lifestyle, aging and disease Flashcards
1
Q
How does genetic variation influence how we age
A
- genetic variation in ‘longevity’ genes may influence lifespan
- single nucleotide polymorphisms (SNPs) are most frequent source of polymorphic changes
- EX: higher IL-6 related to lower lifespan, polymorphism in promoter region of IL-6 increases its expression
2
Q
How is mitochondrial damage related to aging?
A
- mitochondria contains genes
- accumulating mutations in mitochondrial DNA accelerates aging, errors in replication become more frequent with againg
- damage to mitochondrial genome occurs 10x more frequent than nuclear genome (due to generation of reactive oxygen species)
3
Q
What are reactive oxygen species?
A
- superoxide anion, hydrogen peroxide, hydroxyl radical
- if they get out mitochondria can damage DNA, proteins
4
Q
How are mouse models used for testing mitochondrial mutations?
A
- mutation to DNA polymerase
- replicates DNA as cells divide but also corrects errors
- shows accelerated signs of againg if it cannot correct errors
- drops in brain wave, heart inlargement
5
Q
Can exercise reduce effects of aging?
A
- used mutated mouse model
- when exercised prevents damage from reactive oxygen species,
6
Q
How is caloric restriction related to aging?
A
- restriction of 20-40% restriction
- severe food restriction extended healthy lifespan of rats
- also seen in other snimals but no conclusive evidence in humans
7
Q
How may the insulin signalling pathway be relevant to aging
A
- pathway to phosphorylate receptor, turn on receptor substrate, causing glut 4 to move to mem….
- conserved over wide range of species (other species have pretty much same pathway)
- want to be sensitive to insulin (not chronically stimulating the pathway)
- pathway effects FOXO1 (activated by CR and resveratrol at high dosage)
- promotes expression on longevity genes and puts break on pro aging genes
- caloric restriction activates FOXO1
8
Q
How is aging and disease related?
A
- inc life expectancy has caused increase in age related disease
9
Q
How is exercise related to disease
A
- risk of death in breast cancer is 3 times higher in love vs high fitness groups
- inverse correlation between physical fitness and risk of colon cancer
- aerobic exercise improves cognitive function in older adults and aids in memory (can slightly increase brain volume in elderly)
10
Q
Type 2 diabetes
A
- studied diabetes prone subjects over 4 years
- recommended 150min per week of moderate exercise, encouraged to follow food pyramid, goal to lose 8% of initial body weight
- those who changed their lifestyle vs metformin vs placebo, showed lower incidence of diabetes if changed lifestyle
11
Q
What can resveratrol do?
A
mimic effects of caloric restricaiton in worms, yeast and flies
12
Q
Does insulin signalling pathway lead to activation of longevity genes
A
INSULIN SIGNALLING DOES NOT ACTIVATE LONGEVITY GENES
