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Accumulating evidence shows that renal fibrosis plays a key role in the development of hypertensive nephropathy (HTN). Therefore, a better understanding of the underlying mechanism of renal fibrosis regulation in HTN would be critical for designing rational strategies for therapeutic interventions. In this study, we revealed that GPR97, a novel identified adhesion G coupled receptor, plays an important role in the regulation of Wnt/β‐catenin signaling, which is the crucial driver of renal fibrosis in HTN. First, we identified that the expression of GPR97 correlated with the β‐catenin expression in renal biopsy from patients with HTN. Moreover, we found that GPR97 deficiency inhibited Wnt/β‐catenin signaling in mice with HTN, as evidenced by the reduction of β‐catenin expression and downstream target proteins, including MMP7 and Fibronectin. Mechanistically, we found that GPR97 could directly bind with Wnt1 in cultured tubular cells and TGF‐β1 treatment enhanced the binding ability of GPR97 and Wnt1. In addition, the gene silencing of GPR97 could decrease the Wnt1‐induced fibrotic phenotype of tubular cells and inflammatory responses, suggesting that the binding of GPR97 and Wnt1 promoted Wnt/β‐catenin signaling. Collectively, our studies reveal that GPR97 is a regulator of Wnt/β‐catenin signaling in HTN, and targeting GPR97 may be a novel therapeutic strategy for HTN treatment. [ABSTRACT FROM AUTHOR]

Abstract: Adhesion G-protein-coupled receptors (GPCR) are special members of GPCRs with long N-termini containing multiple domains. We overexpressed our collection of receptors together with G-proteins in mammalian cell lines and measured the concentrations of intracellular signaling molecules, such as inositol phosphate and cAMP. Our results show that a subset of tested adhesion GPCRs has constitutive activities and is capable of coupling to a variety of G-proteins. In addition, we have identified a small molecule compound that specifically activates one of the subfamily members, GPR97, and the activation was confirmed by an independent GTPγS assay. These findings suggest classical GPCR screening assays could be applied to de-orphanize these receptors, and provide pharmacological tools to improve understanding of the physiological functions of these receptors. [Copyright &y& Elsevier]