In vitro cytotoxicity and genotoxicity screening of Cuscuta arvensis Beyr. and Achillea wilhelmsii C. Koch in preclinical analysis for further drug design

Plant-based compounds have been used for medicinal purposes since ancient times, as easily accessible and low-cost treatment options. Despite the widespread belief that plants are quite safe and devoid of side effects, scientific studies have revealed the toxicity potential of active components of plants on healthy cells. The present study was designed to investigate in vitro cytotoxicity and genotoxicity potential of Achillea wilhelmsii C. Koch and Cuscuta arvensis Beyr., which are frequently used in traditional medicine. In this context, cytotoxicity evaluation of the extracts was performed by MTT (3- [4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide) assay. Our cytotoxicity results indicated that the extract from A. wilhelmsii did not affect the viability of fibroblasts at any of the concentrations, but rather significantly stimulated cell proliferation from a concentration of 25 µg/mL. On the other hand, the extract from C. arvensis significantly reduced the viability of fibroblasts at all concentrations tested. In the second part of this research, the DNA damaging potential of the extracts was investigated by in vitro comet assay at non-cytotoxic concentrations. A. wilhelmsii extract caused a significant increase in the percentage of DNA in the tail (%TDNA), which is considered an indicator of DNA damage, only at the highest concentration, while C. arvensis extract did not significantly affect %TDNA at concentrations tested. The results of the present study indicated that the methanolic extract from A. wilhelmsii may be considered safe up to a concentration of 100 μg/mL, however, the cytotoxicity potential of C. arvensis may be a factor limiting its safe use.