Lecture 30 - ageing

Question 1

The two theories of ageing?

Answer 1

Programmatic - we are programed to die (genetic programming)

• higher metabolic rate - shorter life - we have a lower metabolic rate and live longer
• ageing in evolutionary and selection terms
• gradual loss of system function
• metabolic rate and life span correlate well
• age dependent decline in thymus dependent system

Stochastic - ageing is caused by environemtnal damage

• free radical theory - oxidative metabolism produces free oxygen radicals can damage cells, not as many protective mechanims
• less collagen, glycogen ec.t
• callorie restriction
• doesnt show any effect taking vit E, C compared to not taking it
• in humans - no evidence that calorie restriction works

Question 2

change in physiological funcitons

Answer 2

• decrease muslce function

- decreas renal function (creatine clearance)

Question 3

change in physiological functions

Answer 3

• decrease muscle function

- decrease renal function (creatine clearance)

Question 4

Some disease can decrease time till death

Answer 4

e.g atherosclerosis

• increased neoplasms with increase age
• diseases - more serious consequences with age- accidents, resp infections

Question 5

extraceullular matrix and ageing

Answer 5

collagen - becomes cross linekd with age, reduced flexibility of tisses
-elastin - loss of this