Exogenous extracellular vesicles and microRNAs cargo can be considered micronutrients?
It is well recognized that diet components are important genomic regulators even if RNA transcripts as messenger RNAs (mRNAs) represent less than 2% of the whole genome. In the old-fashioned understanding of genetics, mRNAs are encoded to synthesize a specific protein. Nevertheless, this representation has substantially increased in complexity with the discovery of non-coding RNAs in which microRNAs (miRNAs) gained significant attention in the past 15 years - because its discovery was awarded by the Nobel Prize in physiology or medicine in 2006 to Andrew Z. Fire and Craig C. Mello. MiRNAs are small (18 to 25 nucleotides-long), endogenous non-coding RNA-nucleotide evolutionary conserved, shown to modulate gene expression at the posttranscriptional level through the binding to the complementary sequences of their target mRNAs at the 3' untranslated regions (3' UTRs) (1,2). Based on the interactions between the 3′ UTR of mRNAs, miRNAs can control numerous genes' expression levels. MiRNAs are secreted in lipid bilayer-delimited nanoparticles called extracellular vesicles (EVs), along with proteins and other biomolecules with no replication ability. EVs include microvesicles, apoptotic bodies, and exosomes (Exo), a unique subpopulation of nanosized, spherical membrane vesicles with sizes between 30 and 150 nm. Therefore, EVs and Exo represent a new paradigm in cell biology and medicine, with the idea that the available content may be directly delivered to cells (3).