Effects Of MiR-155-5p On The Behavior Of VPA Autistic Mice And Its Mechanism

Objective: To explore the effect of miR-155-5p on the behavior of valproic acid(VPA)autistic mice and its mechanism,so as to provide a new research direction for the treatment of autism.Methods: Male and female C57 mice were caged overnight in 2:1 ratio,and recorded as E1 days after Yin suppository was seen.They were raised separately in cages.Pregnant female rats were randomly divided into two groups: one group was treated with VPA of 600 mg / kg prepared by intraperitoneal injection of normal saline on day E12.5 as the model group,and the other group was treated with the same amount of normal saline on day E12.5 as the control group.The offspring of female rats in the model group were VPA model rats(VPA group),while the offspring of female rats in the control group were recorded as normal control group(Na Cl group).The VPA mice of the first generation were randomly divided into two groups: one group was injected with mir-155-5p antagomir and the other group was injected with NC antagomir;the other group was also randomly divided into two groups: one group was injected with mir-155-5p antagomir and the other group was injected with NC antagomir.Finally,it is divided into the following four groups: VPA + mir-155-5p antagomir group,VPA + NC group,Na Cl + mir-155-5p antagomir group and Na Cl + NC group.Three boxes of social experiment,open field experiment and animal behavior test and analysis of standing times were carried out in 1,2,3 and 4 weeks after nasal drip of the four groups of mice.The most significant time point was two weeks after nasal drip.RNA and protein were extracted from mouse prefrontal cortex two weeks after nasal drip.The expression of mir-155-5p in each group was detected by real-time fluorescence quantitative PCR,and the target gene regulated by mir-155-5p was screened out.The protein expression level of the target gene was detected by immunoblotting.Results: The results of behavioral experiment showed that the best detection time was 2W after nose dropping.Compared with VPA + NC group,the interaction time between VPA + mir-155-5p antagomir group and unfamiliar mice increased significantly in three boxes of social experiment detection,the number of crossing the middle square in open field experiment detection and the number of upright body detection also increased significantly.The results of real-time fluorescent quantitative PCR showed that VPA + mir-155-5p There was no significant difference in mir-155-5p relative quantity between the two groups(P > 0.05).The target gene inducible nitric oxide synthetase(inducible nitric oxide synthetase)of mir-155-5p was screened out Western blot was used to detect the expression of NOS2 protein.The results showed that the level of NOS2 protein in VPA + mir-155-5p antigomir group was significantly lower than that in VPA + NC group(P < 0.05),and the level of NOS2 protein in VPA + NC group was significantly higher than that in Na Cl + NC group(P < 0.05).Conclusions: miR-155-5p in prefrontal cortex(PFC)of VPA autistic mice treated with mir-155-5p antagomir nose drops significantly decreased,and their social ability and ability to explore new things have been improved,which may be related to the decreased expression of NOS2,suggesting that mir-155-5p may be a new target of autistic treatment.