Atividade antioxidante, antigenotóxica e antimutagênica de extratos de folhas de vitis labrusca (variedade Isabel) orgânica e convencional em células de mamífero v79

Abstract

The grape production plays an important role in world’s economy and history. Currently, vineyards can be found in organic management, which use of pesticides, fertilizers and genetic engineering resources are prohibited, and conventional vineyards, which can be treated with different chemicals. On each harvest is produced a large amount of vine leaves, which are mainly disposed in the environment or in some countries, used in folk medicine and as food and beverage. Therefore, the objective of this study was to evaluate the antioxidant antigenotoxic and antimutagenic activities of aqueous extracts of Vitis labrusca leaves cv. Isabella variety. The polyphenols and ascorbic acid content and the major compounds were determined. The cell line V79 was treated for 3 hours with the leaves extracts and then exposed for one hour to the oxidiative agent hydrogen peroxide or MMS mutagen. After that, the cell viability was analysed by MTT reduction and clonogenic survival assays, the lipid peroxidation level and protein carbonyl formation were also observed. The antigenotoxic effect of the extracts was analyzed by the alkaline comet assay and using enzyme endonuclease III (ENDO III) and phosphatidyl pyrimidine DNA glycosylase (FPG), enzymes that recognize damage to purines and pyrimidines. The antimutagenic activity of the extracts was evaluated by micronucleus assay, using MMS, a known mutagenic compound. For the determination of in vitro antioxidant activity the scavenging activity of the DPPH● was verified, and the ability of extracts to mimic the enzymes SOD and CAT. The organic extract present highest polyphenol, ascorbic acid content and also quercetin-3-glucoside and rutin. However, treatment with organic and conventional extract prevented cell death, lipid peroxidation and protein carbonyl the same manner. Moreover, the organic extract showed a better antimutagenic and antigenotoxic activity than conventional extract. Although it was observed that both extracts have in vitro antioxidant activity, and the organic extract showed better ability to scavenging DPPH●, and greater SOD and CAT-like activity than the conventional. It is possible that the polyphenols and ascorbic acid present in extracts are responsible for the results found in this work. Although other studies are necessary, the data obtained in this work shows that the aqueous extracts of grapevines leaves, cv. Isabella, both organic and conventional management, have important antigenotoxic, antimutagenic and antioxidant activity and can minimize the damage associated with different pathologies.