Abstract: SA-PO161
A Novel RIPK3/BRD4 Small Molecule Inhibits Arsenical-Induced AKI
Session Information
- AKI: Mechanisms - III
November 04, 2023 | Location: Exhibit Hall, Pennsylvania Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Acute Kidney Injury
- 103 AKI: Mechanisms
Authors
- Melkonian, Arin, The University of Alabama at Birmingham, Birmingham, Alabama, United States
- Moore, Kyle H., The University of Alabama at Birmingham, Birmingham, Alabama, United States
- Traylor, Amie, The University of Alabama at Birmingham, Birmingham, Alabama, United States
- Black, Laurence Marie, The University of Alabama at Birmingham, Birmingham, Alabama, United States
- Zmijewska, Anna Alicja, The University of Alabama at Birmingham, Birmingham, Alabama, United States
- Esman, Stephanie, The University of Alabama at Birmingham, Birmingham, Alabama, United States
- Srivastava, Ritesh, The University of Alabama at Birmingham, Birmingham, Alabama, United States
- Athar, Mohammad, The University of Alabama at Birmingham, Birmingham, Alabama, United States
- George, James F., The University of Alabama at Birmingham, Birmingham, Alabama, United States
- Agarwal, Anupam, The University of Alabama at Birmingham, Birmingham, Alabama, United States
Background
Arsenicals such as lewisite, cause blistering of the skin as well as lung, kidney, and multi-organ damage. The development of antidotes to warfare chemicals is a priority of the NIH CounterACT Program. To this end, we used single nucleus RNA sequencing (snRNAseq) to explore the nephrotoxic effects of phenylarsine oxide (PAO, a lewisite mimic) in an unbiased manner and synthesized a novel dual inhibitor (duali) that targets two necroptotic markers that are upregulated after lewisite exposure: receptor interacting serine/threonine kinase 3 (RIPK3) and bromodomain-containing protein 4 (BRD4). BRD4 plays a critical role in inflammation and redox metabolism. Here we identify transcriptional alterations in the kidney following arsenical-induced damage and test the hypothesis that the duali protects against injury using in vivo and in vitro models.
Methods
snRNAseq was performed on kidneys from mice treated topically with PAO (4mg/kg) or vehicle for 6 and 24 hours. Protective effects of duali were evaluated in vitro utilizing proximal tubule cells (PTCs). Cells were pretreated with duali 1 h before PAO and examined via immunostaining, western blots, and qPCR at 4, 20, or 24 hours. In vivo efficacy was assessed 24 h post PAO (4-6mg/kg). Duali was applied topically 30 min post PAO exposure.
Results
Duali treatment inhibits phospho- mixed lineage kinase domain-like pseudokinase (MLKL) and total RIPK3 and MLKL transcripts (p <0.05) in vitro. We also observed a recovery of glomerular filtration rate in PAO exposed mice following duali treatment, which was associated with decreased expression of pRIPK3. snRNAseq in PAO treated mice revealed that fatty acid (FA) β-oxidation, FA biosynthesis, and PPAR-alpha pathways were upregulated in PTC and endothelial cells.
Conclusion
While the treatment with duali ameliorated PAO induced kidney injury, the mechanism of action remains to be elucidated. We have shown that cutaneous PAO exposure alters gene transcription and upregulates FA metabolism suggesting a compensatory response following metabolic perturbation. We conclude that our duali may be used as a potential therapeutic in arsenical-induced AKI. Future studies aim to confirm the precise mechanisms behind BRD4- and duali-mediated improvements of renal function.
Funding
- Other NIH Support