Evaluation of capillary miR-122 as a prognostic biomarker of paracetamol-induced liver toxicity.

INTRODUCTION: Paracetamol (acetaminophen) overdose is a leading cause of acute liver failure in many Western countries. Diagnostic tools for this poisoning may be suboptimal in some cases and new biomarkers have been investigated. We investigated the role of capillary microRNA-122 (miR-122) as a prognostic biomarker of liver injury in the clinical management of patients with paracetamol overdose. METHODS: In a paracetamol overdose patient cohort, miR-122 was measured by quantitative polymerase chain reaction in a blood drop obtained by a finger prick at the end of an antidote cycle treatment with N-acetylcysteine treatment (12 h). Liver injury was defined as serum alanine aminotransferase (ALT) activity > 100 IU/L collected at 10 or 20 h after the start of treatment. Pearson's correlation analyses were performed. RESULTS: In patients with paracetamol overdose, capillary miR-122 was positively correlated with ALT measured at 10 h and at 20 h (r = 0.83, P < 0.0001; r = 0.96, P < 0.0001, respectively). CONCLUSION: This work supports the potential use of capillary miR-122 as a prognostic biomarker of liver injury throughout clinical management of patients with paracetamol overdose. Capillary miR-122 can be measured in a blood drop collected by a finger prick, a minimally invasive diagnostic test for patient stratification.

Ethical challenges for pediatric liver organoid transplantation.

Liver organoid transplantation may be a less invasive alternative to liver transplant, but is it ethically acceptable to include children with liver disease in a first-in-human clinical trial of this new intervention?

Characterization of Triptolide-Induced Hepatotoxicity by Imaging and Transcriptomics in a Novel Zebrafish Model.

Triptolide is a vine extract used in traditional Chinese medicines and associated with hepatotoxicity. In vitro data suggest that inhibition of RNA synthesis may be the mechanism of toxicity. For studying drug-induced liver injury the zebrafish has experimental, practical and financial advantages compared with rodents. The aim of this study was to explore the mechanism of triptolide toxicity using zebrafish as the model system. The effect of triptolide exposure on zebrafish larvae was determined with regard to mortality, histology, expression of liver specific microRNA-122 and liver volume. Fluorescent microscopy was used to track toxicity in the Tg(-2.8lfabp:GFP)as3 zebrafish line. Informed by microscopy, RNA-sequencing was used to explore the mechanism of toxicity. Triptolide exposure resulted in dose-dependent mortality, a reduction in the number of copies of microRNA-122 per larva, hepatocyte vacuolation, disarray and oncotic necrosis, and a reduction in liver volume. These findings were consistent across replicate experiments. Time-lapse imaging indicated the onset of injury was 6 h after the start of exposure, at which point, RNA-sequencing revealed that 88% of genes were down-regulated. Immune response associated genes were up-regulated in the triptolide-treated larvae including nitric oxide synthase. Inhibition of nitric oxide synthase increased mortality. Triptolide induces hepatotoxicity in zebrafish larvae. This represents a new model of drug-induced liver injury that complements rodents. RNA sequencing, guided by time-lapse microscopy, revealed early down-regulation of genes consistent with previous invitro studies, and facilitated the discovery of mechanistic inflammatory pathways.