Stability of Human-Milk Oligosaccharide Concentrations Over 1 Week of Lactation and Over 6 Hours Following a Standard Meal

Abstract

Background Our previous studies revealed that human-milk oligosaccharides (HMOs) have health benefits for nursing infants and their concentrations change dynamically over 24 mo of lactation. Yet, the extent to which HMOs vary over the short term (days) and in response to acute factors such as maternal diet is unclear. Objective The purpose of this study was to determine the stability of HMO concentrations over 7 d and in response to a standard meal and sugar-sweetened beverage (SSB) over 6 h. Methods In this ancillary study, lactating mothers were enrolled at 6 wk postpartum. Participants received in-person instructions and materials to complete procedures at home. In the 1-wk experiment (n = 11), mothers pumped a milk sample at 07:00 h for 7 consecutive days. In the 6-h experiment (n = 35), mothers pumped a milk sample after an overnight fast at 06:00 h and then consumed a standard meal plus SSB provided by the study team. Mothers pumped a milk sample every hour for 6 consecutive hours. Samples were analyzed for the 19 most abundant HMOs. Repeated-measures ANOVA was used to test changes in HMO concentrations over time, reported as F(dftime, dferror) = F value, P value. Results Concentrations of all assayed HMOs were stable over 7 consecutive days, including, for example, the most widely studied HMOs in relation to infant health: 2′-fucosyllactose (2′FL) [F(2,17) = 0.39, P = 0.65], disialyl-lacto-N-tetraose (DSLNT) [F(4, 37) = 0.60, P = 0.66], and lacto-N-neotetraose (LNnT) [F(3, 32) = 1.5, P = 0.23]. Concentrations of all assayed HMOs were stable in response to a standard meal plus SSB. For example, fasted baseline concentrations of 2′FL, DSLNT, and LNnT were 2310 ± 1620 μg/mL, 560 ± 290 μg/mL, and 630 ± 290 μg/mL, respectively, and there were no changes in 2′FL [F(4, 119) = 1.9, P = 0.13], DSLNT [F(4, 136) = 0.39, P = 0.83], and LNnT [F(4, 120) = 0.64, P = 0.63] over 6 consecutive hours. Conclusions HMO concentrations are stable over 1 wk of lactation and are not acutely affected by a standard meal plus SSB in mothers.

Sex-dependent associations between human milk oligosaccharides and malaria outcomes in breastfeeding Ugandan children

“…HMOs by high performance liquid chromatography (HPLC) as described [7]. Human milk was spiked with raffinose as an internal standard.…”

“…A single human milk sample was collected from each mother in March 2018 and analyzed for 19 HMOs by high performance liquid chromatography (HPLC) as described [7]. Human milk was spiked with raffinose as an internal standard.…”

The effect of non-genetic determinants of human milk oligosaccharide profiles in milk of Ugandan mothers

“…HMO (the 19 well characterized and most abundant) analysis was performed at the University of California, San Diego, as previously described (13), by using HPLC after fluorescent derivatization. Raffinose was added to each milk sample as an internal standard for absolute quantification.…”

Residential green environments are associated with human milk oligosaccharide diversity and composition

“…All samples were frozen and stored at − 70 °C until analysis. High Performance Liquid Chromatography (HPLC) was used to identify HMOs in breastmilk as previously described 40,57,58 at the University of California, San Diego (methods described in detail in Berger et al 58 ). Milk samples were spiked with raffinose (a non-HMO carbohydrate) as an internal standard to allow absolute quantification.…”

“…Milk samples were spiked with raffinose (a non-HMO carbohydrate) as an internal standard to allow absolute quantification. HMOs were extracted by high-throughput solid-phase extraction, fluorescently labelled, and measured using HPLC with fluorescent detection (HPLC-FLD) 58 . Absolute concentrations for the 19 HMOs were calculated based on standard retention times and corrected for internal standard recovery.…”