Antiproliferative and Apoptotic Activities of the Medicinal Plant Ziziphus obtusifolia

BACKGROUND: Ziziphus obtusifolia is a spiny shrub found in Northwest Mexico desert, with traditional medicinal use to treat several diseases including cancer. OBJECTIVE: The aims of the present study were to evaluate the antiproliferative and apoptotic activities of the aerial parts of this plant. MATERIALS AND METHODS: The methanol extract and its fractions were prepared using several solvents. The antiproliferative activity was evaluated by the (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium) (MTT) assay on HeLa, A549, RAW 264.7, M12.C3.F6, and L-929 cell lines, and the apoptotic activity using Annexin V and (5,50,6,60-tetra-chloro-1,10,3,30-tetra-ethylbenzimidazol-carbocyanine iodide) staining. The most active fraction was further separated by column chromatography. RESULTS: The most active fraction was hexane with an IC(50) of 90.4 μg/mL against RAW 264.7, 94 μg/mL against M12.C3.F6, 165.5 μg/mL against HeLa and 187.7 μg/mL against A549 cell lines. In apoptotic activity assays the methanol extract and its n-hexane fraction were found to induce mitochondrial depolarization in HeLa cells (83 and 87% respectively), and both induced the externalization of the phosphatidylserine increasing the percentage of cells in early apoptosis from 1.4% in untreated control cells, to 1.9% and 3.5% for methanol extract and n-hexane fraction-treated cells, respectively, statistically different for the total percentage of apoptotic cells (P < 0.05). CONCLUSIONS: These results show that Z. obtusifolia has antiproliferative and apoptotic activities in vitro and confirms its use in traditional medicine. SUMMARY: The methanol extract and its fractions using several solvents were evaluated in the antiproliferative activity by the MTT assay on HeLa, A549, RAW 264.7, M12.C3.F6, and L-929 cell lines, and the apoptotic activity using Annexin V and (5,50,6,60-tetra-chloro-1,10,3,30-tetra-ethylbenzimidazol-carbocyanine iodide) staining. The most active fraction against cell lines was hexane. In apoptotic activity assays, the methanol extract and its n-hexane fraction were found to induce mitochondrial depolarization. This results we showed that Ziziphus obtusifolia has antiproliferative and apoptotic activities in vitro. [Image: see text] Abbreviations Used: DMEM: Dulbecco's modified eagle's medium, DMSO: Dimethyl sulfoxide, MTT: (3-4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium), JC-1: (5,50,6,60-tetra-chloro-1,10,3,30-tetra-ethylbenzimidazol-carbocyanine iodide), FBS: Fetal bovine serum, CAPE: Caffeic acid phenethyl ester, PBS: Phosphate-buffered saline.