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Methods to Quantify Pharmacologically Induced Alterations in Motor Function in Human Incomplete SCI
Published on: April 18, 2011
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Spinal motor neurons and motor function in older adults
Aron S Buchman1,2, Sue E Leurgans3,4, Veronique G J M VanderHorst5,6
1Rush Alzheimer's Disease Center, Rush University Medical Center, Jelke Building, Suite #1000; 1750 West Harrison Street, Chicago, IL, 60612, USA. aron_s_buchman@rush.edu.
Journal of Neurology
|November 18, 2018
Summary
Spinal motor neuron (SMN) counts predict motor function in older men near death, but not women. Activated spinal microglia correlate with lower SMN, suggesting a role in motor decline.
Area of Science:
- Neuroscience
- Gerontology
- Neuropathology
Background:
- Motor function declines with age, impacting older adults' quality of life.
- Spinal motor neurons (SMNs) are crucial for motor control, and their loss is implicated in age-related motor impairments.
- Understanding factors affecting SMNs near death is vital for addressing mobility issues in the elderly.
Purpose of the Study:
- To investigate the relationship between lumbar spinal motor neuron (SMN) indices and motor function in community-dwelling older adults near the end of life.
- To determine if sex influences the association between SMN counts and motor performance.
- To explore the link between neuroinflammation, specifically activated microglia, and SMN integrity.
Main Methods:
- Utilized data from 145 older adults in the Rush Memory and Aging Project, including clinical motor testing and post-mortem spinal cord examination.
- Quantified spinal motor neurons (SMNs) and ventral horn area using choline acetyltransferase immunostaining in the L4/5 spinal cord segment.
- Employed linear regression modeling, including sex-stratified analyses and controlling for brain pathologies and chronic health conditions, to analyze associations.
Main Results:
- The association between SMN counts/density and global motor scores near death significantly differed between men and women.
- Higher SMN counts and density were linked to better motor function in men, but not in women.
- Increased counts of activated spinal microglia were associated with lower SMN counts, suggesting a neuroinflammatory component.
Conclusions:
- Spinal motor neuron integrity is associated with motor function in older men proximate to death.
- Sex-specific differences exist in the relationship between spinal motor neurons and motor performance.
- Activated spinal microglia and the loss of spinal motor neurons may contribute to motor impairments observed in older men.
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