稳态强磁场的细胞生物学效应

随着科学技术的发展以及稳态强磁场在医疗诊断中的广泛应用,人们接触到1 T以上稳态强磁场的机会越来越多,稳态强磁场对人体健康的潜在影响也备受关注.虽然目前由于实验条件的限制,稳态强磁场对动物以及人体的研究报道依然有限,但是细胞作为生物体的基本单位,其研究相对较多.然而由于实验中磁场参数、细胞类型等各种因素的不同,使得稳态强磁场对细胞的影响在不同的研究中存在着差异.因此,本文不仅总结和分析了国内外1 T以上稳态强磁场细胞生物学效应的相关研究,包括细胞取向、增殖、微管和纺锤体等,而且对现有研究结果进行比较和概括,并对可能造成实验差异的因素进行分析,例如磁场强度和细胞类型等,从而为下一步研究稳态强磁场下的细胞生物学效应提供基础和依据.

Biological effects on cells in strong static magnetic field

With the development of technology and the widespread use of high static magnetic fields (SMFs) in medical diagnosis, such as MRI (magnetic resonance imaging) in hospitals, patients have more and more chances to encounter high SMFs (higher than 1 T), which invokes increasing public concerns about human health. However, due to the experimental limitations, there are very few studies of high SMFs (above 1 T) on animals and human bodies. In contrast, cell, as a basic unit of various organisms, is the primary research target for most researches of the biological effects under the action of magnetic fields. However, due to the differences in magnetic field parameter, exposure condition and cell type, there are diverse experimental outcomes reported by individual studies in the literature. Here in this review, we summarize the results about the cellular effects under SMFs above 1 T, including changes of cell orientation, cell proliferation, microtubule and mitotic spindle orientation, DNA and cell cycle. Moreover, we also compare and analyze the factors that could cause these experimental variations, including the differential effects of high SMFs on cell type, such as cancer and non-cancer cells, as well as magnetic field intensity-induced experimental variations. The most well studied cellular effects are SMF-induced cell and polymer orientation changes, and the cellular composition is a key factor that determines the exact orientation of a cell in an SMF. For example, the normal red blood cell is aligned parallelly to the SMF direction, but the whole bull sperm is aligned perpendicularly to the SMF direction. Among the magnetic field parameters, the magnetic field intensity is especially critical. The red blood cells can only be partially aligned by 1 T SMF, but an 8 T SMF could align the red blood cells 100% along the magnetic direction. Overall, the biological research of high SMFs above 1 T, especially above 10 T, is still at an initial stage. Biological experiments in high SMFs above 20 T are especially lacking. This review could help provide some biological bases for future high SMF investigations, which is important not only for the basic understanding of the biological effects of high SMFs, but also for the applications of high SMFs in medicine, such as high field MRI.