Tolerance develops toward GLP-1 receptor agonists' glucose-lowering effect in mice

Area of Science:

• Pharmacology
• Endocrinology
• Diabetes Research

Background:

• Glucagon-like peptide 1 (GLP-1) receptor agonists are widely used antidiabetic medications.
• These drugs effectively lower blood glucose and pose a low risk of hypoglycemia.
• Previous research suggests tolerance may develop to certain GLP-1 receptor agonist effects, like gastric motility, in both animals and humans.

Purpose of the Study:

• To formally investigate whether tolerance develops to the glucose-lowering effects of GLP-1 receptor agonists in mice.
• To test the hypothesis of tolerance development in a murine model.

Main Methods:

• The direct glucose-lowering efficacy of GLP-1 receptor agonists was assessed in non-fasted mice.
• Intraperitoneal glucose tolerance tests were employed to measure glucose-lowering effects.
• Two specific agonists, exenatide and liraglutide, were administered over an 18-day treatment period.

Main Results:

• Both exenatide and liraglutide demonstrated a significant loss of efficacy over the 18-day treatment period.
• The observed diminished efficacy was compared to the acute effects of the drugs.
• Results indicate a substantial reduction in the glucose-lowering capacity of these agonists with repeated administration.

Conclusions:

• The study concludes that tolerance develops to the glucose-lowering effects of GLP-1 receptor agonists in mice.
• These findings highlight a potential limitation in the long-term efficacy of these antidiabetic drugs in this model.
• Further research may be warranted to explore the mechanisms and implications of this tolerance.