====== GLP-1 Receptor (Glucagon-Like Peptide-1 Receptor) ======

The **GLP-1 receptor** is a G protein–coupled receptor (GPCR) primarily expressed on pancreatic beta cells, but also found in the brain, heart, gastrointestinal tract, and kidneys.

===== Physiological Role =====

GLP-1 receptors are activated by **glucagon-like peptide-1 (GLP-1)**, an incretin hormone secreted by the intestinal L-cells in response to food intake.

=== Key Actions ===
  * Stimulates insulin secretion (glucose-dependent)
  * Inhibits glucagon release
  * Delays gastric emptying
  * Reduces appetite via central nervous system pathways
  * Enhances beta-cell survival and function

===== Therapeutic Relevance =====

==== GLP-1 Receptor Agonists (GLP-1 RAs) ====

Synthetic agents that mimic the action of endogenous GLP-1 by binding and activating the GLP-1 receptor. Common drugs include:
  * **Semaglutide** (Ozempic®, Wegovy®)
  * **Liraglutide** (Victoza®, Saxenda®)
  * **Dulaglutide** (Trulicity®)
  * **Exenatide** (Byetta®, Bydureon®)

=== Clinical Uses ===
  * Type 2 Diabetes Mellitus
  * Obesity and weight management
  * Cardiovascular risk reduction (certain agents)
  * Investigational uses: Alzheimer’s disease, Idiopathic Intracranial Hypertension (IIH), Parkinson’s disease

===== Central Nervous System Effects =====

GLP-1 receptors in the brain (especially hypothalamus and brainstem) influence:
  * Satiety and food intake regulation
  * Reward and addiction circuits
  * Neuroinflammation and neurodegenerative processes

===== References =====
  * Nauck MA, Meier JJ. "Incretin hormones: Their role in health and disease." Diabetes Obes Metab. 2018.
  * Drucker DJ. "Mechanisms of Action and Therapeutic Application of GLP-1." Cell Metab. 2018.