The post-maturation changes in the organism that cause loss of function.
Senescence
A clone of cells will stop dividing after about 50 divisions.
What phenomenon is this describing?
Hayflick phenomenon
“clonal senescence”
What is the effect of mutated Dorian Gray genes?
Prolong cell life
-Not selected for, though!
TQ
Stiffness in tendons (starting at about age 60, happens faster in diabetics) results from what process?
Non-enzymatic glycosylation
TQ
- Just like when people get little barnacles or cherry angiomas or little brown spots on the backs of their hands or skin, a lot of older folks who get a mutated clonal plasma cells is perfectly benign with making antibody, and the antibody sticks up like a little spike
- From mutations that have accumulated over the lifetime
What age-related dz is this referring to?
Monoclonal gammopathy of uncertain significance
TQ
Where is the mutation located for Hutchinson-Gilford (classic progeria)?
Mutation in lamin A in father’s sperm
TQ
- Mutated DNA helicase
- Born looking old, look even older as pt ages
- Scleroderma
- Skin on knees calcifies and ulcerates
- Skin on back of hands thickens
- Feet get flat
Werner syndrome
TQ
- Mutated DNA helicase
- Butterfly rash on face
- Rash on knuckles
Rothmund’s
- Problem with DNA repair
- Mental retardation
- Optic atrophy *
- Malformations
Cockayne
- Telomeres shorten too fast
- Hair turns gray early
- Get tumors faster
- Cerebellar defects
- Spider angiomas
- IgA deficiency
Ataxia-telangiectasia
- Telomeres that are supposed to reconstitute in dividing cells (skin, marrow) do not
- Rash early
- Marrow failure eventually
Dyskeratosis congenita
Mutated insulin receptor
Leprechaunism
The immune system stay pretty much the same between young and old, except for what?
Older folks have more lymphoid follicles in the bone marrow
The best-known primary immune alteration in the elderly is what?
Mild diminution of T-cell function
What are CD28+ cells?
Why do younger people have more CD28+ than older people?
- CD28+ are cells that have never met an antigen before (i.e., virgins)
- Younger people have fought off fewer infections!
BUT – CD28+ cells respond in older folks equally as well compared to younger people
Which WBC moves and fights a little slower as you age?
Neutrophils
The ONE intervention that helps older folks mount a stronger antibody response to immunizations is what?
Aerobic exercise – running on the treadmill
What is p66?
A molecule that makes cells of older folks more likely to undergo apoptosis if they are stressed
The RANK/RANKL disconnect predisposes older folks to what?
Osteoporosis
The increase in the common cancers in older folks reflects what?
Accumulated genetic damage over a lifetime
Give an example of a primary immune alteration in the elderly.
Neutrophil function
Give a few examples of secondary immune alterations in the elderly.
- Poor nutrition * – famously interferes with immunity
- Debilitating dz
- Psychosocial issues
CD8+ cells that have already helped out with at least one infection demonstrate CD28(+/–)
CD28– !!!
Not a virgin anymore
Name 2 important autoimmune dz’s MC in older folks.
- Pernicious anemia
- Hashimoto’s
