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Final Paper Proposal

One topic that has particularly fascinated me is the effects of endocrine disrupting compounds (EDC) on the brain. Chemicals that are prevalent in people's everyday lives, like Bisphenol-A (BPA) and phthalates, found in canned goods and plasticizers, respectively, can have profound impacts on brain function. Though BPA and phthalates are some of the most common EDC's, many others exist in products such as pesticides, herbicides and cosmetics. Interestingly, these effects can persist across multiple generations, altering the neurodevelopment of offspring that were never exposed to these EDC's first-hand. However, robust effects are also seen in animal models where the first generation were directly exposed to a specific EDC.

The reason I find EDC's so interesting is because the dysfunction they cause is a direct result of environmental exposure. Not only do these exogenous chemicals have detrimental consequences for the organism that is exposed to them, but for their offspring as well. These consequences include impaired hippocampal neurogenesis and altered gene expression in structures like the amygdala, hypothalamus (Hatcher, 2019) and PFC (Sadowski, 2014). To add another layer of complexity, many studies consider both males and females, noting sexual dimorphisms in how endocrine disruptors affect the brain and, in turn, behavior. Therefore, I think it is relevant to consider how epigenetic and neurodevelopmental changes due to EDC exposure can predispose individuals to psychiatric disorders such as PTSD, anxiety and schizophrenia in both males and females.


Sources:

Hatcher, K. M., Willing, J., Chiang, C., Rattan, S., Flaws, J. A., & Mahoney, M. M. (2019). Exposure to di-(2-ethylhexyl) phthalate transgenerationally alters anxiety-like behavior and amygdala gene expression in adult male and female mice. Physiology and Behavior, 207, 7-14. https://doi.org/10.1016/j.physbeh.2019.04.018


Jang, Y.J., Park, H.R., Kim, T.H., Yang, W., Lee, J., Choi, S.Y., Oh, S.B., Lee, E., Park, J., Kim, H., Kim, H.S., & Lee, J. (2012). High dose bisphenol A impairs hippocampal neurogenesis in female mice across generations. Toxicology, 296 1-3, 73-82 .

Kitraki E, Nalvarte I, Alavian-Ghavanini A, Rüegg J. Developmental exposure to bisphenol A alters expression and DNA methylation of Fkbp5, an important regulator of the stress response. Molecular and Cellular Endocrinology. 2015 Dec;417:191-199. DOI: 10.1016/j.mce.2015.09.028.

Sadowski, R.N., Wise, L.M., Park, P.Y., Schantz, S.L., & Juraska, J.M. (2014). Early exposure to bisphenol A alters neuron and glia number in the rat prefrontal cortex of adult males, but not females. Neuroscience, 279, 122-131.

Skinner MK, Anway MD, Savenkova MI, Gore AC, Crews D (2008) Transgenerational Epigenetic Programming of the Brain Transcriptome and Anxiety Behavior. PLoS ONE 3(11): e3745. doi:10.1371/journal.pone.0003745





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