1. Dietary nitrate does not reduce oxygen cost of exercise or improve muscle mitochondrial function in patients with mitochondrial myopathy
- Author
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Klaas Nicolay, Jeanine J. Prompers, Irenaeus F.M. de Coo, Carlijn M. P. le Clercq, Natal A. W. van Riel, Luc J. C. van Loon, Hubert J.M. Smeets, Joep P. J. Schmitz, Miranda Nabben, Stephan F. E. Praet, Harm R. Haak, Jolita Ciapaite, ACS - Microcirculation, Amsterdam Gastroenterology Endocrinology Metabolism, Experimental Vascular Medicine, Neurology, Rehabilitation Medicine, Moleculaire Genetica, RS: CARIM - R2.06 - Intermediate cardiac metabolism, RS: CAPHRI - R1 - Ageing and Long-Term Care, Interne Geneeskunde, RS: FHML MaCSBio, RS: GROW - R4 - Reproductive and Perinatal Medicine, RS: CARIM - R2.10 - Mitochondrial disease, Klinische Genetica, Bewegingswetenschappen, RS: NUTRIM - R3 - Respiratory & Age-related Health, RS: NUTRIM - HB/BW section A, RS: NUTRIM - R3 - Chronic inflammatory disease and wasting, and Computational Biology
- Subjects
0301 basic medicine ,Male ,P-magnetic resonance spectroscopy ,Mitochondrial Myopathies/drug therapy ,Physiology ,Administration, Oral ,Muscle Strength/drug effects ,Nitrate ,Oxygen ,SUPPLEMENTATION ,Oxygen Consumption/drug effects ,chemistry.chemical_compound ,0302 clinical medicine ,Mitochondrial myopathy ,Exercise Tolerance/drug effects ,Exercise Tolerance ,Permeabilized muscle fibers ,Mitochondrial Myopathies ,HUMAN SKELETAL-MUSCLE ,Middle Aged ,Nitrates/administration & dosage ,Mitochondria ,Treatment Outcome ,RESPIRATION ,Administration ,INORGANIC NITRATE ,Female ,medicine.symptom ,P-31-magnetic resonance spectroscopy ,Oral ,Adult ,medicine.medical_specialty ,EFFICIENCY ,VO ,chemistry.chemical_element ,Exercise intolerance ,Biology ,V̇o2peak ,Nitric oxide ,03 medical and health sciences ,Young Adult ,Oxygen Consumption ,Physiology (medical) ,Internal medicine ,31P-magnetic resonance spectroscopy ,Dietary Nitrate ,Respiration ,medicine ,Humans ,In patient ,O-2 COST ,Muscle/drug effects ,Muscle Strength ,Exercise ,Aged ,Nitrates ,NITRIC-OXIDE ,Muscle weakness ,(V) over dot(O2peak) ,CONSUMPTION ,medicine.disease ,Mitochondria, Muscle ,Mitochondria, Muscle/drug effects ,030104 developmental biology ,Endocrinology ,chemistry ,TIME-TRIAL PERFORMANCE ,Physical therapy ,Psychomotor Performance/drug effects ,Psychomotor Performance ,030217 neurology & neurosurgery - Abstract
Muscle weakness and exercise intolerance negatively affect the quality of life of patients with mitochondrial myopathy. Short-term dietary nitrate supplementation has been shown to improve exercise performance and reduce oxygen cost of exercise in healthy humans and trained athletes. We investigated whether 1 wk of dietary inorganic nitrate supplementation decreases the oxygen cost of exercise and improves mitochondrial function in patients with mitochondrial myopathy. Ten patients with mitochondrial myopathy (40 ± 5 yr, maximal whole body oxygen uptake = 21.2 ± 3.2 ml·min−1·kg body wt−1, maximal work load = 122 ± 26 W) received 8.5 mg·kg body wt−1·day−1inorganic nitrate (~7 mmol) for 8 days. Whole body oxygen consumption at 50% of the maximal work load, in vivo skeletal muscle oxidative capacity (evaluated from postexercise phosphocreatine recovery using31P-magnetic resonance spectroscopy), and ex vivo mitochondrial oxidative capacity in permeabilized skinned muscle fibers (measured with high-resolution respirometry) were determined before and after nitrate supplementation. Despite a sixfold increase in plasma nitrate levels, nitrate supplementation did not affect whole body oxygen cost during submaximal exercise. Additionally, no beneficial effects of nitrate were found on in vivo or ex vivo muscle mitochondrial oxidative capacity. This is the first time that the therapeutic potential of dietary nitrate for patients with mitochondrial myopathy was evaluated. We conclude that 1 wk of dietary nitrate supplementation does not reduce oxygen cost of exercise or improve mitochondrial function in the group of patients tested.
- Published
- 2017