Diet composition is important for health, especially during critical periods such as pre-gestation (P), gestation (G), or lactation (L), due to its potential impact on both the mother and the offspring. The Mediterranean diet includes many healthy foods such as whole grains, fruits, vegetables, beans, and nuts, all of them rich in fiber and polyphenols.

The present preclinical study assesses the impact on intestinal gene expression of a diet rich in fiber and polyphenols (HFP diet) during those periods, which, in rats, correspond to 3 weeks each (P, G, or L). Gene expression analysis was performed at the end of lactation using mRNA two-step PCR amplification with random primers and poly-T, followed by library generation and HiSeq X-Ten Illumina sequencing (Seeqplexing).

The results showed a broad number of genes significantly modulated after the HFP diet compared to a reference diet, with higher number of genes modulated when the supplementing period was closer to the analysis day (L>G>P). Notably, genes involved in immune signaling, intestinal absorption, and cell growth were among those significantly affected by the HFP dietary intervention. A diet effect on the expression of key genes such as ferritin, apelin, fibroblast growth factor (FGF)-12, interleukin (IL)-17, and complement proteins, among others, was also found. There was also a unique gene modified in all the intervention periods (Family with Sequence Similarity 17 Member A—FAM17A—which codifies a protein with unknown function), indicating that this molecule may participate in the effects induced by fiber and polyphenols.

Overall, the influence of diet during a 3 week period (P, G, or L) in rats is able to modulate the intestinal gene expression, and, consequently, maternal health, which can ultimately have an indirect impact on the offspring.