Effect of weak combined static and extremely low-frequency alternating magnetic fields on spatial memory and brain amyloid-β in two animal models of Alzheimer’s disease

Abstract

Subchronic effect of a weak combined magnetic field (MF), produced by superimposing a constant component, 42 µT and an alternating MF of 0.08 µT, which was the sum of two frequencies of 4.38 and 4.88 Hz, was studied in olfactory bulbectomized (OBE) and transgenic Tg (APPswe, PSEN1) mice, which were used as animal models of sporadic and heritable Alzheimer's disease (AD) accordingly. Spatial memory was tested in a Morris water maze on the following day after completion of training trials with the hidden platform removed. The amyloid-β (Aβ) level was determined in extracts of the cortex and hippocampus of mice using a specific DOT analysis while the number and dimensions of amyloid plaques were detected after their staining with thioflavin S in transgenic animals. Exposure to the MFs (4 h/day for 10 days) induced the decrease of Aβ level in brain of OBE mice and reduced the number of Aβ plaques in the cortex and hippocampus of Tg animals. However, memory improvement was revealed in Tg mice only, but not in the OBE animals. Here, we suggest that in order to prevent the Aβ accumulation, MFs could be used at early stage of neuronal degeneration in case of AD and other diseases with amyloid protein deposition in other tissues.

Hippocampus Metabolic Disturbance and Autophagy Deficiency in Olfactory Bulbectomized Rats and the Modulatory Effect of Fluoxetine

“…In the present study, OBX rats displayed a significantly increased hyperemotionality score when experiencing four mild stimuli. Similarly to previous studies [23,24], we observed that OBX rats exhibited significantly prolonged escape latencies on day 3 and day 5 in the MWM navigation test, and shortened time and movement distance percentage in the target quadrant in the probe test, which indicates the spatial memory deficits in OBX rats. Chronic fluoxetine treatment relieved the hyperemotional response, but could not ameliorate impairment in learning and memory in OBX rats.…”

Preventive measures to reduce harmful effects produced by electromagnetic radiation on health

“…Влияние, оказываемое КНЧ на нейродегенеративные заболевания, описано Benassi et al [13] на примере болезни Паркинсона, когда было отмечено значительное ухудшение окислительно-восстановительного потенциала и содержания тиола в клетках SH-SY5Y, а также рост карбонилирования белков. Подобные явления описывались Bobkova et al [14], которые отметили изменения в пространственной памяти и мозговом амилоиде-β на двух животных моделях с заболеванием Альцгеймера. В обзоре Terzi et al [15] суммированы добавочные нейродегенеративные эффекты.…”

Preventive measures to reduce harmful effects produced by electromagnetic radiation on health

“…Carruba et al [12] demonstrated experimentally that low-frequency pulse by mobile phones triggered EEG evoked potentials in human volunteers. Effects produced by ELF on neurodegenerative diseases were shown by Benassi et al [13] regarding Parkinson's disease, with significantly impaired redox homeostasis and thiol content in SH-SY5Y cells, and an increase in protein carbonylation; and by Bobkova et al [14] with changes in spatial memory and brain amyloid-β in two animal models of Alzheimer's disease. A review by Terzi et al [15] summarizes additional neurodegenerative effects.…”