 06 11.
Article
en En
| MEDLINE
| ID: mdl-34115614
Brainstem tissue microstructural properties change across the adult lifespan. However, studies elucidating the biological processes that govern brainstem maturation and degeneration in-vivo are lacking. In the present work, conducted on a large cohort of 140 cognitively unimpaired subjects spanning a wide age range of 21 to 94 years, we implemented a multi-parameter approach to characterize the sex- and age differences. In addition, we examined regional correlations between myelin water fraction (MWF), a direct measure of myelin content, and diffusion tensor imaging indices, and transverse and longitudinal relaxation rates to evaluate whether these metrics provide information complementary to MWF. We observed region-dependent differences in myelin content and axonal density with age and found that both exhibit an inverted U-shape association with age in several brainstem substructures. We emphasize that the microstructural differences captured by our distinct MRI metrics, along with their weak associations with MWF, strongly indicate the potential of using these outcome measures in a multi-parametric approach. Furthermore, our results support the gain-predicts-loss hypothesis of tissue maturation and degeneration in the brainstem. Indeed, our results indicate that myelination follows a temporally symmetric time course across the adult life span, while axons appear to degenerate significantly more rapidly than they mature.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Banco de datos:
MEDLINE
Asunto principal:
Tronco Encefálico
/
Longevidad
Tipo de estudio:
Etiology_studies
/
Incidence_studies
/
Observational_studies
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Prognostic_studies
/
Risk_factors_studies
Límite:
Adult
/
Aged
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Aged80
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Female
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Humans
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Male
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Middle aged
Idioma:
En
Revista:
Aging (Albany NY)
Asunto de la revista:
GERIATRIA
Año:
2021
Tipo del documento:
Article
País de afiliación:
Estados Unidos