Proteins Expression Of Beta- Catenin, DDK-1 In Bisphenol A Exposure Before And After Birth On Male Rat Reproductive Cells

Background Bisphenol A(BPA) is a kind of phenolic environmental estrogens which often appears in our daily lives. It has corresponding biological toxicity by interfering the body’s own hormone synthesis and secretion. Previous studies have shown that BPA has toxicity to the testis, and is potential endocrine disruptors. BPA affected the body normal state through a variety of signaling pathways, meanwhile the Wnt/β-catenin signaling pathway is a key signaling pathways to regulate the body growth and development. There were a lot of experiments showed that the Wnt/β-catenin signaling pathway played a key role in the tumour, hematopoietic stem cells, neural precursor cells and cell proliferation and other fields, but this was a rare in the field of reproduction toxicity.Objective To explore the proteins expression and significance of β-catenin, DKK-1 in bisphenol A(BPA) exposure before and after birth on male rat reproductive.Methods Pregnant ICR mice were randomly divided into 4 groups(1 solvent control and 3 treatment groups). There were 9 mice in each group. The mice in BPA groups were administered with BPA(10, 50, 300nmol/L) by drinking water from gestational day 0 to weaning on postnatal day(PND) 42. Then counted the number of offspring which each pregnant mouse produced and countmale/female ratio of offspring in each group. On postnatal day(PND) 42, male offspring were sacrificed. Removed sterile bilateral testicular rats and weighed. 4% paraformaldehyde was used for fixation. H.E staining was used for detecting pathological changes of the testicular tissue. Immunohistochemical was used to detect testicular tissue of the expression of β-catenin and DDK-1. Western blot was used to detect testicular tissue of β-catenin and DDK-1 expression levels.Results There was no significant difference between offspring of the control groups and the treatment groups in the number of offspring and male-female proportion(P>0.05), and the testicular viscera coefficient in BPA groups decreased(P<0.01) with increasing dose of BPA. Compared with offspring of the control groups, the treatment groups were found that the number and plies of spermatogonia cells decreased and this cells disordered arrangement. However, Immunohistochemistry and Western blot results showed that the expressions of β-catenin and DDK-1 significantly up-regulated in the middle and high dose group. Meanwhile, β-catenin and DDK-1 expressed mainly in spermatocyte and Leydig cells.Conclusion Exposure to BPA before and after birth has some toxic effects on the testis of male ICR offspring. The mouse testis coefficient decline, spermatogenic cells and Leydig cells morphological changes, which result from activating the Wnt/β-catenin signaling pathway.