Investigating Effects of Xenoestrogenic Chemicals on Digit Development in the CD-1 Mouse

Endocrine disrupting chemicals (EDCs) are substances that cause changes in the pathways of the endocrine system, which can lead to developmental disorders, cancers, and other diseases. It has been suggested that digit lengths... [ view full abstract ]

Endocrine disrupting chemicals (EDCs) are substances that cause changes in the pathways of the endocrine system, which can lead to developmental disorders, cancers, and other diseases. It has been suggested that digit lengths and length ratios are significantly affected by prenatal exposure to EDCs in humans, rats, and mice. To evaluate these changes as possible indicators of prenatal endocrine disruption, we have chosen to investigate their effects on digit development in the CD-1 mouse. We tested the effects of ethinyl estradiol, a known estrogen, and bisphenol S (BPS), a possible estrogen mimic, on digit lengths and ratios of prenatally exposed mice. Using X-ray imaging, we measured the lengths of the proximal and middle phalanges of offspring of exposed dams at 24, 35, and 63 days after birth. In addition, we are using immunohistochemistry (IHC) to assess whether prenatal exposure to EDCs causes changes in the expression of estrogen receptor or to cell proliferation during prenatal development. Ultimately, we hope to determine whether digit lengths and ratios can be utilized as novel endocrine disruption endpoints and to understand the biological mechanism behind developmental changes.