The Functional And Clinical Significance Of Platelet-derived MiR-103b Changes In Pre-diabetes

Objective: Studies have revealed that miR-103 b plays a critical role in regulating glucose homeostasis and insulin resistance.The circulating SFRP4(secreted frizzled-related protein 4)plays a role in inflammatory processes and could be a potential strong-risk biomarker of pre-diabetes.Recently,some studies revealed that platelets contain miRNAs and that miR-103 b is especially enriched in human platelets,but its regulatory mechanism remains unclear.The objective of this study was to investigate the regulatory relationships and changes of platelet-derived miR-103 b and its target gene SFRP4,and explore its clinical significance as a predictive potential biomarker for the early diagnosis of type 2 diabetes(DM2).Methods: The study included 61 subjects with pre-DM subjects(n=48),non-complicated diabetic subjects(NCDM,n=47),and 50 healthy subjects(Control)in our affiliated hospital from October 2014 to June 2016.Leukocyte-depleted platelets(LDPs)were prepared by MSCS immunomagnetic bead isolate system.Bioinformatic analysis and identification of miRNA targets were assessed using luciferase assays,quantitative real-time PCR and western blots in vitro.The changes in miR-103 b and SFRP4 mRNA and protein levels were identified in platelets from healthy and pre-/or-diabetic individuals by qRT-PCR and ELISA.The clinical relevance was measured by the Person analysis,and Person’s coefficient correlation was performed to evaluate the association of platelet miR-103 b with SFRP4 levels in pre-DM,NCDM patients and controls,respectively.Finally,the analysis of ROC curves was constructed and area under the curves(AUCs)was calculated.Results: miR-103 family members possess high conservatism during species evolution,in which,miR-103 b is located on the human chromosome 5q34.miR-103 b directly targeted the 3’-UTR of SFRP4 and negatively regulated its expression.miR-103 b was especially gradually decreased in platelet of pre-DM subjects compared to controls,and was also reduced in NCDM patients,and conversely,its target SFRP4 mRNA and protein levels were significantly increased in platelet of pre-DM and NCDM subjects.miR-103 b was significantly and negatively correlated with SFRP4 in either pre-DM subjects or NCDM patients.Furthermore,the area under the curve(AUC)and 95% Confidence Interval(CI)for the receiver-operating characteristic(ROC)analysis was 0.934(95% CI:0.856~0.983)and 0.901(95% CI:0.878~0.990).At a cutoff value of 1.794,the sensitivity was 90.0% and the specificity was 89.4 % in discriminating pre-DM subjects from healthy controls.Conclusion: The results revealed that platelet-derived miR-103 b had many characteristics and high diagnostic value for differentiating pre-DM subjects from healthy controls with a high sensitivity and specificity,indicating that miR-103 b is a potential biomarker for diagnosis pre-diabetes。...