Neuroprotective effect of artemin modified bone marrow mesenchymal stem cells on dopaminergic neurons

Abstract

Objective To discuss the protective effect of Artemin (ARTN) on 6-hydroxydopamine (6-OHDA)-mediated neurotoxic injury, and the alternations of related proteins in Parkinson’s disease (PD) model rats. Methods Bone marrow mesenchymal stem cells (MSCs) were isolated and cultured in vitro. After being transfected with recombinant lentiviral vectors carrying ARTN gene, MSCs stably expressed ARTN were chosen (Lv-ARTN-MSCs cells). The SH-SY5Y cells were treated with supernatant of Lv-ARTN-MSCs prior to 6-OHDA treatment, and then, cell survival rate was measured by MTT assay and morphologic changes in cultured SH-SY5Y cells were observed by fluorescence microscope (Hochest33258 staining). PD rat models were established and randomly divided into four groups (n=6): PD group, MSCs group, Lv-MSCs group and Lv-ARTN-MSCs group; and sham-operated group (n=6) was also chosen. The PD, MSCs, Lv-MSCs and Lv-ARTN-MSCs groups were transplanted with 5 μL of saline, MSCs (1.0×105 cell/5 μL), empty virus modified MSCs (1.0×105 cell/5 μL) and ARTN gene modified MSCs (1.0×105 cell/5 μL), respectively, into the left striatum; rats in the sham-operated group were injected with saline when rats in the other groups were received 6-OHDA injection (the same surgical procedures and coordinates). The expressions of tyrosine hydroxylase (TH) and dopamine transporter (DAT) in the striatum were measured by Western blotting. Results Western blotting indicated obvious ARTN protein expressions in the Lv-ARTN-MSCs groups. The supernatant of Lv-ARTN-MSCs could effectively reduce the apoptosis rate induced by 6-OHDA; as compared with that of SH-SY5Y cells in the 6-OHDA group, the cell survival rate in the Lv-ARTN-MSCs group increased by 13.67%, with significant difference (P<0.05). Eight weeks after transplantation, the levels of TH and DAT protein in the striatum were elevated significantly in MSCs group, Lv-MSCs group and Lv-ARTN-MSCs group as compared with those in the PD group (P<0.05), and the Lv-ARTN-MSCs group showed the most significant improvement. Conclusion ARTN which is a secreted protein can protect dopaminergic neuron against 6-OHDA-induced toxicities in Parkinson’s disease, and the mechanism might be related to the increased expressions of TH and DAT. Key words: Parkinson’s disease; Mesenchymal stem cell; Artemin gene; Gene transfection