Coffee modulates transcription factor Nrf2 and highly increases the activity of antioxidant enzymes in rats.

This study investigated the effect of a 28 day administration of coffee brew on the activity of antioxidant enzymes in rats. After this period of 2.0 mL/day dosages of this beverage, the activities of hepatic superoxide dismutase, catalase, and glutathione peroxidase increased 74.8, 59.4, and 135.2%, respectively, whereas the cytosolic level of Nrf2 increased 131.3%. At the same time, the total antioxidant capacity of the hepatic tissue increased 25.1%, improving the defensive status against oxidative stress. At the end of the experiment, the levels of biomarkers alanine transaminase and aspartate transaminase remained equal to the control group, and no changes were observed in the hepatic histoarchiteture of the animals, suggesting that the liver tissue was not impaired by the exposure to coffee. The changes in enzyme activities and antioxidant capacity were statistically significant (p < 0.05), indicating that coffee could be considered an important alternative against oxidative stress and its correlated degenerative diseases.