Kidney Week

Abstract: FR-PO237

Effects of KCNN4 Blockade With Senicapoc in Kidney Cell-Based Assays and a Mouse Model of Renal Inflammation and Fibrosis

Session Information

• Pharmacology
  November 04, 2022 | Location: Exhibit Hall, Orange County Convention Center‚ West Building
  Abstract Time: 10:00 AM - 12:00 PM

Category: Pharmacology (PharmacoKinetics‚ -Dynamics‚ -Genomics)

• 1900 Pharmacology (PharmacoKinetics‚ -Dynamics‚ -Genomics)

Authors

• Zhou, Peng, Janssen Research and Development LLC, Boston, Massachusetts, United States

Peng Zhou,

• Hinke, Simon A., Janssen Research and Development LLC, Spring House, Pennsylvania, United States

Simon A. Hinke,

• Cavanaugh, Cassandre, Janssen Research and Development LLC, Boston, Massachusetts, United States

Cassandre Cavanaugh,

• Ma, Li-Jun, Janssen Research and Development LLC, Spring House, Pennsylvania, United States

Li-Jun Ma,

• Myshkin, Eugene, Janssen Research and Development LLC, Boston, Massachusetts, United States

Eugene Myshkin,

• Shukla, Neetu, Janssen Research and Development LLC, Spring House, Pennsylvania, United States

Neetu Shukla,

• Natoli, Thomas A., Janssen Research and Development LLC, Boston, Massachusetts, United States

Thomas A. Natoli,

• Silva, Jose M., Janssen Research and Development LLC, Spring House, Pennsylvania, United States

Jose M. Silva,

• Magnone, Maria chiara, Janssen Research and Development LLC, Boston, Massachusetts, United States

Maria chiara Magnone,

• Yang, Zhiyong, Janssen Research and Development LLC, Boston, Massachusetts, United States

Zhiyong Yang,

Background

Progressive kidney fibrosis including tubulointerstitial fibroblast proliferation and mesangial matrix expansion is a common manifestation in chronic kidney disease, resulting in end-stage kidney disease. KCNN4 (KCa3.1) is an intermediate-conductance Ca²⁺-activated K⁺ channel implicated in immune cell activation, cytokine production, and fibroblast proliferation. Previous studies have shown the pathophysiological relevance of KCNN4 in fibrotic disease.

Methods

Here, we explored the pathological role of KCNN4 in renal fibrosis. Specifically, we assessed the impact of a potent and selective KCNN4 inhibitor Senicapoc in kidney cell-based assays, and in a mouse model of renal fibrosis induced by Unilateral Ureteral Obstruction (UUO).

Results

In situ hybridization and immunohistochemistry showed KCNN4 is expressed mainly in tubular and interstitial cells in human kidney samples. In vitro, whole cell patch clamp confirmed the inhibition of K⁺ current by Senicapoc (IC₅₀ ~2nM). In human renal fibroblasts, Senicapoc dose-dependently inhibited TGF-β-stimulated proliferation, but did not inhibit mRNA expression of TGF-β-stimulated fibrotic genes in human renal fibroblast or proximal tubular epithelial cells. In vivo, Kcnn4 expression was upregulated ~20-fold in UUO-induced fibrotic kidney and decreased with anti-TGFβ-1 antibody treatment in UUO model. Senicapoc treatment (100mpk BID, 200mpk QD or BID) at doses much higher than those commonly used in reported literature did not improve kidney histology or decrease mRNA expression of inflammatory and fibrotic genes in a 10-day mouse UUO model. PK studies showed dramatic decrease in plasma compound exposure levels after repeat dosing when measured at day 3 and thereafter in both mice and rats, potentially indicating insufficient target coverage in the UUO study.

Conclusion

In summary, while KCNN4 may play a role in kidney disease, the PK profile of Senicapoc makes it not suitable for target validation studies in rodents. A compound with better exposure profile is needed in order to properly study the effects of KCNN4 blockage in a rodent disease model.