Please use this identifier to cite or link to this item:
Title: Bismuth ions inhibit the biological activity of non-amidated gastrins in vivo.
Austin Authors: Kovac, Suzana;Loh, Su-Wen;Lachal, Shamilah;Shulkes, Arthur;Baldwin, Graham S
Affiliation: The University of Melbourne Department of Surgery, Austin Health, Heidelberg, Victoria, Australia
Issue Date: 8-Dec-2011
Publication information: Biochemical Pharmacology 2011; 83(4): 524-30
Abstract: The peptide hormone gastrin binds two ferric ions with high affinity, and iron binding is essential for the biological activity of non-amidated gastrins in vitro and in vivo. Bi3+ ions also bind to glycine-extended gastrin17 (Ggly), but inhibit Ggly-induced cell proliferation and migration in gastrointestinal cell lines in vitro. The aims of the present study were firstly, to establish the mechanism by which Bi3+ ions inhibit the binding of Fe3+ ions to Ggly, and secondly, to test the effect of Bi3+ ions on the activity of non-amidated gastrins in vivo. The interaction between Bi3+ ions, Fe3+ ions and Ggly was investigated by ultraviolet spectroscopy. The effect of Bi3+ ions on colorectal mucosal proliferation was measured in three animal models. In vitro in the presence of Bi3+ ions the affinity of Fe3+ ions for Ggly was substantially reduced; the data was better fitted by a mixed, rather than a competitive, inhibition model. In rats treated with Ggly alone proliferation in the rectal mucosa was increased by 318%, but was reduced to control values (p < 0.001) in animals receiving oral bismuth plus Ggly. Proliferation in the colonic mucosa of mice overexpressing Ggly or progastrin was significantly greater than in wild-type mice, but was no greater than control (p < 0.01) in animals receiving oral bismuth. Thus a reduction in the binding of Fe3+ ions to Ggly and progastrin in the presence of Bi3+ ions is a likely explanation for the ability of oral bismuth to block the biological activity of non-amidated gastrins in vivo.
Gov't Doc #: 22172990
DOI: 10.1016/j.bcp.2011.11.030
Journal: Biochemical pharmacology
Type: Journal Article
Subjects: Animals
Gastrins.antagonists & inhibitors.genetics.metabolism
Ki-67 Antigen.metabolism
Mice, Transgenic
Organometallic Compounds.pharmacology
Protein Binding
Rats, Sprague-Dawley
Appears in Collections:Journal articles

Show full item record

Page view(s)

checked on Jan 27, 2023

Google ScholarTM


Items in AHRO are protected by copyright, with all rights reserved, unless otherwise indicated.