Moderate Intensity Static Magnetic Fields Prevent Thrombus Formation in Rats and Mice

Research progress on the effects and mechanisms of magnetic field on neurodegenerative diseases

With the progress of modern science and technology, magnetic therapy technology develops rapidly, and many types of magnetic therapy methods continue to emerge, making magnetic therapy one of the main techniques of physiotherapy. With the continuous development of magnetic field research and clinical applications, magnetic therapy, as a non-invasive brain stimulation therapy technology, has attracted much attention due to its potential in the treatment of motor dysfunction, cognitive impairment and speech disorders in patients with neurodegenerative diseases. However, the role of magnetic fields in the prognosis and treatment of neurodegenerative diseases and their mechanisms remain largely unexplored. In this paper, the therapeutic effect and neuroprotective mechanism of the magnetic field on neurodegenerative diseases are reviewed, and the new magnetic therapy techniques are also summarized. Although the neuroprotective mechanism of magnetic field cannot be fully elaborated, it is helpful to promote the application of magnetic field in neurodegenerative diseases and provide a new theoretical basis for the related magnetic field research in the later period.

Transcranial Magneto-Acoustic Stimulation Protects Synaptic Rehabilitation from Amyloid-Beta Plaques via Regulation of Microglial Functions

Transcranial magneto-acoustic stimulation (TMAS), which is characterized by high spatiotemporal resolution and high penetrability, is a non-invasive neuromodulation technology based on the magnetic-acoustic coupling effect. To reveal the effects of TMAS treatment on amyloid-beta (Aβ) plaque and synaptic plasticity in Alzheimer's disease, we conducted a comparative analysis of TMAS and transcranial ultrasound stimulation (TUS) based on acoustic effects in 5xFAD mice and BV2 microglia cells. We found that the TMAS-TUS treatment effectively reduced amyloid plaque loads and plaque-associated neurotoxicity. Additionally, TMAS-TUS treatment ameliorated impairments in long-term memory formation and long-term potentiation. Moreover, TMAS-TUS treatment stimulated microglial proliferation and migration while enhancing the phagocytosis and clearance of Aβ. In 5xFAD mice with induced microglial exhaustion, TMAS-TUS treatment-mediated Aβ plaque reduction, synaptic rehabilitation improvement, and the increase in phospho-AKT levels were diminished. Overall, our study highlights that stimulation of hippocampal microglia by TMAS treatment can induce anti-cognitive impairment effects via PI3K-AKT signaling, providing hope for the development of new strategies for an adjuvant therapy for Alzheimer's disease.

Electromagnetic field and cardiovascular diseases: A state-of-the-art review of diagnostic, therapeutic, and predictive values

Despite encouraging advances in early diagnosis and treatment, cardiovascular diseases (CVDs) remained a leading cause of morbidity and mortality worldwide. Increasing evidence has shown that the electromagnetic field (EMF) influences many biological processes, which has attracted much attention for its potential therapeutic and diagnostic modalities in multiple diseases, such as musculoskeletal disorders and neurodegenerative diseases. Nonionizing EMF has been studied as a therapeutic or diagnostic tool in CVDs. In this review, we summarize the current literature ranging from in vitro to clinical studies focusing on the therapeutic potential (external EMF) and diagnostic potential (internal EMF generated from the heart) of EMF in CVDs. First, we provided an overview of the therapeutic potential of EMF and associated mechanisms in the context of CVDs, including cardiac arrhythmia, myocardial ischemia, atherosclerosis, and hypertension. Furthermore, we investigated the diagnostic and predictive value of magnetocardiography in CVDs. Finally, we discussed the critical steps necessary to translate this promising approach into clinical practice.

Inhibitory Effect of Lactobacillus delbrueckii subsp. bulgaricus KSFY07 on Kappa-Carrageenan-Induced Thrombosis in Mice and the Regulation of Oxidative Damage

A mouse thrombosis model was established by kappa-carrageenan to observe the inhibitory effect of Lactobacillus delbrueckii subsp. bulgaricus KSFY07 (LDSB-KSFY07) on thrombosis and the oxidative stress response. Mouse serum, liver tissue-related indicators, and intestinal microbial composition were measured by examining the expression of microbes in mouse faeces using a biochemical kit, slice observations, and quantitative polymerase chain reaction (qPCR) experiments. The results showed that LDSB-KSFY07 effectively reduced the degree of black tail in thrombotic mice, increased activated partial thromboplastin time (APTT), and decreased thrombin time (TT), fibrinogen (FIB), and prothrombin time (PT) in thrombotic mice. LDSB-KSFY07 was also able to reduce malondialdehyde (MDA) levels and increase superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) levels in the serum and liver tissues of thrombotic mice. Pathological observations showed that LDSB-KSFY07 reduced liver tissue lesions and tail vein thrombosis. Further, experimental results showed that LDSB-KSFY07 was able to upregulate the mRNA expression of copper/zinc-SOD (Cu/Zn-SOD), manganese-SOD, and GSH-Px in the liver tissue of thrombotic mice. Moreover, LDSB-KSFY07 was also able to downregulate the mRNA expression of NF-κB p65, intercellular cell adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), and E-selectin in tail vein vascular tissue. Meanwhile, LDSB-KSFY07 could raise plasminogen activator inhibitor-1 (PAI-1) mRNA expression and reduce tissue plasminogen activator (t-PA) expression in heart and tail vein vascular tissues of thrombotic mice. A mouse faeces examination revealed that LDSB-KSFY07 could also upregulate Bacteroides, Lactobacterium, and Bifidobacterium microbial expression and downregulate Firmicutes expression in the gut. These results indicate that LDSB-KSFY07 was able to inhibit mouse thrombosis and reduce liver oxidative stress damage in thrombus mice and show that high concentrations of LDSB-KSFY07 provided a better response similar to that of the drug heparin.

Moderate intensity of static magnetic fields can alter the avoidance behavior and fat storage of Caenorhabditis elegans via serotonin

Man-made static magnetic fields (SMFs) widely exist in human life as a physical environmental factor. However, the biological responses to moderate SMFs exposure and their underlying mechanisms are largely unknown. The present study was focused on exploring the nervous responses to moderate-intensity SMFs at 0.5 T and 1 T in Caenorhabditis elegans (C. elegans). We found that SMFs at either 0.5 T or 1 T had no statistically significant effects on the locomotor behaviors, while the 1 T magnetic field increased pharyngeal pumping. The avoidance behavior of the pathogenic Pseudomonas aeruginosa was greatly decreased in either 0.5 T or 1 T SMFs exposed nematodes, and the learning index was reducede from 0.52 ± 0.11 to 0.23 ± 0.17 and 0.16 ± 0.11, respectively. The total serotonin level was increased by 17.08% and 16.45% with the treatment of 0.5 T and 1 T SMF, compared to the control group; however, there were minimal effects of SMFs on other three neurotransmitters including choline, γ-aminobutyric acid (GABA), dopamine. RT-qPCR was used to further investigate the expression of serotonin-related genes, including rate-limiting enzymes, transcription factors and transport receptors. The expression levels of tph-1 and unc-86 genes were increased by SMF exposure, while those of ocr-2, osm-9, ser-1 and mod-1 genes were decreased. With the staining of lipid in either wild-type N2 or tph-1 mutants, we found that 0.5 T and 1 T SMFs decreased fat storage in C. elegans via serotonin pathway. Our study demonstrated that moderate-intensity SMFs induced neurobehavioral disorder and the reduction of fat storage by disturbing the secretion of serotonin in C. elegans, which provided new insights into elucidating nervous responses of C. elegans to moderate-intensity SMFs.

Lactobacillus plantarum HFY05 Attenuates Carrageenan-Induced Thrombosis in Mice by Regulating NF-κB Pathway-Associated Inflammatory Responses

In this study, a carrageenan-induced thrombus model was established in mice to observe the ability of Lactobacillus plantarum KFY05 (LP-KFY05) to inhibit thrombosis through an NF-κB-associated pathway. Biochemical analysis, microscopical observations, quantitative polymerase chain reactions (qPCR) and western blot analysis were used to examine relevant serum and tissue indexes, and the composition of intestinal microorganisms was determined by examining the abundance of microorganisms in feces. The results showed that LP-KFY05 could markedly reduce the degree of black tail in thrombotic mice; increase the activated partial thromboplastin time (APTT); and decrease the thrombin time (TT), fibrinogen (FIB) level, and prothrombin time (PT). LP-KFY05 could also reduce tumor necrosis factor alpha (TNF-α), interleukin-6 (IL-6), and interleukin-1 beta (IL-1β) levels in sera and renal tissues of thrombotic mice. Hematoxylin and eosin staining showed that LP-KFY05 could alleviate renal tissue lesions and tail vein thrombosis. qPCR results showed that LP-KFY05 could down-regulate nuclear factor kappa-B (NF-κB) p65, IL-6, TNF-α, and interferon γ (IFN-γ) mRNA expression in renal tissues, as well as NF-κB p65, intercellular cell adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), and E-selectin mRNA expression in tail vein vascular tissues of thrombotic mice. Western blot analysis showed that LP-KFY05 also down-regulated NF-κB protein expression in renal and tail vein vascular tissues of thrombotic mice. Lastly, LP-KFY05 increased the abundances of Bacteroidetes, Lactobacillus, and Bifidobacterium, as well as decreased the abundance of Firmicutes. These results show that LP-KFY05 can reduce inflammation and inhibit thrombosis in thrombotic mice, and the effects of high concentrations of LP-KFY05 were most pronounced, which were similar to the effects of dipyridamole.

Effects of High Magnetic Fields on the Diffusion of Biologically Active Molecules

The diffusion of biologically active molecules is a ubiquitous process, controlling many mechanisms and the characteristic time scales for pivotal processes in living cells. Here, we show how a high static magnetic field (MF) affects the diffusion of paramagnetic and diamagnetic species including oxygen, hemoglobin, and drugs. We derive and solve the equation describing diffusion of such biologically active molecules in the presence of an MF as well as reveal the underlying mechanism of the MF’s effect on diffusion. We found that a high MF accelerates diffusion of diamagnetic species while slowing the diffusion of paramagnetic molecules in cell cytoplasm. When applied to oxygen and hemoglobin diffusion in red blood cells, our results suggest that an MF may significantly alter the gas exchange in an erythrocyte and cause swelling. Our prediction that the diffusion rate and characteristic time can be controlled by an MF opens new avenues for experimental studies foreseeing numerous biomedical applications.

Study the effect of static magnetic field intensity on drug delivery by magnetic nanoparticles

Employing the magnets in therapy has a long history of treating diseases, and currently new applications such as drug delivery by magnetic nanoparticles are gaining more attention. This research tried to study the effect of static magnetic field intensity on drug delivery by magnetic nanoparticles carrying thrombolytic agents. In this research, Fe₃O₄@SiO₂ nanoparticles carrying streptokinase were applied. The efficiency of thrombolysis and micro-CT-scan images are utilized to study the effect of different magnetic fields (0.1, 0.2, 0.3 and 0.5 T) on thrombolysis. The results confirm that increasing the static magnetic field intensity accelerated the thrombolysis. Increasing the intensity of the magnetic field from 0.1 to 0.3 T leads to an increase in clot dissolution rate from 55 to 89%, respectively. Moreover, micro-CT-scan images revealed that magnetic nanoparticles carrying a thrombolytic agent penetrated deeper into the mesh-like structure of clot as the magnetic field intensities increased, which could lead to further dissolution of the clot.

Finger skin blood perfusion during exposure of ulnar and median nerves to the static magnetic field of a rare-earth magnet: A randomized pilot study

This pilot study's goal was to investigate the impacts of static magnetic fields (SMF) on finger skin blood perfusion (SBP) when exposing the ulnar artery and ulnar and medial nerves to a rare earth concentric magnet for 30 minutes. Control SBP was measured in 4th fingers of adults (n = 12, age 26.0 ± 1.4 years) for 15 minutes using laser-Doppler. Then, active-magnets were placed over one arm's ulnar and median nerves at the wrist and sham-magnets placed at corresponding sites on the other arm. Devices were randomly assigned and placed by an investigator "blinded" to device type. The maximum SMF perpendicular to skin was 0.28 T measured 2 mm from magnet surface. The tangential field at this distance was 0.20 T. SBP was analyzed and tested for differential effects attributable to magnets compared to shams in each of the 5-minute intervals over the full 45-minute experiment. Results showed no statistically significant difference between SBP measured on the magnet-treated side compared to the sham side. Magnet and sham side SBP values (mean ± SEM, arbitrary units) prior to device placement were 0.568 ± 0.128 vs. 0.644 ± 0.115, p = .859 and during device placement were 0.627 ± 0.135 vs. 0.645 ± 0.117, p = .857. In conclusion, these findings have failed to uncover any significant effects of the static magnetic field on skin blood perfusion in the young healthy adult population evaluated. Its potential for altering SBP in more mature persons or those with underlying conditions affecting blood flow has not been evaluated but represents the next target of research inquiry. ClinicalTrials.gov registration number is NCT04539704.

Protective Effects of Moderate Intensity Static Magnetic Fields on Diabetic Mice

The purpose of this study was to investigate the effects of moderate-intensity static magnetic field (SMF) on diabetic mice. We studied the effects of SMF on blood glucose of normal mice by starch tolerance and glucose tolerance tests. Then, we evaluated the effects of SMF on blood glucose of diabetic mice by establishing alloxan-induced type 1 diabetic mice and high-fat diet + streptozotocin (STZ)-induced type 2 diabetic mice. The results showed that different magnetic field intensities and blank control did not affect the blood glucose of normal mice. After starch and glucose administration, different magnetic fields could improve the glucose tolerance of normal mice, and this was obvious in the 600 mT group. In the experiment of type 1 diabetic mice induced by alloxan, the results showed that different magnetic field intensities could improve the starch tolerance of mice, and that in the 400 mT group was obvious. In the experiment of type 2 diabetic mice induced by a high-fat diet + STZ, the 400 mT group could reduce food intake and water consumption in the later period. The 600 mT group could improve the starch tolerance of mice. The 400 and 600 mT groups could reduce fasting blood glucose. At the same time, total cholesterol and triglyceride decreased in different magnetic field intensities, and the 600 mT group could significantly increase the serum insulin content of mice. In summary, the results of this study suggest that SMF has a protective role in diabetic mice. Bioelectromagnetics. © 2020 Bioelectromagnetics Society.

Moderate SMFs attenuate bone loss in mice by promoting directional osteogenic differentiation of BMSCs

Background

Osteoporosis is a common metabolic bone disease without effective treatment. Bone marrow-derived mesenchymal stem cells (BMSCs) have the potential to differentiate into multiple cell types. Increased adipogenic differentiation or reduced osteogenic differentiation of BMSCs might lead to osteoporosis. Whether static magnetic fields (SMFs) might influence the adipo-osteogenic differentiation balance of BMSCs remains unknown.

Methods

The effects of SMFs on lineage differentiation of BMSCs and development of osteoporosis were determined by various biochemical (RT-PCR and Western blot), morphological (staining and optical microscopy), and micro-CT assays. Bioinformatics analysis was also used to explore the signaling pathways.

Results

In this study, we found that SMFs (0.2–0.6 T) inhibited the adipogenic differentiation of BMSCs but promoted their osteoblastic differentiation in an intensity-dependent manner. Whole genomic RNA-seq and bioinformatics analysis revealed that SMF (0.6 T) decreased the PPARγ-mediated gene expression but increased the RUNX2-mediated gene transcription in BMSCs. Moreover, SMFs markedly alleviated bone mass loss induced by either dexamethasone or all-trans retinoic acid in mice.

Conclusions

Taken together, our results suggested that SMF-based magnetotherapy might serve as an adjunctive therapeutic option for patients with osteoporosis.

Supplementary information

Supplementary information accompanies this paper at 10.1186/s13287-020-02004-y.