Phosphorylation of Thr(1495) of nestin in a mouse model of cerebral ischemia and reperfusion damage.

Nestin, a class VI intermediate filament protein, is expressed by neuronal progenitor cells in the subventricular zone (SVZ). In the present study, we analyzed the nestin expression and phosphorylation levels in nerve cells in a mouse model of cerebral ischemia and reperfusion. C57BL/6 mice were subjected to three-vessel occlusion for 14min, and were killed either 1 or 4 days after the procedure. The percentages of cells in the SVZ that were positive for nestin, Thr(1495)-phosphorylated nestin or Ki67 did not significantly differ between the ischemic reperfusion and sham groups. Conversely, in the striatum and cornu ammonis 2 (CA2) regions, the mice at 4 days after ischemic reperfusion showed significantly higher numbers and percentages of nerve cells that were positive for nestin, Thr(1495)-phosphorylated nestin and Ki67 compared to results from the other groups. To our knowledge, this is the first description of phosphorylated nestin expression in neural progenitor cells in the SVZ of adult mice. In this cerebral ischemia and reperfusion mouse model, cells positive for Thr(1495)-phosphorylated nestin were increased in the striatum and CA2 field of the hippocampus; suggesting that nestin phosphorylation may play an important role in mitotically active neuronal progenitor cells.