Effect of Allium sativum (garlic) methanol extract on viability and apoptosis of human leukemic cell lines

Purpose: To investigate the effect of Allium sativum (garlic) methanol extract on viability and apoptosis of human leukemic cells. Methods: Cell viability was determined using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay at concentrations of 3.125, 6.25, 12.5, 25, 50, 100, 200, 400 and 800 ug/mL of Allium sativum extract following 48-h treatment on U-937, Jurkat Clone E6-1 and K-562 cell lines. The mode of cell death was determined by Annexin V-FITC staining and analyzed by flow cytometry. Results: The results show that the half-maximal inhibitory concentration (IC50) of A. sativum on U-937, Jurkat Clone E6-1, K-562 cell lines was 105 ± 2.21, 489 ± 4.51 and 455 ± 3.13 μg/mL, respectively, compared with negative control, while apoptosis was 17.93 ± 0.95 % for U-937 cells (p ≤ 0.05), 38.37 ± 1.88 % for Jurkat Clone E6-1 cells (p ≤ 0.001) and 16.37 ± 1.10 % for K-562 cells. A majority of the cells were inhibited by the extract via apoptosis. Only U-937 cells (6.87 ± 0.65 %) showed significant necrosis compared to negative control (p ≤ 0.05). Conclusion: K-562 cells are the most resistant against garlic extract, in contrast to Jurkat Clone E6-1 cells. Garlic extract does not induce necrosis in Jurkat Clone E6-1 and K-562 cells.