Inhibitory effects of brain-derived neurotrophic factor precursor on viability and neurite growth of murine hippocampal neurons

Objective To explore the mediation effect of p75 neurotrophin receptor (p75NTR) in the effect of brainderived neurotrophic factor precursor (proBDNF) on viability and neurite growth of murine hippocampal neurons. Methods Hippocampal neurons were obtained from p75NTR+/+ and p75NTR-/- 18-day mice and primarily cultured. For p75NTR+/+ neurons, three experimental groups were set, i.e. control, proBDNF (30ng/ml), and proBDNF (30ng/ml)+p75/Fc (30µg/ml) groups. For p75NTR-/- neurons, two experimental groups were set, i.e. control and proBDNF (30ng/ml) groups. MTT assays were performed after 24h to examine the viability of neonatal primary neurons. Immunofluorescent staining was conducted after 72h to investigate the neurite length. Results With MAP2 and DAPI double fluorescent staining it was identified that the neonatal hippocampal neurons were successfully cultured in vitro with high purity. For viability assay of p75NTR+/+ neurons, it was found that the absorbance value at 570nm (A570) in proBDNF group was significantly lower than that in control group (P0.05). With neurite growth assay of p75NTR+/+ neurons, it was found that the neurite length in proBDNF group was significantly shorter than that in control group (P0.05). With neurite growth assay of p75NTR-/- neurons, no difference in neurite length was observed between proBDNF group and control group. Conclusion proBDNF may inhibit the neuronal viability and neurite growth via p75NTR. DOI: 10.11855/j.issn.0577-7402.2014.09.03