We previously reported dysregulated expression of liver-derived messenger RNA (mRNA) and long noncoding RNA (lncRNA) in patients with advanced fibrosis resulting from nonalcoholic fatty liver disease (NAFLD). Here we sought to identify changes in mRNA and lncRNA levels associated with activation of hepatic stellate cells (HSCs), the predominant source of extracellular matrix production in the liver and key to NAFLD-related fibrogenesis. We performed expression profiling of mRNA and lncRNA from LX-2 cells, an immortalized human HSC cell line, treated to induce phenotypes resembling quiescent and myofibroblastic states. We identified 1964 mRNAs (1377 upregulated and 587 downregulated) and 1460 lncRNAs (665 upregulated and 795 downregulated) showing statistically significant evidence (FDR ≤0.05) for differential expression (fold change ≥|2|) between quiescent and activated states. Pathway analysis of differentially expressed genes showed enrichment for hepatic fibrosis (FDR = 1.35E-16), osteoarthritis (FDR = 1.47E-14), and axonal guidance signaling (FDR = 1.09E-09). We observed 127 lncRNAs/nearby mRNA pairs showing differential expression, the majority of which were dysregulated in the same direction. A comparison of differentially expressed transcripts in LX-2 cells with RNA-sequencing results from NAFLD patients with or without liver fibrosis revealed 1047 mRNAs and 91 lncRNAs shared between the two datasets, suggesting that some of the expression changes occurring during HSC activation can be observed in biopsied human tissue. These results identify lncRNA and mRNA expression patterns associated with activated human HSCs that appear to recapitulate human NAFLD fibrosis.
Keywords: Cirrhosis; Hepatic fibrosis; Hepatic stellate cells; Long noncoding RNA; Nonalcoholic fatty liver disease.
© 2020 The Author(s).