The Cytotoxic Effect of Oshá on Human Breast Cancer Cells, Normal Human Blood Cells, and Embryonic Mouse Cells

Oshá or oshála is the traditional name of plants in the genera Lomatium and Ligusticum that are used medicinally by indigenous peoples in North and Central America. Oshá root has been used medicinally in women’s medicine as a natural contraceptive, an abortifacient, an emmenagogue, and an oxytocic agent. Given its traditional use in women’s medicine, previous researchers hypothesized that it would have an effect on estrogen receptor positive breast cancer cells. In a previous study in this laboratory, ethanolic extracts of certain oshá root extracts showed cytotoxic effects on the breast cancer cell lines MCF-7, BT-474, and MDA-MB-231. Aqueous extracts had no cytotoxic effect on any of the assayed cell lines. The current study investigated the effects these same extracts have on normal human peripheral blood mononuclear cells (PBMC) and mouse embryonic cells (3T3). This study produced the EC50 values of 80 ± 3, >100, and >100 mg/ml for Ligusticum porteri, Ligusticum grayi, and Lomatium californicum extracts, respectively, on PBMC, and 40 ± 1 and 55 ± 1 mg/ml for L. grayi and L. californicum extracts, respectively, on 3T3. These findings indicate that the traditional use of oshá as an abortifacient may be due to its cytotoxicity towards embryonic cells. Further investigation of these extracts and their cytotoxic effects on other types of cells is warranted.