Figure 1.

Functional classification and domain architecture of caspases in SAH. Caspases are classified in SAH as pyroptotic or apoptotic caspases according to their function and domain structure. Apoptotic caspases can be further subdivided into initiator caspases and executioner caspases. The function of initiating caspases is to initiate apoptosis by activating executioner caspases. Furthermore, necroptosis occurs when caspase-8 is inhibited or knocked out. Caspase-12 is structurally like inflammatory caspases but may be activated by endoplasmic reticulum stress to participate in apoptosis. ^∗Until today, caspase-4, caspase-5, caspase-6, caspase-7, caspase-10, and caspase-11 have not been experimentally demonstrated in SAH, and their roles in SAH remain undefined. ^#Inhibition of caspase-8 activates necroptosis.