Bryan Heath Curry1, Vernon Bond2, Sudhakar Pemminati3, Vasavi Rakesh Gorantla4, Yulia Andreevna Volkova5, Kishan Kadur6, Richard Mark Millis7. 1. Professor, Department of Medicine, Division of Cardiology, Howard University College of Medicine and Howard University Hospital , Washington, DC 20060, United States of America . 2. Professor, Department of Recreation, Human Performance and Leisure Studies and Exercise Science and Human Nutrition Laboratory, Howard University Cancer Centre , Washington, DC 20060, United States of America . 3. Associate Professor, Department of Medical Pharmacology, AUA College of Medicine and Manipal University , Antigua . 4. Assistant Professor, Department of Behavioural Sciences and Neuroscience, AUA College of Medicine , Antigua . 5. Instructor, Department of Clinical Medicine, AUA College of Medicine , Antigua . 6. Assistant Professor, Department of Medical Physiology, AUA College of Medicine , Antigua . 7. Professor, Department of Medical Physiology, AUA College of Medicine , Antigua .
Abstract
INTRODUCTION: Beetroot Juice (BJ) contains dietary nitrates that increase the blood Nitric Oxide (NO) level, decrease Blood Pressure (BP), increase athletic performance and improve cognitive functions but the mechanism remains unclear. Ultrasonographic measurement of middle cerebral artery blood flow velocity with computation of Cerebral Augmentation Index (CAIx) is a measure of the reflected flow signal, modulated by changes in cerebrovascular resistance and compliance. AIM: This pilot study tests the hypothesis that ingestion of an amount of BJ sufficient to raise the blood NO level two-to three-fold, decreases Transcranial Doppler (TCD) measured CAIx. MATERIALS AND METHODS: Ten healthy young-adult African-American women were studied at two levels of submaximal exercise, 40% and 80% of their predetermined peak oxygen consumptions. The subjects ingested nitrate-free orange juice (OJ, control) and an isocaloric BJ beverage (1.5 mg/mL nitrate, 220 Cal), on different days, 1-2 weeks apart. RESULTS: The BJ treatment increased blood NO and decreased systolic BP at rest and at the two levels of exercise. The BJ treatment decreased CAIx only at the two levels of exercise (from 79 ± 2% to 62 ± 2% and from 80 ± 2% to 60 ± 3%, p<0.05). Exercise increased TCD-measured resistance and pulsatility indices (RIx, PIx) without changing AIx. The BJ treatment had no effect on RIx and PIx. CONCLUSION: These findings suggest that decreased CAIx associated with aerobic exercise reflects the change in cerebral haemodynamics resulting from dietary nitrate supplementation. Future studies should determine whether the BJ-induced decrement in CAIx is correlated with an improvement in brain function.
INTRODUCTION: Beetroot Juice (BJ) contains dietary nitrates that increase the blood Nitric Oxide (NO) level, decrease Blood Pressure (BP), increase athletic performance and improve cognitive functions but the mechanism remains unclear. Ultrasonographic measurement of middle cerebral artery blood flow velocity with computation of Cerebral Augmentation Index (CAIx) is a measure of the reflected flow signal, modulated by changes in cerebrovascular resistance and compliance. AIM: This pilot study tests the hypothesis that ingestion of an amount of BJ sufficient to raise the blood NO level two-to three-fold, decreases Transcranial Doppler (TCD) measured CAIx. MATERIALS AND METHODS: Ten healthy young-adult African-American women were studied at two levels of submaximal exercise, 40% and 80% of their predetermined peak oxygen consumptions. The subjects ingested nitrate-free orange juice (OJ, control) and an isocaloric BJ beverage (1.5 mg/mL nitrate, 220 Cal), on different days, 1-2 weeks apart. RESULTS: The BJ treatment increased blood NO and decreased systolic BP at rest and at the two levels of exercise. The BJ treatment decreased CAIx only at the two levels of exercise (from 79 ± 2% to 62 ± 2% and from 80 ± 2% to 60 ± 3%, p<0.05). Exercise increased TCD-measured resistance and pulsatility indices (RIx, PIx) without changing AIx. The BJ treatment had no effect on RIx and PIx. CONCLUSION: These findings suggest that decreased CAIx associated with aerobic exercise reflects the change in cerebral haemodynamics resulting from dietary nitrate supplementation. Future studies should determine whether the BJ-induced decrement in CAIx is correlated with an improvement in brain function.
Authors: Katherine E Lansley; Paul G Winyard; Jonathan Fulford; Anni Vanhatalo; Stephen J Bailey; Jamie R Blackwell; Fred J DiMenna; Mark Gilchrist; Nigel Benjamin; Andrew M Jones Journal: J Appl Physiol (1985) Date: 2010-11-11
Authors: Vernon Bond; Bryan H Curry; Richard G Adams; M Sadegh Asadi; Richard M Millis; Georges E Haddad Journal: Cardiol Res Pract Date: 2013-12-25 Impact factor: 1.866
Authors: Vernon Bond; Bryan H Curry; R George Adams; M Sadegh Asadi; Kimani A Stancil; Richard M Millis; Georges E Haddad Journal: ISRN Physiol Date: 2014-02-23
Authors: Gadah Albasher; Tarfa Albrahim; Nouf Alsultan; Saleh Alfaraj; Mada S Alharthi; Rami B Kassab; Ahmed E Abdel Moneim Journal: Environ Sci Pollut Res Int Date: 2019-12-10 Impact factor: 4.223