What Is Mu Tong
Mu Tong commonly known as Caulis Akebiae is the stem of Akebia quinata (Thunb.) Decne., A. trifoliata (Thunb.) Koidz., or A. trifoliata (Thunb.) Koidz. var. australis (Diels) Rehd., which is a twining woody vine belonging to the family Lardizabalaceae. It is a relatively practical and common Chinese herbal medicine, which first appeared in <Shennong Ben Cao Jing> in the late Western Han Dynasty (around 100 BCE).
There are 5 species of Akebia, which are mainly distributed in eastern Asia and eastern North America. Among them, Akebia quinata (Thunb.) Decne., A. trifoliata (Thunb.) Koidz., and A. trifoliata (Thunb.) Koidz. var. australis (Diels) Rehd are medicinal plants. Their stems, roots, and fruits are used medicinally.
Akebia quinata (Thunb.) Decne. commonly known as Chocolate vine, Five Leaf Akebia, or Five-leaf Chocolate Vine is deciduous to semi-evergreen vine. They prefer shade and humidity and are more cold-tolerant. They often grow in low-altitude hillsides, forests, and grasses. They grow well in slightly acidic, humus-rich yellow soil. They are found in China, Japan, North Korea, New Zealand, and the eastern United States.
A. trifoliata (Thunb.) Koidz. commonly known as Three Leaf Akebia is a deciduous woody vine. They often grow in sparse forests and thickets at an altitude of 250-2,000 meters. They are distributed in China and Japan.
A. trifoliata (Thunb.) Koidz. var. australis (Diels) Rehd is a subspecies of A. trifoliata (Thunb.) Koidz. They often grow in sloping thickets and sparse forests at an altitude of 300-2,100 meters. They are distributed in China and Japan.
In autumn, people gather the stems of Akebia quinata (Thunb.) Decne., A. trifoliata (Thunb.) Koidz., or A. trifoliata (Thunb.) Koidz. var. australis (Diels) Rehd., remove impurities and their twigs, soak them with water, cut them into pieces, dry them, and make them into Chinese herbal medicines.
Mu Tong contains akebiasaponin A~E, leonticin E, aradecoside D, ciwujianoside A1, ciwujianoside A2, scheffoleoside A, asiaticoside, guaianin N, aketrilignoside A, aketrilignoside B, oleanolic acid, ꞵ-sitosterol ꞵ-D-glucoside, aesculetin, caffeic acid, chlorogenic acid methyl, cryptochlorogenic acid methylester, methyl 3, 4-di-O-caffeoyl quinate, methyl 3, 5-di-O-caffeoyl quinate, methyl 4, 5-di-O-caffeoyl quinate, neochlorogenic acid methyl, vanillic acid, calceolarioside B, osmanthuside E, dunalianoside C, dunalianoside D, 2-(4-hydroxyphenyl)ethyl-(6-O-feruloyl)-β-D-glucopyranoside, 6,7,10-trihydroxy-8-octadecenoic acid, 4-hydroxy-3,5-dimethoxybenzenemethanol, stigmasterol, ꞵ-sitosterol, tetratriacontane, 2,6-dimethoxy-1,4-benzoquinone, lignans, saccharides, and proteins.
Generally, gray-brown or gray-brown Mu Tong with a yellowish-white cross-section and radial texture is preferred.
According to <Compendium of Materia Medica>, the medicinal nature of Mu Tong is relatively cold, with a bitter taste. It has a certain therapeutic effect on the pathological changes of the heart, small intestine, and bladder meridians.
In traditional Chinese medicine, it is often used to induce diuresis and relieve stranguria, clear heart-fire and relieve restlessness, stimulate the menstrual flow and lactation, and treat stranguria, scanty dark urine, edema, urinary tract infection, acute cystitis, aphtha, tongue sores, glossopyrosis, oral ulcer, acute pharyngitis, neuralgia, gastric ulcer, viral hepatitis, dysmenorrhea, menstrual disorders, abnormal leucorrhea, hypogalactia, insomnia, rheumatic arthralgia, indigestion, acute diarrhea, chronic abdominal pain, polycythemia vera, heart failure, cardiovascular diseases, and skin inflammations.
There are about 200 kinds of traditional Chinese medicine prescriptions containing it, such as Da Huang Qing Wei Wan, Long Dan Xie Gan Wan, and Fen Qing Wu Lin Wan.
Benefits
- Anti-inflammation, inhibiting xylene-induced ear swelling and carrageenan-induced paw swelling in mice.
- Increasing the pain threshold, decreasing the licking time of mice in the formalin test, delaying the reaction time of mice to the hot plate, and inhibiting acetic acid-induced writhing [1].
- Decreasing alanine transaminase activity and plasma ethanol concentration and alleviating alcohol hangover [2].
- Reducing alcohol-induced acute liver injury in mice and protecting the liver [3].
- Inducing diuresis and increasing urine output and Cl- excretion in rats.
- Treating edema, scanty dark urine, and stranguria caused by damp-heat in the urinary bladder.
- Clearing heart-fire and treating aphtha and tongue sores caused by flaming up of heart-fire.
- Purging heat in the small intestine and treating restlessness and brownish urine caused by a downward migration of heart-fire.
- Stimulating the menstrual flow and lactation, treating amenorrhea due to blood stasis, hypogalactia, and galactostasis.
- Its triterpenoids have certain inhibitory effects on Staphylococcus aureus, Bacillus thuringiensis, Escherichia coli, Salmonella enterica, and Shigella dysenteriae [4].
- Its alcoholic extract has an inhibitory effect on the proliferation of liver cancer SMMC-7721 cells, BEL-7404 cells, nasopharyngeal carcinoma CNE-1 cells, and gastric cancer SGC-7901 cells. Also, Its methanol extract can inhibit the activity of protein tyrosine phosphatase 1B and has a strong cytotoxic effect on breast cancer cell lines [5].
- Studies have found that Its ethanolic extract can inhibit lipid accumulation in 3T3-L1 fat cells and reduce the levels of intracellular triglycerides and free glycerol [6].
- Its extract ameliorated symptoms of stress-induced fatigue, including lethargic behaviors, and exerted a neuroprotective effect by regulating neurotransmitters and hormones through upregulation of BDNF/TrkB and CREB in mice exposed to chronic restraint stress [7].
Combinations
- It can be used in combination with Che Qian Zi (Semen Plantaginis), Hua Shi (Talcum), etc. to treat scanty dark urine and stranguria caused by damp-heat in the urinary bladder.
- It can be used in combination with Zhu Ling (Polyporus), Sang Bai Pi (Cortex Mori), etc. to treat edema.
- It can be used in combination with Sheng Di Huang (Radix Rehmanniae), Gan Cao (Licorice Root), Zhu Ye (Bamboo Leaf), etc. to treat restlessness and brownish urine caused by a downward migration of heart-fire.
- It can be used in combination with Hong Hua (Flos Carthami), Tao Ren (Semen Persicae), Dan Shen (Radix et Rhizoma Salviae Miltiorrhizae), etc. to treat amenorrhea due to blood stasis.
- It can be used in combination with Sang Zhi (Ramulus Mori), Yi Yi Ren (Semen Coicis), etc. to treat arthralgia caused by damp-heat.
Side Effects
- At present, there is no literature report that Mu Tong has toxic effects, and no data is showing that taking it at the prescribed dose can cause serious adverse reactions.
Precautions and Warnings
- The dosage of Mu Tong should be controlled at 3-6g.
- It can be made into decoctions, pills, powders, or lotions.
- People who are allergic to Mu Tong should not take it.
- It should not be used with medicines containing spironolactone.
- Patients without damp-heat syndrome should not take it.
- Patients with a deficiency of body fluid or spermatorrhea should not take it.
- Pregnant women should not take it.
- Breastfeeding women should take it under medical supervision.