TERM TEST 2 Flashcards
______ - Laying awake but resting, stress free in the morning after sleep, not digesting food and in the absence of thermoregulatory heat production
BMR : Basal metabolic rate
_______ - similar to BMR but not measures in the morning after sleep
RMR: resting metabolic rate
_______ - metabolic rate in various conditions that cause the rate to fall below BMR
MMR: Minimal metabolic rate
_________ - Total daily energy expenditure (TDEE) is higher than BMR due to energy requirements of feeding, cold exposure and muscle use
FMR: Field metabolic rate
_____ - maximal steady state metabolic rate during hard exercise
MaxMR: Maximal Metabolic Rate
What is the major neuroendocrine efferent pathways implicated in body-weight Homeostasis ?
SNS; Sympathetic Nervous System
mice over expressing human uncoupling protein-3 in skeletal muscle are
hyperphagic & lean
skeletal muscle respiratory uncoupling prevents
diet induced obesity + insulin resistance in mice
promoting inefficient metabolism in muscle represent
a potential treatment for obesity and its complications
mice lacking mitochondrial uncoupling protein are
cold sensitive but not obese
UCP-1 is _______ the only system involved in thermogenesis even within BAT
not the only system…
for two adults of similar size their TDEE can very by as much as _______ and is determined by what factor?
1500 kcal/day
how active their lifetsyle is
what are the major organs that contribute most to whole body BMR
- liver
- gastrointestinal
- kidney
- lung
- heart
- brain
- skeletal muscle
which major organ that contributes to whole body BMR is most metabolically active in comparison to skeletal muscle
liver
protein synthesis contributes to what major organ that contributes to whole body BMR
gastrointestinal tract
increased neuron activity with increases ATP release contributes to what major organ that contributes to whole body BMR
brain
_______ organ contributes to whole body BMR vi Ca2+ ATPase and Actomyosin ATPase
heart
what is the percentage of TEF for TDEE
8-12%
what is the percentage of Physical activity for TDEE
both exercise + NEAT
15-30%
(it can be >/= 50% in highly active individuals)
what is the percentage of BMR for TDEE
60-70%
within BMR’s 60-70% of TDEE what are the names contributing to that %
20% _______
25-35% ______
19-28% ______
13-30% ________
4-8% ______
7-10% ______
3% _______
2-8 % ______
- mitochondrial leak
- protein synthesis
- Na+/K+ ATPase
- Other; Nucleic Acid synthesis
- Ca2+ ATPase
- gluconeogenesis
- ureagenesis
- actomyosin ATPase
the thermic affect of feeding typically stimulates metabolic rate by ~ ___ with a peak stimulation _______ in humans
25%
1-2hrs after a meal
explain Obligatory vs Facultative in terms of TEF
OBLIGATORY
~35-45%
- metablism of ingested aa in liver for glucose, fat, urea, and protein synthesis
OBLIGATORY
~25-30%
- swallowing, digestion, and absorption of food, enzyme secretion
FACULTATIVE
~30-40%
- SNS activation
_______ directly activates the SNS which _______ metabolic rate and _______ feeding
POMC neurons
increase metabolic rate and decrease feeding
what are the two possible roles of the SNS
- thermogenesis
- lipolysis
explain the overview of control of BAT (brown adipose tissue)
- PVN activation
- SNS releases NE
- beta adrenergic receptor on BAT and increase cAMP
- cAMP activates PKA
- PKA activates lipolytic enzymes (Perylipin, HSL)
- lypolysis which releases FFA fromTG
- FFA for thermogenesis + activator of UCP-1
how critical is UCP-1
without UCP-1 (GMO animals to knockout UCP-1) you would expect?
- lipolysis still present
- no increase in O2 consumption
- no activation of UCP-1
- low brown adipocytes compared to wild animals
how critical is UCP-1
In wild animals what happens
- induces lipolysis
- activates UCP-1
- huge increase in O2 consumption
- increased brown adipocytes
thermogenesis is due to activation of _____ through lipolysis
UCP-1
______ Blocks lipolysis
perilipin
what are the two pathways of FFA?
- beta oxidation (crebs cycle)
+
citric acid cycle - binds to UCP1
_____ stimulation increases release of FA
adrenergic stimulation
regulation of adrenergic stimulation
- basal:
- stimulated
- CGI-58 + PLIN1 are bound together which indicates rest by keeping lipase enzymes inactive
- CGI-58 + PLIN1 are NOT bound together due to PKA. PKA phosphorylated and activate lipase enzymes causing the release of 3 FA per enzyme
thermogenesis in BAT at a given moment is determined by the
the deg of activation (can be alter in seconds)
capacity of thermogenesis is determined by the
deg of recruitment of tissue (can alter in days/weeks)
mice over expressing UCP-3 are
- hyperphagic
- lean
(at more, weighed less)
mice lacking UCP-1 =
- protected from obesity
- not obese
- cold sensitive = active BAT
mice w/out BAT ______
develop obesity
why is UCP-1 not the only system w/ thermogenesis
because mice lacking UCP-1 were not obese rather they were protected from it
skeletal muscle respiratory uncoupling prevents
- diet induced obesity
- insulin resistance
______ = potential treatment for obesity + its complications
promoting inefficient metabolism
~_____% = whole body daily expenditure (muscle Ca2+ cycling)
what is adaptive thermogenesis
- responds to temp + diet
- occurs in BAT mitochondria
- variable
- reg by brain
activation of adaptive thermogenesis in BAT =
more cells
more UCP1
larger energy expenditure
SARCOLIPIN:
- Alabation =
decreased energy required for Ca2+ transport
______ trumps beta adrenergic receptor signalling for favoured muscle-based diet induced thermogenesis
sarcolipin
SARCOLIPIN:
increase heat production via
Ca2+ - ATPase pump
______ regulator of muscle based thermogenesis
sarcolipin
______ uncpouples hydrolysis of ATP from accumulation of Ca2+ By SERCA pumps
SARCOLIPIN
SARCOLIPIN:
- inhibits _____
- doesn’t affect ____
- Ca2+ uptake _____ as ______ increases
ca2+ transport
ATPase activity
decreases as sarcolipin
what are the 3 characteristics of sarcolipin null mice
increase Ca2+ transport
increase muscle relaxation
increase Ca2+: ATP ratio (in resting physiological conditions)
characteristics of E1 W/ out sarcolipin
- Ca2+ face cytosol
- high infinity of Ca2+
- cytosol gate open
- lumen gate closed
characteristics of E2 w/out sarcolipin
- Ca2+ face lumen
- low infinity of Ca2+
- cytosol gate closed
- lumen gate open
- Ca2+ detaches and enters lumen
characteristics of E1 w/ sarcolipin
- needs more Ca2+ cause SLN blocks its binding site
characteristics of E2 w/ sarcolipin
- sarcolipin causes slippage
- Ca2+ slips off before
cytosol gate can close - uncoupling ratio altered
- Ca2+ doesnt enter lumen
____ decreases efficiency of SERCA
sarcolipin
if sarcolipin decreases efficiency of SERCA what does this mean for ATP cost
ATP cost increases to maintain CA2+ homeostasis
if sarcolipin decreases efficiency of SERCA why does VO2 not change the SERCA efficiency ?
similar VO2 + BODY WEIGHT found in chow fed (low fat diet) WT + SLN-KO
describe everything about SLN-KO mice after consuming a high fat diet
and propranolol enhances which *
- increased weight*
- increased adiposity
- increased obesity (diet)*
- > glucose intolerance
- decreased food intake
- similar activity level
- > decreased EE
- decreased adaptive
thermogenesis - decreased whole body VO2
- better exercise* performance
- increased SNS activation
- decreased muscle VO2 via Beta blocker
how does SLN-KO mice have better exercise performance
decreased VO2= Decreased energy = decreased efficiency = better performance
no SLN can result in
increased SNS activity
increased resting muscle metabolism
_______ = primary + more effective mediator
SLN
failure to activate SLN in response to overfeeding may predispose individuals to ?
- metabolic syndrome
- T2D
- CVD
due to chronic SNS activation
what are some common things found with DHA supplementation
decreased SERCA Ca2+ transport efficiency
increased RMR
increased energy expenditure
_______
-used from combating obesity
- increase EE through effects on Ca2+ cycling
DHA
_________ directly stimulates EE in skeletal muscle
leptin
