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Belcher, S.

Publications and source records attributed to Belcher, S..

2 recordsLinked to original sources

Effects of Bisphenol A on Incidence and Severity of Cardiac Lesions in the NCTR-Sprague-Dawley Rat: A CLARITY-BPA Study

The goal of this study was to determine whether bisphenol A (BPA) had adverse effects indicative of cardiac toxicity. As part of the \"Consortium Linking Academic and Regulatory Insights on BPA Toxicity\" (CLARITY-BPA), study dams and offspring were exposed by daily gavage to five doses of BPA ranging from 2.5 to 25000 g/kg/day, 0.05 or 0.5 g/kg/day 17-ethinyl-estradiol (EE) or 0.3% carboxymethylcellulose vehicle. Exposure-related effects were analyzed in isolated hearts by quantitative morphometry and histopathology. No dose-related changes in body weight were detected. Across all exposure groups including vehicle controls, body weight of continuously dosed males was reduced compared to males dosed only until PND21. Heart weight was increased only in females exposed to EE, and consistent alterations in LV wall thickness were not observed. Exposure-related changes in collagen accumulation were minor and limited to highest EE exposure groups with increased collagen accumulation in PND21 males. Decreased collagen was observed in hearts of BPA or EE exposed females at PND90 and PND180. In BPA or EE treated females cardiomyopathy incidence and severity was significantly increased compared to control females at PND21 with myocardial degeneration observed in both males and females at PND21 and PND90.

pharmacology and toxicology

Impacts of Bisphenol A and Ethinyl Estradiol on Male and Female CD-1 Mouse Spleen

The endocrine disruptor bisphenol A (BPA) and the pharmaceutical 17-ethinyl estradiol (EE) are synthetic chemicals with estrogen-like activities. Despite ubiquitous human exposure to BPA, and the wide-spread clinical use of EE as oral contraceptive adjuvant, the impact of these estrogenic endocrine disrupting chemicals (EDCs) on the immune system is unclear. Here we report results of in vivo dose response studies that analyzed the histology and microstructural changes in the spleen of adult male and female CD-1 mice exposed to 4 to 40,000 g/kg/day BPA or 0.02 to 2 g/kg/day EE from conception until 12-14 weeks of age. Results of that analysis indicate that both BPA and EE have dose- and sex-specific impacts on the cellular and microanatomical structures of the spleens that reveal minor alterations in immunomodulatory and hematopoietic functions. These findings support previous studies demonstrating the murine immune system as a sensitive target for estrogens, and that oral exposures to BPA and EE have important estrogen-like immunomodulatory affects in both sexes of the CD-1 mouse.

pharmacology and toxicology