Identification of natriuretic peptide receptor A (NPR-A) expression signatures in podocytes in vivo reveals baseline control of protective pathways including Protein S
Natriuretic peptide receptor-A (NPR-A) is the principal receptor for the natriuretic peptides ANP and BNP. Targeted deletion of NPR-A in mouse glomerular podocytes significantly enhances renal injury in vivo in the DOCA-salt experimental model. It was therefore hypothesized that natriuretic peptides exert a direct protective effect on glomerular barrier integrity through activation of NPR-A and modulation of gene expression patterns in podocytes. RNA-seq analysis revealed a total of 158 DEGs with 81 downregulated DEGs and 77 upregulated DEGs in Npr1 deficient podocytes. Among the downregulated genes were protein S and semaphorin 3G, which are known to have a protective effect in podocytes. Protein S was also expressed in and secreted from isolated human glomeruli. GO enrichment analysis revealed that the upregulated DEGs in NPR-A deficient podocytes were associated with cell migration and motility. In line, BNP significantly decreased podocyte outgrowth from cultured glomeruli. Overall design: Green fluorescence-positive podocytes from mice with a conditional deletion of Npr1 encoding NPR-A were isolated by fluorescence-activated cell sorting (FACS). Differentially expressed genes (DEGs) in podocytes were identified by RNA sequencing of podocytes from wild-type and NPR-A deleted mice