GSE159200
Identification of translational microRNA biomarker candidates for ketoconazole-induced liver injury using next-generation sequencing
Drug induced liver injury (DILI) is a leading cause of acute liver failure. Reliable and translational biomarkers are needed for early detection of DILI. microRNAs (miRNAs) have received wide attention as a novel class of potential DILI biomarkers. However, it is unclear how DILI drugs other than acetaminophen may influence miRNA expression or which miRNAs could serve as useful biomarkers in humans. We selected ketoconazole (KCZ), a classic hepatotoxin, to study miRNA biomarkers for DILI as a proof-of-concept for a workflow that integrated in vivo, in vitro, and bioinformatics analyses. We examined hepatic miRNA expression in KCZ-treated rats at multiple doses and durations using miRNA-sequencing and correlated our results with conventional DILI biomarkers such as liver histology. Significant dysregulation of rno-miR-34a-5p, rno-miR-331-3p, rno-miR-15b-3p, and rno-miR-676 was associated with cytoplasmic vacuolization, a phenotype in rat livers with KCZ-induced injury, which preceded the elevation of serum liver transaminases (ALT and AST). Between rats and humans, miR-34a-5p, miR-331-3p, and miR-15b-3p were evolutionarily conserved with identical sequences, whereas miR-676 showed 73% sequence similarity. Using quantitative PCR, we found that the levels of hsa-miR-34a-5p, hsa-miR-331-3p, and hsa-miR-15b-3p were significantly elevated in the culture media of HepaRG cells treated with 100 mM KCZ (a concentration that could induce cytotoxicity). Additionally, we computationally characterized the miRNA candidates for their gene targeting, target functions, and miRNA/target evolutionary conservation. In conclusion, we identified miR-34a-5p, miR-331-3p, and miR-15b-3p as translational biomarker candidates for early detection of KCZ-induced liver injury with a workflow applicable to computational toxicology studies. Overall design: Male Sprague-Dawley rats (6-week old) were orally administered with ketoconazole (KCZ) at the low (10 mg/kg), middle (30 mg/kg), or high dose (100 mg/kg) per day for 3, 7, and 14 days, respectively. Rats treated with 0.5% methylcellulose (a vehicle for KCZ) for each of the three durations served as a corresponding control for that timepoint. Each treatment condition indicated a unique combination of a dose (control, low, middle, or high) and a timepoint (3, 7, or 14 days), totaling 12 conditions in this study. Rats were sacrificed and livers were collected 24 h after the final dosing.