The Expression And Significance Of MicroRNA Let-7 In Maternally Peripheral Blood Of Severe Preeclampsia

Objective:Hypertensive disorder complicating pregnancy(HDCP) is a major cause of maternal mortality and morbidity. Preeclampsia(PE) belongs to the spectrum of hypertensive disorders complicating pregnancy and if lack of early diagnosis and/or timely treatment results in fatal consequences for both the mother and the baby. But recently, the pathogenesis is not clear yet. Therefore, the study on the pathogenesis of preeclampsia has very important clinical significance on improving the diagnosis and treatment. micro RNA is a kind of endogenous and non-coding small RNA, let-7 family belongs to micro RNA which regulates the gene expression in the transcriptional level. The studies on the association between let-7 family and preeclampsia are relatively rare. We investigate the expression levels of micro RNA let-7(including let-7a, let-7b, let-7g, let-7i) in peripheral white blood cells of severe preeclampsia(SPE) and normal pregnancy(NP) women, in order to analyze the potential association between the expression level of let-7 and PE, and provide the theoretical evidence for the pathogenesis of PE. Methods:Fresh peripheral blood of SPE and NP women were enrolled from October, 2015 to February, 2016 in the second hospital of Jilin university, and you need to refer to the clinical data of the patients and record. PE diagnostic criteria refers to the national unified textbook of the eighth edition of the obstetrics and gynecology. This experiment selected groups of patients were excluded history of pregnancy complications including cardiovascular disease, kidney disease, diabetes mellitus, acute or chronic infectious diseases and so on. Total RNA was extracted by mi Rcute mi RNA isolation kit, its concentration and purity was measured by spectrophotometer. Then total RNA was taken by reverse transcription test. U6 was selected as house-keeping gene. SYBR GreenⅠreal-time fluorescence quantitative PCR method was used to amplify let-7a, let-7b, let-7g, let-7i in micro RNA-let-7 family. The statistical software SPSS 21.0 and the 2-ΔΔCT relative quantitative method was used in data processing. Results:1、The let-7a, let-7b,let-7g,let-7i were expressed in the maternally peripheral blood between NP and SPE.2、Pearson and Spearman’s correlation analysis found that age and body mass index were not related to the expression level of let-7a, let-7b, let-7g, let-7i in peripheral white blood cells(P>0.05).3、The expression level of micro RNA let-7a, let-7g in peripheral white blood cells from SPE women were significantly different compared with that from NP women(P<0.05).4、The expression level of micro RNA let-7b, let-7i in peripheral white blood cells from SPE women were not significantly different compared with that from NP women(P>0.05). Conclusion:1 、 The SYBR Green I fluorescent quantitative real-time RT-PCR method combined with comparison of Ct values which quantitated the expression levels of let-7a, let-7b, let-7g, let-7i relative to the reference gene U6 was feasible, simple and specific.2、let-7a, let-7b, let-7g, let-7i were expressed in peripheral white blood cells between NP and SPE.3、The expression level of let-7a, let-7b, let-7g, let-7i may have no relationship with age and body mass index(BMI).4、The expression level of the let-7a, let-7g in peripheral white blood cells were associated with SPE, the further research need to be done.5、The expression level of the let-7b, let-7i in peripheral white blood cells were not associated with SPE.