[ effect of intravenous transplantation of adipose-derived stem cells on hippocampal neurogenesis after 6-hydroxydopamine induced injury]

ABSTRACT

Released dopamine from dopaminergic neurons in the substantia nigra pars compacta affects dentate gyrus [DG] neurogenesis in the hippocampus [HPC]. Damage to dopaminergic neurons in Parkinson's disease [PD] causes decreased neurogenesis in DG which results in memory impairment. This was an experimental laboratory study. We assessed the effect of intravenous transplantation of adipose-derived stem cells [ADSCs] on hippocampal neurogenesis after inducing injury by 6-OHDA [memory disability model of PD].We performed bilateral injections of 6-OHDA into substantia nigra [SNc] of male Wistar rats. First group of the rats received bilateral injections of 6-OHDA [6 micro g] dissolved in 2 micro l saline. Second group received saline injections instead of neurotoxin [sham group]. In the third group we transplanted the 3[rd] passage of ADSC cells which had been assessed for CD90 immunostaining [1×10[6] in 500 microl medium], via tail vein. The 4[th] group included injured rats which received an injection of the fluid of the culture media [500 micro l] through tail vein. After treatment, rats were sacrificed. The brains of the rats were removed, fixed with 4% paraformaldehyde, dehydrated, embedded in paraffin and cut into 10 micro m thick slices. We stained the sections with cresyl violet and determined the density of neurons in DG, CA1, CA3. Statistical analysis was performed by one-way ANOVA and Tukey test. P Neuron density in DG, CA1, CA3 showed significant decrease in the injured and medium treated groups compared to the sham group [P<0.00]. All so we found a significant increase in neuron density in these regions in the cell group in comparison to the medium treated and injured groups [p<0.000]. Intravenous injection of ADSCs protected hippocampal neurons from further damage in response to 6-OHDA.Therfore cell therapy can be a suitable method for the improvement of memory impairment in the patients with Parkinson's disease