Effects of Electric Cortical Stimulation (ECS) and Transcranial Direct Current Stimulation (tDCS) on Rats With a Traumatic Brain Injury

Abstract

Objective To evaluate the effects of electric cortical stimulation (ECS) and transcranial direct current stimulation (tDCS) on motor and cognitive function recovery and brain plasticity in focal traumatic brain injury (TBI) of rats model.MethodsForty rats were pre-trained to perform a single pellet reaching task (SPRT), rotarod test (RRT), and Y-maze test for 14 days, then a focal TBI was induced by a weight drop model on the motor cortex. All rats were randomly assigned to one of the three groups: anodal ECS (50 Hz and 194 μs) (ECS group), tDCS (0.1 mA, 50 Hz and 200 μs) (tDCS group), and no stimulation as a control group. Four-week stimulation, including rehabilitation, was started 3 days after the operation. SPRT, RRT, and Y-maze were measured from day 1 to day 28 after the TBI was induced. Histopathological and immunohistochemistry staining evaluations were performed at 4 weeks.ResultsSPRT was improved from day 7 to day 26 in ECS, and from day 8 to day 26 in tDCS compared to the control group (p<0.05). SPRT of ECS group was significantly improved on days 3, 8, 9, and 17 compared to the tDCS group. Y-maze was improved from day 8 to day 16 in ECS, and on days 6, 12, and 16 in the tDCS group compared to the control group (p<0.05). Y-maze of the ECS group was significantly improved on day 9 to day 15 compared to the tDCS group. The c-Fos protein expression was better in the ECS group and the tDCS group compared to the control group.ConclusionElectric stimulation in rats modified with a focal TBI is effective for motor recovery and brain plasticity. ECS induced faster behavioral and cognitive improvements compared to tDCS during the recovery period of rats with a focal TBI.

Cortical Electrical Stimulation Ameliorates Traumatic Brain Injury-Induced Sensorimotor and Cognitive Deficits in Rats

“…In the current study, we found that 4 weeks of CES treatment of TBI rats improved the recovery of locomotor function. These results parallel the findings from another TBI animal study, showing that CES is effective for the recovery of motor function, spatial memory (Yu et al, 2018 ). In addition, it has been found that the 100 Hz CES combined with daily motor training for 9 weeks significantly improved forelimb motor performance (Jefferson et al, 2016 ), encouraging further research into its therapeutic potential.…”

Beyond the target area: an integrative view of tDCS-induced motor cortex modulation in patients and athletes

“…4b) associated to physical therapy [143]. This preliminary human result and some from animal studies [119, 227] have supported the potential benefit and safety of DCS after TBI. However, the diffuse damage associated with TBI, making it difficult to determine the stimulation target, could limit the use of tDCS as a therapeutic modality to improve motor outcomes after TBI.…”

“…Anodal stimulation hyperpolarizes apical dendritic layer (blue) and depolarize soma (red) of pyramidal cortical neurons. c The resultant tDCS effects reported are related to modified excitability [60, 63, 76, 118], neuroplasticity [8, 44, 45, 119] and neural network oscillation [67, 77, 120]. d Simulation of four brain networks during tDCS with a connectivity (or adjacency) matrix between a given pair of regions by connectivity strength [100, 102]…”

Optogenetic Modulation for the Treatment of Traumatic Brain Injury

“…This observed endogenous plasticity can be further investigated and manipulated using precise electrical modulation. To date, several methods have been explored to induce or accelerate functional and adaptive recovery in TBI patients, including both invasive (eg, electrical cortical stimulation [ECS]) and noninvasive (eg, transcranial magnetic stimulation [TMS], transcranial direct current stimulation, and pharmacologic) methods, each mediating an upregulation in plasticity following TBI [16][17][18][19][20]. However, animal studies and clinical trials involving the use of these interventions are scarce, and such approaches are often cell type indiscriminate, invasive, and render surrounding tissues susceptible to damage [21,22].…”