Effect Of Silybin Research Articles

Silybin Restored CYP3A Expression through the Sirtuin 2/Nuclear Factor κ-B Pathway in Mouse Nonalcoholic Fatty Liver Disease.

Silybin is widely used as a hepatoprotective agent in various liver disease therapies and has been previously identified as a CYP3A inhibitor. However, little is known about the effect of silybin on CYP3A and the regulatory mechanism during high-fat-diet (HFD)-induced liver inflammation. In our study, we found that silybin restored CYP3A expression and activity that were decreased by HFD and conditioned medium (CM) from palmitate-treated Kupffer cells. Moreover, silybin suppressed liver inflammation in HFD-fed mice and inhibited nuclear factor κ-B translocation into the nucleus through elevation of SIRT2 expression and promotion of p65 deacetylation. This effect was confirmed by overexpression of SIRT2, which suppressed p65 nuclear translocation and restored CYP3A transcription affected by CM. The hepatic NAD+ concentration markedly decreased in HFD-fed mice and CM-treated hepatocytes/HepG2 cells but increased after silybin treatment. Supplementing nicotinamide mononucleotide as an NAD+ donor inhibited p65 acetylation, decreased p65 nuclear translocation, and restored cyp3a transcription in both HepG2 cells and mouse hepatocytes. These results suggest that silybin regulates metabolic enzymes during liver inflammation by a mechanism related to the increase in NAD+ and SIRT2 levels. In addition, silybin enhanced the intracellular NAD+ concentration by decreasing poly-ADP ribosyl polymerase-1 expression. In summary, silybin increased NAD+ concentration, promoted SIRT2 expression, and lowered p65 acetylation both in vivo and in vitro, which supported the recovery of CYP3A expression. These findings indicate that the NAD+/SIRT2 pathway plays an important role in CYP3A regulation during nonalcoholic fatty liver disease. SIGNIFICANCE STATEMENT: This research revealed the differential regulation of CYP3A by silybin under physiological and fatty liver pathological conditions. In the treatment of nonalcoholic fatty liver disease, silybin restored, not inhibited, CYP3A expression and activity through the NAD+/ sirtuin 2 pathway in accordance with its anti-inflammatory effect.

Proteomics study on the effect of silybin on cardiomyopathy in obese mice

Due to the increase in the number of obese individuals, the incidence of obesity-related complications such as cardiovascular disease and type 2 diabetes is higher. The aim of the present study was to explore the effects of silybin on protein expression in obese mice. Firstly, serum was collected, and it was used to detect serum lipids and other serological indicators. Secondly, total protein from epididymal adipose tissue was extracted for differential expression analysis by quantitative tandem mass tag (TMT) combined with liquid chromatography-tandem mass spectrometry (LC–MS/MS), followed by bioinformatics and protein–protein interaction (PPI) network analyses of these proteins. Lastly, real-time polymerase chain reaction (RT-PCR) and parallel reaction monitoring (PRM) were used to further validate the expression of identified differentially expressed proteins (DEPs) at the mRNA and protein level, respectively. The results revealed that silybin could improve abnormal lipid metabolism caused by the high fat diet in obese mice. A total of 341, 538 and 243 DEPs were found in the high fat/control (WF/WC), silybin/high fat (WS/WF) and WS/WC groups, respectively. These DEPs mainly participated in lipid metabolism and energy metabolism. Notably, tropomyosin 1 (TPM1), myosin light chain 2 (MYL2), myosin heavy chain 11 (MYH11) and other DEPs were involved in hypertrophic cardiomyopathy, dilated cardiomyopathy and other pathways. Silybin could protect cardiac function by inducing the protein expression of TPM1, MYL2 and MYH11 in the adipose tissue of obese mice.

Silybin enhances the blood concentration of brexpiprazole in rats by downregulating expression of CYP3A4 and CYP2D6.

In this study, we investigated the effect of silybin on the pharmacokinetics of brexpiprazole and the underlying mechanism in rats. Two groups of animals received silybin at different doses (50 mg/kg, 25 mg/kg) for 2 weeks, while another group was given vehicle alone. After that, rats were intragastrically administrated with 2 mg/kg brexpiprazole. Then, the tail blood and liver tissues were collected from each rat at different time points. Brexpiprazole in serum was determined by an established UPLC-MS/MS assay. Finally, pharmacokinetic parameters of animals in each group were figured out. The results show that silybin remarkably changed the pharmacokinetic properties of brexpiprazole, especially at the highest dose. AUC and Cmax in the combination group with 50 mg/kg silybin were enhanced approximately 4 times as much as after a single dose of brexpiprazole, p < 0.05. Meanwhile, total liver protein of each sample was extracted, and was subjected to immunoblotting assay for probing CYP3A4 and CYP2D6. Therein CYP3A4 was significantly downregulated compared to the control group. Overall, silybin can increase blood concentration of brexpiprazole in rat by downregulating its main metabolic enzyme CYP3A4. Therefore, the maintenance dose of brexpiprazole should be decreased while co-treating with silybin.

Effects of silybin, flavonolignans, on catecholamine secretion and tyrosine hydroxylase activity in cultured bovine adrenal medullary cells

Effects of silybin, flavonolignans, on catecholamine secretion and tyrosine hydroxylase activity in cultured bovine adrenal medullary cells

Silybin Alleviates Hepatic Steatosis and Fibrosis in NASH Mice by Inhibiting Oxidative Stress and Involvement with the Nf-κB Pathway.

Silybin is the major biologically active compound of silymarin, the standardized extract of the milk thistle (Silybum marianum). Increasing numbers of studies have shown that silybin can improve nonalcoholic steatohepatitis (NASH) in animal models and patients; however, the mechanisms underlying silybin's actions remain unclear. Male C57BL/6 mice were fed a methionine-choline deficient (MCD) diet for 8weeks to induce the NASH model, and silybin was orally administered to the NASH mice. The effects of silybin on lipid accumulation, hepatic fibrosis, oxidative stress, inflammation-related gene expression and nuclear factor kappa B (NF-κB) activities were evaluated by biochemical analysis, immunohistochemistry, immunofluorescence, quantitative real-time PCR and western blot. Silybin treatment significantly alleviated hepatic steatosis, fibrosis and inflammation in MCD-induced NASH mice. Moreover, silybin inhibited HSC activation and hepatic apoptosis and prevented the formation of MDBs in the NASH liver. Additionally, silybin partly reversed the abnormal expression of lipid metabolism-related genes in NASH. Further study showed that the nuclear factor erythroid 2-related factor 2 (Nrf2) signaling pathway played important roles in the silybin-derived antioxidant effect, as evidenced by the upregulation of Nrf2 target genes in the silybin treatment group. In addition, silybin significantly downregulated the expression of inflammation-related genes and suppressed the activity of NF-κB signaling. Silybin was effective in preventing the MCD-induced increases in hepatic steatosis, fibrosis and inflammation. The effect was related to alteration of lipid metabolism-related gene expression, activation of the Nrf2 pathway and inhibition of the NF-κB signaling pathway in the NASH liver.

Molecular interaction of silybin with hyaluronidase: A spectroscopic and molecular docking study

ABSTRACTIn this study, the molecular interaction of silybin with hyaluronidase was investigated by spectroscopic methods and molecular docking. It was found that silybin had strong ability to quench the intrinsic fluorescence of hyaluronidase by a static quenching procedure. The binding constants were obtained at three temperatures (293, 298, and 310 K). The results of synchronous fluorescence and three-dimensional fluorescence and molecular docking showed that silybin bound into the hyaluronidase cavity site and the binding of silybin to hyaluronidase could induce micro-environmental and conformational changes in hyaluronidase, which resulted in the reduced hyaluronidase activity. The thermodynamic parameter analysis and molecular docking experiments revealed that all types of non-covalent interaction, including hydrogen bonding interaction, van der Waals forces, hydrophobic interaction, and electrostatic interaction were present in the binding process of silybin with hyaluronidase. The results obtained here will provide direct evidence at a molecular level to understand the mechanism of the inhibitory effect of silybin against hyaluronidase.

Effect of silybin in 1-methyl-4-phenyl-1,2,3,6 tetrahydropyridine (MPTP) induced parkinsonism in mice

Background: Parkinson disease (PD) is a major neurological disorder known since ancient times. Though drugs are available for therapy, still effective drug targeting the etiopathogenesis is always going on.Methods: After obtaining permission from animal ethics committee, the mice were divided into four groups of eight each (normal control, experimental control with normal diet only, silybin 300mg/kg, silybin 600mg/kg). At the end of 55 days the mice were subjected to overnight fasting followed by plasma and liver biochemical analysis.Results: The mice treated with 1-methyl-4-phenyl-1,2,3,6 tetrahydropyridine (MPTP) developed motor dysfunction and behavioural changes similar to PD, which was tested with rotarod test, photoactometer test and hang test which revealed the impaired performance, hypo-locomotion and impaired neuromuscular strength respectively. Treatment with silybin reversed the motor dysfunction significantly (p≤0.001) in a dose dependent manner. Biochemical analysis measured the oxidant (TBARS, SOD, CAT) and antioxidants (GPx and GSH) which revealed the oxidant activity of MPTP and antioxidant activity of silybin. Histopathological evaluation showed the cytoprotective effect of silybin.Conclusions: Silybin by its antioxidant property has a neuroprotective activity both in motor activity and behaviourally in the MPTP induced Parkinson disease in mice. Hence present study offers a conclusive evidence that silybin is a neuroprotective. Diet supplemented with silybin can protect against neurodegenerative disorders and prevent the progression of neurodegeneration.

PPARα MAY play a key role in the hepatoprotective effect of silybin against NASH

PPARα MAY play a key role in the hepatoprotective effect of silybin against NASH

Effect of silybin on the fibrillation of hen egg-white lysozyme.

In this study, the fibrillation of hen egg-white lysozyme (HEWL) in the absence and presence of different concentrations of silybin was studied by thioflavin T spectroscopy, Congo red binding assays, 8-anilino-1-naphthalenesulfonic acid (ANS) fluorescence assay, circular dichroism, and transmission electron microscopy. The experimental results indicated that not only the fibrillation of HEWL at high temperature (65°C) and low pH (pH=2.0) could be inhibited effectively by silybin but also the inhibition of HEWL by silybin followed a dose-dependent manner. Molecular docking studies indicated that 2 possible binding modes could be found in the interaction between silybin and HEWL via van der Waals forces and electrostatic forces as well as hydrogen bonding. One of these 2 conformations was directly entered into the cavity of HEWL (binding site I); the other was bound to the surface of HEWL (binding site II). In this way, silybin could not only increase the hydrophobicity of the cavity or the surface of HEWL but also influence the microenvironment of the binding site, which was able to stabilize the structure of HEWL and delay the process of HEWL fibrosis.

Liver-targeting self-assembled hyaluronic acid-glycyrrhetinic acid micelles enhance hepato-protective effect of silybin after oral administration

In order to enhance oral bioavailability and liver targeting delivery of silybin, two amphiphilic hyaluronic acid derivatives, hyaluronic acid-deoxycholic acid (HA-adh-DOCA) and hyaluronic acid-glycyrrhetinic acid (HA-adh-GA) conjugates, were designed and synthesized. Silybin was successfully loaded in HA-adh-DOCA and HA-adh-GA micelles with high drug-loading capacities (20.3% ± 0.5% and 20.6% ± 0.6%, respectively). The silybin-loaded micelles were spherical in shape with the average size around 130 nm. In vitro release study showed that two silybin-loaded micelles displayed similar steady continued-release pattern in simulated gastrointestinal fluids and PBS. Single-pass intestinal perfusion studies indicated that silybin-loaded micelles were absorbed in the whole intestine and transported via a passive diffusion mechanism. Compared with suspension formulation, silybin-loaded HA-adh-DOCA and HA-adh-GA micelles achieved significantly higher AUC and Cmax level. Moreover, liver targeting drug delivery of micelles was confirmed by in vivo imaging analysis. In comparison between the two micellar formulations, HA-adh-GA micelles possessed higher targeting capacity than HA-adh-DOCA micelles, owing to the active hepatic targeting properties of glycyrrhetinic acid. In the treatment of acute liver injury induced by CCl4, silybin-loaded HA-adh-GA micelles displayed better effects over suspension control and silybin-loaded HA-adh-DOCA micelles. Overall, pharmaceutical and pharmacological indicators suggested that the HA-adh-GA conjugates can be successfully utilized for liver targeting of orally administered therapeutics.

Investigation on the binding interaction between silybin and pepsin by spectral and molecular docking

In this study, the binding mode of silybin with pepsin was investigated by spectroscopic and molecular docking methods. Silybin can interact with pepsin to form a silybin–pepsin complex. The binding constant, number of binding sites and thermodynamic parameters were measured, which indicated that silybin could spontaneously bind with pepsin mainly through hydrophobic interaction with one binding site. Molecular docking results revealed that silybin bound into the pepsin cavity site. Synchronous fluorescence and three-dimensional fluorescence results provide data concerning conformational and some micro-environmental changes of pepsin. Furthermore, in order to reveal whether the binding process can inhibit the activity of pepsin in vivo, the effect of silybin on pepsin activity in rat was investigated. The present study provides direct evidence at a molecular level to show that exposure to silybin could induce changes in the enzyme pepsin structure and function.

F-49 A randomized multicentre double-blind vs placebo trial: Evaluation of effect of silybin conjugated with phosphatidilcholine and vitamin E on liver damage in patients with nonalcoholic fatty liver disease

F-49 A randomized multicentre double-blind vs placebo trial: Evaluation of effect of silybin conjugated with phosphatidilcholine and vitamin E on liver damage in patients with nonalcoholic fatty liver disease

The effect of silybin on passive avoidance learning and pathological changes in hippocampal CA1 and DG regions in male Wistar rats offspring

Silybin, an extract from seeds of milk thistle (Silybum marianum), is known to have hepato-protective, anticarcinogenic, and estrogenic effects. Given that estrogen effects on memory have been reported, silybin may cause structural changes in the hippocampal CA1 and dentate gyrus (DG) neurons and as a result it may enhance learning and memory. Wistar rats were provided with silybin (from day 7 of gestational age up to 4 weeks after birth) with 2 dosages of 18 mg/kg in the experimental group 1 (Exp1) and 9 mg/kg in the experimental group 2 (Exp2). Offspring memory retention was compared by duration of step-through latency in passive avoidance apparatus. Furthermore, histological changes were investigated in experimental groups and control group (CG). Both the experimental groups showed significantly longer step-through latency than CG (p < 0.001 for Exp1 and p < 0.01 for Exp2). The average number of pyramidal cells in hippocampal CA1 and granular cells in hippocampal DG was remarkably higher in Exp1 and Exp2 compared with CG. The difference was significant between Exp1 and Exp2 for pyramidal cells (p < 0.05) but not for granular cells. Silybin administration during pregnancy resulted in histological changes in hippocampus and better memory function. These data may lay the ground work using silybin in memory impairment diseases.

Effect of silybin and its glycosides on the expression of cytochromes P450 1A2 and 3A4 in primary cultures of human hepatocytes

Four beta-glycosides of flavonoligan silybin, i.e. silybin beta-galactoside, silybin beta-glucoside, silybin beta-maltoside, silybin beta-lactoside were synthesized in order to improve silybin water solubility and bioavailability (Kren et al., J Chem Soc, Perkin Trans 1, 2467-2474, 1997). The presented paper deals with the effect of silybin and its synthetic beta-glycosides on the expression of two major cytochrome P450 isoforms, CYP1A2 and CYP3A4. Primary cultures of human hepatocytes were the model of choice. mRNAs were analyzed using Northern blot and P-radiolabelled probes. CYP protein content was determined by immunoblotting using specific antibodies. Silybin and its beta-glycosides do not induce expression of CYP1A2 and CYP3A4. Tested compounds did not affect inducible expression of CYP1A2 and CYP3A4 by dioxin and rifampicin, respectively, as evaluated at the level of mRNAs and proteins. Silybin and its beta-glycosides do not interfere with the expression of CYP1A2 and CYP3A4, are not likely to produce drug-drug interactions in terms of the inducibility of two important cytochromes P450.

575 Effect of silybin and docetaxel on LNCap prostate cell growth and total PSA levels

575 Effect of silybin and docetaxel on LNCap prostate cell growth and total PSA levels

Effect of silybin on phorbol myristate actetate-induced protein kinase C translocation, NADPH oxidase activity and apoptosis in human neutrophils.

Mechanism of the action of silybin (1) and its derivatives (2-4), possessing different lipid solubility in PMA-stimulated neutrophils was evaluated. Silybin (1) inhibited the calcium, phosphatidylserine- and diacylglycerol-dependent protein kinase C translocation and the NADPH oxidase activity in PMA-stimulated neutrophils and resulted in decreased apoptosis. Furthermore, silybin (1) inhibited xanthine oxidase activity and hem-mediated oxidative degradation of low-density lipoprotein, as well. Its derivatives (2-4), possessing different lipid-solubility, affected all the studied parameters. The lipid solubility of silybin (1) was enhanced by methylation (5'7'4''trimethylsilybin: 2), whereas a decrease in lipid-solubility by acetylation of compound 2 (5',7,'4"-trimethylsilybin-acetate: 3) or all the hydroxyl groups of silybin (peracetyl-silybin: 4) attenuated the antioxidant capacity by decreasing the inhibition in PKC translocation and NADPH oxidase activation. All the derivatives of silybin (2-4) showed no inhibition in cell free systems; e.g. did not alter the xanthine oxidase activity and the hem-mediated oxidative degradation of LDL. In conclusion, the antioxidant activity of (1) might be due to its ability to inhibit PKC translocation and NADPH oxidase activation in PMA-stimulated neutrophils. The increase of lipid solubility of silybin (1) supports its penetration through cell membrane and enhances its inhibitory effects. This structural modification of (1) might have pharmacological consequences.

Effect of silybin and its congeners on human liver microsomal cytochrome P450 activities.

Silybin and related flavonolignans form a major part of the Silybum marianum extract, silymarin, which has been used to treat liver diseases for hundreds of years. Although regarded as safe, many of the extract constituents remain thus far untested for their possible effects on liver biotransformation enzymes. Cytochromes P450 (CYP) are very important in this regard. We tested the effect of four flavonolignans: silybin, its hemisynthetic derivative dehydrosilybin, silydianin, and silycristin on three specific CYP activities: bufuralol 1'-hydroxylation (CYP2D6), p-nitrophenol hydroxylation (CYP2E1), and nifedipine oxidation (CYP3A4). All flavonolignans displayed dose-dependent inhibition of these activities with IC(50) values in the micromolar range. The inhibition was competitive or mixed as revealed by double reciprocal plots of kinetic experiments. However, the inhibition is not considered to be relevant for therapy because physiological concentrations of the individual flavonolignans do not exceed 0.5 microM. The data support the use of the extract as a dietary supplement.

Iron-induced oxidant stress leads to irreversible mitochondrial dysfunctions and fibrosis in the liver of chronic iron-dosed gerbils. The effect of silybin.

Hepatic iron toxicity because of iron overload seems to be mediated by lipid peroxidation of biological membranes and the associated organelle dysfunctions. However, the basic mechanisms underlying this process in vivo are still little understood. Gerbils were dosed with weekly injections of iron-dextran alone or in combination with sylibin, a well-known antioxidant, by gavage for 8 weeks. A strict correlation was found between lipid peroxidation and the level of desferrioxamine chelatable iron pool. A consequent derangement in the mitochondrial energy-transducing capability, resulting from a reduction in the respiratory chain enzyme activities, occurred. These irreversible oxidative anomalies brought about a dramatic drop in tissue ATP level. The mitochondrial oxidative derangement was associated with the development of fibrosis in the hepatic tissue. Silybin administration significantly reduced both functional anomalies and the fibrotic process by chelating desferrioxamine chelatable iron.

Silybin decreases erythrocytic sorbitol level and improves peripheral nerve conduction velocity in patients with non-insulin dependent diabetes mellitus

The effects of silybin on erythrocytic sorbitol level and peripheral nerve conduction velocity were studied in 14 cases of non-insulin dependent diabetes mellitus (NIDDM). After oral administration of silybin 231 mg/day for 4 weeks, no blood glucose change was observed in patients with NIDDM, while the erythrocytic sorbitol level was significantly decreased from 72.55±21.61 to 39.53±14.94 nmol/g · Hb (P<0.01). At the same time, peripheral nerve conduction velocity was also improved. These results indicate that silybin is an effective aldose reductase inhibitor which can improve the disorder of polyol pathway in NIDDM patients and prevent chronic complications of diabetes.

Effects of silybin on histamine release from human basophil leucocytes

Effects of silybin on histamine release from human basophil leucocytes