Caffeinated instant coffee prevents an increase in exercise-mediated superoxide anion production in rat peritoneal neutrophils

The present study analyzed the in vivo effects of drinking caffeinated and decaffeinated instant coffee (8% w/v) by adult male Wistar rats submitted to high-intensity exercises. The parameters used in the evaluation were the determination of the activities of NADPH oxidase, myeloperoxidase and other antioxidant enzymes present in neutrophils of rats. It was observed that exercise-induced superoxide anion production depends on the NADPH oxidase activity (estimated by the cytochrome C reduction test) in peritoneal neutrophils (p < 0.05). The intake of caffeinated and decaffeinated instant coffee beverages and of a caffeine solution to 1.67% did not induced changes in the activities of the enzymes myeloperoxidase, superoxide dismutase and glutathione peroxidase (p < 0.05). But consumption of caffeinated instant coffee drink prevented an increase in NADPH oxidase-mediated superoxide production induced by highly intense exercise in rat neutrophils. While the decaffeinated instant coffee drink or caffeine solution alone did not affect NADPH oxidase-mediated superoxide production. We suggest that this activity is associated with the chemical composition and concentration of phenolic compounds and other antioxidant substances formed during roasting. From the obtained results, it was concluded that moderate intake of caffeinated instant coffee (equivalent to a daily human consumption of 4 50-mLcups of coffee) may have beneficial effects on health, contributing to a reduction in superoxide anion generation. Therefore, more research must be conducted to elucidate the mechanism of action of caffeinated coffee on NADPH oxidase in neutrophils.

Effects of the consumption of caffeinated and decaffeinated instant coffee beverages on oxidative stress induced by strenuous exercise in rats.

Many authors attribute the antioxidant activity of brewed coffee to its caffeine content. In addition, caffeine intake has been associated with increased performance during physical exercise. This study analyzed the in vivo effects of drinking caffeinated and decaffeinated instant coffee (8%, w/v) on oxidative stress and antioxidant enzyme activity in the anterior tibialis muscles of rats subjected to intense exercise. It was observed that exercise induced lipid peroxidation (estimated using malondialdehyde) and protein oxidation (evaluated by determining the formation of carbonyl groups) in the muscle (P < 0.05). Decaffeinated instant coffee and caffeine solution did not exhibit antioxidant activity in vivo. Caffeinated instant coffee beverage intake did not induce changes in superoxide dismutase and glutathione peroxidase activities but was able to diminish lipid and protein oxidation in the anterior tibialis muscles of rats after exercise (P < 0.05), contributing to a reduction in the oxidative stress triggered by exercise.