2. Aging Flashcards
Define aging
cells tissues and organs may vary in age related change in the same person but are ultimately connected
Life span when expressed as expectancy from 65 (has/hasn’t) changed very much
hasn’t
Mortality is commonly caused by
some disease or disease process (bodies ability to withstand these diseases at
Lifespan is expressed as
life expectancy from birth or a latter age
T/F Max life-span has changed little
t
Currently the maximum verifiable lifespan is how old
122
Max lifespan reaches an asymptote at what age
115
Prove that there is a genetic link to lifespan
- Hybrid vigor (increased longevity in hybrids)
- Parental age (parents live long you will likely as well)
- Twin studies (less of a difference in lifespan between monozygotic compared to dizygotic twins)
Werner’s syndrome is what type of disease
premature aging syndrome
Inheritance pattern of Werner’s syndrom
autosomal recessive
Characteristics of Werner’s syndrome
- Growth retardation during teens
- Short
- Premature graying and hair loss
- Thin skin
- Osteoporosis
- Atherosclerosis
Functions that predictably decline with age related to the oral cavity
- Swallowing
- Tongue function
- Taste acuity for salt, bitter and umami
Other functions that predictably decline with age are
- Vital capacity
- Cardiac output
- Renal plasma flow
- Glomerular filtration rate
- Grip strength
- Reaction time
Functions that don’t change with aging are
- pH and electrolyte content in blood
- Verbal intelligence (unless dementia)
The rate of yearly loss seems to be -% of the functional capacity present at age 30
0.8-0.9%
Mortality doubles every _ (time) after age 30
7 yrs
A risk factor for most diseases is
aging
What is the Hayflick limit
a principle related to dividing cells stating that the mother cell can only produce so many daughter cells until there is a cap
When cell in the human body has a hayflick limit that is related to age
fibroblasts (have an average of 50 population doublings before a sharp decline in proliferation)
Describe the telomere theory
-Everytime a cell replicates a part of the telomere on the end of DNA is lost and one it is gone replication can no longer occur due to cell damage
What cells are exempt from the telomere theory and why
cancer cells and germ cells because there is a telomerase enzyme
When telomerase is active the telomers are (degraded/maintained)
maintained (just like the vitality of the cells)
Describe the free radical theory
-As a cell ages the number of free radicals increase which cause damage to cell membranes and create cellular waste which accumulates
Describe the cell membrane theory
As a cell ages the membrane becomes less lipid and less watery (more solid)
- Cell loses ability to transfer chemicals, electrical charge
- Toxic accumulation of lipofuscin which we se in brain, heart, lung and skin
Explain the mitochondrial decline theory
- ATP can’t be stored in the body
- Organs and cells can’t transfer ATP from each other
- As free radical damage occurs to mitochondria they produce less ATP
Describe the glycosylation theory
- AKA cross linking theory
- Binding of sugar to protein occurs in presence of oxygen (a potent free radical)
- Causes cell to loose elasticity due to glycosylation which increases stiffness in skin, BVs, etc.
Describe cross-linking theory
- Postulates that aging causes by molecules becoming irreversibly immobilized by cross- linking
- Cross-linking of collagen which makes up 25% of bodies protein
- Cross-linking theorized to affect the flow of nutrients and waste products from cells
Describe the neuroendocrine theory
- Hypothalamus is damaged over time by cortisol secreted by the adrenal gland
- Cortisol is linked to stress and is one of the few hormones which increases with age
- Receptors that uptake various hormones lose their sensitivity
- Cascade effect leads to multiple diseases seen in later age
Calorie restriction can (increase/decrease) aging process
decrease (mechanism= unknown)
Describe the evolution theory
organisms only needed to survive long enough to reproduce and care for their offspring (before medical advances)
The biologic clock theory is dictated by what two events
- Puberty
- Menopause
SIR2 gene is present in (few/some/many/all) organisms
all
SIR gene encodes _ proteins which are found where
sirtuins found in red wine
The presence of sirtuins found in red wine is significant why
because the french live longer and their diet is rich in high fat and red wine
Rapamycin is what kind of drug
antifungal agent - also can be used to suppress immune system in transplant patients
Rapamycin influences the ways cells respond to what
insulin and IGF