Glycocalyx: Protection of the Linings of Your Arteries
None of us wants to develop heart disease if we can avoid it. After all, heart disease is the number one killer of humans. Age we age, we’ll all get it, but wouldn’t it be nice if we could delay the onset of it so that we could live a longer healthier life?
Science has discovered a remarkable barrier inside the lining of every artery and capillary of your body that helps protect them from damage. This lining is called the endothelium, and the thin layer that protects it is called the glycocalyx. If we can protect this inner lining from damages that can occur as we age, perhaps we can decrease the risk of you developing heart disease.
The Endothelial Glycocalyx
The endothelium is a layer of flat cells that line the inside of all your arteries and capillaries, collectively called your vasculature. Think of this as a mosaic of tiny tiles placed side by side on the inside of every artery in your body that lines their inner sides. These cells produce the glycocalyx to protect them from damage. This thin endothelial glycocalyx lining also has physiologic functions to help the flow of blood occur within the vasculature.
The glycocalyx lining is continuously being produced to coat the inner lining cells. It is composed of many compounds, but most of it is heparin (a blood thinner) and chondroitin sulfate (a slick substance such as is present in your joints). Together they protect the endothelial layer of cell from damage. Damage to the glycocalyx can in turn result in exposure to the rushing blood and other components passing through your blood vessels.
Functions of the Glycocalyx
The glycocalyx is like a fuzzy mesh that covers the endothelium and protects it while allowing nutrients to go through the mesh to feed your cells and tissues. It has multiple functions:
- It decides on which and how much nutrients, compounds and fluids can come through its mesh and those that don’t, partly because the structure of the molecules of the mesh. This is called permeability of the mesh., 
- It also has a negative charge, and repels compounds with similar negative charges. This is like when you put two negative ends of a magnet next to each other: they repel each other.
- It contains heparin and other compounds within its structure which are a natural blood thinners, regulating coagulation, which prevents blood from clotting (coagulating) on the surface of the walls as it rushes by.
- It is a physical barrier preventing shear stress from injuring it as the blood rushes by, and inadvertent adhesion of platelets and white blood cells attaching onto the vascular inner walls.
- It regulates the entrance of immune cells and certain compounds into the tissues to produce their effects. immune responses, fight off foreign bacteria or viruses, assist in wound healing, and clean up debride from metabolism. This helps prevent cardiovascular disorder from occurring by decreasing formation of atherosclerosis.
- It stimulates endothelial nitric oxide (NO) release, which helps in dilation of vessels with subsequent increase in coronary artery blood flow.
The shear stress of blood flowing through your vessels can damage the glycocalyx making it thinner and unable to protect the endothelial cells well. This shear force then may “lift” the endothelial cells off their base, creating a “mini-cave” that can collect particles under the cells. If bad cholesterol (LDL) and other particles become lodged under these cells, the accumulation of this debride can become inflamed, especially if LDL is oxidized. These then form bumps within the arteries called plaques, creating atherosclerosis. If you accumulate enough of these plaques, the arteries become stiff, inflamed, and hardened, otherwise called arteriosclerosis.
These changes are the hallmarks of cardiovascular disease. If we can prevent these changes in the endothelium from occurring, we could reduce or slow the development of heart disease. Heart disease is the number one killer of humans. If we can reduce your risk of developing this, we could potentially help you live longer and healthier.
People who have chronic medical conditions, such as diabetes or heart disease, have a poor glycocalyx. Having high blood sugar, hyperglycaemia, such as seen in diabetics, results in a destruction of the glycocalyx. In individuals with hyperglycaemia, the thickness of their glycocalyx is around 50% thinner compared to others without diabetes. They are thus even more prone to develop cardiovascular disease from further destruction of this lining, resulting in many of the complications seen in diabetes. This glycocalyx destruction may be the cause of the microvascular disease that occurs in diabetes that results in the retinal and kidney problems seen in diabetes.
There are no drugs available today that could specifically increase the synthesis of the glycocalyx, refurbish or regenerate it, or prevent its degradation. They just do not seem to be available. A novel supplement from seaweed native to Asia contains a substance, Rhamnan sulfate, which may be a compound that could potentially help protect this glycocalyx from damage. (see blog article on Rhamnan)
Rhamnan sulfate is a substance that can repair, rejuvenate and rebuild the endothelial glycolalyx in many ways to improve its health. Using this on a regular basis may be beneficial to anyone, but particularly those who are at risk of having impaired glycocalyx. Rhamnan is discussed further in our blog article on this supplement.
How do you know if your glycocalyx could be damaged?
There are many tests that evaluate your heart. A new test that has recently become available is the PULS Cardiac Test. This is a simple blood test that evaluates several components of your blood and, through its algorithm, can determine if your endothelium is healthy or needs improvement. The results of the test can tell you your heart age and the relative risk of you having a coronary event compared to others with healthy endothelium.
Knowing your heart age is important for people to realize that they must maintain their health on a daily basis. Read our blog article on the PULS Cardiac Test for further information . Health is a choice your must make every day. We at TrueMD are passionate about helping you improve your health. Getting the PULS Cardiac Test is one method to help us know how to help you.
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Disclaimer: Information in this blog article has not been evaluated by the FDA. Arterosil is a branded nutraceutical. It and the information contained herein is not intended to diagnose, treat or cure any disease. As with all supplements, you should discuss use of this supplement with your physician.