@article{marinello_gillera_fanning_malinsky_rhodes_horman_patisaul_2022, title={Effects of developmental exposure to FireMaster (R) 550 (FM 550) on microglia density, reactivity and morphology in a prosocial animal model}, volume={91}, ISSN={["1872-9711"]}, url={http://dx.doi.org/10.1016/j.neuro.2022.04.015}, DOI={10.1016/j.neuro.2022.04.015}, abstractNote={Microglia are known to shape brain sex differences critical for social and reproductive behaviors. Chemical exposures can disrupt brain sexual differentiation but there is limited data regarding how they may impact microglia distribution and function. We focused on the prevalent flame retardant mixture Firemaster 550 (FM 550) which is used in foam-based furniture and infant products including strollers and nursing pillows because it disrupts sexually dimorphic behaviors. We hypothesized early life FM 550 exposure would disrupt microglial distribution and reactivity in brain regions known to be highly sexually dimorphic or associated with social disorders in humans. We used prairie voles (Microtus ochrogaster) because they display spontaneous prosocial behaviors not seen in rats or mice and are thus a powerful model for studying chemical exposure-related impacts on social behaviors and their underlying neural systems. We have previously demonstrated that perinatal FM 550 exposure sex-specifically impacts socioemotional behaviors in prairie voles. We first established that, unlike in rats, the postnatal colonization of the prairie vole brain is not sexually dimorphic. Vole dams were then exposed to FM 550 (0, 500, 1000, 2000 µg/day) via subcutaneous injections through gestation, and pups were directly exposed beginning the day after birth until weaning. Adult offspring's brains were assessed for number and type (ramified, intermediate, ameboid) of microglia in the medial prefrontal cortex (mPFC), cerebellum (lobules VI-VII) and amygdala. Effects were sex- and dose-specific in the regions of interests. Overall, FM 550 exposure resulted in reduced numbers of microglia in most regions examined, with the 1000 µg FM 550 exposed males particularly affected. To further quantify differences in microglia morphology in the 1000 µg FM 550 group, Sholl and skeleton analysis were carried out on individual microglia. Microglia from control females had a more ramified phenotype compared to control males while 1000 µg FM 550-exposed males had decreased branching and ramification compared to same-sex controls. Future studies will examine the impact on the exposure to FM 550 on microglia during development given the critical role of these cells in shaping neural circuits.}, journal={NEUROTOXICOLOGY}, publisher={Elsevier BV}, author={Marinello, William P. and Gillera, Sagi Enicole A. and Fanning, Marley J. and Malinsky, Lacey B. and Rhodes, Cassie L. and Horman, Brian M. and Patisaul, Heather B.}, year={2022}, month={Jul}, pages={140–154} } @article{rebuli_gibson_rhodes_cushing_patisaul_2016, title={Sex differences in microglial colonization and vulnerabilities to endocrine disruption in the social brain}, volume={238}, ISSN={["1095-6840"]}, DOI={10.1016/j.ygcen.2016.04.018}, abstractNote={During development, microglia, the resident immune cells of the brain, play an important role in synaptic organization. Microglial colonization of the developing brain is sexually dimorphic in some regions, including nuclei critical for the coordination of social behavior, suggesting steroid hormones have an influencing role, particularly estrogen. By extension, microglial colonization may be vulnerable to endocrine disruption. Concerns have been raised regarding the potential for endocrine disrupting compounds (EDCs) to alter brain development and behavior. Developmental exposure to Bisphenol A (BPA), a ubiquitous EDC, has been associated with altered sociosexual and mood-related behaviors in various animal models and children. Through a comparison of the promiscuous Wistar rat (Rattus norvegicus) and the socially monogamous prairie vole (Microtus ochrogaster), we are the first to observe that developmental exposure to the synthetic estrogen ethinyl estradiol (EE) or BPA alters the sex-specific colonization of the hippocampus and amygdala by microglia.}, journal={GENERAL AND COMPARATIVE ENDOCRINOLOGY}, author={Rebuli, Meghan E. and Gibson, Paul and Rhodes, Cassie L. and Cushing, Bruce S. and Patisaul, Heather B.}, year={2016}, month={Nov}, pages={39–46} }