Systemic and mucosal levels of lactoferrin in very low birth weight infants supplemented with bovine lactoferrin

摘要

Lactoferrin supplementation may help prevent infections in preterm infants, but the efficacy has varied with different doses and products. We assessed the absorption and excretion of bovine lactoferrin (bLF) in 31 infants receiving 100, 200, or 300 mg·kg~(–1)·day~(–1) of enteral bLF for 30 days. bLF and human lactoferrin (hLF) in infant saliva, blood, urine, and stool, as well as expressed (EBM) or donor breast milk (DBM) that were collected ( i ) before the treatment was initiated, ( ii ) at study day 22, and ( iii ) one week after treatment cessation, were measured using ELISA. During treatment, bLF was absorbed from the gastrointestinal tract and detected in plasma, saliva, and urine, as well as excreted in stool. Levels of bLF in the saliva and stool began to decline within 12 h after dosing, and bLF was undetectable in all samples one week after treatment. The concentrations of hLF exceeded those of bLF across sample types and time-points. Infants receiving EBM demonstrated higher levels of hLF in the saliva and stool than those receiving DBM. Neither bLF nor hLF levels varied by patient characteristics, bLF dosage, or infection status. This is the first study demonstrating bLF absorption into the bloodstream and distribution to saliva and urine in preterm infants. Future studies should further explore LF pharmacokinetics because higher and more frequent dosing may improve the clinical benefit of LF supplementation.