Effects of transcranial direct current stimulation on brain cytokine levels in rats

Abstract

Transcranial direct current stimulation (tDCS) has shown therapeutic potential to mitigate symptoms of various neurological disorders. Studies from our group and others used rodent models to demonstrate that tDCS modulates synaptic plasticity. We previously showed that 30 min of 0.25 mA tDCS administered to rats induced significant enhancement in the synaptic plasticity of hippocampal neurons. It has also been shown that tDCS induces expression of proteins known to mediate synaptic plasticity. This increase in synaptic plasticity may underly the observed therapeutic benefits of tDCS. However, the anti-inflammatory benefits of tDCS have not been thoroughly elucidated. Here we report that three sessions of tDCS spaced 1–3 weeks apart can significantly reduce levels of several inflammatory cytokines in brains of healthy rats. Rats receiving tDCS experienced enhanced synaptic plasticity without detectable improvement in behavioral tests or significant changes in astrocyte activation. The tDCS-mediated reduction in inflammatory cytokine levels supports the potential use of tDCS as a countermeasure against inflammation and offers additional support for the hypothesis that cytokines contribute to the modulation of synaptic plasticity.

Anti-Inflammatory and Cortical Responses after Transcranial Direct Current Stimulation in Disorders of Consciousness: An Exploratory Study

“…Consistently applying multiple tDCS sessions can potentially modulate these biological cascades, determining a significant reduction in angiopoietin-2 and IP-10, for example. The role of tDCS in neuroinflammation has been previously addressed in animal models [ 59 , 60 ] and other neurological conditions, such as bipolar disorders [ 35 ], leading to the hypothesis that tDCS can influence cytokine release in the brain and reduce neural inflammation. Here, importantly, we showed that some biomarkers, i.e., TNFα and IP-10, directly correlate with behavioural changes after the tDCS, as measured by the CRS-R scale.…”

Combined repetitive transcranial magnetic stimulation and gut microbiota modulation through the gut–brain axis for prevention and treatment of autism spectrum disorder

“…A previous study provided evidence in favor of the excitation/inhibition imbalance hypothesis in ASD and related neurodevelopmental disorders while revealing that its nature is region-specific with distinct pre- and postsynaptic mechanisms. In the hippocampus, disproportionate expression of gamma-aminobutyric acid (GABA)-A receptor dominates, whereas excessive GABA/glutamate ratios are the hallmark of changes in the prefrontal cortex and striatum ( 19 ).…”