An evaluation of the anti-proliferative and pro-apoptotic properties of Nigella Sativa

Background: Nigella sativa is a traditional herb used since ancient Egyptian and Greek civilizations. It is also known as black seed, black cumin, and as the blessed seed, after its reported extraordinary curing ability. Nigella sativa has a broad range of therapeutic properties including anti-cancer, anti-oxidant, anti-inflammatory, anti-microbial, anti-helminthic, and anti-fungal activities. Objective: The aim of this study was to evaluate the anti-cancer properties of Nigella sativa oil on the Jurkat E6.1 cell line. Method: Investigation of the anti-cancer properties of Nigella sativa oil in the human T lymphoblastic Jurkat E6.1 cell line was undertaken evaluating 4 different concentrations (undiluted, diluted 1:10,1:50 and 1:100) at three time points (24, 48 and 72 hours). Cell viability was assessed using the vital dye, trypan blue. Apoptosis was detected using the Human Annexin V assay by flow cytometry. Wilcoxon Signed–Rank test was used for statistical analysis. A p-value ≼ 0.05 was considered statistically significant. Results: Cells treated with undiluted oil could not be assessed by trypan blue due to the hydrophobicity of oil and bubble formation when mixed with culture media. The 1:10 dilution had the highest percentage of non-viable cells with 92.78% followed by 90.53% and 67.62% for the 1:50 and 1:100 dilutions, respectively, after 72 hours. Cells treated with undiluted oil had 58.18% apoptotic cells followed by 44.3%, 33.89% and 26.81% for the 1:10, 1:50 and 1:100 dilutions respectively. Conclusion: Nigella sativa seed oil induced apoptosis and inhibited cell proliferation in the Jurkat E6.1 cell line in vitro in a time- and dosage-dependant manner. Further research is required to determine whether Nigella sativa demonstrates similar efficacy in other leukaemic cell lines, and other cancer types, and also to determine which bioactive constituent(s) present is(are) responsible