Cytotoxicity of Benzyl Butyl Phthalate and Its Metabolites on Sertoli Cells in Mice

Abstract

Background: Benzyl butyl phthalate (BBP) is an environmental endocrine disruptor, with an estrogen-like effect. To elucidate the toxicity mechanism of BBP on Sertoli cells, BBP and its metabolites monobutyl phthalate (MBuP), phthalic acid (PA), hippuric acid (HA) were selected for simultaneous study. Methods: The effects of BBP and its metabolites on Sertoli cells were observed by cytotoxicity assay (MTT assay) and cell cycle assay. The key proteins in Sertoli cells were detected by Western blot to find out the toxic mechanism of BBP. Results: The MTT assay results showed that BBP (10^–5, 10^–6, 10^–7 mol/L) and HA (10^–6 mol/L) significantly induced cell proliferation, while MBuP (10^–4, 10^–5 mol/L) and PA (10^–4, 10^–5 mol/L) significantly inhibited cell proliferation at 72 h. The results of cell cycle assay showed that both BBP and its metabolites significantly increased the proportion of G2 phase (Anaphase of DNA synthesis). The Western blot assay showed that estradiol (E2) significantly decreased the expression of vimentin and androgen binding protein (ABP), BBP significantly induced the expression of ABP and significantly decreased the expression of vimentin, MBuP and PA significantly reduced vimentin and ABP, HA significantly increased vimentin and ABP. BBP significantly promoted the expression of ABP similar to HA, and destroyed the cytoskeleton structure similar to MBuP and PA. Conclusions: This study revealed that the reproductive toxicity of BBP was directly related to its metabolites.