Figure 7
From: Cellular and molecular mechanisms of cigarette smoke-induced lung damage and prevention by vitamin C
AECS/p-BSQ/p-BQ-induced apoptosis in A549 lung epithelial cells ex vivo . A, Detection of DNA strand break using TUNEL assay. The cells were examined using a fluorescence microscope (Olympus B, magnification × 20). Digital images were captured with cool CCD camera (Olympus). Upper panel, TUNEL positive cells; lower panel, nuclei stained with DAPI. About 10 fields (150 cells/field) of three independent experiments were evaluated. A549 cells (2 × 106) were treated with 50 μl of AECS, 180 nmoles p-BSQ or 90 nmoles p-BQ in culture medium at 37°C for 24 h. B, Quantitative evaluation of TUNEL positive cells treated with AECS/p-BSQ/p-BQ; PBS indicates control treated with phosphate buffered saline; small bars over the columns indicate ± SD. C, Activation of pro-caspase-3 analyzed by immunoblotting. D, Cleavage of poly ADP ribose polymerase (PARP) analysed by immunobloting using anti PARP antibody. For immunoblot assay of caspase 3 and PARP, cells were treated with AECS, p-BSQ or p-BQ for 12 h. Similar observations were made in three independent experiments.