Natriuretic Peptide Augmentation Attenuates Renin Cell Hyperactivation and Afferent Arteriolar Hypertrophy During Long-Term Renin-Angiotensin System Inhibition

BACKGROUNDChronic renin-angiotensin system (RAS) inhibition activates renin cells and induces afferent arteriolar hypertrophy, a maladaptive vascular response that may contribute to nephrosclerosis-like renal injury. Although genetic or cell ablation approaches have shown that renin cells are required for this remodeling, no pharmacological strategy to restrain hyperactivated renin cells while preserving RAS inhibition benefits has been established. Natriuretic peptides (NPs) counteract RAS; however, whether NP signaling modulates renin cell activation and afferent arteriolar remodeling remains unclear. METHODSWe examined direct effects of atrial natriuretic peptide (ANP) on As4.1 renin-producing cells using reverse transcription-quantitative PCR, ELISA, and RNA sequencing (RNA-seq). We established a mouse model of long-term RAS inhibition using valsartan, an angiotensin II receptor blocker (ARB), and compared it with sacubitril/valsartan, an angiotensin receptor-neprilysin inhibitor (ARNI). Valsartan was matched between the ARB and ARNI groups. Renin cell activation, afferent arteriolar remodeling, and renal injury were evaluated using biochemical assays, histology, immunostaining, single-nucleus RNA-seq, and region-specific photo-isolation chemistry RNA-seq of afferent arteriolar/juxtaglomerular regions. RESULTSANP suppressed Ren1 expression and renin secretion in As4.1 cells; this effect was attenuated by a natriuretic peptide receptor A antagonist. RNA-seq demonstrated that ANP induced receptor-dependent remodeling of renin cell gene programs. In mice, long-term ARB treatment induced renin cell hyperactivation, expansion of renin-positive juxtaglomerular regions, afferent arteriolar hypertrophy, renal dysfunction, tubular injury markers, and fibrosis. ARNI increased plasma ANP levels and attenuated these pathological changes, despite a comparable blood pressure reduction. Single-nucleus transcriptomics revealed attenuation of tubular injury-associated cellular states and altered renin cell-associated mesenchymal programs with ARNI. Region-specific transcriptomics further demonstrated distinct molecular states in afferent arteriolar/juxtaglomerular regions between ARB- and ARNI-treated kidneys. Integrated transcriptomic analysis suggested that NP signaling converges on vascular regulatory programs in hyperactivated renin-expressing cells. CONCLUSIONSNP signaling acts as a pharmacologically augmentable modulator of maladaptive renin cell activation. ARNI attenuates renin cell hyperactivation, afferent arteriolar hypertrophy, and renal injury during long-term RAS inhibition, suggesting that neprilysin inhibition may preserve RAS blockade benefits while limiting renin cell-driven renal vascular remodeling.