Introduction:
Dyslipidemia is a prevalent condition in obesity and type 2 diabetes. Although fish oil rich in omega-3 fatty acids (ω-3) is a widely used hypolipidemic agent, it is often required at high doses. At high doses, these fatty acids can induce oxidative stress or endothelial activation and therefore, strategies to improve their beneficial effects are needed. We previously reported that fish oil in combination with cyclooxygenase (COX) inhibitors exerts enhanced hypolipidemic and anti-inflammatory effects in low density lipoprotein receptor knock-out mice. Here, we sought to determine the effects of ω-3 fatty acids in combination with naproxen (NX), a COX inhibitor, on dyslipidemia and gene expression in subcutaneous adipose tissue (scAT) in humans.
Methods:
Obese dyslipidemic patients were randomly assigned to receive one of these interventions (n=8/group) for 12 wk: 1) Standard nutrition counseling (control), 2) ω-3 (2 g twice daily), 3) NX (220 mg twice daily), and 4) ω-3 (2 g twice daily) + NX (220 mg twice daily).
Results:
The body mass index, HOMA-IR, and plasma total, LDL, and HDL cholesterol levels were not altered significantly in any of the groups. The percent change in plasma
triglycerides (TG) from baseline was 75% (
P
<0.1) and 68% (
P
<0.05) in ω-3 and ω3 + NX-treated subjects, respectively. Notably, 25% of subjects who received ω-3s alone did not show a reduction in TG whereas all the patients that received ω-3 + NX showed a reduction in TG. Realtime PCR analysis of scAT showed that the expression of glucose transporter 4 (GLUT-4), a marker of glucose uptake and a key regulator of glucose homeostasis was significantly reduced in ω-3 compared to control group (
P
<0.01). However, combining NX with ω-3 abolished this effect. Moreover, the expression of MCP-1 and VCAM-1, markers of inflammatory response or endothelial activation, was significantly increased in ω-3 but not in ω-3 + NX group. The plasma levels of MCP-1 and E-selectin did not vary significantly in any of the groups.
Conclusions:
Our data reveal previously unrecognized effects of fish oil in scAT. Our data suggest that combining NX with ω-3 fatty acids will increase their effectiveness in reducing plasma TG and improve the benefits of ω-3 supplements by favorably altering gene expression in scAT.