22 - Human Milk Oligosaccharide (HMO) Changes as a Function of Maternal Vitamin D (VITD) Status: Post Hoc Analysis of NICHD VITD Lactation Study

Saturday, April 29, 2023

3:30 PM – 6:00 PM ET

Poster Number: 22
Publication Number: 22.201

Grace G Pouch, Medical University of South Carolina College of Medicine, Charleston, SC, United States; Corinne Karch, MUSC Children's Hospital, Charleston, SC, United States; Myla Ebeling, Medical University of South Carolina College of Medicine, Charleston, SC, United States; Judith Shary, Medical University of SC, Charleston, SC, United States; Lars Bode, University of California, San Diego School of Medicine, La Jolla, CA, United States; Katherine E. Chetta, Medical University of South Carolina College of Medicine, Charleston, SC, United States; John E. Baatz, Medical University of South Carolina College of Medicine, Charleston, SC, United States; Carol L.. Wagner, Medical University of South Carolina College of Medicine, Charleston, SC, United States

Presenting Author(s)

Grace G Pouch, B.S. (she/her/hers)

Medical Student
Medical University of South Carolina College of Medicine
Charleston, South Carolina, United States

Background:

There is a lack of understanding about the influence of vitD on the composition of breast milk and how it may affect the immune development of the breastfeeding infant. Based on the nature of vitD and its pleiotropic effect on numerous genes, cells, including immune cells, and bacteria, we hypothesized that women who are vitD deficient (VDD) will have milk that differs in its composition of prebiotic oligosaccharides (HMOs) and bacteria.

Objective:

Determine whether maternal vitD status affects the HMO profile of breast milk as a function of maternal secretor status.

Design/Methods:

Women (n=61) participating in a lactation vitD pilot study received a daily multivitamin containing 400 IU and either placebo (O IU vitD) or 6000 IU vitD. Maternal 25(OH)D as the measure of vitD status was measured monthly. High performance liquid chromatography was used to measure the concentration of 19 HMOs classified as HMO-bound fucose (Fuc) and HMO-bound sialic acid (Sia). Maternal secretor status was defined by the presence or absence or near absence of 2’FL or LNFP I. The data were analyzed by Spearman and Pearson correlation and by linear regression using SAS 9.4 (Cary, NC). We performed summary statistics for HMO and 25OHD labs and Spearman and Pearson correlation with 25OHD and HMO, and linear regression modeling 25OHD and HMO stratified by secretor status. Bonferonni corrections were made for multiple comparisons.

Results:

Among secretor mothers, maternal 25(OH)D was associated with Lacto-N-hexose (LNH) at 4 months (p=0.035) and the change in maternal 25(OH)D between 1 and 4 months was also associated with Lacto-N-hexose (LNH; p=0.0335). Among non-secretor mothers, maternal baseline 25(OH)D was associated with 3 fucosyllactose (3FL; p=0.036). The change in maternal 25(OH)D between 1 and 4 months was associated with total HMO-bound fucose (p=0.037). Between 1 and 4 months, the percent change in 25(OH)D was associated with the percent change in total HMO-bound fucose (p=0.036) and with percent change in disialyl-lacto-N-hexose (DSLNH; p=0.0349). At 4 months, maternal 25(OH)D and percent change in total HMO-bound fucose (p=0.0316) and difucosyllacto-N-tetrose (DFLNT; p=0.0414). When combining secretor and non-secretor mothers, maternal baseline 25OHD was associated with sialyl-lacto-N-tetraose (LSTb; p=0.0350) and the change in maternal 25(OH)D between 1 and 4 months was associated with lacto-N-tetraose (LNT; p=0.0265).

Conclusion(s):

Maternal vitD status appears to have an impact on the HMO profile of human milk, with the greatest changes noted on the HMO profile of non-secretor compared to secretor mothers.