Abstract P111: Effects Of Magnetic Field On Abca1-mediated Cellular Lipid Release And Adult Brain Cell Generation In Mice

Aim: This project aims to explore a novel magnetic field (MF) health care based on the cholesterol metabolism. Methods: Mouse peritoneal macrophages foam cells were incubated in CO 2 -independent culture medium containing apoA-I and were exposed in a MF (0.4 T) using the electromagnet of EPR spectrometer. C57BL/6N mice (8 week-old) were peritoneally injected F-ara-EdU (133μg/g mouse body weight) then exposed to MF under the identical condition. Mouse plasma, cerebrospinal fluid, liver and brain were harvested on the 28 th day. Lipoprotein profiles were examined enzymatic detection followed by a gel-permeable-HPLC (Skylight Biotech Inc.). Amyloid β40 and β42 levels were determined by WAKO ELISA kit. Fixed mouse brain sections (40um) were prepared by Leica CM1900 cryostat. Alexa fluor® 488 conjugates were link to F-ara-EdU by a click chemistry method and fluor positive nucleus images were captured by a confocal super resolution SpinSR10 (Olympus, Inc.). Results: ABCA1-apoA-I mediated cellular cholesterol release was not affected or reduced by the exposure in the MF of 0.4 T. The Pcsk9 expression showed significant reduction in the hepatocytes. Reduction of Abca1 expression and increase of Scarb1 were obtained non significantly. The newly generated hippocampal dentate gyrus cells in the control mice group and the MF exposed group were 1.6±1.17, and 0.47±0.62 cells per dentate gyrus section, respectively (P=0.003) despite bulk of new cells in olfactory bulbs in the both groups. Discussions: No substantial increase in cellular cholesterol export was observed by MF irradiation of mouse peritoneal macrophage cells. In addition, the lipoprotein profile showed a decrease in HDL cholesterol even after 28 days. As a result of gene expression in the liver, a decrease in ABCA1 expression and an increase in SR-BI expression inferred reduction of HDL. The number of new cells detected in the granular zone and the subgranular zone in the dentate gyrus of the hippocampus was significantly reduced in the mice subjected to the MF treatment. In the future, it is necessary to investigate in detail whether these newborn cells are neuron or glial cells.