Scientists recently conducted a series of studies to test the biosafety and neurobehavioral effects of high static magnetic fields (SMF) of 33.0 Tesla using Steady High Magnetic’s self-designed biological research platform Field Facility (SHMFF). The experiments were carried out by Professor Xin Zhang’s team at the Hefei Institutes of Physical Sciences of the Chinese Academy of Sciences.
They have, for the first time, reported the biosafety of 30 Tesla level SMF and the neurobehavioral effects of 20 Tesla and 30 Tesla level SMF on healthy mice in the Magnetic Resonance Imaging Journal and European radiology.
In recent years, ultra-high field magnetic resonance imaging (MRI) has developed rapidly due to its significant advantage of high imaging resolution. 7 Tesla MRI has been clinically approved and 21.1 Tesla MRI has been used successfully in rodents. However, studies on the biosafety of high magnetic fields above 20 Tesla are still scarce, and there is still a gap in relevant studies above 30 Tesla.
Based on the previous biosafety study of 3.5-23.0 Tesla SMF, Xin Zhang’s group further increased the magnetic field intensity and shortened the exposure time. Healthy C57BL/6J mice were exposed to 7.0-33.0 Tesla SMF for one hour.
After exposure, all mice were regularly fed for two months. Except for a few indicators of metabolic and hepatic and hepatorenal functions affected by magnetic field, total blood count and organ coefficient on major organ histomorphology were not seriously affected. Most mice remained within the normal reference range.
Meanwhile, behavioral tests showed that high SMF relieved anxiety and improved social and spatial memory in mice within two months of exposure.
In addition, behavioral studies of healthy mice exposed to a magnetic field of 3.5 to 23.0 Tesla for two hours also revealed enhanced neurocognitive effects, which may be associated with increased expression of calcium-dependent protein kinase II/calmodulin in mouse hippocampus.
Zhang’s group further found that 7 Tesla SMF could effectively alleviate symptoms in depressed mice. These results not only provide useful safety information for the development of ultra-high MRI, but may also indicate that high SMF has the potential for future antidepressant therapy.
Reference: “Short and long term effects of ultra-high magnetic fields from 3.5 to 23.0 Tesla on the behavior of mice” by Md Hasanuzzaman Khan, Xinfeng Huang, Xiaofei Tian, Changjie Ouyang, Dongmei Wang, Shuang Feng, Jutao Chen, Tian Xue, Jin Bao and Xin Zhang, March 16, 2022, European Radiology.
This study was supported by the National Key Research and Development Program of the Ministry of Science and Technology, the National Natural Science Foundation of China, the President’s Fund of Hefei Physical Science Institutes, etc.