BDNF and Alzheimer disease: Similarly, Wen and coworkers [209] found that tert-butyl hydroperoxide treatment resulted in AD-like neuronal damage, but secretion from bone marrow mesenchymal stem cells, pretreated with berberine, prevented these neurodegenerative features by increasing BDNF and Bcl-2 levels and reducing Bax and caspase-3 activity.