The Mechanism Of Panax Notoginseng Saponins Affecting The Ultrastructure Of Cerebral Neurovascular Unit In Ischemic Stroke Rats Through MiRNA Regulatory Network

Objective: To observe the effect of Panax notoginseng saponins(PNS)on the ultrastructure and miRNA expression profile of cerebral neurovascular unit(NVU)in ischemic stroke rats,and to preliminarily explore the brain protective effect of Panax notoginseng saponins through the miRNA regulatory network based on bioinformatics technology.In order to provide new targets and related theoretical support for Panax notoginseng saponins in the treatment of ischemic stroke.Methods:(1)To observe the effects of Panax notoginseng saponins on the morphological changes and neurological function of the ultrastructure of cerebral neurovascular unit in ischemic stroke rats.Thirty healthy male SD rats were randomly divided into three groups to establish a rat model of ischemia-reperfusion injury.Panax notoginseng saponins intervention group,control group and sham-operated group were made.Neurological deficits were scored 7 days after ischemia.Then,some brain tissue samples were taken,and electron microscope was used to observe the microvessels,neurons and glial cells in the brain tissue.Analysis of the effects of Panax notoginseng saponins on brain ultrastructural morphology after cerebral ischemia(2)miRNA microarray chip technology was used to detect the difference of miRNA expression profiles in the brain tissue of rats after ischemic brain injury and after intervention with Panax notoginseng saponins,and screened out the differentially expressed miRNAs after medication.7 days after cerebral ischemia-reperfusion in rats,the neurological deficits of rats were scored,and then the brain tissue was decapitated,the total RNA of the brain tissue was extracted,miRNA was isolated and labeled,and the intervention group was detected and analyzed by high-throughput miRNA microarray chip technology Compared with the differences in miRNA expression profiles between the control group,the intervention group and the sham-operated group,the differentially expressed miRNAs after the intervention of Panax notoginseng saponins were screened out,and the relationship between the differentially expressed miRNAs and drugs was further analyzed.(3)The target genes of differentially expressed miRNAs and the signaling pathways involved in target genes were predicted using bioinformatics technology.The differentially expressed miRNA target genes were predicted by the miRNA target gene database mi RGen3.0(with the 3’UTR of the transcriptome as the target to be predicted)to obtain the differentially expressed miRNA target genes;GO database,KEGG database,etc.Perform enrichment analysis on the function and pathway of the target gene,and study the biological function and signal transduction pathway of the target gene.Results:(1)Neurological function score: Before the intervention,that is,4 hours after the operation,there was no significant difference in the neurological function scores between the intervention group and the control group;after the PNS intervention,the neurological function scores of the rats in the intervention group gradually improved,and the neurological deficit scores of the rats in the intervention group 7 days after ischemia-reperfusion were significantly different from those of the rats at the same time.Compared with the control group,the difference was statistically significant(P<0.05).(2)Electron microscopy results of the ultrastructure of cerebral neurovascular of the three groups of rats: There were no obvious changes in the structure of neurons,glial cells and microvessels in the sham operation group,while the neurons,glial cells and microvessels in the intervention group and the control group were all damaged.To a certain extent,the injury in the intervention group was lighter than that in the control group.(3)Through the detection of microarray chip,we found that there were 680 differentially expressed miRNAs in the intervention group compared with the control group,of which a total of15 mature miRNAs showed significant differences in the NVU of ischemic stroke rats.Differentially expressed;714 miRNAs were differentially expressed between the intervention group and the sham operation group,of which 74 miRNAs had significant differences between the groups;There were significant differences in both comparisons,which were up-regulated.(4)There are 59 target genes corresponding to rno-mir-483.The selected target genes are analyzed by GO and KEGG using the Metascape database,and a total of 7 significantly enriched GO terms and 1 significantly enriched pathway are obtained.,the miRNA regulatory network was analyzed,and the significantly related proteins FIBIN,FOXRED2 and NAAA were obtained.Conclusion: In the rat model of cerebral ischemia-reperfusion,this study screened the differentially expressed miRNAs in the brain tissue of ischemic stroke rats after treatment with Panax notoginseng saponins.By predicting the biological processes and signaling pathways involved in target genes,we found that rno-mir-483 is closely related to the ultrastructure of cerebral neurovascular unit protective effect of Panax notoginseng saponins,and may be a key miRNA in the pathway.The target gene of rno-mir-483 and the proteins FIBIN,FOXRED2 and NAAA induced by the target gene play a role in brain protection.