Effects of Methylmercury exposure in 3T3-L1 Adipocytes

Theresa Vertigan; Kriya Dunlap; Arleigh Reynolds; Lawrence Duffy; Theresa Vertigan; Kriya Dunlap; Arleigh Reynolds; Lawrence Duffy

doi:10.3934/environsci.2017.1.94

AIMS Environmental Science

2017, Volume 4, Issue 1: 94-111. doi: 10.3934/environsci.2017.1.94

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Effects of Methylmercury exposure in 3T3-L1 Adipocytes

1.
Department of Chemistry and Biochemistry, University of Alaska Fairbanks, PO box 6160, Fairbanks, AK 99775, USA
2.
Department of Veterinary Medicine, University of Alaska Fairbanks, PO box 7750, Fairbanks, AK 99775, USA

Received: 17 October 2016 Accepted: 03 February 2017 Published: 08 February 2017

Mercury-containing compounds are environmental pollutants that have become increasingly consequential in the Arctic regions of North America due to processes of climate change increasing their release and availability at northern latitudes. Currently, the form of mercury known to be most detrimental to human health is methylmercury, CH3Hg+, which is found in the environment and accumulates in the tissues of piscivores, including those consumed by Alaska Natives through subsistence gathering. Much is known about the neurotoxicity of methylmercury after exposure to high concentrations, but little is known about toxicity to other tissues and cell types, particularly for long-term exposure and the lower concentrations that would occur through fish consumption. Effects of methylmercury exposure on 3T3-L1 adipocytes in culture were assessed using assays for cytotoxicity and an ELISA assay for vascular endothelial growth factor (VEGF), a signaling molecule shown to be important for maintaining metabolic status in adipose tissue. Results showed that exposure to methylmercury leads to significant toxicity in adipocytes at exposures of 100 ng/mL during later stages of differentiation, but lower methylmercury concentrations produced little to no toxicity. Results also showed that VEGF secretion is elevated in adipocytes exposed to methylmercury after the process of differentiating into mature, fat-storing cells. These results provide a basis for further exploration into metabolic consequences of methylmercury exposure on specific cell types and cell models.
- Methylmercury,
- 3T3 cells,
- cytotoxicity,
- VEGF,
- diabetes
Citation: Theresa Vertigan, Kriya Dunlap, Arleigh Reynolds, Lawrence Duffy. Effects of Methylmercury exposure in 3T3-L1 Adipocytes[J]. AIMS Environmental Science, 2017, 4(1): 94-111. doi: 10.3934/environsci.2017.1.94

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Abstract

Mercury-containing compounds are environmental pollutants that have become increasingly consequential in the Arctic regions of North America due to processes of climate change increasing their release and availability at northern latitudes. Currently, the form of mercury known to be most detrimental to human health is methylmercury, CH3Hg+, which is found in the environment and accumulates in the tissues of piscivores, including those consumed by Alaska Natives through subsistence gathering. Much is known about the neurotoxicity of methylmercury after exposure to high concentrations, but little is known about toxicity to other tissues and cell types, particularly for long-term exposure and the lower concentrations that would occur through fish consumption. Effects of methylmercury exposure on 3T3-L1 adipocytes in culture were assessed using assays for cytotoxicity and an ELISA assay for vascular endothelial growth factor (VEGF), a signaling molecule shown to be important for maintaining metabolic status in adipose tissue. Results showed that exposure to methylmercury leads to significant toxicity in adipocytes at exposures of 100 ng/mL during later stages of differentiation, but lower methylmercury concentrations produced little to no toxicity. Results also showed that VEGF secretion is elevated in adipocytes exposed to methylmercury after the process of differentiating into mature, fat-storing cells. These results provide a basis for further exploration into metabolic consequences of methylmercury exposure on specific cell types and cell models.

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