Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
34
pubmed:dateCreated
2003-8-18
pubmed:abstractText
The present study provides a new understanding about the mechanisms involved in cholesterol absorption by the intestinal cells. Contrary to general belief, our data show that newly absorbed cholesterol is neither immediately available for secretion with apoB lipoproteins nor exclusively secreted as part of chylomicrons. Based on our data, cholesterol transport by enterocytes can be broadly classified into two independently modulated, apoB-dependent and -independent, pathways. Cholesterol secretion by the apoB-dependent pathway is induced by oleic acid, is repressed by microsomal triglyceride transfer protein inhibitors, and occurs only with larger apoB-containing lipoproteins. ApoB-independent pathways do not require microsomal triglyceride transfer protein and involve efflux mediated by ABCA1, high density lipoprotein assembly, and possibly other unknown mechanisms. There are at least two different metabolic pools of cholesterol. The newly absorbed and pre-absorbed cholesterol are preferentially secreted via apoB-independent and apoB-dependent pathways, respectively. In contrast to compartmentalization for secretion, these two metabolic pools are equally accessible for cellular esterification. The esterified cholesterol is mainly secreted by the apoB-dependent pathway, whereas both the pathways are involved in the secretion of free cholesterol. Thus, enterocytes transport exogenous cholesterol by several independently regulated pathways raising the possibility that targeting of apoB-independent pathways may result in selective inhibition of cholesterol transport without affecting triglyceride transport.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
22
pubmed:volume
278
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
31610-20
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
2003
pubmed:articleTitle
Multiple, independently regulated pathways of cholesterol transport across the intestinal epithelial cells.
pubmed:affiliation
Department of Anatomy and Cell Biology, State University of New York Downstate Medical Center, Brooklyn, New York 11203, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't