TIMP1 and chronic kidney disease: During CKD progression, uremic toxins can enhance the expression of tissue inhibitors of metalloproteinase 1 (TIMP-1), transforming growth factor beta 1 (TGF-β1) [4], osteopontin [5], and endothelin 1 to induce epithelial-to-mesenchymal transition (EMT) [6,7], leading to cardiovascular system damage and skeletal abnormalities (Figure 1).