Clastogenic, aneugenic and cytostatic effects of Smallanthus sonchifolius leaf extract in a human tumoral cell line

Smallanthus sonchifolius leaf extracts show potential health benefits but also exhibit cytotoxicity in vitro. This study evaluated the genotoxic effects of a crude extract rich in sesquiterpene lactones (CLM) in HeLa cells. HPLC/MS-MS analysis identified smallanthin, polymatin B, uvedalin, and enhydrin as major components. MTT assay determined the effective concentration range, and the cell cycle analysis was performed using flow cytometry. Genotoxic mechanisms were examined by chromosome aberration analysis and the cytochalasin B-blocked micronucleus with γ-H2AX detection test. The CLM extract induced cytotoxicity, arrested the cell cycle at the G2/M phases and decreased Mitotic and Nuclear Division Indices, and triggered DNA double-strand breaks in DNA and led to chromosome missegregation. Our findings indicate that CLM exerts clastogenic and aneugenic effects, leading to G2 phase arrest for DNA repair. Due to their genotoxicity, STLs show promise as potential candidates for developing new cancer therapeutics.