Impact of Acute Antioxidant Administration on Inflammation and Vascular Function in Heart Failure with Preserved Ejection Fraction.

Abstract

BACKGROUND\nWhile it is now well established that heart failure with preserved ejection fraction (HFpEF) is associated with marked inflammation and a pro-oxidant state that is accompanied by vascular dysfunction, whether acute antioxidant (AO) administration can effectively target these disease-related decrements has not been evaluated. Thus, the present study sought to evaluate the efficacy of an over-the-counter AO cocktail (600mg alpha lipoic acid, 1,000mg Vitamin C, and 600IU vitamin E) to acutely mitigate inflammation and oxidative stress, and subsequently improve nitric oxide (NO) bioavailability and vascular function, in patients with HFpEF.\n\n\nMETHODS\nFlow mediated dilation (FMD) and reactive hyperemia (RH) were evaluated to assess conduit vessel and microvascular function, respectively, following administration of either placebo (PL) or AO in 16 patients with HFpEF (73±10yrs) using a double-blind, crossover design. Circulating biomarkers of inflammation (C-reactive protein, CRP), oxidative stress (Malondialdehyde and Protein Carbonyl), free radical concentration (EPR Spectroscopy), antioxidant capacity, ascorbate and NO bioavailability (plasma nitrate, NO3-, and nitrite, NO2-) were also assessed.\n\n\nRESULTS\nFMD improved following AO administration (PL: 3.49±0.7%, AO: 5.83±1.0%), while RH responses were similar between conditions (PL: 428±51ml, AO: 425±51ml). AO administration decreased CRP (PL: 4429±705ng/ml, AO: 3664±520ng/ml) and increased ascorbate (PL: 30.0±2.9µg/ml, AO: 45.1±3.7µg/ml) and NO2- (PL: 182±21nM, AO: 213±24nM), but did not affect other biomarkers.\n\n\nCONCLUSION\nTogether, these data suggest acute AO administration can exert anti-inflammatory effects and improve conduit artery vasodilation, but not microvascular function, in patients with HFpEF.