Background: Heart health benefits have been attributed to regular consumption of oats. Preclinical evidence suggests that a wild green oat extract (WGOE) may improve vasodilator function, but this is yet to be evaluated in humans.
Objective: To determine whether regular daily consumption of WGOE can influence vasodilator function in systemic and cerebral arteries.
Methods: Thirty-seven healthy older adults (>60 years) completed a 24-week randomized, double-blind, placebo-controlled two-way crossover dietary intervention with 1500 mg/day of encapsulated WGOE or placebo. All assessments were conducted at the end of each 12-week intervention arm, after participants had fasted for at least 4 h and at least 18 h after they had taken their last dose of supplement. Flow-mediated dilatation (FMD) of the brachial artery and hypercapnia-induced increases of blood flow in the middle cerebral artery were used to measure systemic and cerebral vasodilator responsiveness (CVR), respectively.
Results: Compared with placebo, WGOE supplementation increased CVR and FMD to a similar extent (42 and 41%, respectively, P < 0.01 for both). The improvements in CVR and FMD were not correlated. Resting blood pressure did not alter with supplementation. Dose and treatment duration were well tolerated by participants.
Conclusion: WGOE supplementation can improve vasodilator function in systemic and cerebral arteries, suggesting a potential role in the maintenance of cardiovascular health.
Nutritional Physiology Research Centre, University of South Australia, Adelaide, South Australia, Australia
Correspondence to Professor Peter Howe, Nutritional Physiology Research Centre, University of South Australia, GPO BOX 2471, Adelaide, SA 5001, Australia. Tel: +61 8 8302 1200; fax: +61 8 83022178; e-mail: email@example.com
Abbreviations: BP, blood pressure; FMD, flow-mediated dilatation; MCA, middle cerebral artery; NF-κB, nuclear factor kappa-B; TCD, transcranial Doppler; WGOE, wild green oat extract
Received 28 May, 2012
Revised 9 August, 2012
Accepted 4 October, 2012