Milk exosomal microRNAs: friend or foe?—a narrative review

Abstract

Background and Objective: Milk exosomes (MEX) and their inherent microRNAs (miRs) were recently promoted as promising effectors and drug carrier systems for the treatment of various chronic human diseases. It is the intention of this review to provide a comprehensive view on the potential beneficial and adverse health effects of MEX miRs.Methods: English literature published between 1990-2022 were searched using the PubMed database focusing on publications including human and bovine MEX, milk extracellular vesicles (EVs), miRs, and reported beneficial and adverse effects of MEX miRs. KeyContent and Findings: MEX are regarded as signalosomes produced under control of the lactation genome to support species-specific growth of the offspring during the lactation period. Physiologically, mammals are not exposed to MEX miRs after the lactation period. MEX miRs are important for epigenetic postnatal programming and tissue maturation. Direct and translational evidence indicates that MEX miRs are involved in p53-mediated transcription, DNA methyltransferase-regulated gene silencing as well as Polycomb repressive complex-mediated gene repression and chromatin remodeling. MEX miRs are deficient in artificial formula, but may accidentally modify human gene expression by consumption of pasteurized cow milk. The continuous impact of bovine MEX miRs on the human epigenome and epitranscriptome remains a matter of concern.Conclusions: MEX miRs are supportive for the growing neonate, whereas continuous exposure of adult humans to bovine MEX miRs may promote obesity, diabetes, cancer and neurodegeneration. Bovine MEX miRs should be removed from the human food chain of adults. The efficacy and long-term safety of MEX miRs has to be carefully assessed in future studies before bovine MEX could be introduced for therapeutic purposes.

Milk Exosomal microRNAs: Postnatal Promoters of β Cell Proliferation but Potential Inducers of β Cell De-Differentiation in Adult Life

“…Preterm MEX miR composition may influence early postnatal development of the pancreatic β-cells of preterm infants. Remarkably, MECP2 is a highly conserved target of miR-22, miR-148a, and miR-30 [ 371 , 372 ]. MECP2 is important for gene silencing and guides DNMT1 to CpG sides for DNA methylation [ 109 ], which generally suppresses gene transcription [ 184 ].…”

Innovation waves: Analysis and modeling of patents on ultrasound applications in food processing

“…Regarding the dairy segment, most documents are focused on changes in technological properties. We can highlight the following patents: US2014302205A1—Method and device for producing commercial milk and milk having reduced biological activity of exosomal ribonucleic acids (structures contributing to the development of diseases; Melnik, 2014); WO2009079691A1—Processing of dairy ingredients by ultrasonication (Ashokkumar et al, 2009) (method for altering viscosity and gelation properties); US2011268852A1—Methods to provide for whey protein solutions with low turbidity; Martini & Walsh, 2011; and RU2251870C2—Process and machine for ultrasound treatment of liquid food mixtures (method for controlling the size of ice crystals in ice cream; Kvasenkov & Dobrovol'skij, 2005).…”

Potential Pathogenic Impact of Cow’s Milk Consumption and Bovine Milk-Derived Exosomal MicroRNAs in Diffuse Large B-Cell Lymphoma

“…Whereas MDEs and their miRs are of key importance for neonatal development [ 578 , 579 ], MDEs may exert pathogenic effects in adults [ 579 ]. In this light, bovine MDEs should be regarded as pathogens that have to be excluded from the human food chain [ 580 , 581 ]. With regard to DLBCL pathogenesis, we are concerned about recent recommendations promoting bovine miR-155-rich colostrum for “immune-nutrition” in elderly subjects [ 582 ] as well as bovine MDEs as “health-improving bioactive ingredients” in the context of human nutrition [ 583 ].…”