Dejneka, A. | Search bioRxiv

bioRxiv2022

No evidence for detectable direct effects of magnetic field on cellular autofluorescence

Dramatically increased levels of electromagnetic radiation in the environment have raised concerns over the potential health hazards of electromagnetic fields. Various biological effects of magnetic fields have been proposed. Despite decades of intensive research, the molecular mechanisms procuring cellular responses remain largely unknown. The current literature is conflicting with regards to evidence that magnetic fields affect functionality directly at cellular level. Therefore, a search for potential direct cellular effects of magnetic fields represents a cornerstone that may propose an explanation for potential health hazards associated with magnetic fields. Recently, it was postulated that autofluorescence of HeLa cells is magnetic field sensitive, relying on single-cell imaging kinetic measurements. Here, we explore the utility of this approach by undertaking a screen for magnetic sensitivity of cellular autofluorescence in statistically relevant numbers (90-107) of HeLa cells. We did not observe any changes in cellular autofluorescence decay, when a modulated magnetic field was applied. We present a number of arguments indicating weak points in the analysis of magnetic field effects based on the imaging of cellular autofluorescence decay. Our work indicates that new methods are required to elucidate the effects of magnetic fields at the cellular level.

cell biology↗

bioRxiv2020

Effects of High Magnetic Fields on 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, ROS and drugs. We derive and solve the equation describing diffusion of such biologically active molecules in the presence of a MF as well as reveal the underlying mechanism of the MF effect on diffusion. We find 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 a 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 a MF opens new avenues for experimental studies foreseeing numerous biomedical applications.

biophysics↗