Pretreatment of mice with a low hepatotoxic dose of acetaminophen (APAP) results in resistance to a subsequent, higher dose of APAP. This mouse model, termed APAP autoprotection was used here to identify differentially expressed genes and cellular pathways that could contribute to this development of resistance to hepatotoxicity. Male C57BL/6J mice were pretreated with APAP (400mg/kg) and then challenged 48h later with 600mg APAP/kg. Livers were obtained 4 or 24h later and total hepatic RNA was isolated and hybridized to Affymetrix Mouse Genome MU430_2 GeneChip. Statistically significant genes were determined and gene expression changes were also interrogated using the Causal Reasoning Engine (CRE). Extensive literature review narrowed our focus to methionine adenosyl transferase-1 alpha (MAT1A), nuclear factor (erythroid-derived 2)-like 2 (Nrf2), flavin-containing monooxygenase 3 (Fmo3) and galectin-3 (Lgals3). Down-regulation of MAT1A could lead to decreases in S-adenosylmethionine (SAMe), which is known to protect against APAP toxicity. Nrf2 activation is expected to play a role in protective adaptation. Up-regulation of Lgals3, one of the genes supporting the Nrf2 hypothesis, can lead to suppression of apoptosis and reduced mitochondrial dysfunction. Fmo3 induction suggests the involvement of an enzyme not known to metabolize APAP in the development of tolerance to APAP toxicity. Subsequent quantitative RT-PCR and immunochemical analysis confirmed the differential expression of some of these genes in the APAP autoprotection model. In conclusion, our genomics strategy identified cellular pathways that might further explain the molecular basis for APAP autoprotection.

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3901410PMC
http://dx.doi.org/10.1016/j.taap.2013.09.025DOI Listing

Publication Analysis

Top Keywords

apap autoprotection
12
apap
9
gene expression
8
cellular pathways
8
apap toxicity
8
analysis changes
4
changes hepatic
4
hepatic gene
4
expression murine
4
murine model
4

Similar Publications

Article Synopsis
  • A better understanding of autoprotection against drug-induced liver injury (DILI) could lead to new prevention and treatment strategies, but the underlying mechanisms are not well understood.
  • Researchers used single-cell RNA sequencing to study non-parenchymal liver cells in mice pretreated with a low dose of acetaminophen (APAP) to see how they responded to a higher dose later on.
  • Specific subsets of non-parenchymal cells, like endothelial and dendritic cells, were linked to liver protection and repair mechanisms, revealing potential pathways for enhancing liver resistance to acetaminophen toxicity.
View Article and Find Full Text PDF

From hepatoprotection models to new therapeutic modalities for treating liver diseases: a personal perspective.

F1000Res

August 2016

Toxicology Program, Department of Pharmaceutical Sciences, School of Pharmacy, University of Connecticut, Storrs, CT, USA.

A variety of rodent models of hepatoprotection have been developed in which tolerance to acetaminophen-induced hepatotoxicity occurs. Autoprotection/heteroprotection is a phenomenon where prior exposure to a mildly toxic dose of toxicant confers protection against a subsequently administered higher dose of the same toxicant (as in the case of autoprotection) or to a different toxicant (referred to as heteroprotection). Multiple mechanisms regulate this adaptive response, including hepatocellular proliferation, proteostasis, enhanced expression of cytoprotective genes, and altered tissue immune response.

View Article and Find Full Text PDF
Article Synopsis
  • * The study uses quantitative mass spectrometry to analyze the liver's response to acetaminophen in rats, finding that 30% of all detected liver proteins are involved in this response.
  • * A master regulator of cellular defense, NFE2L2, has minimal impact on this adaptation, indicating that multiple pathways may contribute, while changes in protein localization may help avoid reaching toxic levels.
View Article and Find Full Text PDF

Acetaminophen (APAP) pretreatment with a hepatotoxic dose (400 mg/kg) in mice results in resistance to a second, higher dose (600 mg/kg) of APAP (APAP autoprotection). Recent microarray work by our group showed a drastic induction of liver flavin containing monooxygenase-3 (Fmo3) mRNA expression in our mouse model of APAP autoprotection. The role of liver Fmo3, which detoxifies xenobiotics, in APAP autoprotection is unknown.

View Article and Find Full Text PDF

Pretreatment of mice with a low hepatotoxic dose of acetaminophen (APAP) results in resistance to a subsequent, higher dose of APAP. This mouse model, termed APAP autoprotection was used here to identify differentially expressed genes and cellular pathways that could contribute to this development of resistance to hepatotoxicity. Male C57BL/6J mice were pretreated with APAP (400mg/kg) and then challenged 48h later with 600mg APAP/kg.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!