Calycosin plays a protective role in diabetic kidney disease through the regulation of ferroptosis

Context: Diabetic kidney disease (DKD) is a devastating complication of diabetes. Renal functional deterioration caused by tubular injury is the primary change associated with this disease. Calycosin shows protective roles in various diseases.

Objectives: This study explored the function and underlying mechanism of calycosin in DKD.

Materials and methods: HK-2 cells were treated with 25 mM high glucose (HG) to establish a renal tubule injury cell model. Then, the viability of cells treated with 0, 5, 10, 20, 40 and 80 μM of calycosin was measured using Cell Counting Kit-8. For the in vivo model, db/db mice were treated with 10 and 20 mg/kg/day of calycosin; db/m mice served as controls. The histomorphology was analyzed via haematoxylin and eosin staining.

Results: HG-induced decreased expression of glutathione (491.57 ± 33.56 to 122.6 ± 9.78 μmol/mL) and Glutathione Peroxidase 4 (inhibition rate 92.3%) and increased expression of Lactate Dehydrogenase (3.85 ± 0.89 to 16.84 ± 2.18 U/mL), malondialdehyde (3.72 ± 0.66 to 18.2 ± 1.58 nmol/mL), lipid ROS (4.31-fold increase) and NCOA4 (7.69-fold increase). The effects induced by HG could be blocked by calycosin. Moreover, calycosin alleviated the HG-induced decrease of cell viability and the increase of lipid ROS, but erastin could block the effects caused by calycosin. The in vivo model showed that calycosin alleviated the renal injury caused by diabetes.

Discussion and conclusion: Calycosin has a protective effect on diabetic kidney disease; Ferroptosis may be involved in this process.