GSE176118
Effect of lactational high fat diet and metformin on mid-lactation murine mammary gland gene expression
Maternal health and diet can have important consequences for offspring nutrition and metabolic health. Signals are communicated from the mother to the infant during lactation through milk via macronutrients, hormones and bioactive molecules. In this study we designed experiments to probe the mother-milk-infant triad in the condition of normal maternal health and upon exposure to high fat diet (HFD) with or without concurrent metformin exposure. We examined maternal characteristics, milk composition and offspring metabolic parameters on postnatal day 16, prior to offspring beginning to wean. We found that lactational HFD increased maternal adipose tissue, mammary gland adipocytes, and altered milk lipid composition causing a higher amount of n-6 long chain fatty acids and lower n-3. Offspring of HFD dams were heavier with more body fat during suckling. Metformin exposure decreased maternal glucose and several amino acids. Offspring of met dams were smaller during suckling. Gene expression in the lactating mammary glands was impacted to a greater extent by metformin but both metformin and HFD altered genes related to muscle contraction, indicating that these genes may be more susceptible to lactational stressors. Our study demonstrates the impact of common maternal exposures during lactation on milk composition, mammary gland function and offspring growth with metformin having little capacity to recuse from the effects of a maternal HFD during lactation. Overall design: n=4 per group from 4 groups