ABSTRACT
OBJECTIVES: High expression levels (HELs) of microRNA-122 (miR-122) or microRNA-222 (miR-222) have been associated with insulin resistance (IR), which leads to the development of obesity. The association between HELs of circulating miR-122 and miR-222 and the risk of obesity was evaluated in Mexican school-aged children, where childhood obesity is the primary cause of morbidity. METHODS: Anthropometric data, biochemical parameters, and caloric intake were obtained in 50 children with obesity and 49 children with normal weight. The expression of circulating miR-122 and miR-222 was measured by quantitative real-time polymerase chain reaction amplification. Data were analyzed using Student t test, Pearson correlation coefficient, associations with chi-square, and multiple linear and logistic regressions with SPSS software v.23. RESULTS: The mean relative expression for miR-122 and miR-222 was 0.33 and 5.65, respectively, for children with obesity and 0.22 and 3.16, respectively, for children with normal weight. The expression of miR-122 and miR-222 was 1.47 and 1.78-fold higher, respectively, in children with obesity (P = 0.001 and P = 0.025). HELs of both miR-122 and miR-222 were associated with body mass index (BMI), waist to height ratio (WHR), fat percentage, serum high-density lipid levels, triglycerides (TGs), and metabolic index (MI) (P < .001). CONCLUSIONS: The HELs of circulating miR-122 conferred a 3.85-fold increase in the risk for obesity, whereas the HELs of both miR-122 and miR-222 conferred a 3.11-fold increase in the risk for obesity, which were also associated with higher anthropometric or biochemical parameters, such as BMI, WHR, fat percentage, serum high-density lipid levels, TGs, and MI, in Mayan children.
