Guest guest Posted December 1, 2003 Report Share Posted December 1, 2003 Hawthorne--By Michael T. Murray Key uses of Hawthorn: Angina Atherosclerosis Congestive heart failure High Blood pressure General Description Hawthorn (Crataegus oxyacantha) is a spiny tree or shrub that is native to Europe. The fruit and blossoms are used medicinally. Hawthorn leaves, berries, and blossoms contain many biological active flavonoid components, particularly anthocyanidins and proanthocyanidains. These flavonoids are responsible for the red-to-blue colors not only of Hawthorne berries but also of blackberries, cherries and blueberries,and grapes as well. These compounds are highly concentrated in hawthorn berry and flower extracts. High-performance liquid chromatography and thin-layer chromatography demonstrated that extracts of the flowers are particularly rich in flavonoids (quercetin, quercetin-3-galactoisde, vitexin, vitexin-4'- rhamnoside, etc.) and proanthocyanidins. In addition to flavonoids, hawthorn extracts also contain cardiotonic amines. (e.g.,phenylethylamine, 0-methoxyphenylethylamine, tyramine, and isobutylamine), choline and acetylcholine, purine derivatives (e.g. adenosine, adenine, guanine, and caffeic acid, amygdalin , pectins, and triterpene acids urolic, oleanolic, and crataegolic acids. History and Folk use- Hawthorn flowers and berries have been used primarily as heart tonics and mild diuretics in organic and functional heart disorders including congestive heart failure, angina, and high blood pressure. Pharmacology- The pharmacology of hawthorn centers on its flavonoid components, The proanthocyanidins in hawthorn are largely responsible for its cardiovascular activities. Synergism with Vitamin C- Hawthorn flavonoids have very strong " vitamin P " activity. Included in their effects are ability to increase intercellular vitamin C levels, stabilize vitamin C (by protecting it from destruction or oxidation), and decrease capillary permeability and fragility. Collagen-stabilizing action- Hawthorns flavonoid components possess significant collagen- stabilizing action. Collagen is the most abundant protein in the body and is responsible for maintaining the integrity of ground substance, tendons, ligaments, and cartilage. Anthocyanidins, proanthocyanidins, and other flavonoids are remarkable in their ability to prevent collagen destruction. They affect collagen metabolism in many ways, including: The unique ability to cross-link collagen fibers, resulting in reinforcement of the natural cross-linking of collagen that forms the collagen matrix of connective tissue (ground substance, cartilage, tendons,etc. The prevention of free radical damage, due to potent and free radicals scavenging action. The inhibition of enzymatic cleavage by enzymes secreted by white blood cells during inflammation. The prevention of the release and synthesis of compounds that promote inflammation, such as prostaglandins serine proteases, histamine, and leukotrines. Cardiovascular effects-- Hawthorn extracts are clinically effective in reducing blood pressure, angina attacks, and serum cholesterol levels and in preventing the *deposition* of *cholesterol* in arterial walls. The beneficial pharmacological effects of hawthorn in the treatment of these conditions appear to be a result of the following actions: Improvement of the blood supply to the heart by " dilating " the coronary vessels. Improvement of the metabolic processes in the heart, which results in an increase in the force of contraction of the heart muscle and elimination of some types of rhythm disturbances. Inhibition of angiotensin-converting enzyme- Hawthorns ability to dilate coronary blood vessels,the vessels supplying the heart with vital oxygen and nutrients, has been repeatedly *demonstrated* in experimental studies. This effect appears to be due to relaxation of the smooth muscle components of the vessel. Various flavonoid components in hawthorn have been shown to inhibit *constriction* of vessels by a variety of substances. When blood vessels constrict, blood pressure goes up. In addition, procyanidins have been shown to 'inhibit' angiotensin-converting enzyme. This enzyme is responsible for converting angiotensin l to angiotensin II, which is potent constrictor of blood vessels. Recently, several proanthocyanidins have demonstrated a specific inhibition of angiotensin-converting enzyme similar to that of captopril. Captropril is a synthetic angiotensin-converting enzyme inhibitor widely used in the treatment of high blood pressure. The proanthocyanidins that appear to have the highest activity are found in relatively high concentrations in Hawthorne berries, flowers and their extracts. Improvement in energy production within the heart has been demonstrated in humans and animals to whom Hawthorne extracts have been administered. The improvement is a result not only of increased blood and oxygen supply to the myocardium (muscle of the heart), but also a result of flavonoid-enzyme interactions. In particular, hawthorn extracts and various flavonoid components in hawthorn have been shown to inhibit several key enzymes within the myocardium (e.g. cyclic AMP phosphodiesterase). The net result is an increase in the force of contraction. This is particularly beneficial in cases of congestive heart failure (discussed below). A recent study has shed additional light on how Hawthorne extracts enhance heart function. A hawthorn extract standardized for proanthocyanidin content (3.3 percent) was studied utilizing an experimental model to determine the effects of a substance on heart function during " ischemia " . Although it's effectiveness in this model was different than that of beta-blockers and calcium channel blockers, two classes of drugs often used in treating angina, there are two distinctions to be made (1) the mechanism by which the drugs work in this model is by improving coronary blood flow and actually reducing the hearts need for oxygen by reducing its mechanical function. In contrast Hawthorne actually improves the mechanical function of the heart without " increasing " coronary blood flow. Evidence that Hawthorne improves energy metabolism and the utilization of oxygen by the heart was demonstrated by a decrease in accumulated lactic acid. Without oxygen, the heart muscle will shift to the breakdown of sugar for energy, but this can only go so far without oxygen. As a result, pyruvic acid is shunted to lactic acid. Recovery of heart function in inversely related to the level of lactic acid in the heart. The beneficial effects of hawthorn in angina appears to be related more to its ability to improve oxygen utilization, as noted by the reduction in heart tissue lactic acid levels, rather than to its ability to dilate coronary vessels. Atherosclerosis- Hawthorn extract, like other extracts containing proanthocyanidins (see chapter 18-Grape seed extract), although in a supplement form, should be thought of as a necessary food in the prevention and treatment of atherosclerosis. Increasing the intake of flavonoid compounds by taking hawthorn berry has numerous health-promoting effects, including " reducing " cholesterol levels and " decreasing " the *size* of existing " atherosclerotic " plaques. This again is a result of collagen stabilization. A *decrease* in the " integrity " of the collagen matrix of the artery *results* in " cholesterol " being " deposited " within the artery. Many researchers feel that if the collagen " matrix " remains strong, the atherosclerotic plaque will never *develop*. Hawthorn flavonoids, by increasing the integrity of collagen structures, may offer significant protection against atherosclerosis. In addition, feeding proanthocyanidin extracts to animals has resulted in the *reversal* of atherosclerotic " lesions " , as well as " decreases " in *serum cholesterol* levels. Flavonoids contained in hawthorn extracts appear to offer significant prevention, as well as potential *reversing* effects, in the treatment of athrerosclerotic processes, which are still the major causes of death in the United States. High Blood Pressure- Hawthorne exerts a mild blood-pressure-lowering effect that has been demonstrated in many experimental and clinical studies. Its action in lowering blood pressure in unique, in that it does so through a number of diverse pharmacological effects. Specifically, it " dilates " the coronary vessels, " inhibits " angiotensin-converting enzyme, increases the functional capacity of the heart, and possesses mild " diuretic " activity. Hawthorne's effects generally require prolonged administration, and in many instances take up to 2 weeks before adequate tissue concentrations are achieved. Dosage- The dosage depends on the type of preparation and source of material. Standardized extracts similar to those used in Europe and Asia as prescription medications, are available commercially in the U.S. and are the preferred forms to use for clinical purposes. The doses listed below for the various forms of hawthorn are for use three times a day. Hawthorne berries or flowers (dried): 3-5 grams or as an infusion Hawthorne tincture (1.5): 4-5 milliliters (alcohol may elicit pressor response in some individuals) Hawthorne fluid extract (1:1): 1-2 milliliters Hawthorne freeze-dried berries: 1-1.5 grams Hawthorne flower extract (standardized to contain 1.8 percent vitexin-4 rhamnoside or 20 percent procyanidins: 100-250 milligrams _________________ JoAnn Guest mrsjoguest DietaryTipsForHBP http://www.geocities.com/mrsjoguest/AIM.html Quote Link to comment Share on other sites More sharing options...
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