Physiology of appetite and weight

Question 1

Food intake should = what?

Answer 1

Energy expenditure

Question 2

What is the average amount of calories needed per day?

Answer 2

Women - 2000
Men - 2500

Question 3

How many calories per gram are in carbs, fat and proteins?

Answer 3

Question 4

What are the parameters for BMI?

Answer 4

Question 5

What is a more accurate parameter for healthily weight in asians?

Answer 5

Waist circumference

Question 6

What are the hunger hormones in the stomach called?

Answer 6

Ghrelin

Question 7

What is the name of the axis in the GI tract that generates neuronal and hormonal signals of hunger?

Answer 7

Gut-brain axis

Question 8

What are the satiety hormones?

Answer 8

Peptide YY in gut
Cholecystokinin
Leptin in fat tissues

Question 9

Where is the feeding centre in the brain?

Answer 9

In the lateral nuclei of the hypothalamus

Question 10

Where is the satiety centre in the brain?

Answer 10

Ventromedial nuclei of the hypothalamus

Question 11

Lesions in which parts of the hypothalamus can affect appetite and feeding?

Answer 11

Paraventricular nuclei
Dorsomedial nuclei
Arcuate nuclei

Question 12

What does anorexigenic mean?

Answer 12

Something that causes a loss of appetite

Question 13

What does orexigenic mean?

Answer 13

Something that causes an increase in appetite

Question 14

Which molecules can decrease feeding (anorexigenic)?

Answer 14

Question 15

Which molecules can increase feeding (orexigenic)?

Answer 15

Question 16

How does Ghrelin affect appetite?

Answer 16

Ghrelin interacts with AGRP neurons –> produce agouti related protein and neuropeptide Y.
AGRP stimulation increases food intake.

Question 17

How is POMC involved in appetite?

Answer 17

Insulin/Leptin/CCK interact with POMC neurons. POMC produces a-MSH (Melanocyte stimulating hormone) and cocaine and amphetamine-regulating transcript (CART).
POMC stimulation decreases food intake.

Question 18

How does a-MSH affect appetite regulation?

Answer 18

a-MSH (Melanocyte stimulating hormone) stimulates neuronal melanocortin receptors (MCR-3 and MCR-4) which then increases energy expenditure.

Question 19

How does AGRP affect appetite regulation?

Answer 19

AGPR is an antagonist to MCR-4. MCR-4 is stimulated by a-MSH and increases energy expenditure.
AGRP prevents this increase in energy expenditure.

Question 20

Which hormones can block AGPR?

Answer 20

Insulin
Leptin
CCK

Question 21

Which neuronal mutations have been linked to obesity in children?

Answer 21

POMC
MCR-4

Question 22

What affects satiety?

Answer 22

Meal quality
Meal quantity
Nutritional status
Energy balance

Question 23

Where is leptin produced and expressed?

Answer 23

Produced in adipose cells
Expressed in white adipose tissue

Question 24

What is the function of leptin?

Answer 24

Regulates energy homeostasis - provides energy storage signal to hypothalamus.
Neuroendocrine functions, metabolism and immune functions

Question 25

A deficiency of leptin in mice led to what?

Answer 25

obesity

Question 26

Does increased amounts of adipose tissue produce more of less leptin?

Answer 26

More

Question 27

What effect does leptin receptor stimulation have on fat?

Answer 27

It decreases fat storage.

Question 28

Which factors override the effect of increased adipose leptin in the regulation of food intake?

Answer 28

Society and culture

Question 29

Above which BMI is someone considered morbidly obese?

Answer 29

>40

Question 30

Which genetic syndromes are associated with obesity?

Answer 30

Prader-Willi Bardet-Biedl

Question 31

Which neuroendocrine disorders can cause obesity?

Answer 31

Hypothalamic lesions Cushing's syndrome Hypothyroidism

Question 32

How much weight should those with obesity aim to lose?

Answer 32

10% 0.5-1kg per week

Question 33

What is the MOA of lipase inhibitors?

Answer 33

Inhibits lipases in the lumen of the gut. It prevents the hydrolysis of dietary fat inso absorbable FFAs/glycerol.

Question 34

What are the adverse effects of lipase inhibitors?

Answer 34

Flatulence, oily faecal leakage, diarrhoea. Reduction in the absorption of fat soluble vitamins - ADEK

Question 35

Which drug is a lipase inhibitor?

Answer 35

Orlistat

Question 36

What is the MOA of GLP-1 agonists?

Answer 36

Stimulates POMC to reduce hunger, energy intake and food cravings. Inhibits AGRP to increase satiety.

Question 37

What are the side effects of GLP-1 agonists?

Answer 37

Pancreatitis

Question 38

What is an example of GLP-1 agonists?

Answer 38

Liraglutide Semaglutide

Question 39

What are the pharmacological treatments for obesity?

Answer 39

Lipase inhibitors GLP-1 agonists

Question 40

What are the different tiers of weight management?

Answer 40

Tier 1 - Universal services Tier 2 - Lifestyle management Tier 3 - Specialist management. Assessment for surgery, medications. Tier 4 - Pre-op assessment

Question 41

What are the advantages to bariatric surgery?

Answer 41

25-20% weight loss Life-long treatment cost savings Improve co-morbidities