Background: Obesity is a major public health problem and its rate is increasing worldwide. Obesity accompanies perturbations in metabolism, conferring substantial excess risk for insulin resistance and Type 2 diabetes. Various genetic and epigenetic factors contribute to the development of obesity. MicroRNAs (miRNAs) are short noncoding RNAs involved in posttranscriptional regulation of gene expression and influence many cellular functions including glucose and lipid metabolism and adipocyte differentiation. miRNAs have been shown to be involved in obesity but their role in this regard is not clearly defined.
Objective and hypotheses: The aim of this study was to evaluate the levels of miR-34a and miR-149 and their association with metabolic parameters in obese children and adolescents.
Method: Seventy children (35 obese and 35 control) (818 years) were included in the study. The miRNA fractions were isolated from plasma and elongated by poly A tailing using E. Coli poly A polymerase. The resulting miRNA was reverse transcribed into cDNA, amplificated by Real time PCR using miRNA-specific primers and detected by SYBR green. Data were normalized with cel-miR-39 and compared with ΔΔCt method. Concentrations of visfatin and insulin in plasma were measured by ELISA method. Glucose and lipid profile were determined colourimetrically. HOMA-IR was calculated and used as an index of insulin resistance.
Results: There was an inverse relationship between miR-34a levels and both insulin and HOMA-IR. On the other hand, miR-149 was significantly correlated with visfatin. There was no significant difference in miR-34a and miR-149 between obese and normal weight subjects. Visfatin was significantly elevated in obese children compared to control subjects and was correlated with glucose, insulin and HOMA-IR.
Conclusion: miR-34a is associated with insulin and HOMA-IR and thus seems to be involved in insulin resistance. miR-149 is inversely associated with visfatin levels which could be indicative of anti-inflammatory effect of this miRNA.
10 - 12 Sep 2016
European Society for Paediatric Endocrinology