A pilot study on the DNA-protective, cytotoxic, and apoptosis-inducing properties of olive-leaf extracts

Department of Genetics, University of Córdoba, Campus Rabanales, 14071 Córdoba, Spain.
Mutation Research/Fundamental and Molecular Mechanisms of Mutagenesis (Impact Factor: 3.68). 05/2011; 723(2):165-70. DOI: 10.1016/j.mrgentox.2011.05.005
Source: PubMed


Leaves of olive trees are an abundant raw material in the Mediterranean basin. They contain large amounts of potentially useful phytochemicals and could play beneficial roles in health care. In the present study, the principal bioactive phenols in olive-leaf extracts (OLEs) have been identified and quantified, and their genotoxic/antigenotoxic, cytotoxic and apoptotic effects have been assessed. The Somatic Mutation and Recombination Test (SMART) in wing imaginal discs of Drosophila melanogaster has been performed to test the possible genotoxicity of overall OLE and the individual components oleuropein and luteolin at different concentrations. The same assay was able to detect antigenotoxic activity against hydrogen peroxide as oxidative genotoxicant. None of the extracts/phenols tested showed significant mutagenic activity. This fact, together with the antigenotoxic activity against H(2)O(2) detected for all these extracts/phenols, confirmed the safety of OLE, oleuropein and luteolin in terms of DNA protection. HL60 human promyelocytic leukemia cells were used to assess the cytotoxic effects of the extracts/phenols. OLE, oleuropein and luteolin showed a dose-dependent cytotoxic effect with different IC50 (10μl/ml, 170μM, and 40μM, respectively). DNA fragmentation patterns and cell staining with acridine orange and ethidium bromide indicated that the mechanism for the cytotoxic effect of OLE, oleuropein and luteolin was the apoptotic pathway, with DNA laddering and cytoplasmic and nuclear changes. These results could help explain the mechanism of action that underlies the beneficial effect of OLE, proposed as a nutraceutical in the prevention of human cancer.

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Available from: Sebastián Ezequiel Demyda-Peyrás, May 14, 2014
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    • "in milk fat quality compared to diets based on conventional forages (Molina-Alcaide and Yanez-Ruiz, 2008). Therefore, olive leaves could be considered as an important raw-material that have the potential to be used as a natural antioxidant and as an ingredient for the stabilization of vegetable oil (Keceli and Harp, 2014) and animal feed (Molina-Alcaide and Yanez-Ruiz, 2008; Botsoglou et al., 2014; Paiva-Martins et al., 2014), but it is important to mention that they could also be used to improve human health (Anter et al., 2011). "
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    Industrial Crops and Products 09/2015; 71. DOI:10.1016/j.indcrop.2015.03.054
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    • "None of the extracts or phenols tested showed significant mutagenic activity. This fact, together with the antigenotoxic activity against H 2 O 2 , detected for total extract or its constituents , confirmed the safety of olive leaf, oleuropein, and luteolin in terms of DNA protection [32]. The protective effects of olive leaf extract on genotoxicity and oxidative damage in cultured human blood cells treated with permethrin (a highly toxic synthetic pyrethroid pesticide) were found recently [33]. "
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