Wound Healing Flashcards
Define wound healing.
Restoration of tissue architecture and function after an injury
What is the difference between wound healing and wound repair?
Healing = complete restoration of tissue
Repair = incomplete restoration
What are the steps of wound healing model?
- Damage
- Inflammation
- Removal of dead tissue
- Replacement by 4.scar or tissue
- =healing
What are the three cell types in our body?
- Labile cells
- Permanent cells
- Stable cells
What are examples of labile cells? Can they regenerate?
Cells that have high turnover rate, like epithelium. Chance of regeneration is excellent
What are examples of stable cells? Can they regenerate?
Cells that normally do not undergo proliferation, but remain capable of cell division.
Chance of regeneration is good
What are examples of permanent cells? Can they regenerate?
Neurons
Cardiac muscle
Skeletal muscle
Heals by scarring
What enables a tissue to undergo regeneration?
Presence of stem cells
What determines if a tissue that is able to undergo regeneration undergoes scarring?
The extent of damage
What are the three phases of healing?
- Inflammatory
- Proliferative
- Remodeling (maturation)
What are the two events that occur during inflammation? When does this occur?
Clot formation, chemotaxis
Usually first week
What are the three events that happen in proliferation? When does this occur?
- Re-epithelialization
- Angiogenesis
- Provisional matrix
Second week
What are the two events that occur in the maturation (remodeling) stage
Collagen matrix
Wound contraction
Third week
What is the major molecule that signals angiogenesis? What cell secreted this?
VEGF–macrophages secrete this
What are the two major events that happen in angiogenesis?
Capillary budding
Endothelial cell proliferation
What cell is the “director” of wound healing? Why?
Macrophage, since is secretes cytokines ike VEGF
What is the major chemical in fibrogenesis? What cells secrete this?
TGF-beta–macrophages
What are the two major events that occur in fibrogenesis?
- Fibroblast activation/proliferation
2. Collagen deposition
What are the two enzymes secreted by macrophages that facilitate debridement of tissue/debris?
Collagenase
Elastase
What are the two types of chemicals secreted by macrophages that have an antimicrobial activity?
Nitric acid
ROS
What are the five chemicals secreted by macrophages that promote chemotaxis?
**TGF-beta** IL-1 TNF KGF-7 PDGF
What are the three chemicals secreted by macrophages that stimulate angiogenesis?
VEGF
FGF-2
PDGF