Caracterização das propriedades antioxidantes, hipoglicemiantes e neuroprotetoras da erva mate em diferentes modelos

Abstract

Yerba mate is the product of the processing of dried and ground leaves of a tree species, known as Ilex paraguariensis. The commercial presentation of yerba mate is used in the preparation of a traditional drink, widely consumed in South America. Data from the literature has proven a variety of beneficial effects of yerba mate, especially the antioxidant. It is known that a great number of pathologies present oxidative stress as one of its harmful mechanisms, in this way, the search for natural compounds that can balance such situations has intensified in recent years. Considering the mentioned aspects, the main objective of the present study was evaluate the possible protective effects of Ilex paraguariensis extract in different perspectives with emphasis on oxidative stress. Initially, was made the characterization of HPLC extract, followed by an in vitro comparison in synaptosomes, of the extract (200 mg / mL) with its major compound, chlorogenic acid CGA (2 mg / mL) in ROS formation, lipid peroxidation, mitochondrial function by MTT and the GSH / GSSG ratio. Therefore, in vivo evaluation was performed, where male Wistar rats (300-330 g) underwent movement restriction stress associated with other stress stimuli for 21 days, 6 hours per day (chronic) and treated with extract (200 mg / mL) or CGA (2 mg / mL) and behavioral parameters of locomotor activity and anxiety were analyzed, as well as aspects of cellular damage in the cortex, hippocampus and striatum. Finally, in a model of diabetic mice, induced with streptozotocin (100 mg / kg), were verified the effects of yerba mate extract (850 mg / kg) on glucose levels, diabetic neuropathy and markers Of oxidative stress, in kidney, liver and brain. The yerba mate extract was shown to be more effective than chlorogenic acid in the protection of oxidative damage in synaptosomes, by reducing ROS formation, lipid peroxidation and glutathione depletion, which may explain the effect of the extract in preventing mitochondrial dysfunction evaluated. Likewise, in the model of stress by restriction of movement, the extract of mate grass was more effective than the chlorogenic acid in preventing the behavioral alterations of the animals. The group that received extract as treatment had locomotor activity equal to or greater than the control group. The animals treated with extracts were also less anxious than those of the stressed group that did not receive treatment. In addition, the extract exhibited a protective effect on cell damage in cortex, hippocampal and striatum, as treated animals had a higher number of viable cells in these tissues. Regarding the effects of the extract in the induced model of diabetes, it was verified that the yerba mate has activity of protection to the oxidative stress involved in the pathogenesis of this pathology, in addition to significantly reduce the glycemic level of the animals and present protective effect to diabetic neuropathy. Based on the results found, it is possible to say that, in general, yerba mate acts in the protection of different aspects of oxidative stress due to the synergism of its components, considering that the isolated chlorogenic acid did not present a protective effect equal or greater than of the extract. Through its antioxidant effect, present benefits in reducing the damage caused by chronic hyperglycemia in diabetes mellitus, in the modulation of neuroprotective effects and mitochondrial function.