Dairy milk microRNAs resist in vitro digestion in a gastro‐intestinal tract model
Bibliographic record
Abstract
MicroRNAs are small, gene regulatory non‐coding RNA species that are present in large amounts in milk where they seem to be protected against degradative conditions, presumably because of their association with exosomes. We monitored the relative stability of commercial dairy milk microRNAs, under the gastrointestinal (GI) tract conditions that prevails during digestion, and examined their association with extracellular vesicles (EVs). To do so, we used a computer‐controlled TNO in vitro GI model (TIM‐1) and analyzed, by quantitative PCR (qPCR), the level of two milk microRNAs within all GI tract compartments at different time points. MicroRNA‐containing EVs within digested and non‐digested samples were studied by immunoblotting, dynamic light scattering, qPCR and density measurements. We observed that an important proportion of dairy milk bta‐miR‐223 and bta‐miR‐125b withstand digestion under simulated GI tract conditions, with the stomach causing the greater loss in microRNAs. A significant amount of these two microRNAs (~10 8 –10 9 copies/300 ml milk) was detected in the upper small intestine compartments, which supports their bioavailability. A protocol optimized for the enrichment of dairy milk exosomes yielded a 100,000 g pellet fraction positive for the exosomal marker Tumor susceptibility gene‐101 (TSG‐101) and containing bta‐miR‐223 and bta‐miR‐125b. This approach, based on successive ultracentrifugation steps, also revealed the existence of TSG‐101 negative EVs that are larger than exosomes and more enriched in bta‐miR‐223 and bta‐miR‐125b. Our findings indicate that commercial dairy milk contains numerous microRNAs that can resist digestion and are associated mostly with non‐exosomal EVs. Our results strengthen the idea that milk microRNAs are bioactive compounds in dairy milk, support the existence of interspecies transfer of microRNAs based on milk consumption, and challenge our current view of exosomes as the sole carriers of milk‐derived microRNAs. Support or Funding Information This work was supported by Grants No. 319618 and 327522 from the Canadian Institutes of Health Research (CIHR), through the Institute of Genetics (to P.P.).
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.001 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".