Free Radicals Injury Flashcards
What is a free radical
Chemical species with unpaired electron in outer orbit
Where is the formation of physiological free radicals?
Oxidative Phosphorylation
Name the 3 free radicals of oxygen
1- Superoxyde
2- Hydrogen Peroxidase
3- Hydroxyl free radical
How are the pathological free radials form?
Ionizing radiation
Inflammation
Interaction with metals (copper and iron)
Drugs ans chemicals
Which is the most dangerous free radical?
Hydroxyl free radical
Inflammation what free radical forms?
superoxyde
what is the fenton reaction ?
some metals have a strong catalytic power to generate highly reactive hydroxyl radicals
addition of the iron and the hydrogen peroxide, they are going to react together to generate some hydroxyl radicals
What is the underlying mechanism of damage in hemochromatosis
Pathologic generation of free radicals
How are made up the free radicals of acetaminophen?
- Acetaminophen gets to the liver
2. P450 system liberates free radicals
Patient that works in a dry cleaning shop, brings an abdominal ecography that reports hepatic steatosis. Denies consumption of alcohol. What could be the probable mechanism for this change to occur
- Accumulation of carbon tetraclorhide in blood
- P450 system in liver transform it to carbon triclorhide free radical that damage hepatocyte
- Cellular swelling (RER swelling)
- Decrease in protein synthesis – decrease in apo lipo proteins ( fat cant get out)
MEchanism of cell damage by free radicals
Peroxidation of lipids
Oxidation of DNA and proteins
How can the body eliminates free radicals?
Antioxidants (Vita A,C,E)
Metal carrier proteins
Enzyme
What enzymes handles each free radical?
superoxyde– SOD
Hydrogen peroxidase–Catalase
Hydroxyl free radical– Glutathione Peroxidase
Patient who had an MI and was taken to a cath lab, the artery was open, however the cardiac enzymes continue to rise. Why?
Reperfusion injury
**Blood returns with O2+ inflammatory cells and they mix with death tissue–> free radicals–> continue injury
