Nonepithelial mineralocorticoid receptor activation as a determinant of kidney disease

Chronic kidney disease is a major global health challenge, and mineralocorticoid receptor (MR) signaling is thought to play a role in disease progression. The classic role of the MR is the regulation of fluid and electrolyte homeostasis via differential gene expression, and recently its role in modulating inflammation and fibrosis has been identified. In addition to expression of the MR in renal epithelial cells, it is also found in nonepithelial cells, such as endothelial cells, vascular smooth muscle cells, podocytes, and fibroblasts. Targeting the MR in these cells may play a role in offering protection against inflammation and fibrosis in the kidneys and the cardiovascular system. Herein, data from preclinical cell-specific MR knockout mouse models and in vitro studies that help uncover the role of the MR in nonepithelial cells are presented. This review also discusses several potential targets that offer opportunities for the targeting of MR signaling in nonepithelial cells.