FIG 3.

Rosiglitazone treatment increases caspase 3 activity and neuronal death in WNV-infected BSC. BSC were infected with WNV (10⁵ PFU per slice) in the presence/absence of 20 μM rosiglitazone (ROSI). Five (caspase 3) or 7 (IHC) days following infection, cultures were harvested for caspase 3 activity assays or were prepared for IHC. (A) In vitro caspase 3 activity assays showed that caspase 3 was elevated in WNV-infected BSC compared to uninfected controls and that rosiglitazone treatment augmented WNV-induced caspase 3 activity. The graph shows average caspase 3 activity (n = 4). Error bars indicate standard error of the mean. Statistical significance was determined using 2 sample, 2-tailed t tests (GraphPad). (B) Immunohistochemistry using antibodies for WNV (green) and the neuronal marker MAP2 (red) demonstrated that titer was increased in rosiglitazone slices and that this was accompanied by increased neuronal death identified by a decrease in MAP2 staining as well as shortening of neuronal processes (white arrows). Neurons costaining with WNV and MAP2 are highlighted (open arrows).