Biological activity of AC3174, a peptide analog of exendin-4.
Exenatide, the active ingredient of BYETTA (exenatide injection), is an incretin mimetic that has been developed for the treatment of patients with type 2 diabetes. Exenatide binds to and activates the known GLP-1 receptor with a potency comparable to that of the mammalian incretin GLP-1(7-36), thereby acting as a glucoregulatory agent. AC3174 is an analog of exenatide with leucine substituted for methionine at position 14, [Leu(14)]exendin-4. The purpose of these studies was to evaluate the glucoregulatory activity and pharmacokinetics of AC3174. In RINm5f cell membranes, the potency of AC3174 for the displacement of [(125)I]GLP-1 and activation of adenylate cyclase was similar to that of exenatide and GLP-1. In vivo, AC3174, administered as a single IP injection, significantly decreased plasma glucose concentration and glucose excursion following the administration of an oral glucose challenge in both non-diabetic (C57BL/6) and diabetic db/db mice (P<0.05 vs. vehicle-treated). The magnitude of glucose lowering of AC3174 was comparable to exenatide. The ED(50) values of AC3174 for glucose lowering (60 minute post-dose) were 1.2 microg/kg in db/db mice and 1.3 microg/kg in C57BL/6 mice. AC3174 has insulinotropic activity in vivo. Administration of AC3174 resulted in a 4-fold increase in insulin concentrations in normal mice following an IP glucose challenge. AC3174 was also shown to inhibit food intake and decrease gastric emptying in rodent models. AC3174 was stable in human plasma (>90% of parent peptide was present after 5 h of incubation). In rats, the in vivo half-life of AC3174 was 42-43 min following SC administration. In summary, AC3174 is an analog of exenatide that binds to the GLP-1 receptor in vitro and shares many of the biological and glucoregulatory activities of exenatide and GLP-1 in vivo.
Hargrove
Diane M
DM
Amylin Pharmaceuticals Inc. 9360 Towne Centre Drive, San Diego, CA 92121, United States. diane.hargrove@amylin.com
Kendall
Eric S
ES
Reynolds
James M
JM
Lwin
Aung N
AN
Herich
John P
JP
Smith
Pamela A
PA
Gedulin
Bronislava R
BR
Flanagan
Shawn D
SD
Jodka
Carolyn M
CM
Hoyt
Julie A
JA
McCowen
Kevin M
KM
Parkes
David G
DG
Anderson
Christen M
CM
D000262:Adenylyl Cyclases / Q000378:metabolism; D000818:Animals; D001786:Blood Glucose / Q000032:analysis; D045744:Cell Line, Tumor; D002462:Cell Membrane / Q000378:metabolism; D003924:Diabetes Mellitus, Type 2 / Q000097:blood*; D004355:Drug Stability; D004435:Eating / Q000187:drug effects; D004789:Enzyme Activation / Q000187:drug effects; D000077270:Exenatide; D005746:Gastric Emptying / Q000187:drug effects; D052216:Glucagon-Like Peptide 1 / Q000378:metabolism; D005947:Glucose / Q000378:metabolism; D005951:Glucose Tolerance Test; D006207:Half-Life; D006801:Humans; D007004:Hypoglycemic Agents / Q000008:administration & dosage / Q000097:blood* / Q000737:chemistry / Q000378:metabolism / Q000493:pharmacokinetics* / Q000494:pharmacology; D007274:Injections, Intraperitoneal; D007279:Injections, Subcutaneous; D007328:Insulin / Q000097:blood; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008817:Mice, Mutant Strains; D010455:Peptides / Q000008:administration & dosage / Q000097:blood* / Q000737:chemistry / Q000378:metabolism / Q000493:pharmacokinetics* / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley; D014688:Venoms / Q000008:administration & dosage / Q000097:blood* / Q000737:chemistry / Q000378:metabolism / Q000493:pharmacokinetics* / Q000494:pharmacology
D001786:Blood Glucose; D007004:Hypoglycemic Agents; D007328:Insulin; D010455:Peptides; D014688:Venoms; D052216:Glucagon-Like Peptide 1; D000077270:Exenatide; D000262:Adenylyl Cyclases; D005947:Glucose