Bisphenol A On The The Development Of Human Embryoid Body: Preliminary Genomics Research

Background: There are large number of studies using the characteristics ofembryonic stem cells (ES) in vitro to understanding the cytotoxicity, inhibition ofdifferentiation and gene expression on embryonic development and regulation, whichshowing the good application propects. When ES colonies were floating cultured in alow-adherence dish, HESCs aggregate to form embryoid bodies(EB) which wascomprising endoderm, mesoderm and ectoderm cell layers. Therefore, EB formationis considered to mimic embryo development during the stages of pre-gastrulation andearly gastrulation. And due to it’s easy to perform various operations processing, EBis the best experimental model to study of early embryonic development andregulation of genetic、 epigenetic germ layers mutual induction、 organ cavityformation and the impact of environmental factors on early embryonic developmentissues.Bisphenol A(BPA), as an important industrial raw materials widely used in theproduction of plastic. Recent studies have confirmed that BPA may be similar inpotency to estradiol in stimulating estrogen receptor in mammal. BPA was commonlyused in food packaging materials so the risk or potential risk on the human healtheshould be draw the public and the government attention, also shoud be the continuous research focus in recent20years. The current reference safe intake dose of bisphenolA was50μg/kg bw/day.However, in recent years some animal experiments show thateven lower than the safe intake dose, the effects of BPA still exists. BPA on the earlydevelopment of human embryos, genetic and epigenetic, and its relationship with thetire-borne diseases are increasingly of concern.In this subject, we establish human embryoid bodies culture system in ourlaboratory.we use EB model and the application of genomics technologies topreliminary study on the impact of bisphenol A on early embryonic development.Objective:1. the establishment of human embryonic stem cell embryoid body cultureplatform for the study of environmental endocrine disruptors on human early embryodevelopment.2. bisphenol A role in the genome of human embryonic stem cellembryoid body system expression spectrum and the embryo Fetotoxic managementmechanism.Methods: Human ES cells were grown in suspension without feeder cells andinhibiting factor bFGF to induce their differentiation into embryoid bodies (EB).Afterthe EB dealt with10-6mol BPA in7days, a genechip was utilized to analyze its genes.We used the same way to deal with the EB in order to get more sample.UsingRealtime PCR, to verify Some of the differentially expressed genes.Results：Compare with the control group which dealt with DMSO in7days, therewere128genes upregulated and431down-regulated with a threshold fold changeover2.0. Analysis these differentially expressed genes with MAS, a software aboutBio-molecular functional annotation system. The results suggested that they wereinvolved in cell differentiation,molecular functions, germinal layer development andsignaling pathways. EB was a powerful tool for learnig human early embryonicdevelopment. Treat the EB with BPA should help us to understand the impact of BPAon early embryonic development and its possible mechanism of action. Conclusion:1. We had established the human embryoid body culture platform and theIdentification of EB technology platform according to the references.2. When EScolonies were floating cultured, it can differentiation of various cell types includingendoderm, mesoderm and ectoderm named EB, which was a useful tool for study theearly human embryonic development and its regulation.3. It was a exploratoryresearch, we try to understand the change of global gene expressions of humanEmbryoid Bodies diposed by Bisphenol A. There were128upregulated genes and431downregulated genes in EB affected by BPA, which including cell differentiation,molecular function, mesoderm development and signaling pathways. Such as PTNand FABP7related with nervous system development.4. As part of a series research,our preliminary study laid the foundation for the group in future to take more samples,increasing experimental verification genes, design more appropriate concentrationand processing time of BPA then got more information from the early embryonicdevelopmental epigenetics affeted by BPA.