The role of endocan and selected pro-inflammatory cytokines in systemic lupus erythematosus

Introduction
Systemic lupus erythematosus (SLE) is a multisystem inflammatory autoimmune disease with a wide spectrum of clinical manifestations. Cytokines such as interleukin-1 (IL-1) and tumour necrosis factor α (TNF-α) are involved in its pathogenesis. Endocan is a novel marker of endothelial dysfunction and is likely to be engaged in proinflammatory processes in SLE.

Aim
To determine whether endocan serum concentration in SLE patients vary from healthy controls.

Material and methods
The study included 36 patients with SLE. SLEDAI-2K score was used to assess disease activity. The control group comprised 23 healthy volunteers. ELISA kits were used to assess serum concentrations of endocan, IL-1β, TNF-α, vascular endothelial growth factor (VEGF) and high-sensitivity C reactive protein (hs-CRP).

Results
The serum concentration of endocan was significantly higher (p < 0.001) in the SLE group than in healthy individuals. A positive correlation was found between serum levels of endocan and IL-1β (r = 0.47, p < 0.05). Active SLE patients (SLEDAI-2K score above 6 points) with an elevated total cholesterol level (above 5.17 mmol/l) were found to have VEGF concentration higher than those with a normal cholesterol level (p < 0.03). No other relevant relationships were found between the serum concentration of endocan, other laboratory parameters, anthropometric features, activity and duration of SLE.

Conclusions
A higher serum level of endocan in SLE patients indicates its possible role in the pathogenesis of the disease and reflects endothelial dysfunction. Our findings indicate that endocan could serve as a potential marker of endothelial dysfunction in SLE.