Relation between serum cathepsin D levels and endothelial dysfunction in patients with chronic kidney disease

We aimed to investigate the role of cathepsin D, an inflammatory and atherosclerotic mediator, in endothelial dysfunction in chronic kidney disease. The study included 65 patients with stage 2–4 chronic kidney disease (35 females, 30 males; mean age, 55.8±15.6 years). Serum creatinine and cathepsin D levels and glomerular filtration rates (GFRs) were determined, and brachial flow-mediated dilation (FMD) percentage was measured by two-dimensional gray scale and color flow Doppler and vascular imaging. FMD ≤6% was considered to indicate endothelial dysfunction. Mean GFR, median creatinine levels, and median cathepsin D levels were 40.2±11.2mL/min/1.73m2, 1.7mg/dL, and 819.75ng/mL, respectively. Endothelial dysfunction was present in 30 of the 65 patients (46.2%). There was a significant difference between groups with and without endothelial dysfunction in terms of cathepsin D (p=0.001) and creatinine (p=0.03) levels, and negative and significant correlations were found between brachial artery FMD% and cathepsin D (r=−0.359, p=0.003) and creatinine (r=−0.304, p=0.014) levels. Cathepsin D, which is known to be associated with atherosclerosis, may play a role in the process of endothelial dysfunction. Further studies are essential to determine the exact function of cathepsin D in endothelial dysfunction in chronic kidney disease and to determine its value as a tool for early diagnosis and target for treatment of cardiovascular diseases in patients with chronic kidney disease.