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Developmental Effects Of Chronic Low-Level Arsenic Exposure In Mouse Embryonic Stem Cells And In Human Induced Pluripotent Stem Cells, M. Chiara Perego

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Arsenic is an environmental contaminant commonly found in food and drinking water. Exposure to arsenic during embryonic development has been linked to reduced muscle growth, disrupted muscle development and locomotor activity, impaired neurodevelopment, reduced IQ, impaired memory and learning deficits. While the mechanisms responsible for developmental changes following in utero exposure to arsenic are not well known, one possibility is that arsenic might disrupt proper cellular differentiation. Therefore, we aimed to investigate the mechanisms by which arsenic exposure could alter stem cell differentiation into neurons.

First, we continuously exposed P19 mouse embryonic stem (ES) cells to 0.1 μM (7.5 ppb) …

Arsenic Inhibits P19 Stem Cell Differentiation By Altering Microrna Expression And Repressing The Sonic Hedgehog Signaling Pathway, Jui Tung Liu

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Arsenic is a naturally-occurring toxicant that exists in bedrock and can be leached into ground water. Humans can be exposed to arsenic via contaminated drinking water, fruit, rice or crops. Epidemiological studies have shown that arsenic is a developmental toxicant, and in utero exposure reduces IQ scores, verbal learning ability, decreases long term memory, and increases the likelihood of dying from a neurological disorder. Arsenic can also reduce birth weight, weight gain, and muscle function after an in utero exposure. Although the mechanism behind these physiological changes is not known, in vitro studies have shown that arsenic can reduce muscle …

Arsenic Targets Neural Plate Border Specifier Cells In P19 Cells, Christopher Mccoy

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Epidemiological studies have shown that arsenic exposure during early embryogenesis can cause reduced weight gain and neurological deficits later on in life. In addition, in vitro and in vivo studies have indicated that arsenic suppresses neurogenesis and myogenesis. The exact mechanism of how arsenic causes these undesired developmental outcomes is poorly understood, however both skeletal muscle and sensory neuron development require the Wnt/β-catenin signaling pathway to initiate the specific differentiation of precursor cells. We were interested in determining the target cell population of arsenic and its metabolites. Arsenic's metabolites were of interest because they have been shown to be more …

Arsenic Affects Muscle Development And Structure In Fundulus Heteroclitus, Angela D'Amico

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Arsenic is a naturally occurring metalloid that can enter rivers and ground water. Epidemiological studies have correlated arsenic exposure with adverse developmental outcomes such as low birth weight, delays in the use of musculature, and altered locomotor activity. Previously in our lab, embryonically exposed killifish (Fundulus heteroclitus) were found to have changes in muscle development. Microarray analysis showed several genes involved in muscle development and formation altered and histological analysis showed an increase in small muscle fiber size. In this study, killifish were used to help understand if changes in muscle formation and fiber density after embryonic exposure persist, are …