The effect of dietary nitrate on exercise capacity in chronic kidney disease: a randomized controlled pilot study.
Nitric Oxide
; 106: 17-23, 2021 01 01.
Article
in En
| MEDLINE
| ID: mdl-33080411
ABSTRACT
BACKGROUND:
Chronic Kidney Disease (CKD) patients exhibit a reduced exercise capacity that impacts quality of life. Dietary nitrate supplementation has been shown to have favorable effects on exercise capacity in disease populations by reducing the oxygen cost of exercise. This study investigated whether dietary nitrates would acutely improve exercise capacity in CKD patients. METHODS ANDRESULTS:
In this randomized, double-blinded crossover study, 12 Stage 3-4 CKD patients (Mean ± SEM Age, 60 ± 5yrs; eGFR, 50.3 ± 4.6 ml/min/1.73 m2) received an acute dose of 12.6 mmol of dietary nitrate in the form of concentrated beetroot juice (BRJ) and a nitrate depleted placebo (PLA). Skeletal muscle mitochondrial oxidative function was assessed using near-infrared spectroscopy. Cardiopulmonary exercise testing was performed on a cycle ergometer, with intensity increased by 25 W every 3 min until volitional fatigue. Plasma nitric oxide (NO) metabolites (NOm; nitrate, nitrite, low molecular weight S-nitrosothiols, and metal bound NO) were determined by gas-phase chemiluminescence. Plasma NOm values were significantly increased following BRJ (BRJ vs. PLA 1074.4 ± 120.4 µM vs. 28.4 ± 6.6 µM, p < 0.001). Total work performed (44.4 ± 10.6 vs 39.6 ± 9.9 kJ, p = 0.03) and total exercise time (674 ± 85 vs 627 ± 86s, p = 0.04) were significantly greater following BRJ. Oxygen consumption at the ventilatory threshold was also improved by BRJ (0.90 ± 0.08 vs. 0.74 ± 0.06 L/min, p = 0.04). These changes occurred in the absence of improved skeletal muscle mitochondrial oxidative capacity (p = 0.52) and VO2peak (p = 0.35).CONCLUSIONS:
Our findings demonstrate that inorganic nitrate can acutely improve exercise capacity in CKD patients. The effects of chronic nitrate supplementation on CKD related exercise intolerance should be investigated in future studies.Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Exercise Tolerance
/
Renal Insufficiency, Chronic
/
Nitrates
Type of study:
Clinical_trials
Aspects:
Patient_preference
Limits:
Adult
/
Aged
/
Female
/
Humans
/
Male
/
Middle aged
Language:
En
Journal:
Nitric Oxide
Journal subject:
BIOQUIMICA
/
QUIMICA
Year:
2021
Document type:
Article
Affiliation country:
United States