Genome-wide analysis of long noncoding RNA expression profiles in patients with non-alcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) is a common liver disorder poising burgeoning health problem to humans. Recent studies have shown that long non-coding RNA (lncRNA) plays critical roles in a myriad of biological processes and human diseases. Since the roles of lncRNA in NAFLD remain unknown, they were investigated in the study. Microarray expression profiling of mRNAs and lncRNAs was conducted using RNA extracted from patients with and without NAFLD. One thousand seven hundred thirty-five lncRNAs and 1485 mRNA were found differentially expressed in NAFLD samples compared with those in control samples. Among them 535 and 1,200 lncRNAs were upregulated and downregulated in NAFLD, respectively; 760 and 725 mRNAs were upregulated and downregulated in NAFLD, respectively. Moreover, seven lncRNAs and seven mRNAs that were highly up- or downregulated in NAFLD samples were validated by quantitative real-time polymer chain reactions. Kyoto Encyclopedia of Genes and Genomes pathway analysis and Gene Ontology analysis for the differentially expressed mRNAs showed that these RNAs are involved in various metabolic processes, cellular components, and molecular functions. Our findings indicate that the expression profiles of lncRNAs have changed in NAFLD as compared with normal liver, and the identified regulated RNAs may provide novel insight into the molecular mechanisms underlying the disease and potential novel diagnostic or therapeutic targets for NAFLD.