Assessment of Delphinol® Dose on Vascular Function

Antioxidant compounds have been well-studied in relation to surrogate measures of overall health, with a particular impact on the function of blood vessels. Delphinol® is a botanical agent (an extract of maqui berries) with antioxidant properties primarily owing to its high anthocyanin content. Delphinol® has excellent bioavailability, as demonstrated recently. Acute and chronic anthocyanin consumption has demonstrated the ability to improve vascular reactivity assessed via flow-mediated dilation and pulse wave velocity across a range of dosages . Antioxidant compounds have also been reported to favorably impact nitric oxide, often estimated using the surrogate measure of blood nitrate/nitrite. In a previous study using Delphinol® at various dosages, Delphinol® significantly and dose-dependently improved glucose homeostasis acutely, with noted lowering of blood glucose and lipids. The mechanism of action for this effect appears related to a novel sodium glucose cotransporter inhibition . This favorable effect on glucose and lipid metabolism is an effect that some have suggested may be associated with the protection of vascular function. A dosage of 450mg of Delphinol® daily has resulted in improvements in oxidative stress markers, another factor that can potentially contribute to vascular homeostasis. Together, these studies suggest Delphinol® may influence vascular function; however, no studies have directly determined this in human subjects. Though similar studies exist demonstrating anthocyanin consumption resulting in improvements in vascular function, none to date have investigated different doses of a maqui extract on vascular function as assessed using the digital thermal monitoring of reperfusion. Digital thermal monitoring is suggested to be a more reliable measure of vascular function because it removes the sonographer variability; that is, accurately capturing the brachial artery with an ultrasound transducer can be very challenging. The aim of the present study is to determine the impact of Delphinol® at varying dosages on vascular function assessed using the perfusion index, Vendys II (a tool to measure endothelial vascular function via digital thermal monitoring), and blood nitrate/nitrite concentrations in men and women. While it may be logical to assume that the higher dosage may provide a more robust overall effect with regards to our outcome measures, we will maintain a conservative non-directional hypothesis related to dose. That said, we do hypothesize that all doses of the ingredient will result in small improvements in the measured vascular indices.