Background:

CEP-1347, also called KT 7515, is an inhibitor of the c-Jun N-terminal kinase (JNK) signaling pathway, with an IC50 value for JNK1 activation of 20 ± 2 nM in rat embryonic motoneurons [1].

The JNK pathway, also known as the stress-activated protein kinase (SAPK) pathway, is one of the signaling cascades that mediate the apoptotic death in response to a variety of stressful stimuli. JNK activation by phosphorylation is important for neuronal cell death after injury in vivo and after trophic factor withdrawal in vitro [2].

CEP-1347 induced neuronal survival. JNK1 activity in untreated cell cultures increased approximately fourfold within 24 hr after plating. As early as 15 min after the application of CEP-1347 at 500 nM, the activity of JNK1 sharply decreased to