Analysis of gene expression changes in whole blood samples from young men after acute or short-term intake of probiotic yoghurt compared to acidified milk

Fermented dairy milks have been associated with many health benefits including the regulation of metabolic dysfunction. Different circulating clinical biomarkers have been used to explore the effect of fermented milks on metabolic health but the development of whole blood transcriptomics has recently been proposed as a source of novel biomarkers for this health outcome. In a randomised, cross-over study, we evaluate the changes in the whole blood transcriptome after the intake of a probiotic yoghurt compared to a milk acidified with gluconic acid in seven healthy young men. The effects of the dairy foods on whole blood gene expression were assessed at three time points during a 6 h postprandial test (800g single dose) and in the fasting state after a daily intake of the products over two-weeks (400g/d). RNA was extracted from Paxgene ® whole blood samples and sequenced on the Illumina HiSeq platform. A crossover design was used to compare the postprandial and short-term response to the intake of two dairy products in seven healthy young men. A total of 77 samples were collected. For each volunteer one samples was taken under baseline condition (run-in), four samples were taken for the postprandial assessment ('acute') of the two products (0h, 2h, 4h, 6h), and one sample was taken after two-weeks daily intake of each dairy product.