Home / Nieuws / ...

Olijfolie tegen borstkanker en aderverkalking*
Uit twee Spaanse studies blijken de grote voordelen van het regelmatig eten van olijfolie. In de ene studie blijkt dat hoe olijfolie in tegenstelling tot andere plantaardige oliën het lichaam beschermt tegen borstkanker. Oliën rijk aan omega-6 vetzuren verergeren zelfs een tumor. Olijfolie zorgt voor goedaardige tumoren en laat tegelijkertijd de activiteit van een oncogen (p21RAS) afnemen. Oncogenen zorgen voor ongecontroleerde celdeling en groei van tumoren. In de tweede studie blijkt dat extra virgin olijfolie, rijk aan polyfenolen leidt tot een duidelijk lagere genexpressie van genen die met aderverkalking te maken hebben. In deze studie werden de deelnemers in drie voedingsgroepen verdeeld. De eerste groep kreeg een mediterraandieet met extra virgin olijfolie, de tweede groep een mediterraandieet met gewone olijfolie en de derde groep een normaal dieet. Voornamelijk in de eerste groep waren de grote voordelen duidelijk zichtbaar.
A Key Mechanism Links Virgin Olive Oil To Protection Against Breast Cancer
Researchers at Universitat Autonoma de Barcelona, led by Dr Eduard Escrich, have discovered a key mechanism by which virgin olive oil, in contrast to other vegetable oils, protects the body against breast cancer.
The UAB researchers have decoded a complete cascade of signals within breast tumour cells activated by virgin olive oil, and have concluded that benefits include decrease in the activity of the oncogene p21Ras, changes in protein signaling pathways, stimulation of tumour cell death and prevention of DNA damage. The study has been carried out in an experimental model and researchers have already begun a new study with human cell lines.
Breast cancer is the most common type of cancer in Western countries. Research carried out with animal models demonstrate that a diet rich in fats is directly related to the incidence of cancer. Some types of fats however can play a protective role against the development of these tumours. Such is the case of virgin olive oil, rich in oleic acid, a mono-unsaturated fatty acid, and containing several bioactive compounds such as antioxidants. A moderate and regular intake of virgin olive oil, characteristic of the Mediterranean diet, is associated with low incidences of specific types of cancer, including breast cancer, as well as with having a protective role against coronary diseases and other health problems.
The study carried out by UAB researchers decoded the mechanisms operating within the tumour cell and induced by the intake of olive oil, in comparison to those activated by corn oil, rich in n-6 polyunsaturated fatty acids, which increase the aggressiveness of tumours.
Scientists demonstrated that virgin olive oil is associated with higher incidences of benign breast tumours and at the same time with a decrease in the activity of the p21Ras oncogene, which spurs uncontrolled cell proliferation and stimulates the growth of tumours. In addition, olive oil suppresses the activity of some proteins, such as the AKT, essential for the survival of cells since they prevent apoptosis, the cell's "suicide" programme. Between proliferation and apoptosis in tumour cells, these effects tip the balance towards cell death, thereby slowing the growth of tumours.
Another result obtained by researchers is the protection of DNA in the cell nucleus. Cells from animals fed a diet rich in virgin olive oil contained less DNA lesions than those fed a control diet.
Scientists of the UAB Breast Cancer Study Multidisciplinary Group (GMECM) have spent over twenty years working to determine the effects fats have on breast cancer, and in particular the effects of virgin olive oil. Previous studies of the group revealed the beneficial effects of this component of the human diet on the clinical conduct of mammary tumours and on their histological grade (malignancy). Scientists also described several molecular mechanisms producing these effects and in 2004 the same group was the one to identify the four genes involved in the effects dietary fats have on experimental breast cancer. The mechanism recently discovered was published in the journal Carcinogenesis.
Source: Universitat Autònoma de Barcelona

Olive oil, Mediterranean diet modify expression of atherosclerosis-related genes
New research in the FASEB Journal suggests that the polyphenols in virgin olive oil modify the expression of atherosclerosis-related genes, leading to health benefits
Everyone knows olive oil and a Mediterranean diet are associated with a lower risk for cardiovascular disease, but a new research report published in the print issue of the FASEB Journal (http://www.fasebj.org) offers a surprising reason why: These foods change how genes associated with atherosclerosis function. 
"Knowing which genes can be modulated by diet in a healthy way can help people select healthy diets," said Maria Isabel Covas, D.Pharm., Ph.D., a researcher involved in the work from the Cardiovascular Risk and Nutrition Research Group at the Institut Municipal d'Investigacio Medica in Barcelona, Spain. "It is also a first step for future nutritional therapies with selected foods." 
Scientists worked with three groups of healthy volunteers. The first group consumed a traditional Mediterranean diet with virgin olive oil rich in polyphenols. The second group consumed a traditional Mediterranean diet with an olive oil low in polyphenols. The third group followed their habitual diet. After three months, the first group had a down-regulation in the expression of atherosclerosis-related genes in their peripheral blood mononuclear cells. Additionally, the olive oil polyphenols made a significant impact on the expression of genetic changes influencing coronary heart disease. Results also showed that the consumption of virgin olive oil in conjunction with a Mediterranean diet can positively impact lipid and DNA oxidation, insulin resistance, inflammation, carcinogenesis, and tumor suppression. 
"This study is ground breaking because it shows that olive oil and a Mediterranean diet affect our bodies in a far more significant way than previously believed," said Gerald Weissmann, M.D., Editor-in-Chief of the FASEB Journal. "Not only does this research offer more support for encouraging people to change their eating habits, it is an important first step toward identifying drug targets that affect how our genes express themselves." 
Source: Federation of American Societies for Experimental Biology (September 2010)