CircHECTD1 Regulates SPIO-labeled Human Mesenchymal Stem Cells For Tracer And Therapeutic Effects On Ischemic Stroke

Objective: Ischemic stroke is an acute cerebrovascular disease characterized by focal neurological deficits.To investigate the effect of circ HECTD1 on the differentiation of human bone marrow Mesenchymal Stem Cells(h MSCs)and the treatment of ischemic stroke,and to use the tracer superparamagnetic iron oxide(SPIO)to determine the dynamic distribution of h MSCs in the brain after ischemic stroke,which is helpful to update the existing stem cell therapy for ischemic stroke theory.Based on the treatment,it provides a new perspective and treatment strategy for the treatment of ischemic stroke.Methods: The h MSCs were labeled with superparamagnetic iron oxide(SPIO),the cell marker of SPIO-labeled h MSCs was detected by Prussian blue assay,the cell viability of h MSCs was detected by CCK-8 assay,and the proliferation of h MSCs was detected by Brd U assay.The knockdown efficiency of h MSCs transfected with si-circ HECTD1 lentivirus was detected by Real-time PCR.The expression levels of GFAP,TUJ1,PSD-95 and synaptophysin were detected by Western blot.The model of ischemic stroke was prepared by light-sensitive stroke.The T2 WI scan was performed 24 hours after the model was established.The stability of the infarct site and size was evaluated by MRI image.The brain micro-injection technique was used for ischemic SPIO-h MSCs with low expression of circ HECTD1 were transplanted after stroke,and animal behavioral experiments(cylinder task,grid walking,pasta handing)were used to evaluate the loss of motor function in mice,and the application of Nissl staining and immunization group The therapeutic effect was evaluated,and the staining pictures were further used to compare the traceability of SPIO-h MSCs in ischemic stroke.Results: SPIO with a concentration of 200 mg/ml can effectively label h MSCs as a tracer,and has no significant effect on cell activity,proliferation,migration and differentiation,suggesting the safety and efficiency of SPIO as a tracer-labeled stem cell.h MSCs have multifunctional differentiation potential and can induce differentiation into neuronal-like cells such as neuron-like cells and astrocytes.However,h MSCs knockdown of circ HECTD1 can promote the differentiation into neuron-like cells,and it is irreversible,but at the same time Inhibits cell proliferation and migration.At 24 h after the establishment of the PT model,the MRI image suggested a stable infarct area in the motor cerebral cortex motor function area,and no abnormal signal appeared in the Sham group.Animal behavioral experiments revealed that there was significant motor dysfunction and loss in the contralateral limbs of photothrombotic stroke(PT)model mice.SPIO-h MSCs knockdown circ HECTD1 expression after ischemic stroke can significantly improve the cause of ischemic stroke.Motor dysfunction,reducing the volume of cerebral infarction,promoting the proliferation of neurons in the infarct zone TUJ1 and presynaptic synaptophysin and post-synaptic PSD-95,play an active role in neuroprotection and long-term neuroplastic recovery.Conclusions: This study shows the SPIO as a tracer can efficiently label h MSCs,which is safe and stable.In this paper,a model of ischemic stroke in mice with light-sensitive stroke was successfully established.circ HECTD1 promoted the differentiation of SPIO-h MSCs into neuron-like cells and exerted positive effects through brain microinjection after ischemic stroke.Functional recovery,which provides new therapeutic strategies and therapeutic targets for clinical treatment of ischemic stroke.