title: Maternal breast milk transforming growth factor-beta and feeding intolerance in preterm infants.
abstract: BACKGROUND
  Feeding intolerance (FI) occurs commonly in the neonatal intensive care unit. Breast milk contains a large pool of transforming growth factor-beta (TGF-β). Few studies describe TGF-β levels in preterm milk, and the relationship to FI remains unexplored. We measured TGF-β levels in preterm breast milk to investigate a correlation with FI in preterm infants.
  
  
  METHODS
  Prospective observational trial of 100 mother-infant pairs, enrolling infants born below 32 wk gestation and less than 1,500 g, and mothers who planned to provide breast milk. TGF-β levels were measured using enzyme-linked immunosorbent assay. Infant charts were reviewed for outcomes.
  
  
  RESULTS
  TGF-β declined postnatally, most elevated in colostrum (P < 0.01). TGF-β2 levels were higher than TGF-β1 at all time points (P < 0.01). Colostrum TGF-β levels correlated inversely with birth weight (P < 0.01) and gestational age (P < 0.05). One-week TGF-β2 levels were reduced in growth-restricted infants with FI (P < 0.01). Of infants with necrotizing enterocolitis (NEC), TGF-β2 levels appeared to be low, but small sample size precluded meaningful statistical comparisons.
  
  
  CONCLUSIONS
  TGF-β levels decline temporally in preterm milk. TGF-β1 colostrum levels correlate inversely with birth weight and gestational age. TGF-β2 may play a role in FI in growth-restricted infants. The relationship of TGF-β2 and NEC merits future investigation.
authors.affiliation: 1] Department of Pediatrics, NorthShore University HealthSystem, Evanston, Illinois [2] University of Chicago Pritzker School of Medicine, Chicago, Illinois.
authors.forename: Brandy L
authors.initials: BL
authors.lastname: Frost
authors.affiliation: 1] Department of Pediatrics, NorthShore University HealthSystem, Evanston, Illinois [2] Department of Pediatrics, University of Alabama-Birmingham School of Medicine, Birmingham, Alabama.
authors.forename: Tamas
authors.initials: T
authors.lastname: Jilling
authors.affiliation: Research Institute, NorthShore University HealthSystem, Evanston, Illinois.
authors.forename: Brittany
authors.initials: B
authors.lastname: Lapin
authors.affiliation: Department of Pediatrics, University of Illinois at Chicago, Chicago, Illinois.
authors.forename: Akhil
authors.identifier: 0000000315027663
authors.initials: A
authors.lastname: Maheshwari
authors.affiliation: 1] Department of Pediatrics, NorthShore University HealthSystem, Evanston, Illinois [2] University of Chicago Pritzker School of Medicine, Chicago, Illinois.
authors.forename: Michael S
authors.initials: MS
authors.lastname: Caplan
mesh_terms: D004435:Eating; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D007234:Infant, Premature; D008297:Male; D008895:Milk, Human / Q000378:metabolism*; D011446:Prospective Studies; D016212:Transforming Growth Factor beta / Q000378:metabolism*
chemical_list: D016212:Transforming Growth Factor beta