Figure 1.

PBI-05204 treatment increases BDNF protein levels and activation of TrkB receptors. A, Brain slices were treated with varying concentrations of PBI-05204 for 2 d, after which tissue lysates were analyzed by ELISA for total BDNF protein content. The pan-caspase inhibitor Boc-D-FMK (“Boc”) also provides neuroprotection (Fig. 2G) but had no effect on BDNF levels. B, The cardiac glycoside oleandrin, the principal bioactive component of PBI-05204, also increased BDNF expression in brain slices in a concentration-dependent manner. C, Representative immunoblot showing PBI-05204 induction of TrkB autophosphorylation in the same concentration range as for BDNF induction in A. In the second lane, 200 ng/ml BDNF is the positive control. D, Densitometric analysis of relative levels of TrkB phosphorylation (“Phospho/total TrkB”) induced by PBI-05204 averaged over six independent runs. *p < 0.05 by Student's t test.