Transplantation of BM-MScs promotes angiogenesis and decreases superoxide levels in the brain of hypertensive rats: relevance for homologous transplantation as stroke therapy

Mesenchymal stem cells (MSCs) hold tremendous potential for tissue regeneration. It has been hypothesized that the action of these cells is not only to repopulate the injured area, but mainly to secrete neurotrophic and proliferative factors which could induce or stimulate the recovery of tissue. Our aim was to investigate if transplanted bone marrow MSCs could have antioxidant effect by decreasing the production of superoxide anion. Methods We performed a comparison brain tissue isolated from SHRSP treated or not with MSCs with those from normotensive Wistar Kyoto (WKY) controls by qPCR, immunohistochemistry and biochemistry assays. MSCs were obtained from the femur and tibiae of 12-week-old WKY rats, labeled with CFSE and injected into cistern magna through the atlanto-occipital membrane of 48-week-old SHRSP rats. We also evaluated the expression of VEGF and Nitric oxide (NO) was to access its possible role in neural proliferation or endogenous brain cells regeneration. Results An increase of almost threefold of VEGF expression was observed in the MSC-treated SHRSP group, thereby suggesting that transplanted stem cells have a proliferative potential. Similar results were obtained in terms of elevation of generated NO detected by chemiluminescence. Thus, we suggest that both Vegf and NO can contribute to the recovery of hippocampal damage associated with oxidative stress and apoptosis in the spontaneously hypertensive stroke model SHRSP. Conclusion Our data suggests that MSCs could secrete or induce the same types of proliferation factors, such as VEGF and NO, which could stimulate the recovery of brain damage by endogenous stem cells. Thus, stem cell transplantation is a promising therapy, which could provide trophic support, helping promote survival, migration, and differentiation of endogenous precursor cells.