Cytotoxicity of gypsogenic acid isolated from Gypsophila trichotoma

Background: Gypsophila trichotoma Wend. (Caryophyllaceae) is a medicinal plant which is protected in Bulgaria by the Biodiversity Law. Previous studies have showed the presence of triterpene saponins, sterols, flavonoids, triterpens, etc. Objective: Gypsogenic acid, isolated from Gypsophila trichotoma roots, was evaluated for cytotoxic activity. Materials and Methods: The structure of the compound was elucidated by spectral methods. The cell survival fraction was determined by the MTT dye reduction assay, performed with some modifications. Results: Gypsogenic acid was tested in a panel of human tumor cell lines and was found to inhibit the proliferation of malignant cells. It was active against leukemic cells with lymphoid (SKW-3 and BV-173) or myeloid phenotype (HL-60, K-562, and LAMA-84), as well as against the EJ bladder carcinoma cell line. Bcr-Abl expressing myeloid cells (LAMA-84 and especially K-562) displayed lower sensitivity. HL-60/Dox cells were less sensitive to gypsogenic acid than the parent cell line, which shows that gypsogenic acid is probably a substrate of MRP-1.