Sexually dimorphic effects of gestational endocrine-disrupting chemicals on microRNA expression in the developing rat hypothalamus. (15th October 2015)

• Record Type: Journal Article
• Authors: Topper, Viktoria Y.; Walker, Deena M.; Gore, Andrea C.
• Is Part Of: Molecular and cellular endocrinology. Volume 414(2015)
• Page Start: 42
• Page End: 52
• Publication Date: 2015-10-15
• Subjects: Endocrine-disrupting chemicals (EDCs) -- Polychlorinated biphenyls (PCBs) -- MicroRNA -- Hypothalamus -- Medial preoptic nucleus (MPN) -- Ventromedial nucleus (VMN); Endocrinology -- Periodicals; Molecular biology -- Periodicals; Cytology -- Periodicals; Endocrinology -- Periodicals; Hormones -- Periodicals; Endocrinologie -- Périodiques; Cytology; Endocrinology; Molecular biology; Periodicals; 573.4
• DOI: 10.1016/j.mce.2015.07.013
• Languages: English
• ISSNs: 0303-7207

Abstract

Abstract: This study examined developmental changes and sexual dimorphisms in hypothalamic microRNAs, and whether gestational exposures to environmental endocrine-disrupting chemicals (EDCs) altered their expression patterns. Pregnant rat dams were treated on gestational days 16 and 18 with vehicle, estradiol benzoate, or a mixture of polychlorinated biphenyls. Male and female offspring were euthanized on postnatal days (P) 15, 30, 45, or 90, and microRNA and mRNA targets were quantified in the medial preoptic nucleus (MPN) and ventromedial nucleus (VMN) of the hypothalamus. MicroRNAs showed robust developmental changes in both regions, and were sexually dimorphic in the MPN, but not VMN. Importantly, microRNAs in females were up-regulated by EDCs at P30, and down-regulated in males at P90. Few changes in mRNAs were found. Thus, hypothalamic microRNAs are sensitive to prenatal EDC treatment in a sex-, developmental age-, and brain region-specific manner. Highlights: MicroRNAs in the MPN change with development. Prenatal PCBs increase microRNA expression in the MPN of females at P30. Prenatal PCBs decrease microRNA expression in the MPN of males at P90. MicroRNAs in the VMN increase with development, but have few PCB effects. Targeted mRNA expression did not have a clear relationship to the microRNA changes.