The therapeutic potential of neuroglobin-overexpressing human neural stem cells in a photothrombosis model.

BACKGROUND: Neuroglobin (NGB) is an oxygen-binding protein with neuroprotective properties under hypoxic and ischemic conditions. It promotes cell survival, reduces oxidative stress, and activates survival-related signaling pathways. This study aimed to evaluate whether overexpression of NGB in human neural stem cells (F3.NGB) could enhance their regenerative potential and therapeutic efficacy in photothrombosis model. METHODS: F3 cells were genetically engineered to overexpress NGB. In vitro proliferation and migration were assessed using CCK-8, colony forming, and scratch-based wound healing assays. In vivo, a photothrombosis-induced stroke model was used to evaluate infarct volume, transplanted cell migration and differentiation, and activation of proliferation-related signaling pathways following intravenous transplantation of F3.NGB cells. RESULTS: NGB overexpression significantly enhanced the proliferative capacity of F3 cells, and F3.NGB cells promoted N2A cell proliferation and actively migrated in co-culture conditions. In vivo, transplantation of F3.NGB cells resulted in a significant reduction in infarct volume compared with that in the controls. Western blot analysis showed increased activation of PI3K/AKT, mTOR, and ERK signaling pathways, with decreased PTEN expression. Immunohistochemical staining confirmed that F3.NGB cells migrated to the infarcted region, differentiated into neurons and astrocytes, and showed strong Ki67 positivity, indicating active proliferation at the injury site. CONCLUSION: These findings demonstrate that F3.NGB cells reduce ischemic brain damage primarily by enhancing cell proliferation, and also migrate to the injury site and undergo differentiation into neurons or astrocytes. These results suggest that F3.NGB cell-based therapy may contribute to the development of advanced regenerative strategies for the treatment of ischemic stroke.