Effect Of Curcumin On Hippocampal Neurons And Astrocytes In Autistic Rat Model

Objective: To study the effects of early intervention of curcumin on behavior and hippocampal DG,CA3 neurons and astrocytes in autistic model rats.Methods: According to the method of Schneider,Wistar rats were intraperitoneally injected with sodium valproate at 12.5 days of pregnancy,and the offspring were labeled as sodium valproate(VPA group).The control group was intraperitoneally injected with the same dose of normal saline,and the rats that were given were the saline group(NS group).The two groups of rats were identified by model.The morphological changes of hippocampal neurons in the two groups were observed by Nissl staining.The changes of neurons and astrocytes in hippocampus DG and CA3 were detected by immunofluorescence and image analysis techniques.A total of 100 7-day-old autistic model rats were randomly selected,of which 50 were randomly selected as the curcumin group(VPA-Cur group),50 were used as the solvent control group(VPA-C group),and 50 in the NS group were randomly selected as normal control group.In the VPA-Cur group,curcumin was injected intraperitoneally for 3 weeks at 7-old day after birth at a dose of 50 mg/kg(curcumin was formulated into a 10 mg/ml solution in PBS containing 0.1% DMSO),VPA-C group and NS group were given equal amounts of 0.1% DMSO in PBS.To observe the effect of early intervention of curcumin on the behavior of autistic rats,and detect the changes of neurons and astrocytes in hippocampus DG and CA3 by immunofluorescence and image analysis techniques on the 28 th day.Results: Compared with the NS group,the VPA-C group had the following abnormalities: in terms of development,compared with the NS group,the VPA-C rats showed significant weight loss,increased brain weight,and tail had 1~2 bending or tail length shortening,blinking time delay,direction directional abnormality,etc.;behavioral aspects,VPA-C group showed reduced social interaction and communication times,increased repetitive behaviors,and decreased learning and memory abilities.The number of neurons in DG and CA3 of hippocampus of 28-day-old VPA-C group were significantly lower than that of NS group(p <0.05),and the number of astrocytes were significantly higher than that of NS group(p <0.05).VPA-Cur group could significantly improve the abnormal development and behavioral disorders of autistic model rats,increased the number of social communication and interaction behaviors(p <0.05),improved learning and memory abilities(p <0.05);the number of neurons in hippocampus DG and CA3 of 28-day-old VPA-Cur group were significantly higher than that in VPA-C group and lower than that in NS group(p <0.05).The number of astrocytes in hippocampus DG and CA3 of 28-day-old VPA-Cur group was significantly lower than that of VPA-C group and higher than NS group(p <0.05).Conclusion: The expression of neurons in DG and CA3 areas of hippocampus in autism model rats were decreased,and the expression of astrocytes were increased;early intervention of curcumin could improve the abnormal development and behavior of autistic model rats;early intervention of curcumin could up-regulate the expression of neurons in hippocampal DG and CA3 regions of autistic model rats,and down-regulate the expression of astrocytes.