Dipeptidyl peptidase-IV expression and activity in human glomerular endothelial cells.
Glucagon-like peptide-1 (GLP-1), a meal-stimulated gastrointestinal insulinotropic hormone inactivated by dipeptidyl peptidase-IV (DPP-IV), is reduced in type 2 diabetic patients. The present study shows that 2-week exposure of human glomerular endothelial cells to high glucose (22 mM) determines a highly significant increase in DPP-IV activity and mRNA expression, which cannot be entirely accounted for by hyperosmolarity. On the other hand, incubation of purified DPP-IV in a buffer solution added with high glucose does not affect enzyme activity. These results suggest that high glucose increases expression and activity of DPP-IV, possibly contributing to GLP-1 reduction in type 2 diabetic patients.
D001483:Base Sequence; D002021:Buffers; D002478:Cells, Cultured; D017931:DNA Primers; D018819:Dipeptidyl Peptidase 4 / Q000235:genetics / Q000378:metabolism*; D042783:Endothelial Cells / Q000201:enzymology; D052216:Glucagon-Like Peptide 1; D005947:Glucose / Q000008:administration & dosage; D006801:Humans; D007678:Kidney Glomerulus / Q000166:cytology / Q000201:enzymology*; D010455:Peptides / Q000037:antagonists & inhibitors; D012333:RNA, Messenger / Q000235:genetics
D002021:Buffers; D017931:DNA Primers; D010455:Peptides; D012333:RNA, Messenger; D052216:Glucagon-Like Peptide 1; D018819:Dipeptidyl Peptidase 4; D005947:Glucose