» Articles » PMID: 24744911

Low Force Contractions Induce Fatigue Consistent with Muscle MRNA Expression in People with Spinal Cord Injury

Overview
Journal Physiol Rep
Specialty Physiology
Date 2014 Apr 19
PMID 24744911
Citations 19
Authors
Affiliations
Soon will be listed here.
Abstract

Spinal cord injury (SCI) is associated with muscle atrophy, transformation of muscle fibers to a fast fatigable phenotype, metabolic inflexibility (diabetes), and neurogenic osteoporosis. Electrical stimulation of paralyzed muscle may mitigate muscle metabolic abnormalities after SCI, but there is a risk for a fracture to the osteoporotic skeletal system. The goal of this study was to determine if low force stimulation (3 Hz) causes fatigue of chronically paralyzed muscle consistent with selected muscle gene expression profiles. We tested 29 subjects, nine with a SCI and 20 without and SCI, during low force fatigue protocol. Three SCI and three non-SCI subjects were muscle biopsied for gene and protein expression analysis. The fatigue index (FI) was 0.21 ± 0.27 and 0.91 ± 0.01 for the SCI and non-SCI groups, respectively, supporting that the low force protocol physiologically fatigued the chronically paralyzed muscle. The post fatigue potentiation index (PI) for the SCI group was increased to 1.60 ± 0.06 (P <0.001), while the non-SCI group was 1.26 ± 0.02 supporting that calcium handling was compromised with the low force stimulation. The mRNA expression from genes that regulate atrophy and fast properties (MSTN, ANKRD1, MYH8, and MYCBP2) was up regulated, while genes that regulate oxidative and slow muscle properties (MYL3, SDHB, PDK2, and RyR1) were repressed in the chronic SCI muscle. MSTN, ANKRD1, MYH8, MYCBP2 gene expression was also repressed 3 h after the low force stimulation protocol. Taken together, these findings support that a low force single twitch activation protocol induces paralyzed muscle fatigue and subsequent gene regulation. These findings suggest that training with a low force protocol may elicit skeletal muscle adaptations in people with SCI.

Citing Articles

GsMTx-4 combined with exercise improves skeletal muscle structure and motor function in rats with spinal cord injury.

Zhang X, Liu X, Li Q, Li C, Li X, Qian J PLoS One. 2025; 20(1):e0317683.

PMID: 39841686 PMC: 11753701. DOI: 10.1371/journal.pone.0317683.


Distinct Genomic Expression Signatures after Low-Force Electrically Induced Exercises in Persons with Spinal Cord Injury.

Petrie M, Suneja M, Shields R Int J Mol Sci. 2024; 25(18).

PMID: 39337673 PMC: 11432617. DOI: 10.3390/ijms251810189.


Low-frequency electrically induced exercise after spinal cord injury: Physiologic challenge to skeletal muscle and feasibility for long-term use.

Petrie M, Dudley-Javoroski S, Johnson K, Lee J, Dubey O, Shields R J Spinal Cord Med. 2024; 47(6):1026-1032.

PMID: 38619192 PMC: 11533229. DOI: 10.1080/10790268.2024.2338295.


Impaired Glucose Tolerance and Visceral Adipose Tissue Thickness among Lean and Non-Lean People with and without Spinal Cord Injury.

Kimball A, Petrie M, McCue P, Johnson K, Shields R J Funct Morphol Kinesiol. 2023; 8(3).

PMID: 37606417 PMC: 10443282. DOI: 10.3390/jfmk8030123.


Acute Low Force Electrically Induced Exercise Modulates Post Prandial Glycemic Markers in People with Spinal Cord Injury.

Petrie M, Kimball A, Shields R J Funct Morphol Kinesiol. 2022; 7(4).

PMID: 36278750 PMC: 9624321. DOI: 10.3390/jfmk7040089.


References
1.
Dudley-Javoroski S, Saha P, Liang G, Li C, Gao Z, Shields R . High dose compressive loads attenuate bone mineral loss in humans with spinal cord injury. Osteoporos Int. 2011; 23(9):2335-46. PMC: 3374128. DOI: 10.1007/s00198-011-1879-4. View

2.
Vandenboom R, Houston M . Phosphorylation of myosin and twitch potentiation in fatigued skeletal muscle. Can J Physiol Pharmacol. 1996; 74(12):1315-21. View

3.
Dudley-Javoroski S, Shields R . Assessment of physical function and secondary complications after complete spinal cord injury. Disabil Rehabil. 2006; 28(2):103-10. PMC: 3270309. DOI: 10.1080/09638280500163828. View

4.
Pedersen B . Muscle as a secretory organ. Compr Physiol. 2013; 3(3):1337-62. DOI: 10.1002/cphy.c120033. View

5.
Macintosh B, Holash R, Renaud J . Skeletal muscle fatigue--regulation of excitation-contraction coupling to avoid metabolic catastrophe. J Cell Sci. 2012; 125(Pt 9):2105-14. DOI: 10.1242/jcs.093674. View