Silymarin (Silybin B) (Silybin B) is a polyphenolic flavonoid that extracts from the milk thistle or seeds of Silybum marianum. It is used in the prevention and treatment of liver diseases.
Silibinin (Silybin) is the major active constituent of silymarin, a standardized extract of the milk thistle seeds, containing a mixture of flavonolignans consisting of silibinin, isosilibinin, silicristin, silidianin and others. Silibinin itself is a mixture of two diastereomers, silybin A and silybin 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.
Silydianin (Silidianin) exerts inhibition of UGT in human liver. Silydianin exerts inhibition of OATP1B1, OATP1B3 (unknown origin) expressed in HEK293 cells. Silydianin exerts inhibition of OATP2B1 (unknown origin) expressed in MDCK2 cells.
Isosilybin (Isosilibinin) and Silybin might be suitable candidates to design potent PXR antagonists to prevent drug-drug interactions via CYP3A4 in cancer patients.
Silychristin (Silicristin) is a plant growth regulator. Silychristin is an anti-hepatotoxic agent. Silychristin is the inhibitor of horseradish peroxidases and lipoxygenase.
Isosilybin A is a partial PPARγ agonist, it significantly induced ABCA1 protein expression, it inhibited both monophenolase (IC50=1.7-7.6μM) and diphenolase (IC50=12.1-44.9μM) of tyrosinase. Isosilybin A shows anti-angiogenic efficacy, it has anti-prostate cancer (PCA) activity that is mediated via cell cycle arrest and apoptosis induction.