Modulation of the peripheral blood transcriptome by the ingestion of probiotic yoghurt and acidified milk in healthy, young men

PLoS One. 2018 Feb 28;13(2):e0192947. doi: 10.1371/journal.pone.0192947. eCollection 2018.

Abstract

The metabolic health benefits of fermented milks have already been investigated using clinical biomarkers but the development of transcriptomic analytics in blood offers an alternative approach that may help to sensitively characterise such effects. We aimed to assess the effects of probiotic yoghurt intake, compared to non-fermented, acidified milk intake, on clinical biomarkers and gene expression in peripheral blood. To this end, a randomised, crossover study was conducted in fourteen healthy, young men to test the two dairy products. For a subset of seven subjects, RNA sequencing was used to measure gene expression in blood collected during postprandial tests and after two weeks daily intake. We found that the postprandial response in insulin was different for probiotic yoghurt as compared to that of acidified milk. Moreover changes in several clinical biomarkers were associated with changes in the expression of genes representing six metabolic genesets. Assessment of the postprandial effects of each dairy product on gene expression by geneset enrichment analysis revealed significant, similar modulation of inflammatory and glycolytic genes after both probiotic yoghurt and acidified milk intake, although distinct kinetic characteristics of the modulation differentiated the dairy products. The aryl hydrocarbon receptor was a major contributor to the down-regulation of the inflammatory genesets and was also positively associated with changes in circulating insulin at 2h after yoghurt intake (p = 0.05). Daily intake of the dairy products showed little effect on the fasting blood transcriptome. Probiotic yoghurt and acidified milk appear to affect similar gene pathways during the postprandial phase but differences in the timing and the extent of this modulation may lead to different physiological consequences. The functional relevance of these differences in gene expression is supported by their associations with circulating biomarkers.

Publication types

  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Animals
  • Appetite
  • Biomarkers / blood
  • Cross-Over Studies
  • Cultured Milk Products
  • Double-Blind Method
  • Gene Expression Profiling
  • Genetic Markers
  • Humans
  • Male
  • Milk*
  • Postprandial Period / genetics
  • Probiotics*
  • RNA / blood
  • RNA / genetics
  • Transcriptome / genetics*
  • Yogurt*
  • Young Adult

Substances

  • Biomarkers
  • Genetic Markers
  • RNA

Grants and funding

This work was supported in part by the Swiss National Science Foundation in the frame of the national research program “Healthy nutrition and sustainable food production” (NRP69) hosting the JPI HDHL project EU Food Biomarkers Alliance (FoodBAll). Endotoxin assays were financed by a collaboration with the University of Warwick using a grant received from the Higher Education Innovation Fund 5. These funders had no role in the study design, data collection and analysis, decision to publish or preparation of the manuscript.