CELLULAR INJURY AND CELL DEATH Flashcards
• Alteration in cell structure or function due to stress or pathologic stimuli
• This is the most common response of the cells in almost all types of diseases.
CELLULAR INJURY
CAUSES OF CELLULAR INJURY
HPCIING
Hypoxia
Physical Agents
Chemical Agents and Drugs
Infectious Agents
Immunologic Reactions
Nutritional Imbalances
Genetic Abnormalities
There is loss of oxygen level on that specific organ or on that specific cell
Hypoxia
This can be due to accidents or any form of physically-induced type of injury
Physical Agents
Chemical and drugs that can be harmful to the body
Chemical Agents and Drugs
• Bacteria, parasites, and the viruses.
Infectious Agents
• Allergies
Immunologic Reactions
• Comes from parents; passed to you during pregnancy
Genetic Abnormalities
There is no homeostasis on the tissues that resulted to cellular injury
Nutritional Imbalances
MORPHOLOGICAL ALTERATIONS
• Generalizing swelling of cells and organelles
• Blebbing of plasma membranes
• Detachment of ribosomes from ER
• Clumping of nuclear chromatin
• The first and foremost or the earliest manifestation of cell iniurv
Generalizing swelling of cells and organelles
This one is due to increase in the number of free radicals and the plasma membrane will now protrude.
The protruded portion of the lasma membrane is called the Blebs.
Blebbing of plasma membranes
The ribosomes wil now be detached on the endopasmic reticulum, specifically the rough endoplasmic reticulum.
Detachment of ribosomes from ER
Cell injury vs Cell suicide
Necrosis vs Apoptosis
Cell size
Apoptosis: Reduced
Necrosis: Enlarged
Plasma membrane
Apoptosis: Intact
Necrosis: Disrupted
Cellular contents
Apoptosis: Intact
Necrosis: Enzymatic digestion
Adjacent inflammation
Apoptosis: No
Necrosis: Frequent
Nucleus
Apoptosis: Fragmentation into nucleosome size
Necrosis: PKK (Pyknosis > Karyorrhexis > Karyolysis)
Physiologic or Pathological
Apoptosis: Physiologic
Necrosis: Pathologic
(clumping) nucleosome-size
-> fragments (fragmentation) ->
(dissolution)
Pyknosis
Karyorrhexis
Karyolysis
-• Induced by a tightly regulated suicide program in which cells destine to die activate enzymes that degrade the cells’ own proteins and nuclear DNA
APOPTOSIS
Presence of cleaved _______ is a marker for cells undergoing apoptosis
active caspases
These are cysteine proteases that can cleave the aspartic residue.
CASPASES
Apoptosis
Cells break up into______, which are tasty targets for_____
apoptotic bodies
phagocyte
• The outcome usually of the cells that undergo apoptotic death is_____, the cell membranes and components are still_____, and there is no any form of_____.
shrunken
intact
leakage
The cause of this one can be hypoxia, physical agents, chemical agents, or biological products
Apoptosis