Relationship Between Serum Myostatin and Endothelial Function in Non-Dialysis Patients with Chronic Kidney Disease.

BACKGROUND/OBJECTIVES: Myostatin, primarily produced by skeletal muscle, inhibits muscle growth and promotes protein degradation. It has been implicated in conditions such as obesity, insulin resistance, and cardiovascular disease. However, its association with endothelial function in chronic kidney disease (CKD) patients remains unclear. This study aimed to investigate the relationship between serum myostatin levels and endothelial function in 136 non-dialysis CKD patients at stages 3-5. METHODS: Fasting blood samples were collected to measure serum myostatin levels using enzyme-linked immunosorbent assay kits. Endothelial function was evaluated non-invasively by measuring the vascular reactivity index (VRI) with a digital thermal monitoring test. RESULTS: VRI values were classified as poor (<1.0, n = 25, 18.4%), intermediate (1.0 to <2.0, n = 63, 46.3%), or good (≥2.0, n = 48, 35.3%). Factors associated with poor vascular reactivity included older age (p = 0.026), elevated serum blood urea nitrogen (p = 0.020), serum creatinine (p = 0.021), urine protein-to-creatinine ratio (UPCR, p = 0.013), and myostatin levels (p = 0.003), along with reduced estimated glomerular filtration rate (p = 0.015). Multivariate regression analysis identified older age, higher serum creatinine, and log-transformed myostatin levels as significant independent predictors of lower VRI. CONCLUSIONS: These findings suggest that myostatin may serve as a potential biomarker for endothelial dysfunction in CKD patients. Future large-scale, longitudinal studies are warranted to confirm and extend our preliminary findings.