Abstract: Objective  To detect the expression of RNA2213p (miR2213p) in patients with severe depression, analyze its clinical significance, and explore the relationship between miR2213p and brainderived neurotrophic factor(BDNF), human neurotrophic factor4(NT4), S100B protein(S100B) and superoxide dismutase(SOD), respectively. And to explore the expression consistency of miR2213p in cerebrospinal fluid and serum. Methods  A total of 59 patients with severe depression were selected as observation group and normal serum samples were taken. Totally 59 serum samples of normal adults were taken as control group. MiR2213p was detected by realtime fluorescence quantitative PCR(qPCR) in two groups. The expressions of BDNF and S100B were detected by ELISA method in observation group, SOD was detected by xanthine oxidase method in serum, and NT4 was detected by Western Blot method in the serum. MiR2213p was detected in cerebrospinal fluid which was extracted from 39 patients with severe depression. Results  There was statistically significance in the difference of MiR2213p of  two groups (P<0.05).  miR2213p in the groups divided by family history of mental disorders also showed  significant difference(P<0.05). Negative correlation was found between miR2213p and BDNF(r=-0.51, P=0.036), miR2213p and SOD (r=-0.57, P=0.013), miR2213p and NT4(r=-0.62, P=0.009). miR2213p and S100B had positive correlation(r=0.59, P=0.014). Positive correlation of miR2213p  existed between serum and cerebrospinal fluid(r=0.72, P=0.001). Conclusion  Abnormal expression of serum miR2213p affects the formation and progression of severe depression. MiR2213p may play a role in regulating neurotrophic factors, injury factors and stress indicators. There is expression consistency of miR2213p in the serum and cerebrospinal fluid.

Key words: depressive disorder, mir2213p, brainderived neurotrophic factor, s100 proteins, superoxide dismutase, peripheral blood, cerebrospinal fluid