Purpose: To investigate the anti-cancer effect of methyl alcohol extract of Enteromorpha linza (Linnaeus) J. Agardh (MEEL) in U937 human leukemia cells. Methods: Cytotoxicity was evaluated by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay. Apoptosis was detected using 4′,6-diamidino-2-phenylindole (DAPI) staining, agarose gel electrophoresis, and flow cytometry. Protein levels were determined by Western blot analysis. Caspase activity was measured spectrophotometrically at 405 nm. Results: MEEL inhibited U937 cell proliferation and induced apoptosis through up-regulation of death receptor-related gene expression, caspase-8 activation and truncation of Bid, which was associated with the loss of mitochondrial membrane potential. Subsequently, the levels of anti-apoptotic proteins such as Bcl-2 and Bcl-xL, and IAP family proteins decreased but those of pro-apoptotic proteins including Bax and Bad increased in MEEL-treated U937 cells. MEEL treatment also resulted in activation of caspase-9 and-3 as well as concomitant cleavage of poly(ADP-ribose) polymerase and phopholipase Cγ-1. However, pretreatment of U937 cells with z-VAD-fmk, a pan caspase inhibitor, abrogated chromatin condensation and DNA fragmentation and prevented cell death induced by the MEEL. Conclusion: The findings suggest that MEEL induced apoptosis in U937 cells through a signaling cascade of death-receptor-mediated extrinsic as well as mitochondria-mediated intrinsic pathways, thus raising the possibility that MEEL may be of value in the development of novel therapeutic approaches for treating leukemia. © Pharmacotherapy Group, Faculty of Pharmacy, University of Benin, Benin City, 300001 Nigeria. All rights reserved.
CITATION STYLE
Choi, E. O., Kim, H. S., Han, M. H., Park, C., Kim, B. W., Hwang, J. A., … Hwang, H. J. (2014). Induction of apoptosis by methyl alcohol extract of Enteromorpha linza (linnaeus) J Agardh in U937 human leukemia cells. Tropical Journal of Pharmaceutical Research, 13(6), 881–888. https://doi.org/10.4314/tjpr.v13i6.8
Mendeley helps you to discover research relevant for your work.