Enterocyte and M-cell transport of native and heat-denatured bovine beta-lactoglobulin: significance of heat denaturation.
The three-dimensional structure, digestibility, and immunological properties of bovine beta-lactoglobulin (beta-lg) are modified by heat treatments used in processing of liquid milk products. Because it is not known if such treatments also modify the intestinal transport properties of beta-lg, the transport of native and heat-denatured bovine beta-lg was investigated in experimental cell models using Caco-2 cells and M cells. Transport of beta-lg labeled with a fluorescent marker was followed with fluorometric measurements, electrophoretic analyses, and fluorescence microscopy. The data show that both cell types transported native beta-lg more efficiently than they did heat-denatured beta-lg. In addition, M cells transported native beta-lg more than Caco-2 cells. Transport of native and heat-denatured beta-lg was transcellular. The electrophoretic data also suggest that heat-denatured beta-lg may have degraded more than native beta-lg during the transport.
Rytkönen
Jani
J
Biotechnology Laboratory, Kajaani University Consortium, University of Oulu, Sotkamo, Finland. jani.rytkonen@oulu.fi
Valkonen
Kaija H
KH
Virtanen
Vesa
V
Foxwell
Ruth A
RA
Kyd
Jennelle M
JM
Cripps
Allan W
AW
Karttunen
Tuomo J
TJ
D000818:Animals; D001692:Biological Transport; D018938:Caco-2 Cells; D002417:Cattle; D002460:Cell Line; D020895:Enterocytes / Q000378:metabolism*; D004847:Epithelial Cells / Q000378:metabolism*; D006358:Hot Temperature; D006801:Humans; D007782:Lactoglobulins / Q000737:chemistry* / Q000378:metabolism*; D011489:Protein Denaturation; D014357:Trypsin / Q000378:metabolism
D007782:Lactoglobulins; D014357:Trypsin