ageing and disease

Question 1

mutations in which genes have been associated with familial Alzheimer’s disease?

Answer 1

Presenilin 1.

A gamma secretase 1 component that generates amyloid beta from the amyloid precursor protein.

Question 2

what is apolipoprotein E? (APOE)

Answer 2

a fat-binding protein that transports cholesterol to neurons

Question 3

what is clusterin (CLU)?

Answer 3

a chaperone, so promotes proper protein folding

Question 4

what is TREM2 (triggering receptor expressed on myeloid 2)?

Answer 4

myeloid immunoglobulin receptor that promotes inflammation

Question 5

what is microtubule associated protein Tau (MAPT)?

Answer 5

protein maintains microtubule stability in astrocytes and oligodendrocytes, but can aggregate to form neurofibrillary tangles

Question 6

proto-oncogenes are most likely to encode what type of cellular component?

Answer 6

signal transduction proteins.

the proto-oncogens are those that have the potential to up regulate cell growth and differentiation. As most mechanisms that regulate these processes involve signalling pathways, most proto-oncogenes are signal transduction proteins.

Question 7

Immortalisation is one of the key hallmarks of cancer. Which one of the following is believed to be a key cause of immortalisation of cancer cells in many tumours?

Answer 7

reactivation of telomerase enzyme?

Telomeres are usually shortened with every cell division, which places a limitation on cell lifespan. Depleted telomeres results in apoptosis. Telomerase is an enzyme that is capable of extending telomeres.

Question 8

what enzyme is capable of extending telomeres?

Answer 8

telomerase

Question 9

what cells are responsible in the formation of bone matrix?

Answer 9

osteoblasts

Question 10

cyte vs blast

Answer 10

cyte= mature cell
blast= immature cell

Question 11

chondro vs osteo

Answer 11

chondro= of the carilage
osteo= of the bones

Question 12

what is loss of skeletal muscle mass and function with age known as?

Answer 12

sacropenia.

sacro=muscle
penia= lacking

Question 13

osteopenia vs osteoporosis vs osteoarthritis

Answer 13

osteopenia; lack of bone mass
osteoporosis; causes production of weaker bones
osteoarthritis; arthritis of bones

Question 14

There are many risk factors for developing type 2 diabetes mellitus. What is an example of a NON-modifiable risk factor for this disease?

Answer 14

ethnicity

Question 15

Many people diagnosed with type 2 diabetes mellitus actually produce sufficient quantities of insulin. The cause of hyperglycaemia in these people can be caused by what?

Answer 15

insulin resistance

• insulin promotes absorption of glucose into the liver, fat and skeletal muscle cells to maintain normal glycose levels in the blood. Failure to response to insulin results in elevates glucose levels in the bloodstream (hyperglycaemia).

Question 16

when can a definite diagnosis of alzheimer’s disease be made?

Answer 16

after death?

Dementia is a symptom that can be caused by a number of neurodegenerative disease, which includes Alzheimer’s. Only examination of the patients brain to confirm presence of amyloid beta plaques and neurofibrillary tangles can confirm the diagnoses.

Question 17

what is the greatest risk factor for Alzheimer’s disease?

Answer 17

increased age

Question 18

Menopause is a normal part of ageing. discuss.

Answer 18

hormone replacement therapy replaces the oestrogen that the body naturally loses, which can alleviate many of the symptoms associates with menopause.
the loss of healthy primordial follicles means that the body stops producing oestrogen which causes levels of FSH and LH to increase, as well as weight gain.

Question 19

what affect does menopause have on levels of FSH and LH?

Answer 19

increase.

the loss of healthy primordial follicles means that the body stops producing oestrogen, which causes levels of FSH and LH to increase, as well as weight gain

Question 20

how aging contributes to the development of diseases such as diabetes, cancer, and dementia.

Answer 20

diabetes;
insulin resistance: as people age, their cells become less responsive to insulin (insulin resistance; can lead to high blood sugar levels (hyperglycaemia) and eventually type-2 diabetes.
pancreatic function decline: ageing can impair the function of beta cells in the pancreas which are responsible for producing insulin, this exacerbates the body’s inability to regulate blood glucose levels.
chronic inflammation:

cancer:
accumulation of DNA damage
immune system decline
cellular senescence (cells stop dividing but do not die)
epigenetic changes (alteration in the epigenome- chemical tags on DNA- can activate oncogenes/science tumour suppressor gene)

dementia
neurodegeneration (progressive loss of neurons and synaptic connections)
protein misfolding (proteins like beta-amyloid and tau)
oxidative stress (accumulation of reactive oxygen species, ROS, damages neurone)
vascular changes

telomere shortening; protective caps on ends of chromosomes shorten with each cell division, when telomeres become too short cells can enter senescence/apoptosis, contributing to ageing and disease development