AIM: To observe the effect of solanine on the membrane potential of mitochondria in HepG2 cells and [Ca^2+]i in the cells, and to uncover the mechanism by which solanine induces apoptosis.METHODS: HepG2 cells were ...AIM: To observe the effect of solanine on the membrane potential of mitochondria in HepG2 cells and [Ca^2+]i in the cells, and to uncover the mechanism by which solanine induces apoptosis.METHODS: HepG2 cells were double stained with AO/EB, and morphological changes of the cells were observed using laser confocal scanning microscopy (LCSM). HepG2 cells were stained with TMRE, and change in the membrane potential of mitochondria in the cells were observed using LCSM. HepG2 cells were double stained with Fluo-3/AM, and change of [Ca^2+]i in the cells were observed using LCSM. HepG2 cells were double stained with TMRE and Fluo-3/AM, and both the change in membrane potential of mitochondria and that of [Ca^2+]i in the cells were observed using LCSM.RESULTS: Cells in treated groups showed typical signs of apoptosis. Staining with TMRE showed that solanine could lower membrane potential; staining with Fluo-3/AM showed that solanine could increase the concentration of Ca^2+ in tumor cells; and those of double staining with TMRE and Fluo-3/AM showed that solanine could increase the concentration of Ca^2+ in the cells at the same time as it lowered the membrane potential of mitochondria.CONCLUSION: Solanine opens up the PT channels in the membrane by lowering the membrane potential, leading to Ca^2+ being transported down its concentration gradient, which in turn leads to the rise of the concentration of Ca^2+ in the cell, turning on the mechanism for apoptosis.展开更多
基金Supported by the National Natural Science Foundation of China, No. 30400591 the Heilongjiang Province Natural Science Foundation, No. D2004-13, D200505 Harbin City Young Scientist Foundation, No. 2004AFQXJ035
文摘AIM: To observe the effect of solanine on the membrane potential of mitochondria in HepG2 cells and [Ca^2+]i in the cells, and to uncover the mechanism by which solanine induces apoptosis.METHODS: HepG2 cells were double stained with AO/EB, and morphological changes of the cells were observed using laser confocal scanning microscopy (LCSM). HepG2 cells were stained with TMRE, and change in the membrane potential of mitochondria in the cells were observed using LCSM. HepG2 cells were double stained with Fluo-3/AM, and change of [Ca^2+]i in the cells were observed using LCSM. HepG2 cells were double stained with TMRE and Fluo-3/AM, and both the change in membrane potential of mitochondria and that of [Ca^2+]i in the cells were observed using LCSM.RESULTS: Cells in treated groups showed typical signs of apoptosis. Staining with TMRE showed that solanine could lower membrane potential; staining with Fluo-3/AM showed that solanine could increase the concentration of Ca^2+ in tumor cells; and those of double staining with TMRE and Fluo-3/AM showed that solanine could increase the concentration of Ca^2+ in the cells at the same time as it lowered the membrane potential of mitochondria.CONCLUSION: Solanine opens up the PT channels in the membrane by lowering the membrane potential, leading to Ca^2+ being transported down its concentration gradient, which in turn leads to the rise of the concentration of Ca^2+ in the cell, turning on the mechanism for apoptosis.