Effects of Dairy Matrix on the Intestinal, Liver, and Bone Transcriptome of Healthy Rats

Area of Science:

• Nutritional Science
• Molecular Biology
• Gastroenterology

Background:

• Fermentation is a traditional food processing method altering nutrients and bioactive compounds in dairy products.
• The precise mechanisms by which fermented dairy benefits host health are not fully understood.
• Understanding gene expression changes provides insights into the physiological effects of fermented dairy.

Purpose of the Study:

• To investigate the impact of milk and yogurt, with and without prebiotic inulin, on the transcriptome of rat colonic mucosa, liver, and femur.
• To compare the effects of fermented dairy (yogurt) versus non-fermented dairy (milk) on host gene expression.
• To determine the influence of prebiotic supplementation on the effects of dairy consumption.

Main Methods:

• Young male rats were fed diets containing skimmed milk, milk with inulin, yogurt, or yogurt with inulin for 6 weeks.
• Microarray analysis was used to assess differential gene expression in colonic mucosa, liver, and femur.
• Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses were performed.

Main Results:

• Yogurt consumption led to significant changes in gene expression in the colonic mucosa, with 2195 upregulated and 1474 downregulated differentially expressed genes (DEGs) compared to milk.
• Yogurt intake enriched tight junction and immune system-related pathways in the colonic mucosa and metabolic pathways in the liver.
• No significant differences in bone transcriptome were observed between the diet groups.

Conclusions:

• Fermented dairy products, such as yogurt, exert more substantial effects on intestinal gene expression than non-fermented dairy.
• The impact of fermented dairy on gene expression in the gut is more pronounced than that of prebiotic supplementation alone.
• Yogurt consumption influences key pathways in the gut and liver, suggesting broad physiological benefits.