title: Determination of the potential bioavailability of plant microRNAs using a simulated human digestion process.
abstract: METHODS
  The "dietary xenomiR hypothesis" proposes that microRNAs (miRNAs) in foodstuffs survive transit through the mammalian gastrointestinal tract and pass into cells intact to affect gene regulation. However, debate continues as to whether dietary intake poses a feasible route for such exogenous gene regulators. Understanding on miRNA levels during pretreatments of human diet is essential to test their bioavailability during digestion. This study makes the novel first use of an in vitro method to eliminate the inherent complexities and variability of in vivo approaches used to test this hypothesis.
  
  
  RESULTS
  Plant miRNA levels in soybean and rice were measured during storage, processing, cooking, and early digestion using real-time PCR. We have demonstrated for the first time that storage, processing, and cooking does not abolish the plant miRNAs present in the foodstuffs. In addition, utilizing a simulated human digestion system revealed significant plant miRNA bioavailability after early stage digestion for 75 min. Attenuation of plant messenger RNA and synthetic miRNA was observed under these conditions.
  
  
  CONCLUSIONS
  Even after an extensive pretreatment, plant-derived miRNA, delivered by typical dietary ingestion, has a robustness that could make them bioavailable for uptake during early digestion. The potential benefit of these regulatory molecules in pharma nutrition could be explored further.
authors.affiliation: Strathclyde Institute of Pharmacy and Biomedical Science, University of Strathclyde, Glasgow, UK.
authors.forename: Anna
authors.initials: A
authors.lastname: Philip
authors.affiliation: Strathclyde Institute of Pharmacy and Biomedical Science, University of Strathclyde, Glasgow, UK.
authors.forename: Valerie A
authors.initials: VA
authors.lastname: Ferro
authors.affiliation: Strathclyde Institute of Pharmacy and Biomedical Science, University of Strathclyde, Glasgow, UK.
authors.forename: Rothwelle J
authors.initials: RJ
authors.lastname: Tate
mesh_terms: D001682:Biological Availability; D003296:Cooking; D004063:Digestion; D006358:Hot Temperature; D006801:Humans; D035683:MicroRNAs / Q000737:chemistry / Q000493:pharmacokinetics*; D012275:Oryza / Q000235:genetics*; D018749:RNA, Plant / Q000737:chemistry / Q000493:pharmacokinetics*; D060888:Real-Time Polymerase Chain Reaction; D012260:Ribonucleases / Q000737:chemistry; D013025:Glycine max / Q000235:genetics*
chemical_list: D035683:MicroRNAs; D018749:RNA, Plant; D012260:Ribonucleases
keywords: Cross-kingdom regulation; Diet; MicroRNA; Nutraceutical; Simulated digestion