MicroRNA 122 Reflects Liver Injury in Children with Intestinal Failure-Associated Liver Disease Treated with Intravenous Fish Oil

Abstract

Background: There is evidence that microRNA (MIR) 122 is a biomarker for various liver diseases in adults and children. To date, MIR122 has not been explored in children with intestinal failure-associated liver disease (IFALD, or hyperbilirubinemia associated with prolonged parenteral nutrition).

Objectives: This study's purpose was to investigate changes in plasma miR-122, correlate miR-122 with serum liver function tests and enzymes, and investigate changes in whole blood transcripts including miR-122 targets in a group of children with IFALD who received pure intravenous fish oil (FO) as a treatment for cholestasis.

Methods: This was a prospective, observational study that enrolled children with IFALD who received intravenous FO (1 g/kg/d) and whose cholestasis resolved with FO. Plasma miR-122 was measured using reverse transcription-quantitative real-time PCR, and whole blood miR-122 targets were quantified using RNA sequencing.

Results: Fourteen subjects with median age 6 mo (IQR: 3-65 mo) were enrolled. RNA sequence data were available for 4 subjects. When compared with the start of FO, median miR-122 concentrations at 6 mo of FO therapy decreased [1.0 (IQR: 1.0-1.0) compared with 0.04 (IQR: 0.01-0.6), P = 0.009]. At the start of FO, miR-122 correlated with conjugated bilirubin (r = 0.56; P = 0.038). At ∼3 mo of FO, miR-122 correlated with conjugated bilirubin (r = 0.56; P = 0.045). Reactive oxygen species, heme metabolism, coagulation, adipogenesis, IL-6-Janus kinase-signal transducer and activator of transcription (JAK-STAT) 3, IL-2-STAT5, transforming growth factor-β, TNF-α, inflammatory response, mammalian target of rapamycin gene families (normalized enrichment scores < -1.4), and miR-122 target genes were significantly downregulated with FO.

Conclusions: In this small cohort of young children with IFALD, miR-122 decreased with FO therapy and correlated with conjugated bilirubin. Key pathways involving oxidation, inflammation, cellular differentiation, and nutrient regulation were downregulated. Data from this study provide information about IFALD and FO. This trial was registered at www.clinicaltrials.gov as NCT00969332.

Copyright © The Author(s) 2020.

Figures

FIGURE 1

Volcano plot showing the distribution of transcripts by comparing the log2-fold change in gene expression between baseline and 6 mo of fish oil treatment in 4 children with intestinal failure–associated liver disease. White and black circles represent significant decrease or increase in expression, respectively. Genes with no change are highlighted in gray. The x-axis represents log2-fold change in expression, and the y-axis represents negative log10 value of the false discovery rate (FDR). Genes with a log2-fold change value ≥1 and FDR value <0.05 are considered significant.

FIGURE 2

Heat maps for 4 children (refered to as p1 to p4) with intestinal failure–associated liver disease before and after 6 mo of treatment with fish oil. Heatmaps show the abundance of circulating blood mRNA/transcript associated with: (A) adipogenesis, mammalian target of rapamycin complex (mTORC)-1 signaling, and reactive oxygen species (ROS) pathways, and (B) IL-6-Janus kinase–signal transducer and activator of transcription (JAK-STAT) 3 pathway, IL2-STAT5 pathway, inflammatory pathway, and transforming growth factor (TGF)-β signaling and TNFα pathways. p refers to patient. Scale bar represents the mean-centered log2-normalized counts (row z-score) and is represented by the red to blue vertical bar scaled 3 to -1.

Figure 3

Heat maps in four children (p1, p2, p3, p4) with intestinal failure associated liver disease before and after 6 mo of fish oil (FO) treatment. Heatmaps show the abundance of miR-122 targets in the whole blood. Scale bar represents the mean-centered log2-normalized counts (row Z score) and is represented by the red to blue vertical bar 1.5 to -1.