14 Pathology of Degeneraton and Aging
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Transcript of 14 Pathology of Degeneraton and Aging
Pathology ofPathology of Degeneration & AgeingDegeneration & Ageing
dr. Al Munawir, M.Kes., Ph.D.Laboratorium Patologi
AnatomiFakultas Kedokteran Universitas Jember
Cell Injury:
When I look into the future, When I look into the future, it's so bright it burns my eyes…!it's so bright it burns my eyes…!
– Oprah Winfrey
Ageing
Cell Injury:
Ageing:“Progressive time related loss of
structural and functional capacity of cells leading to death”
Senescence, Senility, Senile changes. Ageing of a person is intimately related
to cellular ageing. Blood vessel damage precedes ageing.
PHYSICAL AGING PROCESS
WHEN DOES OLD AGE BEGIN?
Cell Injury:
DEFINITION OF AGING Old and aging depends on the age
and experience of the speaker. Chronological age - number of
years lived Physiologic age - age by body
function Functional age - ability to
contribute to society
Cell Injury: CHRONOLOGICAL CATEGORIES
Young-Old - (ages 65 - 74)
Middle-Old - (ages 75 - 84)
Old-Old - (age 85 and older)
Cell Injury: FRAIL ELDERLY
Characteristics: Poor mental and
physical health Low socioeconomic
status Predominantly female Possibly isolated living
conditions More and longer
hospital stays, and More money spent on
health care and drugs
PHYSICAL THEORIES OF AGING
What causes the body to age?
PROGRAM THEORY
Cells replicate a specific number of times and then die. Happens again, and again in lab experiments.
Cell Injury:
ERROR THEORY
The structure of DNA is altered as people age
Due to alterations, DNA not read correctly
Results in transcription and translation malfunction
Results in aging/illness/ cancer directly, or indirectly
CELLULAR THEORY
Normal wear and tear causes cells to function
improperly
Cell Injury:
FREE RADICAL THEORY
Lipids in cell membranes are exposed to radiation or free radicals
Cell membrane ruptures and cell dies
In test tubes this actually occurs
Cell Injury: NUTRITIONAL MODEL THEORY
If animal fed 50-60% less than it eats on its own - lives longer
Assumption: Lean mass, as opposed to adipose tissue results in greater health
COLLAGEN THEORY OF AGING
As we age, collagen in body ages also. Causes hypertension and other
organ malfunctions
Cell Injury: MUTATING AUTO-IMMUNE THEORY
Cells have normal functions - secrete normal proteins
As cells age - mutate and secretions viewed as foreign by body
Solicits immune response Shuts cell down Cause biological errors and entire
organ malfunctions
Cell Injury:
NEURO-AGING THEORY
All cells undergo nervous system degeneration
Results in changes in hormonal release
Leads to decline in cell function
NONE OF THESE THEORIES TOTALLY ACCEPTED
Scientists hypothesize it might be combination of
several or all
Cell Injury:
PHYSIOLOGICAL AGING OF THE HUMAN BODY
BY SYSTEMS
Cell Injury:
SKIN, HAIR, NAILS Loss of subcutaneous fat Thinning of skin Decreased collagen Nails brittle and flake Mucous membranes drier Less sweat glands Temperature regulation
difficult Hair pigment decreases Hair thins
Cell Injury:
EYES AND VISION Eyelids baggy and wrinkled Eyes deeper in sockets Conjunctiva thinner and
yellow Quantity of tears decreases Iris fades Pupils smaller, let in less
light Night and depth vision less “Floaters” can appear Lens enlarges
Cell Injury: EYES AND VISION CONT.
Lens becomes less transparent
Can actually become clouded
Results in cataracts
Cell Injury: EYES AND VISION CONT.
Accommodation decreases Results in presbyopia Impaired color vision, also -
especially greens and blues Because cones degenerate
Cell Injury: EYES AND VISION CONT.
Predisposed to glaucoma
Increased pressure in eye
Decreased absorption of intraocular fluid
Can result in blindness
Cell Injury:EYES AND VISION
CONT.
Macular degeneration becoming more frequent
This is the patch of retina where lens focuses light
Ultimately results in blindness
Reason for current increase in this condition unknown
Cell Injury: EARS AND HEARING LOSS
Irreversible, sensorineural loss with age
Men more affected than women
Called presbycusis Loss occurs in higher
range of sound By 60 years, most adults
have trouble hearing above 4000Hz
Normal speech 500-2000Hz
Cell Injury: RESPIRATORY SYSTEM
Lungs become more rigid
Pulmonary function decreases
Number and size of alveoli decreases
Vital capacity declines Reduction in
respiratory fluid Bony changes in chest
cavity
Cell Injury: CARDIOVASCULAR SYSTEM
Heart smaller and less elastic with age
By age 70 cardiac output reduced 70%
Heart valves become sclerotic
Heart muscle more irritable
More arrhythmias Arteries more rigid Veins dilate
Cell Injury: GASTROINTESTINAL SYSTEM
Reduced GI secretions
Reduced GI motility Decreased weight of
liver Reduced
regenerative capacity of liver
Liver metabolizes less efficiently
Cell Injury:
RENAL SYSTEM After 40 renal function
decreases By 90 lose 50% of function Filtration and
reabsorption reduced Size and number of
nephrons decrease Bladder muscles weaken Less able to clear drugs
from system Smaller kidneys and
bladder
Cell Injury: REPRODUCTIVE SYSTEM
Male: Reduced testosterone level Testes atrophy and soften Decrease in sperm
production Seminal fluid decreases
and more viscous Erections take more time Refractory period after
ejaculation may lengthen to days
Cell Injury: REPRODUCTIVE SYSTEM
Female: Declining estrogen and
progesterone levels Ovulation ceases Introitus constricts and
loses elasticity Vagina atrophies -
shorter and drier Uterus shrinks Breasts pendulous and
lose elasticity
Cell Injury: NEUROLOGICAL SYSTEM
Neurons of central and peripheral nervous system degenerate
Nerve transmission slows Hypothalamus less effective in
regulating body temperature Reduced REM sleep, decreased
deep sleep After 50% lose 1% of neurons
each year
Cell Injury: MUSCULOSCELETAL SYSTEM
Adipose tissue increases with age
Lean body mass decreases Bone mineral content
diminished Decrease in height from
narrow vertebral spaces Less resilient connective
tissue Synovial fluid more viscous May have exaggerated
curvature of spine
Cell Injury:
IMMUNE SYSTEM Decline in immune function Trouble differentiating
between self and non-self - more auto-immune problems
Decreases antibody response
Fatty marrow replaced red marrow
Vitamin B12 absorption might decrease - decreased hemoglobin and hematocrit
Cell Injury:
ENDOCRINE SYSTEM Decreased ability to
tolerate stress - best seen in glucose metabolism
Estrogen levels decrease in women
Other hormonal decreases include testosterone, aldosterone, cortisol, progesterone
Cell Injury:
Factors affecting Ageing: Genetic 60% & Environmental 40% Clock genes, (fibroblast culture) Werner’s syndrome. Age gene on Chromosome 1. “Age” is a character from female
parent. Mammalian mitochondria come from
ovum.
Cell Injury:
Factors affecting Ageing: Environmental factors (40%) Trauma Diseases – Atherosclerosis, diabetes Diet – malnutrition, obesity etc. Psychological & Social health –
stress.
Cell Injury:Ageing – Morphologic changes:
Easy bruising – fragile capillaries. Glycosylation of lens proteins – Accumulation of Lipofuscin pigment
– Brown atrophy. Blood vessel hardening –
arteriosclerosis, atherosclerosis.
Cell Injury:Ageing – Morphologic changes:
Skin – elastosis, hairloss, atrophy, bruising.
Joints – osteoarthritis. Immunity – immunosuppression. Heart – Brown atrophy, CVS – arterio & atherosclerosis, MI,
stroke. Neoplasms CNS – cerebral degeneration.
Cell Injury:Atrophy – Senile / Alzheimer's
Cell Injury:
Elastosis of skin:
Cell Injury:
Pathology of elderly
Cell Injury: