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Chacko TP, Toole JT, Morris MC, Page J, Forsten RD, Barrett JP, Reinhard MJ, Brewster RC, Costanzo ME, Broderick G. A regulatory pathway model of neuropsychological disruption in Havana syndrome. Front Psychiatry 2023; 14:1180929. [PMID: 37965360 PMCID: PMC10642174 DOI: 10.3389/fpsyt.2023.1180929] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/06/2023] [Accepted: 09/29/2023] [Indexed: 11/16/2023] Open
Abstract
Introduction In 2016 diplomatic personnel serving in Havana, Cuba, began reporting audible sensory phenomena paired with onset of complex and persistent neurological symptoms consistent with brain injury. The etiology of these Anomalous Health Incidents (AHI) and subsequent symptoms remains unknown. This report investigates putative exposure-symptom pathology by assembling a network model of published bio-behavioral pathways and assessing how dysregulation of such pathways might explain loss of function in these subjects using data available in the published literature. Given similarities in presentation with mild traumatic brain injury (mTBI), we used the latter as a clinically relevant means of evaluating if the neuropsychological profiles observed in Havana Syndrome Havana Syndrome might be explained at least in part by a dysregulation of neurotransmission, neuro-inflammation, or both. Method Automated text-mining of >9,000 publications produced a network consisting of 273 documented regulatory interactions linking 29 neuro-chemical markers with 9 neuropsychological constructs from the Brief Mood Survey, PTSD Checklist, and the Frontal Systems Behavior Scale. Analysis of information flow through this network produced a set of regulatory rules reconciling to within a 6% departure known mechanistic pathways with neuropsychological profiles in N = 6 subjects. Results Predicted expression of neuro-chemical markers that jointly satisfy documented pathways and observed symptom profiles display characteristically elevated IL-1B, IL-10, NGF, and norepinephrine levels in the context of depressed BDNF, GDNF, IGF1, and glutamate expression (FDR < 5%). Elevations in CRH and IL-6 were also predicted unanimously across all subjects. Furthermore, simulations of neurological regulatory dynamics reveal subjects do not appear to be "locked in" persistent illness but rather appear to be engaged in a slow recovery trajectory. Discussion This computational analysis of measured neuropsychological symptoms in Havana-based diplomats proposes that these AHI symptoms may be supported in part by disruption of known neuroimmune and neurotransmission regulatory mechanisms also associated with mTBI.
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Affiliation(s)
- Thomas P. Chacko
- Center for Clinical Systems Biology, Rochester General Hospital, Rochester, NY, United States
| | - J. Tory Toole
- Center for Clinical Systems Biology, Rochester General Hospital, Rochester, NY, United States
| | - Matthew C. Morris
- Center for Clinical Systems Biology, Rochester General Hospital, Rochester, NY, United States
| | - Jeffrey Page
- Center for Clinical Systems Biology, Rochester General Hospital, Rochester, NY, United States
| | - Robert D. Forsten
- War Related Illness and Injury Study Center (WRIISC), Department of Veterans Affairs, Washington, DC, United States
| | - John P. Barrett
- War Related Illness and Injury Study Center (WRIISC), Department of Veterans Affairs, Washington, DC, United States
- Department of Preventive Medicine and Biostatistics, Uniformed Services University, Bethesda, MD, United States
| | - Matthew J. Reinhard
- War Related Illness and Injury Study Center (WRIISC), Department of Veterans Affairs, Washington, DC, United States
- Complex Exposures Threats Center, Department of Veterans Affairs, Washington, DC, United States
| | - Ryan C. Brewster
- War Related Illness and Injury Study Center (WRIISC), Department of Veterans Affairs, Washington, DC, United States
| | - Michelle E. Costanzo
- War Related Illness and Injury Study Center (WRIISC), Department of Veterans Affairs, Washington, DC, United States
- Complex Exposures Threats Center, Department of Veterans Affairs, Washington, DC, United States
- Department of Medicine, Uniformed Services University, Bethesda, MD, United States
| | - Gordon Broderick
- Center for Clinical Systems Biology, Rochester General Hospital, Rochester, NY, United States
- Complex Exposures Threats Center, Department of Veterans Affairs, Washington, DC, United States
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Keyan Z, Liqian Z, Xinzhong X, Juehua J, Chungui X. Pulsed Electromagnetic Fields Improved Peripheral Nerve Regeneration After Delayed Repair of One Month. Bioelectromagnetics 2023; 44:133-143. [PMID: 37277911 DOI: 10.1002/bem.22443] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2021] [Revised: 03/19/2023] [Accepted: 03/26/2023] [Indexed: 06/07/2023]
Abstract
The goal of this study was to determine if postoperative pulsed electromagnetic fields (PEMFs) could improve the neuromuscular rehabilitation after delayed repair of peripheral nerve injuries. Thirty-six Sprague-Dawley rats were randomly divided into sham group, control group, and PEMFs group. The sciatic nerves were transected except for the control group. One month later, the nerve ends of the former two groups were reconnected. PEMFs group of rats was subjected to PEMFs thereafter. Control group and sham group received no treatment. Four and 8 weeks later, morphological and functional changes were measured. Four and eight weeks postoperatively, compared to sham group, the sciatic functional indices (SFIs) of PEMFs group were higher. More axons regenerated distally in PEMFs group. The fiber diameters of PEMFs group were larger. However, the axon diameters and myelin thicknesses were not different between these two groups. The brain-derived neurotrophic factor and vascular endothelial growth factor expressions were higher in PEMFs group after 8 weeks. Semi-quantitative IOD analysis for the intensity of positive staining indicated that there were more BDNF, VEGF, and NF200 in PEMFs group. It's concluded that PEMFs have effect on the axonal regeneration after delayed nerve repair of one month. The upregulated expressions of BDNF and VEGF may play roles in this process. © 2023 Bioelectromagnetics Society.
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Affiliation(s)
- Zhu Keyan
- Department of Orthopaedics, The Second Affiliated Hospital of Anhui Medical University, Hefei, China
- Institute of Orthopaedics, Research Center for Translational Medicine, The Second Affiliated Hospital of Anhui Medical University, Hefei, China
| | - Zhang Liqian
- Department of Orthopaedics, The Second Affiliated Hospital of Anhui Medical University, Hefei, China
| | - Xu Xinzhong
- Department of Orthopaedics, The Second Affiliated Hospital of Anhui Medical University, Hefei, China
| | - Jing Juehua
- Department of Orthopaedics, The Second Affiliated Hospital of Anhui Medical University, Hefei, China
| | - Xu Chungui
- Department of Orthopaedics, The Second Affiliated Hospital of Anhui Medical University, Hefei, China
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Lee SY, Kim B, Lee SH, Ju K, Kim SM, Lee JH, Pang K. Biomechanical microenvironmental stimulating effect of pulsed electromagnetic field on the regeneration of crush injured rat sciatic nerve. Biomed Eng Lett 2023; 13:235-243. [PMID: 37124111 PMCID: PMC10130313 DOI: 10.1007/s13534-023-00276-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2023] [Revised: 03/21/2023] [Accepted: 04/03/2023] [Indexed: 05/02/2023] Open
Abstract
This study evaluated the biomechanical microenvironmental stimulating effect of pulsed electromagnetic field (PEMF) on the regeneration of crush-injured rat sciatic nerve, when combined with bone marrow mesenchymal stem cells (BMSCs) and recombinant human nerve growth factor (rhNGF-β), in the form of an adenoviral vector-mediated NGF. Sprague-Dawley rats were equally distributed into six groups; PBS, BMSC, NGF-Ad + BMSC, PEMF + PBS, PEMF + BMSC and PEMF + NGF-Ad + BMSC. The PBS group received PBS (volume: 10μL/rat), the BMSC group with BMSCs (1 × 106 cell/10 μL/rat) and NGF-Ad group with the rhNGF-β Ad infected BMSCs (1 × 106 cell/10 μL/rat) immediate after right sciatic nerve crush injury. The PEMF groups were exposed to PEMF of 1mT, 50 Hz, 1 h/day. The rats were observed for 3 weeks. PEMF alone did not showed the positive effect compared with negative control group. The groups transplanted with BMSCs showed higher axonal regeneration compared with the groups without transplantation of the cells whether BMSC was infected with NGF-Ad or not and whether the animals received PEMF. PEMF + NGF-Ad + BMSC group showed the significantly highest number of axons than the other groups. Functionally, all groups showed marked improvement at 3 weeks postoperatively although the difference was not statistically significant among the groups. PEMF showed the positive effect when combined with BMSC and NGF-ad in aspect of number of axons. Therefore, combining the microenvironment stimulation methods of PEMF and conventional methods such as transplantation of stem cells and growth factor could be considered for the regeneration methods in the nerve damage.
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Affiliation(s)
- Sang-Yoon Lee
- Dental Research Institute, Department of Oral and Maxillofacial Surgery, Seoul National University School of Dentistry, Seoul, Republic of Korea
| | - Bongju Kim
- Dental Life Science Research Institute, Innovation Research and Support Center for Dental Science, Seoul National University Dental Hospital, Seoul, Republic of Korea
| | - Sung-Ho Lee
- Dental Life Science Research Institute, Innovation Research and Support Center for Dental Science, Seoul National University Dental Hospital, Seoul, Republic of Korea
| | - Kyungwon Ju
- Dental Life Science Research Institute, Innovation Research and Support Center for Dental Science, Seoul National University Dental Hospital, Seoul, Republic of Korea
| | - Soung-Min Kim
- Department of Oral and Maxillofacial Surgery, Seoul National University School of Dentistry, Seoul, Republic of Korea
| | - Jong-Ho Lee
- Dental Life Science Research Institute, Innovation Research and Support Center for Dental Science, Seoul National University Dental Hospital, Seoul, Republic of Korea
- Oral Oncology Clinic, National Cancer Center, Il-San, Goyang-si, Republic of Korea
| | - KangMi Pang
- Department of Oral and Maxillofacial Surgery, Seoul National University Gwanak Dental Hospital, 1, Gwanak-Ro, Gwanak-Gu, Seoul, 08826 Republic of Korea
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Bademoğlu G, Erdal N, Uzun C, Taşdelen B. The effects of pulsed electromagnetic field on experimentally induced sciatic nerve injury in rats. Electromagn Biol Med 2021; 40:408-419. [PMID: 33797305 DOI: 10.1080/15368378.2021.1907403] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Some experimental research indicates that low-frequency pulsed electromagnetic field (PEMF) stimulation may accelerate regeneration in sciatic nerve injury. However, little research has examined the electrophysiological and functional properties of regenerating peripheral nerves under PEMF. The main aim of the present study is to investigate the effects of PEMF on sciatic nerve regeneration in short- and long-term processes with electrophysiologically and functionally after crushing damage. Crush lesions were performed using jewelery forceps for 30 s. After crush injury of the sciatic nerves, 24 female Wistar-Albino rats were divided into 3 groups with 8 rats in each group: SH(Sham), SNI (Sciatic Nerve Injury), SNI+PEMF(Sciatic Nerve Injury+Pulsed Electromagnetic Field). SNI+PEMF group was exposed to PEMF (4 h/day, intensity; 0.3mT, low-frequency; 2 Hz) for 40-days. Electrophysiological records (at the beginning and 1st, 2nd, 4th and 6th weeks post-crush) and functional footprints (at 1st, 2nd, 3rd, 4th, 5th and 6th weeks post crush) were measured from all groups during the experiment. The results were compared to SNI and SNI+PEMF groups, it was found that amplitude and area parameters in the first-week were significantly higher and latency was lower in the SNI+PEMF group than in the SNI group (p < 0,05). However, the effect of PEMF was not significant in the 2nd, 4th, 6th weeks. In addition, in the 1st and 2nd weeks, the SSI parameters were significantly higher in SNI+PMF group than SNI group (p < .05). These results indicate that low-frequency PEMF is not effective for long-periods of application time while PEMF may be useful during the short-term recovery period.
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Affiliation(s)
- Gülten Bademoğlu
- Department of Biophysics, Faculty of Medicine, Mersin University, Mersin, Turkey
| | - Nurten Erdal
- Department of Biophysics, Faculty of Medicine, Mersin University, Mersin, Turkey
| | - Coşar Uzun
- Department of Biophysics, Faculty of Medicine, Mersin University, Mersin, Turkey
| | - Bahar Taşdelen
- Department of Biostatistics and Medical Informatics, Faculty of Medicine, Mersin University, Mersin, Türkiye
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Riancho J, Sanchez de la Torre JR, Paz-Fajardo L, Limia C, Santurtun A, Cifra M, Kourtidis K, Fdez-Arroyabe P. The role of magnetic fields in neurodegenerative diseases. INTERNATIONAL JOURNAL OF BIOMETEOROLOGY 2021; 65:107-117. [PMID: 32198562 DOI: 10.1007/s00484-020-01896-y] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2019] [Revised: 02/19/2020] [Accepted: 03/06/2020] [Indexed: 06/10/2023]
Abstract
The term neurodegenerative diseases include a long list of diseases affecting the nervous system that are characterized by the degeneration of different neurological structures. Among them, Alzheimer disease (AD), Parkinson disease (PD), and amyotrophic lateral sclerosis (ALS) are the most representative ones. The vast majority of cases are sporadic and results from the interaction of genes and environmental factors in genetically predisposed individuals. Among environmental conditions, electromagnetic field exposure has begun to be assessed as a potential risk factor for neurodegeneration. In this review, we discuss the existing literature regarding electromagnetic fields and neurodegenerative diseases. Epidemiological studies in AD, PD, and ALS have shown discordant results; thus, a clear correlation between electromagnetic exposure and neurodegeneration has not been demonstrated. In addition, we discuss the role of electromagnetic radiation as a potential non-invasive therapeutic strategy for some neurodegenerative diseases, particularly for PD and AD.
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Affiliation(s)
- Javier Riancho
- Service of Neurology, Hospital Sierrallana-IDIVAL, Barrio Ganzo s/n, 39300, Torrelavega, Spain.
- CIBERNED, Barcelona, Spain.
- Medicine and Psychiatry Department, University of Cantabria, Santander, Spain.
| | | | - Lucía Paz-Fajardo
- Service of Internal Medicine, Hospital Sierrallana, Torrelavega, Spain
| | - Cristina Limia
- Service of Internal Medicine, Hospital Sierrallana, Torrelavega, Spain
| | - Ana Santurtun
- Legal Medicine and Toxicology Unit, Department of Physiology and Pharmacology, University of Cantabria, Santander, Spain
| | - Michal Cifra
- Institute of Photonics and Electronics of the Czech Academy of Sciences, Chaberská 1014/57, 182 51, Prague, Czech Republic
| | - Kostas Kourtidis
- Department of Environmental Engineering, Democritus University of Thrace, 67100, Xanthi, Greece
- Environmental and Networking Technologies and Applications Unit (ENTA), Athena Research and Innovation Center, 67100, Xanthi, Greece
| | - Pablo Fdez-Arroyabe
- Geography and Planning Department, Geobiomet Research Group, University of Cantabria, Santander, Spain
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Azimzadeh M, Jelodar G. Alteration of testicular regulatory and functional molecules following long-time exposure to 900 MHz RFW emitted from BTS. Andrologia 2019; 51:e13372. [PMID: 31347712 DOI: 10.1111/and.13372] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2019] [Revised: 06/12/2019] [Accepted: 06/21/2019] [Indexed: 12/31/2022] Open
Abstract
The aim of this investigation was to evaluate changes in testosterone and some of the functional and regulatory molecules of testis such as P450scc, steroidogenic acute regulatory protein (StAR), tumour necrosis factor-α (TNF-α), interleukin-1α (IL-1α), interleukin-1β (IL-1β) and nerve growth factor (NGF) following exposure to 900 MHz radio frequency (RF). Thirty adult male Sprague Dawley rats (190 ± 20 g BW) were randomly classified in three equal groups, control (sham, without any exposure), short-time exposure (2 hr) (STE) and long-time exposure (4 hr) (LTE). The exposure was performed for 30 consecutive days. The testosterone level in both exposed groups was significantly less than control (p < .05). Level of TNF-α in both exposed groups was significantly greater than control (p < .05). IL-1α and NGF levels in LTE were significantly higher than the STE and control groups (p < .05). Level of IL-1β in LTE was significantly higher than control (p < .05). Expression of both P450scc and StAR mRNA was significantly down-regulated in both exposed groups compared to control (p < .05). Our results showed that RFW can affect testis and reproductive function through changes in factors, which are important during steroidogenesis, and also through changes in inflammatory factors, which regulate Leydig cell functions.
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Affiliation(s)
- Mansour Azimzadeh
- Department of Basic Science, School of Veterinary Medicine, Shiraz University, Shiraz, Iran
| | - Gholamali Jelodar
- Department of Basic Science, School of Veterinary Medicine, Shiraz University, Shiraz, Iran
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Malling ASB, Morberg BM, Wermuth L, Gredal O, Bech P, Jensen BR. The effect of 8 weeks of treatment with transcranial pulsed electromagnetic fields on hand tremor and inter-hand coherence in persons with Parkinson's disease. J Neuroeng Rehabil 2019; 16:19. [PMID: 30704504 PMCID: PMC6357382 DOI: 10.1186/s12984-019-0491-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2018] [Accepted: 01/23/2019] [Indexed: 12/05/2022] Open
Abstract
BACKGROUND Parkinson's disease (PD) tremor comprises asymmetric rest and postural tremor with unilateral onset. Tremor intensity can be amplified by stress and reduced by attention, and the medical treatment is complex. Mirror movements and unintentional synchronization of bimanual movements, possibly caused by insufficient inhibition of inter-hemispheric crosstalk, have been reported in PD, indicating a lag of lateralization. Potential neuroprotective effects of pulsed electromagnetic fields (PEMF) have been reported in-vitro and in rodents, as have influences of PEMF on human tremor. The aim was to investigate the effect of 8 weeks daily transcranial PEMF treatment (T-PEMF) of persons with PD on rest and postural hand tremor characteristics and on inter-hand coherence. METHODS Hand accelerations of 50 PD participants with uni- or bilateral tremor participating in a clinical trial were analysed. A rest and postural tremor task performed during serial subtraction was assessed before and after 8 weeks of T-PEMF (30 min/day, 50 Hz, ±50 V, 3 ms squared pulses) or placebo treatment (sham stimulation 30 min/day). Forty matched healthy persons (no treatment) were included as reference. Intensity and inter-hand coherence related measures were extracted. RESULTS The T-PEMF treatment decreased the inter-hand coherence in the PD group with unilateral postural tremor. The PD group with unilateral postural tremor was less clinically affected by the disease than the PD group with bilateral postural tremor. However, no differences between T-PEMF and placebo treatment on either intensity related or coherence related measures were found when all persons with PD were included in the analyses. The peak power decreased and the tremor intensity tended to decrease in both treatment groups. CONCLUSIONS Eight weeks of T-PEMF treatment decreased inter-hand coherence in the PD group with unilateral postural tremor, while no effects of T-PEMF treatment were found for the entire PD group. The unilateral postural tremor group was less clinically affected than the bilateral postural tremor group, suggesting that early treatment initiation may be beneficial. In theory, a reduced inter-hand coherence could result from a neuronal treatment response increasing inter-hemispheric inhibition. However, this requires further studies to determine. Studies of even longer treatment periods would be of interest. TRIAL REGISTRATION ClinicalTrials.gov , NCT02125032. Registered 29 April 2014, https://clinicaltrials.gov/ct2/show/NCT02125032?term=NCT02125032&rank=1.
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Affiliation(s)
- Anne Sofie Bøgh Malling
- Department of Neurology, Odense University Hospital, University of Southern Denmark, Odense, Denmark.
- Department of Clinical Research, University of Southern Denmark, Odense, Denmark.
| | - Bo Mohr Morberg
- Department of Neurology, Odense University Hospital, University of Southern Denmark, Odense, Denmark
- Department of Clinical Research, University of Southern Denmark, Odense, Denmark
| | - Lene Wermuth
- Department of Neurology, Odense University Hospital, University of Southern Denmark, Odense, Denmark
- Department of Clinical Research, University of Southern Denmark, Odense, Denmark
| | - Ole Gredal
- The Danish Rehabilitation Centre for Neuromuscular Diseases, Taastrup, Denmark
| | - Per Bech
- Psychiatric Research Unit, Psychiatric Centre North Zealand, University of Copenhagen, Hillerød, Denmark
| | - Bente Rona Jensen
- Department of Neurology, Odense University Hospital, University of Southern Denmark, Odense, Denmark
- Department of Clinical Research, University of Southern Denmark, Odense, Denmark
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Malling ASB, Morberg BM, Wermuth L, Gredal O, Bech P, Jensen BR. Effect of transcranial pulsed electromagnetic fields (T-PEMF) on functional rate of force development and movement speed in persons with Parkinson's disease: A randomized clinical trial. PLoS One 2018; 13:e0204478. [PMID: 30252895 PMCID: PMC6155540 DOI: 10.1371/journal.pone.0204478] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Accepted: 09/06/2018] [Indexed: 11/18/2022] Open
Abstract
Background Parkinson’s disease is caused by dopaminergic neurodegeneration resulting in motor impairments as slow movement speed and impaired balance and coordination. Pulsed electromagnetic fields are suggested to have neuroprotective effects, and could alleviate symptoms. Objective To study 1) effects of 8-week daily transcranial pulsed electromagnetic field treatment on functional rate of force development and movement speed during two motor tasks with different levels of complexity, 2) if treatment effects depend on motor performance at baseline. Methods Ninety-seven persons with Parkinson’s disease were randomized to active transcranial pulsed electromagnetic field (squared bipolar 3 ms pulses, 50 Hz) or placebo treatment with homebased treatment 30 min/day for 8 weeks. Functional rate of force development and completion time of a sit-to-stand and a dynamic postural balance task were assessed pre and post intervention. Participants were sub-grouped in high- and low-performers according to their baseline motor performance level. Repeated measure ANOVAs were used. Results Active treatment tended to improve rate of force development during chair rise more than placebo (P = 0.064). High-performers receiving active treatment improved rate of force development during chair rise more than high-performers receiving placebo treatment (P = 0.049, active/placebo: 11.9±1.1 to 12.5±1.9 BW/s ≈ 5% / 12.4±1.3 to 12.2±1.3 BW/s, no change). No other between-treatment-group or between-treatment-subgroup differences were found. Data on rate of force development of the dynamic balance task and completion times of both motor tasks improved but did not allow for between-treatment differentiation. Conclusion Treatment with transcranial pulsed electromagnetic fields was superior to placebo regarding functional rate of force development during chair rise among high-performers. Active treatment tended to increase functional rate of force development while placebo did not. Our results suggest that mildly affected persons with Parkinson’s disease have a larger potential for neural rehabilitation than more severely affected persons and indicate that early treatment initiation may be beneficial.
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Affiliation(s)
- Anne Sofie Bøgh Malling
- Department of Neurology, Odense University Hospital, University of Southern Denmark, Odense, Denmark
- Department of Clinical Research, University of Southern Denmark, Odense, Denmark
- * E-mail: (ASBM); (BRJ)
| | - Bo Mohr Morberg
- Department of Neurology, Odense University Hospital, University of Southern Denmark, Odense, Denmark
- Department of Clinical Research, University of Southern Denmark, Odense, Denmark
| | - Lene Wermuth
- Department of Neurology, Odense University Hospital, University of Southern Denmark, Odense, Denmark
- Department of Clinical Research, University of Southern Denmark, Odense, Denmark
| | - Ole Gredal
- The Danish Rehabilitation Centre for Neuromuscular Diseases, Taastrup, Denmark
| | - Per Bech
- Psychiatric Research Unit, Psychiatric Centre North Zealand, University of Copenhagen, Hillerød, Denmark
| | - Bente Rona Jensen
- Department of Neurology, Odense University Hospital, University of Southern Denmark, Odense, Denmark
- * E-mail: (ASBM); (BRJ)
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Seo N, Lee SH, Ju KW, Woo J, Kim B, Kim S, Jahng JW, Lee JH. Low-frequency pulsed electromagnetic field pretreated bone marrow-derived mesenchymal stem cells promote the regeneration of crush-injured rat mental nerve. Neural Regen Res 2018; 13:145-153. [PMID: 29451219 PMCID: PMC5840980 DOI: 10.4103/1673-5374.224383] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Bone marrow-derived mesenchymal stem cells (BMSCs) have been shown to promote the regeneration of injured peripheral nerves. Pulsed electromagnetic field (PEMF) reportedly promotes the proliferation and neuronal differentiation of BMSCs. Low-frequency PEMF can induce the neuronal differentiation of BMSCs in the absence of nerve growth factors. This study was designed to investigate the effects of low-frequency PEMF pretreatment on the proliferation and function of BMSCs and the effects of low-frequency PEMF pre-treated BMSCs on the regeneration of injured peripheral nerve using in vitro and in vivo experiments. In in vitro experiments, quantitative DNA analysis was performed to determine the proliferation of BMSCs, and reverse transcription-polymerase chain reaction was performed to detect S100 (Schwann cell marker), glial fibrillary acidic protein (astrocyte marker), and brain-derived neurotrophic factor and nerve growth factor (neurotrophic factors) mRNA expression. In the in vivo experiments, rat models of crush-injured mental nerve established using clamp method were randomly injected with low-frequency PEMF pretreated BMSCs, unpretreated BMSCs or PBS at the injury site (1 × 106 cells). DiI-labeled BMSCs injected at the injury site were counted under the fluorescence microscope to determine cell survival. One or two weeks after cell injection, functional recovery of the injured nerve was assessed using the sensory test with von Frey filaments. Two weeks after cell injection, axonal regeneration was evaluated using histomorphometric analysis and retrograde labeling of trigeminal ganglion neurons. In vitro experiment results revealed that low-frequency PEMF pretreated BMSCs proliferated faster and had greater mRNA expression of growth factors than unpretreated BMSCs. In vivo experiment results revealed that compared with injection of unpretreated BMSCs, injection of low-frequency PEMF pretreated BMSCs led to higher myelinated axon count and axon density and more DiI-labeled neurons in the trigeminal ganglia, contributing to rapider functional recovery of injured mental nerve. These findings suggest that low-frequency PEMF pretreatment is a promising approach to enhance the efficacy of cell therapy for peripheral nerve injury repair.
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Affiliation(s)
- NaRi Seo
- Department of Oral and Maxillofacial Surgery, Graduate School of Dentistry, Seoul National University; Dental Research Institute, Seoul National University, Seoul, South Korea
| | - Sung-Ho Lee
- Department of Oral and Maxillofacial Surgery, Seoul National University Dental Hospital; Dental Research Institute, Seoul National University, Seoul, South Korea
| | - Kyung Won Ju
- Department of Oral and Maxillofacial Surgery, Seoul National University Dental Hospital; Dental Research Institute, Seoul National University, Seoul, South Korea
| | - JaeMan Woo
- Department of Oral and Maxillofacial Surgery, Seoul National University Dental Hospital, Seoul, South Korea
| | - BongJu Kim
- Clinical Translational Research Center for Dental Science (CTRC), Seoul National University Dental Hospital, Seoul, South Korea
| | - SoungMin Kim
- Department of Oral and Maxillofacial Surgery, Graduate School of Dentistry, Seoul National University; Department of Oral and Maxillofacial Surgery, Seoul National University Dental Hospital, Seoul, South Korea
| | - Jeong Won Jahng
- Dental Research Institute, Seoul National University, Seoul, South Korea
| | - Jong-Ho Lee
- Department of Oral and Maxillofacial Surgery, Graduate School of Dentistry, Seoul National University; Department of Oral and Maxillofacial Surgery, Seoul National University Dental Hospital; Dental Research Institute, Seoul National University; Clinical Translational Research Center for Dental Science (CTRC), Seoul National University Dental Hospital, Seoul, South Korea
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Pulsed magnetic field treatment as antineuropathic pain therapy. Rev Neurosci 2017; 28:751-758. [DOI: 10.1515/revneuro-2017-0003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2017] [Accepted: 03/08/2017] [Indexed: 01/08/2023]
Abstract
AbstractNo satisfactory effective therapy is still available to treat trauma- or disease-induced neuropathic pain, and current available treatment options have several side effects. Pulsed magnetic field (PMF) treatments are receiving growing interest as a therapeutic approach for several neuronal diseases. Although the exact mechanism of action of PMF treatments is unknown, reported findings represent a promising alternative therapeutic choice for the management of neuropathic pain. PMF treatments can supply new strategies for the therapy of life-threatening neuropathic pain due to its antihyperglycemic, anti-inflammatory, antihyperalgesic, antiallodynic, and neuroimmunomodulatory actions. In this review, I summarized the several recent findings about antineuropathic actions of PMF treatment in experimental animals with neuropathic pain induced by disease and/or damage.
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Cichoń N, Olejnik AK, Miller E, Saluk J. The multipotent action of electromagnetic field. Biologia (Bratisl) 2016. [DOI: 10.1515/biolog-2016-0142] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Tulaci KG, Tuzuner A, Karadas Emir H, Tatar İ, Sargon MF, Tulaci T, Karadavut Y, Samim EE. The effect of tacrolimus on facial nerve injury: Histopathological findings in a rabbit model. Am J Otolaryngol 2016; 37:393-7. [PMID: 27465503 DOI: 10.1016/j.amjoto.2016.06.003] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2016] [Revised: 06/24/2016] [Accepted: 06/28/2016] [Indexed: 12/15/2022]
Abstract
HYPOTHESIS Tacrolimus helps healing of facial nerve injury. BACKGROUND Positive effects of tacrolimus on axon regeneration and healing of injured peripheral nerves (eg. sciatic nerve) have been reported in the literature. Tacrolimus may be an additional treatment method that could improve the nerve healing after surgical treatment of cut injury of facial nerve. METHODS 20 New Zealand rabbits were randomly separated into control and study groups of 10. In control group, no medical treatment was given after facial nerve anastomosis, and the animals were followed up for 2months. In the study group rabbits were given 1mg/kg/day tacrolimus subcutaneously for 2months after the facial nerve anastomosis. The histopathologic findings of axon regeneration like axon myelination were analyzed in both groups under electron and light microscopy. The data obtained in the groups were compared. RESULTS Greater axon diameters, thicker myelin sheaths, and higher total number of myelinated axons were found in the tacrolimus group, suggesting better regeneration in this group when compared to the control group. There was less vacuolar degeneration in the study group. All these findings suggest that tacrolimus positively affects healing after facial nerve anastomosis. CONCLUSION The results of this study indicate that tacrolimus has favorable effects on the healing process of the facial nerve after end-to-end anastomosis. Tacrolimus may be a promising agent in the future for nerve regeneration following traumatic facial paralysis surgery.
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Ross CL, Syed I, Smith TL, Harrison BS. The regenerative effects of electromagnetic field on spinal cord injury. Electromagn Biol Med 2016; 36:74-87. [DOI: 10.3109/15368378.2016.1160408] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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Hei WH, Kim S, Park JC, Seo YK, Kim SM, Jahng JW, Lee JH. Schwann-like cells differentiated from human dental pulp stem cells combined with a pulsed electromagnetic field can improve peripheral nerve regeneration. Bioelectromagnetics 2016; 37:163-174. [PMID: 26991921 DOI: 10.1002/bem.21966] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2015] [Accepted: 02/25/2016] [Indexed: 01/09/2023]
Abstract
The purpose of this study was to investigate the effect of Schwann-like cells combined with pulsed electromagnetic field (PEMF) on peripheral nerve regeneration. Schwann-like cells were derived from human dental pulp stem cells (hDPSCs) and verified with CD104, S100, glial fibrillary acidic protein (GFAP), laminin, and P75NTR immunocytochemistry. Gene expression of P75NTR and S100 were analyzed. Male Sprague-Dawley rats (200-250g, 6-week-old) were divided into seven groups (n = 10 each): control, sham, PEMF, hDPSCs, hDPSCs + PEMF, Schwann-like cells, Schwann-like cells + PEMF. Cells were transplanted (1 × 106 /10µl/rat) at crush-injury site or combined with PEMF (50 Hz, 1 h/day, 1 mT). Nerve regeneration was evaluated with functional test, histomorphometry and retrograde labelled neurons. Schwann-like cells expressed CD104, S100, GFAP, laminin, and p75 neurotrophin receptor (P75NTR ). P75NTR and S100 mRNA expression was highest in Schwann-like cells + PEMF group, which also showed increased Difference and Gap scores. Axons and retrograde labeled neurons increased in all treatment groups. Schwann-like cells, hDPSCs with or without PEMF, and PEMF only improved peripheral nerve regeneration. Schwann-like cells + PEMF showed highest regeneration ability; PEMF has additive effect on hDPSCs, Schwann-like cell in vitro and nerve regeneration ability after transplantation in vivo. Bioelectromagnetics. 37:163-174, 2016. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Wei-Hong Hei
- Department of Oral and Maxillofacial Surgery, School of Dentistry, Seoul National University, Seoul, Korea.,Key Laboratory of Oral Biomedical Engineering of Ministry of Education, School and Hospital of Stomatology, Wuhan University, Wuhan, China
| | - Soochan Kim
- Graduate School of Bio and Information Technology, Hankyong National University, Anseong-si, Kyonggi-do, Seoul, Korea
| | - Joo-Cheol Park
- Department of Oral Histology-Developmental Biology, School of Dentistry, Seoul National University, Seoul, Korea
| | - Young-Kwon Seo
- Dongguk Department of Medical Biotechnology, College of Life Science and Biotechnology, Dongguk University, Seoul, Korea
| | - Soung-Min Kim
- Department of Oral and Maxillofacial Surgery, School of Dentistry, Seoul National University, Seoul, Korea
| | - Jeong Won Jahng
- Dental Research Institute, Seoul National University, Seoul, Korea
| | - Jong-Ho Lee
- Department of Oral and Maxillofacial Surgery, School of Dentistry, Seoul National University, Seoul, Korea.,Dental Research Institute, Seoul National University, Seoul, Korea
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Hei WH, Byun SH, Kim JS, Kim S, Seo YK, Park JC, Kim SM, Jahng JW, Lee JH. Effects of electromagnetic field (PEMF) exposure at different frequency and duration on the peripheral nerve regeneration: in vitro and in vivo study. Int J Neurosci 2015; 126:739-48. [PMID: 26010211 DOI: 10.3109/00207454.2015.1054032] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
PURPOSE The purpose was to clarify the influence of frequency and exposure time of pulsed electromagnetic fields (PEMF) on the peripheral nerve regeneration. MATERIALS AND METHODS Immortalized rat Schwann cells (iSCs) (1 × 10(2)/well) were exposed at four different conditions in 1 mT (50 Hz 1 h/d, 50 Hz 12 h/d, 150 Hz 1 h/d and 150 Hz 12h/d). Cell proliferation, mRNA expression of S100 and brain-derived neurotrophic factor (BDNF) were analyzed. Sprague-Dawley rats (200-250 g) were divided into six groups (n = 10 each): control, sham, 50 Hz 1 h/d, 50 Hz 12 h/d, 150 Hz 1 h/d and 150 Hz 12 Hr/d. Mental nerve was crush-injured and exposed at four different conditions in 1 mT (50 Hz 1 Hr/d, 50 Hz 12 Hr/d, 150 Hz 1 h/d and 150 Hz 12 h/d). Nerve regeneration was evaluated with functional test, histomorphometry and retrograde labeling of trigeminal ganglion. RESULTS iSCs proliferation with 50 Hz, 1 h/d was increased from fourth to seventh day; mRNA expression of S100 and BDNF was significantly increased at the same condition from first week to third week (p < .05 vs. control); difference score was increased at the second and third week, and gap score was increased at the third under 50 Hz 1 h PEMF compared with control while other conditions showed no statistical meaning. Axon counts and retrograde labeled neurons were significantly increased under PEMF of four different conditions compared with control. Although there was no statistical difference, 50 Hz, 1 h PEMF showed highest regeneration ability than other conditions. CONCLUSION PEMF enhanced peripheral nerve regeneration, and that it may be due to cell proliferation and increase in BDNF and S100 gene expression.
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Affiliation(s)
- Wei-Hong Hei
- a Department of Oral and Maxillofacial Surgery, School of Dentistry , Seoul National University , Seoul , Korea
| | - Soo-Hwan Byun
- a Department of Oral and Maxillofacial Surgery, School of Dentistry , Seoul National University , Seoul , Korea
| | - Jong-Sik Kim
- b Department of Oral and Maxillofacial Surgery, Hallum Medical School , Sacred Kangdong hospital , Seoul , Korea
| | - Soochan Kim
- c Graduate School of Bio & Information Technology , Hankyong National University , Anseong-si, Kyonggi-do , Seoul , Korea
| | - Young-Kwon Seo
- d Research Institute of Biotechnology , Dongguk University , Seoul , Korea
| | - Joo-Cheol Park
- e Department of Oral Histology-Developmental Biology, School of Dentistry , Seoul National University , Seoul , Korea
| | - Soung-Min Kim
- a Department of Oral and Maxillofacial Surgery, School of Dentistry , Seoul National University , Seoul , Korea
| | - Jeong Won Jahng
- f Dental Research Institute , Seoul National University , Seoul , Korea
| | - Jong-Ho Lee
- a Department of Oral and Maxillofacial Surgery, School of Dentistry , Seoul National University , Seoul , Korea.,f Dental Research Institute , Seoul National University , Seoul , Korea
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Mert T, Altun İ, Celik A, Sürer T, Gunay I. Modulation of cytokine levels in ameliorative effects of pulsed magnetic field on an experimental model of Chronic Constriction Injury. Int J Radiat Biol 2015; 91:596-602. [DOI: 10.3109/09553002.2015.1031408] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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Tran MTD, Skovbjerg S, Arendt-Nielsen L, Bech P, Lunde M, Elberling J. Two of three patients with multiple chemical sensitivity had less symptoms and secondary hyperalgesia after transcranially applied pulsed electromagnetic fields. Scand J Pain 2014; 5:104-109. [PMID: 29913674 DOI: 10.1016/j.sjpain.2013.11.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2013] [Accepted: 11/16/2013] [Indexed: 10/25/2022]
Abstract
Background Multiple chemical sensitivity (MCS) is a chronic, disabling condition characterized by recurrent multisystem symptoms triggered by common airborne chemicals. Evidence points towards abnormal sensory processing in the central nervous system (CNS) as a likely pathophysiological mechanism. No effective treatment has yet been reported, but clinical observations suggest that as pulsed electromagnetic fields (PEMF) is a treatment for some CNS disorders (depression and chronic pain), it may also be a treatment modality for MCS. Methods In an open case study, the effects of PEMF were assessed in three MCS patients. All cases received 30 min daily treatment 5 days a week for 8 consecutive weeks. Symptoms and functional impairments related to MCS, depressive symptoms, and capsaicin-induced secondary punctate hyperalgesia were assessed at baseline and weekly until an 18-week follow-up. Results Two of the three cases showed considerable improvement on all measures of symptoms and functional impairments related to MCS in response to PEMF therapy. One case showed no improvement and during the treatment period was unexpectedly diagnosed with depression. Conclusion Our findings indicate potential benefits of PEMF therapy in MCS. Implication The therapeutic effect of PEMF in MCS needs to be investigated by a randomized placebo-controlled trial.
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Affiliation(s)
- Marie Thi Dao Tran
- The Danish Research Centre for Chemical Sensitivities, Department of Dermato-Allergology, Copenhagen University Hospital Gentofte, Ledreborg Allé 40, 2. th., DK-2820 Gentofte, Denmark
| | - Sine Skovbjerg
- The Danish Research Centre for Chemical Sensitivities, Department of Dermato-Allergology, Copenhagen University Hospital Gentofte, Ledreborg Allé 40, 2. th., DK-2820 Gentofte, Denmark
| | - Lars Arendt-Nielsen
- Center for Sensory-Motor Interaction, Department of Health Science and Technology, Aalborg University, Frederik Bajers Vej 7 D3, DK-9220 Aalborg, Denmark
| | - Per Bech
- Psychiatric Research Unit, Mental Health Centre North Zealand, Dyrehavevej 48, DK-3400 Hillerød, Denmark
| | - Marianne Lunde
- Psychiatric Research Unit, Mental Health Centre North Zealand, Dyrehavevej 48, DK-3400 Hillerød, Denmark
| | - Jesper Elberling
- The Danish Research Centre for Chemical Sensitivities, Department of Dermato-Allergology, Copenhagen University Hospital Gentofte, Ledreborg Allé 40, 2. th., DK-2820 Gentofte, Denmark
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Lekhraj R, Cynamon DE, DeLuca SE, Taub ES, Pilla AA, Casper D. Pulsed electromagnetic fields potentiate neurite outgrowth in the dopaminergic MN9D cell line. J Neurosci Res 2014; 92:761-71. [DOI: 10.1002/jnr.23361] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2013] [Revised: 11/07/2013] [Accepted: 12/06/2013] [Indexed: 11/09/2022]
Affiliation(s)
- Rukmani Lekhraj
- Department of Neurological Surgery; Montefiore Medical Center and the Albert Einstein College of Medicine; Bronx New York
| | - Deborah E. Cynamon
- Department of Neurological Surgery; Montefiore Medical Center and the Albert Einstein College of Medicine; Bronx New York
| | - Stephanie E. DeLuca
- Department of Neurological Surgery; Montefiore Medical Center and the Albert Einstein College of Medicine; Bronx New York
| | - Eric S. Taub
- Department of Neurological Surgery; Montefiore Medical Center and the Albert Einstein College of Medicine; Bronx New York
| | - Arthur A. Pilla
- Department of Biomedical Engineering; Columbia University; New York New York
- Department of Orthopedics; Mount Sinai School of Medicine; New York New York
| | - Diana Casper
- Department of Neurological Surgery; Montefiore Medical Center and the Albert Einstein College of Medicine; Bronx New York
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Tran MTD, Skovbjerg S, Arendt-Nielsen L, Christensen KB, Elberling J. Transcranial pulsed electromagnetic fields for multiple chemical sensitivity: study protocol for a randomized, double-blind, placebo-controlled trial. Trials 2013; 14:256. [PMID: 23947742 PMCID: PMC3765111 DOI: 10.1186/1745-6215-14-256] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2013] [Accepted: 08/05/2013] [Indexed: 12/17/2022] Open
Abstract
Background Multiple chemical sensitivity (MCS) is a chronic condition of unknown etiology. MCS is characterized by recurrent nonspecific symptoms from multiple organ systems in response to chemical exposures in concentrations that are normally tolerated by the majority of the population. The symptoms may have severe impact on patients’ lives, but an evidence-based treatment for the condition is nonexisting. The pathophysiology is unclarified, but several indicators point towards abnormal processing of sensory signals in the central nervous system. Pulsed electromagnetic fields (PEMF) offer a promising new treatment for refractory depression and can be targeted at the brain, thereby activating biochemical cell processes. Methods/Design In a parallel, randomized, double-blind, placebo-controlled trial conducted at the Danish Research Centre for Chemical Sensitivities, the effects of PEMF in MCS patients will be assessed using the Re5 Independent System. Based on sample size estimation, 40 participants will be randomized to either PEMF therapy or placebo. The allocation sequence will be generated by computer. All involved parties (that is, participants, investigators, the research nurse, and the statistician) will be blinded to group allocation. The participants will receive PEMF therapy or placebo applied transcranially 30 minutes twice a day for 7 days a week over 6 consecutive weeks. Outcomes will be measured at baseline, once weekly during treatment, post treatment, and at 2.5-month and 4.5-month follow-up according to a predefined timetable. The primary outcome will be a measurement of the impact of MCS on everyday life. The secondary outcomes will be measurements of MCS symptoms, psychological distress (stress, anxiety or depressive symptoms), capsaicin-induced secondary punctate hyperalgesia, immunological markers in serum, and quality of life. Discussion This trial will assess the effects of PEMF therapy for MCS. Currently, there is no treatment with a documented effect on MCS, and in terms of healthcare there is very little to offer these patients. There is thus a great need for well-conducted randomized trials aimed at assessing possible treatment effects. A positive outcome will pave the way for improved healthcare and understanding of this very disabling and overlooked condition. Trial registration ClinicalTrials.gov, NCT01834781
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Affiliation(s)
- Marie Thi Dao Tran
- The Danish Research Centre for Chemical Sensitivities, Department of Dermato-Allergology, Copenhagen University Hospital Gentofte, Ledreborg Allé 40, 2, th,, DK-2820 Gentofte, Denmark.
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Mert T, Ocal I, Guzel AI, Gunay I. Clodronate changes neurobiological effects of pulsed magnetic field on diabetic rats with peripheral neuropathy. Electromagn Biol Med 2013; 32:342-54. [DOI: 10.3109/15368378.2012.721846] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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Wahls TL, Reese D, Kaplan D, Darling WG. Rehabilitation with Neuromuscular Electrical Stimulation Leads to Functional Gains in Ambulation in Patients with Secondary Progressive and Primary Progressive Multiple Sclerosis: A Case Series Report. J Altern Complement Med 2010; 16:1343-9. [DOI: 10.1089/acm.2010.0080] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- Terry L. Wahls
- Veterans Administration (VA), Iowa City VA Medical Center (VAMC), Iowa City, IA
- Center for Research in the Implementation of Innovative Strategies in Practice (CRIISP) VA HSR&D Center of Excellence, VA Iowa City VAMC, Iowa City, IA
- Division of General Medicine, Department of Internal Medicine, University of Iowa Carver College of Medicine, Iowa City, IA
| | | | - Daniel Kaplan
- University of Iowa Carver College of Medicine, Iowa City, IA
| | - Warren G. Darling
- Department of Health and Human Physiology, University of Iowa College of Liberal Arts and Sciences, Iowa City, IA
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22
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Gunay I, Mert T. Pulsed magnetic fields enhance the rate of recovery of damaged nerve excitability. Bioelectromagnetics 2010; 32:200-8. [DOI: 10.1002/bem.20629] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2010] [Accepted: 10/06/2010] [Indexed: 11/09/2022]
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Wang W, Itoh S, Yamamoto N, Okawa A, Nagai A, Yamashita K. Enhancement of nerve regeneration along a chitosan nanofiber mesh tube on which electrically polarized beta-tricalcium phosphate particles are immobilized. Acta Biomater 2010; 6:4027-33. [PMID: 20451674 DOI: 10.1016/j.actbio.2010.04.027] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2010] [Revised: 04/28/2010] [Accepted: 04/30/2010] [Indexed: 11/25/2022]
Abstract
The ability of beta-tricalcium phosphate (beta-TCP) particles to store electric charge was confirmed by thermally stimulated depolarization current measurement as well as surface potential measurement. The efficacy of stored electrical charge on beta-TCP particles in enhancing nerve regeneration was evaluated. Bridge grafting was performed into sciatic nerve defects in Wistar rats with the following tubes: chitosan mesh tubes; chitosan mesh tubes on which beta-TCP particles with or without electrical polarization treatment had been immobilized (polarized and non-polarized tubes, respectively). As a control, isografts were used. Both motor and sensory nerve function as well as electrophysiological recovery progressed with time in each group. Immunofluorescence revealed rapider nerve regeneration in the polarized tube group compared with the non-polarized tube group. The axon density and axon area in the polarized tube group were significantly greater than those in the chitosan mesh tube and non-polarized group, and showed no significant differences from the control group. These results suggest that the stored charge on electrically polarized beta-TCP particles immobilized on chitosan mesh tubes may enhance nerve regeneration to the same extent as isografting.
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Moreno-López B. Local isoform-specific NOS inhibition: a promising approach to promote motor function recovery after nerve injury. J Neurosci Res 2010; 88:1846-57. [PMID: 20143424 DOI: 10.1002/jnr.22353] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Physical injury to a nerve is the most frequent cause of acquired peripheral neuropathy, which is responsible for loss of motor, sensory and/or autonomic functions. Injured axons in the peripheral nervous system maintain the capacity to regenerate in adult mammals. However, after nerve transection, stumps of damaged nerves must be surgically joined to guide regenerating axons into the distal nerve stump. Even so, severe functional limitations persist after restorative surgery. Therefore, the identification of molecules that regulate degenerative and regenerative processes is indispensable in developing therapeutic tools to accelerate and improve functional recovery. Here, I consider the role of nitric oxide (NO) synthesized by the three major isoforms of NO synthases (NOS) in motor neuropathy. Neuronal NOS (nNOS) seems to be the primary source of NO that is detrimental to the survival of injured motoneurons. Endothelial NOS (eNOS) appears to be the major source of NO that interferes with axonal regrowth, at least soon after injury. Finally, NO derived from inducible NOS (iNOS) or nNOS is critical to the process of lipid breakdown for Wallerian degeneration and thereby benefits axonal regrowth. Specific inhibitors of these isoforms can be used to protect injured neurons from degeneration and promote axonal regeneration. A cautious proposal for the treatment of acquired motor neuropathy using therapeutic tools that locally interfere with eNOS/nNOS activities seems to merit consideration.
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Axonal release of glutamate analog, d-2,3-3H-Aspartic acid and l-14C-proline from segments of sciatic nerve following electrical and magnetic stimulation. Neurosci Lett 2009; 458:19-22. [DOI: 10.1016/j.neulet.2009.04.024] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2009] [Revised: 03/31/2009] [Accepted: 04/10/2009] [Indexed: 11/21/2022]
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Pulsed Electromagnetic Fields to Reduce Diabetic Neuropathic Pain and Stimulate Neuronal Repair: A Randomized Controlled Trial. Arch Phys Med Rehabil 2009; 90:1102-9. [DOI: 10.1016/j.apmr.2009.01.019] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2008] [Revised: 12/16/2008] [Accepted: 01/11/2009] [Indexed: 01/13/2023]
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Santini MT, Rainaldi G, Indovina PL. Cellular effects of extremely low frequency (ELF) electromagnetic fields. Int J Radiat Biol 2009; 85:294-313. [PMID: 19399675 DOI: 10.1080/09553000902781097] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
PURPOSE The major areas of research that have characterised investigation of the impact of extremely low frequency (ELF) electromagnetic fields on living systems in the past 50 years are discussed. In particular, selected studies examining the role of these fields in cancer, their effects on immune and nerve cells, and the positive influence of these ELF fields on bone and nerve cells, wound healing and ischemia/reperfusion injury are explored. CONCLUSIONS The literature indicates that there is still no general agreement on the exact biological detrimental effects of ELF fields, on the physical mechanisms that may be behind these effects or on the extent to which these effects may be harmful to humans. Nonetheless, the majority of the in vitro experimental results indicate that ELF fields induce numerous types of changes in cells. Whether or not the perturbations observed at the cellular level can be directly extrapolated to negative effects in humans is still unknown. However, the myriad of effects that ELF fields have on biological systems should not be ignored when evaluating risk to humans from these fields and, consequently, in passing appropriate legislation to safeguard both the general public and professionally-exposed workers. With regard to the positive effects of these fields, the possibility of testing further their efficacy in therapeutic protocols should also not be overlooked.
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Affiliation(s)
- Maria T Santini
- Dipartimento di Ematologia, Oncologia e Medicina Molecolare, Istituto Superiore di Sanita, Viale Regina Elena, Rome.
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Meyer JF, Wolf B, Gross GW. Magnetic stimulation and depression of mammalian networks in primary neuronal cell cultures. IEEE Trans Biomed Eng 2009; 56:1512-23. [PMID: 19203881 DOI: 10.1109/tbme.2009.2013961] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
For transcranial magnetic stimulation (TMS), the coupling of induced electric fields with neurons in gray matter is not well understood. There is little information on optimal stimulation parameters and on basic cellular mechanisms. For this reason, magnetic stimulation of spontaneously active neuronal networks, grown on microelectrode arrays in culture, was employed as a test environment. This allowed use of smaller coils and the continual monitoring of network action potential (AP) activity before, during, and for long periods after stimulation. Biphasic, rectangular, and 500 micros long pulses were used at mean pulse frequencies (MPFs) ranging from 3 to 100 Hz on both spinal cord (SC) and frontal cortex (FC) cultures. Contrary to stimulation of organized fiber bundles, APs were not elicited directly. Responses were predominantly inhibitory, dose dependent, with onset times between 10 s and several minutes. Spinal networks showed a greater sensitivity to activity suppression. Under pharmacological disinhibition, some excitation was seen at low pulse frequencies. FC cultures showed greater excitatory responses than SC networks. The observed primary inhibitory responses imply interference with synaptic exocytosis mechanisms. With 20,000 pulses at 10 Hz, 40% inhibition was maintained for over 30 min with full recovery, suggesting possible application to nonchemical, noninvasive pain management.
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Affiliation(s)
- Jochen F Meyer
- Department of Medical Electronics, Technical University of Munich, Munich 80333, Germany.
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Sunico CR, Portillo F, González-Forero D, Kasparov S, Moreno-López B. Evidence for a detrimental role of nitric oxide synthesized by endothelial nitric oxide synthase after peripheral nerve injury. Neuroscience 2008; 157:40-51. [PMID: 18824216 DOI: 10.1016/j.neuroscience.2008.09.001] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2008] [Revised: 09/02/2008] [Accepted: 09/03/2008] [Indexed: 12/17/2022]
Abstract
Physical injury to a nerve is the most common cause of acquired peripheral neuropathy. Identification of molecules involved in degenerative and regenerative processes is a key step toward development of therapeutic tools in order to accelerate motor, sensory and/or autonomic function recovery. We have studied the role of nitric oxide (NO) using as a model the severe crushing of a motor nerve in adult rats. This type of injury up-regulates the three isoforms of nitric oxide synthase (NOS) in the affected nerve. Chronic systemic inhibition of NOS accelerated the onset of functional muscle reinnervation evaluated by the recording of compound muscle action potential evoked by electrical stimulation of the injured nerve. Besides, it increased the number of back-labeled motoneurons by application, 2 days after injury, of a retrograde marker 10 mm distal to the crushing site. These effects were mimicked by chronic specific inhibition of the endothelial isoform of nitric oxide synthase (eNOS), but not by specific inhibitors of the neuronal or inducible isoform. Next, we intraneurally injected a replication-deficient adenoviral vector directing the expression of a dominant negative mutant of eNOS (Ad-TeNOS). A single injection of Ad-TeNOS on the day of crushing significantly accelerated functional recovery of neuromuscular junction and increased axonal regeneration. Moreover, Ad-TeNOS did not compromise motoneuron viability or stability of reestablished neuromuscular junctions. Taken together, these results suggest that NO of endothelial origin slows down muscle reinnervation by means of detrimental actions on axonal regeneration after peripheral nerve injury. These experiments identify eNOS as a potential therapeutic target for treatment of traumatic nerve injuries and highlight the potential of gene therapy in treating injuries of this type using viral vectors to suppress the activity of eNOS.
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Affiliation(s)
- C R Sunico
- Area de Fisiología, Facultad de Medicina, Universidad de Cádiz, Plaza Falla, 9, 11003 Cádiz, Spain
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Ahmed Z, Wieraszko A. The mechanism of magnetic field-induced increase of excitability in hippocampal neurons. Brain Res 2008; 1221:30-40. [DOI: 10.1016/j.brainres.2008.05.007] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2008] [Revised: 04/30/2008] [Accepted: 05/05/2008] [Indexed: 11/29/2022]
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Johansson A, Forsgren S, Stenberg B, Wilén J, Kalezic N, Sandström M. No effect of mobile phone-like RF exposure on patients with atopic dermatitis. Bioelectromagnetics 2008; 29:353-62. [DOI: 10.1002/bem.20402] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Walker JL, Kryscio R, Smith J, Pilla A, Sisken BF. Electromagnetic Field Treatment of Nerve Crush Injury in a Rat Model: Effect of Signal Configuration on Functional Recovery. Bioelectromagnetics 2007; 28:256-63. [PMID: 17265446 DOI: 10.1002/bem.20302] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Electromagnetic fields (EMFs) have been demonstrated to enhance mammalian peripheral nerve regeneration in vitro and in vivo. Using an EMF signal shown to enhance neurite outgrowth in vitro, we tested this field in vivo using three different amplitudes. The rat sciatic nerve was crushed. Whole body exposure was performed for 4 h/day for 5 days in a 96-turn solenoid coil controlled by a signal generator and power amplifier. The induced electric field at the target tissue consisted of a bipolar rectangular pulse, having 1 and 0.3 ms durations in each polarity, respectively. Pulse repetition rate was 2 per second. By varying the current, the coils produced fields consisting of sham (no current) and peak magnetic fields of 0.03 mT, 0.3 mT, and 3 mT, corresponding to peak induced electric fields of 1, 10, and 100 microV/cm, respectively, at the tissue target. Walking function was assessed over 43 days using video recording and measurement of the 1-5 toe-spread, using an imaging program. Comparing injured to uninjured hind limbs, mean responses were evaluated using a linear mixed statistical model. There was no difference found in recovery of the toe-spread function between any EMF treatments compared to sham.
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Affiliation(s)
- Janet L Walker
- Department of Orthopaedic Surgery, University of Kentucky, Lexington, Kentucky, USA.
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Abstract
First reduced to science by Maxwell in 1865, electromagnetic technology as therapy received little interest from basic scientists or clinicians until the 1980s. It now promises applications that include mitigation of inflammation (electrochemistry) and stimulation of classes of genes following onset of illness and injury (electrogenomics). The use of electromagnetism to stop inflammation and restore tissue seems a logical phenomenology, that is, stop the inflammation, then upregulate classes of restorative gene loci to initiate healing. Studies in the fields of MRI and NMR have aided the understanding of cell response to low energy EMF inputs via electromagnetically responsive elements. Understanding protein iterations, that is, how they process information to direct energy, we can maximize technology to aid restorative intervention, a promising step forward over current paradigms of therapy.
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Affiliation(s)
- Glen A Gordon
- Electromagnetic Research and Education Foundation (EMREF), Port Gamble, WA, USA.
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Massa SM, Xie Y, Yang T, Harrington AW, Kim ML, Yoon SO, Kraemer R, Moore LA, Hempstead BL, Longo FM. Small, nonpeptide p75NTR ligands induce survival signaling and inhibit proNGF-induced death. J Neurosci 2006; 26:5288-300. [PMID: 16707781 PMCID: PMC6675309 DOI: 10.1523/jneurosci.3547-05.2006] [Citation(s) in RCA: 120] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Studies showing that neurotrophin binding to p75NTR can promote cell survival in the absence of Trk (tropomyosin-related kinase) receptors, together with recent structural data indicating that NGF may bind to p75NTR in a monovalent manner, raise the possibility that small molecule p75NTR ligands that positively regulate survival might be found. A pharmacophore designed to capture selected structural and physical chemical features of a neurotrophin domain known to interact with p75NTR was applied to in silico screening of small molecule libraries. Small, nonpeptide, monomeric compounds were identified that interact with p75NTR. In cells showing trophic responses to neurotrophins, the compounds promoted survival signaling through p75NTR-dependent mechanisms. In cells susceptible to proneurotrophin-induced death, compounds did not induce apoptosis but inhibited proneurotrophin-mediated death. These studies identify a unique range of p75NTR behaviors that can result from isolated receptor liganding and establish several novel therapeutic leads.
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Affiliation(s)
- Stephen M. Massa
- Correspondence should be addressed to either of the following: Dr. Frank M. Longo, Department of Neurology and Neurological Sciences A343, Stanford University, 300 Pasteur Drive, Stanford, CA 94305, or Dr. Stephen M. Massa, Department of Neurology (127), San Francisco Veterans Affairs Medical Center, 4150 Clement Street, San Francisco, CA 94121,
| | - Youmei Xie
- Correspondence should be addressed to either of the following: Dr. Frank M. Longo, Department of Neurology and Neurological Sciences A343, Stanford University, 300 Pasteur Drive, Stanford, CA 94305, or Dr. Stephen M. Massa, Department of Neurology (127), San Francisco Veterans Affairs Medical Center, 4150 Clement Street, San Francisco, CA 94121,
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Zhang Y, Ding J, Duan W, Fan W. Influence of pulsed electromagnetic field with different pulse duty cycles on neurite outgrowth in PC12 rat pheochromocytoma cells. Bioelectromagnetics 2005; 26:406-11. [PMID: 15887254 DOI: 10.1002/bem.20116] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The influence of low frequency (50 Hz repetition rate) pulsed electromagnetic field (EMF) on PC12 cell neurite outgrowth in vitro was investigated in this study. We studied the percentage of neurite bearing cells, average length of neurites, and directivity of neurite outgrowth in PC12 cells cultured for 96 h in the presence of nerve growth factor (NGF). PC12 cells were exposed in one incubator to pulsed EMF at 1.36 mT (peak value) generated by a pair of Helmholtz coils, and the control samples were placed in another identical incubator. We found that the pulse duty cycle had significant effect on neurite outgrowth. Low (10%) pulse on-time significantly inhibited the percentage of neurite bearing cells, but at the same time increased the average length of neurites, while 100% on-time (DC) had exactly the opposite effects. Furthermore, we found that neurites were prone to extend along the direction of pulsed EMF with 10% pulse on-time. Our studies show that neurite outgrowth in PC12 cells is sensitive to the pulse duty and this sensitivity was associated with NGF concentration.
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Affiliation(s)
- Y Zhang
- Department of Materials Science, National University of Singapore, Singapore
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Crowe MJ, Sun ZP, Battocletti JH, Macias MY, Pintar FA, Maiman DJ. Exposure to pulsed magnetic fields enhances motor recovery in cats after spinal cord injury. Spine (Phila Pa 1976) 2003; 28:2660-6. [PMID: 14673366 DOI: 10.1097/01.brs.0000099385.46102.0d] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
STUDY DESIGN Animal model study of eight healthy commercial cats was conducted. OBJECTIVE To determine whether pulsed electromagnetic field (PMF) stimulation results in improvement of function after contusive spinal cord injury in cats. SUMMARY OF BACKGROUND DATA PMF stimulation has been shown to enhance nerve growth, regeneration, and functional recovery of peripheral nerves. Little research has been performed examining the effects of PMF stimulation on the central nervous system and no studies of PMF effects on in vivo spinal cord injury (SCI) models have been reported. MATERIALS AND METHODS PMF stimulation was noninvasively applied for up to 12 weeks to the midthoracic spine of cats with acute contusive spinal cord injury. The injury was produced using a weight-drop apparatus. Motor functions were evaluated with the modified Tarlov assessment scale. Morphologic analyses of the injury sites and somatosensory-evoked potential measurements were conducted to compare results between PMF-stimulated and control groups. RESULTS There was a significant difference in locomotor recovery between the PMF-stimulated and control groups. Although not statistically significant, PMF-stimulated spinal cords demonstrated greater sparing of peripheral white matter and smaller lesion volumes compared to controls. Somatosensory-evoked potential measurements indicated that the PMF-stimulated group had better recovery of preinjury waveforms than the control group; however, this observation also was not statistically significant because of the small sample size. CONCLUSIONS This preliminary study indicates that pulsed magnetic fields may have beneficial effects on motor function recovery and lesion volume size after acute spinal cord injury.
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Affiliation(s)
- Maria J Crowe
- Neuroscience Research Laboratories, The Clement J. Zablocki VA Medical Center, Milwaukee, WI 53295, USA.
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Shah JP, Midkiff P, Brandt PC, Sisken BF. Growth and differentiation of PC6 cells: the effects of pulsed electromagnetic fields (PEMF). Bioelectromagnetics 2001; 22:267-71. [PMID: 11298388 DOI: 10.1002/bem.49] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Previous studies in our laboratory showed that neurite outgrowth in vitro and nerve regeneration in vivo were stimulated by 2 Hz, 0.3 mT (3 G) pulsed electromagnetic fields (PEMF). To learn more about the effects of PEMF on nerve cells, we exposed PC6 cells, a standard neuronal-like cell model, to the same pulsed electromagnetic fields for 2 h/day for 2 days and asked whether two different cell processes, proliferation and differentiation, were affected. The cells were also treated with a differentiating agent, nerve growth factor (NGF), to further define any interactive effects. We found that proliferation was unaffected by either PEMF or NGF alone or in combination. Differentiation, expressed as neurite outgrowth, was strongly upregulated with NGF, but this NGF response was significantly depressed in cells treated with PEMF.
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Affiliation(s)
- J P Shah
- Center for Biomedical Engineering and Department of Anatomy and Neurobiology, University of Kentucky, Lexington 40506-0070, USA
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Lundborg G. A 25-year perspective of peripheral nerve surgery: evolving neuroscientific concepts and clinical significance. J Hand Surg Am 2000; 25:391-414. [PMID: 10811744 DOI: 10.1053/jhsu.2000.4165] [Citation(s) in RCA: 428] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
In spite of an enormous amount of new experimental laboratory data based on evolving neuroscientific concepts during the last 25 years peripheral nerve injuries still belong to the most challenging and difficult surgical reconstructive problems. Our understanding of biological mechanisms regulating posttraumatic nerve regeneration has increased substantially with respect to the role of neurotrophic and neurite-outgrowth promoting substances, but new molecular biological knowledge has so far gained very limited clinical applications. Techniques for clinical approximation of severed nerve ends have reached an optimal technical refinement and new concepts are needed to further increase the results from nerve repair. For bridging gaps in nerve continuity little has changed during the last 25 years. However, evolving principles for immunosuppression may open new perspectives regarding the use of nerve allografts, and various types of tissue engineering combined by bioartificial conduits may also be important. Posttraumatic functional reorganizations occurring in brain cortex are key phenomena explaining much of the inferior functional outcome following nerve repair, and increased knowledge regarding factors involved in brain plasticity may help to further improve the results. Implantation of microchips in the nervous system may provide a new interface between biology and technology and developing gene technology may introduce new possibilities in the manipulation of nerve degeneration and regeneration.
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Affiliation(s)
- G Lundborg
- Department of Hand Surgery, Malmö University Hospital, Sweden
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