Low-Frequency Pulsed Electromagnetic Fields May Improve Spinal Cord Injury Recovery

by | Jan 13, 2020 | 2019, Alternative Therapies, EMF's

Written by Angeline A. De Leon, Staff Writer.  Low‑frequency pulsed electromagnetic fields support functional recovery following spinal cord injury by potentially modulating inflammation, oxidative stress and heat shock protein levels.

bone healthSpinal cord injury (SCI) involves damage to the spinal cord and subsequent disruption of the communication between the body and central nervous system 1. SCI may be characterized by a two-stage pathological process, involving a primary injury (immediate damage following SCI) and secondary injury, which includes a cascade of pathological changes that develop after the initial injury 2. Secondary injuries typically involve swelling and hemorrhage, which lead to increased levels of inflammation (greater expression of pro-inflammatory factors like tumor necrosis factor-α, TNF-α, and interleukin-1β, IL-1β) and oxidative stress (elevation of nitric oxide, NO, and reactive oxygen species, ROS) 3. Recent findings have uncovered the clinical utility of low-frequency pulsed electromagnetic fields (LPEMFs) in mitigating inflammation and oxidative stress 4 and promoting anti-oxidative responses 5. In in vitro models of neurodegenerative disease, LPEMFs have been shown to stimulate tissue regeneration 6 and have been used to promote recovery in stroke patients by increasing levels of brain-derived neurotrophic factors 7. Newer research also indicates that ultra low-frequency magnetic fields may protect against SCI-related tissue damage 8. To determine whether LPEMFs can effectively inhibit secondary SCI injury, researchers in China (2019) investigated the effects of LPEMF treatment on inflammation and oxidative stress levels in a rat model of SCI 9.

A group of 60 adult female Wistar rats were randomly assigned to one of three groups: a sham group (no SCI induced); a SCI group receiving spinal cord contusion injury at vertebrae T10; or an LPEMF group receiving LPEMF treatment (frequency = 50 Hz, power = 2.5mT, duty cycle = 40%) for one hour daily for 14 days 24 hours following SCI. Functional recovery was tested using the Basso Beattie Bresnahan (BBB) locomotor rating scale. Animals were sacrificed on Days 3, 7, and 14 following SCI, and spinal cords were harvested and analyzed for markers of inflammation (TNF-α; IL-1β; nuclear factor kB, NF-kB) and oxidative stress (inducible NOS, iNOS; ROS; superoxide dismutase, SOD; catalase, CAT) using protein assays and Western blot analysis. Levels of heat shock protein 70 (HSP70, involved in protein folding and protection against cellular stress) were also assessed using immunohistochemistry analysis.

From Day 7 to Day 14, rats in the LPEMF group demonstrated significantly better motor function recovery than SCI rats, based on BBB scores (p < 0.05). At the end of two weeks, protein expressions of TNF-α and IL-1β were found to be significantly lower in the LPEMF group, relative to SCI (p < 0.05 for both), and LPEMF was associated with significantly reduced immunoreactivity of NF-kB in the injured spinal cord, compared to the SCI group (p < 0.05). Relative to SCI, LPEMF treatment was also linked to suppressed iNOS expression and reduced ROS production (p < 0.05 for both), as well as upregulated expression of SOD and CAT (p < 0.05 for both), suggesting a protective effect on antioxidant enzymes. Finally, LPEMF rats were found to have significantly increased expression of HSP70 in their motor neurons, compared to SCI rats (p < 0.05).

As the first study of LPEMF treatment in a contusion SCI model, findings provide support for the role of LPEMF in the alleviation of secondary SCI injuries and promotion of functional recovery. LPEMF was associated with general improvement in locomotor function, as well as marked diminishment of inflammation and oxidative stress. Researchers hypothesize that the ability of LPEMF to modulate inflammation and oxidative stress levels may be related to the activation of HSP70, which was observed in the current study. Additional studies are needed to confirm a causal link and to extrapolate findings to human subjects. Overall, however, evidence points to the therapeutic value of LPEMF as a promising, non-invasive approach to treating SCI.

Source: Wang C, Liu Y, Wang Y, et al. Low-frequency pulsed electromagnetic field promotes functional recovery, reduces inflammation and oxidative stress, and enhances HSP70 expression following spinal cord injury. Molecular Medicine Reports. 2019; 19: 1687-1693.  DOI: 10.3892/mmr.2019.9820.

© This study is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0) License.

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Posted January 13, 2020.

Angeline A. De Leon, MA, graduated from the University of Illinois at Urbana-Champaign in 2010, completing a bachelor’s degree in psychology, with a concentration in neuroscience. She received her master’s degree from The Ohio State University in 2013, where she studied clinical neuroscience within an integrative health program. Her specialized area of research involves the complementary use of neuroimaging and neuropsychology-based methodologies to examine how lifestyle factors, such as physical activity and meditation, can influence brain plasticity and enhance overall connectivity.

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