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Animation/ 2D Gradient Gel
 Take a look at the brochure!
Why analyze HDL?
The effects of lowering LDL are significant. In major studies, reducing LDL by 20-60% results in a reduction of cardiac event rates in the range of 20-40%. However, 60-80% of events still occur.
When studying HDL-C, there is a 2-3 % reduction in cardiac events for each 1mg/dL increase of HDL-C (Gordon, Circulation, 1989). Looking deeper at HDL, several sub fractions of HDL have been identified. These sub fractions, in data from Asztalos and others, suggest there is more to HDL than just HDL-C. For example, for every 1 mg/dl increase in alpha 1 HDL (α-1 HDL) in the Framingham Offspring Study, there was a 26% decrease in risk of CHD (p<0.001). Also, HDL particles were significantly better CHD predictors than HDL-C values (Asztalos et al ATVB 2004). The Boston Heart HDL MapTM assay utilized by Boston Heart Lab has been run on participants not only in the Framingham Offspring Study, but also in VA-HIT, HATS and other studies. The results indicate the importance of HDL sub fractions and suggest possible treatment strategies to modify particle distribution accordingly.
Boston Heart HDL MapTM
Boston Heart Lab is the only lab using the proprietary, 2D gel electrophoresis to analyze HDL sub fractions. With this exclusive method, all 5 main HDL sub particles, which contain apoA-1, can be quantitated.
The Boston Heart HDL MapTM analysis allows for the precise measures of the small discoidal pre-β 1 HDL and α-4 HDL as well as the spherical α-3 HDL particles that pick up free cholesterol from macrophages and smooth muscle cells of the vessel walls of extra hepatic tissues. Particles turn spherical as they grow when free cholesterol is esterified by lecithin cholesterol acetyltransferase (LCAT), sending the cholesterol esters to the core of the particle. A clear separation among the subclasses and separation between the α-mobility and preβ-mobility HDL particles can presently be achieved only with this 2Dgel electrophoresis method. In 1Dgel electrophoresis, the pre-β 1 HDL cannot be identified. It ends up in the α-2/ α-1 region and makes the distinction between the particles impossible.
As more cholesterol and other fats like phospholipids, and other apolipoproteins are picked up, the growing particles mature into larger α-2 and α-1 HDL. Through a scavenger receptor B-1 (SR-B1) mediated pathway, larger α-2 and α-1 HDL have the potential to unload and deliver, cholesterol to the liver for excretion into the bile. This regenerates the smaller pre-β1 and the process can start all over again.
High levels of the small preβ-1 and α-3 HDL particles are markers of high risk for the presence of clinical or subclinical vascular disease, while high levels of the large α-1 HDL is a marker of protection from heart disease.
Increased amounts of the large α-mobility HDL particles (green) are generally associated with decreased CHD risk, while increased amount of the small HDL particles (red) are generally associated with increased CHD risk.
Boston Heart Lab’s proprietary 2D gel electrophoresis separation method allows not only for calculating the size distribution, but also the α-1/preβ-1 ratio which is a powerful marker of CHD risk. It has been shown that the α-1/preβ-1 ratio is most effective for estimating the efficacy of specific lipid-lowering interventions (diet, exercise, weight loss, and drugs, especially statins).
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