RESUMO
The purpose of this study was to examine whether the supplementation with an açai (Euterpe oleracea Mart.) seed extract (ASE) would affect the aerobic exercise performance in rats and correlate with the vascular function, muscle oxidative stress and mitochondrial biogenesis. Male Wistar rats were divided into five groups: Sedentary, Sedentary with chronic supplementation of ASE, Training, Training with chronic (200 mg/Kg/day intragastric gavage for 5 weeks) or acute (30 min before the maximal treadmill stress test (MST) supplementation with ASE. The exercise training was performed on a treadmill (30 min/day; 5 days/week) for 4 weeks. The chronic supplementation with ASE increased the exercise time (58%) and the running distance (129%) in relation to the MST, while the Training group increased 40% and 78% and the Training with acute ASE group increased 30% and 63%, respectively. The training-induced increase of ACh vasodilation was not changed by ASE, but the norepinephrine-induced vasoconstriction was reduced by chronic and acute supplementation with ASE. The increased levels of malondialdehyde in soleus muscle homogenates from the Training group was reduced only by chronic supplementation with ASE. The muscle antioxidant defense, NO2 levels, and expression of the mitochondrial biogenesis-related proteins (PGC1α, SIRT-1, p-AMPK/AMPK, Nrf-2) were not different between Training and Sedentary groups, but all these parameters were increased in the Training with Chronic ASE compared with the Sedentary groups. In conclusion, chronic supplementation with ASE improves aerobic physical performance by increasing the vascular function, reducing the oxidative stress, and up-regulating the mitochondrial biogenesis key proteins.