Abstract P2022: The Jak3 Pathway is Involved in the Benefit of the Mineralocorticoid Receptor Antagonist Finerenone in Acute and Chronic Kidney Injury Following Ischemia-Reperfusion

Introduction: Mineralocorticoid receptor antagonists (MRA) prevent ischemic acute kidney injury (AKI) and its transition to chronic kidney disease (CKD). The specific contribution of interleukin-4 (IL-4) signaling pathway to this effect is unknown.

Objective: To gain insight into the role of IL-4 signaling and specifically the Jak3 pathway in the MRA protective effect of Finerenone.

Methods: Male C57/B6 mice (48) were divided in: sham, renal ischemia for 22.5 min (IR), IR plus treatment with the non-steroidal MRA finerenone (10 mg/kg) and IR-finerenone plus Tofacitinib (15mg/kg), a JAK3 inhibitor at -48, -24 and -1 h before IR. The mice were followed-up for 24 hours or 4 weeks to evaluate the AKI to CKD transition.

Results: At 24h post-injury, finerenone showed benefits on various parameters while concomitant Jak3 inhibition blunted these effects: plasma creatinine (uM/l, 40.8±6.1 IR, 13.2±1.3 Fine, 31.9±5.4 Jak3i, mean+/-SEM) and urea (mM/l; 39.5±6.1 IR, 10.7±0.5 Fine, 25.4±4.1 Fine+Jak3i, mean+/-SEM) and protects from acute tubular necrosis (rel. values: 1.34±0.19 IR, 0.47±0.14 Fine, 1.18±0.17 Fine+Jak3i, mean+/-SEM) We previously showed that finerenone has an important role in changing the macrophage phenotype from M1 (pro-inflammatory) to M2 (anti-inflammatory) profile. Finerenone treatment decreased expression of M1 markers, an effect blunted by Jak3 inhibition. One month after injury, the AKI to CKD transition was evidenced by a 40% increase in plasma creatinine, in interstitial fibrosis and increased mRNA levels of various profibrotic markers. Finerenone treatment protected against these alterations while the JAK3 inhibitor reversed the Finerenone protective effects on interstitial fibrosis (rel. values: 1.95±0.15 IR, 0.33±0.08 Fine, 0.91±0.14 Fine+Jak3i, mean+/-SEM) and on profibrotic markers (rel. values, mean±SEM): fibronectin (17.18±3.93 IR, 3.40±0.77 Fine, 12.62±4.32 Fine+Jak3i), col1a (8.76±2.07 IR, 4.33±0.08 Fine, 19.24±1.55 Fine+Jak3i), α-sma (5.42±1.27 IR, 1.77±0.15 Fine, 6.88±1.61 Fine+Jak3i)

Conclusion: MR antagonism with finerenone counteracts the acute and chronic deleterious effects after renal ischemic injury. The IL-4 receptor-JAK3 signaling pathway is involved in the benefit of the MRA finerenone.