title: Can the 'yin and yang' BDNF hypothesis be used to predict the effects of rTMS treatment in neuropsychiatry?
abstract: Repetitive transcranial magnetic stimulation (rTMS) is a novel technique of non-invasive brain stimulation which has been used to treat several neuropsychiatric disorders such as major depressive disorder, chronic pain and epilepsy. Recent studies have shown that the therapeutic effects of rTMS are associated with plastic changes in local and distant neural networks. In fact, it has been suggested that rTMS induces long-term potentiation (LTP) and long-term depression (LTD) - like effects. Besides the initial positive clinical results; the effects of rTMS are still mixed. Therefore new tools to assess the effects of plasticity non-invasively might be useful to predict its therapeutic effects and design novel therapeutic approaches using rTMS. In this paper we propose that brain-derived neurotrophic factor (BDNF) might be such a tool. Brain-derived neurotrophic factor is a neurotrophin that plays a key role in neuronal survival and synaptic strength, which has also been studied in several neuropsychiatric disorders. There is robust evidence associating BDNF with the LTP/LTD processes, and indeed it has been proposed that BNDF might index an increase or decrease of brain activity - the 'yin and yang' BDNF hypothesis. In this article, we review the initial studies combining measurements of BDNF in rTMS clinical trials and discuss the results and potential usefulness of this instrument in the field of rTMS.
authors.affiliation: Berenson-Allen Center for Noninvasive Brain Stimulation, Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Avenue, KS 430, Boston, MA 02215, USA.
authors.forename: Andre Russowsky
authors.initials: AR
authors.lastname: Brunoni
authors.forename: Paulo Sergio
authors.initials: PS
authors.lastname: Boggio
authors.forename: Felipe
authors.initials: F
authors.lastname: Fregni
mesh_terms: D001921:Brain / Q000473:pathology; D019208:Brain-Derived Neurotrophic Factor / Q000502:physiology*; D002986:Clinical Trials as Topic; D003865:Major Depressive Disorder / Q000628:therapy; D004827:Epilepsy / Q000628:therapy; D006801:Humans; D008954:Models, Biological; D008962:Models, Theoretical; D009414:Nerve Growth Factors / Q000378:metabolism; D059408:Pain Management; D011570:Psychiatry / Q000379:methods; D050781:Transcranial Magnetic Stimulation / Q000379:methods*; D016896:Treatment Outcome
chemical_list: D019208:Brain-Derived Neurotrophic Factor; D009414:Nerve Growth Factors