Intervention effects of enriched environment on brain damage of MPTP-induced senescence-accelerated prone mice

Abstract

Objective To observe the effects of enriched environmen(EE) on brain-derived neurotrophic factor(BDNF) in substantia nigra(SN) of senescence-accelerated prone mice,so as to explore the possible mechanism of EE in alleviating MPTP induced damage and in protecting dopaminergic neurons in the SN.Methods Totally 80 3-month old female SAMP8 mice were averagely assigned to EE and standard environment(SE) groups at random.After three months,the mice in each group were further divided into 2 subgroups at random:MPTP group and NS group(n = 20).The MPTP groups received subcutaneous injection of MPTP,and the NS mice were treated with an equal volume of NS.At the seventh day,the mice were sacrificed for RT-PCR and immunohistochemistry staining.RT-PCR was used to examine BDNF mRNA expression and immunohistochemistry staining was used to examine BDNF-ir expression.Results Compared with SE + NS mice,EE + NS mice had significantly increased BDNF mRNA expression(P 0.01),and the number of BDNF-ir cell and COD values in SN were also significantly increased(P 0.01).Compared with SE + NS mice,SE + MPTP mice showed significantly decreased BDNF mRNA expression(P 0.001),and the number of BDNF-ir cells and the COD values in SN of mice were significantly decreased(P 0.01).Compared with SE + MPTP mice,EE + MPTP mice showed increased BDNF mRNA expression(P 0.01),and the number of BDNF-ir cells and the COD values in SN were significantly increased(P 0.01).Conclusion EE can increase BDNF mRNA expression and BDNF-ir cell number in SN of SAMP8 mice,alleviating MPTP-induced SN damage.