Abstract: In recent years, it has been found that the lack of vitamin D receptor (VDR) activation is closely associated with the development of cardiorenal syndrome (CRS). Hydroxylation catalyzed by renal 25-hydroxyvitamin D-1α hydroxylase(CYP27B1) is responsible for over 90% circulating concentrations of vitamin D activation, which then exerts biologic actions of vitamin D. Loss of renal CYP27B1 during CRS is associated with gradual decline in circulating 1,25(OH)2D3, resulting in inadequate VDR activation in renal and cardiac tissues, thereby promoting renal and cardiac damages. Therefore, CYP27B1 and VDR may become key targets for the combination of chronic kidney disease and cardiovascular disease. In this paper,the roles of vitamin D / VDR and metabolic regulation of CYP27B1 in CRS are reviewed, which may also provide new therapeutic strategies for CRS.

Key words: vitamin D, calcitriol, receptors, calcitriol, CYP27B1, cardiorenal syndrome