Circulating microRNA‑135a‑3p in serum extracellular vesicles as a potential biological marker of non‑alcoholic fatty liver disease

Abstract

Non-alcoholic fatty liver disease (NAFLD) is a widespread threat to human health. However, the present screening methods for NAFLD are time-consuming or invasive. The present study aimed to assess the potential of microRNAs (miRNAs/miRs) in serum extracellular vesicles (EVs) as a biomarker of NAFLD. C57BL/6J mice were fed either a 12-week high-fat diet (HFD) or standard chow to establish NAFLD and control groups, respectively. Serum samples were obtained from the mouse model of NAFLD, as well as 50 patients with NAFLD and 50 healthy individuals, and EVs were extracted and verified. Using reverse transcription-quantitative PCR, the mRNA expression level of selected miRNAs in the serum and EVs was analyzed. In order to determine the diagnostic value, receiver operating characteristic (ROC) curves were used. The mice treated with HFD showed notable hepatic steatosis and higher concentrations of serum alanine aminotransferase (ALT). There was also a significant decrease in the expression levels of miR-135a-3p, miR-129b-5p and miR-504-3p, and an increase in miR-122-5p expression levels in circulating EVs in mice treated with HFD and patients with NAFLD. There were also similar miR-135a-3p and miR-122-5p expression patterns in the serum. ROC analysis demonstrated that miR-135a-3p in circulating EVs was highly accurate in diagnosing NAFLD, with the area under the curve value being 0.849 (95% CI, 0.777-0.921; P<0.0001). Bioinformatics analysis indicated that dysregulated miR-135a-3p was associated with 'platelet-derived growth factor receptor signaling pathway' and 'AMP-activated protein kinase signaling pathway'. In summary, circulating miR-135a-3p in EVs may serve as a potential non-invasive biomarker to diagnose NAFLD. This miRNA was a more sensitive and specific biological marker for NAFLD compared with ALT.

Selective Isolation of Liver-Derived Extracellular Vesicles Redefines Performance of miRNA Biomarkers for Non-Alcoholic Fatty Liver Disease

“…Jiang et al [ 39 ] recently reported that, compared with total serum-derived miRNA, differences in EV-derived miRNAs, including miR-122 (ROC = 0.79), more effectively discriminated subjects with NAFLD from healthy controls. In contrast with Jiang, et al [ 39 ], in the current study isolation of global EVs did not improve the predictive performance of miRNA biomarkers with respect to identifying individuals with NAFLD.…”

“…Jiang et al [ 39 ] recently reported that, compared with total serum-derived miRNA, differences in EV-derived miRNAs, including miR-122 (ROC = 0.79), more effectively discriminated subjects with NAFLD from healthy controls. In contrast with Jiang, et al [ 39 ], in the current study isolation of global EVs did not improve the predictive performance of miRNA biomarkers with respect to identifying individuals with NAFLD. It is plausible that differences in performance gains achieved by global EV isolation relate to differences in the composition of the NAFLD cohort (i.e., the proportion of individuals with NAFL versus NASH or the proportion of individuals with non-hepatic co-morbidities).…”

Clinical and Molecular Biomarkers for Diagnosis and Staging of NAFLD

“…Another study reported that miR-181d, -99a, -197 and -146b expression levels were lower in NAFL subjects with respect to controls; furthermore, miR-197 and -146b levels negatively correlated with inflammation grade, while miR-181d and -99a levels were inversely associated with GGT in NASH patients [ 89 ]. Finally, recent studies reported that miR-29, -1296, -132 and -135 were deregulated in NAFL patients and correlated with the risk of disease onset [ 90 , 91 , 92 , 93 , 94 ]. Only one study, instead, evaluated lncRNAs as an NAFL biomarker.…”

Extracellular Vesicles in Non-alcoholic Fatty Liver Disease and Alcoholic Liver Disease

“…In addition, different EVs contents at different stages can be used as biomarkers and non-invasive diagnostic tools. For instance, circulating miR-135a-3p in serum EVs serve as potential biomarkers of NAFLD ( Jiang et al, 2021 ).…”