RESEARCH ARTICLE Relevance of Post-Stroke Circulating BDNF Levels as a Prognostic Biomarker of Stroke Outcome. Impact of rt-PA Treatment

The recombinant form of tissue plasminogen activator (rt-PA) is the only curative treatment for ischemic stroke. Recently, t-PA has been linked to the metabolism of brain-derived neu-rotrophic factor (BDNF), a major neurotrophin involved in post-stroke neuroplasticity. Thus, the objective of our study was to investigate the impact of rt-PA treatment on post-stroke cir-culating BDNF levels in humans and in animals. Serum BDNF levels and t-PA/plasmin activity were measured at hospital admission and at up to 90 days in stroke patients receiv-ing (n = 24) or not (n = 14) rt-PA perfusion. We investigated the relationships between serum BDNF with concurrent t-PA/plasmin activity, neurological outcomes and cardiovas-cular scores at admission. In parallel, serum BDNF levels and t-PA/plasmin activity were assessed before and after (1, 4 and 24h) the induction of ischemic stroke in rats. Our study revealed higher serum BDNF levels and better neurological outcome in rt-PA-treated than non-treated patients. However, serum BDNF levels did not predict stroke outcome when the whole cohort of stroke patients was analyzed. By contrast, serum BDNF levels when measured at admission and at day 90 correlated with cardiovascular scores, and those a