RUNX2 and chronic kidney disease: Besides, compared with the control group, the expression of Runx2 in the blood vessels of the mice in the CKD group was higher and the expression of α-SMA was lower; compared with the CKD group, the expression of Runx2 was lower, and the expression of α-SMA was higher in the CKD+Spir group, indicating that Spir can reduce the osteogenic transdifferentiation of vascular cells in CKD mice and improve vascular calcification.