Effect of olive oils on biomarkers of oxidative DNA stress in Northern and Southern Europeans

Abstract

High consumption of olive oil in the Mediterranean diet has been suggested to protect DNA against oxidative damage and to reduce cancer incidence. We investigated the impact of the phenolic compounds in olive oil, and the oil proper, on DNA and RNA oxidation in North, Central, and South European populations. In a multicenter, double-blind, randomized, controlled crossover intervention trial, the effect of olive oil phenolic content on urinary oxidation products of guanine (8-oxo-guanine, 8-oxo-guanosine and 8-oxo-deoxyguanosine) was investigated. Twenty-five milliliters of three olive oils with low, medium, and high phenolic content were administered to healthy males (n=182) daily for 3 wk. At study baseline the urinary excretion of 8-oxo-guanosine (RNA oxidation) and 8-oxo-deoxyguanosine (DNA oxidation) was higher in the Northern regions of Europe compared with Central and Southern European regions (P=0.035). Urinary excretion of the 8 hydroxylated forms of guanine, guanosine, deoxyguanosine and their nonoxidized forms were not different when comparing olive oils with low, medium, and high phenolic content given for 2 wk. Testing the effect of oil from urinary 8-oxo-deoxyguanosine changes from baseline to post-treatment showed a reduction of DNA oxidation by 13% (P=0.008). These findings support the idea that ingestion of olive oil is beneficial and can reduce the rate of oxidation of DNA. This effect is not due to the phenolic content in the olive oil. The higher DNA and RNA oxidation in Northern European regions compared with that in Central and Southern regions supports the contention that olive oil consumption may explain some of the North-South differences in cancer incidences in Europe.

The Protective Effect of the Mediterranean Diet: Focus on Cancer and Cardiovascular Risk

“…A multicenter, double-blind, randomized, crossover controlled intervention trial in Southern, Central, and Northern European countries showed a reduction in DNA oxidation of 13% (p = 0.008) for all types of olive oil consumed, although no association was found with the level of phenolics. How far these results translate into a reduced risk of breast cancer or any other cancer is uncertain and warrants further study [40] .…”

Mononuclear Cell Transcriptome Response after Sustained Virgin Olive Oil Consumption in Humans: An Exploratory Nutrigenomics Study

“…The ingestion of VOO can reduce the rate of oxidation of DNA (Machowetz et al, 2007). Its phenolic content has been shown to modulate the oxidative/antioxidative status of healthy men who consumed a very low-antioxidant diet (Weinbrenner et al, 2004).…”

“…Only recently has VOO been acknowledged as being more than a monounsaturated fat, because its phenolic content provides benefits for plasma lipid concentrations and oxidative damage Machowetz et al, 2007). It is believed that the health benefits derived from the consumption of VOO (Estruch et al, 2006;Machowetz et al, 2007) are due to the interaction of its nutrients and minor components with genes, thus influencing their expression (i.e., nutritional transcriptomics).…”

“…It is believed that the health benefits derived from the consumption of VOO (Estruch et al, 2006;Machowetz et al, 2007) are due to the interaction of its nutrients and minor components with genes, thus influencing their expression (i.e., nutritional transcriptomics). Some of the gene expression-mediated mechanisms underlying the beneficial health effects of particular components of olive oil in humans have been already examined in vitro and in animal models.…”

Does Olive Oil Attenuate Ciprofloxacin-Induced Renal Cortical Toxicity? Light and Electron Microscopic Study

“…It could be used as a prophylactic mean for gastric ulcer or cancer [15] . In addition, it aids in cancer prevention via reduction of oxidative damage to DNA and RNA [16] and helps the nerves to act properly and increases serotonin [17] . Besides, the oleuropein content of olive oil can block low density lipoprotein oxidation [18] .…”