Apoptosis Induction of Salvia chorassanica Root Extract on Human Cervical Cancer Cell Line

Abstract

Salvia chorassanica Bunge is one of the Iranian endemic species of Salvia. There is not any reported literature on S. chorassanica. This study was designed to examine the in-vitro anti-proliferative and proapoptotic effects of the methanol extract of S. chorassanica and its fractions on HeLa cell line. Cells were cultured in EX-CELL®, an animal free medium specially designed for HeLa cell line and incubated with different concentrations of plant extracts. Cell viability was quantified by MTS assay. Apoptotic cells were determined using propidium iodide (PI) staining of DNA fragmentation by flow cytometry (sub-G1 peak). Activity of caspase -3, -8 and -9 was measured by the caspase colorimetric kit assay. S. chorassanica inhibited the growth of malignant cells and the CH2Cl2 fraction was determined as the most cytotoxic fraction in comparison with other fractions. The calculated IC50 values for methanol extract, n-hexane, CH2Cl2 and EtOAc fractions were 8.841, 5.45, 2.38, and 58.03 µg/mL, respectively. S. chorassanica induced a sub-G1 peak in the flow cytometry histogram of treated cells compared to control cells indicating that the cytotoxic mechanism is characterized by apoptosis induction. The activity of caspase-3 and 8 proteins in treated HeLa cells was significantly higher than that of the control while caspase-9 activity did not change significantly. Based on the result obtained from our study, the apoptosis pathway involved in S. chorassanica-induced cell death may be through the extrinsic pathway and it can be a novel promising candidate in the treatment of cancer.