Abstract Body: Background and Objective: The effects of noninvasive focused nanomagnetic brain stimulation (MagStim) on post-stroke motor deficits and metabolic dormancy in subacute ischemic injury is not well-established. This study examines the therapeutic actions of MagStim for enhancing motor recovery after stroke.
Methods: We administered focused MagStim for 30 minutes daily following a magnetic nanoparticles (MNP) injection (15mg/mL) into the targeted motor cortex subsequent to three weeks of middle cerebral artery occlusion (MCAO). Behavioral tests for motor functionality and PET imaging for cerebral metabolic activity were conducted. Additional assessments included cortical hyperexcitability, neuroinflammation, blood-brain-barrier (BBB) integrity, and neurogenesis at four weeks post-stroke, according to the treatment groups (Control, MNP injection only, and MagStim).
Results: The MagStim group exhibited significant improvements in motor deficits and cerebral metabolic activity compared to the Control and MNP groups (p < 0.05). Focused MagStim modulated cortical excitability, evident by an elevated action potential threshold for spike initiation and reduced firing frequency post-stroke. The MagStim group also demonstrated markedly decreased levels of inflammatory markers such as IL-1β, IL-6, TNF-α, MCP-1, and ICAM-1 in comparison to the Control and MNP groups. Markers of BBB integrity and immunofluorescence for neurogenesis were substantially improved in the MagStim group.
Conclusions: Our findings reveal that focused MagStim facilitates the recovery of motor deficits and metabolic inactivity in the brain by effectively modulating excitability, reducing neuroinflammation, enhancing BBB stability, and promoting neurogenesis. MagStim emerges as a potential novel and noninvasive therapy for stroke rehabilitation, warranting further investigation.