The Altered Expression And Significance Of Serum MiRNA-222 In Polycystic Ovary Syndrome Patients With Hyperinsulinemia

Background Polycystic ovary syndrome(PCOS)is the most common endocrine metabolicdisorder in women of reproductive age with the main clinical feature: polycysticovary,oligomenorrhea or amenorrhea,infertility,obesity.Hyperandrogenism,insulin resistance(IR),hyperinsulinemia(HH)is the endocrine feature.In addition,PCOS is related to some complications,such as diabetes,cardiovascular disease,and endometrial lesions,metabolic syndrome,which would influence the long-term life quality of PCOS patients.IR is the main endocrine features of PCOS,it may be involved in the long-term complications,especially the occurrence of diabetes.Micro RNA(mi RNA)is a kind of non-coding RNA that are able to regulate gene expression at the post-transcriptional level.Researches have shown that mi RNA is involved in follicular development and steroid hormone metabolism,and its expression level in PCOS is associated with the specificity of organ,tissue and disease,which suggesting mi RNA may participate in the pathophysiological process of PCOS.Recent studies have found that mi RNA steadily exists in peripheral blood and various kinds of body fluids,its expression level is closely related to disease,shows the peripheral blood mi RNA might serve as the potential biomarker of disease diagnosis,treatment and prognosis.Objective To investigate the altered expression of serum mi RNA-222 in polycystic ovary syndrome patients having hyperinsulinemia and the influence of oral metformin on the expression of mi RNA-222,and explore the correlation between mi RNA-222 and PCOS and insulin resistance.Methods Using real-time quantitative PCR to investigate the expression of serum mi RNA-222 between PCOS patients having hyperinsulinemia(n=30)and age,BMI matched normal women(control group,n = 30).Using correlational analysis method to discuss the relationship between mi RNA-222 and clinical and biochemical markers of PCOS;Investigate the expression of serum mi RNA-222 before and after treatment with oral metformin(500mg,tid,4 weeks)of PCOS group(n=17).Result The relative expression of mi R-222 was significantly upregulated in PCOS group(P<0.05).A positive correlation was found between mi R-222 and serum insulin(R2=0.7462,P<0.001),the area under the receiver operating characteristic(ROC)curve(AUC)is 0.703.The relative expression of mi R-222 is significantly downregulated after treatment with oral metformin(P<0.05).Conclusion The relative expression of mi R-222 was significantly upregulated in PCOS patients with hyperinsulinemia,and was positively correlated with the level of serum insulin.Metformin decreased the expression of serum mi RNA-222.Serum mi RNA-222 may be involved in the pathophysiological process of PCOS and IR.Significance This study showed that the expression level of serum mi RNA-222 significantly increased in patients with PCOS having hyperinsulinemia,prompting serum can be used as PCOS related mi RNA research source.Compared with tissue,serum mi RNA is easy to get or detect,and more practical.This study also showed that the expression of serum mi RNA-222 is closely associated with insulin level,implying serum mi RNA-222 may participate in insulin and glucose metabolism.Mi RNA-222 could serve as a new biomarker in diagnosis,treatment,evaluating prognosis of PCOS.