title: Dehydroepiandrosterone effects on Akt signaling modulation in central nervous system of young and aged healthy rats.
abstract: Dehydroepiandrosterone (DHEA) is a steroid synthesized in adrenal cortex as well as in the nervous system. DHEA effects on central nervous system (CNS) have been associated with several brain functions such as marked neurotrophic and neuroprotective activity. DHEA plasma concentration decreases steadily with aging and studies have reported an inverse correlation between levels of DHEA and neurological diseases age-associated. Nonetheless, its mechanisms of action are not yet fully understood. Akt signaling pathway is one protein kinase which has been related to be DHEA modulated. The goal of this study was to investigate whether short-term (6 or 24h) or chronic (5 weeks) DHEA treatment modulates Akt in CNS of adult (3 months) and aged (18 and 24 months) healthy rats. Hypothalamus and hippocampus homogenates were prepared to quantify total-Akt and phosphorylated Akt at Ser(473) (pAkt). The results here presented have shown that acute (50mg/kg) and chronic (10mg/kg) DHEA injections modulate total and pAkt levels. This effect was dose and time-dependent as well as age and tissue-dependent. In addition, the age variable also intervenes on total and pAkt levels expression independently of DHEA treatment.
authors.affiliation: Laboratório de Interação Neuro-Humoral, Departamento de Fisiologia, Instituto de ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio grande do Sul, Brazil. daia janner@yahoo.com.br
authors.forename: Daiane da Rocha
authors.initials: Dda R
authors.lastname: Janner
authors.forename: Maria H V M
authors.initials: MH
authors.lastname: Jacob
authors.forename: Matheus P
authors.initials: MP
authors.lastname: Jahn
authors.forename: Luiz Carlos R
authors.initials: LC
authors.lastname: Kucharski
authors.forename: Maria Flávia Marques
authors.initials: MF
authors.lastname: Ribeiro
mesh_terms: D000276:Adjuvants, Immunologic / Q000008:administration & dosage / Q000494:pharmacology*; D000375:Aging / Q000187:drug effects; D000818:Animals; D003687:Dehydroepiandrosterone / Q000008:administration & dosage / Q000494:pharmacology*; D006624:Hippocampus / Q000187:drug effects*; D007031:Hypothalamus / Q000187:drug effects*; D008297:Male; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D015398:Signal Transduction / Q000187:drug effects
chemical_list: D000276:Adjuvants, Immunologic; D003687:Dehydroepiandrosterone; D051057:Proto-Oncogene Proteins c-akt