👤 Joanna Wyszkowska

Extremely low-frequency electromagnetic field (ELF-EMF) therapy is gaining attention for its potential benefits in treating neurodegenerative conditions. However, the underlying molecular mechanisms responsible for the possible protective effects of ELF-EMF remain unclear. Our previous research revealed that ELF-EMF exposure can establish a new "set-point" for stress responses, with outcomes dependent on field intensity. Stress hormones have been shown to modulate hippocampal function and plasticity. Therefore, our study aimed to assess how ELF-EMF exposure affects the expression of transcripts related to hippocampal plasticity, including genes related to neurogenesis (BDNF, TrkB, GAP43), synaptic activity (PSD95, SYN1), and cell survival (Bcl-2, Bcl-xL, Bak1). Adult rats were exposed to ELF-EMF (50 Hz) at 1 mT and 7 mT intensities for three 7-day periods, 1 h/day, with 3-week break between each cycle. A subset of animals was sacrificed after each exposure to collect hippocampi. The relative expression of neural/synaptic genes and anti-/pro-survival factors was measured by real-time quantitative polymerase chain reaction. Our findings indicate that ELF-EMF exposure modulates mRNA expression of neural/synaptic genes and anti-/pro-survival factors. The direction and dynamics of changes depend on ELF-EMF intensity and the number of exposures. "Low-intensity" ELF-EMF (1 mT) increased pro-neuroplastic factors expression, while "high-intensity" ELF-EMF (7 mT) decreased them. In summary, "low-intensity" ELF-EMF enhances adaptive processes like neuroplasticity by eliciting a mild stress response, while "high-intensity" exposure disrupts homeostasis and brain function by inducing severe stress. Our findings indicate that the overall effects of ELF-EMF depend on the intricate interplay between stress reactions and long-term brain plasticity. Show less