Association between Tubular Injury Biomarkers and Early Renal Injury in Hypertensive Patients

The lack of uniform diagnostic criteria and effective biomarkers for hypertensive nephrosclerosis makes early detection challenging. This study aimed to explore renal dysfunction biomarkers in hypertensive patients to identify early renal injury.The current study enrolled 106 hypertensive patients divided into 3 groups according to their urine microalbumin/creatinine ratio (ACR) to investigate the association between tubular injury biomarkers and early renal impairment. The serum levels of human and animal models were measured by ELISA, and the statistical analysis was conducted by SPSS. The degree of renal injury was assessed by histological staining.Serum levels of kidney injury molecule-1 (KIM-1) and insulin-like growth factor-binding protein 7 (IGFBP-7) correlated with renal function in hypertensive patients. Moreover, the area under the curve (AUC) for Kim-1 and IGFBP-7 remained greater than 0.6 in detecting nephron injury. In spontaneously hypertensive rats (SHR), serum KIM-1 and IGFBP-7 increased markedly in 12-week-old SHR compared with 8-week-old SHR and Wistar-Kyoto (WKY) rats, while serum creatinine (SCr) and blood urea nitrogen (BUN) were upregulated with no significance at the same time point.Our findings suggest that serum levels of KIM-1 and IGFBP-7 may serve as more sensitive biomarkers for early renal injury in hypertensive nephropathy than conventional biomarkers. Identification of the relationship between tubular injury biomarkers and hypertensive nephropathy offers novel insights into the potential use of biomarkers for cardiorenal syndrome as well as the management of hypertensive patients.