Endocrine control of appetite: satiety and hunger

Question 1

Health risks of obesity

Answer 1

Heart disease
Stroke
Metabolic syndrome
Fatty liver diseases
Some cancers
Breathing problems
Osteoarthritis
Gout
Diseases of the gallbladder and pancreas
Kidney disease
Pregnancy problems
Fertility problems
Sexual function problems
Mental health problems

Question 2

Environmental/societal factors impacting obesity

Question 3

Biological factors impacting obesity

Answer 3

Many, but focus on:
Signals from the adipose tissue, pancreas, liver, and git

Question 4

nb - paper on physiology of hunger will be on canvas

Question 5

Hunger (homeostatic)

Answer 5

the physiological impulse to eat that is triggered by starvation (acute energy deprivation) in order to maintain energy balance

Question 6

Appetite

Answer 6

hedonic hunger
food intake driven by pleasure rather than by metabolic necessity

Question 7

The “thrifty genotype” hypothesis

Answer 7

Evolutionary pressure favours genes promoting weight gain, i.e. efficient storage of ingested calories when access to food is unreliable

Question 8

Blood brain barrier (BBB)

Answer 8

Made up of endothelial cells (cells that line blood cells), which are often semi-permeable but in this case are really tight <- deliberate to prevent brain infections. 2 places where the barrier is more semi-permeable: the hypothalamus and medulla oblongata

Question 9

Sagitall view

Answer 9

if the brain is cut kinda like through the nose?

Question 10

Nucleus in the context of the hypothalamus

Answer 10

really small sub areas, not a cell nucleus

Question 11

transverse view

Answer 11

cutting the brain across a horizontal plane. I’m pretty sure

Question 12

Control centre for appetite regulation

Answer 12

Hypothalamus

Question 13

Lesion

Answer 13

a region in an organ or tissue that has suffered damage through any one of a range of ways

Question 14

Paravemtricular hypothalamic nuclei (PVM)

Answer 14

Legions to this area damages satiety sensing and leads to overeating (seen in rats)

Question 15

Lateral hypothalamic nucleus

Answer 15

lesions here lead to no hunger (seen in rats)

Question 16

How is eating controlled?

Answer 16

Stomach wall stretch receptors
Glucose lipid levels detected in intestines
Stomach and gut release hormones

Question 17

Stomach wall stretch receptors

Answer 17

signal distention as food fills the stomach. = > afferents of the vagus nerve => solitary nucleus of the medulla = > hypothalamus

Question 18

Glucose lipid levels detected in intestines

Answer 18

=> sensory afferents => solitary nucleus of the medulla = > hypothalamus.

Question 19

Stomach and gut release hormones

Answer 19

CCK, Peptide YY, Glucogon-like peptide -1 (GLP-1) and ghrelin. => hypothalmus & other areas (area postrema, medulla)

Question 20

Lectin

Answer 20

Hormone makes you feel full

Question 21

Grehlin

Answer 21

Hormone that makes you feel hungry

Question 22

wtf is going on with these mice

Answer 22

THEY SURGICALLY ATTACHED THEM WTF

Question 23

Why did obese mouse attached to wild type mouse become healthy?

Answer 23

lectin began to circulate both
but also WHAT

Question 24

Where is leptin released from?

Answer 24

Adipose tissue
(Sometimes referred to as adipocytokine bc it is structurally similar to cytokines)

Question 25

High levels of leptin

Answer 25

inhibit food intake, stimulate catabloic process including loss of fat

Question 26

low levels of leptin

Answer 26

increases food intake, stimulate anabolic processes, process fat tissue builds up

Question 27

Where does leptin signal?

Answer 27

Hypothalamus -arcuate nucleus neurons Leptin stimulates neurons that expressed proopiomelanocortin (POMC) and cocaine and amphetamine-related transcript (CART) Leptin inhibits neurons that express neuropeptide Y (NPY) and agouti-related peptide (AgRP)

Question 28

Insulin is a ? term hormone

Answer 28

short

Question 29

Leptin is a ? term hormone

Answer 29

long

Question 30

Why does leptin not work for an obesity treatment?

Answer 30

Obese individuals have high levels of leptin and have developed leptin resistance

Question 31

Gut-brain signalling

Answer 31

hormones sensing the presence and absence of gut contents

Question 32

Hormones indicating the presence of food

Answer 32

CCK GIP CLP-1&2 PYY Neurotensin

Question 33

Hormones indicating the absence of food

Answer 33

Grehlin

Question 34

Where is ghrelin produced?

Answer 34

cells in the fundus of the stomach

Question 35

Acylated peptide

Answer 35

potent orexigenic activity

Question 36

Outcome of ghrelin signalling

Answer 36

increases appetite and may serve as a signal to co-ordinate nutrient acquisition with growth

Question 37

Ghrelin patterns

Answer 37

plasma levels rise 1-2 hrs before normal meals and falls to minimum 1h after eating

Question 38

How does Ghrelin stimulate food intake?

Answer 38

Reacts with its receptor in hypothalamic neurons that express NPY