Project Summary/Abstract
Recent research has demonstrated that factors generally associated with obesity such as activity level,
genetics, and diet, are insufficient to account for the magnitude and speed of the worsening obesity epidemic.
Increasing research to evaluate other causative factors has focused on environmental contaminants that have
been demonstrated to impact metabolic health. Many chemicals have been demonstrated to promote
adipocyte commitment from multipotent precursors or promote triglyceride accumulation and/or pre-adipocyte
proliferation in vitro, while some have been further demonstrated to directly increase weight gain and/or
metabolic dysfunction in vivo. Alkylphenol and alcohol polyethoxylated surfactants are found at high levels in
unconventional oil and gas wastewater, indoor house dust extracts, and wastewater effluent, and have been
recently demonstrated to promote potent and efficacious lipid accumulation and pre-adipocyte proliferation in
the 3T3-L1 mouse pre-adipocyte cell model. Interestingly, they appear to exert this activity through a
mechanism other than peroxisome proliferator-activated receptor-gamma (PPAR¿), often considered the
master regulator of fat cell development. This proposal aims to interrogate the potential for in vivo metabolic
disruption by these ubiquitous environmental contaminants through a mentored training aim (K99 phase). This
aim will provide crucial experience utilizing zebrafish as a model organism to bridge in vitro and mammalian in
vivo research, gaining skills in targeted molecular interrogation techniques, and culminating in a mentored
exposure experiment assessing the impact of select alkylphenol and alcohol polyethoxylates on metabolic
health of zebrafish. The independent aims of this fellowship (R00 phase) include a comparison of metabolic
mechanism interrogation, comparing zebrafish and human receptor pathways utilizing in vitro model systems
to elucidate mechanisms through which these contaminants might affect human health and how these may
differ from those of a common endocrine in vivo model. Further, this fellowship will use technology applied in
the previous NRSA fellowship, utilizing modified, non-immobilized receptor ligand binding domains and high
resolution mass spectrometry of complex environmental samples known to contain alkylphenol and alcohol
polyethoxylates: hydraulic fracturing wastewater, indoor house dust, and wastewater effluent. We will
quantitate polyethoxylates and determine their relative contribution to the adipogenic activity induced by these
environmental mixtures to assess their relative influence on environmental metabolic disruption. These skills
will prove critical to my career goals of becoming an independent health-science researcher in an academic
setting by establishing a comprehensive pipeline from in vitro testing of emerging contaminants and mixtures to
assessing putative impacts on human health. Coupled with skills with high resolution mass spectrometry
gained under the NRSA fellowship, I will be uniquely placed to assess and characterize complex environmental
mixtures of contaminants and emerging contaminants from in vitro to robust in vivo models.