Locomotor training with adjuvant testosterone preserves cancellous bone and promotes muscle plasticity in male rats after severe spinal cord injury.

Autor: Yarrow JF; Research Service, Malcom Randall Department of Veterans Affairs Medical Center, North Florida/South Georgia Veterans Health System, Gainesville, FL, USA.; Brain Rehabilitation Research Center, Malcom Randall Department of Veterans Affairs Medical Center, North Florida/South Georgia Veterans Health System, Gainesville, FL, USA.; Division of Endocrinology, Diabetes, and Metabolism, University of Florida College of Medicine, Gainesville, FL, USA., Kok HJ; Research Service, Malcom Randall Department of Veterans Affairs Medical Center, North Florida/South Georgia Veterans Health System, Gainesville, FL, USA.; Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, FL, USA., Phillips EG; Research Service, Malcom Randall Department of Veterans Affairs Medical Center, North Florida/South Georgia Veterans Health System, Gainesville, FL, USA., Conover CF; Research Service, Malcom Randall Department of Veterans Affairs Medical Center, North Florida/South Georgia Veterans Health System, Gainesville, FL, USA., Lee J; Research Service, Malcom Randall Department of Veterans Affairs Medical Center, North Florida/South Georgia Veterans Health System, Gainesville, FL, USA., Bassett TE; Research Service, Malcom Randall Department of Veterans Affairs Medical Center, North Florida/South Georgia Veterans Health System, Gainesville, FL, USA., Buckley KH; Research Service, Malcom Randall Department of Veterans Affairs Medical Center, North Florida/South Georgia Veterans Health System, Gainesville, FL, USA., Reynolds MC; Research Service, Malcom Randall Department of Veterans Affairs Medical Center, North Florida/South Georgia Veterans Health System, Gainesville, FL, USA., Wnek RD; Research Service, Malcom Randall Department of Veterans Affairs Medical Center, North Florida/South Georgia Veterans Health System, Gainesville, FL, USA., Otzel DM; Brain Rehabilitation Research Center, Malcom Randall Department of Veterans Affairs Medical Center, North Florida/South Georgia Veterans Health System, Gainesville, FL, USA., Chen C; Divison of Orthopedics and Rehabilitation, University of Florida College of Medicine, Gainesville, FL, USA., Jiron JM; Department of Physiological Sciences, University of Florida, Gainesville, FL, USA., Graham ZA; National Center for the Medical Consequences of Spinal Cord Injury, James J. Peters Veterans Affairs Medical Center, Bronx, NY, USA.; Departments of Medicine, Icahn School of Medicine, New York, NY, USA., Cardozo C; National Center for the Medical Consequences of Spinal Cord Injury, James J. Peters Veterans Affairs Medical Center, Bronx, NY, USA.; Departments of Medicine, Icahn School of Medicine, New York, NY, USA.; Rehabilitation Medicine, Icahn School of Medicine, New York, NY, USA., Vandenborne K; Department of Physical Therapy, University of Florida, Gainesville, FL, USA., Bose PK; Brain Rehabilitation Research Center, Malcom Randall Department of Veterans Affairs Medical Center, North Florida/South Georgia Veterans Health System, Gainesville, FL, USA.; Department of Physiological Sciences, University of Florida, Gainesville, FL, USA.; Division of Neurology, University of Florida College of Medicine, Gainesville, FL, USA., Aguirre JI; Department of Physiological Sciences, University of Florida, Gainesville, FL, USA., Borst SE; Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, FL, USA., Ye F; Research Service, Malcom Randall Department of Veterans Affairs Medical Center, North Florida/South Georgia Veterans Health System, Gainesville, FL, USA.
Jazyk: angličtina
Zdroj: Journal of neuroscience research [J Neurosci Res] 2020 May; Vol. 98 (5), pp. 843-868. Date of Electronic Publication: 2019 Dec 04.
DOI: 10.1002/jnr.24564
Abstrakt: Loading and testosterone may influence musculoskeletal recovery after spinal cord injury (SCI). Our objectives were to determine (a) the acute effects of bodyweight-supported treadmill training (TM) on hindlimb cancellous bone microstructure and muscle mass in adult rats after severe contusion SCI and (b) whether longer-term TM with adjuvant testosterone enanthate (TE) delivers musculoskeletal benefit. In Study 1, TM (40 min/day, 5 days/week, beginning 1 week postsurgery) did not prevent SCI-induced hindlimb cancellous bone loss after 3 weeks. In Study 2, TM did not attenuate SCI-induced plantar flexor muscles atrophy nor improve locomotor recovery after 4 weeks. In our main study, SCI produced extensive distal femur and proximal tibia cancellous bone deficits, a deleterious slow-to-fast fiber-type transition in soleus, lower muscle fiber cross-sectional area (fCSA), impaired muscle force production, and levator ani/bulbocavernosus (LABC) muscle atrophy after 8 weeks. TE alone (7.0 mg/week) suppressed bone resorption, attenuated cancellous bone loss, constrained the soleus fiber-type transition, and prevented LABC atrophy. In comparison, TE+TM concomitantly suppressed bone resorption and stimulated bone formation after SCI, produced near-complete cancellous bone preservation, prevented the soleus fiber-type transition, attenuated soleus fCSA atrophy, maintained soleus force production, and increased LABC mass. 75% of SCI+TE+TM animals recovered voluntary over-ground hindlimb stepping, while no SCI and only 20% of SCI+TE animals regained stepping ability. Positive associations between testosterone and locomotor function suggest that TE influenced locomotor recovery. In conclusion, short-term TM alone did not improve bone, muscle, or locomotor recovery in adult rats after severe SCI, while longer-term TE+TM provided more comprehensive musculoskeletal benefit than TE alone.
(Published 2019. This article is a U.S. Government work and is in the public domain in the USA.)
Databáze: MEDLINE
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