Ministry of education
King Abdulaziz University
Faculty of medicine
Rabigh branch
Assignment of pathology
“cell injury”
Assignment of cell injury
Q: Explain the mechanism of cell injury by free radicals and give an example.
1- Lipid peroxidation
(oxidative degradation of lipids)
Destruction of unsaturated fatty acids by free
radicals, because they contain multiple double
bonds in between which lie methylene groups
(CH2) that possess especially reactive
hydrogens.
2- Protein destruction:
cross linking proteins forming
disulfide bonds (S-S) → inactivate enzymes, &
polypeptide degradation
3- DNA alteration:
single strand break in DNA
mutation that interfere with cell growth