| BackgroundMicroRNA (miRNA) is a recently discovered class size of about19to24nucleotides single-stranded small molecule RNA.They mainly target genetranscription by the mRNA with partially or completely complementary paircombination of post-transcriptional level to regulate the expression of target genes.Several studies have shown that miRNAs show specific expression and play animportant role in the process of cardiovascular, infection, tumor and diabetes mellitus.KongLetal. chose seven miRNAs through literature retrieval,and measured theirexpression level in serum from pre-diabetes mellitus and newly-diagnosised T2DMpatients,the results showed that the expression of miR-9, miR-29a, miR-34a,miR-146a, miR-375in newly-diagnosised T2DM patients were higher than thehealthy controls and pre-diabetes group. ZampetakiA etal. discovered miRNA-15a,miRNA-29b,miRNA-126,miRNA-223downregulated and miRNA-28-3Pupregulatedin the early stage of T2DM by microarray scanning and quantitative PCR. Peiying Letal.found that the relative expression level of plasma miRNA–126in simple T2DMgroup and T2DM with macroangiopathy group were significantly lower. However,miRNA-126is specifically expressed in endothelial cells.Studies about the relationship between miRNA-126expression changes and plasma endothelial nitricoxide synthase(eNOS),glucose and lipid metabolism and islet function in T2DMpatients are rare. This study based on detecting the changes of plasma miRNA-126levels in different stages of patients with T2DM to analyze the relationship betweenmiRNA-126expression level and eNOS,glucose and lipid metabolism and isletfunction.ObjectiveTo investigate the clinical significance of miRNA-126expression level inperipheral plasma from pre-diabetes mellitus,simple T2DM,T2DM withmacroangiopathy and T2DM with macroangiopathy,microangiopathy patients. Toanalyze the relationship between miRNA-126expression level and eNOS and glucoseand lipid metabolism and islet function.MethodsThe plasma miRNA-126expression level was measured using real-time PCR(RT-PCR);The plasma endothelial nitric oxide synthase(eNOS)was measured withenzyme-linked immunosorbent assay(ELISA);Plasma glucose was measured withglucose oxidase method; Hemoglobin A1c(HbA1c)was measured with highperformance liquid chromatography;Fasting insulin(FIns) was measured withChemiluminescent microparticle immunoassay;Triglycerides(TG),total cholesterol(TC), high-density lipoprotein cholesterol(HDL-C) and low density lipoproteincholesterol (LDL-C)were measured by fully automatic biochemical analyzer. One-way analysis of variance was used to compare the miRNA-126level in the aboveconditions. The relationship between miRNA-126expression level and eNOS andother metabolic indices was analyzed. Results1.Compared with healthy controls, the plasma miRNA–126and eNOS levelin pre-diabetes group, simple T2DM group, T2DM with macroangiopathy group andT2DM with macroangiopathy, microangiopathy group were significantly lower（P<0.05); Similarly,compared with pre-diabetes group, miRNA-126and eNOS inT2DM with macroangipathy group and T2DM with macroangiopathy,microangiopathy group were significantly lower (P<0.05); Compared with simpleT2DM group, miRNA-126and eNOS inT2DM with macroangipathy group andT2DM with macroangiopathy,microangiopathy group were significantly lower(P<0.05); However there was no significant difference between the pre-diabetesgroup and simple T2DM group (P>0.05); Similarly, there was no significantdifference between T2DM with macroangiopathy group and T2DM withmacroangiopathy, microangiopathy group(P>0.05).2.There were positive correlations between miRNA-126and LDL-C,DBP andeNOS (P<0.05);There were negative correlations between miRNA-126andFPG,HbA1c, HDL-Cand age(P<0.05). There was no significant correlation betweenmiRNA-126andbody mass index (BMI）, FIns, TG, TC, Systolic blood pressur（eSBP）,two-hour postprandial plasma glucose（2hPG）, homeostasis model assessment of isletbeta cell function index（HOMA-IS）and homeostasis model assessment of insulinresistance（HOMA-IR）(P>0.05).3.Multiple stepwise regression analysis result shows that FPG (β=-0.159, P <0.01), age (β=-0.030, P <0.01), LDL-C (β=0.208, P=0.037) and eNOS（β=0.353,P<0.01）were plasma miRNA-126independent impact factors.ConclusionCirculating miR-126level was decreased in patients with pre-diabetes andsimple T2DM and those with vasculopathy. FPG, age, LDL-C and eNOS were theindependent affecting factors of the miRNA-126, Speculating that endothelial cellspecific expression miRNA-126may be in the control of blood glucose and lipid metabolism,the decline of miRNA-126may be related to vascular endothelialdysfunction.This may serve as a significant toll to predict the occurrence of T2DMand its vascular lesions. |
PDF Full Text Request