The Role of Astrocytes in Deep Brain Stimulation

Abstract

Deep brain stimulation (DBS) has been used in the treatment of many neurological disorders already some decades and its clinical benefit has frequently been marked. The mechanism by which DBS affects neuronal signalling is still elusive and extensively studied. Although most studies are only concerned with the effect that DBS has on neurons, it is unlikely that DBS solely affects these cells in the brain. It is hypothesised that DBS also affects glial cells and that these cells underlie, at least partly, the beneficial effects of DBS on brain function. Since DBS is thought to interfere with neural network activity and astrocytes are deeply involved in the regulation of neural network signalling, astrocytes seem the perfect candidates. In this review, the role of astrocytes in the working mechanism of DBS is investigated. It is shown that astrocytes can be triggered to release signalling proteins and to proliferate upon high-frequency stimulation, such as DBS. Interestingly, it has been shown that astrocytes after proliferation might differentiate in neural stem cells as a result of the electrical stimulation. The line of evidence for the contribution of astrocytes in the mechanism of DBS is still very thin, but compelling and therefore, much more work has to be done in this field. Future studies need to point out to what extent astrocytes play a role in the effect of DBS on brain function and the therapeutic effect of this. If astrocytes are truly involved in the mechanism of DBS, this has important implications for the future application of the method.