Avtor/Urednik     Nipič, Damijan; Pirc, Aleš; Banič, Blaž; Šuput, Dušan; Milisav, Irina
Naslov     Preapoptotic cell stress response of primary hepatocytes
Tip     članek
Vir     Hepatology
Vol. in št.     Letnik 51, št. 6
Leto izdaje     2010
Obseg     str. 2140-51
ISSN     0270-9139
Jezik     eng
Abstrakt     Primary hepatocytes are an important in vitro model for studying metabolism in man. Caspase-9 and Bax are regulators of apoptotic pathway. Here we report on the translocation of procaspase-9 and Bax from cytoplasm to nuclei as well as on dispersion of mitochondria; these processes occur after isolation of primary hepatocytes. The observed changes appear similar to those at the beginning of apoptosis, however, the isolated hepatocytes are not apoptotic for the following reasons: (1) cells have a normal morphology and function; (2) the mitochondria are energized; (3) there is no apoptosis unless it is induced by e.g. staurosporine or nodularin. Staurosporine does not trigger apoptosis through activation of caspase-9, as its activity is detected later than that of caspase-3. We propose that the translocation of procaspase-9 and Bax into the nuclei reduces the ability to trigger apoptosis through the intrinsic apoptotic pathway. The shifts of procaspase-9 and Bax are reversible in the absence of the apoptotic trigger; the spontaneous reversion was confirmed experimentally for procaspase-9, while Bax shifted from the nuclei to the cytosol and mitochondria after the initiation of apoptosis. To distinguish this process from apoptosis, we call it pre-apoptotic cell stress response. It shares some features with apoptosis, however, it is reversible and apoptosis has to be induced in addition to this process. Knowledge on pre-apoptotic cell stress response is important for assessing the quality of the cells used in cell therapies, in regenerative medicine and of those used for modelling metabolic processes.
Deskriptorji     LIVER