Use of Licorice in the treatment of liver diseases
By Karina • May 9th, 2008 • Category: Liver Specific, shanghanlunThe Classic Text:
In the classic text Shanghanlun, there is record of prescriptions used to treat yellowing, otherwise known as jaundice or 黄疸. We’ll not cover the use of 茵陈蒿汤 and 麻黄连轺赤小豆汤 here, but will focus on 质子蘗皮汤. The original text:
“伤寒身黄发热，质子蘗皮汤主之。”
This presciption is made up of only three herbs: 质子，黄柏 and 甘草（licorice). If you know the herbs, then you’ll see the prescription as one predominantly combating the heat in the jaundice, and less the damp. Gardenia (质子) clears heat in the triple burner, while phellodendron (黄柏) clears the lower jiao and is also drying in nature. That said, licorice seems an unlikely member of the team. Textbooks will rationalize its use as one that “regulates the center” or “tonifies spleen weakness.” But we can look to biochemistry for an answer here.
Protecting The Liver:
Mice models with induced liver damage, when given licorice, show a fall in serum ALT levels. It reduces liver cell death rates; liver glycogen levels also improve. The usual suspects are glycyrrhizin (甘草甜素) and glycyrrhetinic acid (甘草次酸).
Corticoid-like effects:
Glycyrrhetinic acid (甘草次酸) is like a mineralo-corticoid in that it gets rid of potassium but keeps the water and sodium inside the body.
Glycyrrhizin (甘草甜素), on the other hand, behaves like a gluco-corticoid. 《中药药理学》 attributes such function to the following:
- facilitates production of glucocorticoids in the adrenals
- Glycyrrhetinic acid is very similar in structure to that of a glucocorticoid, so the latter is very easily convertable from the former
- Glycyrrhetinic acid inhibits the destruction of glucocorticoids in the liver, allow more to remain swimming in the bloodstream.
Immuno-strengthening:
Which includes:
- increased macrophage function
- Assist ConA in secreting gamma-INF
- Increases lymphocyte secretion of IL-2
and so on…