Dataset Information

Preterm birth increases endogenous human milk peptide release compared to term birth

ABSTRACT: Hundreds of naturally occurring milk peptides have been found in term human milk. Whether there are differences between the levels of these peptides between term and preterm milk remains unknown. Premature milk is produced before complete maturation of the mammary gland and is under the influence of a different hormonal milieu, which could change enzymatic activity and protein expression within the mammary gland and result in an altered peptide profile. We employed nano-liquid chromatography tandem mass spectrometry to identify naturally occurring peptides in term and premature milks at multiple time-points across lactation and compare the abundances of these peptides. We found that preterm milks produced more unique peptide sequences than term milks on average (359 vs. 286). The peptides identified were searched for overlapping sequences with an in-house database of known functional peptides. Specifically, we found that both term and preterm milks contain peptides overlapping with known sequences with antimicrobial, opioid antagonist and immunomodulatory actions. We also compared the enzymes involved in degradation of both milks via bioinformatic analysis. This analysis reveals that plasmin is more active in preterm milk than term milk.

INSTRUMENT(S): 6520 Quadrupole Time-of-Flight LC/MS

ORGANISM(S): Homo Sapiens (human)

TISSUE(S): Mammary Epithelial Cell, Mammary Gland Epithelial Cell

SUBMITTER: David Dallas

LAB HEAD: David Dallas

PROVIDER: PXD001079 | Pride | 2016-07-07

REPOSITORIES: Pride

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			Action	DRS
	GPM22200000936.xml-pride.pride.mgf.gz	Mgf
	GPM22200000936.xml-pride.pride.mztab.gz	Mztab
	GPM22200000936.xml-pride.xml.gz	Xml
	GPM22200000937.xml-pride.pride.mgf.gz	Mgf
	GPM22200000937.xml-pride.pride.mztab.gz	Mztab

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Endogenous human milk peptide release is greater after preterm birth than term birth.

Dallas David C DC Smink Christina J CJ Robinson Randall C RC Tian Tian T Guerrero Andres A Parker Evan A EA Smilowitz Jennifer T JT Hettinga Kasper A KA Underwood Mark A MA Lebrilla Carlito B CB German J Bruce JB Barile Daniela D

The Journal of nutrition 20141224 3

<h4>Background</h4>Hundreds of naturally occurring milk peptides are present in term human milk. Preterm milk is produced before complete maturation of the mammary gland, which could change milk synthesis and secretion processes within the mammary gland, leading to differences in protein expression and enzymatic activity, thereby resulting in an altered peptide profile.<h4>Objective</h4>This study examined differences in peptides present between milk from women delivering at term and women deliv ...[more]

PMID: 25540406

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