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We established three types of thrombosis models to explore the effects of the static magnetic field (SMF) on thrombosis in rats and mice with three different MF intensities. In the carrageenan‐induced thrombosis model in rats, the SMF treatments reduced the black tail length of rats, extracorporeal thrombus, and the mass of wet and dry thrombus, and improved the coagulation index value. In FeCl3‐induced arterial thrombosis model in rats, the SMF treatment showed some anti‐thrombotic effects. More specifically, the SMF treatment affected rodent blood pressure, plasma plasminogen activator inhibitor, tissue‐type plasminogen activator, thrombus mass, and thrombus protein content. In the adrenaline‐induced thrombosis model in mice, the SMF treatment had certain effects on the diameter and blood flow velocity of mouse auricle microcirculation in fine veins and arteries. Overall, the highest MF intensities we tested, 20–150 mT, showed a trend of anti‐thrombotic effect, indicating that the moderate‐intensity SMF might serve as a potential treatment for clot‐related diseases in the future. Bioelectromagnetics. 2020;41:52–62 © 2019 Bioelectromagnetics Society.

Although some studies have shown that some static magnetic fields (SMFs) can promote wound healing in diabetic mice, it is not clear whether the other diabetes complications, such as liver disease and diabetic nephropathy, can also be alleviated. Here, we constructed two simple magnetic plates using neodymium permanent magnets to examine the comprehensive effects of moderate SMFs on genetically obese leptin receptor-deficient db/db diabetic mice. We found that although the blood glucose was not obviously reduced by these two SMF settings, both of the glycated serum protein (GSP) and malondialdehyde (MDA) levels were significantly decreased (Cohen’s d = 2.57–3.04). Moreover, the wound healing, liver lipid accumulation, and renal defects were all significantly improved by SMF treatment (Cohen’s d = 0.91–2.05). Wound tissue examination showed obvious nuclear factor erythroid 2-related factor 2 (NRF2) level decrease (Cohen’s d = 2.49–5.40) and Ki-67 level increase (Cohen’s d = 2.30–3.40), indicating decreased oxidative stress and increased cell proliferation. In vitro cellular studies with fibroblast NIH3T3 cells showed that SMFs could reduce high glucose-induced NRF2 nucleus translocation (Cohen’s d = 0.87–1.15) and cellular reactive oxygen species (ROS) elevation (Cohen’s d = 0.92), indicating decreased oxidative stress. Consequently, high glucose-induced impairments in cell vitality, proliferation, and migration were all improved by SMF treatment. Therefore, our results demonstrate that these simple SMF devices could effectively reduce oxidative stress in diabetic mice and may provide a cost-effective physical therapy strategy to alleviate multiple diabetic complications in the future.

Exposure of humans and animals to microgravity in spaceflight results in various deleterious effects on bone health. In addition to microgravity, the hypomagnetic field (HyMF) is also an extreme environment in space, such as on the Moon and Mars; magnetic intensity is far weaker than the geomagnetic field (GMF) on Earth. Recently, we showed that HyMF promoted additional bone loss in hindlimb unloading–induced bone loss, and the underlying mechanism probably involved an increase of body iron storage. Numerous studies have indicated that bone loss induced by mechanical unloading can be largely restored after skeletal reloading in GMF conditions. However, it is unknown whether this bone deficit can return to a healthy state under HyMF condition. Therefore, the purpose of this study is to examine the effects of HyMF on the recovery of microgravity‐induced bone loss, and illustrates the changes of body iron storage in this process. Our results showed that there was lower bone mineral content (BMC) in the HyMF reloading group compared to the GMF reloading group. Reloaded mice in the HyMF condition had a worse microstructure of femur than in the GMF condition. Femoral mechanical properties, including elastic modulus, stiffness, and ultimate stress, were poorer and toughness was higher in the HyMF group compared with the GMF group. Simultaneously, more iron content in serum, the tibia, liver, and spleen was found under HyMF reloading than GMF reloading. The iron chelator deferoxamine mesylate (DFO) decreased the iron content in the bone, liver, and spleen, and significantly relieved unloading‐induced bone loss under HyMF reloading. These results showed that HyMF inhibits the recovery of microgravity‐induced bone loss, probably by suppressing the elevated iron levels’ return to physiological level. © 2019 American Society for Bone and Mineral Research.

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