Electrical stimulation improved cognitive deficits associated with traumatic brain injury in rats.

Introduction: Cognitive deficits associated with traumatic brain injury (TBI) reduce patient quality of life. However, to date, there have been no effective treatments for TBI-associated cognitive deficits. In this study, we aimed to determine whether electrical stimulation (ES) improves cognitive deficits in TBI rats.

Methods: Rats were randomly divided into three groups: the Sham control group, electrical stimulation group (ES group), and No electrical stimulation control group (N-ES group). Following fluid percussion injury, the rats in the ES group received ES treatment for 3 weeks. Potent cognitive function-relevant factors, including the escape latency, time percentage in the goal quadrant, and numbers of CD34 cells, von Willebrand Factor (vWF ) vessels, and circulating endothelial progenitor cells (EPCs), were subsequently assessed using the Morris water maze (MWM) test, immunohistochemical staining, and flow cytometry.

Results: Compared with the rats in the N-ES group, the rats in the ES group exhibited a shorter escape latency on day 3 (=.025), day 4 (=.011), and day 5 (=.003), as well as a higher time percentage in the goal quadrant (=.025) in the MWM test. After 3 weeks of ES, there were increased numbers of CD34 cells (=.008) and vWF vessels (=.000) in the hippocampus of injured brain tissue in the ES group compared with those in the N-ES group. Moreover, ES also significantly increased the number of EPCs in the peripheral blood from days 3 to 21 after TBI in the ES group (<.05).

Conclusions: Taken together, these findings suggest that ES may improve cognitive deficits induced by TBI, and this protective effect may be a result, in part, of enhanced angiogenesis, which may be attributed to the increased mobilization of EPCs in peripheral blood.