Crataegus oxyacantha is a thorny tree or shrub with white or red flowers and berries, known also as mayblossom and whitethorn, native of Europe. It is usually grown as a hedge plant, and in fact the name hawthorn is a corruption of hedgethorn. The plant’s berries and blossoms contain a large variety of flavonoids and other useful compounds.
The flavonoids include quercetin, quercetin-3-galactoside, vitexin, vitexin-4’-rhamnoside, and others, and a variety of proanthocyanidins. In addition to flavonoids, hawthorn also contains cardiotonic amines like phenylethylamine, o-methoxyphenylethylamine, tyramine, and isobutylamine, choline and acetylcholine, purine derivatives like adenine, adenosine, guanine and caffeic acid, amygdalin, pectins, and triterpenes like ursolic, oleanolic and crataegolic acids.
- Antioxidant. As it may be expected from the large number of flavonoids contained in hawthorn extracts, the herb possesses excellent antioxidant properties, including the ability to increase intracellular levels of vitamin C, stabilize its presence by protecting it from oxidation or destruction, and reducing capillary permeability and fragility.
- Blood pressure reducer. The herb is a clinically proven mild treatment for high blood pressure. Hawthorn’s action on hypertension is multifold. It has the ability to dilate the arteries and veins, it inhibits the angiotensin-converting enzyme, it increases the functional capacity of the heart, and possesses mild diuretic properties.
- Circulation tonic. Hawthorn is clinically proven to reduce blood pressure, attacks of angina, serum cholesterol levels, and the deposition of cholesterol on arterial walls. The herb does that through a number of actions. It augments the blood supply to the heart by dilating the coronary vessels. It improves the metabolic processes of the heart, increasing the force of contraction and eliminating some arrhythmias. Finally, it inhibits the production of the enzyme that converts angiotensin I to angiotensin II, that is the process of potentiating a powerful blood vessel constrictor.
- Collagen stabilizer. The herb’s flavonoids possess notable collagen-stabilizing properties. Collagen is destroyed during inflammation, which may involve the skin, bones, joints, cartilage, and other connective tissue as it happens with rheumatoid arthritis for example. Hawthorn’s flavonoids beneficially affect collagen metabolism by cross-linking collagen fibers and increasing the collagen matrix resilience; preventing free radical damage by powerful scavenging action; inhibiting enzymatic cleavage by the enzymes secreted by white blood cells during inflammation; and by blocking the formation and release of compounds promoting inflammation, such as prostaglandins, histamine, serine proteases and leukotrienes.
- Heart tonic. Hawthorn demonstrably improves the heart’s energy production capacity. This is partly due to increased blood and oxygen supply to the heart muscle, and partly by inhibiting several key enzymes within the myocardium, such as cyclic AMP phosphodiesterase, and others. The result is an increase in the force of contraction. A study comparing a hawthorn extract with beta-blockers and calcium channel blockers, two classes of chemical drugs often used to treat angina, has cast some light on the different processes involved. The drugs also increase coronary blood flow, but reduce the heart’s oxygen needs by lowering its mechanical function. Hawthorn on the other hand improved heart function even without increasing coronary blood flow. In other words hawthorn improves energy metabolism and the heart’s ability to utilize oxygen.