The Effect Of 7 Consecutive Days Of Piceatannol Ingestion On Endothelial Function Following Endurance Exercise

Piceatannol within a passienol tablet has been known to promote nitric oxide (NO) bioavailability, leading to vasodilation (Sano et al. 2011). However, the influence of passienol ingestion for a week on endothelial function at rest, during and after exercise has not been fully elucidated. PURPOSE: The purpose of the present study was to determine the effect of 7 consecutive days of piceatannol ingestion on endothelial function at rest, during and after low-intensity endurance exercise in young healthy subjects. METHODS: Eight physically active male subjects (age; 21 ± 1 years, height; 171.1 ± 6.5 cm, body weight; 65.1 ± 8.9 kg, BMI; 22.2 ± 2.0 kg/m2) performed two exercise trials. The participants ingested either 10 mg of piceatannol (PIC trial) or placebo tablet (CON trial) for each 7 consecutive days before the experimental day. This study was conducted using a randomized, a double-blind and crossover design. The exercise was 60 min of cycling exercise at 30% of VO2max. Brachial artery flow-mediated dilation (FMD) was measured using duplex Doppler ultrasound in the supine position before, 10, 30 and 60 min after the exercise. Brachial artery blood flow, diameter and blood velocity were evaluated at same time points as FMD. Moreover, heart rate (HR), blood pressure and RPE were measured at before exercise, and 15, 30, 45 and 60 min during exercise. RESULTS: Average HR throughout the exercise was significantly higher in the PIC trial (89 ± 14 bpm) than in the CON trial (85 ± 11 bpm, P < 0.05). However, there was no significant difference between trials for average RPE (PIC trial: 9.8 ± 2.1, CON trial: 9.6 ± 1.9, P = 0.58). Brachial artery blood flow responses did not differ significantly in both trials. There were no significant differences in brachial artery FMD at rest and after the exercise (at rest: 7.7 ± 4.2% in the CON trial vs. 8.6 ± 5.5% in the PIC trial, 10 min of after the exercise: 7.8 ± 3.9% in the CON trial vs. 7.1 ± 2.9% in the PIC trial). CONCLUSIONS: Seven consecutive days of piceatannol ingestion did not result in improvement of endothelial function at rest during and after low-intensity endurance exercise.