The Effects of Oral Inorganic Nitrate Supplementation on Lower Limb Perfusion During Exercise in Patients With PAD

Summary

Peripheral arterial disease (PAD) is a highly prevalent and costly condition. Intermittent claudication (IC), defined as ischemic leg pain that occurs with walking, results in functional impairment, reduced daily physical activity, and a lower quality of life. Although the mechanisms contributing to functional impairment are not fully delineated, current evidence suggests that the uncoupling of skeletal muscle cellular metabolism from tissue perfusion may be responsible for exercise intolerance. We have previously shown increases in plasma inorganic nitrite, via oral nitrate, produced clinically significant increases exercise performance in patients with PAD+IC. The hypothesis of this proposal is in patients with PAD+IC, 3-6 days of oral dietary nitrate consumption (in the form of concentrated beetroot juice) will produce a greater tissue perfusion, oxygen delivery, and enhanced muscle metabolism in comparison to placebo. This will translate into an increase in physical performance in both muscle specific plantar flexion exercise and treadmill measures of pain free ambulation. In order to test this hypothesis, we will recruit 10 patients PAD+IC in a randomized, double-blind, placebo controlled, cross over design.

Timeline

Start

2020-02-01

Primary completion

2024-12

Completion

2024-12

Publications

• Background Isbell DC, Epstein FH, Zhong X, DiMaria JM, Berr SS, Meyer CH, Rogers WJ, Harthun NL, Hagspiel KD, Weltman A, Kramer CM. Calf muscle perfusion at peak exercise in peripheral arterial disease: measurement by first-pass contrast-enhanced magnetic resonance imaging. J Magn Reson Imaging. 2007 May;25(5):1013-20. doi: 10.1002/jmri.20899.
• Background Isbell DC, Berr SS, Toledano AY, Epstein FH, Meyer CH, Rogers WJ, Harthun NL, Hagspiel KD, Weltman A, Kramer CM. Delayed calf muscle phosphocreatine recovery after exercise identifies peripheral arterial disease. J Am Coll Cardiol. 2006 Jun 6;47(11):2289-95. doi: 10.1016/j.jacc.2005.12.069. Epub 2006 May 15.
• Background Lopez D, Pollak AW, Meyer CH, Epstein FH, Zhao L, Pesch AJ, Jiji R, Kay JR, DiMaria JM, Christopher JM, Kramer CM. Arterial spin labeling perfusion cardiovascular magnetic resonance of the calf in peripheral arterial disease: cuff occlusion hyperemia vs exercise. J Cardiovasc Magn Reson. 2015 Feb 22;17(1):23. doi: 10.1186/s12968-015-0128-y.
• Background Kenjale AA, Ham KL, Stabler T, Robbins JL, Johnson JL, Vanbruggen M, Privette G, Yim E, Kraus WE, Allen JD. Dietary nitrate supplementation enhances exercise performance in peripheral arterial disease. J Appl Physiol (1985). 2011 Jun;110(6):1582-91. doi: 10.1152/japplphysiol.00071.2011. Epub 2011 Mar 31.

Drugs

Indications