In vitro evaluation of cytotoxicity of n-hexane extract from Alnus sieboldiana male flowers on VERO and HEK293 cell lines

Abstract

Introduction and objective. Alnus sieboldiana (Betulaceae) is a warm temperate tree distributed in highland areas along the Pacific shores of central Japan. The aim of the study was to evaluate the cytotoxic activity of fractions obtained from n-hexane extract from male flowers of Alnus sieboldiana towards VERO and HEK293 cell lines. Materials and methods. Cytotoxicity was estimated using the MTT method. The following cell cultures were used: Vero (ECACC No. 84113001) and HEK293 (ATCC No. CRL-1573). Results. The results indicate that purified n-hexane fraction (F1) showed lowest cytotoxicity among tested fractions, both towards VERO and HEK293 cell lines, with EC 50 values of 145 and 154 µg/ml, respectively. The highest cytotoxicity (EC 50 =23, EC 5 =10 µg/ml) was observed for fraction F3 on HEK293 cell line. Fractions F2, F3 and F4 showed higher cytotoxicity on HEK293 than on VERO cell line with EC 50 values of 46, 23, 40 and 73, 44, 48 µg/ml, respectively. Fractions F3 and F4 showed similar toxicity on VERO cell line (EC 50 =44, EC 5 =35 µg/ml and EC 50 =48, EC 5 =31 µg/ml, respectively), whereas F3 was significantly more toxic than F4 on HEK293 cell line (EC 50 =23, EC 5 =10 µg/ml and EC 50 =40, EC 5 =25 µg/ml, respectively). Conclusions. The human HEK293 cell line was more sensitive to tested fractions with the exception of F1. Studies on cytotoxicity of A. sieboldiana flowers on VERO and HEK293 cell lines may prove to be useful in the assessment of non-cytotoxic concentration of fractions that will be used during future research on the biological activity of this plant. EtOAc fraction (F3) showed potent cytotoxic activity, especially on HEK293, and therefore should be further analyzed using appropriate cell lines for potential anticancer properties.