The study, which involves researchers from Fonterra, UAE, Malaysia, and Beirut universities, was recently published in Nutrients.
Said to be the first such study involving UAE mothers, the study aimed to find out the HMOs, phospholipids (PLs), and gangliosides (GAs) concentration in transitional and mature milk.
Transitional milk is defined as breast milk produced in the first five to 15 days postpartum, while the latter refers to breast milk produced six months post-partum.
HMOs, PLs, and GAs are gaining a greater research attention as more evidence on their benefits in the growth of infants have surfaced.
HMOs have been showed to provide anti-infective protection for infants, as well as acting as immune modulators.
Forty-one Arab women were recruited from government hospitals, healthcare clinics, and mother-and-child centres in Dubai, Sharjah, and Ajman.
They found that the average HMOs concentration was higher in transitional milk than in mature milk.
For instance, average HMOs concentration in transitional milk was about 8204mg/L (± 2389 mg/L), while that of mature milk was 3905mg/L (± 1466 mg/L).
They also observed a change in the proportion of acidic HMOs and neutral HMOs in transitional and mature milk.
More acidic HMOs can be found in transitional milk (18%) as compared to mature milk (7%).
The largest decrease was seen in the acidic oligosaccharide LSTc, which dropped by 98% from 488mg/mL ± 224 mg/mL in transitional milk to 11 mg/L in mature milk.
On the other hand, the proportion of neutral HMOs was 82% in transitional milk, but higher at 93% in mature milk.
In this regard, 3FL was the only HMO to increase across this period.
“The changes in HMOs levels over the course of lactation may reflect changes in the development stages of the growing infant, and a requirement for specific compositions of these HMOs,” the researchers concluded.
Secretor Vs non-secretor milk
The researchers also noticed significant differences in the different HMOs components between secretor and non-secretor milk samples.
For example, the secretor milk samples were higher in 2’FL and lower in 3FL and 3’S3FL as compared to non-secretor milk samples.
Changes in PLs concentration
A higher PLs concentration was also found in transitional milk as compared to mature milk.
The researchers measured seven types of PLs and found that on average, transitional milk has 269mg/L (±89.2mg/L) of PLs, while that of mature milk was lower at 219.6mg/L (±85mg/L).
Significant changes in the relative distribution of PL classes were also observed, with PE increasing from 25% in transitional milk to 36% in mature milk.
Phosphatidyl choline (PC) and phosphatidyl serine (PS) decreased from 25% to 14% and 11% to 7% respectively.
“Changes in the individual PL distribution observed between early milk and mature milk may be the consequence of the changing structure.
“It is reported that colostrum and transitional milk has much larger fat droplet size than that of mature milk,” the researchers said.
Less significant changes in GAs
The difference in GAs concentration was less obvious between the two.
On average, GAs concentration was 21.18mg/L (±11.46mg/L), slightly higher than that of mature milk (20.18mg/L ±9.75mg/L).
However, the relative distribution of GAs classes, namely disialoganglioisde 3 (GD3) and monosialoganglioside 3 (GM3), changed across the two-time points from 56% and 44% in transition milk, to 9% and 91% respectively for mature milk.
In conclusion, the researchers said the study provided new information about the HMO, PL, and GA concentrations in breast milk specific to UAE mothers.
Human Milk Oligosaccharide, Phospholipid, and Ganglioside Concentrations in Breast Milk from United Arab Emirates Mothers: Results from the MISC Cohort
Authors: Paul McJarrow, et al