Figure 3.
Distinct apoptotic pathways in 16HBE14o- cells after CB and TiO2 NP exposure: role of mitochondrial pathway. A) Loss of mitochondrial membrane potential. A time course study (0.5 -- 4 hours) after exposure to CB and TiO2 NPs (20 μg.cm-2). At the end of incubation cells were labeled with CMXRos fluorochromes (150 nM) for 20 minutes and % of CMXRos negative cells was determined by flow cytometry. Data are represented as mean ± SD (n = 3). Representative results of at least three independent experiments. * statistically different from control p < 0.05 (two tailed). C) Immunofluorescent detection of apoptotic proteins involved in mitochondrial pathway in 16HBE 14o- cells after 4 hours of NP exposure (20 μg.cm-2). Representative images of a cell undergoing apoptosis after treatment with CB and TiO2 NPs. Cells were stained with monoclonal antibodies against B) activated bax (6A7) C) cytochrome c (C-20). Nuclei were counterstained with Hoechst 33342. (×1000)