Efeito promnésico e antioxidante do café no sistema nervoso central de ratos

Abstract

Coffee is a very popular beverage, consumed worldwide and its effect on health protection is well studied. The goal of the present study was to investigate the effect of coffee, as a functional food, on the cerebral antioxidant system and cognitive processes in rats. The activities of antioxidant enzymes glutathione reductase (GR), glutathione peroxidase and superoxide dismutase (SOD), glutathione S-transferase (GST), as well lipid peroxidation and reduced glutathione content were determined.The paradigms of open field and object recognition were used to assess the locomotor and exploratory activity and learning and memory, respectively. Finally, we analyzed the levels of Aß-amyloid protein (1-40) in the cortex and hippocampus of control and streptozotocin-induced diabetes rats after coffee and caffeine consumption. Five groups of male rats were used: control group (GC), fed ad libitum; coffee group 3%(G3%), fed as GC but with the diet containing coffee extract (3%); coffee group 6% (G6%), fed as GC but with the diet containing coffee extract (6%); caffeine group 0,04% (G0,04%), fed with control diet supplemented with 0,04% of caffeine and caffeine group 0,08% (G0,08%), fed with control diet supplemented with 0,08% of caffeine. The results indicated that the intake of coffee or caffeine reduced the lipid peroxidation of brain membranes, increased the concentration of reduced glutathioneand the activities of the antioxidant enzymes, GR, SOD and GST. In addition, longterm memory tested on object recognition test was improved, but it was not accompanied by an increase in locomotor and exploratory activity of the animals. The consumption of coffee or caffeine in the diet has not been able to reduce the levels of Aß-amyloid increased by STZ in the cortex and hippocampus of the rats. The data obtained indicate that coffee has promnesic and cerebral antioxidant effects,therefore, it can be considered as a functional food.Key words: coffee, caffeine, endogenous antioxidant system, learning and memory, Aß-amyloid protein.