CPPS303 XIAO Lecture 8 Gut Hormones March_26_2025 (1) Flashcards
(24 cards)
What is the role of GLP-1 in glucose metabolism?
GLP-1 regulates glucose metabolism by enhancing glucose-stimulated insulin secretion and improving insulin sensitivity.
GLP-1 also promotes β cell proliferation and survival.
What are the actions of GLP-1 on multiple organs?
GLP-1 targets multiple organs, improving glucose control, enhancing insulin secretion, and promoting β cell proliferation.
Actions include effects on liver, fat, and muscle.
What is the significance of incretin in diabetes therapy?
Incretin and incretin-based therapies are used for type 2 diabetes management by enhancing insulin secretion and lowering blood glucose levels.
These include GLP-1 receptor agonists and DPP-4 inhibitors.
What is the half-life of GLP-1?
The half-life of GLP-1 is approximately 2 minutes.
This rapid degradation is due to the action of Dipeptidyl peptidase-4 (DPP-4).
What effect does DPP-4 inhibition have on GLP-1?
Inhibition of DPP-4 prevents GLP-1 degradation, thereby enhancing its incretin action.
This increases insulin secretion and improves glycemic control.
What is GIP and its function?
GIP (gastric inhibitory polypeptide) enhances glucose-stimulated insulin secretion in response to glucose or fat ingestion.
It is released from K-cells of the small intestine.
True or False: GLP-1 receptors are expressed on hepatocytes.
False.
GLP-1 receptors are not expressed on hepatocytes.
List the major roles of GLP-1.
- Enhances insulin secretion in a glucose-dependent manner
- Delays gastric emptying
- Increases satiety
- Improves glycemic control
- Aids in weight loss
- Provides cardioprotection
What is the role of GLP-2?
GLP-2 is involved in intestinal growth, nutrient absorption, and maintenance of intestinal health.
It also promotes intestinal blood flow and inflammation control.
Fill in the blank: The enzyme that rapidly converts GLP-1 to its inactive metabolite is called _______.
Dipeptidyl peptidase-4 (DPP-4)
What is the effect of GLP-1 on appetite?
GLP-1 decreases appetite and promotes satiety.
This is beneficial for weight management in obesity.
What is the relationship between GLP-1 and β cell mass?
GLP-1 promotes β cell proliferation and decreases apoptosis, thereby expanding β cell mass.
This is linked to transactivation of the epidermal growth factor receptor (EGFR).
What is the function of DPP-4 in relation to GLP-1 and GIP?
DPP-4 cleaves GLP-1 and GIP, affecting their bioactivity and contributing to their metabolic effects.
This enzymatic action limits the duration of incretin action.
How does GLP-1 receptor activation affect glucagon secretion?
GLP-1 receptor activation decreases glucagon secretion.
This helps to lower blood glucose levels.
What is Teduglutide?
Teduglutide is a GLP-2 analogue approved for the treatment of short bowel syndrome.
It enhances intestinal absorption and growth.
Describe the mechanism by which GLP-1 contributes to weight loss.
GLP-1 contributes to weight loss by delaying gastric emptying, increasing satiety, and improving glycemic control.
These actions collectively reduce food intake.
What is the impact of GLP-1 on chylomicron synthesis?
GLP-1 inhibits chylomicron synthesis and secretion, thereby affecting lipid metabolism.
This is important for managing lipid levels in the body.
What contributes to cardioprotection?
Secretion
Secretion is a vital process involved in various physiological functions, including cardioprotection.
Is there a GLP-1 receptor on enterocytes?
No
GLP-1 receptors are not found on enterocytes, indicating a specific regulatory pathway.
What does GLP-2 promote indirectly?
Dietary lipid absorption and chylomicron secretion
This process occurs via CD36 glycosylation and nitric oxide.
What type of chylomicron release does GLP-2 promote?
Stored chylomicron release
GLP-2 promotes the release of stored chylomicrons rather than their biosynthesis.
Where is GLP-2 receptor expression found?
On myofibroblast, enteric neurons, and vagal afferent neurons
This expression indicates a role in neural regulation of gut lipids.
What is a summary of GLP-1’s regulation?
GLP-1 regulation of glucose metabolism
GLP-1 has multiple functions related to glucose metabolism.
What are the functions of GLP-1 and GLP-2?
Regulation of lipids
Both GLP-1 and GLP-2 play significant roles in lipid regulation.
