There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.

Abstract

Species-specific differences in the enzymatic inactivation of peptides is an important consideration in the evaluation of therapeutic efficacy. We demonstrate that glucagon-like peptide 2 (GLP-2), shown to be highly intestinotrophic in mice, promotes an increase in intestinal villus height but has no trophic effect on small bowel weight in rats. The reduced intestinotrophic activity of GLP-2 in rats is attributable to inactivation by the enzyme dipeptidyl peptidase IV (DPP-IV). GLP-2(1-33) was degraded to GLP-2(3-33) following incubation with human placental DPP-IV or rat serum but not by serum from DPP-IV-deficient rats. Administration of rat GLP-2 to DPP-IV-deficient rats was associated with markedly increased bioactivity of rat GLP-2 resulting in a significant increase in small bowel weight. A synthetic GLP-2 analog, r[Gly2]GLP-2, with an alanine to glycine substitution at position 2, was resistant to cleavage by both DPP-IV and rat serum in vitro. Treatment of wild-type rats with r[Gly2]GLP-2 produced a statistically significant increase in small bowel mass. DPP-IV-mediated inactivation of GLP-2 is a critical determinant of the growth factor-like properties of GLP-2.

Related collections

Most cited references 21

Record: found
Abstract: found
Article: not found

Dipeptidyl-peptidase IV hydrolyses gastric inhibitory polypeptide, glucagon-like peptide-1(7-36)amide, peptide histidine methionine and is responsible for their degradation in human serum

Wolfgang E. Schmidt, Baptist Gallwitz, Rolf Mentlein (1993)

Peptides of the glucagon/vasoactive-intestinal-peptide (VIP) peptide family share a considerable sequence similarity at their N-terminus. They either start with Tyr-Ala, His-Ala or His-Ser which might be in part potential targets for dipeptidyl-peptidase IV, a highly specialized aminopeptidase removing dipeptides only from peptides with N-terminal penultimate proline or alanine. Growth-hormone-releasing factor (1-29)amide and gastric inhibitory peptide/glucose-dependent insulinotropic peptide (GIP) with terminal Tyr-Ala as well as glucagon-like peptide-1(7-36)amide/insulinotropin [GLP-1(7-36)amide] and peptide histidine methionine (PHM) with terminal His-Ala were hydrolysed to their des-Xaa-Ala derivatives by dipeptidyl-peptidase IV purified from human placenta. VIP with terminal His-Ser was not significantly degraded by the peptidase. The kinetics of the hydrolysis of GIP, GLP-1(7-36)amide and PHM were analyzed in detail. For these peptides Km values of 4-34 microM and Vmax values of 0.6-3.8 mumol.min-1.mg protein-1 were determined for the purified peptidase which should allow their enzymic degradation also at physiological, nanomolar concentrations. When human serum was incubated with GIP or GLP-1(7-36)amide the same fragments as with the purified dipeptidyl-peptidase IV, namely the des-Xaa-Ala peptides and Tyr-Ala in the case of GIP or His-Ala in the case of GLP-1(7-36)amide, were identified as the main degradation products of these peptide hormones. Incorporation of inhibitors specific for dipeptidyl-peptidase IV, 1 mM Lys-pyrrolidide or 0.1 mM diprotin A (Ile-Pro-Ile), completely abolished the production of these fragments by serum. It is concluded that dipeptidyl-peptidase IV initiates the metabolism of GIP and GLP-1(7-36)amide in human serum. Since an intact N-terminus is obligate for the biological activity of the members of the glucagon/VIP peptide family [e. g. GIP(3-42) is known to be inactive to release insulin in the presence of glucose as does intact GIP], dipeptidyl-peptidase-IV action inactivates these peptide hormones. The relevance of this finding for their inactivation and their determination by immunoassays is discussed.

0 comments Cited 121 times – based on 0 reviews      Review now

Bookmark

Record: found
Abstract: found
Article: not found

Induction of intestinal epithelial proliferation by glucagon-like peptide 2.

S Asa, P Erlich, Daniel Drucker … (1996)

Injury, inflammation, or resection of the small intestine results in severe compromise of intestinal function. Nevertheless, therapeutic strategies for enhancing growth and repair of the intestinal mucosal epithelium are currently not available. We demonstrate that nude mice bearing subcutaneous proglucagon-producing tumors exhibit marked proliferation of the small intestinal epithelium. The factor responsible for inducing intestinal proliferation was identified as glucagon-like peptide 2 (GLP-2), a 33-aa peptide with no previously ascribed biological function. GLP-2 stimulated crypt cell proliferation and consistently induced a marked increase in bowel weight and villus growth of the jejunum and ileum that was evident within 4 days after initiation of GLP-2 administration. These observations define a novel biological role for GLP-2 as an intestinal-derived peptide stimulator of small bowel epithelial proliferation.

0 comments Cited 99 times – based on 0 reviews      Review now

Bookmark

Record: found
Abstract: found
Article: not found

Glucagon-like peptide-1-(9-36) amide is a major metabolite of glucagon-like peptide-1-(7-36) amide after in vivo administration to dogs, and it acts as an antagonist on the pancreatic receptor.

Lotte Knudsen, Lone Pridal (1996)

This study assesses the importance of metabolites formed following exogenous administration of glucagon-like peptide-1-(7-36) amide (GLP-1). After subcutaneous (s.c.) administration of GLP-1 to dogs the plasma immunoreactivity of GLP-1 measured by two different radioimmunoassays (RIAs) were higher than that measured by a sandwich enzyme-linked immunosorbent assay (ELISA). This discrepancy was due to the formation of the metabolites GLP-1-(9-36) amide, GLP-1-(7-35) and GLP-1-(7-34). Receptor binding studies using baby hamster kidney cells expressing the human pancreatic GLP-1 receptor showed that the affinity of GLP-1-(9-36) amide, GLP-1-(7-35) and GLP-1-(7-34) was 0.95%, 12% and 2.8%, respectively, of the affinity of GLP-1-(7-36) amide. Furthermore, GLP-1-(9-36) amide was shown to be an antagonist to adenylyl cyclase activity, whereas GLP-1-(7-35) and GLP-1-(7-34) were shown to be agonists. GLP-1-(9-36) amide was shown to be present in vivo in amounts up to 10-fold that of GLP-1-(7-36) amide. Due to its low binding affinity, this antagonistic metabolite does not seem to be able to cause physiological antagonism upon s.c. administration of the peptide.

0 comments Cited 37 times – based on 0 reviews      Review now

Bookmark

All references

Author and article information

Journal

PubMed ID:: 9219272

DOI:: 10.1038/nbt0797-673

ScienceOpen disciplines: Chemistry

Keywords: Animals,Biotechnology,Dipeptidyl Peptidase 4,metabolism,Glucagon,antagonists & inhibitors,pharmacology,Glucagon-Like Peptide 2,Glucagon-Like Peptides,Humans,In Vitro Techniques,Intestine, Small,drug effects,growth & development,Mice,Peptides,Protein Engineering,Rats,Rats, Inbred F344,Recombinant Proteins,genetics

Regulation of the biological activity of glucagon-like peptide 2 in vivo by dipeptidyl peptidase IV.

Read this article at

Abstract

Related collections

Drug_transporters

Most cited references 21

Dipeptidyl-peptidase IV hydrolyses gastric inhibitory polypeptide, glucagon-like peptide-1(7-36)amide, peptide histidine methionine and is responsible for their degradation in human serum

Induction of intestinal epithelial proliferation by glucagon-like peptide 2.

Glucagon-like peptide-1-(9-36) amide is a major metabolite of glucagon-like peptide-1-(7-36) amide after in vivo administration to dogs, and it acts as an antagonist on the pancreatic receptor.

Author and article information

Journal

Comments

Comment on this article

Similar content 404

Cited by 39

Most referenced authors 182