In this study, we have demonstrated that white adipocytes are less prone to apoptotic stimuli, including in vitro TNF-a exposure and serum deprivation, and in vivo starvation, than brown adipocytes. A relevant finding was the high expression level of the anti-apoptotic Bcl-2 protein in white adipocytes when compared to brown fat cells either in unstimulated conditions or after exposure to TNF-a plus CHX. Interestingly, the levels of Bcl-2 have been observed to increase during 3T3-L1 adipogenesis,9,12 which was accompanied by an increased resistance to apoptosis.9 Noteworthy, the death signaling pathway (i.e., the caspase-8-induced Bid cleavage to the active tBid, with Bax activation, cytochrome c release and PARP cleavage, that in turn activate the major execution caspase, caspase-3) was triggered specifically and markedly in brown adipocytes.
White adipocytes are less prone to apoptotic stimuli than brown adipocytes in rodent
BRACALE, Renata;
2006-01-01
Abstract
In this study, we have demonstrated that white adipocytes are less prone to apoptotic stimuli, including in vitro TNF-a exposure and serum deprivation, and in vivo starvation, than brown adipocytes. A relevant finding was the high expression level of the anti-apoptotic Bcl-2 protein in white adipocytes when compared to brown fat cells either in unstimulated conditions or after exposure to TNF-a plus CHX. Interestingly, the levels of Bcl-2 have been observed to increase during 3T3-L1 adipogenesis,9,12 which was accompanied by an increased resistance to apoptosis.9 Noteworthy, the death signaling pathway (i.e., the caspase-8-induced Bid cleavage to the active tBid, with Bax activation, cytochrome c release and PARP cleavage, that in turn activate the major execution caspase, caspase-3) was triggered specifically and markedly in brown adipocytes.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.