Absence of p75NTR gene decrease neurogenesis in the adult mouse hippocampus.

R. BERNABEU AND F. LONGO.

BMC NEUROSCIENCE

BIOMED CENTRAL LTD

Año: 2010 vol. 11 p. 136 - 147

1471-2202

Background: The ability to regulate neurogenesis in the adult dentate gyrus will require further identification andcharacterization of the receptors regulating this process. In vitro and in vivo studies have demonstrated thatneurotrophins and the p75 neurotrophin receptor (p75NTR) can promote neurogenesis; therefore we tested thehypothesis that p75NTR is expressed by adult dentate gyrus progenitor cells and is required for their proliferationand differentiation.Results: In a first series of studies focusing on proliferation, mice received a single BrdU injection and weresacrificed 2, 10 and 48 hours later. Proliferating, BrdU-positive cells were found to express p75NTR. In a second seriesof studies, BrdU was administered by six daily injections and mice were sacrificed 1 day later. Dentate gyrussections demonstrated a large proportion of BrdU/p75NTR co-expressing cells expressing either the NeuN neuronalor GFAP glial marker, indicating that p75NTR expression persists at least until early stages of maturation. In p75NTR(-/-) mice, there was a 59% decrease in the number of BrdU-positive cells, with decreases in the number of BrdUcells co-labeled with NeuN, GFAP or neither marker of 35%, 60% and 64%, respectively.Conclusions: These findings demonstrate that p75NTR is expressed by adult dentate progenitor cells and point top75NTR as an important receptor promoting the proliferation and/or early maturation of not only neural, but alsoglial and other cell types.