Heart Awareness-The Endothelium
February is “Heart Awareness Month”, a perfect time to continue our series on maintaining a healthy heart. Part 3 of this series will focus on three herbs that have shown to support the structure and function of the cardiovascular system. (1)
When we look at the structure of the cardiovascular system, every vein and artery has a layer of cells called endothelial cells. This one-cell thick lining is known as the endothelium. And even though it’s only one-cell thick, the endothelium layer is extensive. In fact, if spread out, it would take up the area of 8 tennis courts! In larger vessels such as veins and arteries, the endothelium forms the blood vessel wall along with muscle cells and and elastic fibers. But, in capillaries, the endothelium is the entire blood vessel wall. One main job of the endothelium (one of many) is to provide a barrier between the blood and the rest of the body (2). However, substances (proteins, enzymes, gasses), must be allowed to come in and out of the endothelium, so it is really a selectivity permeable barrier. It also has a central role in the regulation of blood coagulation and it vascular tone and growth.
The endothelium can be damaged due to:
Poor nutrition, infections, physical trauma, as well as the secondary affects of stress contributing to hypertension, and atherosclerosis and insulin resistance.
So how can we protect our endothelium?
Clearly, proper nutrition is our first line of defense, as is finding ways to cope with stress. But if we turn to herbs (and spices), there are a number of them that can be very helpful.
Green tea (Camilla sinensis)
In 2007, a study found that catechins (or more specifically, epigallocatechin-3-gallate) in green tea were found to be helpful in reversing endothelial dysfunction associated with the arteries, but it was not just the catechins. (2) The authors go on to state that the believe it is the flavonoids found in the in green tea that also contributed to supporting the endothelial function. Now flavonoids can be found in dark berries, cacao nibs (and dark chocolate). So have a bowl of berries, a bar of chocolate, and a cup of green tea and support your endothelium and your heart!
Garlic (Allium sativum)
Garlic has so many wonderful attributes—you can just Google “garlic” and read about them. But did you know it also can help your heart—or more specifically the endothelium? Now most studies are not done on plants, but on extracts (including the green tea study). This is also true of garlic where many studies are done on aged garlic extract. Extracts are easier to administer and there is no variation in quality or potency of the plant, thus making them more ideal for studies. There was a study done in 2005 which found that that aged garlic extract did indeed have a positive effect on the endothelial function. This was a clinical trial done on men who had coronary heart disease. (3). They found that--yes, aged garlic was helpful; however, it wasn’t enough by itself to lower the risk in this population group. The take away is that it can be helpful but so is eating right and reducing stress.
With garlic, although it tastes better cooked, you will lose most of the herb’s health benefits eating it this way. Therefore, the best way to eat garlic is to smash it and let it sit for about ten minutes, then eat it raw. And then rinse your mouth out with a strong mouthwash! Of course, for taste, I love cooking with garlic.
Ginseng (Panax ginseng), also known as Korean ginseng, Chinese ginseng, Asian ginseng
Probably the biggest, ‘baddest’ herb in the study of herbal medicine is Panax ginseng; an herb that has been used in China for thousands of years as a tonic for aging. Good quality ginseng is extremely expensive, but for many people, it is indispensable and synonymous with good health. It is an adaptogen, meaning that it helps the body deal with stress, but it is so much more.
Here is the upshot of an important 2014 study: Korean Red Ginseng (KRG) supports the endothelium by actually helping to open the diameter of the blood vessel. Greater diameter = greater flow = lower blood pressure. (5)
Now the details. Normally, when processing ginseng, it is either dried or steamed. If steamed, it is known as Korean red ginseng (KRG). In the above mentioned study it was steamed. Before the 2014 study, there were several preclinical studies which examined ginseng's vasoprotective actions. Researchers wanted to figure out how ginseng worked. They concluded that it worked by enhancing nitric oxide (NO) synthesis in the endothelium—mainly the heart and lungs. The authors of the 2014 study wanted to take it to the next step and conduct a randomized, double-blind, crossover, controlled trial to see if ginseng really did have an effect on the endothelium. The two constituents they were looking at were: ginsenosides and polysaccharides. The study did indeed prove that KRG actually helped to open the diameter of the blood vessels. “Among the clinical implications of this trial is the vasodilatation potential of KRG during flow-stimulated conditions, thereby improving endothelial function, particularly for patients with cardiovascular disease. Endothelial dysfunction can contribute to atherogenesis preceding arterial plaque formation and increase future cardiovascular risk. Therefore ginseng may join the ranks of promising alternative agents that can affect endothelial function." Enough said!
In the next part we will look at herbs to keep our blood flowing. In the meantime, eat right and love big! Blessings, Jayne
(1) I originally said I was going to look at We will look at: plantain (Plantago major, lanceolata), calendula (Calendula officinalis) and Gotu kola (Centella asiatica), horse chestnut (Aesculus hippocastanum), and witch hazel (Hamamelis virginiana), but I am going to talk about these in answering some questions on the skin.
(2) If you are interested in a great tutorial on the endothelium, go to Marrta Toran’s lecture on “Endothelial cells: Function and explanation”. A video of this can be found at: https://study.com/academy/lesson/endothelial-cells-function-lesson-quiz.html
(3) Re: Epigallocatechin-3-gallate Found Effective in Reversing Endothelial Dysfunction; Widlansky ME, Hamburg NM, Anter E, et al. Acute EGCG supplementation reverses endothelial dysfunction in patients with coronary artery disease J Am Coll Nutr. Apr 2007;26(2):95-102.
(4) Re: Aged Garlic Extract Appears to Improve Endothelial Function in Men with Coronary Artery Disease; Williams M Sutherland W, McCormick M, Yeoman D, de Jong S. Aged garlic extract improves endothelial function in men with coronary artery disease Phytother Res. 2005;19:314-319
(5) Modulation of endothelial function by Korean red ginseng (Panax ginseng C.A. Meyer) and its components in healthy individuals: a randomized controlled trial. Jovanovski E, Peeva V, Sievenpiper JL, et al., Cardiovasc Ther. August 2014;32(4):163-169