Static Magnetic Field Exposure Research Articles

A Static Magnetic Field Exposure in Obese Mice Induced by High Fat Diet: Its Effect on T-Box15 Gene and Uncoupling Protein 1 Expression

A Static Magnetic Field Exposure in Obese Mice Induced by High Fat Diet: Its Effect on T-Box15 Gene and Uncoupling Protein 1 Expression

Physiological Responses Revealed Static Magnetic Fields Potentially Improving the Tolerance of Poplar Seedlings to Salt Stress

Magnetic fields play an important role in regulating plant growth and development, especially in improving plant stress tolerance. However, the physiological mechanism underlying the magnetic effects is still unclear. Here, we examined changes in reactive oxygen species (ROS) levels and ion flux in poplar (Populus × deltoides ‘Lulin-2’) seedling roots under salt stress in a static magnetic field (SMF). SMF treatment significantly increased seedling growth and mitigated the effects of salt stress on root growth. Furthermore, SMF treatment activated ROS and calcium signals in poplar roots. Relative to the SMF treatment group, control plants had significantly higher levels of cytoplasmic free Ca2+ ([Ca2+]cyt) and ROS following exposure to high salt concentrations. Under salt conditions, SMF treatment reduced increases in Na+ concentrations and maintained stable K+ and Ca2+ concentrations and K+/Na+ and Ca2+/Na+ ratios. NMT analysis suggests that SMF treatment may drive cation effluxes in poplar seedling roots. Susceptibility tests of Na+-transport inhibitors indicated that SMF treatment contributed to Na+ repulsion and H+ uptake under salt stress. Moreover, SMF exposure allowed roots to retain the ability to reduce salt-induced K+ and Ca2+ root effluxes, and qRT-PCR results demonstrate that SMF treatment can increase the expression of stress-responsive genes such as PtrRBOHF, PtrNHX1 and PtrHA5 in poplar seedlings. Therefore, we conclude that treating poplar seedlings with SMF can help them establish a stable tolerance to salt stress by regulating ROS, [Ca2+]cyt, and their regulatory networks. This study examined the physiological responses of poplar to SMF exposure under salt stress, providing insights into plant magnetobiological effects.

Effects of static magnetic field on the sulfate metabolic pathway involved in Magnetospirillum magneticum AMB-1 cell growth and magnetosome formation.

Magnetotactic bacteria (MTB) can use their unique intracellular magnetosome organelles to swim along the Earth's magnetic field. They play important roles in the biogeochemical cycles of iron and sulfur. Previous studies have shown that the applied magnetic fields could affect the magnetosome formation and antioxidant defense systems in MTB. However, the molecular mechanisms by which magnetic fields affect MTB cells remain unclear. We aim to better understand the dark at 28°C-29°C for 20 h, as shownthe interactions between magnetic fields and cells, and the mechanism of MTB adaptation to magnetic field at molecular levels. We performed microbiological, transcriptomic, and genetic experiments to analyze the effects of a weak static magnetic field (SMF) exposure on the cell growth and magnetosome formation in the MTB strain Magnetospirillum magneticum AMB-1. The results showed that a 1.5 mT SMF significantly promoted the cell growth but reduced magnetosome formation in AMB-1, compared to the geomagnetic field. Transcriptomic analysis revealed decreased expression of genes primarily involved in the sulfate reduction pathway. Consistently, knockout mutant lacking adenylyl-sulfate kinase CysC did no more react to the SMF and the differences in growth and Cmag disappeared. Together with experimental findings of increased reactive oxidative species in the SMF-treated wild-type strain, we proposed that cysC, as a key gene, can participate in the cell growth and mineralization in AMB-1 by SMF regulation. This study suggests that the magnetic field exposure can trigger a bacterial oxidative stress response involved in AMB-1 growth and magnetosome mineralization by regulating the sulfur metabolism pathway. CysC may serve as a pivotal enzyme in mediating sulfur metabolism to synchronize the impact of SMF on both growth and magnetization of AMB-1.

Electrokinetic properties of healthy and β-thalassemia erythrocyte membranes under in vitro exposure to static magnetic field

Introduction: The current understanding of the biological impacts of a static magnetic field (SMF) is restricted to the direct interactions of the magnetic field with biological membranes. The electrokinetic (zeta) potential is an electrochemical property of erythrocyte surfaces which was negatively charged in physiological media after SMF exposure (0.1‒2.0 T).Methods: The novel data about electrokinetic parameters of the erythrocytes is determined by microelectrophoresis after SMF-exposure in norm and heterozygous β-thalassemia. The methods of light scattering, lipid peroxidation, fluorescence microscopy are used.Results: The electrokinetic potential of erythrocytes in norm is increased after SMF intensities due to enhanced negatively exposed charges on the outer surface of the membrane accompanied by an increase in light scattering where changes in cell morphology are observed. Conversely, a decrease in the zeta potential of β-thalassemia erythrocytes upon SMF-treatment was determined because of the reduction in the surface electrical charge of the membranes, where a significant decrease in light scattering at 1.5 T and 2.0 T was recorded. Exposure to SMF (0.5–2.0 T) was associated with an increase in the malondialdehyde content in erythrocytes. Biophysical studies regarding the influence of SMF on the electrostatic free energy of cells shows an increase in negative values in healthy erythrocytes, which corresponds to the implementation of a spontaneous process. This is also the process in β-thalassemia cells after SMF exposure with lower negative values of free electrostatic energy than erythrocytes in norm.Discussion: The effect of static magnetic field (SMF 0.1–2.0 T) on the electrokinetic and morphological characteristics of erythrocytes in norm and β-thalassemia is determined and correlated with the increase/reduction in surface charge and shrinkage/swelling of the cells, respectively. Lipid peroxidation of healthy and β-thalassemia erythrocytes caused an enhancement of lipid peroxidation because of the higher concentrations of TBARS products in cellular suspension. SMF (0.1‒2.0 T) altered the spontaneous chemical processes with negative values of electrostatic free energy of erythrocytes in norm and β-thalassemia accompanied by a lower FITC-Concanavalin A binding affinity to membrane receptors (SMF 2.0 T). The electrokinetic properties of human erythrocytes in norm and β-thalassemia upon SMF treatment and their interrelationship with the structural-functional state of the membrane were reported. The presented work would have future fundamental applications in biomedicine.

Static magnetic field exposure improved the volatile composition and aroma attribute of fresh-cut flower mushrooms (Lentinus edodes (Berk) sing)

Aroma attribute and aroma compound (AOC) composition of fresh-cut flower mushrooms under different static magnetic field (SMF) intensities (2 mT, 4 mT, 6 mT, and 8 mT) were evaluated via coupling aroma sensory assessment and headspace-gas chromatography-ion mobility spectrometry with principal component analysis and partial least squares-relationship analysis. Results showed that aroma quality was severely loss after dicing treatment. A total of 43 AOCs were identified from flower mushrooms, and 3-octanone was the predominant compound. Application of 2 mT SMF maintained more acceptable raw mushroom-like, earthy/musty, and almond-like/roasted, and cooked cabbage-like aroma attributes of diced samples, related to maximally retaining the contents of the key AOCs (i.e. 3-octanone, 2-methylbutanal, and dimethyl trisulfide). These findings could provide a technical reference and theoretical basis for improving the aroma quality of fresh-cut mushrooms via magnetic fields and explain the mechanism of aroma enhancement.

Effect of static magnetic field therapy on diabetic neuropathy and quality of life: a double-blind, randomized trial

BackgroundDiabetic peripheral neuropathy (DPN) is a common complication of diabetes mellitus (DM) that can cause annoying symptoms. To address this condition, several treatment approaches have been proposed, including static magnetic field (SMF) therapy, which has shown promise in treating neurological conditions. Therefore, this study aimed to investigate the effects of SMF therapy on symptomatic DPN and the quality of life (QoL) in patients with type 2 diabetes.MethodsA double-blind, randomized, placebo-controlled trial was conducted from April to October 2021. Sixty-four DPN patients (20 males, 44 females) were recruited for the study via invitation. The participants were divided into two groups: the magnet group, which used magnetic ankle bracelets (155 mT) for 12 weeks, and the sham group, which used non-magnetic ankle bracelets for the same duration. Neuropathy Symptom Score (NSS), Neuropathic Disability Score (NDS), and Visual Analogue Scale (VAS) were used to assess neuropathy symptoms and pain. In addition, the Neuropathy Specific Quality of Life Questionnaire (Neuro-QoL) tool was used to measure the patients’ quality of life.ResultsBefore treatment, there were no significant differences between the magnet and sham groups in terms of the NSS scores (P = 0.50), NDS scores (P = 0.74), VAS scores (P = 0.17), and Neuro-QoL scores (P = 0.82). However, after 12 weeks of treatment, the SMF exposure group showed a significant reduction in NSS scores (P < 0.001), NDS scores (P < 0.001), VAS scores (P < 0.001), and Neuro-QoL scores (P < 0.001) compared to the baseline. The changes in the sham group, on the other hand, were not significant.ConclusionAccording to obtained data, SMF therapy is recommended as an easy-to-use and drug-free method for reducing DPN symptoms and improving QoL in diabetic type-2 patients.Trial registration Registered at Iranian Registry of Clinical Trials: IRCT20210315050706N1, 2021/03/16.

P-127 Micro-Magnetic Resonance Spectroscopy of individual mammalian embryos: a safe and non-invasive diagnostic tool for embryo screening in assisted reproduction

Abstract Study question Is micro-magnetic resonance (micro-MRS) a safe tool to non-invasively unravel the metabolic fingerprint of single mammalian embryos? Summary answer We successfully tested the safety of micro-MRS in a mouse model. No long or short-term adverse effect was found in vitro and in vivo. What is known already Non-invasive selection of the best embryo to transfer is one of the most significant challenges for ART professionals. The chemical sensitivity, resolving power, and, more importantly, the non-invasive nature of MRS makes it an excellent candidate to investigate the building blocks of complex organisms. Although MRS is a well-established technique for the biochemical profiling of large organisms, handling small samples like embryos and 3D cell cultures and spheroids alongside sensitivity issues has prevented its adoption for clinical and research applications. Our group has overcome these limitations with microchip-based sensors to leverage non-invasive MRS technology down to the embryo scale. Study design, size, duration This safety study was divided into two main phases in order to test all the components needed to operate the micro-MRS analysis. In phase 1 we used &amp;gt; 800 2-cell embryos to test a) radiofrequency exposure, b) device activation, and c) static magnetic field exposure. In phase 2 we confirmed in-vivo that MF exposure was not affecting live animals (n267) over 3 generations of mice by assessing different IVF outcomes, natural mating, live parameters and histopathology. Participants/materials, setting, methods Cryopreserved 2-cell B6D2F1 mouse embryos were purchased cryopreserved from JanvierLabs. In phase1 embryos were thawed and used for testing micro-MRS main components' safety. Mouse embryo assay (MEA) was used to first assess micro-MRS adverse effects in-vitro. In phase 2 embryos were exposed to magnetic field in a 9.4T Magnet for 1h at 37 °C, then surgically transferred to surrogate mothers. Both mothers and progeny were tracked up to F3. Statistical significance was set at p &amp;lt; 0.05. Main results and the role of chance This is the first study ever conducted to assess the safety and efficacy of micro-MRS on pre-implantation mammalian embryos. Our results show, with statistical significance, that micro-MRS is safe for use in mammalians. In particular, we have de-risked the three main aspects/components that could affect the embryos: 1) Materials to which the embryos are exposed when loaded into the device, 2) Radiofrequency energy required to activate the device and perform a measurement, and 3) Magnetic field required to analyze the embryos biochemistry in a non-invasive way. Overall no adverse effect was observed when the primary IVF outcomes were assessed, such as implantation rate and live birth rate. In addition, no visible alteration of the overall appearance of ED14.5 foetuses, F1, F2 and F3 mice was observed when comparing the mice obtained from treated or control embryos. The surrogate mothers did not display any significant alteration or visible health issues after embryo transfer. F1 and F2 mice were able to naturally mate and conceive new progeny suggesting that the reproductive potential of the animals is not affected by the magnetic field exposure. Furthermore, histopathological analysis of 5 representative organs did not reveal adverse effects on both surrogate mothers or F1 pups. Limitations, reasons for caution A vital step towards establishing MRS as a clinical and research tool is the reliable detection of a wide range of signals from cellular components. Our method is ready for R&amp;D studies, while its clinical application requires further safety studies and protocol optimization. Wider implications of the findings A non-invasive quick assay would provide the means to reveal the role of embryonic lipids throughout development. Micro-MRS can further develop into a safe embryo assay for selection before embryo transfer. This would apply to both human and animal ART, whose success rate is relatively low. Trial registration number NA

Effect of static magnetic field exposure on biohydrogen production via dark fermentation of glucose

The effect of a static magnetic field (SMF) on the microbial activity of anaerobic granular sludge was investigated using a SMF field provided by a magnetic platform with intensities between 30 and 90 mT. BioH2 production was assessed in fed batch fermentation tests from glucose using anaerobic granular sludge with (HT) and without (WHT) heat shock pretreatment (100 ºC, 1 h). Under the conditions tested, 70 mT SMF was the best condition for bioH2 production, with a threefold decrease of lag time, a 12–50% increase in bioH2 production rate, and an improved consumption of iron and phosphate, compared to the controls (no SMF). Exposure to the SMF induced modifications in volatile fatty acid (VFA) production, pH and conductivity, biomass concentration, exopolysaccharide (EPS) composition as well as size and settleability of the granular anaerobic sludge. Microbial analysis showed that in the presence of the SMF, the relative abundance (RA) of Clostridium and Lactobacillus increased in both HT and WHT sludges, while it decreased the RA of Methanosaeta and Methanobacterium. The RA of Terrisporobacter increased with the heat shock, and also the stimulation along the fed batch cycles improved the RA of Terrisporobacter with and without SMF. The application of the SMF as a pre-treatment of inoculum and during bioH2 production seems to be an interesting and easy scaling up strategy to shorten the start-up of the dark fermentation process and help reducing the microbial diversity of the sludge, favouring more specialized species for bioH2 production.

Effects of moderate static magnetic fields on the lipogenesis and lipolysis in different genders of Caenorhabditis elegans

With the rapid development of magnetic technology, the biological effects of moderate static magnetic fields (SMFs) have attracted increasing research interest due to their potential medical diagnosis and treatment application. The present study explored the effects of moderate SMFs on the lipid metabolism of Caenorhabditis elegans (C. elegans) in different genders including male, female, and hermaphrodite. We found that the fat content was significantly decreased by moderate SMFs in wild-type N2 worms, which was associated with their development stages. The diameters of lipid droplets in N2 worms, him-5 worms, and fog-2 worms were greatly decreased by 19.23%, 15.38%, and 23.07% at young adult stage under 0.5 T SMF, respectively. The mRNA levels of lipolysis related genes atgl-1 and nhr-76 were significantly up-regulated by SMF exposure, while the mRNA levels of the lipogenesis related genes fat-6, fat-7, and sbp-1 were down-regulated by SMF, whereas the concentration of β-oxidase was increased. There was a slight effect of SMF on the mRNA levels of β-oxidation related genes. Moreover, the insulin and serotonin pathway were regulated by SMF, instead of the TOR pathway. In wild-type worms, we found that their lifespan was prolonged by exposure to 0.5 T SMF. Our data suggested that moderate SMFs could significantly modify the lipogenesis and lipolysis process in C. elegans in a gender and development stage-dependent manner, which could provide a novel insight into understanding the function of moderate SMFs in living organisms.

Enhancing anammox nitrogen removal by static magnetic field exposure: Performance, microbial community and symbiotic relationship analysis

Anammox batch reactors were operated with different static magnetic field (SMF) intensities (0 mT, 40 mT, and 100 mT). The impacts of SMF and the influent nitrogen concentration on nitrogen removal were analyzed. Sludge characteristics, microbial community structure, and metabolism pathways were explored. The results show that a high nitrogen load greatly decreased the nitrogen removal efficiency. Still, applying SMF with appropriate intensity enhanced the nitrogen removal performance, especially under high nitrogen loading conditions. Systems with 40 mT SMF at normal nitrogen loading conditions had the highest total nitrogen removal efficiency. In contrast, a higher SMF intensity was conducive to the anammox process with a high nitrogen load. Candidatus Kuenenia was fast enriched under high nitrogen loading conditions in the control systems. However, Candidatus Brocadia was more abundant than Ca. Kuenenia in the systems with SMF application. SMF was the main factor affecting the microbial metabolism, enhancing the metabolic pathways related to bacterial growth and resistance to environmental stress. The metabolic interactions between the anammox bacteria and other bacteria were enhanced by applying SMF to the anammox process, especially for the cross-feeding of cofactors and vitamins in the anammox consortia.

Effects of Static Magnetic Field (SMF) Exposure on Coronary Heart Disease (CHD) Risk Indicators

Dyslipidemia is a condition of abnormalities in blood lipids, such as increased LDL and decreased HDL. Exposure to intracellular static magnetic fields (SMFs) can affect membranes to modulate the number of Ca2+ ions, which can affect cell biological effects. Increasing the number of Ca2+ ions will affect the expression of genes that help reduce LDL levels as an indicator of CHD. This study aims to see whether the influence of SMFs can affect calcium levels, lipid profiles, SREBP-2 protein excretion, and LDLR gene expression, which affects the process of breaking down cholesterol. We used obese C57BL/6J male mice divided into standard and HFD feed groups. The HFD feed group was split into Obes0, Obes2, Obes7, Obes14, and Obes21 groups based on the day of exposure. The exposure was carried out with an intensity of Bmax = 2 mT for 1 h daily. After exposure to SMFs, there were changes in blood cholesterol and LDL levels, which tended to decrease in the Obes2 and Obes7 groups and increase in the Obes14 and Obes21 groups. In addition, the exposed group tended to have an increase in the expression of the LDLR gene, SREBP-2 protein, and calcium ion compared to the control. Although it managed to increase after exposure on days 14 and 21, there was a decrease in the expression of the LDLR gene and SREBP-2 protein; hence, the effect of SMF exposure can reduce the risk of CHD. However, research still needs to be done regarding the effective duration of exposure.

1-2​T static magnetic field combined with Ferumoxytol prevent unloading-induced bone loss by regulating iron metabolism in osteoclastogenesis.

With the deepening of magnetic biomedical effects and electromagnetic technology, some medical instruments based on static magnetic field (SMF) have been used in orthopedic-related diseases treatment. Studies have shown SMF could combat osteoporosis by regulating the differentiation of mesenchymal stem cells (MSCs), osteoblast and osteoclast. With the development of nanotechnology, iron oxide nanoparticles (IONPs) have been reported to regulate the process of bone anabolism. As for SMF combined with IONPs, studies indicated osteogenic differentiation of MSCs were promoted by the combination of SMF and IONPs. However, there are few reports on the effects of SMF combined with IONPs on osteoclast. Herein, the purpose of this study was to investigate the effects of high static magnetic field (HiSMF) combined with IONPs on unloading-induced bone loss in vivo and osteoclastic formation in vitro, and elucidated the potential molecular mechanisms. In vivo, C57BL/6​J male mice were unloaded via tail suspension or housed normally. The hindlimb of mice were fixed and exposed to 1-2​T SMF for 1​h every day, 10​mg/kg of Ferumoxytol or saline were injected by tail vein once a week, last for 4 weeks. Bone microstructure, mechanical properties, and osteoclastogenesis were examined respectively. In vitro, the RAW264.7​cells were used to assess the effects of 1-2​T SMF combined with IONPs in osteoclastogenesis. The iron content was detected by atomic absorption spectrometry and Prussian blue staining. DCFH-DA and MitoSOX™ fluorescence staining were used to assess oxidative stress levels. NF-κB and MAPK signaling pathways were examined by western blot assay. In vivo, the results showed 1-2​T SMF and IONPs prevented the damage to bone microstructure and improved the mechanical properties, diminished the number of osteoclasts in unloaded mice, 1-2​T SMF combined with IONPs was found more effective. The iron content in the liver and spleen was reduced by the combination of 1-2​T SMF and IONPs, enhancing iron levels in the femur. In vitro, osteoclast formation was inhibited by 1-2​T SMF and IONPs treatment, and 1-2​T SMF combined with IONPs had a more pronounced effect. Moreover, iron uptake of IONPs in osteoclast was reduced to 1-2​T SMF exposure. Oxidative stress levels were decreased in osteoclast differentiation under 1-2​T SMF combined with IONPs treatment. Molecularly, the expression of NF-κB and MAPK signaling pathways were inhibited under 1-2​T SMF combined with IONPs in osteoclastogenesis. Synthetically, our research illustrated 1-2​T SMF combined with IONPs prevented unloading-induced bone loss by regulating iron metabolism in osteoclastogenesis.Translational potential of this article: As a non-invasive alternative therapy, some medical instruments based on SMF have been used for orthopedic-related diseases treatment for their portability, cheapness and safety. Ferumoxytol (Feraheme™), the first FDA-approved IONP drug for the treatment of iron deficiency anemia, has been also adapted in translational research for osteoporosis. Based on the above-mentioned two points, we found the synergistic effects of SMF and Ferumoxytol for treatment of experimental osteoporosis. These results show translational potentials for clinical application.

Life on Magnet: Long-Term Exposure of Moderate Static Magnetic Fields on the Lifespan and Healthspan of Mice.

All living organisms on the Earth live and evolve in the presence of the weak geomagnetic field, a quasi-uniform static magnetic field (SMF). In the meantime, although the effects of moderate and high SMFs have been investigated on multiple aspects of a living organism, a long-term SMF exposure of more than 1 year has never been reported. Here, we investigated the influence of a moderate SMF (70-220 mT head-to-toe) long-term continuous exposure (1.7 years) to two different SMF directions on healthy male C57BL/6 mice. We found that not only was the lifespan of the mice prolonged, but their healthspan was also improved. The elevated plus maze test and open field test show that SMFs could significantly improve the exploratory and locomotive activities of the aged mice. The Morris water maze test shows that SMFs could improve their spatial learning ability and spatial memory. Tissue examinations reveal that SMFs have an ameliorative effect on oxidative stress in the brain of aged mice, which was reinforced by the cellular assays, showing that SMFs could protect the PC12 cells from D-gal-induced senescence by increasing superoxide dismutase, catalase, and reducing the malonaldehyde levels. Therefore, our data show that the 1.7-year SMF exposure can improve both the lifespan and healthspan of naturally aged mice due to reduced oxidative stress, which indicates that SMFs have the potential to be used as an adjuvant physical therapy to reduce the ageing-induced health risks to benefit animals, and even humans.

280 mT static magnetic field promotes the growth of postpartum condylar cartilage

ABSTRACT Purpose Functional appliances made of permanent magnets have been used in jaw orthopedic treatment. However, whether the static magnetic field (SMF) generated by permanent magnets promotes the developmental sequence of condylar cartilage and thus promotes the growth of the mandible remains to be studied. The aim of this study was to investigate the effects of 280 mT SMF on postnatal condylar chondrogenesis and endochondral ossification and the roles of FLRT3, FGF2 and BMP2 signaling in this chondrodevelopmental sequences. Methods Forty-eight rats were assigned to two groups (control and SMF). The condyles were collected at the specified time points. The histomorphological changes in the condyle were observed by histological staining. The expression of proteins related to the proliferation and differentiation of the condylar cartilage and the changes in subchondral bone microstructure were analyzed by immunohistochemical staining and micro-CT scanning. FLRT3, FGF2, and BMP2 expression was detected by immunofluorescence staining. Results Under SMF stimulation, the cartilage of young rats grew longitudinally and laterally, and the thickness of the cartilage became thinner as it grew. The SMF promoted the proliferation and differentiation of condylar chondrocytes and endochondral ossification and increased subchondral bone mineral density, and BMP2 signaling was involved. Moreover, under SMF loading, the increased expression of FGF2 and FLRT3 were involved in regulating cartilage morphogenesis and growth. In late development, the decreased expression of FGF2/FLRT3 and the increased expression of BMP2 promoted endochondral ossification. The SMF accelerated this opposite expression trend. Conclusion FGF2/FLRT3 and BMP2 signals are involved in the regulatory effect of SMF exposure on chondrogenesis and endochondral ossification, which provides a theoretical basis for the clinical use of magnetic appliances to promote condylar growth.

The Effect of Long-Term Moderate Static Magnetic Field Exposure on Adult Female Mice.

Because of the high cost and safety of ultra-high magnetic resonance imaging (MRI), its application has certain limitations. Whereas 0.5-3 T MRI has been widely applied in hospitals, static magnetic fields (SMFs) have been shown to improve mice mental health and have anti-tumor potentials. Here, we compared the effects of the upward and downward 150 mT SMF groups with the sham group on C57BL/6J adult female mice. Locomotor and exploratory activity were also measured by behavioral tests, including the open field and elevated plus test. Additionally, physiology, pathology indicators and gut microbiota were examined. We found that 150 mT SMFs long-term exposure enhanced locomotive and exploratory activity of mice, especially the downward 150 mT SMF. Compared with the downward 150 mT SMF group, the movement speed and distance in the center area of the sham group were increased by 65.99% (p &lt; 0.0001) and 68.58% (p = 0.0038), respectively. Moreover, compared to the sham group, downward 150 mT SMF increased the number of entrances to the center area by 67.0% (p = 0.0082) and time in the center area by 77.12% (p = 0.0054). Additionally, we observed that upward 150 mT SMF improved the number of follicles (~2.5 times, p = 0.0325) and uterine glands through increasing the total antioxidant capacity and reducing lipid peroxidation level in mice. Gut microbiome analysis showed that 150 mT SMFs long-term exposure improved the microbiota abundance (Clostridium, Bifidobacterium, Ralstonia and Yaniella) in the genus level, which may affect metabolism, anxiety and behavior in adult female mice. Our results demonstrated that 150 mT SMFs long-term exposure not only had good biosafety, but also improved athletic performance, emotion and the function of ovarian, uterine and gut microbiota abundance in adult female mice, which unraveled the potential of moderate long-term SMF exposure in clinical applications.

The light-independent locomotion response to a static magnetic field in Xenopus tadpoles

Increasing numbers of behavioral observations have shown that many organisms can sense magnetic fields in the environment. However, the underlying mechanisms of magnetosensation remain elusive, and a major problem is the lack of an animal model convenient for detecting magnetic responses, especially in vertebrates. We have previously reported that the physical performance of mice decreased after 1 month of exposure to a hypomagnetic field, which probably includes a light-independent mechanism. In this study, we investigated the effects of a static magnetic field on the locomotion of Xenopus tadpoles (stage 48) using a real-time recording system. Because it is speculated that the photosensing system is related to magnetosensation, we triggered the tadpoles to swim by a 30 s light pulse after a 5 min adaptation in the dark and measured the swimming activities of the tadpoles under static magnetic field exposure in both the dark and bright conditions. Compared to the sham control treatment, the presence of a magnet inhibited the movement of the tadpoles under both bright and dark conditions, as shown by reductions in swimming distance, speed, and counts of path adjustment. Moreover, the directional preference for path adaptation was altered when swimming in the dark. These results suggest that tadpoles in the dark can exert a rapid locomotion response to changes in the environmental magnetic field, providing evidence for an intrinsic, light-independent rapid magnetoresponse pathway in tadpoles. In addition, this rapid vertebrate locomotion assay paradigm will be a practical tool to facilitate further investigation of the mechanisms of biomagnetic effects.

THE EFFECT OF STATIC MAGNETIC FIELD EXPOSURE ON BODY WEIGHT AND ADIPOSE CELLS DENSITY OF OBESE MICE

Obesity is a mojar public health problem in worldwide, especially in Indonesia. Obesity in addition to affecting productivity, is also trigger for other chronic disease such as diabetes and cardiac disease. Body mass index is an assessment tool used to assess degree of individual adiposity to define overweight, obesity, and severe obesity.The determination of obesity is based on the calculation of Body Mass Index (BMI), which devide body weight (kg) by height (cm2). In addition to the method of regulating diet, exercise, and bariatric surgery for weight loss, it was reported that the biophysical therapy tool, that is static magnetic field (SMF) became a modality for weight loss. Based on research reports, it proves that the static magnetic field affects weight loss in the group of obese mice after 30 days of exposure. Therefore, in this study, we carried out static magnetic field exposure to obese mice with a field intensity of 2 mT for 1 hour/day. Mice were exposed gradually to SMF on 2, 7, 14, and 21 days to determine the effectiveness of SMF to obesity in mice in terms of weight loss and cellular adipose cell density. The results showed that the weight of mice decreased significantly on 2nd and 7th days of exposure, the trend showed a decrease in body weight until the 14th day. The density of adipose tissue is increased after exposure to SMF on the 14th and 21st days of exposure. It showed that early exposure to SMF (2 and 7 days) could induce weight loss in mice, while cellularly SMF increased adipose cell density on late exposure (14 and 21 days).

Exposure to static magnetic field facilitates selective attention and neuroplasticity in rats

Static magnetic fields (SMF) have neuroprotective and behavioral effects in rats, however, little is known about the effects of SMF on cognition, motor function and the underlying neurochemical mechanisms. In this study, we focused on the effects of short-term (5–10d) and long-term (13–38d) SMF exposure on selective attention and motor coordination of rats, as well as associated alterations in expression level of neuroplasticity-related structural proteins and cryptochrome (CRY1) protein in the cortex, striatum and ventral midbrain. The results showed that 6d SMF exposure significantly enhanced selective attention without affecting locomotor activity in open field. All SMF exposures non-significantly enhanced motor coordination (Rotarod test). Neurochemical analysis demonstrated that 5d SMF exposure increased the expression of cortical and striatal CRY1 and synapsin-1 (SYN1), striatal total synapsins (SYN), and synaptophysin (SYP), growth associated protein-43 (GAP43) and post-synaptic density protein-95 (PSD95) in the ventral midbrain. Exposure to SMF for 14d increased PSD95 level in the ventral midbrain while longer SMF exposure elevated the levels of PSD95 in the cortex, SYN and SYN1 in all the examined brain areas. The increased expression of cortical and striatal CRY1 and SYN1 correlated with the short-lasting effect of SMF on improving selective attention. Collectively, SMF’s effect on selective attention attenuated following longer exposure to SMF whereas its effects on neuroplasticity-related structural biomarkers were time- and brain area-dependent, with some protein levels increasing with longer time exposure. These findings suggest a potential use of SMF for treatment of neurological diseases in which selective attention or neuroplasticity is impaired.

Static Magnetic Fields Regulate T-Type Calcium Ion Channels and Mediate Mesenchymal Stem Cells Proliferation

The static magnetic fields (SMFs) impact on biological systems, induce a variety of biological responses, and have been applied to the clinical treatment of diseases. However, the underlying mechanisms remain largely unclear. In this report, by using human mesenchymal stem cells (MSCs) as a model, we investigated the biological effect of SMFs at a molecular and cellular level. We showed that SMF exposure promotes MSC proliferation and activates the expression of transcriptional factors such as FOS (Fos Proto-Oncogene, AP-1 Transcription Factor Subunit) and EGR1 (Early Growth Response 1). In addition, the expression of signal-transduction proteins p-ERK1/2 and p-JNK oscillate periodically with SMF exposure time. Furthermore, we found that the inhibition of the T-type calcium ion channels negates the biological effects of SMFs on MSCs. Together, we revealed that the SMFs regulate T-type calcium ion channels and mediate MSC proliferation via the MAPK signaling pathways.

The Biokinetics and Toxicology of Fe3O4 Nanoparticles Influenced by Magnetic Field and Protein

Magnetic nanoparticles (MNPs) used in bio-application have accelerated the development of “theranostics” which contains imaging, therapy and drug delivery. However, in a protein-rich physiological fluid, MNPs are ineluctable to a contact with protein to form “protein corona”, which will significantly change the physicochemical properties of the particles and their biological behavior. Therefore, we investigated the influence of protein and static magnetic field (SMF) on the cytotoxicity and cellular uptake of MNPs. The Fe3O4 nanoparticles (Fe3O4 NPs) were synthesized by solvothermal method with a mean diameter of [Formula: see text][Formula: see text]nm functionalized with carboxyl groups. After a period of 12[Formula: see text]h incubation in complete medium (CM), the wrapping of the Fe3O4 NPs by protein adsorption resulted in about 40-nm increase of the hydrodynamic size. Their stability in CM and water solution did not broaden significantly over time, which is exactly opposite in serum-free media (SFM). When transferred to SFM with high ionic-strength, the Fe3O4 NPs aggregated and settled quickly. We explore that the cell viability was decreased in proportion to the concentration and incubating time of Fe3O4 NPs, the absence of FBS and the presence of SMF exposure, respectively. Quantitative analysis showed that cells could incorporate more NPs in SFM, about five-fold more than in CM. In addition, it is obvious that exposure to SMF resulted in more cellular uptake both in CM and SFM. Our results demonstrated that Fe3O4 NPs in SFM and SMF exposure would settle down to cell rapidly, which caused more cellular uptake and higher cytotoxicity.