title: BSSL and PLRP2: key enzymes for lipid digestion in the newborn examined using the Caco-2 cell line.
abstract: In rodents, bile salt-stimulated lipase (BSSL) and pancreatic lipase-related protein 2 (PLRP2) are the dominant lipases expressed in the exocrine pancreas in early life when milk is the main food. The aim of the present study was to evaluate whether BSSL and PLRP2 are also key enzymes in neonatal intestinal fat digestion. Using Caco-2 cells as a model for the small intestinal epithelium, purified human enzymes were incubated in the apical compartment with substrates, bile salt composition and concentrations physiologic to newborn infants. Both BSSL and PLRP2 hydrolyzed triglycerides (TG) to free FA and glycerol. Released FA were absorbed by the cells and reesterfied to TG. Together, BSSL and PLRP2 had a synergistic effect, increasing cellular uptake and reesterification 4-fold compared with the sum of each lipase alone. A synergistic effect was also observed with retinyl ester as a substrate. PLRP2 hydrolyzed cholesteryl ester but not as efficiently as BSSL, and the two had an additive rather than synergistic effect. We conclude the key enzymes in intestinal fat digestion are different in newborns than later in life. Further studies are needed to fully understand this difference and its implication for designing optimal neonatal nutrition.
authors.affiliation: Department of Clinical Sciences/Pediatrics, Umeå University, S-901 85 Umeå, Sweden.
authors.forename: Eva-Lotta
authors.initials: EL
authors.lastname: Andersson
authors.forename: Olle
authors.initials: O
authors.lastname: Hernell
authors.forename: Lars
authors.initials: L
authors.lastname: Bläckberg
authors.forename: Helen
authors.initials: H
authors.lastname: Fält
authors.forename: Susanne
authors.initials: S
authors.lastname: Lindquist
mesh_terms: D001647:Bile Acids and Salts / Q000378:metabolism; D001692:Biological Transport; D018938:Caco-2 Cells; D002784:Cholesterol / Q000378:metabolism; D004951:Esterification; D004952:Esters; D005227:Fatty Acids / Q000378:metabolism; D005989:Glycerides / Q000378:metabolism; D005990:Glycerol / Q000378:metabolism; D006801:Humans; D006868:Hydrolysis; D007231:Infant, Newborn; D007413:Intestinal Mucosa / Q000166:cytology / Q000201:enzymology / Q000378:metabolism; D008049:Lipase / Q000378:metabolism*; D050356:Lipid Metabolism
chemical_list: D001647:Bile Acids and Salts; D004952:Esters; D005227:Fatty Acids; D005989:Glycerides; D002784:Cholesterol; C054621:CEL protein, human; D008049:Lipase; C075988:pancreatic lipase related protein 2; D005990:Glycerol