Cargando…

DIFFERENTIAL EFFECTS OF VARYING DOSES OF DIETARY NITRATE ON MUSCLE FUNCTION AND BLOOD PRESSURE IN OLDER SUBJECTS

We have recently demonstrated that dietary nitrate, a source of nitric oxide via the enterosalivary pathway, can improve muscle contractile function in healthy older men and women. Nitrate ingestion has also been shown to reduce blood pressure in older individuals. However, the optimal dose for elic...

Descripción completa

Detalles Bibliográficos
Autores principales: Coggan, Andrew R, Gallardo, Edgar, Gray, Derrick A, Hoffman, Richard, Moorthi, Ranjani
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Oxford University Press 2019
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6844768/
http://dx.doi.org/10.1093/geroni/igz038.320
_version_ 1783468506521534464
author Coggan, Andrew R
Gallardo, Edgar
Gray, Derrick A
Hoffman, Richard
Moorthi, Ranjani
author_facet Coggan, Andrew R
Gallardo, Edgar
Gray, Derrick A
Hoffman, Richard
Moorthi, Ranjani
author_sort Coggan, Andrew R
collection PubMed
description We have recently demonstrated that dietary nitrate, a source of nitric oxide via the enterosalivary pathway, can improve muscle contractile function in healthy older men and women. Nitrate ingestion has also been shown to reduce blood pressure in older individuals. However, the optimal dose for eliciting these beneficial effects is unknown. We therefore performed a randomized, double-blind, crossover study to determine the effects of ingesting 3.3 mL/kg of beetroot juice (BRJ) containing 0, 212, or 425 µmol/kg of nitrate in six healthy older (age 69±3 y) subjects. Maximal knee extensor speed (Vmax) and power (Pmax) were measured 2 h after BRJ ingestion using isokinetic dynamometry; blood pressure was monitored periodically throughout each study. Mean arterial pressure (in mmHg) was lower (P<0.05) after the high (80±4) vs. the low (84±3) or placebo (88±2) doses. Vmax (in rad/s), however, was higher (P<0.05) after the low dose (11.7±0.8), but not the high dose (10.8±1.0), compared to the placebo (10.5±1.0). Pmax (in W/kg) also tended to be higher (P=0.11) in the low (3.9±0.5) compared to the placebo (3.7±0.5) or high (3.7±0.5) trials. Five out of six subjects achieved a higher Vmax and Pmax after the low vs. the high dose. We conclude that dietary nitrate has differential effects on muscle function and blood pressure in older individuals. A high dose of nitrate intake further lowers blood pressure but does not enhance muscle contractility as much as a lower dose. Supported by Indiana University Purdue University Indianapolis and by the NIA (R21 AG053606)
format Online
Article
Text
id pubmed-6844768
institution National Center for Biotechnology Information
language English
publishDate 2019
publisher Oxford University Press
record_format MEDLINE/PubMed
spelling pubmed-68447682019-11-21 DIFFERENTIAL EFFECTS OF VARYING DOSES OF DIETARY NITRATE ON MUSCLE FUNCTION AND BLOOD PRESSURE IN OLDER SUBJECTS Coggan, Andrew R Gallardo, Edgar Gray, Derrick A Hoffman, Richard Moorthi, Ranjani Innov Aging Session 820 (Poster) We have recently demonstrated that dietary nitrate, a source of nitric oxide via the enterosalivary pathway, can improve muscle contractile function in healthy older men and women. Nitrate ingestion has also been shown to reduce blood pressure in older individuals. However, the optimal dose for eliciting these beneficial effects is unknown. We therefore performed a randomized, double-blind, crossover study to determine the effects of ingesting 3.3 mL/kg of beetroot juice (BRJ) containing 0, 212, or 425 µmol/kg of nitrate in six healthy older (age 69±3 y) subjects. Maximal knee extensor speed (Vmax) and power (Pmax) were measured 2 h after BRJ ingestion using isokinetic dynamometry; blood pressure was monitored periodically throughout each study. Mean arterial pressure (in mmHg) was lower (P<0.05) after the high (80±4) vs. the low (84±3) or placebo (88±2) doses. Vmax (in rad/s), however, was higher (P<0.05) after the low dose (11.7±0.8), but not the high dose (10.8±1.0), compared to the placebo (10.5±1.0). Pmax (in W/kg) also tended to be higher (P=0.11) in the low (3.9±0.5) compared to the placebo (3.7±0.5) or high (3.7±0.5) trials. Five out of six subjects achieved a higher Vmax and Pmax after the low vs. the high dose. We conclude that dietary nitrate has differential effects on muscle function and blood pressure in older individuals. A high dose of nitrate intake further lowers blood pressure but does not enhance muscle contractility as much as a lower dose. Supported by Indiana University Purdue University Indianapolis and by the NIA (R21 AG053606) Oxford University Press 2019-11-08 /pmc/articles/PMC6844768/ http://dx.doi.org/10.1093/geroni/igz038.320 Text en © The Author(s) 2019. Published by Oxford University Press on behalf of The Gerontological Society of America. http://creativecommons.org/licenses/by/4.0/ This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted reuse, distribution, and reproduction in any medium, provided the original work is properly cited.
spellingShingle Session 820 (Poster)
Coggan, Andrew R
Gallardo, Edgar
Gray, Derrick A
Hoffman, Richard
Moorthi, Ranjani
DIFFERENTIAL EFFECTS OF VARYING DOSES OF DIETARY NITRATE ON MUSCLE FUNCTION AND BLOOD PRESSURE IN OLDER SUBJECTS
title DIFFERENTIAL EFFECTS OF VARYING DOSES OF DIETARY NITRATE ON MUSCLE FUNCTION AND BLOOD PRESSURE IN OLDER SUBJECTS
title_full DIFFERENTIAL EFFECTS OF VARYING DOSES OF DIETARY NITRATE ON MUSCLE FUNCTION AND BLOOD PRESSURE IN OLDER SUBJECTS
title_fullStr DIFFERENTIAL EFFECTS OF VARYING DOSES OF DIETARY NITRATE ON MUSCLE FUNCTION AND BLOOD PRESSURE IN OLDER SUBJECTS
title_full_unstemmed DIFFERENTIAL EFFECTS OF VARYING DOSES OF DIETARY NITRATE ON MUSCLE FUNCTION AND BLOOD PRESSURE IN OLDER SUBJECTS
title_short DIFFERENTIAL EFFECTS OF VARYING DOSES OF DIETARY NITRATE ON MUSCLE FUNCTION AND BLOOD PRESSURE IN OLDER SUBJECTS
title_sort differential effects of varying doses of dietary nitrate on muscle function and blood pressure in older subjects
topic Session 820 (Poster)
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6844768/
http://dx.doi.org/10.1093/geroni/igz038.320
work_keys_str_mv AT cogganandrewr differentialeffectsofvaryingdosesofdietarynitrateonmusclefunctionandbloodpressureinoldersubjects
AT gallardoedgar differentialeffectsofvaryingdosesofdietarynitrateonmusclefunctionandbloodpressureinoldersubjects
AT grayderricka differentialeffectsofvaryingdosesofdietarynitrateonmusclefunctionandbloodpressureinoldersubjects
AT hoffmanrichard differentialeffectsofvaryingdosesofdietarynitrateonmusclefunctionandbloodpressureinoldersubjects
AT moorthiranjani differentialeffectsofvaryingdosesofdietarynitrateonmusclefunctionandbloodpressureinoldersubjects