Japanese Folk Medicine
-Vol. 5 - Glechomae Herba- レンセンソウ（連銭草）-
Glechomae Herba (rensenso: 連銭草 in Japanese) is a dried entire plant from the flowering season of Glechoma hederacea L. var. grandis Kudo (kakidoshi: 垣通 in Japanese), which belongs to the Labiatae family. However, in China, rensenso is derived from the entire plant with or without root of the same genus of G. longituba Kupr., and it is also called kinsenso in the market.
G. hederacea var. grandis is a perennial herbaceous plant that grows on roadsides and the ground. It is native to Japan, Taiwan, the Korean Peninsula, China, and Eurasia. In general, 10 to 12 kinds of Glechma plants grow in the Temperate Zone of the Northern Hemisphere. It is 5 to 20 centimeters high, a fine hair covers the whole plant, and the stem is erect. As it grows, its branches extend transversely more than 50 centimeters and come out as roots in other places. Sometimes, the transversely extended branches stand up. The leaf has an opposing arrangement, with long petioles. It looks like a water lily's leaf and has a slim circular area, with a length of 15 to 25 millimeters. The leaves are soft, have wrinkles, and grow hair. The leaves are strongly scented when picked. The flower season is spring (April to May) and 2 to 3 light violet or red-violet labia form flowers which have spots on the axils of leaves.
The scientific name Glechoma is derived from the ancient Greek name glechon, which indicates a type of mint. Hederacea indicates the plant looks like a Hedera genus plant and grandis means large.
In Europe, Glechomae Herba is important as a folk medicine, and the medical literature from the 8th to 10th centuries describes it as a medicine for febrile illness. Herb tea which contains G. hederacea L. was likely widely consumed at that time. The English name 'ground ivy' or 'runaway robin' refers to short ivy which extends transversely, hugging the ground. 'Alehoof' derived from the plant is necessary for brewing, although the taste of beer between the 13th and 14th centuries was mainly a mixture of herb and spice.
The Japanese name rensenso refers to the crossover opposite leaf as is resembles money. Kakidoshi (垣通/籬通) originated as a stem being extended and entering through a fence from adjoining land, while kantoriso (疳取草) was used for a child's crying at night or for spasms. In addition, there are some idiomatic names, i.e., jishibari (地縛), zenikazura (銭葛), and tsuruhakka (蔓薄荷). In Japan, kakidoshi is one name for kantoriso and is used as a remedy for convulsions in children. The figure of kantoriso depicts with a crane and tortoise in a dish used babies' first meal, so kantoriso is basically a Japanese folk medicine that has been used in daily Japanese life.
The Chinese name is kakketsutan (活血丹) or kinsenso (金銭草), etc., and Chinese rensenso has many names for the crude drugs but the original plants are different, so often the original plants are confused.
The stem and leaf of G. hederacea var. grandis contains the essential oils l- pinocamphone, l- menthone, l- pulegone, α-, β-pinene, limonene, and linalool and amino acids of proline, methionine, tyrosine, and glutamic acid. It also contains tannin, ursolic acid, choline, β- sitosterol, and potassium nitrate, etc.
Pharmacological effects and toxicity
A noticeable diuretic effect was recognized when 20 g (crude drug) /kg of kinsenso decoction is injected into stomach of the rat. In addition, in anesthetized rabbits, a noticeable diuretic effect was recognized when 10 g (crude drug) /kg was injected into their stomachs. It is thought that the effect is caused by the action of potassium salt or ash. The diuretic effect is not recognized in tinctures. Although no choleretic action has been recognized in cats or rats, an excellent influence on diseases of the liver or gallbladder is said to be associated with free amino acids, i.e., methionine, cysteine, and serine.
The toxicity of kinsenso is extremely low, so rats did not die when 20 g (crude drug) /kg of decoction was injected into their stomachs for 6 days. In addition, there was no large effect on blood pressure when 100 g of decoction was injected into the stomach of a dog. Because kinsenso has been used as a medicinal plant or food product from ancient times, it is thought that there are no problems in terms of its safety for human beings.
Medicinal effects, dosage, and administration
The medicine is recorded in Bencaogangmu-shiyi (本草綱目拾遺) as follows: the essence is cool and sweet, and the medicine enters the liver, kidneys, and bladder. The medicinal effects are antipyretic, diuretic, healing, and antitussive, and the medicine is widely used as a decoction or medicinal tea for choloplania, edema, dysuria, urinary lithiasis, coughing, eczema, diabetes and convulsions in children.
In Japanese folk medicine, it has been known as a tonic for children with a weak constitution since ancient times. Kampo (Japanese traditional medicine) doctor of Tokuan Nagata wrote 'It is good for diarrhea to use this medicine as follows; a small amount of Geranium herb and licorice root are mixed with rensenso, decocted thickly, and then taken after warming.' The medicine was used to treat nervousness in children who were prone to convulsions, and used as an antipyretic and diuretic. For children with convulsions or a weak constitution, 6 to 10 g of rensenso is decocted and honey or a sweetener is added such to reduce bitterness, and given 3 times per day between meals.
The effects of rensenso are reported to be not only diuretic, lithagogue, and choleretic, but also increasing bile secretion. To treat calculus, 15 (g/day) of rensenso is decocted, and for choloplania or gallbladder calculus, 5 to 8 (g/day) of Artemisia capillaris flower is mixed, and for kidney and bladder calculus, 15 (g/ day) of Catalpa fruit is mixed. It is also good to add the same amount of Quercus salicina leaf. The medicine is also used for acute urethral inflammation with micturition pain, as well as difficulty of urination or choloplania (acute icterohepatitis) caused by heat and humidity. As for precautions for use, the medicine must be used for a long time for treat calculus. Generally, it takes more than one month. When the medicine is taken for a long time or in large doses, some patients feel lightheadedness or have palpitations, possibly related to egestion of potassium by diuresis. It is better to resupply adequate potassium salt or add astringent drugs (kojuyaku), i.e., Rosae Laevigatae Fructus (mature fruit of Rosa laevigata Michx. belonging to Rosaceae) or Euryales Semen (mature seed of Euryale ferox Salisb. belonging to Nymphaeaceae).
Furthermore, the medicine has an action to reduce blood sugar, so it is also known as a remedy for diabetes. For diabetes, 15g/day of plant is added to 600 mL of water and it is decocted until it is reduced by two-thirds. It is then taken 3 times per day, and it is taken for a long period. It is more effective when the same amount of Loquat leaf and Aralia elata stem are added. The medicine appears to have actions to decrease blood sugar and dissolve fat and calculus in the body, so it is used as a diet tea. Because the main compound of this plant is an essential oil, it also said that the medicine should not be decocted for a long time.
Because the fresh leaf has an anti-inflammatory effect, it is better to rub a fresh leaf repeatedly treat athlete's foot and tinea. For eczema and prickly heat, it is used as bath agent.
Recently, the medicine has been examined for its healing effect on hepatitis, urinary calculus, and gallstones in China, and sankinto (Glechomae Herba, Lygodii Spora, Gigeriae galli Endothelium corneum, Malvae Semen, Pyrrosiae Folium, Dianthi Herba) has been used for urinary calculus, while tandohaisekito (Glechomae Herba, Artemisiae Capillaris Flos, Curcumae Rhizoma, Gigeriae galli Endothelium corneum, corn silk, Aurantii Fructus Immaturus) has been used for cholelithiasis.
In China, it is also called kinsenso and is used the same way as in Japan. However, it is reported that there are some crude drugs derived from several original plants. For example, the branches and leaves of kinsenso (Desmodinm styracifolium Merr.) of the Fabaceae family are also used. Because the crude drug is widely used in Guangdong (Kanton in Japanese) province, it called kanton-kinsenso. The effects of kanton-kinsenso are the same as rensenso, and it is used as a specific medicine to treat urinary calculus and gallstones. Furthermore, it is used as a tea for diabetes and nephritis.
The Japanese folk medicine rensenso is basically kakidoshi. In quality, the best crude drug should be as follows; the color is green, it smells slightly of Mentha herb, the taste is distinctive, and the crude drug is new.
The main production area of this plant is Japan (Shikoku, Nagano pref.) and China (Huazhong, Huanan).
G. hederacea L. of a variegated species that is native to Europe is cultivated or sold under the name Glechoma (genus name of this plant) for gardening or ground cover because the plant is physically beautiful.
The entire plant is used for staining, and it stains brown color series, i.e., a yellow-brown color with aluminum or tin mordanting, a gray color with iron mordanting, and a dark brown color with copper mordanting.
Cultivation and collect of rensenso
The cultivation of rensenso is easy because it is a hardy plant. The plant likes sunny or semi-shaded, well-drained and moist soil. For breeding, planting seed in spring or division in autumn or spring is done. As for collection, the entire plant is mowed from around the root in the spring flowering season then cut off before drying it in the shade. To prevent foreign matter from getting into the crude drug, the dried plant is preserved in a closed container. It is preserved in an airy dark place, and care is taken tom control moisture and vermiculation.
F. Ikegami, Wakanyaku, 717, 9-10, (2013.2)