The investigation of circulating microRNAs associated with lipid metabolism in childhood obesity

Background: Childhood obesity is an increasing health challenge related to increased risk of chronic diseases. microRNAs (miRNAs) are noncoding short RNA molecules regulating multiple biological processes linked to obesity. Objectives: We aimed at evaluating the association between circulating miRNA levels and lipid metabolism in obese and non-obese children and adolescents. Methods: By constituting study group, 45 obese children and adolescents were recruited. To perform comparisons with study group, 41 lean controls were matched for age and sex. Using real-time quantitative PCR analysis, circulating miRNAs were evaluated in both groups. Results: Circulating miR-335 (P < 0.001), miR-143 (P = 0.001) and miR-758 (P = 0.006) in obese children were significantly lower than those of controls. However, circulating miR-27 (P = 0.032), miR-378 (P < 0.001) and miR-370 (P = 0.045) in obese children were significantly higher, compared with those of controls. In addition, circulating miR-33 in obese children was higher than those of controls, but no significant difference was present (P = 0.687). Conclusion: Our findings showed that a significant association is present between circulating miR-370, miR-33, miR-378, miR-27, miR-335, miR-143 and miR-758 values, and childhood obesity. Low levels of miR-335, miR-143 and miR-758, and high levels of miR-27, miR-378, miR-33 and miR-370 may have been responsible for elevated triglycerides and low-density lipoprotein (LDL-C) levels, and low level of high-density lipoprotein (HDL-C) in obese subjects. Therefore, miRNAs may be a good novel biomarker for childhood obesity.