Recombinant AAV-mediated Expression of Human BDNF Protects Neurons against Cell Apoptosis in Aβ-induced Neuronal Damage Model

The human brain-derived neurotrophic factor (hBDNF) gene was cloned by polymerase chain reaction and the recombinant adeno-associated viral vector inserted with hBDNF gene (AAV-hBDNF) was constructed. Cultured rat hippocampal neurons were treated with Aβ25-35 and se- rued as the experimental Aβ-induced neuronal damage model (AD model), and the AD model was infected with AAV-hBDNF to explore neuroprotective effects of expression of BDNF. Cell viability was assayed by MTT. The expression of bcl-2 anti-apoptosis protein was detected by immunocyto- chemical staining. The change of intracellular free Ca ion ([Ca2 ]i) was measured by laser scanning confocal microscopy. The results showed that BDNF had protective effects against Aβ-induced neu- ronal damage. The expression of the bcl-2 anti-apoptosis protein was raised significantly and the bal- ance of [Ca2 ]i was maintained in the AAV-hBDNF treatment group as compared with AD model group. These data suggested that recombinant AAV mediated a stable expression of hBDNF in cul- tured hippocampal neurons and resulted in significant neuron protective effects in AD model. The BDNF may reduce neuron apoptosis through increasing the expression of the bcl-2 anti-apoptosis protein and inhibiting intracellular calcium overload. The viral vector-mediated gene expression of BDNF may pave the way of a novel therapeutic strategy for the treatment of neurodegenerative dis- eases such as Alzheimer’s disease.