Hawthorn is a spiny bush or small tree that grows up to 7.5 m in height. Its deciduous leaves are divided into three to five lobes. The white, strong-smelling flowers grow in large bunches and bloom from April to June. The spherical bright red fruit contains one nut (C. monogyna) or two to three nuts (C. oxyacantha).1 Mor?phological and microscopical observation of certain Chi?nese hawthorn species has been performed.
The use of hawthorn dates back to Dioscorides, but the plant gained widespread popularity in European and American herbal medicine only toward the end of the 19th century. The flowers, leaves, and fruits have been used in the treatment of either high or low blood pressure, tachycardia, or arrhythmias. The plant is purported to have antispasmodic and sedative effects. Hawthorn has been used in the treatment of atheroscle?rosis and angina pectoris. Preparations containing haw?thorn remain popular in Europe4,5 and have gained some acceptance in the US.
The leaves, flowers, bark, and fruits con?tain the flavonoid pigments hyperoside and vitexin-rham?noside, leucoanthocyanidins, and the lactone crataegus?lactone (a mixture of ursolic, oleanic, and crataegolic acids). Flavonoid constituents from hawthorn have been frequently reported. Glycoflavonoid structural characteristics have been evaluated. Procyanidine and 2,3-cis-procyanidin have been isolated from haw?thorn. Chlorogenic acid from C. pyracantha Pers. has been found. Analysis of active hawthorn components has been reviewed.
Hawthorn's beneficial roles in car?diovascular disease have been extensively reviewed. Pharmacokinetic, pharmacodynamic, and metabolic studies on hawthorn have been performed.
Because of its strong cardiac activity, hawthorn has been suggested to be of use in CHF24,25 and cardiac perfor?mance. The plant is known to contain cardiotonic amines. The flavonoids cause an increase in coronary flow and heart rate and a positive inotropic effect. In isolated animal hearts, the inhibition of the enzyme 3' ,5'?cyclic adenosine menophosphate phosphodiesterase may be a mechanism by which hawthorn exerts its cardiac actions. When tested in rat cardiac myo hawthorn produced strong contraction of heart I along with increases in energy turnover in certe' cesses. Another study evaluated hawthorn in tion with digoxin to treat heart disease. At Ie, report exists on the plant's potential antiarrh' fects.
Hawthorn flavonoid components also possess vatory action. Extracts of hawthorn dilate bloodv~ in particular coronary blood vessels, resulting in r peripheral resistance and increased coronary circul In vitro increases in coronary circulation ranging 20% to 140% have been observed following the a istration of a dose equal to "'" 1 mg of the dry extrl Hawthorn also exhibited vasorelaxant effects in i rat mesenteric arteries. A double-blind study" related species C. pinnatifida and its effect on 46 cases has been performed.
Hawthorn is also known to be beneficial in myOC;1 ischemia. The flavonoid, monoacetyl-vitexinrhag side, possesses marked anti-ischemic properties in eral in vitro models, suggesting improvement in m~ dial perfusion. Hawthorn's effects on oxygen.de~ rat heart cells have been reported. The plant's infl on myocardial ischemia in dogs has also been e' ated. Other studies concerning circulation aSI have been addressed, including peripheral arterial ( lation disorder41 and varicose symptom complex.
Hawthorn has been studied in the prevention and I ment of atherosclerosis. A hawthorn preparation in, bination was administered to animals, resulting in I cholesterol, triglycerides, blood viscosity, and fibrin levels vs controls.
Another report finds tincture thorn to increase bile acid excretion and decrease lesterol synthesis in rats. The mechanism involvesJ up-regulation of hepatic LDL-receptors, resulting ~ greater influx of cholesterol into the liver. Hawthorn. also found to enhance cholesterol degradation. Adl containing hawthorn has lipid-lowering effects when' ied in rats and humans.
Hawthorn has been studied for its effects on hype sion. The plant has active components which vasorelaxation in rat mesenteric arteries.