Lipoprotein and apolipoprotein secretion by a newborn piglet intestinal cell line (IPEC-1)

Ruben Gonzalez-Vallina, Heng Wang, Reggie Zhan, Helen M. Berschneider, Robert M. Lee, Nicholas O. Davidson, Dennis D. Black

Research output: Contribution to journalArticlepeer-review

72 Scopus citations

Abstract

The aim of these studies was to characterize the synthesis and secretion of lipoproteins and apolipoprotein B (apo B) and apo A-I by a newborn swine intestinal epithelial cell line (IPEC-1). Differentiated cells exhibited enterocytic features, including microvilli. [:3Hloleic acid was taken up and incorporated into cellular lipids and secreted into the basolateral medium in lipoproteins. Total apo B and apo A-I secreted increased with oleic acid incubation. However, cellular apo B and apo A-I content did not change. Whereas undifferentiated cells synthesized and secreted only apo B-100, both apo B-100 and apo B-48 were produced by differentiated cells. The ratio of radiolabeled apo B-48 to ape B-100 in both basolateral medium and cell homogenate increased with oleic acid treatment after 24-h steady-state labeling. However, apo B mRNA editing was unchanged, indicating posttranslational regulation of this ratio. Pulse-chase radiolabeling demonstrated no major changes in cellular or basolateral medium apolipoprotein labeling kinetics with oleic acid or dexamethasone incubation. The dissociation of apo B and apo A-I mass secretion from the secretion of radiolabeled apo B and apo A-I in response to oleic acid absorption suggests the presence of an intracellular pool of apolipoprotein with a slow turnover that is mobilized for secretion in response to fatty acid uptake.

Original languageEnglish
Pages (from-to)G249-G259
JournalAmerican Journal of Physiology - Gastrointestinal and Liver Physiology
Volume271
Issue number2 34-2
DOIs
StatePublished - Aug 1996

Keywords

  • fatty acid
  • immunoprecipitation
  • messenger ribonucleic acid editing
  • radiolabeling
  • triglyceride

Fingerprint

Dive into the research topics of 'Lipoprotein and apolipoprotein secretion by a newborn piglet intestinal cell line (IPEC-1)'. Together they form a unique fingerprint.

Cite this