cancer/sarcopenia Flashcards
Symptoms of cancer
- fatigue
- lump under skin
- weight changes
- skin changes
- changes in bowel
- difficulty swallowing
- persistant pain, fevers
- unexplained bleeding/bruising
causes of cancer (3 paths)
Proto-oncogenes- involved in normal cell growth and division. however when these genes are mutated they become cancer causing genes (oncogenes) allowing cells to grow/divide when they shouldnt
Tumor suppressor- involved in controlling cell growth and division. Cells w alterations in tumor suppressor genes may divide in uncontrolled manner
DNA repair genes- involved in fixing damaged DNA. cells w mutations in these genes tend to develop additional mutations
4 Stages of cancer
- smaller than 2cm, localized
- 2-5cm, becomes vascularized
- > 5cm, spreads to lymph nodes
- Metastasized, defragments into vasculature
How does dysfunctional adipose tissue afffect tumor development (3 ways)
- inflamation
- adipose tussue recruits m1 macrophages (proinflammatory)
- increased expression of C reactive pro, IL6, TNFa - Insulin resistance
- chronic hyperinsulinaemia - Hypoxia angiogenesis
- angiogenesis (helps get tumor vascularized)
what is cachaxia
80% of cancer patients will have it
characterized by increased protein degradation and decreased pro synthesis
Cachaxia flow
Tumor-> TNFa/ IL6 (systematic inflamation)–> muscle wasting, increase brown fat (for nothing), fat depletion, Increases UCP1 (ruins gradient leads to less energy)
Exercise effect on tumor
increase AMPK activation in tumor
inhibits AKT/MTOR pathway in tumor which inhibits its growth
first line of defence in imune function
NK cells and T cells (tumors inhibit these)
How does exercise help with immune function
exercise increases epinephrine which releases NK cells
exercise induced IL6 is involved w NK cell distribution
What is sarcopenia characterized by
loss of strength, coordination, mobility, decreased resting energy expenditure, increase risk of falls
Aging + sarcopenia flow chart
Aging–> decrease PA –> increase abdominal fat –> decrease adiponectin, increase TNFa, increase IL6–> muscle wating and macrophage recruitment (inflamation)
3 general aspects of sarcopenia
- muscle fibre atrophy
- loss of muscle fibres (greater loss of type 2, fewer MUs)
- slowing of contractile properties
SMAD3 path
Smad 3 results in calcium mishandling which increases calpain which targets actin and myosin
how mitochondrial dysfunction affects muscles
Increase ROS-> increase ER stress -> blocks mTOR
increase AMP/ATP–> increase AMPK-> blocks mTOR
What does IGF stim
stims both proliferation and differentiaction of sat cells during muscle growt
-induces calcineruon nuclear factor which actibates GATA2 (related to hypertrophy)