Adipose cell apoptosis: death in the energy depot

Apoptosis is critical for mammalian tissue homeostasis, and its disruption has been linked to a wide variety of disorders, including cancer, neurodegenerative disease, autoimmune disease and diabetes. This review will focus on recent investigations that have begun to address the potential role of apoptosis in adipose tissue growth. Evidence for apoptosis occurring in mature adipocytes has been obtained through the use of in vitro cell culture models as well as in vivo studies in rodents and humans. Preadipocytes, fibroblast-like adipocyte precursor cells, can also undergo apoptotic cell death. As they differentiate, preadipocytes acquire a relative resistance to apoptosis. The levels of the cell survival proteins Bcl-2 and neuronal apoptosis inhibitory protein (NAIP) have been observed to increase during adipogenesis. Further research on the effect of apoptosis on adipose tissue cellularity should clarify its influence on adipose tissue mass and distribution.