Kidney Week

Abstract: FR-PO408

Deficiency of Peroxiredoxin-4 and Dopamine D5 Receptor Increases NLRP3-Inflammasome Activity

Session Information

• Hypertension and CVD: Basic
  November 03, 2023 | Location: Exhibit Hall, Pennsylvania Convention Center
  Abstract Time: 10:00 AM - 12:00 PM

Category: Hypertension and CVD

• 1601 Hypertension and CVD: Basic

Authors

• Polzin, Jacob Quentin Mullins, The George Washington University School of Medicine and Health Sciences, Washington, District of Columbia, United States

Jacob Quentin Mullins Polzin,

• Amatya, Bibhas, The George Washington University School of Medicine and Health Sciences, Washington, District of Columbia, United States

Bibhas Amatya,

• Asico, Laureano D., The George Washington University School of Medicine and Health Sciences, Washington, District of Columbia, United States

Laureano D. Asico,

• Armando, Ines, The George Washington University School of Medicine and Health Sciences, Washington, District of Columbia, United States

Ines Armando,

• Felder, Robin Allen, University of Virginia School of Medicine, Charlottesville, Virginia, United States

Robin Allen Felder,

• Jose, Pedro A., The George Washington University School of Medicine and Health Sciences, Washington, District of Columbia, United States

Pedro A. Jose,

• Lee, Hewang, The George Washington University School of Medicine and Health Sciences, Washington, District of Columbia, United States

Hewang Lee,

Background

Dopamine 5 receptor (D₅R) interacts with Peroxiredoxin-4 (PRDX4) to reduce oxidative stress and inflammation. Drd5 knockout (Drd5^-/-) mice are hypertensive and in a state of oxidative stress and chronic inflammation. However, the gene’s specific association with the regulation of inflammasomal activity in the kidney is unknown.

Methods

To investigate inflammasomal activity, the protein expressions of interleukin (IL)-1β, IL-18, and caspase-1 were quantified by immunoblotting. The PRDX4 gene was silenced in HEK 293 cells overexpressing D₅R. Drd5^-/- mice were generated as previously reported.

Results

D₅R protein expression was decreased in PRDX4 siRNA-transfected D₅R-HEK 293 cells (PRDX4 siRNA: 58.8±6.7% vs Mock: 100.0±9.6%, n=4), and PRDX4 protein was also reduced in the kidney cortices of Drd5^-/- mice (Drd5^+/+: 100±12.8%, n=3; D₅R^-/-: 69.2±7.5%, n=4). In D₅R-HEK 293 cells -transfected with PRDX4 siRNA, the protein expressions of nucleotide-binding oligomerization domain, leucine-rich repeat, and pyrin domain-containing-3 (NLRP3) were increased compared with mock-transfected cells (siRNA: 142.7±8.9%, Mock: 100±1.8%). The protein expressions of cleaved IL-1β (siRNA: 176.3±37.0%, Mock: 100.0±12.7%) and cleaved IL-18 (siRNA:710.0±214.8%, Mock: 100±8.1%) were likewise increased compared with mock- transfected cells, indicating an increase in inflammatory response due to NLRP3 activity. The increase in NLRP3 activity with silenced PRDX4 was attenuated by tempol, a superoxide dismutase mimetic, in D₅R-HEK293 cells, indicating that oxidative stress was upstream of the increase in NLRP3-associated inflammasomal activity induced by PRDX4 deficiency. Consequently, protein expression of cleaved caspase-1 was increased in renal cortices from Drd5^-/- mice (Drd5^+/+: 100±2.6%; Drd5^-/-:112.6±3.1%, n=3). Consistent with this increase, the protein expressions of cleaved IL-1β (Drd5^+/+: 100.0±11.1%, n=3; Ddr5^-/-:152.9±13.5%, n=4), secreted IL-1β (Drd5^+/+: 100.0±1.5%, n=3; Drd5^-/-:137.4±2.2%, n=4), and cleaved IL-18 (Drd5^+/+: 100.0±8.3%; Drd5^-/-:166.0±10.4%, n=3) were also increased compared with their wild-type littermates.

Conclusion

The increase in renal inflammation associated with PRDX4 deficiency in Drd5^-/- mice is due to the increase in NLRP3-inflammasome activity.

Funding

• NIDDK Support