Aim: Prescription eicosapentaenoic acid (EPA) reduced cardiovascular events in the REDUCE-IT study population, including patients with diabetes. As EPA has been previously shown to reduce LDL oxidation, we investigated if it may prevent HDL oxidation at a pharmacologic dose. Atheroprotective properties of HDL are compromised in patients with diabetes due to oxidative damage and glycation.

Methods: Isolated human HDL at 200 µg/mL was incubated with vehicle or EPA at levels that match plasma concentrations (∼10 µM) at 4 g/d. All samples were subjected to oxidation over 6 hour under low and high glucose (200 mg/dL) conditions.

Results: EPA inhibited HDL oxidation in a highly dose- and time-dependent manner. At lower concentrations (≤ 3.5 µM), EPA inhibited oxidation until 4 hour or less. At higher concentrations (>7.0 µM), EPA inhibited HDL oxidation 6 hour. At 10.0 µM, EPA inhibited HDL oxidation by 80% (p<0.001) at 6 hour. Large effect shifts were observed with relatively small concentration shifts, with the critical concentration shifts being time-dependent. Similar antioxidant effects were observed with hyperglycemia.

Conclusions: These data support concentration-dependent antioxidant effects for EPA that require pharmacologic concentrations for sustained activity. These effects of EPA may provide one potential mechanism for cardiovascular benefits in patients with diabetes.
Disclosure

S. Sherratt: None. R. Mason: Consultant; Self; Amarin Corporation. Research Support; Self; Amarin Corporation, Amgen Inc., Novartis AG, Pfizer Inc. Speaker's Bureau; Self; Pfizer Inc.

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