RESUMO
Objective To study the mechanism of tumor necrosis factor-related apoptosis-inducing ligand(TRAIL)-induced apoptosis of glioma U87 cells.Methods Human glioma U87 cells were treated with human recombinant soluble TRAIL(rsTRAIL),and the cell apoptosis was detecmd with flow cytometry with AnnexinV-FITC/PI double staining.Flow cytometry with DiOC6 staining was used to assess the changes in mitochondrial transmembrane potential(△ψm).The relative activity of caspase-3,-8 and-9 Was measmed by colorimetric assay,and the concentration of cytoplasmic cytochrome C(cyt C) determined using enzyme-linked immunosorbem assay.The effects ofcaspase-8 inhibitor(Z-IETD-fmk)on rsTRAIL-induced apoptosis,△ψm,caspase-3,-8 and-9 activities and cyt C concentration were observed. Results RsTRAIL tinle-dependently induced apoptosis and progressive collapse of △ψm in glioma U87 cells,resulting also in caspase-3,-8 and-9activation and elevated cytC concentration.Caspase-8 inhibitor partially antagonized these biological effects induced by rsTRAIL in U87 cells.Conclusion TRAIL initiates a cascade of mitochondrial events by activating caspase-8 and induces apoptosis of glioma U87 cells.
RESUMO
The two title chromene compounds, 3,3a-dihydrocyclopenta[b]chromen-1(2H)-one, C16H12O2, (I), and 2-(2-hydroxybenzylidene)-3,3a-dihydrocyclopenta[b]chromen-1(2H)-one, C19H14O3, (II), have been determined in the monoclinic space group P2(1)/n. Compound (I) is mainly stabilized by C-H...pi interactions. Compound (II) is linked into infinite one-dimensional chains with a C(3) motif via intermolecular O-H...O hydrogen bonds. The intermolecular C-H...pi and pi-pi interactions also play key roles in stabilizing the crystal packing. Two intramolecular C-H...O hydrogen bonds with S(5) motifs were detected in (II).