Hepatic expression and serum levels of syndecan 1 (CD138) in patients with nonalcoholic fatty liver disease

Abstract

Background and aims. Syndecan-1 (CD138) is a transmembrane heparan sulfate proteoglycan expressed in the liver which may exert metabolic effects by mediating the hepatic clearance of triglyceride-rich lipoproteins. In the present study, we assayed serum levels and the hepatic expression of syndecan-1 and examined their association with clinical, biochemical, and histologic phenotypes in patients with histology-proven nonalcoholic fatty liver disease (NAFLD). Methods. A total of 59 patients with biopsy-proven NAFLD and 54 matched controls were enrolled. The analysis of syndecan-1 expression in liver biopsies was performed by immunohistochemistry on formalin-fixed, paraffin-embedded samples. Serum syndecan-1 levels were measured by ELISA. Results. NAFLD patients had significantly higher serum syndecan-1 levels [median: 61 ng/mL (interquartile range: 36–97 ng/mL)] than controls [median: 37 ng/mL (interquartile range: 25–59 ng/mL, Mann–Whitney U test, p < 0.001]. However, we did not find any significant association between serum syndecan-1 and the mean syndecan-1 immunohistochemical score (n = 59, r = 0.064, p = 0.63). Interestingly, the syndecan-1 immunohistochemical score was an independent predictor of HDL cholesterol in NAFLD patients (β = 0.27; t = 1.99, p < 0.05). Conclusions. Our data suggest that serum syndecan-1 levels are raised in patients with NAFLD. Moreover, the syndecan-1 immunohistochemical score in the liver is independently associated with HDL cholesterol in this group of patients. These pilot results support further investigation of this molecule in metabolic liver diseases.

Key Words::

• enzyme-linked immunosorbent assay
• immunohistochemistry
• nonalcoholic fatty liver disease
• syndecan-1

Acknowledgements

This study was financially supported by a grant from the Institute of Gastroenterology, Marmara University, Istanbul, Turkey. The authors report no conflicts of interest.

Declaration of interest: The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.