mechanisms 2 Flashcards
what is catabolism
large to small
what is anabolism
small to big
3 macronutrients
carbs
protein
fats
2 micronutrients
vitamins
minerals
what are nutrient sensing pathways
growth and development needs nutrients
pathways monitor and respond to nutrient availability in the environment
nutrients used to generate energy and building blocks of cells
what is the AMPK pathway and how does it work
AMP-activated kinase pathway
nutrient sensing pathway - senses energy balance (AMP or ADP to ATP), relays to mitochondria
if energy lvls dec, AMPK activates pathways to generate ATP and inhibit ones that consume it - inc catabolic switches off anabolic
what is GCN2 pathway and how does it work
general amino acid control non-depressible 2
nutrient sensing pathways
senses uncharged tNRAs that accumulate upon amino acid deprivation
attentuates translation, which consumes amino acids and is energy demanding (terminates this basically)
what is TOR/mTOR and how does it work
target of rapamycin
mechanistic target of rapamycin
nutrient sensing pathway
many inputs including AMPK (energy) and GCN2 (amino acids)
most attention on nutrients and growth factors
mitochondria and ROS
mit. produce ROS
these have key role in inflammation, metabolism, etc
if accumulate, can be hella bad
counteracted by antioxidants
antioxidant strategies - 3
SOD in mitochondria
gluthione peroxidase
catalase in peroxisomes
what is SOD in mitochondria and how worky
antioxidant
converts O2+ to H2O2
what is gluthione peroxidase and how worky
antioxidant
converts +OH to H2O2 and then to water and oxygen
what is catalase and how worky
antioxidant
in peroxisomes, convert H2O2 to water and oxygen
migranes and mitochondria
brain energy deficits in people with migranes
suggests energy metabolism impairment
inc energy intake by hyperexcitable brain or dec energy supply due to mitochondrial impairment
causes of oxidative stress
alcohol
diet
smoking
medication and treatments
air and water pollutants
stress
lack of good nutrition
lack or excess exercise
effects of oxidative stress
dna damage
lipid peroxidation
mitochondrial dysfunction and apoptosis
extracellular matrix depletion
fucked inflammation
alterations in nucleus structure
mitochondria and ageing effects
inc in free radicals released from mito
damaged cell, damaged mitochondria
reduced ATP production
changes neutrient sensing pathways
cellular senesence
what is cell senescence
normal cell, wont divide itself / cell cycle arrest
in response to environmental signals intrinstic or extrinsic
dynamic process, remain viable but undergo changes to metabolic activity and gene expression - to senensence associated secretory phenotype
upreg of anti apoptotic pathways, compromise repair and regen, accelerates ageing effects
what are the intrinsic and extrinsic factors that drive a cell to senescence
dna damage
reactive metabolites
oncogenes
inflammation
how is cell senesence good - 3
for embryonic development
wound healing and regen
tumour suppression
how is cell senesence meh
reprograms il-6
how is cell senesence bad - 1
tumour development, stem cell exhaustion
what is the senesence associated secretory phenotype and what does it cause
pro inflammatory, tissue destructive
contributes to inflammation, metabolic dysreg, stem cell dysfunction, ageing phenotypes, chronic disease, geriatric syndromes, loss of resilience
what does SASP acc do
inc cytokines, chemokines, growth factors
ROS
bioactive lipid metabolites
proteases
microRNA, DNA fragments, nucleic acids
what is trained immunity
cells of our innate immune system can be trained to respond to one exposure to make a diff response on a subsequent exposure
e.g. beta glucan, BCG, diet (oxidised LDLs)
changes monocytes and macrophages in particular - inc response to second threat vs first
western diet and trained immunity
triggers systemic inflammation, augmenting cellular responses
epigenetic effect on cells e.g. due to inc oxidised LDLs in diet
inc trained immunity
what is a microbiome
microbial community that occupies well defined habitat and has distinct properties - microorganisms and theater of activity/ host tissues
what is a microbiota
commmunity of microorganisms that occupy a particular site/ habitat
what is dysbiosis
imbalances in microbial communities in or on body. associated with many diseases
