Enhanced syndecan-1 expression on neutrophils in patients with type 2 diabetes mellitus

The peripheral neutrophils are one of the main inflammatory cells and significantly influence the damage of endothelium. Type 2 diabetes is a manifestation of an ongoing low-grade inflammation. In diabetes, impairment of neutrophil adhesion to the endothelium and migration to the site of inflammation were detected, which associated closely with adhesion molecules expressed on neutrophils and endothelial cells. To detect the expression of syndecan-1 on neutrophils in patients with type 2 diabetes mellitus, we recruited 29 patients with type 2 diabetes mellitus without any diabetic complication and 24 healthy subjects (controls). Expression of syndecan-1 was determined by flow cytometry, and potential correlations between syndecan-1 and clinical characteristics were analyzed. On neutrophils, percentage of positive syndecan-1 cells was significantly higher in subjects with diabetes (10.363 ± 1.689%) than that of the controls (3.775 ± 0.634%, P = 0.001). An association between body mass index (BMI) and percentage of positive syndecan-1 neutrophils was detected (r = 0.415, P = 0.025). When BMI was categorized into subgroups of ≤25 kg/m(2) (n = 10) and >25 kg/m(2) (n = 19), the average percentages of positive syndecan-1 neutrophils in patients with diabetes were 5.733 ± 1.842% and 12.642 ± 2.251%, respectively (t = -2.137, P = 0.042). A multiple regression analysis showed that BMI (β = 0.783, P < 0.000) was a significant predictor of positive syndecan-1 neutrophils in subjects with type 2 diabetes.