confused about cholesterol
I'm trying to understand the opinion of PB's on cholesterol but the info I'm reading on here is confusing and sort of sounds contradictory to each other. So far I have read How to interpret your cholesterol results, Peter Attia's write up part 1 and 2, The definitive guide to cholesterol, & Griffs thread.
How to interpret your cholesterol results says LDL particles oxidize. Once oxidized, LDL particles are taken up by the endothelium to form atherosclerotic plaque so they don’t damage the blood vessel. Apart from not understanding what is meant by the atherosclerotic plaque forms so they don't damage the blood vessel??? It contradicts Peter Attia's write up part 1 and 2 which says after a LDL particle gets into the sub-endothelial space and takes up “illegal” residence (i.e., binds to arterial wall proteoglycans), it is subject to oxidative forces, and as one would expect an inflammatory response is initiated.
So one says oxidation occurs to LDL particles, THEN it is deposited into the endothelium, the other says an LDL particle displaying ApoB deposits into the endothelium of arteries and THEN undergoes oxidation. Im confused which one is right... oxidize before or after depositing into the endothelium?
Also I cant seem to find something that has explained WHY these LDL particles displaying apoB lodge into the endothelium of arteries. Peter Attia's write up part 1 and 2 says "it is a gradient driven process " but I have no idea what that means? Do we actually know why LDL's lodge in arterial walls?
No, just lots of theory and speculation. A gradient driven process describes the thermodynamic principle of matter trying to reach its lowest energy state. High concentrations of particles want to expand into an area of low concentration just like heat wants to flow from a hot object to a cold object. The more particles of LDL you have in your blood, the more frequently they will collide with your arterial wall. However, whether or not they will enter and get stuck in the endothelium depends on other factors which are not well understood. It isn't clear, at least not to me, if LDL particles get stuck because they are oxidized or if they get oxidized because they are stuck. Attia took a strong position in his cholesterol series that the only thing that matters is LDL-P. He has backed away from that position now saying we just do not know exactly what drives the plaque forming process.
Originally Posted by danhaych
Is there a difference in purpose between the plaque that is deposited between the intima and media layers and plaque that is just deposited on the wall of a artery? I read somewhere what I thought I was understanding as the role of LDLs is to transport cholesterol to areas of arteries that have been damaged, it deposits the cholesterol on the wall like a bandaid, once the damage is healed the HDLs come along and remove the bandaid.
Part of your problem in understanding may be reading different posts from different time periods. All of them where likely valid when they were written, but understanding of the mechanisms at play and the best proxy (as an indicator for CVD) is also changing.
In studying this myself the only conclusion I can reach is that even the most advanced lipid panels are inadequate to say the least.
Last edited by Neckhammer; 04-12-2013 at 08:50 PM.