Alperujo extract, hydroxytyrosol, and 3,4-dihydroxyphenylglycol are bioavailable and have antioxidant properties in vitamin E-deficient rats—a proteomics and network analysis approach
Article first published online: 30 MAY 2012
© 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
Molecular Nutrition & Food Research
Special Issue: Nutrition and Atherosclerosis
Volume 56, Issue 7, pages 1131–1147, July 2012
How to Cite
Rodríguez-Gutiérrez, G., Duthie, G. G., Wood, S., Morrice, P., Nicol, F., Reid, M., Cantlay, L. L., Kelder, T., Horgan, G. W., Fernández-Bolaños Guzmán, J. and de Roos, B. (2012), Alperujo extract, hydroxytyrosol, and 3,4-dihydroxyphenylglycol are bioavailable and have antioxidant properties in vitamin E-deficient rats—a proteomics and network analysis approach. Mol. Nutr. Food Res., 56: 1131–1147. doi: 10.1002/mnfr.201100808
- Issue published online: 4 JUL 2012
- Article first published online: 30 MAY 2012
- Manuscript Accepted: 12 MAR 2012
- Manuscript Revised: 24 FEB 2012
- Manuscript Received: 9 DEC 2011
- Scottish Government's Rural and Environment Science and Analytical Services Division
Olive products are rich in phenolic compounds, which are natural antioxidants in vitro. We tested the in vivo effects of alperujo, an olive production by-product, as well as hydroxytyrosol and 3,4-dihydroxyphenylglycol (DHPG) isolated from alperujo, on indices and pathways of oxidative and metabolic stress in a vitamin E-deficient rat model.
Methods and results
Rats were fed a vitamin E-deficient diet for 10 weeks, followed by this diet supplemented with either 100 mg/kg diet dα-tocopherol, alperujo extract, hydroxytyrosol, or 10 mg/kg diet DHPG, for a further 2 weeks. We detected alperujo phenolics in tissues and blood, indicating they are bioavailable. Alperujo extract partially ameliorated elevated plasma levels of thiobarbituric acid reactive substances and also lowered plasma cholesterol levels, whereas hydroxytyrosol increased plasma triglyceride levels. Proteomics and subsequent network analysis revealed that hepatic mitochondrial aldehyde dehydrogenase (ALDH2), of which protein and activity levels were regulated by dα-tocopherol and olive phenolics, represents a novel central regulatory protein hub affected by the dietary interventions.
The in vivo free radical scavenging properties of olive phenolics appear relatively modest in our model. But alternative mechanisms, including regulation of ALDH2, may represent relevant antioxidant mechanisms by which dietary olive phenolics could have beneficial impact on cardiovascular health.