Abstract: Objective: To investigate whether administering of benzo(a)pyrene (BaP) and schisandrin B (Sch B) to human trophoblast HTR-8/SVneo cells has cytotoxicity and cytoprotection, respectively. Methods: By HTR-8/SVneo cells culture in vitro, MTS cell proliferation assay was performed to detect the effect of different concentration of BaP-alone, Sch B-alone and Sch B combining with BaP treatment on cell proliferation. Results: 0.01 and 0.1 μmol/L BaP did not inhibit HTR-8/SVneo cell proliferation (P＞0.05), but 1, 10 and 100 μmol/L BaP all inhibited HTR-8/SVneo cell proliferation (P＜0.05). The inhibition rate were presented to be escalated accompanied by escalating BaP time exposure (6, 12, 24, 36 and 48 h), and 24 h BaP exposure were presented to be a saturation, especially for 20 μmol/L BaP with 24 h exposure which presented a suitable inhibition rate (24.95%). Besides, 0.01, 0.1 and 1 μmol/L Sch B did not inhibit HTR-8/SVneo cell proliferation (P＞0.05), but the level of SchB higher than 10 μmol/L inhibited HTR-8/SVneo cell proliferation (P＜0.05). 0.25, 0.5, 1 and 2 μmol/L Sch B all attenuated the cytotoxicity induced by BaP in HTR-8/SVneo cells with a dose-effect relationship, especially for 2 μmol/L Sch B which presented a highest protection rate (17.84%). Conclusions: BaP can directly induce cytotoxicity in HTR-8/SVneo cells, while certain Sch B can attenuate the cytotoxicity.

Key words: Benzo(a)pyrene, Schizandrin, Schizandrin B, Trophoblast, Trophoblast cell, Colorimetry