Isosilybin

Isosilybin (Isosilybinin) is a flavonoid from milk thistle; inhibits CYP3A4 induction with an IC50 of 74 μM.

Product information

CAS Number: 72581-71-6

Molecular Weight: 482.44

Formula: C25H22O10

Chemical Name: 3,5,7-trihydroxy-2-[2-(4-hydroxy-3-methoxyphenyl)-3-(hydroxymethyl)-2,3-dihydro-1,4-benzodioxin-6-yl]-3,4-dihydro-2H-1-benzopyran-4-one

Smiles: COC1C=C(C=CC=1O)C1OC2C=CC(=CC=2OC1CO)C1OC2=CC(O)=CC(O)=C2C(=O)C1O

InChiKey: FDQAOULAVFHKBX-UHFFFAOYSA-N

InChi: InChI=1S/C25H22O10/c1-32-17-6-11(2-4-14(17)28)24-20(10-26)33-18-7-12(3-5-16(18)34-24)25-23(31)22(30)21-15(29)8-13(27)9-19(21)35-25/h2-9,20,23-29,31H,10H2,1H3

Technical Data

Appearance: Solid Power

Purity: ≥98% (or refer to the Certificate of Analysis)

Solubility: DMSO : 100 mg/mL (207.28 mM; Need ultrasonic).

Shipping Condition: Shipped under ambient temperature as non-hazardous chemical or refer to Certificate of Analysis

Storage Condition: Dry, dark and -20 ^oC for 1 year or refer to the Certificate of Analysis.

Shelf Life: ≥12 months if stored properly.

Stock Solution Storage: 0 - 4 ^oC for 1 month or refer to the Certificate of Analysis.

Drug Formulation: To be determined

HS Tariff Code: 382200

How to use

In Vitro:

The reporter gene assay shows that milk thistle’s components silybin and isosilybin are responsible for the inhibition of PXR-mediated CYP3A4 induction by milk thistle. Compared with silybin, its isomer isosilybin is a stronger inhibitor of PXR-mediated CYP3A4 induction. A solution of 89, 133, and 200 μM isosilybin significantly inhibits CYP3A4 induction by 64, 82, and 88%, respectively. Isosilybin inhibits CYP3A4 induction with an IC50 of 74 μM. Isosilybin B and isosilybin A, two diastereoisomers isolated from silymarin, have anti-prostate cancer (PCA) activity that is mediated via cell cycle arrest and apoptosis induction. Isosilybin B and isosilybin A treatment results in growth inhibition and cell death together with a strong G(1) arrest and apoptosis in human prostate cancer LNCaP and 22Rv1 cells. Isosilybin B causes increased phosphorylation of Akt (Ser-473 and Thr-308) and Mdm2 (Ser-166), which is linked with androgen receptor degradation as pretreatment with PI3K inhibitor (LY294002)-restored androgen receptor level. Isosilybin B treatment enhances the formation of complex between Akt, Mdm2 and AR, which promotes phosphorylation-dependent AR ubiquitination and its degradation by proteasome. Isosilybin A is able to significantly activate PPARγ at a concentration of 30 μM (2.08±0.48 fold, p<0.01). Isosilybin A causes transactivation of a PPARγ-dependent luciferase reporter in a concentration-dependent manner. In silico docking studies suggests a binding mode for 3 distinct from that of the inactive silymarin constituents, with one additional hydrogen bond to Ser342 in the entrance region of the ligand-binding domain of the receptor.

Products are for research use only. Not for human use.