Multiple microRNAs function as self-protective modules in acetaminophen-induced hepatotoxicity in humans

Area of Science:

• Hepatology
• Molecular Biology
• Pharmacology

Background:

• Acetaminophen (APAP) overdose is a primary cause of acute liver failure.
• The molecular mechanisms of adaptive tolerance to APAP-induced liver injury remain incompletely understood.
• Understanding these mechanisms is crucial for developing precision medicine approaches for APAP-related liver conditions.

Purpose of the Study:

• To systematically analyze mRNA and microRNA (miRNA) expression profiles in APAP-treated HepaRG cells.
• To identify specific miRNAs that target key genes involved in APAP hepatotoxicity.
• To investigate the role of these miRNAs in cellular adaptive responses to APAP overdose.

Main Methods:

• Next-generation sequencing was used to profile gene and miRNA expression in APAP-treated HepaRG cells.
• In silico prediction, gene ontology, and network analyses identified putative miRNAs targeting dysregulated genes.
• Luciferase reporter assays, RNA electrophoresis mobility shift assays, and miRNA pull-down assays validated miRNA-target interactions.
• Serum samples from children with APAP overdose and healthy controls were analyzed for specific miRNA levels.

Main Results:

• 2758 differentially expressed genes and 47 miRNAs were identified in APAP-treated cells.
• Four miRNAs (hsa-miR-224-5p, hsa-miR-320a, hsa-miR-449a, hsa-miR-877-5p) were found to suppress drug-metabolizing enzyme (DME) expression by downregulating HNF1A, HNF4A, and NR1I2.
• Transfection of these miRNAs protected HepaRG cells from APAP toxicity, evidenced by reduced alanine aminotransferase levels.
• Serum levels of hsa-miR-320a and hsa-miR-877-5p were significantly elevated in children with APAP overdose.

Conclusions:

• Hsa-miR-224-5p, hsa-miR-320a, hsa-miR-449a, and hsa-miR-877-5p suppress DME expression implicated in APAP-induced hepatotoxicity.
• These miRNAs contribute to an adaptive response in hepatocytes against APAP-induced liver injury.
• The findings provide insights into molecular mechanisms of APAP tolerance and potential therapeutic targets.