Expression Of MicroRNA In Hippocampus Tissue And Cells Of Diabetic Encephalopathy Rats

Objective: To explore the role of microRNA in the pathogenesis of Diabetic Encephalopathy(DE)by detecting the changes of microRNA expression in rat hippocampus and primary rat hippocampal neurons of DE.Methods:We Randomly selected 10 rats as control group and the rest 30 as modeling group using random number table method.The streptozotocin(STZ)was used to prepare Diabetes Mellitus(DM)rat models and the unmodeled rats were eliminated.At the 22 nd week of modeling,the Morris water maze test was used to compare the escape latency and the number of platform crossings in each group of rats.Escape latency was prolonged,which implied that the learning ability of DM rats was impaired and the number of platform crossings increased,indicating that the memory of DM rats was impaired.The rat model of DE was selected from established DM rats and set to DE group.The remaining model rats were DM group.At the 24 th week of modeling,each group of rats was anesthetized,and intact rat hippocampus tissue was stripped and cryopreserved.At the same time,SD neonatal mice were removed within 24 hours of birth and intact hippocampal tissue was detached for isolation and culture of primary hippocampal neurons,and the specific marker microtubule-associated protein 2(MAP-2)was used.Cell identification.Human hippocampal neurons were incubated with different concentrations of H2O2,high glucose,and mannitol to establish a cell injury model.TargetScan software was used to screen possible mi RNAs related to DE.Real-time fluorescent quantitative PCR was used to detect target miRNAs in hippocampal tissue and primary hippocampal neuronal cell injury models in DE rats.Results: Six DM rats developed DE rats.The escape latency of each group was gradually shortened.On the first to second day,there was nostatistical difference in the escape latency between the rats in each group(P>0.05).On the first 3-5 days,the difference between the DE group and the CON group and the DM group.Statistically significant(P<0.05).Through the space exploration experiment on the 6th day,the distances between the rats in the CON group and the DM group and the DE rats across the platform were statistically significant(P<0.05).There was a downward trend in the number of crossing platforms between groups,but the difference was not statistically significant(P>0.05)(Fig 2).MAP-2 immunofluorescence staining of primary hippocampal neurons cultured on the 9th day revealed a large number of hippocampal neurons under the microscope.TargetScan software can be used to screen out 10 possible microRNAs related to DE,namely: miR-132,mi R-30,miR-138,miR-124,miR-128,miR-155,mi R-182,miR-103 miR-107,mi R-15.Real-time PCR was used to verify the target mi RNAs in hippocampal tissue and primary hippocampal neuronal cell injury model in DE rats.The results showed that the expression of miR-15 and miR-132 in tissues and cells were significantly decreased compared with the control group.Conclusion: Diabetic encephalopathy rats' learning and memory abilities decreased significantly,and cognitive function was significantly impaired.The expression of miR-15 b and miR-132 in hippocampal tissue and cells of diabetic encephalopathy rats were consistent and both decreased.The decreased expression of mi R-15 and mi R-132 may be involved in the molecular biology process of diabetic encephalopathy.