The Effect of Omega-3 Fatty Acids on Serum Apelin Levels in Cardiovascular Disease: A Randomized, Double-Blind, Placebo-Controlled Trial

Background: Cardiovascular disease (CVD) is the leading cause of mortality worldwide. Omega-3 fatty acids have been shown to have both anti-atherogenic and anti-inflammatory effects through inducing the expression and production of adipokines. Adipokines such as apelin, have been observed to play a protective role in the incidence and progression of CVD. The aim of this study was to assess the influence of omega-3 fatty acids supplementation on the serum apelin levels in patients with cardiovascular disease. Methods: Forty-six male patients with CVD participated in the study. Patients were randomly allocated into two groups receiving either omega-3 fatty acids or a placebo. Participants received 4 g of omega-3 fatty acids (EPA: 720 mg, DHA: 480 mg) or a placebo (edible paraffin) for 8 weeks. Serum apelin levels, high sensitive C-reactive protein (hs-CRP), and lipid profiles were measured. Dietary intake, anthropometric parameters, body composition, systolic and diastolic blood pressure were evaluated before and after the 8 weeks of intervention. Statistical analyses were performed using SPSS version 22. Results: Two participants from the placebo group withdrew from the study. Prior to the intervention, no significant differences were present between the two groups in age, body mass index, body composition, dietary intakes, lipid profiles and blood pressure. Compared to placebo, the intake of omega-3 fatty acids increased serum apelin levels (p= 0.018), decreased the levels of LDL cholesterol, and decreased serum hs-CRP concentrations (p= 0.007, p= 0.011 respectively). Additionally, the concentrations of VLDL, TG and hs-CRP (p= 0.037, p= 0.037 and p= 0.016 respectively) declined compared to baseline and final values in the omega-3 fatty acids group. Conclusions: Omega-3 fatty acid supplementation increases serum apelin and HDL concentrations, while decreasing serum LDL-C and hs-CRP levels.