Pathophysiology of Aging Flashcards
What are the are the clinical manifestations of senescence?
Age related diseases
In relationship to other animals where do humans rank in regards to life span?
Very high! the turtle has us beat though :( Damn turtles (we have a life span of 122 years?)
T/F: There are not clear species-specific differences in maximum life-span
False there are
What is the definition of maximum life span?
The greatest age reached by any member of the species
What is the name of the person holding the record for longest life span among humans?
Jeanne Louise Calment
Aging:
Process that occurs in the lifespan of every creature.
What does aging involve in regards to the human body?
Involves every molecule, cell, and organ in the body.
Senescence:
Progressive deterioration of many bodily functions
over time producing “negative factors” with age.
Somatic cells:
Any cell forming the body of an organism; have an infinite replicative capacity
Germ cells:
Cells that have genetic material, which may be passed to a child.
What questions does the process of aging present?
What causes aging? (one cause or multiple)
Does aging cause the disease or do the diseases cause aging?
What happens during CV disease as compare to CV aging?
Aging: arteries become stenosed via stiffining
Disease: arteries become fat and plaque filled
T/F: Aging is different from person to person.
True
T/F: Within the same individual, organs and tissues age at the same rate.
False, they age differently
What happens to the heart with age?
- Heart tissue thickens with age.
- Maximal O2 consumption decreases
Why does the O2 consumption decrease with age?
Decline in O2 consumption occurs because the heart’s pumping rate and the body’s O2 extraction capability decreases with time
What happens to the heart with age?
- Arteries stiffen with age.
- Moving the blood through the inelastic arteries requires the heart to pump blood with more force
- Greater stress is placed on the Heart.
Describe bone loss in the body and how it changes with age:
When young, bone mineral is always lost and replaced in the body Around age 35, the loss becomes greater than the replacement The loss is even greater in women after menopause
How do we slow osteoporosis?
Calcium, Vitamin D and Exercise
What happens in rheumatoid arthritis?
Synovium becomes inflamed and produces excess fluid and later the cartilage be comes pitted and rough
What is an example of a neurodegenerative disease?
Alzheimer’s Disease (AD)
What is Alzheimer’s disease?
Progressive brain disease
Memory impairment
Accumulation of the beta-amyloid protein, which leads to nerve cell death.
What happens to the lungs with normal aging?
Maximum breathing declines 40% between ages of 20 and 70
What happens to the kidneys with normal aging?
kidneys remove less waste from the blood
What happens to the bladder with normal aging?
bladder capacity declines
What is sarcopenia?
Age-related loss of muscle mass, strength and function
Mitochondrial mutations, deletions and dysfunction, impaired autophagy,
impaired DNA, RNA, protein and lipid repair mechanisms, apoptosis, dysfunctional iron homeostasis may represent some of mechanism driving the onset and progression of muscle loss.
What is sarcopenias effect on aging?
Contributes to physical disability, loss of independence, and mortality, impaired quality of life.
What is the relationship between muscle, fat and aging?
From age 65 on, weight decreases by decreasing muscle tissue and body fat; However, intramuscular fat deposits increase.
What happens in our brains as we age?
There is a loss of Motor Neurons:
Age decreases the number of axons that connect
neurons, as a result neurons don’t function properly
What causes the loss of neurons with aging?
– Ischemia
– Neurotoxin
– Apoptosis
- Parkinson Disease
What happens to sight with normal aging?
- At 40: focusing close up may become difficult.
- At 50: more susceptibility to glare, difficulty seeing at low illumination levels and more difficulty detecting objects in motion.
- At 70: ability to distinguish fine details begins to decline.
What happens to hearing with normal aging?
Listening to higher frequencies becomes difficult with age.
Does sex have a role in the loss of hearing with age?
Yes, hearing declines faster in men than in women.
What are the different theories behind why we age?
- Molecular Theories (Telomeres; Age Genes)
- Cellular theories
3) System Theories (Immune function and
Endocrine Function changes
What are the cellular theories of aging?
- Free radical/mitochondrial
- Glycoxidation Theory of Aging
- Apoptosis Theory of Aging
- Protein Aggregation Theory of Aging
- Inflammation Theory of Aging
What role do telomeres have in aging?
Lengthening telomeres may increase the risk for cancer.
Shortening reduces the risk for cancers
What is the mitochondrial theory of aging?
Oxidative damage to mitochondrial DNA is inversely related to maximum life span in the heart and brain of mammals
What is the free radical theory of aging?
There is a chronic exposure to oxidants during a
life-span and oxidants cause oxidative stress
What happens when oxidant (free radicals) formation is greater then antioxidant defenses?
Oxidative Stress:
• Protein damage
• Lipid Damage
• DNA damage
What is the oxidative stress theory of aging?
Antioxidants:
• Counteract formation of free radicals
• However, some radicals i.e., Nitric oxide and hydrogen peroxide have important biological functions
T/F: Mitochondrial are a source of ROS.
True
What is ROS?
Reactive oxygen species
T/F: Antioxidants prevent health-promoting effects
of physical exercise in humans
True
What is the inflammatory theory of aging?
The molecular inflammation hypothesis of aging is based on evidence for increased levels of inflammation (cytokines) with age
What is the level if inflammation linked to?
Level of Inflammation is Linked to Free
Radical Production
T/F: Protein aggregation can lead to in increase in over all aging?
FALSE, leads to increased aging and decreased life span
What is the glycooxidation theory of aging?
Cooking of foods accelerates the Browning
or Maillard reaction. The toxic substances formed can lead to cellular dysfunction, mutations and cancer
Over the life span of the human, what increases, molecularly, to a greater extent with age in humans compared to monkeys?
Pentosindine (glycoxidation product)
What are the “system” theories of aging?
- Neuroendocrine
2. Immunological
What are hormones?
Chemicals in the body that regulate, stimulate, and
control the function of various tissues and organs.
Where are hormones made?
Glands
What are the components of the immune system?
B-cells
T-cells
What is the role of B cells?
Function in secreting antibodies when they detect
the presence of infectious agents or antigens.
Where are B cells formed?
Bone marrow
What is the role of T cells?
Cytotoxic T-cells attack infected cells directly.
Where are T cells formed?
Produced by the thymus, which decreases in size as we age.
What happens to T cells as we age?
T-cells that work properly tend to decrease in aging, even though the population of T-cells remains constant.
What are some of the broad factors which determine the pathophysiological rate of aging?
– Genetic changes with age – Cellular changes with age – Hormonal changes with age – Environmental exposures – Sepsis and Trauma Events during Life-span
What are key interventions to maintain mobility?
Testosterone
Physical activity
Asprin
Resveratrol
What are the Hayflick Assumptions? (for cells in culture)
(1) Proliferative lifespan: Normal cells cannot divide indefinitely
(2) Proliferative lifespan is related to the donor’s age
(3) Proliferative lifespan is correlated to the species lifespan
