Aging, Nitrate, Endothelial Function and Muscle Oxygenation

Effect of a Beetroot-based Nutritional Gel on Vascular Function and Forearm Muscle Oxygenation Responses in the Elderly at Cardiometabolic Risk

Aging has been associated with reduced bioavailability of nitric oxide (NO) and endothelial dysfunction. Beetroot consumption, a nitrate-rich food, has been associated with increased NO bioconversion, which may promote beneficial effects on vascular health. The present study evaluated the effects of a beetroot-based nutritional gel (BG) on vascular function, arterial stiffness and blood pressure in the elderly at cardiometabolic risk. Twenty elderly individuals were submitted to BG and nitrate-depleted gel (PLA) interventions. Brachial flow-mediated dilation (FMD), blood flow velocity (BFV), peak wave velocity (PWVβ), augmentation index (AI), stiffness parameter (β), pressure-strain elasticity modulus (Ep), arterial compliance (AC), muscle oxygenation and function were measured 90 min after interventions. Urinary nitrate, nitrite, systolic blood pressure (SBP), diastolic blood pressure (DBP) and heart rate (HR) were measured at baseline, 90 min and 150 min after interventions.

Inclusion Criteria:

• Elderly participants (≥ 65 years)
• Taking between 1 and 3 anti-hypertensive medications for high blood pressure;
• Elevated triglycerides ≥ 150 mg/dL;
• Reduced HDL-cholesterol < 50 mg/dL for women and < 40 mg/dL for men;
• Elevated waist circumference by population definition (male: > 102 cm and female: > 88 cm).

Exclusion Criteria: elevated fasting glucose (≥ 100 mg/dL), smoking, beetroot allergy, unwillingness to avoid beetroot products during the entire study, other chronic diseases (diabetes, liver disease, etc.), or acutely ill.