title: Progesterone counteracts estrogen-induced increases in neurotrophins in the aged female rat brain.
abstract: Neurotrophin alterations have been associated with normal aging and age-related neurodegenerative disease, as well as cognitive status. Estrogen influences expression of mRNA and protein of neurotrophins and their receptors, and affects cognitive performance in young ovariectomized (Ovx) rats. The current investigation evaluated whether estrogen or estrogen plus progesterone affects neurotrophin protein levels in cognitive brain regions in the aged Ovx rat. While estrogen treatment increased BDNF, NGF, and NT3 levels in entorhinal cortex, progesterone abated the effects of estrogen resulting in neurotrophin levels comparable to aged Ovx rats not given hormone. Our findings suggest that the aged female brain is responsive to estrogen in cognitive brain regions, and that progesterone can reverse these estrogen effects.
authors.affiliation: Department of Physiology and Neuroscience and the Center on Aging, Medical University of South Carolina, 173 Ashley Avenue, Charleston, SC 29425. bimonte@musc.edu
authors.forename: Heather A
authors.initials: HA
authors.lastname: Bimonte-Nelson
authors.forename: Matthew E
authors.initials: ME
authors.lastname: Nelson
authors.forename: Ann-Charlotte E
authors.initials: AC
authors.lastname: Granholm
mesh_terms: D000367:Age Factors; D000375:Aging / Q000502:physiology*; D000818:Animals; D001921:Brain / Q000033:anatomy & histology / Q000187:drug effects*; D019208:Brain-Derived Neurotrophic Factor / Q000378:metabolism; D004347:Drug Interactions; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods; D004967:Estrogens / Q000494:pharmacology*; D005260:Female; D020932:Nerve Growth Factor / Q000378:metabolism; D009414:Nerve Growth Factors / Q000378:metabolism*; D020933:Neurotrophin 3 / Q000378:metabolism; D010052:Ovariectomy / Q000379:methods; D011374:Progesterone / Q000494:pharmacology*; D051381:Rats / Q000601:surgery; D011916:Rats, Inbred F344
chemical_list: D019208:Brain-Derived Neurotrophic Factor; D004967:Estrogens; D009414:Nerve Growth Factors; D020933:Neurotrophin 3; D011374:Progesterone; D020932:Nerve Growth Factor