[Screening of specific microRNA in hippocampus of depression model rats and intervention effect of Chaihu Shugan San].

Objective: To screen microRNAs with specific expression of in hippocampus of rats with chronic stress induced depression model, and observe the effect of traditional Chinese medicine Chaihu Shugan San on the expression of microRNA in hippocampus.

Method: SD rats were randomly divided into 3 groups: the normal control group, the model control group and the Chaihu Shugan San group. The depression model was replicated by unpredictable chronic mild stress combined with separation. Behavioral changes of the rats were observed by Open-field test and sucrose solution consumption test, and the expression of microRNAs in hippocampus was assayed by microRNA micro-array.

Result: Compared with the normal control group, there were 13 specific miRNAs in hippocampus in the model control group with the expression difference of more than 2 times. Among them, down-regulating miRNAs included miR298, miR-130b, miR-135a, miR-323, miR-503, miR-15b, miR-532, and miR-125a, and the up-regulation miRNAs included miR7a, miR-212, miR-124, miR-139, and miR-182. Among the 13 specific miRNAs, miR-125a and miR-182 recovered to normal after intervention with Chaihu Shugan San in the Chaihu Shugan San group.

Conclusion: This study preliminarily found that 13 specific miRNAs in hippocampus are related to depression. Among them, miR-125a and miR-182 recover to normal after intervention with Chaihu Shugan San, which may be the target points of the antidepressant effect of Chaihu Shugan San. We shall further analyze the target genes and their mechanisms.