Circulating microRNA-223 as a potential biomarker for obesity

Obesity is a serious health problem that is implicated in many metabolic disorders. Recent studies have proposed that microRNA-223 (miR-223) is a potent regulator of many diseases related to obesity. However, the association of miR-223 with obesity remains unclear. In this study, we examined the relationship between serum miR-223 and obesity.

A total of 121 subjects were selected, including 41 normal-weight, 40 overweight and 40 obesity subjects. The overweight and obesity subjects received lifestyle intervention for 3 months after baseline examination. Quantitative real-time PCR was used to measure the expression of circulating miR-223 in the serum.

MiR-223 was lower in both overweight and obesity subjects compared with normal-weight control (1.06 vs. 7.54, p<0.001; 4.56 vs. 7.54, p<0.001, respectively). Circulating miR-223 increased significantly in both overweight and obesity groups after lifestyle intervention. Furthermore, subjects with the lowest tertile of miR-223 expression had the highest obesity prevalence. The odds ratio was 2.77 (95% confidence interval: 1.59-6.54, p<0.05) compared with the highest tertile of miR-223 expression. Such association was still apparent after adjusting for other major risk factors.

The findings in this study suggest that miR-223 is a factor of obesity. The level of miR-223 in the serum can be used as a biomarker of obesity and therapeutic response.