PCSK9 is expressed in pancreatic delta-cells and does not alter insulin secretion.
Biochem Biophys Res Commun
; 390(4): 1288-93, 2009 Dec 25.
Article
in En
| MEDLINE
| ID: mdl-19878649
ABSTRACT
PCSK9 (Proprotein Convertase Subtilisin Kexin type 9) is a proprotein convertase that plays a key role in cholesterol homeostasis by decreasing hepatic low-density lipoprotein receptor (LDLR) protein expression. Here, we investigated the expression and the function of PCSK9 in pancreatic islets. Immunohistochemistry analysis showed that PCSK9 co-localized specifically with somatostatin in human pancreatic delta-cells, with no expression in alpha- and beta-cells. PCSK9 seems not to be secreted by mouse isolated islets maintained in culture. Pcsk9-deficiency led to a 200% increase in LDLR protein content in mouse isolated islets, mainly in beta-cells. Conversely, incubation of islets with recombinant PCSK9 almost abolished LDLR expression. However, Pcsk9-deficiency did not alter cholesterol content nor glucose-stimulated insulin secretion in mouse islets. Finally, invivo glucose tolerance was similar in Pcsk9(+/+) and Pcsk9(-/-) mice under basal conditions and following streptozotocin treatment. These results suggest, at least in mice, that PCSK9 does not alter insulin secretion.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Serine Endopeptidases
/
Somatostatin-Secreting Cells
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Insulin-Secreting Cells
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Insulin
Limits:
Animals
/
Humans
Language:
En
Journal:
Biochem Biophys Res Commun
Year:
2009
Document type:
Article
Affiliation country:
France