Location: Arkansas Children's Nutrition Center
Project Number: 6026-51000-012-008-S
Project Type: Non-Assistance Cooperative Agreement
Start Date: Aug 1, 2022
End Date: Jul 31, 2027
To examine the effects of early life stress on immune response markers in various tissues (i.e., bone, adipose, muscle and heart).
We hypothesized that early life stress during lactation impacts gut health resulting in chronic inflammation that will interfere with optimal function of these tissues. The animal study will be conducted at USDA-ARS Arkansas Children's Nutrition Center. Pregnant rats will be allowed to deliver pups without intervention. On postnatal day (PND) 2, the litters will be randomly assigned and transferred to either an “impoverished” cage or a standard cage at which point the litter will be left undisturbed and the cage unchanged for 7 days. On postnatal days 2, 10, and 22, we will obtain 1.0 ml milk sample from each dam at the time of planned separation from the dam. Postnatal food consumption will be measured, but not restricted. We will weigh the food provided during routine cage changes and daily animal checks. Dams and pups will be weighed at the time of routine cage changes. To determine how early life stress during lactation impacts bone health, the Collaborator's team will measure bone quality (bone mineral content, bone mineral density, and microarchitecture) and gene expression of inflammatory markers. Furthermore, adipose tissue- gene expression (inflammatory markers-IL6, TNF-alpha, uncoupling protein, glucocorticoid receptor, leptin, glucose transporter- GLUT4), histological examination (adipocyte size & lipid density), muscle - gene expression (inflammatory markers, glucose transporter GLUT 4) and heart and aorta - gene expression of inflammatory and vascular dysfunction markers will be measured. ARS SY's team will assess gut microbiota composition to associate the bone, muscle, heart, and adipose tissue outcomes.