TY - JOUR A1 - Hassouna, I. A1 - Ott, C. A1 - Wüstefeld, L. A1 - Offen, N. A1 - Neher, R. A. A1 - Mitkovski, M. A1 - Winkler, D. A1 - Sperling, S. A1 - Fries, L. A1 - Goebbels, S. A1 - Vreja, I. C. A1 - Hagemeyer, N. A1 - Dittrich, M. A1 - Rossetti, M. F. A1 - Kröhnert, K. A1 - Hannke, K. A1 - Boretius, S. A1 - Zeug, A. A1 - Höschen, C. A1 - Dandekar, T. A1 - Dere, E. A1 - Neher, E. A1 - Rizzoli, S. O. A1 - Nave, K.-A. A1 - Sirén, A.-L. A1 - Ehrenreich, H. T1 - Revisiting adult neurogenesis and the role of erythropoietin for neuronal and oligodendroglial differentiation in the hippocampus JF - Molecular Psychiatry N2 - Recombinant human erythropoietin (EPO) improves cognitive performance in neuropsychiatric diseases ranging from schizophrenia and multiple sclerosis to major depression and bipolar disease. This consistent EPO effect on cognition is independent of its role in hematopoiesis. The cellular mechanisms of action in brain, however, have remained unclear. Here we studied healthy young mice and observed that 3-week EPO administration was associated with an increased number of pyramidal neurons and oligodendrocytes in the hippocampus of similar to 20%. Under constant cognitive challenge, neuron numbers remained elevated until >6 months of age. Surprisingly, this increase occurred in absence of altered cell proliferation or apoptosis. After feeding a \(^{15}\)N-leucine diet, we used nanoscopic secondary ion mass spectrometry, and found that in EPO-treated mice, an equivalent number of neurons was defined by elevated \(^{15}\)N-leucine incorporation. In EPO-treated NG2-Cre-ERT2 mice, we confirmed enhanced differentiation of preexisting oligodendrocyte precursors in the absence of elevated DNA synthesis. A corresponding analysis of the neuronal lineage awaits the identification of suitable neuronal markers. In cultured neurospheres, EPO reduced Sox9 and stimulated miR124, associated with advanced neuronal differentiation. We are discussing a resulting working model in which EPO drives the differentiation of non-dividing precursors in both (NG2+) oligodendroglial and neuronal lineages. As endogenous EPO expression is induced by brain injury, such a mechanism of adult neurogenesis may be relevant for central nervous system regeneration. KW - neural stem-cells KW - recombinat-human-erythropoietin KW - cognitive functions KW - pyramidal neurons KW - nervous-sytem KW - brain-injury KW - mouse-brain KW - progenitors KW - mice KW - memory Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-186669 VL - 21 IS - 12 ER - TY - JOUR A1 - Spinelli, Simona A1 - Müller, Tanja A1 - Friedel, Miriam A1 - Sigrist, Hannes A1 - Lesch, Klaus-Peter A1 - Henkelman, Mark A1 - Rudin, Markus A1 - Seifritz, Erich A1 - Pryce, Christopher R. T1 - Effects of repeated adolescent stress and serotonin transporter gene partial knockout in mice on behaviors and brain structures relevant to major depression JF - Frontiers in Behavioral Neuroscience N2 - In humans, exposure to stress during development is associated with structural and functional alterations of the prefrontal cortex (PFC), amygdala (AMY), and hippocampus (HC) and their circuits of connectivity, and with an increased risk for developing major depressive disorder particularly in carriers of the short (s) variant of the serotonin transporter (5-HTT) gene-linked polymorphic region (5-HTTLPR). Although changes in these regions are found in carriers of the s allele and/or in depressed patients, evidence for a specific genotype x developmental stress effect on brain structure and function is limited. Here, we investigated the effect of repeated stress exposure during adolescence in mice with partial knockout of the 5-HIT gene (HET) vs. wildtype (WT) on early-adulthood behavioral measures and brain structure [using magnetic resonance imaging (MRI)] relevant to human major depression. Behaviorally, adolescent stress (AS) increased anxiety and decreased activity and did so to a similar degree in HET and WT. In a probabilistic reversal learning task, HET-AS mice achieved fewer reversals than did HET-No-AS mice. 5-HIT genotype and AS were without effect on corticosterone stress response. In terms of structural brain differences, AS reduced the volume of two long-range white matter tracts, the optic tract (OT) and the cerebral peduncle (CP), in WT mice specifically. In a region-of-interest analysis, AS was associated with increased HC volume and HET genotype with a decreased frontal lobe volume. In conclusion, we found that 5-HIT and AS genotype exerted long-term effects on behavior and development of brain regions relevant to human depression. KW - mouse-brain KW - white-matter integrity KW - linked polymorphic region KW - C57BL/6 mice KW - lerned helplessness KW - 5-HTTLPR polymorphism KW - childhood maltreatment KW - rhesus macaques KW - 3-dimensional MRI KW - life stress Y1 - 2013 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-122240 VL - 7 ER -