Biological activity of a new pegylated form of an of glucagon-like peptide-1 (GLP-1) analogue pegGLP-1 was studied in C57Bl/6 mice under normal conditions and during modeling of streptozotocin-induced type I diabetes mellitus. pegGLP-1 differs from GLP-1 (7-37) by polyethylene glycol residue covalently bound to His7, Lys26, and Lys34 of the GLP-1 molecule. It was shown that single intragastrical administration of pegGLP-1 induced an increase in GLP-1 level in blood serum of healthy mice. The maximum level of this parameter was observed in 4-8 h. pegGLP-1 elimination half-time was 8.5 h and mean retention time was 15 h. Administration of pegGLP-1 to animals with modeled type I diabetes mellitus was followed by an increase in the levels of GLP-1 and insulin in blood serum, produced a hypoglycemic effect, and improved the parameters of glucose-tolerance test. Biological activity of pegGLP-1 was higher than activity of GLP-1.
Keywords: glucagon-like peptide; hyperglycemia; insulin; pegylated glucagon-like peptide analogue; streptozotocin-induced diabetes mellitus.