Evaluation of Apoptotic Caspase-3 Immunopositivity in Human Model of Asphyxial Death.

The pathological mechanisms underlying the ligature mark in hanging involve the skin layers and an ischemic mechanism. The apoptotic process develops whenever ischemic mechanisms affect the dermal and epidermal layers. Effector caspase-3 appears to play a crucial role in both acute and chronic pressure-induced skin ischemia. The aim of this study is to identify the role of caspase-3 as a marker of supravitality in the diagnosis of premortem hanging. Skin samples from ligature marks in hanging cases were collected to investigate this apoptotic process. The caspase-3 levels in compressed skin were significantly higher compared to those found in healthy skin (p < 0.005). The apoptotic process in ischemic epidermal cells begins with stable mechanical stress, as seen in the hanging model. Caspase-3 expression seems to vary from minutes after the initial stress input. Caspase-3 activation is an ATP-dependent process and can only occur if the victim was alive before the pressure was applied. Caspase-3 is a reliable marker of supravitality in ligature marks in premortem hanging cases.