Background: Iron oxide nanoparticles (IONPs) can attenuate oxidative stress in a neutral pH environment in vitro. In combination with an external electromagnetic field, they can also facilitate axon regeneration. The present study demonstrates the in vivo potential of IONPs to recover functional deficits in rats with complete spinal cord injury. Methods: The spinal cord was completely transected at the T11 vertebra in male albino Wistar rats. Iron oxide nanoparticle solution (25 µg/mL) embedded in 3% agarose gel was implanted at the site of transection, which was subsequently exposed to an electromagnetic field (50 Hz, 17.96 µT for two hours daily for five weeks). Results: Locomotor and sensorimotor assessment as well as histological analysis demonstrated significant functional recovery and a reduction in lesion volume in rats with IONP implantation and exposure to an electromagnetic field. No collagenous scar was observed and IONPs were localized intracellularly in the immediate vicinity of the lesion. Further, in vitro experiments to explore the cytotoxic effects of IONPs showed no effect on cell survival. However, a significant decrease in H2O2-mediated oxidative stress was evident in the medium containing IONPs, indicating their free radical scavenging properties. Conclusion: These novel findings indicate a therapeutic role for IONPs in spinal cord injury and other neurodegenerative disorders mediated by reactive oxygen species.
Background: There is a crucial need to devise optimum rehabilitation programs for children with cerebral palsy (CP). Objective: This study aimed to assess the feasibility, safety, and efficacy of combining 6-Hz primed, low-frequency, repetitive transcranial magnetic stimulation (rTMS) with modified constraint-induced movement therapy (mCIMT) in improving upper limb function in children with unilateral CP. Methods: Children aged 5 to 18 years with unilateral CP were randomized (23 in each arm) to receive 10 sessions of mCIMT with real rTMS (intervention arm) or mCIMT with sham rTMS (control arm), on alternate weekdays over 4 weeks. The primary outcome was the difference in mean change in Quality of Upper Extremity Skills Test (QUEST) scores. Secondary outcomes were changes in QUEST domain scores, speed and strength measures, CP quality of life (CP-QOL) scale scores, and safety of rTMS. Results: All 46 children completed the trial except one. At 4 weeks, the mean change in total QUEST scores was significantly higher in the intervention arm as compared to the control arm (11.66 ± 6.97 vs 6.56 ± 4.3, d = 5.1, 95% CI 1.7-8.5, P = .004). Change in “weight bearing” and “protective extension” domain score was significantly higher for children in the intervention arm. These improvements were sustained at 12 weeks ( P = .028). CP-QOL scores improved at 12 weeks. No serious adverse events were seen. Conclusion: A 6-Hz primed rTMS combined with mCIMT is safe, feasible, and superior to mCIMT alone in improving the upper limb function of children with unilateral CP. Trial Registration: ClinicalTrials.gov Identifier: NCT03792789.
Magnetic field (MF) stimulation has the potential to reduce secondary damage and promote functional recovery after neural tissue injury. The study aimed to observe the effect of very low intensity (17.96µT) MF on general body condition, secondary damage, pain status, and locomotion. We exposed rats to MF (2 h/day × 3 weeks) after 6.25 mm contusion spinal injury. Locomotor behavior was evaluated by BBB score, pain assessment was done by recording threshold for tail flick, expression of voltage-gated calcium channels and extent of secondary damage in the spinal cord was assessed by immunofluorescence and Cresyl violet staining, respectively. A significant (p ≤ .001) improvement in bladder function as well as BBB score was observed after MF exposure in comparison with sham and SCI over the observation period of 3 weeks. SCI group showed an increase in the threshold for vocalization after discharge, which decreased following MF exposure. Cresyl violet staining showed significantly higher tissue sparing (73%) at the epicenter after MF exposure when compared to SCI group. This was accompanied with a significant decrease in calcium channel expression in MF group as compared to SCI. The results suggest facilitation of sensory-motor recovery after MF exposure, which could be due to attenuation of secondary damage and calcium-mediated excitotoxicity in a mild contusion rat model of SCI.