Hepatocytes culture time, effects

Studies of ibuprofen and other NSAIDs have produced toxic effects at concentrations 10 times therapeutic in cultured hepatocytes. No adverse effect on cell survival was noted at therapeutic concentrations of ibuprofen in this model, although increases in lactate dehydrogenase leakage were prominent. 

Apoptosis can be triggered by mitochondrial damage, which is followed by the release of cytochrome c and the caspase cascade [167], The BAX protein activates mitochondrial release of cytochrome c [168], while Bcl-2 is a mitochondrial protein inhibits the apoptotic process and promotes cell survival [169]. Ji et al. [163] research showed that occur a decrease in mitochondrial Bcl-2 and a markedly increase in mitochondrial level of Bax in the HepG2 cells treated with PA from 200 to 400 mM concentrations. The authors suggest that this mechanism can contribute to NASH and NAFLD installation, and especially may play an important role in the transition from steatosis to steatohepatitis in human. Other studies [170] on the effect of FAs-induced steatosis on cellular apoptosis have demonstrated that palmitic and oleic FA mixtures-induced steatosis is associated with apoptosis in hepatocyte cell cultures. Joshi-Barve s et al. [171] studies also showed that exposure to excess palmitic acid induces apoptosis and lL-8 production in hepatocytes in a relation of dose-dependent and time dependent manner, via activation of c-Jun amino terminal kinase (JNK/AP-1), and nuclear factor kappa B (NF-B) transcription factors for IL-8 expression. 

Fig. 1. Repair-associated fluctuations of the relative amount of free DNA in chromatin effect of poly(ADP-ribose) depletion. Hepatocytes were cultured for 24 hr in the presence or absence of 8 mM 3-aminobenzamide [poly(ADP-ribose) depletion, see text], exposed to 5 (A), 50 (B), or 500 (C) pM AAAF for 20 min and allowed to continue repair in the presence of 3-aminobenzamide at 37°C after removal of the carcinogen. At the times indicated, the portion of free DNA in chromatin was determined using [8-methoxyPH] methoxypsoralen the amount of radioactivity covalently bound to DNA is directly proportional to the relative amount of free DNA in the chromatin of intact cells (2, 4). The results are expressed in percent of the values in untreated control cells. A, 5 hM AAAF B, 50 AAAF C, 500 iM AAAF. O—O, control — , poly(ADP-ribose) depletion (n = 2).

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