Maqui berry standardized extract (e.g. Delphinol®) has been used with success to modulate blood glucose and associated variables at a dosage of 450mg daily. Lower dosages have also been used with favorable effects. However, it is unknown what dosage is optimal for positively impacting vascular function. The purpose of this study is to determine the impact of Maqui berry standardized extract (e.g. Delphinol®) at varying dosages on vascular function assessed using the perfusion index, Vendys, and blood nitrate/nitrite concentrations.

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.

• age 18-35 years
• male or female
• body mass index (BMI) between 18-29.9 kg/m2 (not obese)
• non-smoker
• no diagnosed history of diabetes
• no diagnosed history of cardiovascular disease including any vascular disease
• no diagnosed history of neurological disease
• no consumption of alcohol or fruit within 48 hours of testing
• no consumption of caffeine-containing beverages within at least 48 hours of testing
• 12-lead ECG without significant heart rate and rhythm abnormalities and blood glucose within normal limits (as reviewed by Tara Hunter, BSN and confirmed by Dr. John Hyden, MD as needed)
• if female, not be pregnant

Double-blinded