Pathophysiology of Aging Flashcards
Process that occurs in the lifespan of every creature. Involved every molecule, cell, and organ in the body.
Aging
Any cells forming from the body of an organism, as opposed to germline cells. Have a finite replicative capacity
Somatic Cells
Progressive deterioration of many bodily functions over time producing negative factors with age.
Senescence
Genetic material based cells that can be passed down to a child
Germ Cells
Aging of the Heart
- Heart Tissue thickens
- Maximal O2 consumption decreases by 10% in men and 7.5% in women
- Decline in O2 consumption occurs because of the heart’s pumping rate and the body’s O2 extraction capability decreases with time
Aging of the Arteries
- Arteries stiffen
- Moving the blood through inelastic arteries required the heart to pump blood with more force
- Greater stress placed on the heart
Aging of the Bones
Young: Bone mineral is lost and replaced in the body
- Age 35,: Bone mineral loss > replacement
- Menopause: Bone mineral loss»_space; Replacement
Suspected factor in women that contributes to greater osteoporotic rate?
Estrogen
How to treat osteoporosis?
- 1,200 Calcium/Vit D
- Exercise
Pathophysio of Rheumatoid Arthritis
Synovium becomes inflammed and produces excess fluid.
Later on, the cartilage becomes rough and pitted.
Pathophysio of Osteoarthritis
Hypertrophy and spurring of bone and erosion of cartilage
Alzheimer’s Disease
- Progressive Brain Dz
- Memory Impairment
- Accumulation of the beta-amyloid protein, which leads to nerve cell death
- Inflammation has been implicated and oxidative stress
Aging of the Lungs
Maximum Breathing declines 40% between ages 20 and 70
Aging of the Kidneys
Kidneys remove less waste from the blood when they are older
Aging of the Bladder
Bladder capacity declines
Age-relaed loss of muscle mass, strength and function.
Sarcopenia
What does sarcopenia cause?
- Physical Disability
- Loss of independence
- Mortality
- Impaired QoL
What are some factors that can lead to sarcopenia? (Cellular level)
- Mitochondrial Mutations, Deletions, Dysfunction
- Impaired Autophagy
- Impaired DNA
- Impaired RNA
- Impaired Protein and Lipid Repair Mechanisms
- Apoptosis
- Dysfunctional Iron Homeostasis
Aging of the Muscle and Body Fat
- 65-70+ yo: Weight Decrease due to decreasing muscle tissue and body fat
- Intramuscular Fat Deposits Increase
Aging of the Neuro System
- Decreased number of axons that connect neurons
- Motor neurons - 29% loss
- Ischemia
- Neurotoxins
- Apoptosis
- Parkinson’s
What is the intervention for Parkinson’s Dz?
Strength Training
Aging of the Eyes
- Age 40+: Focusing close up may become more difficult
- Age 50+: More susceptibility to glare, seeing low illumination levels, difficulty detecting objects in motion
- Age 70+: Decline in ability to distinguish fine details
Aging of the Ears
- Listening to higher frequencies becomes difficult with age
- Declines faster in men than women
Theories of Aging
- Molecular - Telomeres
- Molecular - Age Genes
- Cellular - Free Radical/Mitochondrial
- Cellular - Apoptosis
- Cellular - Protein Aggregation
- Cellular - Inflammation
- System Theories - Immune function and Endocrine Function
Telomere and Age Genes Theory of Aging
- Lengthening Telomeres may increase the Risk for Cancer
- Telomere Shortening Reduces the Risk of Cancer
**THIS IS FROM THE PPT. THE HANDOUT SAYS SHORTENING CAN LEAD TO DEATH
Cellular Theory of Aging
Aging is due to the cumulative effects of damage wrought by free radicals on the mitochondrial DNA and function
Free Radical Theory of Aging
Chronic Exposure to oxidants during a life-span and oxidants cause oxidative stress.
Oxidative Stress = Protein Damage; Lipid Damage; DNA Damage
What are antioxidants used for?
- Counteract Formation of Free Radicals
- Examples: Vitamin C and E, Superoxide Dismutase (SOD), Catalase, Gluthione Peroxidase
*** NO and H2O2 have important biological functions and are free radicals, we don’t want to counteract this.
Antioxidants have been shown to do what to the effects of physical exercise?
Prevent the beneficial health-promoting effects
Inflammation Theory of Aging
- Based on evidence for increased levels of inflammation (cytokines) with age
- Level of Inflammation is linked to free radical production
Aging and Protein Aggregation
- Stressors leading to protein aggregation leads to non-functional cells
- Stressors leading to damaged/defective proteins that are degraded properly allow for normally functioning cells
Glycoxidation Theory of Aging
- Cooking of foods accelerate the Browning or Maillard Reaction
- The toxic substances formed can lead to cellular dysfunction, mutations, and cancer
Over the lifespan of the human it seems that ____________ increases to a greater extent with age in humans compared to monkeys.
Pentosindine (glycoxidation product)
Neuroendocrine Theory of Aging
Hormones are vital for repairing and regulating our bodily functions, and when aging causes a drop in hormone production, it causes a decline in our body’s ability to repair and regulate itself as well. Moreover hormone production is highly interactive. The drop in production of any one hormone is likely to have a feedback effect on the whole mechanism, signaling other organs to release lower levels of other hormones which will cause other body parts to release lower levels of yet other hormones.
Immune System Theory of Aging
- B-cells grow in the bone marrow and one of their functions is secreting antibodies when they detect the presence of infectious agents or antigens
- T-cells are produced by the thymus, which decreases in size as we age
- Cytotoxic T-cells attack infected cells directly
- T-cells that work properly tend to decrease in aging, even though the population of T-cells remains constant.
A study shows that cognitive impairment before and after a sepsis episode…
Increases greatly!
Anddddd all the science is over.
Have a blessed day!
