Silibinin

Silibinin (INN), also known as silybin, is the major active constituent of silymarin, a standardized extract of the milk thistle seeds containing mixture of flavonolignans consisting of among others of silibinin, isosilibinin, silicristin and silidianin. Silibinin itself is mixture of two diastereomers silibinin A and silybinin B in approximately equimolar ratio. Both in vitro and animal research suggest that silibinin has hepatoprotective (antihepatotoxic) properties that protect liver cells against toxins. Silibinin has also demonstrated in vitro anti-cancer effects against human prostate adenocarcinoma cells, estrogen-dependent and -independent human breast carcinoma cells, human ectocervical carcinoma cells, human colon cancer cells, and both small and nonsmall human lung carcinoma cells.

Chemically modified silibinin, silibinin dihydrogen disuccinate disodium (trade name Legalon SIL) a solution for injection, is currently being tested as a treatment of severe intoxications with hepatotoxic substances, such as death cap (Amanita phalloides) poisoning. There is also clinical evidence for the use of silibinin as a supportive element in alcoholic and Child grade ‘A’ liver cirrhosis.