Ageing Flashcards
What is the maximum human life?
90-122 years (despite disease management).
What age group is most vulnerable to disease?
Old people.
Whats the difference between ageing and disease?
1). Ageing
- normal.
- universal.
- inevitable.
- irreversible.
2). Disease
- not normal.
- not universal.
- not inevitable.
- often reversible.
What are the 4 theories of ageing?
1) . Evolutionary.
2) . Cellular.
3) . Molecular.
4) . System.
What theory explains the evolutionary significance of ageing?
Disposable Soma Theory.
What is the evolutionary theory?
- Distinction between maintenance of the body (soma) and maintenance of the reproduction system.
- Animals of high risk dont maintain their soma (body), but invest time in reproduction, therefore, less likely to be protected.
What are some examples of the evolutionary theory?
1). Tortoise
- low risk.
- long-lived.
- reproduce more slowly.
- effective maintenance system.
2). Rat
- high risk.
- short-lived.
- reproduce quickly.
- ineffective maintenance systems.
What is the cellular theory?
- Ageing is associated with mitochondrial dysfunction.
- Results to reduced ATP production and generation of oxygen species.
- Ageing is a result of the damage from free radicals (created from electron loss).
What are free radicals?
- Oxygen electrons become lost and free radicals arise, causing ageing.
What environmental factors cause free radicals?
- Pollution.
- Radiation.
- Cigarette smoke.
What is a result of free radicals?
- DNA damage (mitochondria damage).
- Lipid and protein damage.
- Damage accumulates over time (wear and tear theory).
- Harder for body to maintain steady state (homeostasis).
What is oxidative stress?
An imbalance of the production of free radicals and antioxidants.
- Can cause intercelluar damage, physiological damage and physiological decline.
What is the role of an antioxidant?
To ‘mop up’ free radical –> present in fruit and veg.
What is a telomere?
The red bit at the end of a chromosome.
What is the role of telomeres?
To protect the chromosome from damage (protection from ageing).
What is the process of telomere shortening?
- The protective effect is lost.
- Can lead to apoptotic cell death.
What causes telomere shortening?
Exposure to oxygen free radicals.
- Oxygen free radicals can modulate the reduction of telomeres.
What is the molecular theory?
- Mutation in an inssulin pathway gene increases lifespan.
- Insulin pathway is correspondence with metabolic requirements.
Which gene involved in insulin has been found more prevalent in women than men?
FOXO3a.
- More prevalent in women aged over 92 compared with women aged 80/or less.
What is the effect of the FOXO3a gene?
May have a less risk of developing diabetes and cancer.
What are the 2 molecular theories?
1) . Gene mutations and ageing theory.
2) . Calorie restriction theory.
What is the molecular: calorie restriction theory?
- Calorie restriction slow ageing and increase life span.
- Eating too much increases ageing.
What is the effects of calorie restriction?
- Lower insulin levels.
- Lower triglyceride levels.
- Less free-radical damage.
What is the homeostatic reserve mechanisms?
Ageing results in loss of physiological reserve.
What is the process of homeostatic reserve mechanism also known as?
Homeostenosis
- leads to a higher vulnerability to disease seen with ageing.
What is homeostenosis?
- Occurs when an individual is in a ‘stressed’ state, in which they move away from homeostasis.
- This is a process of ageing.
- The person goes past the limit in which homeostasis can be restored.
