INBIOMED   24026
INSTITUTO DE INVESTIGACIONES BIOMEDICAS
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Ovarian hormones induce the expression and release of astroglial mitochondrial-encoded rat humanin in vitro
Autor/es:
DENING MB; SEILICOVICH A; ZÁRATE S; TRAETTA ME; CODAGNONE M; REINÉS A
Lugar:
París
Reunión:
Congreso; Congreso de la International Society for Neurochemistry; 2017
Institución organizadora:
International Society for Neurochemistry
Resumen:
Ovarian hormones exert neuroprotective actions in part by directeffects on neurons but also indirectly by regulating the release ofneurotrophic factors by astrocytes. Ovarian hormone loss duringmenopause is associated with brain hypometabolism, synapticfailure and increased risk of neurodegeneration. Humanin (HN) isa mitochondrial-derived peptide with cytoprotective, metabolic, andanti-inflammatory effects in multiple cell types and animal models;it is localized in tissues with high metabolic rates and its expressiondecreases with age. Our previous studies in vivo show that HNcolocalizes with astrocyte markers and its expression decreases inthe hippocampus of hormone-deprived female rats. Still, little isknown about ovarian hormone regulation of HN expression andsecretion by astrocytes and the effects of this peptide on neuronalfunction. The aim of this work was to study the direct actions ofestradiol and progesterone on the expression and release of HN byhippocampal astrocytes in vitro. To this aim, cultured astrocyteswere incubated with estradiol (E, 1 nM), progesterone (P, 1 lM),E+P or vehicle for 24 h. Intracellular HNr expression was evaluatedby immunocytochemistry and secreted HNr was determined byELISA in the conditioned media. Our results show that HNr isexpressed in astrocytes in vitro and that ovarian hormones increasedits levels. The incubation with E+P was the most effective treatmentto induce HNr secretion by astrocytes. Our results indicate thatovarian hormones positively regulate HN expression and release byastrocytes. Further experiments will assess the effect of astrocyteHN on neuronal function. The knowledge of HN effects in braincells and its regulation by ovarian hormones could help find newtherapeutic targets for interventions that may promote a healthierlifespan for post-menopausal women.88 Journal of Neurochemistry © 2017 International Society for Neurochemistry, J. Neurochem. (2017) 142 (Suppl. 1), 78--164©