module 7- part 1 Flashcards
Adipose tissue is ____ (very, minimally) sensitive to a persons insulin sensitivity
very
does insulin resistance occur before or after obesity/hyperglycemia
- before
insulin resistant adipose tissue associated with:
a) high blood FFA, high adiponectin,
b) dec expression of key adipogenic transcription factors, high adiponectin
c) high blood FFA, low adiponectin
d) inc expression of adipogenic transcription factors, low adiponectin
c) high bl FFA, low adiponectin
t/f insulin resistant adipose tissue is associated with dec expression of key adipogenic transcription factors
true
What did a study on blood markers in T2D show?
a) t2d higher blood insulin and glucose levels
b) higher blood NEFA and TGs
c) lower blood insulin levels
d) lower NEFA and TGs
e) a &c
f) a& d
g) a&b
h) b&c
g) a&b
Where is NEFA released from? What are they bound to?
adipose tissue depots
albumin
Which of the following is NOT a possible fate of non-esterified fatty acids (NEFA) in the liver?
A) Conversion into TAG and storage in lipid droplets
B) Direct excretion into the bile without modification
C) Conversion into ketone bodies during fasting or low glucose levels
D) Oxidation to generate ATP via the citric acid cycle
E) Packages as TAG into VLDL
B
What is true about NEFA and BMI?
a) Blood NEFA levels are directly proportional to body fat mass
b) Blood NEFA is inversely proportional to BMI
c) Results were inconclusive
d) there is no correlation between BMI and NEFA
D
What is true about NEFA and insulin sensitivity?
a) directly proportional
b) inversely proportional
c) Results were inconclusive
d) there is no correlation between insulin sensitivity and NEFA
b
What is true about NEFA and HGP?
a) directly proportional
b) inversely proportional
c) Results were inconclusive
d) there is no correlation between insulin sensitivity and NEFA
a) directly proportional bc prevents insulin-suppression of glycogenolysis
How do blood NEFA levels change throughout the day?
highest in morning, drop strongly after breakfast, inc gradually during day
HSL is a critical lipase for:
a) adipose tissue glycogenesis
b) VLDL production
c) adipose tissue lipolysis
d) hepatic de novo lipogenesis
c
t/f: Obesity is associated with lower VLDL secretion
false
- most likely due to insulin resistance and bodys attempt to deal with higher NEFA
Which is true:
A) Obesity is associated with decreased VLDL secretion.
B) Obesity is associated with increased VLDL secretion.
C) Obesity prevents the liver from producing VLDL altogether.
D) After a meal, VLDL secretion should increase
E) VLDL production is directly proportional to insulin sensitivity
B
What is not true about insulin resistance
a) results in higher NEFA levels
b) insulin inhibits lipolysis by reducing PKA activity
c) insulin activates PDE
d) PDE causes an increase in cAMP levels
d ) it prevents an increase in cAMP levels
FFA and VLD: the viscous cycle
explain it
IR impairs lipolysis and esterification
body will increase lipolysis
causes FFA to travel to liver
inc TAG synthesis and VLDL production
basal adipose LPL activity continues to breakdown TAGS in VLDL but esterification of FFA into TAG in adipose is not as efficient
What happens in animals lacking HSL
reduced lipolytic activity but not totally eliminated, this suggests that other lipases exist (ATGL/MGL)
What comprises 95% of area in an adipocyte?
lipid droplet
What are lipid droplets used as?
storage vessels for excess lipid produced by DNL or consumed in diet
What hormones is lipolysis of TAG mainly regulaed by
insulin and glucagon
what happens to lipolysis with insulin resistance, why?
increased
due to reduced activation of PDE which converts cAMP into 5’AMP
T/F SNPs in the LPL gene influence enzyme activity associated with blood lipid levels changing.
true
Is LPL activity sensitive to nutritional status?
yes
mice that have access to food showed LPL activity greatest when they are most active (nocturnal eaters)
when food given to fasted mice, sharp increase
T/F low LPL activity promotes fat uptake
false, it limits fat uptake
why does LPL significantly dec during fasted state
bc body trying to access stored energy
which is true about LPL knockout mice?
a) larger in size, lighter fur colour
b) larger in size, darker in fur colour
c) smaller in size, lighter in fur colour
d) smaller in size, darker in fur colour
c) smaller in size, lighter in fur colour
Which is not a function of insulin in adipose tissue?
a) insulin causes glucose uptake by promoting GLUT4 translocation to PM
B) Stimulates lipolysis to release free fatty acids into the bloodstream
C) Induces LPL, promoting TAG breakdown for FA uptake
D) induces DGAT1
E) inhibits HSL activity preventing lipolysis
B
What are the primary depots for adipose tissue?
subcutaneous and visceral
2 ways that fat mass expands
inc fat cell volume (hypertrophy)
inc # of fat cells (hyperplasia)
What are pre-adipocytes made from? (for hyperplasia)
Stem cells
proliferation of existing pre-adipocytes
