433-P: Syndecan-1, a Marker of Endothelial Glycocalyx Degradation, Is Associated with Albuminuria in Type 2 Diabetes Free

The endothelial glycocalyx (EG) covers the luminal surface of vascular endothelium and is involved in various functions of endothelium including the microvascular permeability. Syndecan (SDC)-1 is a transmembrane heparan sulfate proteoglycan and is a major component of EG. Since the extracellular domain of SDC-1 is shed by inflammatory mediators, increased circulating levels of SDC-1 is considered as a marker of EG degradation. No study has thus far investigated the relationship between EG degradation and albuminuria in type 2 diabetes. This study aimed to investigate the association between EG degradation assessed by serum SDC-1 levels and urinary albumin to creatinine ratio (ACR) in type 2 diabetes. This study enrolled 370 Japanese patients with type 2 diabetes (T2D) and 219 nondiabetic controls (ND). Patients with severe kidney dysfunction whose estimate glomerular filtration rate (eGFR) was less than 30 mL/min/1.73m² were excluded. T2D patients were divided into normoalbuminuria (A1), microalbuminuria (A2) and macroalbuminuria (A3) by ACR. Median value of serum SDC-1 levels in T2D with A1 stage was 24.5 ng/mL which was higher than that in ND (16.0 ng/mL) (p <0.001). Median values of SDC-1 in T2D with A2 and A3 stages were 29.0 and 38.7 ng/mL, respectively, which were significantly different among albuminuria stages (p <0.001). First, multivariate analysis including T2D patients with A1 stage and ND revealed that the presence of T2D was independently associated with serum SDC-1 level (β = 0.356, p <0.001). Next, multivariate analysis in T2D patients with all albuminuria stages revealed that serum SDC-1 level was independently associated with ACR (β = 0.121, p = 0.012) after adjustment for known other risk factors for albuminuria. In conclusion, serum SDC-1 level is increased in T2D compared to ND and is an independent determinant of ACR in T2D patients. This study suggests a potential involvement of the EG degradation in albuminuria in T2D.