Describe the biochemical mechanism leading to cell membrane damage.

Mechanisms of cell Membrane Damage:

• Reactive oxygen species. Oxygen free radicals cause injury to cell membranes by lipid peroxidation.
• Decreased phospholipid synthesis. The production of phospholipids in cells may be reduced as a consequence of defective mitochondrial function or hypoxia, both of which decrease the production of ATP and thus affect energy-dependent biosynthetic pathways. The decreased phospholipid synthesis may affect all cellular membranes, including the mitochondria themselves.
• Increased phospholipid breakdown. Severe cell injury is associated with increased degradation of membrane phospholipids, probably due to activation of calciumdependent phospholipases by increased levels of cytosolic and mitochondrial Ca2+.
• Cytoskeletal abnormalities. Cytoskeletal filaments serve as anchors connecting the plasma membrane to the cell interior. Activation of proteases by increased cytosolic calcium may cause damage to elements of the cytoskeleton.