An Updated Systematic Review of the Pharmacology of Silymarin

Abstract

Recent years have seen an explosion of scientific papers that deal with drugs from the fruits of milk thistle and its active substances silymarin (standardized mixture of flavonolignanes), thus justifying an updated systematic review. Methods: Electronic databases identified silymarin, silibinin, silicristin or milk thistle as descriptors in >700 papers (34% published in last 5 years; 92% dealt with animal pharmacological). Only papers adequately reporting on experimental conditions, dosing, variables tested and statistics were analysed. Results: Silymarin was found to modify specifically the functions related to various transporters and receptors located in the cell membranes; that is, organic anion uptake transporter peptides (OATP), ABC transporters (P-gp), bile salt export pump, as well as TNF-a-dependent and possibly selectin-dependent phenomena. In the cytoplasm, some antioxidant properties and the inhibition of the lipoxygenase pathway seem quite selective and could concur to the antitoxic effects. Some effects like the inhibition of inducible nitric-oxide synthase, of nuclear factor κ B, and reduction of collagen synthesis are indicative of DNA/RNAmediated effects. Several studies using ‘in vitro’ and ‘in vivo’ cancer models suggest a potential of silymarin in such diseases. Topical and systemic silymarin has skin protective properties against UV-induced damage in epidermis and causes an up-regulation of tumour-suppressor genes p53- and p21CIP1. There were no data on hepatic viral replication, viremia or spontaneous tumours in the data examined. Conclusions: Data presented here do not solve the question about the complex mechanism(s) of action of the medicinal herbal drug silymarin. Silymarin may be a natural multi-functional and multi-target drug.

Formulation of Microemulsion Systems for Dermal Delivery of Silymarin

“…To achieve skin benefits, effective amounts of silymarin require be solubilized and incorporated into the corresponding formulation. Due to poor water solubility (3.2 mg/100 mL) [6], the enhancement of silymarin solubility remains one of the most challenging aspects of drug development.…”

Silymarin Attenuated the Amyloid β Plaque Burden and Improved Behavioral Abnormalities in an Alzheimer’s Disease Mouse Model

“…13) Silymarin, the active ingredient of milk thistle extract, is a mixture of flavonolignane diastereomers: silibinin (silybin A þ silybin B) [(2R,3R)-3,5,7-trihydroxy-2-[(2R,3R)-3-(4-hydroxy-3-methoxyphenyl)-2-(hydroxymethyl)-2,3-dihydrobenzo[b] [1,4]dioxin-6-yl]chroman-4-one], isosilybin (isosilybin A þ isosilybin B), silydianin, and silychristin. 14,15) It has long been used as an anti-hepatotoxic agent without notable adverse effects, 16) especially against the damage caused by alcohol and disturbances in the function of the gastrointestinal tract, 17) but there have been no studies of the utility of silymarin in AD prevention. We suggest that if it has a preventive effect against the A-dependent phenotypes of AD, silymarin is a promising therapeutic agent for AD, since it has already been proven safe for human consumption.…”

A Review on the Role of Nutraceuticals as Simple as Se2+ to Complex Organic Molecules Such as Glycyrrhizin That Prevent as Well as Cure Diseases

“…Curcumin has been shown to inhibit the activation of NF-kB by inhibiting the phosphorylation and degradation of IkBa [58]. Silymarin, Silibinin release of cytochrome C from mitochondria, activation of caspases, increase of p53, mitochondrial membrane potential changes, G1 cell cycle arrest, G2/M arrest [59,60].…”