2, 3, 7, 8-Tetrachlorodibenzo-p-Dioxin (TCDD)-Inducible Poly-ADP-Ribose Polymerase (TIPARP/PARP7) Catalytic Mutant Mice (TiparpH532A) Exhibit Increased Sensitivity to TCDD-Induced Hepatotoxicity and Lethality. (15th June 2021)

• Record Type: Journal Article
• Authors: Hutin, David; Long, Alexandra S; Sugamori, Kim; Shao, Peng; Singh, Sachin Kumar; Rasmussen, Marit; Olafsen, Ninni Elise; Pettersen, Solveig; Grimaldi, Giulia; Grant, Denis M; Matthews, Jason
• Is Part Of: Toxicological sciences. Volume 183:Number 1(2021)
• Page Start: 154
• Page End: 169
• Publication Date: 2021-06-15
• Subjects: aryl hydrocarbon receptor -- wasting syndrome -- ADP-ribosylation -- 2, 3, 7, 8-tetrachlorodibenzo-p-dioxin -- TCDD-inducible poly-ADP-ribose polymerase (TIPARP) -- poly-ADP-ribose polymerase 7 (PARP7) -- ADP-ribosyltransferase diphtheria toxin-like 14 (ARTD14); Toxicology -- Periodicals; Toxicology -- Periodicals; Toxicology; Periodicals; 615.9
• DOI: 10.1093/toxsci/kfab075
• Languages: English
• ISSNs: 1096-6080

Abstract

Abstract: 2, 3, 7, 8-tetrachlorodibenzo- p -dioxin (TCDD)-inducible poly-adenosine diphosphate (ADP)-ribose polymerase (TIPARP/PARP7), an aryl hydrocarbon receptor (AHR) target gene and mono-ADP-ribosyltransferase, acts as part of a negative feedback loop to repress AHR signaling. This process is prevented by a single H532A mutation in TIPARP that destroys its catalytic activity. We hypothesized that the loss of TIPARP catalytic activity would increase sensitivity to TCDD-induced toxicity in vivo . To test this, we created a catalytically deficient mouse line ( Tiparp H532A ) by introducing a single H532A mutation in TIPARP. Treatment of mouse embryonic fibroblasts or hepatocytes isolated from Tiparp H532A mice confirmed the increased TCDD-induced expression of the AHR target genes Cyp1a1, Cyp1b1, and Tiparp . Tiparp H532A mice given a single injection of 10 µg/kg TCDD, a nonlethal dose in Tiparp +/+ mice, did not survive beyond day 10. All Tiparp +/+ mice survived the 30-day treatment. TCDD-treated Tiparp H532A mice displayed increased expression of AHR target genes, increased steatohepatitis and hepatotoxicity. Hepatic RNA-sequencing revealed 7-fold more differentially expressed genes in Tiparp H532A mice than in Tiparp +/+ mice (4542 vs 647 genes) 6 days after TCDD treatment. Differentially expressed genes included genes involved in xenobiotic metabolism, lipid homeostasis and inflammation. Taken together, these data further support TIPARP as a critical negative regulator of AHR activity and show that loss of its catalytic activity is sufficient to increase sensitivity to TCDD-induced steatohepatitis and lethality. Since TIPARP inhibition has recently emerged as a potential anticancer therapy, the impact on AHR signaling, TCDD and polycyclic aromatic hydrocarbon toxicity will need to be carefully considered under conditions of therapeutic TIPARP inhibition.