Study On The Relationship Between MiR-34b/c And Cognitive Function Of Depressive Disorder

Objective: To explore the effect of inordinately expression and genetic susceptibility of mi R-34b/c on cognitive impairment in depressive disorder.Methods: According to a case-control study design, study on inordinately expression recruited 60 patients with depressive disorder and 60 normal controls, then detected the level of mi R-34b/c expression, and analyzed the correlation between mi R-34b/c expression and cognitive function in patients and normal controls, genetic susceptibility study recruited 500 patients with depressive disorder and 300 normal controls, then tested their mi R-34b/c gene polymorphisms, and analyzed the association between mi R-34b/c gene polymorphisms and cognitive function in patients with depressive disorder. The repeatable battery for the assessment of neuropsychological status, Stroop Color Test, trail making test, Wisconsin Card Sorting Test were used to evaluated the cognitive function. The statistical methods we used were Independent sample t test, chi-square test and ANOVA analysis. In the ANOVA analysis, expression or genotype and diagnosis(patients vs. controls) were entered as fixed factors, scores of all cognitive tests were entered as dependent variables and demographic factors including age, gender, education years were treated as covariates.Results: 1. Mi R-34 c expression was significantly increased in the case group(t=2.015,P=0.046). There was no difference in the expression of mi R-34 b between the case and control group(t=1.370,P=0.173).The main effect of mi R-34 c expression was significant for immediate memory(F=5.129,P=0.028), delayed memory(F=4.270,P=0.044), the time for trail making test A(F=7.164,P=0.010). The interactions between diagnosis and mi R-34 c expression were significant for delayed memory(F=4.157,P=0.047), the time for trail making test A(F=4.045,P=0.050), the time for trail making test B(F=4.550,P=0.038). The main effect of mi R-34 b expression was significant for total number of words(F=4.914,P=0.033). The interactions between diagnosis and mi R-34 b expression were significant for the time for trail making test B(F=4.244,P=0.046). 2. The interactions between diagnosis and rs4938723 genotype were significant for the complete classification number(F=4.921,P=0.027), the number of response errors(F=3.943,P=0.047). The interactions between diagnosis and rs2187473 genotype were significant for immediate memory(F=4.320,P=0.038), the time for reading font-color(F=4.684,P=0.031) and time for eliminating the interference of word(F=3.890, P=0.049). The main effect of rs28757623 genotype was significant for complete classification number(F=3.973,P =0.047), the number of correct responses(F=8.765,P=0.003), the number of response errors(F=7.479,P=0.006), the rate of conceptualization level(F=14.123,P=0.000). No significant interactions between diagnosis and rs28757623 genotype were found temporarily.Conclusion: The abnormal expression of mi R-34 c in peripheral blood was found in patients with depressive disorder, and the abnormal expression of mi R-34b/c might be related to the cognitive function of the patients with depressive disorder. Mi R-34b/c genetic susceptibility might be associated with cognitive function of the patients with depressive disorder.