Noninvasive techniques for evaluating the severity of
nonalcoholic fatty liver disease (
NAFLD) have shown limited diagnostic performance.
MicroRNAs (
miRNAs) are useful
biomarkers for diagnosing and monitoring the progression and treatment response to several diseases. Here, we evaluated whether serum exosomal
miRNAs could be used for the diagnosis and prognosis of
NAFLD severity. Exosomal
miRNAs were isolated from the sera of 41 patients with
NAFLD (diagnosed using liver biopsy) for microarray profiling. The degree of
NAFLD severity was determined using
inflammation, steatosis, and ballooning scores and the
NAFLD activity score (
NAS). Correlations between
miRNA expression, clinical and biochemical parameters, and
mRNA expression were analyzed. Overall, 25, 11, 13, and 14
miRNAs correlated with the
inflammation score, steatosis score, ballooning score, and
NAS, respectively, with 33 significant correlations observed between 27
miRNAs and six clinical variables. Eight
miRNAs (let-7b-5p, miR-378h, -1184, -3613-3p, -877-5p, -602, -133b, and 509-3p) showed anticorrelated patterns with the corresponding
mRNA expression. In
fibrosis, 52 and 30 interactions corresponding to high
miRNA-low
mRNA and low
miRNA-high
mRNA expression, respectively, were observed. The present results therefore suggest that serum exosomal
miRNAs can be used to evaluate
NAFLD severity and identify potential targets for
NAFLD treatment.