Heart Histopathology and Mitochondrial Ultrastructure in Aged Rats Fed for 24 Months on Different Unsaturated Fats (Virgin Olive Oil, Sunflower Oil or Fish Oil) and Affected by Different Longevity.

Diet plays a decisive role in heart physiology, with lipids having especial importance in pathology prevention and development. This study aimed to investigate how dietary lipids varying in lipid profile (virgin olive oil, sunflower oil or fish oil) affected the heart of rats during aging. Heart histopathology, mitochondrial morphometry, and oxidative status were assessed. Typical histopathological features associated with aging, such as valvular lesions, endomyocardical hyperplasia, or papillary muscle calcification, were found at a low extent in all the experimental groups. The most relevant finding was that inflammation registered by fish oil group was lower compared to the other treatments. At the ultrastructural level, heart mitochondrial area, perimeter, and aspect ratio were higher in fish oil-fed rats than in those fed on sunflower oil. Concerning oxidative stress markers, there were differences only in coenzyme Q levels and catalase activity, lower in sunflower oil-fed animals compared with those fed on fish oil. In summary, dietary intake for a long period on dietary fats with different fatty acids profile led to differences in some aspects associated with the aging process at the heart. Fish oil seems to be the fat most protective of heart during aging.

Chemical Profile and Safety Assessment of a Food-Grade Acetogenin-Enriched Antimicrobial Extract from Avocado Seed.

Acetogenins are bioactive fatty acid derivatives found in avocado tissues. Their efficacy as antimicrobials has been documented and initiated interest to use them as replacements of synthetic food additives. The present work focused on evaluation of multiple analytical methodologies for detection and quantification of organic solids present in a food-grade acetogenin-enriched extract (Avosafe®), and on its safety evaluations using bacterial reverse mutation (AMES) tests and acute oral toxicity to rat assays. Results confirmed chemical structures of two acetogenins as present in Avosafe® (AcO-avocadyne-(0) and AcO-avocadiene B-(3)), and together with seven other previously known compounds, quantified 94.74 ± 5.77% w/w of its solids as acetogenins. Safety evaluations indicated that Avosafe® was non-mutagenic and had an acute median lethal oral dose (LD50) to rats higher than the maximum concentration tested (>2000 mg·kg-1), with no signs of macroscopic abnormalities in organs. Mean body weight and hematological and biochemical parameters were normal after 14 days of a single oral dose of 2000 mg·kg-1. The results advance scientific information on the safety of avocado seed acetogenins and also generate new knowledge on profiles and concentrations of individual acetogenins found in avocado tissues (seed, pulp, and leaves) and in Avosafe®.

Gene pathways associated with mitochondrial function, oxidative stress and telomere length are differentially expressed in the liver of rats fed lifelong on virgin olive, sunflower or fish oils.

This study investigates the effect of lifelong intake of different fat sources rich in monounsaturated (virgin olive oil), n6 polyunsaturated (sunflower oil) or n3 polyunsaturated (fish oil) fatty acids in the aged liver. Male Wistar rats fed lifelong on diets differing in the fat source were killed at 6 and at 24 months of age. Liver histopathology, mitochondrial ultrastructure, biogenesis, oxidative stress, mitochondrial electron transport chain, relative telomere length and gene expression profiles were studied. Aging led to lipid accumulation in the liver. Virgin olive oil led to the lowest oxidation and ultrastructural alterations. Sunflower oil induced fibrosis, ultrastructural alterations and high oxidation. Fish oil intensified oxidation associated with age, lowered electron transport chain activity and enhanced the relative telomere length. Gene expression changes associated with age in animals fed virgin olive oil and fish oil were related mostly to mitochondrial function and oxidative stress pathways, followed by cell cycle and telomere length control. Sunflower oil avoided gene expression changes related to age. According to the results, virgin olive oil might be considered the dietary fat source that best preserves the liver during the aging process.

Doxorubicin-induced oxidative stress in rats is efficiently counteracted by dietary anthocyanin differently enriched strawberry (Fragaria × ananassa Duch.).

This study investigated the effects of two different strawberry cultivars, Adria and Sveva, against doxorubicin (DOX)-induced toxicity in rats. A controlled dietary intervention was conducted over 16 weeks with four groups: (i) normal diet; (ii) normal diet + DOX injection; (iii) Adria supplementation + DOX injection; and (iv) Sveva supplementation + DOX injection. Sveva presented higher total antioxidant capacity value and phenol and and vitamin C levels than Adria, which in turn presented higher anthocyanin contents. DOX drastically increased lymphocyte DNA damage, liver biomarkers of protein and lipid oxidation, and mitochondrial ROS content and markedly decreased plasma retinol level, liver antioxidant enzymes, and mitochondrial functionality. After 2 months of strawberry supplementation, rats presented a significant reduction of DNA damage and ROS concentration and a significant improvement of oxidative stress biomarkers, antioxidant enzyme activities, and mitochondrial performance. These results suggest that strawberry supplementation can counteract DOX toxicity, confirming the potential health benefit of strawberry in vivo against oxidative stress.

Diets based on virgin olive oil or fish oil but not on sunflower oil prevent age-related alveolar bone resorption by mitochondrial-related mechanisms.

BACKGROUND/OBJECTIVES: Aging enhances frequency of chronic diseases like cardiovascular diseases or periodontitis. Here we reproduced an age-dependent model of the periodontium, a fully physiological approach to periodontal conditions, to evaluate the impact of dietary fat type on gingival tissue of young (6 months old) and old (24 months old) rats. METHODS/FINDINGS: Animals were fed life-long on diets based on monounsaturated fatty acids (MUFA) as virgin olive oil, n-6 polyunsaturated fatty acids (n-6PUFA), as sunflower oil, or n-3PUFA, as fish oil. Age-related alveolar bone loss was higher in n-6PUFA fed rats, probably as a consequence of the ablation of the cell capacity to adapt to aging. Gene expression analysis suggests that MUFA or n-3PUFA allowed mitochondria to maintain an adequate turnover through induction of biogenesis, autophagy and the antioxidant systems, and avoiding mitochondrial electron transport system alterations. CONCLUSIONS: The main finding is that the enhanced alveolar bone loss associated to age may be targeted by an appropriate dietary treatment. The mechanisms involved in this phenomenon are related with an ablation of the cell capacity to adapt to aging. Thus, MUFA or n-3PUFA might allow mitochondrial maintaining turnover through biogenesis or autophagy. They might also be able to induce the corresponding antioxidant systems to counteract age-related oxidative stress, and do not inhibit mitochondrial electron transport chain. From the nutritional and clinical point of view, it is noteworthy that the potential treatments to attenuate alveolar bone loss (a feature of periodontal disease) associated to age could be similar to some of the proposed for the prevention and treatment of cardiovascular diseases, a group of pathologies recently associated with age-related periodontitis.

Squalene ameliorates atherosclerotic lesions through the reduction of CD36 scavenger receptor expression in macrophages.

SCOPE: Anti-atherogenic features of olive oil (OO) have been attributed, in part, to minor compounds, via diverse mechanisms, although its effects on the CD36 receptor have not been examined. We investigated the effects of minor compounds of OO (squalene (SQ), tyrosol (Tyr) and hydroxytyrosol (OH-Tyr)), on the expression of the CD36 receptor, as well as on monocyte/macrophage differentiation and proliferation. METHODS AND RESULTS: U937 monocytic cells and macrophages (obtained with 10 nM phorbol-myristate-acetate) were exposed to Tyr, OH-Tyr or SQ at 0, 10, 75 and 200 µM with/without native or oxidised LDL(oxLDL). Flow cytometry was used to achieve the expression of CD36 in both cell types exposed to oxLDL plus antioxidants, as well as the inhibition of monocyte/macrophage differentiation after oxLDL and apoptosis. SQ caused a dose-dependent reduction of CD36 in the presence of native and moderate LDL in monocytes and macrophages. Phenotype-dependent cytotoxic and antiproliferative effects were found for OH-Tyr (p < 0.05), while SQ affected neither monocytes nor macrophages (p < 0.01). CONCLUSION: SQ does not prevent monocyte migration and activation into macrophages, but it would inhibit oxLDL uptake by macrophages, by reducing CD36 expression. This study provides new data about the role of the components of OO in the prevention of atherosclerosis.

Age-related changes in brain mitochondrial DNA deletion and oxidative stress are differentially modulated by dietary fat type and coenzyme Q10.

Mitochondria-related oxidative damage is a primary event in aging and age-related neurodegenerative disorders. Some dietary treatments, such as antioxidant supplementation or the enrichment of mitochondrial membranes with less oxidizable fatty acids, reduce lipid peroxidation and lengthen life span in rodents. This study compares life-long feeding on monounsaturated fatty acids (MUFAs), such as virgin olive oil, and n-6 polyunsaturated fatty acids, such as sunflower oil, with or without coenzyme Q10 supplementation, with respect to age-related molecular changes in rat brain mitochondria. The MUFA diet led to diminished age-related phenotypic changes, with lipoxidation-derived protein markers being higher among the older animals, whereas protein carbonyl compounds were lower. It is noteworthy that the MUFA diet prevented the age-related increase in levels of mitochondrial DNA deletions in the brain mitochondria from aged animals. The findings of this study suggest that age-related oxidative stress is related, at the mitochondrial level, to other age-related features such as mitochondrial electron transport and mtDNA alterations, and it can be modulated by selecting an appropriate dietary fat type and/or by suitable supplementation with low levels of the antioxidant/electron carrier molecule coenzyme Q.

Hydroxytyrosol inhibits growth and cell proliferation and promotes high expression of sfrp4 in rat mammary tumours.

SCOPE: Hydroxytyrosol (a phenolic compound derived from virgin olive oil) has demonstrated an anti-tumour effect in several tumour cell lines in addition to other health-related properties. The aim of this study was to investigate, for the first time in an animal model of experimental mammary carcinoma, the anti-cancer ability of hydroxytyrosol and to discover which pathways are modified by hydroxytyrosol. METHODS AND RESULTS: Dimethylbenz[α]anthracene-induced mammary tumours were induced in 28 female Sprague-Dawley rats and ten of them were treated with hydroxytyrosol (0.5 mg/kg b.w. 5 days/week for 6 wk). cDNA microarray and quantitative RT-PCR experiments were performed. Hydroxytyrosol was found to inhibit the experimental mammary tumour growth and proliferation rate, with results comparable to those of doxorubicin but better with regard to the histopathological outcome. It also altered the expression of genes related to apoptosis, cell cycle, proliferation, differentiation, survival and transformation pathways. CONCLUSIONS: This study shows that hydroxytyrosol exerts anti-cancer effects in Sprague-Dawley rats with experimental mammary tumours, inhibiting growth and cell proliferation in mammary tumours. Moreover, hydroxytyrosol alters several genes associated with cell proliferation, apoptosis and the Wnt signalling pathway, promoting a high expression of Sfrp4. However, further studies are necessary to better understand the mechanisms of hydroxytyrosol.

Hydroxytyrosol: from laboratory investigations to future clinical trials.

Mediterranean countries have lower rates of mortality from cardiovascular disease and cancer than Northern European or other Western countries. This has been attributed, at least in part, to the so-called Mediterranean diet, which is composed of specific local foods, including olive oil. Traditionally, many beneficial properties associated with this oil have been ascribed to its high oleic acid content. Today, it is clear that many of the beneficial effects of ingesting virgin olive oil are due to its minor compounds. This review summarizes the existing knowledge concerning the chemistry, pharmacokinetics, and toxicology of hydroxytyrosol, a minor compound of virgin olive oil, as well as this compound's importance for health. The main findings in terms of its beneficial effects in cardiovascular disease and cancer, including its properties against inflammation and platelet aggregation, are emphasized. New evidence and strategies regarding the use of hydroxytyrosol as a natural drug for the prevention and treatment of diseases with high incidences in Western countries are also presented.

Gingival vascular damage in atherosclerotic rabbits: hydroxytyrosol and squalene benefits.

Cardiovascular alterations and periodontal disease have been associated, although cardiovascular disease treatments have not yet been tested against periodontal alterations. We investigated effects of squalene, hydroxytyrosol and coenzyme Q(10) on gingival tissues of rabbits fed on an atherosclerotic diet. Forty-eight rabbits were distributed in six groups. Control group was fed on standard chow for 80 days. The rest were fed with an atherogenic diet for 50 days. After that, a group was sacrificed and the rest were subjected for another extra 30 days on commercial chow alone or supplemented with coenzyme Q(10), squalene or hydroxytyrosol. Atherosclerotic rabbits had higher fibrosis and endothelial activation and lower cellularity in gingival mucosa than controls (P<0.05). Hydroxytyrosol reduced endothelial activation (P<0.05) and squalene additionally decreased fibrosis (P<0.05). Results suggest that gingival vascular changes after the atherosclerotic diet have been reversed by hydroxytyrosol and squalene, natural products from the minor fraction of virgin olive oil.