Serum Apelin levels in psoriasis: A case-controlled prospective study

INTRODUCTION: Psoriasis is a chronic, inflammatory skin disease which is closely associated with obesity, cardiovascular diseases, diabetes and metabolic syndrome. Adipokines are a large of group bioactive substances secreted from adipose tissue which are involved in various metabolic diseases including psoriasis. Apelin is a very new described adipokine in this group.We aimed to evaluate the difference of serum apelin levels in patients with psoriasis vulgaris and healthy volunteers.
METHODS: Fourty volunteers and 37 patients with psoriasis vulgaris were recruited in this study. Healthy adults, with no known diagnosis of cancer, cardiovascular disease, diabetes mellitus, kidney failure and hematologic disorders were included in control group. Psoriasis was diagnosed according to physical and histopathological examination. Venous blood was collected into serum separate or tubes with clot activator. Biochemical analyses including fasting glucose, HOMA-IR, insulin, erythrocyte sedimentation rate, CRP, HbA1c, total cholesterol, LDL, HDL,TG were done. Serum fasting apelin concentration was measured with the ELISA assay.
RESULTS: The mean ages of participants of psoriasis were 43 years, and 23 male,14 female. The mean ages of a control group were 41 years,17 male and 23 female. There were no statistically significant differences between patient and control groups according to serum levels of total cholesterol, LDL, HDL, triglyceride, glucose, HbA1c, CRP, and erythrocyte. The mean value of serum apelin concentration in control and patient groups were 0.13 and 0.10 pg/mL, respectively, and there were statistically significant differences. Serum apelin concentration was only correlated with age. There was no correlation between serum apelin concentrations and other biochemical parameters and HOMA-IR values.
DISCUSSION AND CONCLUSION: Chronic inflammation of psoriasis induces hypoxia leading to adipose tissue dysfunction and adipose tissue fibrosis and may result in decreased release of anti-inflammatory adipokines such as apelin.