Exercise Ameliorates Spinal Cord Injury by Changing DNA Methylation

Area of Science:

• Neuroscience
• Epigenetics
• Rehabilitation Medicine

Background:

• Spinal cord injury (SCI) impairs motor function, with exercise being a potential therapeutic strategy.
• The precise mechanisms underlying exercise-induced recovery after SCI remain largely unknown.
• Previous research indicated that epigenetic modifications in the brain motor cortex can promote functional recovery post-SCI.

Purpose of the Study:

• To investigate the functional effects of treadmill exercise in a rat model of SCI.
• To determine if epigenetic alterations in the brain motor cortex are involved in exercise-mediated recovery.
• To elucidate the mechanisms by which exercise impacts SCI recovery.

Main Methods:

• A spinal cord contusion model was established in rats.
• Rats underwent 12 weeks of treadmill exercise.
• Lesion size, macrophage presence, DNA methylation (5mC, 5hmC) levels, ten-eleven translocation (Tet) gene expression, and locomotor function (BBB and ladder scores) were assessed.

Main Results:

• Exercise significantly reduced lesion cavity size and macrophage count.
• Increased levels of 5-methylcytosine (5mC) and 5-hydroxymethylcytosine (5hmC) were observed in the motor cortex of exercising rats.
• Expression of Tet1, Tet2, and Tet3 genes in the motor cortex was elevated following exercise.
• Locomotor function, assessed by BBB and ladder scores, showed significant improvement in the exercise group.

Conclusions:

• Treadmill exercise promotes functional recovery in rats with SCI.
• Epigenetic modifications, including changes in DNA methylation and hydroxymethylation in the brain motor cortex, are implicated in exercise-induced improvements.
• Exercise may offer a therapeutic benefit for SCI by modulating epigenetic pathways.