Location: Children's Nutrition Research Center
2023 Annual Report
Objectives
Objective 1: To define the effect of pregnancy and lactation on carotenoid and vitamin A status and markers of bioactivity in diverse healthy weight and obese women.
Subobjective 1A: We will define the changes in plasma, skin, and macular (a marker of brain lutein and zeaxanthin) carotenoid status changes over the course of pregnancy and lactation in healthy and obese women. This will allow us to define the dietary, anthropometric, and genetic determinants of carotenoid status.
Subobjective 1B: We will determine if carotenoid status is associated with markers of inflammation and cognitive function in pregnant and lactating women.
Subobjective 1C: We will define the relationship between maternal and infant carotenoid status at birth and 8 wk in lean and obese mothers.
Objective 2: To determine the pharmacokinetic basis for why adiposity affects breast milk carotenoid composition.
Subobjective 2A: We will define the plasma and breast milk pharmacokinetics of 2H-labeled lutein and beta-carotene in normal and obese lactating mothers.
Subobjective 2B: We will determine the bioavailability of 2H-labeled lutein and beta-carotene from intrinsically-labeled spinach in lactating mothers.
Approach
Women with either a pre-pregnancy normal or obese BMI will be recruited in the first trimester of pregnancy. Subjects will undergo a dietary, carotenoid status, body mass and composition, physical activity and sleep, and cognitive function assessments at 24 and 34 weeks of gestation and at 8 weeks post-partum. At the post-natal visit, mothers will participate in the same tests, will be asked to provide a breast milk sample and infant anthropometrics and carotenoid status will be assessed by blood sampling and dermal carotenoid intensity measures. Maternal and cord blood will be collected upon delivery for carotenoid analysis. Through these studies we will determine if maternal carotenoid status changes over the course of pregnancy and if that change can be explained by changes in maternal carotenoid intake and body composition.
Progress Report
Progress this year was made on multiple fronts related to our proposed objectives. The COVID-19 risk was lessened this year and we were able to resume in-person study visits with pregnant participants, new mothers, and infants. To this end we have recruited and are following 34 participants for Objective 1 and are in a good position to complete recruitment and data collection in the coming year. Also related to the goals of the project we were able to pursue several other related analyses of already collected data and specimens to support the study of carotenoid absorption and bioactivity during pregnancy and early life.
Related to Objective 2, we collaborated with other Children’s Nutrition Research Center researchers to study the feasibility of studying the piglet model of infant carotenoid absorption and metabolism. Currently, we largely rely on human studies of maternal and infant nutrition to study carotenoids, and we need relevant animal models to study these questions related to carotenoid absorption and metabolism. We found that piglets absorb carotenoids from donor human milk and infant formula in patterns similar to that observed in human infants. This initial feasibility analysis opens up new, innovative methods to study carotenoid nutrition.
Related to Objectives 1 & 2, we are collaborating with researchers from the ARS Grand Forks Human Nutrition Research Center to study the influence of adult human genetic variation on carotenoid absorption using previously collected data. We also collaborated with researchers at the University of Houston to determine the plausibility of optical skin carotenoid measurements as a biomarker of toddler carotenoid and fruit and vegetable consumption using data collected from a randomized controlled trial. We are also studying nationally representative data collected by the Centers for Disease Control to learn what the usual carotenoid intake is of children 0-24 months of age, and the contribution of carotenoid intake to these children’s vitamin A requirements. These analyses are underway. Lastly, we are examining the validity of different survey tools and databases for determining infant carotenoid intakes. In summary, we have devoted much time recruiting and collecting data from our Objective 1 study participants and look forward to completing this portion of the study. While that study is being conducted, we have worked to pursue secondary data analyses to answer questions related to the project theme of maternal and early life carotenoid nutrition.
Accomplishments
1. Establishing the feasibility and reliability of optical skin measurements to assess infant dietary intake. To develop evidence-based guidelines for infant nutrition, it is important to have an accurate understanding of the relationship between infant’s food intake and their health. Determining what infants eat can be challenging due to their inability to remember or tell you what they eat. Dietary biomarkers are measurements of a person’s body or specimens that can tell us information about what they eat. Optical measurements of skin carotenoids, colorful compounds found in fruits and vegetables, are being used as biomarkers of older children’s and adult’s fruit and vegetable intake. Researchers at the Children's Nutrition Research Center in Houston, Texas, found that optical skin carotenoid measurements can also be reliably conducted on infant fingers and the heels of their feet at 4, 6, and 8 months old. This measurement provides a new tool for researchers to continue to further study as a biomarker of infant nutrition.
