A new drug may help treat stroke

Distinguished Professor Michael Chopp, of the Department of Physics, leads an acclaimed group of researchers studying stroke. One of their main goals is to extend the brief therapeutic window when the brain can easily recover from a lack of oxygen (ischemia). Typically, a patient suffering from a recent stroke is treated using tissue plasnimogen activator (tPA), a protein involved in breaking down blood clots. Chopp’s team tested the hypothesis that a second drug, VELCADE, when given in combination with tPA, is more effective than VELCADE or tPA alone. VELCADE is a proteasome inhibitor, a drug that blocks the breakdown of proteins. Chopp’s team presents evidence for the mechanism underlying VELCADE’s effect: it blocks the decay of nitric oxide synthase, the enzyme responsible for production of nitric oxide, an important molecule for protecting neurons in the brain from damage due to ischemia (neuroprotection). In a paper published in the May issue of the journal Stoke, they report how a Combination Treatment with VELCADE and Low-Dose Tissue Plasminogen Activator Provides Potent Neuroprotection in Aged Rats after Embolic Focal Ischemia (Volume 41, Pages 1001-1007, 2010). They conclude that “treatment with VELCADE exerts a neuroprotective effect in aged rats after stroke. The combination of VELCADE with the low-dose tPA further amplifies the neuroprotective effect. Endothelial nitric oxide synthase at least partly contributes to VELCADE-mediated neuroprotection after stroke.” One of the coauthors on this paper is Ben Buller, a graduate student in the Biomedical Sciences: Medical Physics PhD program.