Molecular Mechanism of Bone Marrow Mesenchymal Stem Cell Derived Exosomes on Vascular Repair in Rats with Brain Injury

To explore the molecular mechanism of exosomes derived from bone marrow mesenchymal stem cells on vascular repair in rats with brain injury. 30 Sprague-Dawley rats were used in this study. Bone marrow was extracted from the posterior iliac crest of the rat under general anesthesia and bone marrow mesenchymal stem cells were isolated and cultured. Some rats were treated with middle cerebral artery occlusion surgery to induce acute brain injury models. The protein expressions of vascular endothelial growth factor A and vascular endothelial growth factor receptor 2 were analyzed by western blot. Polymerase chain reaction was used to analyze the messenger RNA expressions of endothelin-1, vascular cell adhesion molecule 1 and endothelial nitric oxide synthase related to endothelial cell damage. The protein expressions of vascular endothelial growth factor A and vascular endothelial growth factor receptor 2 in the model group was lower than that in the control group (p<0.05) and the protein expressions in the treatment group was higher than that in the model group (p<0.05). The messenger RNA expressions of endothelin-1 and vascular cell adhesion molecule 1 in the model group increased while the expression of endothelial nitric oxide synthase messenger RNA decreased (p<0.05). The messenger RNA expressions of endothelin-1 and vascular cell adhesion molecule 1 in the treatment group decreased and the messenger RNA expression of endothelial nitric oxide synthase increased (p<0.05). The apoptosis level of endothelial cells in the model group increased and in the treatment group was reduced. Exosomes derived from bone marrow mesenchymal stem cells could effectively regulate cell survival, promote angiogenesis, protect nerve cells and improve the prognosis of stroke in rats by up regulating the expression of C-X-C chemokine receptor type 4 in bone marrow mesenchymal stem cells.