Therapeutic effects of intranigral transplantation of mesenchymal stem cells in rat models of Parkinson's disease

Stem cell transplantation is a promising tool for the treatment of neurodegenerative disorders, including Parkinson's disease (PD); however, the therapeutic routes and mechanisms of mechanical approaches to stem cell transplantation must be explored. This study tests the therapeutic effect of transplantation of rat bone marrow mesenchymal stem cells (MSCs) into the substantia nigra (SN) of the PD rat. 5‐Bromo‐2‐deoxyuridine‐labeled rat MSCs were transplanted into the SN of the 6‐hydroxydopamine‐injected side of PD rat brains. The behavioral changes in PD rats were examined before and 4 and 8 weeks after MSC transplantation. The expression of tyrosine hydroxylase (TH) in the SN and the striatum and the survival and differentiation of MSCs were assessed by immunohistochemical and double immunofluorescence techniques. Abnormal behavior of PD rats was significantly improved by the administration of bone marrow MSCs, and the number of TH‐positive cells in the SN and the optical density of TH‐positive fibers in the striatum were markedly increased. Transplanted MSCs can survive and migrate in the brain and differentiate into nestin‐, neuron‐specific enolase‐, and GFAP‐positive cells. Our findings suggest that transplantation of rat bone marrow MSCs into the SN of PD rats may provide therapeutic effects. © 2016 Wiley Periodicals, Inc. The rat bone marrow mesenchymal stem cells (MSCs) were isolated, cultured and passaged, and then their neural differentiation potentials were identified by immunocytochemistry. After the MSCs were labeled by 5‐bromo‐2‐deoxyuridine (BrdU), the Brdu‐labeled cells were injected into substantia nigra of the 6‐OHDA‐injected side at one point of the rats of Parkinson's disease (PD). The rotational behavior of the PD rats in each group before and after transplant was evaluated by apomorphine intraperitoneal injection. The tyrosine hydroxylase (TH)‐immunoreactive cells and fibers in the substantia nigra and the striatum were calculated, and the survival, migration and differentiation of the implanted MSCs in vivo were examined.