Fig. 2.
Detection of apoptosis induced by atorvastatin on quiescent hepatic stellate cells (HSCs). HSCs at days 2 and 7 of primary culture were incubated for 20 h in serum-reduced (0.3% foetal calf serum) culture medium alone or in the presence of atorvastatin (10−3, 10−5, 10−7, 10−9, 10−11 mol/L). (A) In activated HSCs (day 7), the percentage of cells undergoing apoptosis increased proportionally from a control value of 19% apoptosis (spontaneous apoptosis) with increasing doses of atorvastatin to 60% at physiological serum concentrations (10−7 and 10−8 mol/L) and to 92% apoptosis at a dosage of 10−3 mol/L atorvastatin. (B) The effects of atorvastatin on quiescent HSCs (day 2) was not significant at physiological serum even though at higher concentrations (10−5 and 10−3 mol/L), the fraction of cells in apoptosis increased from a basal level of 4–10%. Data were obtained by fluorescent-activated cell sorting analysis of cells stained with annexin V–fluorescein isothiocyanate and propidium iodide. Values presented are mean percentages of seven independent experiments. Values are means±SD. Level of significance: *P < 0.05; **P < 0.01.