Is there a link between CD146, a novel adhesion molecule and other markers of endothelial dysfunction in nephrotic syndrome and continuous ambulatory peritoneal dialysis?

Soluble Vascular Cell Adhesion Molecule-1 Is Associated With Disease Activity in Adult-Onset Minimal Change Disease

BACKGROUND

Cell adhesion molecules have been documented to be elevated in numerous immune inflammatory diseases. Minimal change disease (MCD) is an immune disorder. This study aimed to evaluate whether levels of soluble vascular cell adhesion molecule-1 (sVCAM-1) and soluble E-selectin (sE-selectin) reflect disease activity in adult-onset MCD.

METHODS

A sandwich enzyme-linked immunosorbent assay was used to measure the soluble adhesion molecules in 40 patients with nephrotic-range proteinuria and biopsy-proven MCD, obtained at the time of diagnosis and during remission. Thirty-five age- and sex-matched healthy volunteers served as controls.

RESULTS

Patients with MCD during the active stage showed significantly higher levels of sVCAM-1 and sE-selectin when compared to controls. Moreover, sVCAM-1 had significantly positive correlations with both urine protein and serum cholesterol, and was negatively associated with serum albumin. Multiple analyses showed that serum albumin was an independent predictor of sVCAM-1. The correlations between sE-selectin and other clinical parameters were not statistically significant. At follow-up, these markers systematically decreased as the disease went into remission, but the increase in sVCAM-1 persisted even in patients obtaining complete remission for 6 months.

CONCLUSIONS

Patients with active MCD had increased levels of sVCAM-1 and sE-selectin. The correlation between sVCAM-1 and proteinuria, serum albumin and cholesterol and its decline during remission indicate that sVCAM-1 is associated with disease activity.

Biomarkers of endothelial dysfunction in patients with primary focal segmental glomerulosclerosis

AIM

Endothelial dysfunction occurs in nephrotic syndrome (NS) and may constitute a link between NS and vascular complications. Focal segmental glomerulosclerosis (FSGS) is a common cause of NS. This study aimed to assess endothelial markers at different stages of FSGS and define whether they were associated with thromboembolic complications and disease activity.

METHODS

Forty-four patients with nephrotic-range proteinuria and biopsy-proven primary FSGS were included in this study. Nine of them had concurrent thromboembolisms. Thirty-two sex- and age- matched healthy volunteers served as controls. Endothelial markers including circulating endothelial cells (CECs), soluble thrombomodulin (sTM), von Willebrand factor (vWf), soluble vascular cell adhesion molecule-1 (sVCAM-1) and sE-selectin were assessed at the commencement of the study in all participants and were repeated at 2, 6 and 12 months of follow-up in patients without thromboembolisms.

RESULTS

Patients with FSGS during active stage showed significantly higher levels of CECs, sTM, vWf, sVCAM-1 and sE-selectin when compared with controls. Moreover, patients with thromboembolisms had higher CECs and vWf than those without thromboembolisms. In patients without thromboembolisms, endothelial markers except sE-selectin had inverse correlations with serum albumin and were positively related to cholesterol. Multiple analyses showed that cholesterol and serum albumin were independent predictors of CECs and sTM, and vWf and sVCAM-1, respectively. At follow-up, these markers systematically decreased as the disease went into remission, but the increase in vWf and sVCAM-1 persisted even in patients obtaining complete remission for nearly a year. In patients with no response, levels of endothelial markers exhibited no obvious change.

CONCLUSION

Patients with FSGS had elevated markers of endothelial dysfunction, which were largely related to the activity of the disease. Meanwhile, levels of CECs and vWf were higher in patients concurrent with thromboembolisms.

Increased plasma adiponectin closely associates with vascular endothelial dysfunction in type 2 diabetic patients with diabetic nephropathy

Several studies found that adiponectin, an adipokine withstands atherosclerosis in vivo, is significantly increased in subjects with diabetic nephropathy (DN), but its clinical meaning remains unclear. For its structural similarity to complement C1q and collagen, we performed this study to explore the relationship between adiponectin and the vascular endothelial function alterations in DN patients. 50 type 2 diabetic patients without clinical cardiovascular complications were assigned to control group, microalbuminuria group (Micro-MA), and macroalbuminuria group (Macro-MA) according to the Mogensen's criteria. Plasma adiponectin and soluble vascular cell adhesion molecule-1 (sVCAM-1) were detected. Flow-mediated dilatation (FMD), nitroglycerin-induced dilatation (NID) and cardiologic parameters were measured by ultrasound cardiogram. Plasma adiponectin level was significantly and gradually increased in agreement with the amount of urine albumin excretion. sVCAM-1 was higher in Micro-MA and Macro-MA patients than in the controls, but it was comparable between the former 2 groups. FMD and NID were both remarkably decreased in Macro-MA group compared with Micro-MA and control group. For the whole subjects, plasma adiponectin was negatively related to FMD (r=-0.397, P<0.01) and NID (r=-0.413, P<0.01). These results suggest that increased plasma adiponectin may predict co-existing vascular endothelial dysfunction in DN patients.

Hyperuricemia is a mediator of endothelial dysfunction and inflammation in renal allograft recipients

BACKGROUND

Hyperuricemia is common in renal transplant recipients treated with calcineurin inhibitors. Uric acid induces glomerular hypertension, microvascular disease, and renal interstitial fibrosis and is an independent risk factor for cardiovascular complications. The mechanisms by which uric acid injures renal allografts and the cardiovascular system remain unclear.

OBJECTIVE

To assess the influence of uric acid on biomarkers of endothelial dysfunction and inflammation in renal allograft recipients.

PATIENTS AND METHODS

The study included 78 allograft recipients with normal allograft function. Exclusion criteria were abnormal renal function, proteinuria, diabetes mellitus, obesity, and inflammation. Participants were divided into 2 groups: 48 patients with hyperuricemia (mean [SD] uric acid concentration, 7.72 [1.33] mg/dL) and 30 patients with normouricemia (5.48 [0.92] mg/dL; control group). Concentrations of plasma resistin, CD146, and soluble vascular cell adhesion molecule-1 (sVCAM-1), which are markers of endothelial dysfunction and inflammation, were assessed in both groups. No significant differences were noted for patient demographic data including age, sex, cause of renal failure, number of HLA mismatches, delayed graft function, and number of acute rejection episodes.

RESULTS

Concentrations of the examined biomarkers were increased in the group with hyperuricemia compared with the control group: plasma resistin, 7.15 (2.42) ng/mL vs 6.29 (2.76) ng/mL; CD146, 389.7 (150.0) microg/mL vs 330 (117) microg/mL; and sVCAM-1, 1126 (371) ng/mL vs 955 (269) ng/mL (P < .03). In addition, resistin correlated significantly with sVCAM-1 (P < .01).

CONCLUSIONS

Hyperuricemia mediates endothelial dysfunction and inflammation and via this pathway, possibly contributes to chronic allograft injury and cardiovascular events in renal allograft recipients.

Markers of endothelial cell activation/injury: CD146 and thrombomodulin are related to adiponectin in kidney allograft recipients

BACKGROUND

Adiponectin may be used for assessing the risk of coronary artery disease (CAD) and may be related to the development of acute coronary syndrome. Decreased adiponectin has been associated with some risk factors for cardiovascular diseases such as male sex, obesity and diabetes mellitus. Adiponectin has antiatherogenic properties and attenuates endothelial inflammatory responses. CD146, a novel cell adhesion molecule, is localized at the endothelial junction. In kidney allograft recipients, endothelial dysfunction and atherosclerosis are almost universal. The aim of this cross-sectional study was to evaluate possible relations between adiponectin, CD146, and other markers of endothelial cell injury in 82 stable kidney transplant recipients (mean age 45 years, mean time after transplantation 47 months) with and without CAD.

METHODS

Adiponectin and markers of endothelial injury: CD146, von Willebrand factor, thrombomodulin, ICAM, CD40L, P-selectin and other hemostatic markers were assessed using commercially available kits.

RESULTS

Patients with CAD had evidence of more pronounced endothelial dysfunction, procoagulant state and lower adiponectin than patients without CAD. Adiponectin correlated significantly, in univariate analysis, with CD146 (r = 0.29, p = 0.009), thrombomodulin (r = 0.37, p = 0.001), protein Z (r = -0.25, p = 0.03), BMI (r = -0.26, p = 0.047), serum creatinine (r = 0.26, p = 0.02) and urea (r = 0.38, p = 0.001). CD146 correlated significantly with von Willebrand factor (r = 0.33, p = 0.002), thrombomodulin (r = 0.25, p = 0.025), age (r = 0.34, p = 0.001), platelets (r = -0.33, p = 0.002), serum urea (r = 0.24, p = 0.039), cholesterol (r = 0.24, p = 0.046), ICAM (r = 0.23, p = 0.036), protein C activity (r = -0.26, p = 0.019) and tended to correlate with serum creatinine and time after transplantation. In multivariate linear regression, independent predictors of adiponectin were CD146, thrombomodulin and urea, and of CD146 was mainly age of patients.

CONCLUSIONS

Endothelial dysfunction and procoagulant state are more pronounced in kidney transplant recipients with CAD, particularly in those with lower GFR. In kidney transplant recipients, markers of endothelial cell injury are significantly increased relative to healthy volunteers. Elevation of adiponectin may be a defense mechanism against endothelial damage, reflected by elevated CD146 and thrombomodulin.