Lecture A9

Question 1

physiological characteristics of adipocytes

Answer 1

-insulin sensitive
-lipid storage of TAG
-secretion of endocrine hormones

Question 2

adipocytes are insulin sensitive to control ______

Answer 2

energy production and storage

Question 3

TAG stands for _____

Answer 3

triacylglycerol

Question 4

adipocytes are what type of cell?

Answer 4

fat cells

Question 5

adipocytes maintain homeostasis between ____

Answer 5

lipolysis and lipogenesis

Question 6

Three types of adipocytes

Answer 6

-white adipocyte
-brown adipocyte
-beige adipocyte

Question 7

both white and brown adipocyte differentiation share _____

Answer 7

key features

Question 8

master adipogenic regulator example

Answer 8

-peroxisome proliferator-activated receptor-y (PPAR-y)

Question 9

adipogenic stimuli activates what?

Answer 9

-signaling pathways that coordinate TF and promote SC commitment to adipogenic fate

Question 10

commitment to and stability of adipocyte differentiation requires _____

Answer 10

extensive epigenomic modifications

Question 11

adipocyte generation (general)

Answer 11

fibroblastlike precursor cell –> adipocyte precursor cell accumulates lipid droplets –> fat cell

Question 12

adipocyte proliferation is regulated by ____ (3)

Answer 12

dietary, micro-environmental and hormonal cues

Question 13

New adipocytes are formed via the _____ and ___ of resident ______

Answer 13

-proliferation
-differentiation
-adipocyte precursor cells

Question 14

adipocytes are formed and enlarge as needed for _____

Answer 14

story of excess dietary energy

Question 15

Obesity (def.)

Answer 15

the excessive accumulation of body fat

Question 16

obesity is a consequence of

Answer 16

-persistent energy intake that exceeds energy expenditure

Question 17

obesity leads to the ____ and ____ of adipocytes

Answer 17

-hyperplasia
-hypertrophy

Question 18

Hyperplasia (def.)

Answer 18

increase in number

Question 19

Hypertrophy (def.)

Answer 19

increase in size

Question 20

Hyperplasia of adipocytes involves ______

Answer 20

commitment and differentiation of stem cells/preadipocytes (vascular stroma)

Question 21

Adipocytes can also dedifferentiate when? and redifferentiate when? in mothers.

Answer 21

1)pregnancy
2) Lactation & Involution (uterus shrink in size)

Question 22

When pregnant, adipocytes start to _____

Answer 22

de-differentiate (become pre-adipocytes)

Question 23

When lactating, adipocytes are now mostly _____ and start to _____

Answer 23

-pre-adipocytes
-re-diiferentiate

Question 24

most common fat cell is ____

Answer 24

white adipocytes

Question 25

white adipocyte function?

Answer 25

used to store energy in the form of fat

Question 26

white adipocytes are found where? (7)

Answer 26

-subcutaneous (under skin) -intra-abdominal -epicardial (in the heart) -gonadol -gluteal -bone marrow -intramuscular

Question 27

white adipocyte morphology

Answer 27

spherical

Question 28

white adipocyte cell composition (4)

Answer 28

-single lipid droplet -few mitochondria -flattened peripheral nucleus -little endoplasmic reticulum

Question 29

brown adipocyte function?

Answer 29

converts chemical energy to heat to protect against cold weather without shivering (non-shivering thermogenesis)

Question 30

brown adipocyte are found where? (5)

Answer 30

-interscapular -paravertebral -perirenal -cervical -supraclavicular

Question 31

brown adipocyte morphology

Answer 31

-elliptical (oval) -smaller than white adipocyte

Question 32

brown adipocyte cell composition (3)

Answer 32

-multiple small lipid droplets -large number of mitochondria -oval central nucleus

Question 33

beige adipocyte (def.)

Answer 33

immature cell in white fat tissue that matures to burn fat

Question 34

beige adipocyte function

Answer 34

thermogenic potential

Question 35

beige adipocyte localization

Answer 35

-found in white adipose tissue with appropriate stimuli

Question 36

beige adipocyte morphology

Answer 36

spherical

Question 37

beige adipocyte cell composition

Answer 37

-mitochondria appear after stimulation -uniocular morphology but small lipid droplets after stimulation

Question 38

WAT stands for _____

Answer 38

white adipose tissue

Question 39

BAT stands for _____

Answer 39

brown adipose tissue

Question 40

types of WAT

Answer 40

-visceral WAT -subcutaneous WAT

Question 41

visceral WAT examples

Answer 41

-perirenal -retroperitoneal -omental -mesentric

Question 42

subcutaneous WAT examples

Answer 42

-abdominal -gluteal -femoral

Question 43

visceral WAT function

Answer 43

-energy storage and various adipokine secretion

Question 44

visceral WAT is correlated with ____

Answer 44

-high incidence of metabolic disorders

Question 45

subcutaneous WAT function

Answer 45

-insulating layer, energy storage and various adipokine secretion

Question 46

subcutaneous WAT is correlated with ____

Answer 46

-low incidence of metabolic disorders

Question 47

breakdown of fat and release of free fatty acids into bloodstream from adipocytes is stimulated by ______

Answer 47

nerves releasing norepinephrine

Question 48

cLD stands for ___

Answer 48

central lipid droplet

Question 49

LDM stands for ____

Answer 49

lipid droplets

Question 50

regulation of lipolysis and thermogenesis in brown adipocytes pathway

Answer 50

1) B3-AR (receptor) is activated by noradrenaline which causes release of cAMP 2)cAMP activates PKA (protein kinase A) 3) PKA activates HSL (hormone-sensitive lipase), ATGL (Adipose triglyceride lipase) and perilipins on the surface of lipid droplets 4)lipases break down lipid droplets to make free-fatty acids (FFA) 5) FFA enters mitochondria to be broken down to make heat

Question 51

Perilipins reside on ____ and regulate _____

Answer 51

-surface of lipid droplets -lipases

Question 52

Adipocytes can be formed from two different lineages: _______

Answer 52

-resident mesenchymal cells in the stromal-vascular fraction of adipose tissue -hematopoietic progenitors that reside in bone marrow

Question 53

mesenchymal precursors + MYF5 TF = ____

Answer 53

BAT adipocyte precursor

Question 54

mesenchymal precursors + (no MYF5 TF) = ____

Answer 54

WAT adipocyte precursor

Question 55

WAT adipocyte precursor forms ____

Answer 55

white adipocyte, beige adipocyte

Question 56

BAT adipocyte precursor forms ____

Answer 56

-brown adipocyte

Question 57

endothelial precursor forms this adipocyte?

Answer 57

white & brown adipocyte

Question 58

muscle satellite cell forms this adipocyte?

Answer 58

brown adipocyte

Question 59

MYF5 transcription factor also acts as _____

Answer 59

muscle regulatory factor (MRF)

Question 60

mesenchymal stem cells that form (pre-)adipocytes don't receive ______

Answer 60

WNT signals

Question 61

pre-adipocytes that form adipocytes don't receive _____

Answer 61

WNT signals

Question 62

adipogenic stimuli activates _____ which activates _______ which _____

Answer 62

-C/EBPδ/β -PPARγ & C/EBPa -turns on adipocyte genes

Question 63

PPARγ stands for ______

Answer 63

-Peroxisome proliferator -activatedreceptor

Question 64

PPARγ is a ______. It is highly expressed in ______

Answer 64

-nuclear receptor with fatty acids as their activating cofactor -adipose tissues

Question 65

“Master regulator” of adipogenesis is _____

Answer 65

PPARγ

Question 66

C/EBPδ/β stands for ______

Answer 66

CCAAT-enhancer-binding protein

Question 67

C/EBPδ/β is a ______

Answer 67

bZip protein

Question 68

C/EBPδ/β is at the crossroads between ______

Answer 68

proliferation and differentiation

Question 69

early adipogenesis has these TF: _____

Answer 69

C/EBPδ C/EBPβ

Question 70

mature adipocyte has these TF: _____

Answer 70

C/EBPa C/EBPβ PPARγ

Question 71

genes activate in early adipogenesis has this element: _____

Answer 71

C/EBP-Response Element

Question 72

PRDM16 (PR/SET Domain 16) function

Answer 72

transcription factor that promotes formation of brown adipocytes

Question 73

brown adipocyte precursors

Answer 73

-myf-5 precursor (muscle precursor) -pre-adipocyte

Question 74

PR domain of PRDM16 contains ______

Answer 74

- a ZNF-C2H2 – Zinc Finger DNA binding domain

Question 75

Suppressing PRDM16 in brown adipose cells causes them to______

Answer 75

- change into myocytes

Question 76

Genes like _____ encode proteins that are needed in BAT cells

Answer 76

Ucp1, Cidea and Elovl3