Obesity and Meta Syndrome

Question 1

where are the hunger and satiety centres

Answer 1

hypothalamus

Question 2

where from the body do you get the don’t eat signals

Answer 2

circulating hormones and gut signals

Question 3

what is the structure and role of ghrelin

Answer 3

28 aa peptide from neuroendorcrone cells in the stomach

released when stomach is empty - powerful hypothalamic orexigenic agent - ie makes you hungry

Question 4

what is an anorexigenic and what are some examples

Answer 4

suppress hunger 
CCK insulin 
GLP-1 
peptide yy 
somatostatin 
oxyntomodulin

Question 5

what is the role of leptin

Answer 5

long term alteration of food intake and energy exposure - comes from adipocytes

Question 6

what pathway do anorexigens reach the brain

Answer 6

via the nucleus of the solitary tract in the medulla

Question 7

the arcuate nucleus in the hypothalamus sends projections to…

Answer 7

satiety centre in the ventromedial nucleus

hunger centre in the later hypothalamic area

Question 8

what two types of neurones are present in the arcuate nucleus

Answer 8

anorexigenic

orexigenic

Question 9

what do anorexigenic neurones secrete

Answer 9

proopiomelanocortin (POMC) and cocaine amphetamine related trasncript (CART)

Question 10

what do oreigenic neurones secrete

Answer 10

agouti-related peptide (AGRP) and neuropeptide Y

Question 11

what does AGRP inhibit

Answer 11

melanocortin receptors

Question 12

what physiological consequences occur do to extreme starvation

Answer 12

muscle wasting 
fatigue
diminished respiratory capacity 
slowed heart rate 
loss of heat generation 
apathy 
death from respiratory or cardiac failure or infection

Question 13

describe what anorexia nervosa is

Answer 13

body weight more than 15% below standard ie BMI less than 17.5
voluntary weight loss
distorted body image
amenorrhoea in women

Question 14

what are the life treating association with anorexia nervosa

Answer 14

2-5% suicide risk or die of starvation

Question 15

what is bulimia nervosa

Answer 15

without low body weight but similar to anorexia - common in american college girls

Question 16

what are the classes of BMI

Answer 16

underweight less than 18.5
normal 18.5-24.99
overweight 25-25.99
obese more than 30

Question 17

what is a high BMI more commonly associated with

Answer 17

type 2 diabetes

Question 18

what is a very small fraction of obesity caused by

Answer 18

genetic defects altering leptin and ghrelin

Question 19

what are some of the physiological consequences of obesity

Answer 19

osteoarthritis 
hypertension/DVT
T2 diabetes 
cancers 
erectile dysfunction and female infertility 
sleep apnoea 
NAFLD
stress, low self esteem etc

Question 20

what must you have a combination of to have metabolic syndrome

Answer 20

3 out of 5 of 
obesity 
T2 DM 
hypertension 
High plasma triglycerides 
low HDL cholesterol

Question 21

what causes the lipid overflow ectopic fat model

Answer 21

positive energy balance from low exercise and high fat diet

can lead to good fat ( subcutaneous) but also to visceral fat which alters FFA metabolism and release of adipokines

Question 22

what is a hyperlipolytic state

Answer 22

high amount of visceral fat which produces more non-esterified fatty acids (NEFA)
in turn makes you less sensitive to insulin and impairs insulin release from B cells

Question 23

what does high insulin resistance causes

Answer 23

high plasma insulin and higher plasma glucose which induce an inflammatory response and production of ROS

Question 24

a combination of dyslipidaemia and ROS is thought to underly which conditions

Answer 24

atheroma and CVD