The Interaction Between Inorganic Nitrate Supplementation and Metformin on Exercise Capacity, Vascular Function, and Insulin Sensitivity in Individuals With Pre-Diabetes
University of Virginia
Summary
This study is examining whether short-term supplementation with inorganic nitrate, in the form of beetroot juice, can enhance blood vessel health, insulin sensitivity, and exercise capacity in individuals with prediabetes. We will be comparing the responses in individuals who are taking metformin to those who are naive to metformin. The results from this study may help identify non-pharmacological interventions in prediabetes.
Description
One in 10 Americans have diabetes, with \~ 95% having type 2 diabetes (T2D). Another 1 in 3 have prediabetes, with 70% developing T2D during their lifetimes. Exercise is the standard of care for T2D. However, responses to exercise are blunted in T2D, in part due to the widespread use of metformin, which may inhibit mitochondrial function. Alternative therapies, such as inorganic nitrate supplementation, may provide benefits without attenuating exercise responses. Purpose: To examine inorganic nitrate supplementation on exercise tolerance, vascular function, and insulin sensitivity in subjects…
Eligibility
- Age range
- 18–60 years
- Sex
- All
- Healthy volunteers
- No
Inclusion Criteria: * Individuals who can communicate meaningfully with the investigator and can provide written consent. * Confirmed prediabetic individuals (ages 18-60 years old) (2-hour glucose of 140-199 mg/dL following OGTT test or HbA1c between 5.7-6.4% tested on two occasions within 6 months). * Taking metformin (stable dose for at least a week) or naïve to metformin * Sedentary (\<1 day/week of structured exercise) * Be able to perform exercise on a cycle ergometer without assistance * Stable medication regimen for the last 6 months * If female, have a normal menstrual cycle Exclusio…
Interventions
- Dietary SupplementDietary Supplement: Inorganic Nitrate (Beetroot juice)
Participants will be supplemented with inorganic nitrate in the form of beetroot juice for 4 days (12.9 mmol of NO3/day), and their vascular health, insulin sensitivity, and exercise capacity will be measured post-supplementation. This is a randomized crossover design with 2 parallel groups (Group 1: Currently taking metformin, Group 2: Naive to metformin).
- Dietary SupplementDietary supplement: Placebo (Nitrate-depleted beetroot juice)
Participants will be supplemented with nitrate-depleted beetroot juice for 4 days (\<0.01 mmol NO3/day), and their vascular health, insulin sensitivity, and exercise capacity will be measured post-supplementation. This is a randomized crossover design with 2 parallel groups (Group 1: Currently taking metformin, Group 2: Naive to metformin).
Location
- University of VirginiaCharlottesville, Virginia