OBESITY HORMONES

Question 1

PIC

Answer 1

Question 2

What hormone was discovered in 1994 that is crucial for hypothalamic regulation of appetite and body weight?

Answer 2

Leptin

Leptin is produced by adipose tissue and plays a significant role in appetite regulation.

Question 3

Which two neuron groups are found in the arcuate nucleus of the hypothalamus?

Answer 3

• Group 1: Produces agouti-related protein (AGRP) and neuropeptide Y (NPY) that stimulate feeding
• Group 2: Synthesizes pro-opiomelanocortin (POMC) leading to a-melanocyte-stimulating hormone (a-MSH) which inhibits food intake

These groups have opposing effects on appetite regulation.

Question 4

How does leptin inhibit appetite?

Answer 4

• Inhibiting AGRP neurons
• Stimulating POMC neurons

Leptin works through these mechanisms to help regulate body weight.

Question 5

Where is ghrelin produced and what is its primary function?

Answer 5

Produced by the stomach and small intestine; stimulates appetite

Ghrelin’s activity requires modification by ghrelin O-acyltransferase (GOAT).

Question 6

What modification is required for ghrelin to be active?

Answer 6

Octanoylation

This modification is carried out by ghrelin O-acyltransferase (GOAT).

Question 7

What is the predicted effect of a ghrelin receptor antagonist?

Answer 7

Inhibit appetite and cause weight loss

This approach targets appetite regulation through the ghrelin signaling pathway.

Question 8

What are GOAT inhibitors expected to do?

Answer 8

Reduce ghrelin activity, assisting in weight loss

By inhibiting GOAT, the active form of ghrelin is diminished.

Question 9

What is the predicted effect of an NPY agonist?

Answer 9

Increase appetite and cause weight gain

NPY plays a role in stimulating feeding behavior.

Question 10

What is the expected outcome of an MC4R antagonist?

Answer 10

Stimulate appetite and increase weight

MC4R is involved in the regulation of energy balance and appetite.

Question 11

Which GLP-1 receptor agonist has been approved for weight loss?

Answer 11

Liraglutide

GLP-1 receptor agonists reduce appetite and are used clinically for obesity management.

Question 12

What would a GLP-1 receptor antagonist do?

Answer 12

Increase appetite, contrary to weight loss

This reflects the role of GLP-1 in appetite suppression.

Question 13

What is the predicted effect of a leptin antagonist?

Answer 13

Reduce satiety, potentially increasing weight

Leptin normally promotes feelings of fullness, so its inhibition could lead to increased food intake.