Submitted to: Biomed Central (BMC) Genomics
Publication Type: Peer reviewed journal
Publication Acceptance Date: 4/20/2010
Publication Date: 4/20/2010
Citation: Camargo, A., Ruano, J., Fernandez, J.M., Parnell, L.D., Jimenez, A., Santos-Gonzalez, M., Marin, C., Perez-Martinez, P., Uceda, M., Lopez-Miranda, J., Perez-Jimenez, F. 2010. Gene expression changes in peripheral blood mononuclear cells from patients with metabolic syndrome after acute intake of phenol-rich virgin olive oil. Biomed Central (BMC) Genomics. 11:253-267. Interpretive Summary: Some studies have shown that heightened intake of phenol-rich virgin olive oil reduces pro-inflammatory, pro-oxidant and pro-(blood) clotting states, but it is still not certain if these effects are the result of the phenolic compounds acting to alter gene activity. We interrogated the expression of over 20,000 human genes on peripheral blood mononuclear cells during the after-meal period. This meal consisted of an olive oil-based breakfast with either high or low levels of phenolic compounds in the olive oil and was given to twenty patients suffering metabolic syndrome, a collection of abnormalities in weight, blood pressure and blood lipid measures. The gene activity results indicated that 79 genes are turned down and 19 are turned up by the high-phenol olive oil. Many of those genes have been linked recently to obesity, dyslipidemia, type 2 diabetes mellitus and coronary disease. Among these, several genes are also involved in inflammatory processes and are themselves regulated by well characterized regulators of the inflammation response. In conclusion, part of the beneficial effects of a virgin olive oil phenolic fraction could be exerted by modulating the activity of pro-inflammatory genes.
Technical Abstract: Some studies have shown that acute intake of high-phenol virgin olive oil reduces pro-inflammatory, pro-oxidant and pro-thrombotic states, but it remains unclear if the effects attributed to its phenolic fraction are exerted at the transcriptional level in vivo. 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 twenty patients with metabolic syndrome following a double-blinded random crossover design. Microarray analysis identified 98 differentially expressed genes (79 underexpressed and 19 overexpressed) when comparing the acute intake of phenol-rich olive oil with the low-phenol olive oil. Many of those genes have been linked recently, through GWA studies and animal models, to obesity, dyslipidemia, type 2 diabetes mellitus and coronary disease. Among these, several genes are involved in inflammatory processes mediated by transcription factor NFkappa B, jun N-terminal kinase JNK, activator protein-1 transcription factor complex AP-1, cytokines, mitogen-activated protein kinases MAPKs or arachidonic acid pathways. In conclusion, part of the beneficial effects of a virgin olive oil phenolic fraction could be exerted by modulating the expression of pro-inflammatory genes.