Human Neural Stem Cell Metabolomic, Cellular and Organ Level Adverse Outcome Pathway Relationships for Endocrine Active CompoundsEPA Grant Number: R835551
Title: Human Neural Stem Cell Metabolomic, Cellular and Organ Level Adverse Outcome Pathway Relationships for Endocrine Active Compounds
Investigators: Stice, Steve , Lu, Kun , Smith, Mary Alice , Zhao, Qun
Institution: University of Georgia
EPA Project Officer: Lasat, Mitch
Project Period: September 1, 2013 through August 31, 2016 (Extended to August 31, 2017)
Project Amount: $799,938
RFA: Development and Use of Adverse Outcome Pathways that Predict Adverse Developmental Neurotoxicity (2012) RFA Text | Recipients Lists
Research Category: Health , Human Health , Safer Chemicals
The overarching objective is to determine endocrine active compounds (EACs) adverse outcome pathway relationships among three windows of susceptibility (WOS) spanning the approximate time of neural tube formation in human development. We will use differentiating neural progenitor (NP) cells in metabolomic, cell function and in vivo chick embryo central nervous system (CNS) assays to reach this goal and provide key elements along the adverse outcome pathway continuum. Obj 1: Characterize metabolomic profiles during neural tube stage WOS using differentiating NP cells exposed to escalating doses of EACs. Obj 2: Associate EAC induced alterations in key human neural cellular events with the metabolic changes. Obj 3: Quantify and link human NP cell WOS changes in a neural cell/chick CNS model to key elements of metabolite and cellular profiles. Our hypothesis is that the broadly selected EACs will generate WOS-specific metabolome signatures that are linked to other key events in the AOP, including cell/organ function and development, in a dose-dependent manner. Additionally, we hypothesize that early WOS will be more susceptible than the late stage WOS.
Utilizing a biomarker-based metabolomics approach, we will expose the NP cells differentiated to represent three associated WOS to known and potentially neural EACs and identify fluxes in the endogenous metabolome using gas chromatography coupled to mass spectrometry, cytotoxicity/apoptosis, neurite outgrowth, cell proliferation and glutamate receptor function. In addition, longitudinal NP cell migration and effects on organ formation in chick embryos will be quantified using MR and fluorescence imaging.
We expect that classes of EACs will generate unique metabolite spectra with differentially up- or down-regulated metabolites for each WOS. However, there will be metabolite signatures that will cut across all EACs within and among WOS. We expect EAC induced perturbations in both metabolism and cellular function assays and strength of linkage will increase with escalating doses. However, unique EAC may differ and linking the metabolism with cell function data is key to providing information on the AOP continuum. Lastly, we expect an inexpensive chick embryo assay will provide higher organ level information on vulnerability of WOS in the intact CNS by monitoring survival, morphology and migration and associate changes with earlier objective results. Understanding the key events within and among WOS provides biomarkers for at risk human populations and further information for predicting adverse outcomes in human neurodevelopment for classes of EAC.