Lipid Peroxidation

Question 1

What are active Fe(II) chelates?

Answer 1

ADP, ATP, albumin, hame, Hb, Mb, CytC.

Question 2

What are the molecular features of MDA?

Answer 2

Formed from the per oxidation of PUFAs with more than 2 double bonds.
Less reactive than HNE
Enolate ion at physics pH
Metabolised to acetate.

Question 3

What is 4-HNE?

Answer 3

N-6 PUFA per oxidation product

An unsaturated aldehyde = alkenal.

Question 4

What are F2-isoprostanes?

Answer 4

Prostaglandin F2-like compounds non-enzymatically formed in vivo by free radical per oxidation of arachidonic acid.
Very bioreactive and produced in far greater quantities than cyclooxyrgenase derived PGs.

Question 5

How does lipid peroxidation impact the plasma membrane?

Answer 5

Damage to membrane proteins - HNE and MDA adducts form.
Membrane fluidity decrease (phospholipid exchange between 2 monolayers –> increased leakiness of membrane to Ca and other ions).

Question 6

What did West et al show in 2010?

Answer 6

Link between inflammation, OS and blood vessel formation.

Lipid oxidation products (CEP) promoted blood vessel formation via MyD88-dependent TLR2 signalling.