Role of endonucleases in renal tubular epithelial cell injury.

The study of cell death has emerged as an important and exciting area of research in cell biology. Although two kinds of cell death, apoptosis and necrosis, are recognized, one of the major advances in our understanding of cell death has been the recognition that the pathways traditionally associated with apoptosis may be very critical in the form of cell injury associated with necrosis. Renal tubular epithelial cell injury from ischemia or toxins has generally been regarded as a result of a necrotic form of cell death. We briefly describe recent evidence indicating apoptotic mechanisms including endonuclease activation in renal tubular injury and some mediators (oxidants, caspases and ceramide) which regulate this process. The pathway that is followed by the cell is dependent on both the nature and severity of insults, and it is likely that the cascades that lead to the apoptotic or necrotic mode of cell death are activated almost simultaneously and may share some common pathways.