In another study, inhibition of CDK5 activity also attenuated p53-dependent apoptosis of hippocampal CA1 pyramidal neurons following cerebral ischemia; further, after transient global ischemia, the increased expression levels of Bax, PUMA, and activated caspase-3 were all decreased by roscovitine, a CDK5 inhibitor [52]. Here, TP53 is linked to brain ischemia.