HEALTH NEWS

Study Title:

Olive Oil, Inflammation, and the Metabolic Syndrome

Study Abstract

Background
Previous studies have shown that acute intake of high-phenol virgin olive oil reduces pro-inflammatory, pro-oxidant and pro-thrombotic markers compared with low phenols virgin olive oil, but it remains unclear if the effects attributed to its phenolic fraction are exerted at the transcriptional level in vivo. To achieve this goal, we aimed at identifying in humans those genes which undergo expression changes mediated by virgin olive oil phenolic compounds.

Results
Postprandial gene expression microarray analysis was performed on peripheral blood mononuclear cells at the postprandial period. Two virgin olive oil-based breakfasts with high (398 ppm) and low (70 ppm) content of phenolic compounds were administered to 20 patients with metabolic syndrome following a double-blinded random crossover design. To eliminate the potential effect that might exist in their usual dietary habits, all subjects followed a similar low-fat, carbohydrate rich diet during the study period. Microarray analysis identified 98 differentially expressed genes (79 underexpressed and 19 overexpressed) when comparing the intake of phenol-rich olive oil with the low-phenol olive oil. Many of those genes are linked to obesity, dyslipemia and type 2 diabetes mellitus. Among these, several genes are involved in inflammatory processes mediated by transcription factor NF-kappa B, activator protein-1 transcription factor complex AP-1, cytokines, mitogen-activated protein kinases MAPKs or arachidonic acid pathways.

Conclusion
This study shows that intake of a breakfast based in virgin olive oil rich in phenol compounds is able to repress the in vivo expression of several pro-inflammatory genes, thereby switching the activity of peripheral blood mononuclear cells to a less deleterious inflammatory profile. These results provide at least a partial molecular basis for the reduced risk of cardiovascular disease observed in Mediterranean countries, where virgin olive oil represents the main source of dietary fat. Admittedly, other lifestyle factors are also likely to contribute to lowered risk of cardiovascular disease in this region.

Study Information

Antonio Camargo , Juan Ruano , Juan M Fernandez , Laurence D Parnell , Anabel Jimenez , Monica Santos-Gonzalez , Carmen Marin , Pablo Perez-Martinez , Marino Uceda , Jose Lopez-Miranda and Francisco Perez-Jimenez
Gene expression changes in mononuclear cells from patients with metabolic syndrome after acute intake of phenol-rich virgin olive oil.
BMC Genomics
2010 April
Lipids and Atherosclerosis Research Unit. Spain.