Silibinin is a suppressor of the metastasis-promoting transcription factor ID3.

BACKGROUND: ID3 (inhibitor of DNA binding/differentiation-3) is a transcription factor that enables metastasis by promoting stem cell-like properties in endothelial and tumor cells. The milk thistle flavonolignan silibinin is a phytochemical with anti-metastatic potential through largely unknown mechanisms. HYPOTHESIS/PURPOSE: We have mechanistically investigated the ability of silibinin to inhibit the aberrant activation of ID3 in brain endothelium and non-small cell lung cancer (NSCLC) models. METHODS: Bioinformatic analyses were performed to investigate the co-expression correlation between ID3 and bone morphogenic protein (BMP) ligands/BMP receptors (BMPRs) genes in NSCLC patient datasets. ID3 expression was assessed by immunoblotting and qRT-PCR. Luciferase reporter assays were used to evaluate the gene sequences targeted by silibinin to regulate ID3 transcription. In silico computational modeling and LanthaScreen TR-FRET kinase assays were used to characterize and validate the BMPR inhibitory activity of silibinin. Tumor tissues from NSCLC xenograft models treated with oral silibinin were used to evaluate the in vivo anti-ID3 effects of silibinin. RESULTS: Analysis of lung cancer patient datasets revealed a top-ranked positive association of ID3 with the BMP9 endothelial receptor ACVRL1/ALK1 and the BMP ligand BMP6. Silibinin treatment blocked the BMP9-induced activation of the ALK1-phospho-SMAD1/5-ID3 axis in brain endothelial cells. Constitutive, acquired, and adaptive expression of ID3 in NSCLC cells were all significantly downregulated in response to silibinin. Silibinin blocked ID3 transcription via BMP-responsive elements in ID3 gene enhancers. Silibinin inhibited the kinase activities of BMPRs in the micromolar range, with the lower IC50 values occurring against ACVRL1/ALK1 and BMPR2. In an in vivo NSCLC xenograft model, tumoral overexpression of ID3 was completely suppressed by systematically achievable oral doses of silibinin. CONCLUSIONS: ID3 is a largely undruggable metastasis-promoting transcription factor. Silibinin is a novel suppressor of ID3 that may be explored as a novel therapeutic approach to interfere with the metastatic dissemination capacity of NSCLC.

Use of Milk Thistle in Farm and Companion Animals: A Review.

Milk thistle, Silybum marianum, is a medicinal plant grown for its bioactive compounds with well-documented antioxidant and hepatoprotective properties. Milk thistle has a well-established pharmacological reputation for treatments of human liver disease, but it is also used in animals. This review summarizes the experimental evidence of milk thistle's effects on animals when administered as silymarin extract (feed additive) or a feed ingredient, if administered as seed or expeller/cake with the seed residue still containing the bioactive components. The use as a feed additive or feed ingredient is motivated by the complexity of silymarin registration as a veterinary drug. In farm animals, the drug improves the animals' performance and product quality and oxidative stability, supports liver function during the productive life-cycle, improves gut-health and morphology, and can reduce intestinal pathogens. In dogs and cats, the treatment is focused on acute and chronic liver diseases including the detoxification processes and support of drug treatments including chemotherapy. In equine athletes, milk seed cake showed positive effects and a faster return of cortisol to the resting values before exercise occurred. In aquaculture, it confirms its usefulness in supporting animal health and performance. In certain studies it is not clear what has been administered, and the composition and doses are not always clearly reported. A few studies reported no effects, but none reported problems connected to milk thistle administration. However, the overall picture shows that the use of milk thistle results in improved or restored health parameters or better animal performance.

Neural Network-based Optimization of Silybum Marianum Extract-loaded Chitosan Particles: Modeling, Preparation and Antioxidant Evaluation.

BACKGROUND: Silymarin is a flavonolignan extracted from Silybum marianum with various therapeutic applications. Many studies have focused on improving the bioavailability of silymarin due to its wide range of efficacy and low bioavailability. Chitosan, a naturally occurring polymeric substance, has a strong reputation for increasing the solubility of poorly soluble compounds. OBJECTIVE: This study used artificial neural networks (ANNs) to measure the effects of pH, chitosan to silymarin ratio, chitosan to tripolyphosphate ratio, and stirring time on the loading efficiency of silymarin into chitosan particles. METHODS: A model was developed to investigate the interactions between input factors and silymarin loading efficiency. The DPPH method was utilized to determine the antioxidant activity of an optimized formula and pure raw materials. RESULTS: According to the outcome of the ANN model, pH and the chitosan to silymarin ratio demonstrated significant effects on loading efficiency. In addition, increased stirring time decreased silymarin loading, whereas the chitosan-to-tripolyphosphate ratio showed a negligible effect on loading efficiency. CONCLUSION: Maximum loading efficiency occurred at a pH of approximately~5. Moreover, silymarin- loaded chitosan particles with a lower IC50 value (36.17 ± 0.02 ppm) than pure silymarin (165.04 ± 0.07 ppm) demonstrated greater antioxidant activity.

A computational approach to discover antioxidant and anti-inflammatory attributes of silymarin derived from Silybum marianum by comparison with hydroxytyrosol.

Medicinal plants possess therapeutic potential for reducing reactive oxygen species (ROS)-mediated cellular damage. Hydroxytyrosol is one of the most potent antioxidants that served as control in the current study, including other synthetic antioxidants to computationally identify the antioxidant properties of Silymarin. The sequences of the receptors IκB kinase (IKK), Kelch-like ECH-associated protein 1 (Keap-1) and mitochondrial transcription factor A (Tfam) were retrieved from UniProtKB and homology modeling was performed using Swiss-Model server. Thereof the molecular docking and dynamic simulation studies were performed using Schrödinger's software version 11.5. From the current study, it was reported that on comparison of the binding energy of silymarin, hydroxytyrosol, α-tocopherol, ascorbic acid, butylated hydroxy anisole (BHA) and butylated hydroxytoluene (BHT), Silymarin exhibited better affinities with IKK receptor followed by Hydroxytyrosol suggesting it as the best or comparable of all other known antioxidants that could potentially suppress inflammation and other diseases. Also, Silymarin exhibited poorest binding affinity with Tfam promoting mitochondrial biogenesis, thereby scavenging ROS. However, with Keap-1, Silymarin is ranked 4th in the list, whereas hydroxytyrosol exhibited highest binding affinity to release oxidative stress. The stability of docked complexes made us conclude that Silymarin has comparable antioxidant properties to hydroxytyrosol, better anti-inflammatory potential and mitochondrial biogenesis enhancing properties to ultimately reduce oxidative stress. Now it can be tested further for in vitro or in vivo studies as potential drug against oxidative insult.Communicated by Ramaswamy H. Sarma.

One-step sustainable extraction of Silymarin compounds of wild Algerian milk thistle (Silybum marianum) seeds using Gas Expanded Liquids.

This work reports the application of Gas Expanded Liquid (GXL) extraction to concentrate the flavonolignan fraction (silymarin) and taxifolin from Silybum marianum seeds, which have proven to be highly valuable health-promoting compounds. GXL using green solvents was used to isolate silymarin with the objective of replacing conventional methods. In one hand, the effect of different compositions of solvents, aqueous ethanol (20%, 50% or 80% (v/v)) at different CO2/liquid (25, 50 and 75%) ratios, on the GXL extraction was investigated. The obtained extracts have been chemically and functionally characterized by means of UHPLC-ESI-MS/MS (triple quadrupole) and in-vitro assays such as anti-inflammatory, anti-cholinergic and antioxidant. Results revealed that the operating conditions influenced the extraction yield, the total phenolic content and the presence of the target compounds. The best obtained yield was 55.97% using a ternary mixture of solvents composed of CO2:EtOH:H2O (25:60:15) at 40 °C and 9 MPa in 160 min. Furthermore, the results showed that obtained extracts had significant antioxidant and anti-inflammatory activities (with best IC50 value of 8.80 µg/mL and 28.52 µg/mL, respectively) but a moderate anti-cholinesterase activity (with best IC50 value of 125.09 µg/mL). Otherwise, the concentration of silymarin compounds in extract can go up to 59.6% using the present one-step extraction method without further purification, being silybinA+B the predominant identified compound, achieving value of 545.73 (mg silymarin/g of extract). The obtained results demonstrate the exceptional potential of GXL to extract high-added values molecules under sustainable conditions from different matrices.

Silybin and its congeners: from traditional medicine to molecular effects.

Covering: 2015 up to 2022 (Feb)Silymarin, an extract of milk thistle (Silybum marianum) fruits, has been used in various medicinal applications since ancient times. A major component of silymarin is the flavonolignan silybin and its relatives isosilybin, silychristin, silydianin, 2,3-dehydrosilybin, and some others. Except for silydianin, they occur in nature as two stereomers. This review focuses on recent developments in chemistry, biosynthesis, modern advanced analytical methods, and transformations of flavonolignans specifically reflecting their chirality. Recently described chemotypes of S. marianum, but also the newest findings regarding the pharmacokinetics, hepatoprotective, antiviral, neuroprotective, and cardioprotective activity, modulation of endocrine functions, modulation of multidrug resistance, and safety of flavonolignans are discussed. A growing number of studies show that the respective diastereomers of flavonolignans have significantly different activities in anisotropic biological systems. Moreover, it is now clear that flavonolignans do not act as antioxidants in vivo, but as specific ligands of biological targets and therefore their chirality is crucial. Many controversies often arise, mainly due to the non-standard composition of this phytopreparation, the use of various undefined mixtures, the misattribution of silymarin vs. silybin, and also the failure to consider the chemistry of the respective components of silymarin.

Effect of milk thistle (Silybum marianum) supplementation on the serum levels of oxidative stress markers in male half marathon athletes.

CONTEXT: Increased aerobic metabolism during exercise is a potential source of oxidative stress and the use of herbal medicines as a dietary supplement rich in antioxidants is an interesting and controversial concept that have been considered during the past decades. Objective: The purpose of the present study was to investigate the effects of Silybum marianum (SM) on exercise-induced oxidative stress in half marathon athletes. MATERIALS AND METHODS: Phytochemical Analysis in aqueous extract of SM leaves and seeds were determined. Forty healthy male athletes were divided into four groups (n = 10): control group(G1), G2 supplemented with 100 mg of SM leaves/kg/day, G3 supplemented with 100 mg of SM seeds/kg/day, and G4 supplemented with 100 mg of SM leaves + seeds/kg/day. The effects of SM on malondialdehyde (MDA) and antioxidant enzymes [superoxide dismutase (SOD), catalase (CAT), and glutathione (GSH)] were assessed. RESULTS: Aqueous extract of SM leaves have good DPPH free radical scavenging activity and the highest content of total polyphenols. A significant increase of serum SOD, CAT, and GSH levels and reduction in the levels of MDA in the serum of athletes supplemented with aqueous extract of seeds and leaves of SM was detected. CONCLUSION: SM supplement offered protection against exercise-induced oxidative stress.

Silybin B exerts protective effect on cisplatin-induced neurotoxicity by alleviating DNA damage and apoptosis.

ETHNOPHARMACOLOGICAL RELEVANCE: Silybum marianum is a traditional Chinese medicine that has been used for treating liver disease. Silybin consisting of silybin A and silybin B, is a member of Silybum marianum, and exerts a therapeutic effect on many diseases. However, the protective effect of silybin on cisplatin-induced neurotoxicity and the stereoisomer contributing to the effect remain unknown. AIM OF THE STUDY: The present study aimed to study the effect of silybin on cisplatin-induced neuronal injury, compare the difference of protective effect between silybin A and silybin B, and the potential mechanism. MATERIALS AND METHODS: High performance liquid chromatography (HPLC) was used to separate silybin A and silybin B. X-ray crystallographic analysis in combination with experimental and calculated ECD were performed to identify the structure of silybin A and silybin B. The toxicity of the silybin or cisplatin against murine hippocampal neuronal HT22 cells was determined through MTT assay. The cell cycle and cell apoptosis were measured by PI staining and Annexin V-FITC/PI staining, respectively, and then subjected to flow cytometry. Western blot analysis was conducted to quantify the expression of proteins related to apoptosis and DNA damage. Immunofluorescence was used to evaluate the expression of DNA damage marker. In vivo experiment, the behavioral analysis was determined through pole test, swimming test and Morris water maze test. The index of superoxide dismutase (SOD), reduced glutathione (GSH), total antioxidant capacity (T-AOC) and lipid peroxidation (LPO) were examined to evaluate the antioxidant capacity in mice brain. Nissl staining and Tunel assay were used to detect the neuronal viability and apoptosis in hippocampus. RESULTS: We successfully separated and identified silybin A and silybin B. We found both silybin A and silybin B alleviated cisplatin-induced apoptosis and cell cycle arrest in HT22 cells, and silybin B was more effective. We chose silybin B for further mechanism investigation, and found silybin B alleviated DNA damage by enhancing phosphorylation of ATR and decreasing expression of γ-H2AX. In the in vivo experiment, we observed that silybin B markedly improved the behavioral abnormalities in cisplatin-treated mice, reduced LPO level while increased SOD, GSH and T-AOC in mice brain tissue. Nissl staining and Tunel assay showed that silybin B alleviated cisplatin-induced hippocampal damage. CONCLUSIONS: These results suggest that silybin B might serve as a promising drug candidate in mitigating cisplatin-induced neural injury in the brain and thereby improving the chemotherapeutic outcomes.

System biology-based investigation of Silymarin to trace hepatoprotective effect.

Silymarin is used as a hepatoprotective agent since ancient times which could be via its potent anti-oxidant effect. However, the mode of silymarin for the hepatoprotective effect has not been established with the targets involved in hepatic cirrhosis. The present study investigated the multiple interactions of the flavonolignans from Silybum marianum with targets involved in hepatic cirrhosis using a series of system biology approaches. Chemo-informative tools and databases i.e. DIGEP-Pred and DisGeNET were used to predict the targets of flavonolignans and proteins involved in liver cirrhosis respectively. Further, STRING was used to enrich the protein-protein interaction for the flavonolignans-modulated targets. Similarly, molecular docking was performed using AutoDock Vina. Additionally, molecular dynamics simulation and MM-PBSA calculations were carried out for the lead-hit complexes by GROMACS. Thirteen flavonolignans were identified from S. marianum, in which silymonin exhibited the highest drug-likeness score i.e. 1.09. Similarly, CTNNB1 was found to be regulated by the 12 different flavonolignans and was majorly expressed within the compound(s)-protein(s)-pathway(s) network. Further, silymonin had the highest binding affinity; binding energy -9.2 kcal/mol with the CTNNB1 and formed very stable hydrogen bond interactions with Arg332, Ser336, Lys371, and Arg475 throughout 100 ns molecular dynamic production run. The binding free energy of CTNNB1-silymonin complex was found to be -15.83 ± 2.71 kcal/mol. The hepatoprotective property of S. marianum may be due to the presence of silymonin and silychristin; this could majorly modulate CTNNB1, HMOX1, and CASP8 in combination with other flavonolignans. Our findings further suggest designing the in-vitro and in-vivo studies to validate the interaction of flavonolignans with identified targets to strengthen present findings of S. marianum as a hepatoprotective..

Silybum marianum total extract, silymarin and silibinin abate hepatocarcinogenesis and hepatocellular carcinoma growth via modulation of the HGF/c-Met, Wnt/ß-catenin, and PI3K/Akt/mTOR signaling pathways.

Hepatocellular carcinoma (HCC) has been identified as one of the most deadly malignancies with limited therapeutic efficacy worldwide. However, understanding the molecular mechanisms of crosstalk between signaling pathways in HCC and predicting cancer cell responses to targeted therapeutic interventions remain to be challenge. Thus, in this study, we aimed to evaluate the anticancerous efficacy of Silybum marianum total extract (STE), silymarin (Sm), and silibinin (Sb) against experimentally-induced HCC in rats. In vitro investigations were also performed and the anticancer effects against HCC cell lines (HepG2 and Huh7) were confirmed. Wistar rats were given diethylnitrosamine (DEN)/2-acetylaminofluorene (AAF)/carbon tetrachloride (CCl4) and were orally treated with STE (200 mg/kg body weight (bw)), Sm (150 mg/kg bw), and Sb (5 mg/kg bw) every other day from the 1st or 16th week to the 25th week of DEN/AAF/CCl4 injection. Treatment with STE, Sm, and Sb inhibited the growth of cancerous lesions in DEN/AAF/CCl4-treated rats. This inhibition was associated with inhibition of Ki-67 expression and repression of HGF/cMet, Wnt/ß-catenin, and PI3K/Akt/mTOR signaling pathways. STE, Sm, and Sb improved liver function biomarkers and tumor markers (AFP, CEA, and CA19.9) and increased total protein and albumin levels in serum. STE, Sm, and Sb treatment was also noted to reduce the hepatic production of lipid peroxides, increase hepatic glutathione content, and induce the activities of hepatic antioxidant enzymes in DEN/AAF/CCl4-treated rats. These results indicate that STE, Sm, and Sb exert anti-HCC effects through multiple pathways, including suppression of Ki-67 expression and HGF/cMet, Wnt/ß-catenin, and PI3K/Akt/mTOR pathways and enhancement of antioxidant defense mechanisms.

Milk thistle (Silybum marianum (L.)Gaertn.): An overview about its pharmacology and medicinal uses with an emphasis on oral diseases.

BACKGROUND: Milk thistle, a medicinal plant, has different uses and benefits. Pathologies of the oral cavity manifest as different diseases with various therapeutic options. The main phytochemical extract of the milk thistle plant is silymarin. It has optimistic, protective, and therapeutic properties. However, evidence about the role of milk thistle extracts in oral diseases is lacking. HIGHLIGHT: The pharmacology of milk thistle was overviewed. The role of the plant in some systemic diseases was reviewed. Furthermore, its role in various oral diseases was discussed. The presented articles described such effects in the context of periodontal disease, dental caries, oral candidiasis, oral lichen planus, oral cancer, and oral mucositis. Results on the promising effects of milk thistle extracts with a preference for silymarin were presented from different research designs. A summary of the previously used doses and the currently available pharmaceutical products was proposed for future research. CONCLUSION: Milk thistle has antioxidant, anti-inflammatory, anticancer, antifungal, immunomodulatory, and other properties. The evidence from human research about the role of milk thistle in oral diseases is limited. Further studies, particularly clinical trials, to test milk thistle either as a potential treatment modality or a supplementary therapy for oral diseases on higher levels would be useful in the future.

Senotherapeutic-like effect of Silybum marianum flower extract revealed on human skin cells.

Cellular senescence causes irreversible growth arrest of cells. Prolonged accumulation of senescent cells in tissues leads to increased detrimental effects due to senescence associated secretory phenotype (SASP). Recent findings suggest that elimination of senescent cells has a beneficial effect on organismal aging and lifespan. In this study, using a validated replicative senescent human dermal fibroblasts (HDFs) model, we showed that elimination of senescent cells is possible through the activation of an apoptotic mechanism. We have shown in this replicative senescence model, that cell senescence is associated with DNA damage and cell cycle arrest (p21, p53 markers). We have shown that Silybum marianum flower extract (SMFE) is a safe and selective senolytic agent targeting only senescent cells. The elimination of the cells is induced through the activation of apoptotic pathway confirmed by annexin V/propidium iodide and caspase-3/PARP staining. Moreover, SMFE suppresses the expression of SASP factors such as IL-6 and MMP-1 in senescent HDFs. In a co-culture model of senescent and young fibroblasts, we demonstrated that senescent cells impaired the proliferative capacities of young cells. Interestingly, when the co-culture is treated with SMFE, the cell proliferation rate of young cells is increased due to the decrease of the senescent burden. Moreover, we demonstrated in vitro that senescent fibroblasts trigger senescent process in normal keratinocytes through a paracrine effect. Indeed, the conditioned medium of senescent HDFs treated with SMFE reduced the level of senescence-associated beta-galactosidase (SA-ß-Gal), p16INK4A and SASP factors in keratinocytes compared with CM of senescent HDFs. These results indicate that SMFE can prevent premature aging due to senescence and even reprograms aged skin. Indeed, thanks to its senolytic and senomorphic properties SMFE is a candidate for anti-senescence strategies.

Intestinal, liver and lipid disorders in genetically obese rats are more efficiently reduced by dietary milk thistle seeds than their oil.

We hypothesized that milk thistle seed or seed oil dietary supplementation reduces intestinal, liver and lipid disorders specific to genetic obesity, and the seeds can be more efficient in doing so. Lean and obese male Zucker rats were allocated to 4 groups: the lean (LC) and obese control (OC) groups fed a standard diet and the other 2 obese groups fed a diet supplemented with milk thistle seed oil (O + MTO) or milk thistle seeds (O + MTS). After 5 weeks of feeding, the cecal SCFA pool was slightly and significantly lower in OC and O + MTO compared with LC and O + MTS. The liver fat content was greater in OC, O + MTO and O + MTS compared with LC; however, it was significantly lower in O + MTS than in OC and O + MTO. The plasma cholesterol was greater in OC compared with LC, O + MTO and O + MTS; however, it was significantly greater in O + MTO and O + MTS compared with LC. The plasma bilirubin was detected in OC and O + MTO, whereas it was not present in LC and O + MTS. Milk thistle seeds can improve fermentation events in the distal intestine and reduce other disorders specific to genetically obese rats, and the seed PUFAs are responsible for that to a lesser extent.

Tackling of Renal Carcinogenesis in Wistar Rats by Silybum marianum Total Extract, Silymarin, and Silibinin via Modulation of Oxidative Stress, Apoptosis, Nrf2, PPARγ, NF-κB, and PI3K/Akt Signaling Pathways.

The present work was designed to assess the efficacy of Silybum marianum total extract (STE), silymarin (Sm), and silibinin (Sb) against experimentally induced renal carcinogenesis in male Wistar rats and their roles in regulating oxidative stress, inflammation, apoptosis, and carcinogenesis. The diethylnitrosamine (DEN)/2-acetylaminofluorene (AAF)/carbon tetrachloride (CCl4)-administered rats were orally treated with STE (200 mg/kg b.w.), Sm (150 mg/kg b.w.), and Sb (5 mg/kg b.w.) every other day either from the 1st week or from the 16th week of carcinogen administration to the end of 25th week. The treatments with STE, Sm, and Sb attenuated markers of toxicity in serum, decreased kidney lipid peroxidation (LPO), and significantly reinforced the renal antioxidant armory. The biochemical results were further confirmed by the histopathological alterations. The treatments also led to suppression of proinflammatory mediators such as NF-κß, p65, Iκßα, and IL-6 in association with inhibition of the PI3K/Akt pathway. Furthermore, they activated the expressions of PPARs, Nrf2, and IL-4 in addition to downregulation of apoptotic proteins p53 and caspase-3 and upregulation of antiapoptotic mediator Bcl-2. The obtained data supply potent proof for the efficacy of STE, Sm, and Sb to counteract renal carcinogenesis via alteration of varied molecular pathways.

Silymarin (milk thistle extract) as a therapeutic agent in gastrointestinal cancer.

Silymarin contains a group of closely-related flavonolignan compounds including silibinin, and is extracted from Silybum marianum species, also called milk thistle. Silymarin has been shown to protect the liver in both experimental models and clinical studies. The chemopreventive activity of silymarin has shown some efficacy against cancer both in vitro and in vivo. Silymarin can modulate apoptosis in vitro and survival in vivo, by interfering with the expression of cell cycle regulators and apoptosis-associated proteins. In addition to its anti-metastatic activity, silymarin has also been reported to exhibit anti-inflammatory activity. The chemoprotective effects of silymarin and silibinin (its major constituent) suggest they could be applied to reduce the side effects and increase the anti-cancer effects of chemotherapy and radiotherapy in various cancer types, especially in gastrointestinal cancers. This review examines the recent studies and summarizes the mechanistic pathways and down-stream targets of silymarin in the therapy of gastrointestinal cancer.

In-vitro evaluation of antiproliferative potential of various fractions of Silybum marianum using HeLa and HepG2 cell lines.

Silybum marianum (Milk thistle) has been proven to possess anticancer, lactogenic, neuroprotective, immunomodulatory, hepatoprotective and anti-inflammatory properties. The current study was designed to evaluate the antiproliferative potential of aqueous and various organic fractions (ethanolic, petroleum ether, ethyl acetate, chloroform, n-butanol) of S. marianum against cancerous [HeLa, HepG2] and noncancerous [BHK] cell lines. The MTT assay was performed to access the cytotoxicity of all these fractions and IC50 values were calculated. The cytotoxicity of these fractions was also confirmed through crystal violet and Trypan blue assays. All the tested fractions of S. marianum possessed significant antiproliferative potential. Interestingly, ethyl acetate fraction of S. marianum exhibited the highest antiproliferative activity amongst all the other tested fractions with an IC50 of 13.07 µg/ml, 18.92 µg/ml and 76.15µg/ml against HeLa, HepG2 and BHK cell lines respectively. So it is concluded that S. marianum possess strong anticancer activity against both cervical and liver cancer and low cytotoxicity against normal cell line so it could be used as a source of potent anticancer compounds having high efficacy and minimal side effects.

Nigella and Milk Thistle Seed Oils: Potential Cytoprotective Effects against 7ß-Hydroxycholesterol-Induced Toxicity on SH-SY5Y Cells.

Oxysterols are assumed to be the driving force behind numerous neurodegenerative diseases. In this work, we aimed to study the ability of 7ß-hydroxycholesterol (7ß-OHC) to trigger oxidative stress and cell death in human neuroblastoma cells (SH-SY5Y) then the capacity of Nigella sativa and Milk thistle seed oils (NSO and MTSO, respectively) to oppose 7ß-OHC-induced side effects. The impact of 7ß-OHC, associated or not with NSO or MTSO, was studied on different criteria: cell viability; redox status, and apoptosis. Oxidative stress was assessed through the intracellular reactive oxygen species (ROS) production, levels of enzymatic and non-enzymatic antioxidants, lipid, and protein oxidation products. Our results indicate that 7ß-OHC (40 µg/mL) exhibit pr-oxidative and pro-apoptotic activities shown by a decrease of the antioxidant enzymatic activities and an increase of ROS production, lipid, and protein oxidation end products as well as nitrotyrosine formation and caspase 3 activation. However, under the pre-treatment with NSO, and especially with MTSO (100 µg/mL), a marked attenuation of oxidative damages was observed. Our study suggests harmful effects of 7ß-OHC consisting of pro-oxidative, anti-proliferative, and pro-apoptotic activities that may contribute to neurodegeneration. NSO and especially MTSO showed potential cytoprotection against the cytotoxicity of 7ß-OHC.

Bioconversion of Callus-Produced Precursors to Silymarin Derivatives in Silybum marianum Leaves for the Production of Bioactive Compounds.

The present study aimed to investigate the enzymatic potential of Silybum marianum leaves to bioconvert phenolic acids produced in S. marianum callus into silymarin derivatives as chemopreventive agent. Here we demonstrate that despite the fact that leaves of S. marianum did not accumulate silymarin themselves, expanding leaves had the full capacity to convert di-caffeoylquinic acid to silymarin complex. This was proven by HPLC separations coupled with electrospray ionization mass spectrometry (ESI-MS) analysis. Soaking the leaf discs with S. marianum callus extract for different times revealed that silymarin derivatives had been formed at high yield after 16 h. Bioconverted products displayed the same retention time and the same mass spectra (MS or MS/MS) as standard silymarin. Bioconversion was achieved only when using leaves of a specific age, as both very young and old leaves failed to produce silymarin from callus extract. Only medium leaves had the metabolic capacity to convert callus components into silymarin. The results revealed higher activities of enzymes of the phenylpropanoid pathway in medium leaves than in young and old leaves. It is concluded that cotyledon-derived callus efficiently produces compounds that can be bio-converted to flavonolignans in leaves tissue of S. marianum.

Hepatic organic anion transporting polypeptides mediate disposition of milk thistle flavonolignans and pharmacokinetic silymarin-drug interactions.

Silybum marianum (L.) Gaertn. (Asteraceae), commonly known as milk thistle, is a botanical natural product used to self-treat multiple diseases such as Type 2 diabetes mellitus and nonalcoholic steatohepatitis (NASH). An extract from milk thistle seeds (achenes), termed silymarin, is comprised primarily of several flavonolignans. Systemic concentrations of these flavonolignans can influence the potential biologic effects of silymarin and the risk for pharmacokinetic silymarin-drug interactions. The aims of this research were to determine the roles of organic anion transporting polypeptides (OATPs/Oatps) in silymarin flavonolignan disposition and in pharmacokinetic silymarin-drug interactions. The seven major flavonolignans from silymarin were determined to be substrates for OATP1B1, OATP1B3, and OATP2B1. Sprague Dawley rats were fed either a control diet or a NASH-inducing diet and administered pitavastatin (OATP/Oatp probe substrate), followed by silymarin via oral gavage. Decreased protein expression of Oatp1b2 and Oatp1a4 in NASH animals increased flavonolignan area under the plasma concentration-time curve (AUC) and maximum plasma concentration. The combination of silymarin inhibition of Oatps and NASH-associated decrease in Oatp expression caused an additive increase in plasma pitavastatin AUC in the animals. These data indicate that OATPs/Oatps contribute to flavonolignan cellular uptake and mediate the interaction between silymarin and NASH on pitavastatin systemic exposure.

The effects of extraction techniques on the antioxidant potential of extracts of different parts of milk thistle (Silybum marianum L.).

BACKGROUND: Extracts of milk thistle, particularly from seeds, are used as a valuable source of natural antioxidants in different industries, for example pharmaceutical and cosmetic. The leaves and flowers are also known to be a source of biologically active compounds, as well as those with an antioxidant capacity. The selection of the extraction parameters, such as type and concentration of extractant, and extraction time, have an impact on the antioxidant capacity of the obtained extracts. The aim of this study was to evaluate the antioxidant activities of extracts obtained using different parts of raw material. The impact of different parameters of extraction on antioxidant capacity was also assessed. METHODS: The seeds, flowers and leaves were extracted using a Soxhlet apparatus, ultrasound and shaking. 96% (v/v) and 70% (v/v) ethanol, concentrated methanol, acetone and petroleum ether were applied as solvents. The impact of the extraction time was also evaluated. The extracts were evaluated using DPPH, ABTS, FRAP and Folin-Ciocalteu techniques. RESULTS: The obtained extracts, except for the samples in petroleum ether, showed the antioxidant capacity. Soxhlet extraction, especially that which uses ethanol, methanol and acetone, seems to be a valuable extraction method. CONCLUSIONS: To sum up, many factors could affect the antioxidant capacity and the total polyphenol content of Silybum marianum L. extracts. The solvent and an appropriately selected extraction method seem to be important factors in the effective isolation of active substances and could lead to the more effective application of this valuable plant material in different industries.