Endocrine Regulation of Energy

Question 1

What is the function of brown adipose tissue?

Answer 1

1. The transfer of food into heat energy 2. Lipid utilisation

Question 2

What is the function of white adipose tissue?

Answer 2

1. Fuel storage 2. Insulation 3. Produces the hormone leptin

Question 3

Where is the hormone leptin produced?

Answer 3

White adipose tissue

Question 4

What receptor does leptin act on?

Answer 4

ObRb receptor

Question 5

What does leptin do?

Answer 5

Decreases food intake Increases energy expenditure

Question 6

What can a mutation of the Ob gene lead to and why?

Answer 6

Obesity as the Ob gene is responsible for leptin production

Question 7

Where is ghrelin produced?

Answer 7

PD1 cells in the fundus of the stomach

Question 8

What does ghrelin do?

Answer 8

Stimulates appetite Increases food intake Promotes fat storage

Question 9

What is meant by orexigenic?

Answer 9

Increased hunger and food intake

Question 10

Where does ghrelin act?

Answer 10

GHS-R receptor in the brain

Question 11

What is meant by anorexigenic?

Answer 11

Decreased hunger and food intake

Question 12

What role does alpha-MSH play in obesity?

Answer 12

Melanocortins are anorexigenic thus reducing food intake, fighting obesity.

Question 13

What role does MC4 play?

Answer 13

MC4 is an agonist to alpha-MSH, thus aiding decrease in food intake and obesity

Question 14

What is hyperphagia

Answer 14

Eating a lot of food

Question 15

What are the uses of leptin, and what are it’s limits?

Answer 15

Leptin can be administered to treat obesity. - Decreases appetite and fat mass - Causes hyperinsulinaemia However obesity is multifactorial and so leptin is not a perfect solution.

Question 16

What are the effects of GLP-1?

Answer 16

Increases insulin production Decreases glucagon production Slows gastric emptying, reducing food intake.

Question 17

Obesity is…

Answer 17

BMI over 30

Question 18

Consequences of obesity

Answer 18

Question 19

How does obesity lead to diabetes?

Answer 19

Amyloid and fat deposits in pancreas lead to decreased insulin production.

Insulin resistance is also made worse by obesity and physical inactivity.

Question 20

Stimulation of NPY Y5 receptors has what effect on the body?

Answer 20

Stimulates food intake.

Question 21

What role does AGRP play in obesity?

Answer 21

Causes obesity by:

1. Inhibiting MC4 receptors
2. Stimulating NPY Y5 receptors

Question 22

Prader-Willi Syndrome

Answer 22

Description. Prader-Willi syndrome is a complex genetic condition that affects many parts of the body. In infancy, this condition is characterized by weak muscle tone (hypotonia), feeding difficulties, poor growth, and delayed development.

• Imprinting defect on Chr 15
• Small hands and feet
• Hypotonic infants
• Feed poorly until 2 years, then ravenous appetite
• Learning difficulties

Question 23

Weight management approach:

Answer 23

1. Dietary change – Energy restriction
2. Physical activity – Increase energy expenditure
3. Behavioural change/psychological support – Underpins and enables the first two

Question 24

Orlisat does what?

Answer 24

Gastrointestinal lipase inhibitor to reduce weight gain.

Question 25

Naltrexone/bupropion function:

Answer 25

Increases in POMC signaling reduces food intake and leads to weight loss.

Question 26

Surgical obesity options

Answer 26