Experimental studies on male reproductive toxicity of bisphenol A in vitro and vivo / 中华预防医学杂志

<p><b>OBJECTIVE</b>To explore the effects of Bisphenol A in adult rats and its possible mechanisms.</p><p><b>METHODS</b>BPA (in corn oil) was administered orally to 9-week-old male Sprague-Dawley rats for 14 days (0, 1 and 5 g/kg bw), and incubated primary Sertoli cells from pubertal SD rats with 0, 10(-7), 10(-6), 10(-5), 10(-4) mol/L BPA.</p><p><b>RESULTS</b>After oral administration, a significant decrease in right testis weight was observed in 5 g/kg dose group, but not in the 1 g/kg bw dose group. Germ cells were detached from basement membrane of seminiferous tubules and Sertoli cells in BPA-treated groups. Administration of BPA at 1 g/kg bw and 5 g/kg bw produced both nucleus pycnosis and vacuolized nucleus in germ cells and Sertoli cells. A marked loss in vimentin staining in Sertoli cells from testis of BPA-treated rats was detected. No change in levels of serum estradiol and testosterone was observed after two-week exposure to BPA. In Sertoli cell primary culture, BPA destroyed the cytoskeleton and cell-cell junctions, and elongated Sertoli cells.</p><p><b>CONCLUSION</b>These results suggest that BPA may injure reproductive function of male rats by destroying the cytoskeleton and changing the form of Sertoli cells.</p>

The effects of three plastic additives on the proliferation of MCF-7 cell / 中华预防医学杂志

<p><b>OBJECTIVE</b>To explore the effect of environmental estrogens on the proliferation of breast cancer cell line MCF-7.</p><p><b>METHODS</b>The tested compounds were n-4-nonyphenol, Bisphenol A and dibutylphthalate. Human estradiol-dependent MCF-7 breast cancer cells were grown in DMEM medium containing 10% bovine serum. Five days before the addition of the test compounds, the cells were washed by phosphate-buffered saline, and the medium was substituted with a phenol red-free DMEM medium containing 5% dextral charcoal-stripped FBS. The respective test compound was added in fresh medium and the control cell received only the vehicle (ethanol). The proliferation of MCF-7 was analyzed by the MTT assay, (3)H-TdR incorporation assay and flow cytometry.</p><p><b>RESULTS</b>Compared with the ethanol control, the proliferation and DNA synthesis of the test cells treated with n-4-nonyphenol (8 x 10(-7) mol/L, 96 h), Bisphenol A (8 x 10(-7) mol/L, 96 h) or dibutylphthalate (32 x 10(-6) mol/L, 96 h) treatment was markedly enhanced in a time-dependent and dose-dependent manner.</p><p><b>CONCLUSION</b>n-4-Nonyphenol, Bisphenol A and dibutylphthalate enhanced the proliferation of human breast cancer cell in vitro, which may demonstrate an estrogenic activity.</p>