Variability in nitrate-reducing oral bacteria and nitric oxide metabolites in biological fluids following dietary nitrate administration: An assessment of the critical difference

Publication date: Available online 5 December 2018Source: Nitric OxideAuthor(s): Luke Liddle, Mia C. Burleigh, Chris Monaghan, David J. Muggeridge, Nicholas Sculthorpe, Charles R. Pedlar, John Butcher, Fiona L. Henriquez, Chris EastonAbstractThere is conflicting evidence on whether dietary nitrate supplementation can improve exercise performance. This may arise from the complex nature of nitric oxide (NO) metabolism which causes substantial inter-individual variability, within-person biological variation (CVB), and analytical imprecision (CVA) in experimental endpoints. However, no study has quantified the CVA and CVB of NO metabolites or the factors that influence their production. These data are important to calculate the critical difference (CD), defined as the smallest difference between sequential measurements required to signify a true change. The main aim of the study was to evaluate the CVB, CVA, and CD for markers of NO availability (nitrate and nitrite) in plasma and saliva before and after the ingestion of nitrate-rich beetroot juice (BR). We also assessed the CVB of nitrate-reducing bacteria from the dorsal surface of the tongue. It was hypothesised that there would be substantial CVB in markers of NO availability and the abundance of nitrate-reducing bacteria. Ten healthy male participants (age 25 ± 5 years) completed three identical trials at least 6 days apart. Blood and saliva were collected before and after (2, 2.5 and 3 h) ingestion of 140 ml of BR ...
Source: Nitric Oxide - Category: Chemistry Source Type: research