Health Benefits of High-Phenolic Olive Oils Decoded through Gene Expressions

Summary

The Mediterranean diet, espe­cially due to high lev­els of fatty acids in extra vir­gin olive oil, pro­vides pro­tec­tion against car­dio­vas­cu­lar dis­ease and can­cer by improv­ing lipid pro­files and reduc­ing inflam­ma­tion. A recent study in Italy found that the health ben­e­fits of extra vir­gin olive oil, par­tic­u­larly in improv­ing insulin sen­si­tiv­ity and glu­cose metab­o­lism, are attrib­uted to the polyphe­nol com­po­nents rather than the fatty acids.

The Mediterranean diet (MeD) is well-known to impart con­sid­er­able pro­tec­tion against the occur­rence of car­dio­vas­cu­lar dis­ease and can­cer. In par­tic­u­lar, the plethora of pro­tec­tive health ben­e­fits of the MeD includ­ing improved lipid pro­file and reduced inflam­ma­tion has been linked largely to the high lev­els of fatty acid con­tent found in extra vir­gin olive oil.

However, there is still no clar­ity as to which com­po­nents ofex­tra vir­gin olive oil are respon­si­ble for the reg­u­la­tion of genes involved in inflam­ma­tory, anti-oxi­dant or immune path­ways.
See Also:Olive Oil Health Benefits
In addi­tion, while there are a few human clin­i­cal stud­ies on the acute effect of high intake ofex­tra vir­gin olive oil on gene expres­sion changes, to date there are no reports on the­ex­tra vir­gin olive oil effect on the whole tran­scrip­tome expres­sion pro­file (genome and RNA).

The reg­u­la­tion of nor­mal bio­log­i­cal func­tion at the cel­lu­lar and mol­e­c­u­lar lev­els is through small RNA sequences known as MicroRNA (miRNA) that have been promis­ing as ther­a­peu­tic tar­gets for cer­tain dis­eases. Advances in whole genome mRNA (tran­scrip­tome) sequenc­ing has led to com­pre­hen­sive analy­sis of RNA tran­scripts in a given tis­sue sam­ple.

In a recent study pub­lished in Biochim Biophys Acta, a col­lab­o­ra­tive group of researchers in Italy took advan­tage of tran­scrip­tome sequenc­ing tech­nol­ogy and inves­ti­gated the health pro­tec­tive mech­a­nisms of extra vir­gin olive oil by iden­ti­fy­ing gene expres­sion sig­na­ture after an acute con­sump­tion ofex­tra vir­gin olive oil in both healthy vol­un­teers and meta­bolic syn­drome patients.

The study involved con­sump­tion of a sin­gle dose of low- or high-polyphe­nol extra vir­gin olive oil (50ml) by healthy vol­un­teers and patients with meta­bolic syn­drome on dif­fer­ent occa­sions. The selected EVOOs were sim­i­lar in fatty acid but dif­fered in polyphe­nol com­po­si­tions.

The sci­en­tists found that acute polyphe­nol-rich olive oil effects in healthy par­tic­i­pants led to marked improve­ment in insulin sen­si­tiv­ity and glu­cose metab­o­lism, at the same time sup­port­ing miRNA and gene expres­sion in inflam­ma­tion and immune responses.

On the con­trary, these bio­chem­i­cal and mol­e­c­u­lar effects ofex­tra vir­gin olive oil were largely absent in patients affected by meta­bolic syn­drome or par­tic­i­pants who con­sumed low-polyphe­nolex­tra vir­gin olive oil sug­ges­tive of a puta­tive role for the phe­no­lic com­po­nent.

Next, the researchers sought to deter­mine whether such ben­e­fits ofex­tra vir­gin olive oil in healthy vol­un­teers were attrib­uted to the polyphe­nols or the fatty acid com­po­nents of EVOO.

They found that in vol­un­teers who con­sumed polyphe­nol-rich olive oil, there was a sig­nif­i­cant change in the expres­sion of genes pre­vi­ously know to be acti­vated by fatty acids than any oth­erex­tra vir­gin olive oil com­po­nents. In con­trast, the major­ity of gene expres­sions remained the same in indi­vid­u­als after inges­tion of extra vir­gin olive oil low in polyphe­nols.

The sci­en­tists fur­ther demon­strated that the effects of EVOO high in polyphe­nols at the mol­e­c­u­lar level sup­ported reg­u­la­tion of miRNA exert­ing var­i­ous effects on inflam­ma­tion, can­cer and insulin resis­tance.

The key mes­sage of this study was that ​“the intake ofex­tra vir­gin olive oil con­tain­ing high phe­nols improves insulin sen­si­tiv­ity and mod­u­lates dif­fer­ent path­ways in inflam­ma­tory cells of healthy sub­jects; most of these changes point to a ben­e­fi­cial role ofex­tra vir­gin olive oil in pro­mot­ing health toward its anti-inflam­ma­tory, anti-can­cer, and antiox­i­dant prop­er­ties.”

• OMICS


• Biochim Biophys Acta