The broad long-term goal of the proposed research is to understand the functions of 17beta-estradiol (estrogen; E2) and estrogen receptors (ERs) in the developing nervous system and to determine to what extent environmental estrogens influence these functions. E2 influences the development and function of many regions of the brain in both males and females. Thus, it is possible that other estrogenic compounds can impact development of the brain. Environmental estrogens, also known as """"""""endocrine disrupters,"""""""" are a diverse group of compounds that can mimic or antagonize the normal actions of E2. The extent to which environmental estrogens impact the developing nervous system is unclear. Proposed experiments employing primary cultures of neonatal rat cerebellar neurons and the developing cerebellum as models will address the following Specific Aims-Specific Aim 1: Determine whether E2 modulates cellular signaling in developing cerebellar neurons through rapid, non-genomic actions on MAPK signal transduction;
Specific Aim 2 : Determine the networks of estrogen responsive genes whose expression is modulated by E2 in cerebellar neurons;
Specific Aim 3 : Determine to what degree representative environmental estrogens mimic or inhibit the effects of E2 in developing cerebellar neurons.
Specific Aims 1 & 2 test the hypothesis that E2 normally functions in developing neurons by rapidly modulating the activity of MAPK signaling, and also through genomic ER-mediated mechanisms which together, modify expression of discrete networks of gene products.
Specific Aim 3 will test the hypothesis that environmental estrogens influence developing neurons by modifying both MAPK signaling and genomic ER-mediated mechanisms, which results in altered networks of expressed genes. All three Specific Aims will be addressed through experiments using activation-state specific antisera to determine E2-mediated signaling pathways and by cDNA array and RT -PCR analysis of E2-responsive gene expression. From these results a neuronal """"""""E2-signature cDNA array"""""""" will be developed and used in Aim 3 to determine how environmental estrogens influence E2-responsive gene expression in these developing neurons.

Agency
National Institute of Health (NIH)
Institute
National Institute of Neurological Disorders and Stroke (NINDS)
Type
Research Project (R01)
Project #
1R01NS042798-01A1
Application #
6542318
Study Section
Alcohol and Toxicology Subcommittee 4 (ALTX)
Program Officer
Edwards, Emmeline
Project Start
2002-06-01
Project End
2005-05-31
Budget Start
2002-06-01
Budget End
2003-05-31
Support Year
1
Fiscal Year
2002
Total Cost
$229,500
Indirect Cost
Name
University of Cincinnati
Department
Pharmacology
Type
Schools of Medicine
DUNS #
City
Cincinnati
State
OH
Country
United States
Zip Code
45221
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Kirby, Michelle; Zsarnovszky, Attila; Belcher, Scott M (2004) Estrogen receptor expression in a human primitive neuroectodermal tumor cell line from the cerebral cortex: estrogen stimulates rapid ERK1/2 activation and receptor-dependent cell migration. Biochem Biophys Res Commun 319:753-8
Ge, Yun; Belcher, Scott M; Pierce, Dwight R et al. (2004) Detection of Purkinje cell loss following drug exposures to developing rat pups using reverse transcriptase-polymerase chain reaction (RT-PCR) analysis for calbindin-D28k mRNA expression. Toxicol Lett 150:325-34
Ge, Yun; Belcher, Scott M; Light, Kim E (2004) Alterations of cerebellar mRNA specific for BDNF, p75NTR, and TrkB receptor isoforms occur within hours of ethanol administration to 4-day-old rat pups. Brain Res Dev Brain Res 151:99-109
Ge, Yun; Belcher, Scott M; Pierce, Dwight R et al. (2004) Altered expression of Bcl2, Bad and Bax mRNA occurs in the rat cerebellum within hours after ethanol exposure on postnatal day 4 but not on postnatal day 9. Brain Res Mol Brain Res 129:124-34
Zsarnovszky, Attila; Belcher, Scott M (2004) Spatial, temporal, and cellular distribution of the activated extracellular signal regulated kinases 1 and 2 in the developing and mature rat cerebellum. Brain Res Dev Brain Res 150:199-209
Wong, Jeremy K; Le, Hoa H; Zsarnovszky, Attila et al. (2003) Estrogens and ICI182,780 (Faslodex) modulate mitosis and cell death in immature cerebellar neurons via rapid activation of p44/p42 mitogen-activated protein kinase. J Neurosci 23:4984-95
Zsarnovszky, Attila; Smith, Todd; Hajos, Ferenc et al. (2002) Estrogen regulates GFAP-expression in specific subnuclei of the female rat interpeduncular nucleus: a potential role for estrogen receptor beta. Brain Res 958:488-96