1. Altered Oral Nitrate Reduction and Bacterial Profiles in Hypertensive Women Predict Blood Pressure Lowering Following Acute Dietary Nitrate Supplementation.
- Author
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Willmott T, Ormesher L, McBain AJ, Humphreys GJ, Myers JE, Singh G, Lundberg JO, Weitzberg E, Nihlen C, and Cottrell EC
- Subjects
- Adult, Humans, Female, Pregnancy, Nitrates, Blood Pressure, Nitrites, RNA, Ribosomal, 16S, Bacteria, Dietary Supplements, Hypertension diagnosis, Hypertension drug therapy, Beta vulgaris
- Abstract
Background: The efficacy of dietary nitrate supplementation to lower blood pressure (BP) in pregnant women is highly variable. We aimed to investigate whether differences in oral microbiota profiles and oral nitrate-reducing capacity may explain interindividual differences in BP lowering following nitrate supplementation., Methods: Participants recruited for this study were both pregnant and nonpregnant women, with or without hypertension (n=55). Following an overnight fast, plasma, saliva, and tongue scraping samples were collected for measurement of nitrate/nitrite concentrations, oral NaR (nitrate reductase) activity, and microbiota profiling using 16S rRNA gene sequencing. Baseline BP was measured, followed by the administration of a single dose of dietary nitrate (400 mg nitrate in 70 mL beetroot juice). Post-nitrate intervention, plasma and salivary nitrate/nitrite concentrations and BP were determined 2.5 hours later., Results: Women with hypertension had significantly lower salivary nitrite concentrations ( P =0.006) and reduced abundance of the nitrate-reducing taxa Veillonella ( P =0.007) compared with normotensive women. Oral NaR activity was not significantly different in pregnant versus nonpregnant women ( P =0.991) but tended to be lower in hypertensive compared with normotensive women ( P =0.099). Oral NaR activity was associated with both baseline diastolic BP ( P =0.050) and change in diastolic BP following acute nitrate intake ( P =0.01, adjusted for baseline BP)., Conclusions: The abundance and activity of oral nitrate-reducing bacteria impact both baseline BP as well as the ability of dietary nitrate supplementation to lower BP. Strategies to increase oral nitrate-reducing capacity could lower BP and enhance the efficacy of dietary nitrate supplementation, in pregnancy as well as in nonpregnant adults., Registration: URL: https://www., Clinicaltrials: gov; Unique identifier: NCT03930693., Competing Interests: Disclosures J.O. Lundberg and E. Weitzberg are coinventors on patent applications filed in 2007 for the use of inorganic nitrate and nitrite as therapeutics. The other authors report no conflicts.
- Published
- 2023
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