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1.
Molecules ; 24(20)2019 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-31615114

RESUMO

Silymarin, the extract of milk thistle, and its major active flavonolignan silybin, are common products widely used in the phytotherapy of liver diseases. They also have promising effects in protecting the pancreas, kidney, myocardium, and the central nervous system. However, inconsistent results are noted in the different clinical studies due to the low bioavailability of silymarin. Extensive studies were conducted to explore the metabolism and transport of silymarin/silybin as well as the impact of its consumption on the pharmacokinetics of other clinical drugs. Here, we aimed to summarize and highlight the current knowledge of the metabolism and transport of silymarin. It was concluded that the major efflux transporters of silybin are multidrug resistance-associated protein (MRP2) and breast cancer resistance protein (BCRP) based on results from the transporter-overexpressing cell lines and MRP2-deficient (TR-) rats. Nevertheless, compounds that inhibit the efflux transporters MRP2 and BCRP can enhance the absorption and activity of silybin. Although silymarin does inhibit certain drug-metabolizing enzymes and drug transporters, such effects are unlikely to manifest in clinical settings. Overall, silymarin is a safe and well-tolerated phytomedicine.


Assuntos
Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/genética , Hepatopatias/tratamento farmacológico , Proteínas Associadas à Resistência a Múltiplos Medicamentos/genética , Proteínas de Neoplasias/genética , Silimarina/uso terapêutico , Animais , Antioxidantes , Flavonolignanos/metabolismo , Humanos , Hepatopatias/genética , Hepatopatias/patologia , Cardo Mariano/química , Fitoterapia , Ratos , Silibina/metabolismo
2.
AAPS PharmSciTech ; 20(7): 293, 2019 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-31432294

RESUMO

In this study, a novel human serum albumin nanoparticle loading silybin-phospholipid complex (SLNPs) was developed for liver targeting after intravenous administration. The preparation of the drug delivery system consisted of two steps; initially, a silybin-phospholipid complex (SLC) was produced to improve the lipophilicity of SLB to then achieve enhanced encapsulation of SLB in albumin nanoparticles. FT-IR and XRD analysis confirmed the successful formation of SLC. The complex ratio of SLC in the first step was 99.6%. The encapsulation efficiency and drug loading of SLNPs in the second step were 96.2% and 5.6%, respectively. SLNPs were spherical and well-dispersed, with a zeta potential of approximately - 10 mV, and a mean particle size around 200 nm. An in vivo tissue distribution experiment and a pharmacodynamic experiment showed that, compared with SLB solution, SLNPs had an improved SLB accumulation in the liver. The hepatoprotective effect of SLNPs on CCl4-induced acute liver damage was evaluated. CCl4-damaged mice showed an increased enzymatic activity of ALT and AST; however, enzyme levels returned to near-normal levels in high-dose SLNP-treated mice. As SLNPs combine the enhanced oil solubility of SLC and the passive targeting of albumin nanoparticles, they possess great potential for the treatment of acute liver damage.


Assuntos
Albuminas/química , Hepatopatias/tratamento farmacológico , Fosfolipídeos/química , Silibina/química , Administração Intravenosa , Animais , Sistemas de Liberação de Medicamentos , Humanos , Camundongos , Nanopartículas/administração & dosagem , Tamanho da Partícula , Ratos , Ratos Sprague-Dawley , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier , Distribuição Tecidual
3.
Pathol Res Pract ; 215(9): 152530, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31351801

RESUMO

BACKGROUND: Previous investigation have indicated Silibinin induces apoptosis and JNK/SAPK in human pancreatic cancer cells. This study aims to evaluate the further mechanism of Silibinin in pancreatic cancer treatment. MATERIALS AND METHODS: Human pancreatic cancer cell lines SW1990 was treated with Silibinin and/or JNK/SAPK inhibitor SP600125 followed by measurement of cell viability, apoptosis, autophagy, ROS and ATP, and western blotting. RESULTS: Silibinin promoted cell viability and promoted cell apoptosis. The expression of ROS and ATP associated with mitochondrial function was also promoted by the treatment of silibinin. Silibinin also promoted autophagy in pancreatic cancer cells. All these biological effects of Silibinin can be reversed by JNK/SAPK inhibitor. CONCLUSIONS: The biological effects regulated by Silibinin can be mediated by JNK/SAPK signaling. This provides a solid theoretical basis for the role of Silibinin in the treatment of pancreatic cancer.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Neoplasias Pancreáticas/patologia , Silibina/farmacologia , Autofagia/efeitos dos fármacos , Linhagem Celular Tumoral , Humanos , MAP Quinase Quinase 4/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos
4.
Mol Cell Biochem ; 460(1-2): 81-92, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31183735

RESUMO

High levels of circulating free fatty acids often trigger pancreatic ß cell dysfunction during the development of type 2 diabetes. Silibinin, the main component of Silybum marianum fruit extract (silymarin), is reported to have anti-diabetic effect. This study is designed to determine the protective effect of silibinin on palmitic acid-induced damage in a rat pancreatic ß-cell line, INS-1 cells. Our results demonstrate that silibinin improves cell viability, enhances insulin synthesis and secretion, and resumes normal mitochondrial function in palmitic acid-treated INS-1 cells. An accumulating body of evidence has shown that the estrogen receptors are key molecules involved in glucose and lipid metabolism. Our results suggest that silibinin upregulates ERα signaling pathway from the finding that ERα-specific inhibitors abolish the anti-lipotoxic effect of silibinin. In conclusion, these findings suggest that silibinin protects INS-1 cells against apoptosis and mitochondrial damage through upregulation of ERα pathway.


Assuntos
Apoptose/efeitos dos fármacos , Receptor alfa de Estrogênio/metabolismo , Células Secretoras de Insulina/metabolismo , Células Secretoras de Insulina/patologia , Mitocôndrias/patologia , Ácido Palmítico/toxicidade , Silibina/farmacologia , Animais , Linhagem Celular Tumoral , Citoproteção/efeitos dos fármacos , Células Secretoras de Insulina/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Substâncias Protetoras/farmacologia , Ratos , Silibina/química , Regulação para Cima/efeitos dos fármacos
5.
Appl Microbiol Biotechnol ; 103(17): 7141-7149, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31236617

RESUMO

The newly reported associations between Alzheimer's disease (AD) and gut microbiota indicate the potential of gut microbiota regulation-based therapeutic intervention for AD. Silymarin and its main active component, silibinin, are promising natural agents against AD, while their acting mechanisms remain to be explored. The present study investigated the effects of silibinin and silymarin administration on behavioral and histological manifestations, and regulation on the gut microbiota of transgenic APP/PS1 mice. First, silibinin and silymarin administration could alleviate memory deficits and reduce the amyloid plaque burden in the brain of APP/PS1 mice in comparison with controls. Second, silibinin and silymarin administration tended to decrease the microbiota diversity and exhibited regulative effect in abundances on several key bacterial species associated with AD development. This implied that gut microbiota regulation by silibinin and silymarin might be involved in their effects against AD. Further studies are warranted to fully elucidate the molecular mechanisms.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Antioxidantes/uso terapêutico , Microbioma Gastrointestinal/efeitos dos fármacos , Silibina/uso terapêutico , Silimarina/uso terapêutico , Doença de Alzheimer/microbiologia , Doença de Alzheimer/patologia , Doença de Alzheimer/psicologia , Animais , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Biodiversidade , Modelos Animais de Doenças , Hipocampo/metabolismo , Aprendizagem/efeitos dos fármacos , Masculino , Camundongos , Camundongos Transgênicos , Placa Amiloide/metabolismo
6.
Eur J Pharm Sci ; 137: 104969, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31238095

RESUMO

The current study developed an innovative Pemulen® TR2 hydrogel containing silibinin-loaded pomegranate oil-based nanocapsules (HP-NC SB) intending cutaneous application. The formulation anti-inflammatory activity in an in vivo model and biometric studies on the skin of healthy volunteers were also performed. The nanocapsules were prepared using the interfacial deposition of preformed polymer technique and the hydrogels were obtained by thickening of nanocapsules suspension with Pemulen® TR2. Formulations with free compound, vehicle and blank nanocapsules were also produced. The hydrogels were evaluated concerning pH, silibinin content, particle size, spreadability profile, rheology, in vitro drug release, cutaneous permeation, bioadhesive potential and cutaneous biometry evaluation. Furthermore, a model of contact dermatitis croton oil-induced in mice was performed to evaluate the hydrogels anti-inflammatory potential. The formulations presented adequate characteristics for skin administration: particle within nanometric size, pH values in the acid range, silibinin content close theoretical values (1 mg/g) and non-Newtonian pseudoplastic behavior. Nano-based hydrogels showed high bioadhesive properties, increased silibinin in vitro release profile and its retention in the stratum corneum. The best anti-inflammatory effect was exhibited by HP-NC SB, which reduced both ear edema and inflammatory cells infiltration in comparison to the induced group. Furthermore, cutaneous biometric evaluation showed that formulations containing free or nanoencapsulated silibinin caused no modification in normal skin conditions (pH, tissue hydration, transepidermal water loss and erythema). In summary, the results demonstrated that the Pemulen® TR2 hydrogel containing NC SB was successfully developed, indicating its potential as an alternative treatment for irritant contact dermatitis.


Assuntos
Anti-Inflamatórios/administração & dosagem , Dermatite de Contato/tratamento farmacológico , Edema/tratamento farmacológico , Hidrogéis/administração & dosagem , Nanocápsulas/administração & dosagem , Silibina/administração & dosagem , Administração Cutânea , Animais , Anti-Inflamatórios/química , Óleo de Cróton , Liberação Controlada de Fármacos , Feminino , Humanos , Hidrogéis/química , Irritantes , Masculino , Camundongos , Nanocápsulas/química , Silibina/química , Absorção Cutânea
7.
Food Chem Toxicol ; 132: 110645, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31254591

RESUMO

The flavonolignan silibinin is the major component of the extract isolated from the seeds of the milk thistle (Silybum marianum). Herein, we performed an in silico analysis focusing on the molecular docking of the putative atomic interactions between silibinin and heat shock protein 90 (Hsp90), an adenosine triphosphate-dependent molecular chaperone differentially expressed in response to microenvironmental stress. Time-resolved fluorescence resonance energy transfer was employed to measure the capacity of silibinin to inhibit Hsp90 binding to other co-chaperones with enzymatic activity. Whereas silibinin is predicted to interact with several pockets in the C-terminal domain (CTD) of Hsp90α and ß, its highest-ranking docked poses significantly overlap with those of novobiocin, a well-characterized Hsp90 CTD-targeting inhibitor. The net biochemical effect of silibinin was to inhibit the efficiency of Hsp90α/ß CTD binding to its co-chaperone PPID/cyclophilin D in the low millimolar range, equivalent to that observed for novobiocin. The hepatotoxicant behavior of silibinin solely occurred at concentrations several thousand times higher than those of the Hsp90 N-terminal inhibitor geldanamycin. Silibinin might be viewed as a non-hepatotoxic, novobiocin-like Hsp90 inhibitor that binds the CTD to induce changes in Hsp90 conformation and alter Hsp90-co-chaperone-client interactions, thereby providing new paths to developing safe and efficacious Hsp90 inhibitors.


Assuntos
Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Proteínas de Choque Térmico HSP90/metabolismo , Silibina/metabolismo , Silibina/farmacologia , Antineoplásicos/química , Antineoplásicos/metabolismo , Antineoplásicos/farmacologia , Sítios de Ligação , Ciclofilinas/metabolismo , Proteínas de Choque Térmico HSP90/química , Células Hep G2 , Humanos , Simulação de Acoplamento Molecular , Novobiocina/química , Novobiocina/metabolismo , Ligação Proteica , Multimerização Proteica/efeitos dos fármacos , Silibina/química , Superóxidos/metabolismo
8.
Molecules ; 24(11)2019 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-31185663

RESUMO

Silybin (SBN) is a major active constituent of silymarin, a mixture of flavonoids found in fruits and seeds of milk thistle. The aim of this study was to describe a simple bioanalytical method for quantifying SBN in rat plasma. A simple protein deproteinization procedure with acetonitrile (ACN) was employed for plasma sample preparation. A reversed column and gradient elution of a mobile phase (mixture of phosphate buffer (pH 5.0) and ACN) were used for chromatographic separation. The selectivity, linearity (50-5000 ng/mL), precision, accuracy, recovery, matrix effect, and stability for this method were validated as per the current Food and Drug Administration (FDA) guidelines. Our method for SBN was applied to a comparative pharmacokinetic study on four different commercial silymarin products. This in vivo rat study demonstrated that product #4 significantly enhanced the relative oral bioavailability of SBN, as compared to product #1-3. Therefore, the bioanalytical method proposed herein could serve as a promising alternative for preclinical pharmacokinetic studies on silymarin products and, by extension, clinical use after partial modification and validation.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Silibina/sangue , Silibina/farmacocinética , Administração Oral , Animais , Masculino , Ratos Sprague-Dawley , Padrões de Referência , Silibina/administração & dosagem , Silibina/química , Fatores de Tempo
9.
Int J Mol Med ; 44(2): 705-712, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31173180

RESUMO

Overconsumption of fats and sugars is a major cause of development of non­alcoholic fatty liver disease (NAFLD). The main objectives of the present study were to explore the pathways sustaining the interfering metabolic effects of excess fructose and fatty acids in hepatocytes, and to clarify the mechanisms through which the nutraceutical silybin rescues the functional and metabolic alterations that are associated with the NALFD progression. Cultured hepatocytes were exposed to fructose and fatty acids, alone or in combination, to induce different grades of steatosis in vitro. Cell viability, apoptosis, free radical production, lipid content, lipid peroxidation and activity of lipogenic enzymes were assessed by spectrophotometric assays. Oxygen consumption and mitochondrial respiration parameters were measured using a Seahorse analyzer. Expression of markers for liver steatosis and dysfunction were also evaluated by reverse transcription­quantitative polymerase chain reaction. The data revealed that fructose and fatty acid combination in vitro had a positive interference on lipogenic pathways, leading to more severe steatosis and liver dysfunction, reduced cell viability, increased apoptosis, oxidative stress and mitochondrial respiration. Hepatic cell abnormalities were almost completely alleviated by silybin treatment. These findings suggest that silybin may serve as a novel and cost­effective dietary supplement for treatment and/or prevention of hepatosteatosis associated with NAFLD progression.


Assuntos
Ácidos Graxos/metabolismo , Frutose/metabolismo , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Substâncias Protetoras/farmacologia , Silibina/farmacologia , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular , Hepatócitos/citologia , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Peroxidação de Lipídeos/efeitos dos fármacos , Hepatopatia Gordurosa não Alcoólica/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Ratos
10.
Mol Med Rep ; 20(2): 1383-1392, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31173243

RESUMO

Hypercholesterolemia is one of the major risk factors for the occurrence and development of atherosclerosis. The most common drugs used to treat hypercholesterolemia are 3­hydroxy­3­methyl­glutaryl­CoA reductase inhibitors, known as statins. Statins induce a beneficial increase in the levels of the low density lipoprotein receptor (LDLR) and additionally upregulate proprotein convertase subtilisin/kexin type 9 (PCSK9), which leads to LDLR degradation. This process causes a negative feedback response that attenuates the lipid lowering effects of statins. Therefore, the development of PCSK9 inhibitors may increase the lipid­lowering functions of statins. In the present study, a drug­screening assay was developed using the human PCSK9 promoter, based on data from a dual­luciferase reporter assay, and the efficacies of various compounds from Traditional Chinese Medicine were examined. Among the compounds examined, SIL was demonstrated to function by targeting PCSK9. It was identified that SIL treatment decreased the expression levels of PCSK9 in HepG2 cells by decreasing the activity of the PCSK9 promoter in a dose­and time­dependent manner. Notably, SIL antagonized the statin­induced phosphorylation of the p38 MAPK signaling pathway. The present study suggested that SIL may be developed as a novel PCSK9 inhibitor that may increase the efficiency of statin treatment.


Assuntos
Hepatoblastoma/metabolismo , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Neoplasias Hepáticas/metabolismo , Pró-Proteína Convertase 9/metabolismo , Silibina/farmacologia , Atorvastatina/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Células Hep G2 , Hepatoblastoma/genética , Hepatoblastoma/patologia , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Fosforilação/efeitos dos fármacos , Regiões Promotoras Genéticas/genética , Pró-Proteína Convertase 9/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Silibina/química , Fatores de Tempo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
11.
Neurochem Res ; 44(8): 1818-1829, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31102026

RESUMO

Excessive physical exercise (overtraining; OT) increases oxidative stress and induces damage in multiple organs including the brain, especially the hippocampus that plays an important role in learning and memory. Silibinin, a natural flavonoid derived from milk thistle of Silybum marianum, has been reported to exert neuroprotective effect. In this study, rats were subjected to overtraining exercise, and the protective effects of silibinin were investigated in these models. Morris water maze and novel object recognition tests showed that silibinin significantly attenuated memory defects in overtrained rats. At the same time, the results of Nissl, TUNEL and SA-ß-gal staining showed that silibinin reversed neuronal loss caused by apoptosis, and delayed cell senescence of the hippocampus in the overtrained rats, respectively. In addition, silibinin decreased malondialdehyde (MDA) levels which is associated with reactive oxygen species (ROS) generation. Silibinin prevented impairment of learning and memory caused by excessive physical exercise in rats, accompanied by reduced apoptosis and senescence in hippocampus cells.


Assuntos
Envelhecimento/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Aprendizagem em Labirinto/efeitos dos fármacos , Transtornos da Memória/tratamento farmacológico , Fármacos Neuroprotetores/uso terapêutico , Silibina/uso terapêutico , Animais , Catalase/metabolismo , Hipocampo/patologia , Masculino , Malondialdeído/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Condicionamento Físico Animal/efeitos adversos , Ratos Sprague-Dawley , Superóxido Dismutase/metabolismo
12.
J Physiol Sci ; 69(4): 643-652, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31087219

RESUMO

Silibinin has been shown to attenuate cognitive dysfunction and inhibit amyloid-beta (Aß) aggregation in Alzheimer's disease (AD) models. However, the underlying mechanism by which silibinin improves cognition remains poorly understood. In this study, we investigated the effect of silibinin on ß-secretase levels, Aß enzymatic degradation, and oxidative stress in the brains of APP/PS1 mice with cognitive impairments. Oral administration of silibinin for 2 months significantly attenuated the cognitive deficits of APP/PS1 mice in the Y-maze test, novel object recognition test, and Morris water maze test. Biochemical analyses revealed that silibinin decreased Aß deposition and the levels of soluble Aß1-40/1-42 in the hippocampus by downregulating APP and BACE1 and upregulating NEP in APP/PS1 mice. In addition, silibinin decreased the MDA content and increased the activities of the antioxidant enzymes CAT, SOD, and NO. Based on our findings, silibinin is a potentially promising agent for preventing AD-associated Aß pathology.


Assuntos
Secretases da Proteína Precursora do Amiloide/metabolismo , Peptídeos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , Silibina/farmacologia , Doença de Alzheimer/metabolismo , Animais , Antioxidantes/metabolismo , Disfunção Cognitiva/tratamento farmacológico , Disfunção Cognitiva/metabolismo , Modelos Animais de Doenças , Regulação para Baixo/efeitos dos fármacos , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Regulação para Cima/efeitos dos fármacos
13.
Int J Mol Sci ; 20(9)2019 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-31058823

RESUMO

Silybin is a flavonolignan extracted from Silybum marianum (milk thistle) with hepatoprotective, antioxidant, and anti-inflammatory activity. Several studies have shown that silybin is highly effective to prevent and treat different types of cancer and that its antitumor mechanisms involve the arrest of the cell cycle and/or apoptosis. An MTT assay was performed to study cell viability, lipid peroxidation, extracellular NO production, and scavenger enzyme activity were studied by Thiobarbituric Acid-Reactive Species (TBARS) assay, NO assay, and MnSOD assay, respectively. Cell cycle and apoptosis analysis were performed by FACS. miRNA profiling were evaluated by real time PCR. In this study, we demonstrated that Silybin induced growth inhibition blocking the Hepg2 cells in G1 phase of cell cycle and activating the process of programmed cell death. Moreover, the antiproliferative effects of silybin were paralleled by a strong increase of the number of ceramides involved in the modulation of miRNA secretion. In particular, after treatment with silybin, miR223-3p and miR16-5p were upregulated, while miR-92-3p was downregulated (p < 0.05). In conclusion, our results suggest that silybin-Induced apoptosis occurs in parallel to the increase of ceramides synthesis and miRNAs secretion in HepG2 cells.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Ceramidas/biossíntese , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , MicroRNAs/genética , Silibina/farmacologia , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Perfilação da Expressão Gênica , Humanos , Metabolismo dos Lipídeos/efeitos dos fármacos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Óxido Nítrico/biossíntese
14.
Respir Res ; 20(1): 79, 2019 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-31023308

RESUMO

BACKGROUND: C-X-C chemokine receptor type 4 (CXCR4) may be involved in the development of pulmonary arterial hypertension (PAH). CXCR4 inhibitor AMD3100 was described to have a positive effect on the prevention of pulmonary arterial muscularization in PAH models. Silibinin is a traditional medicine that has an antagonistic effect on CXCR4. We investigated the effect of silibinin using rat models of PAH. METHODS: PAH was induced by a single subcutaneous injection of monocrotaline. The rats were maintained in a chronic hypoxic condition (10% O2) with or without silibinin. To evaluate the efficacy of silibinin on PAH, right ventricular systolic pressure (RVSP), Fulton index (weight ratio of right ventricle to the left ventricle and septum), percent medial wall thickness (% MT), and vascular occlusion score (VOS) were measured and calculated. Immunohistochemical analysis was performed targeting CXCR4 and c-Kit. Reverse transcription-quantitative polymerase chain reaction was performed for the stem cell markers CXCR4, stromal cell derived factor-1 (SDF-1), c-Kit, and stem cell factor (SCF), and the inflammatory markers monocyte chemoattractant protein 1 (MCP1), interleukin-6 (IL-6), and tumor necrosis factor alpha (TNFα). Statistical analyses were performed using t-test and one-way analysis of variance with Bonferroni's post hoc test. RESULTS: Silibinin treatment for 1 week reduced RVSP and Fulton index. Treatment for 2 weeks reduced RVSP, Fulton index, % MT, and VOS, as well as downregulating the expression of CXCR4, SDF-1, and TNFα in pulmonary arteries. In contrast, treatment for 3 weeks failed to ameliorate PAH. The time-course study demonstrated that RVSP, Fulton index, % MT, and VOS gradually increased over time, with a decrease in the expression of CXCR4 and TNFα occurring after 2 weeks of PAH development. After 3 weeks, SDF-1, c-Kit, and SCF began to decrease and, after 5 weeks, MCP1 and IL-6 gradually accumulated. CONCLUSIONS: The CXCR4 inhibitor silibinin can ameliorate PAH, possibly through the suppression of the CXCR4/SDF-1 axis, until the point where PAH becomes a severe and irreversible condition. Silibinin results in reduced pulmonary arterial pressure and delays pulmonary arteriolar occlusion and pulmonary vascular remodeling.


Assuntos
Modelos Animais de Doenças , Hipertensão Pulmonar/tratamento farmacológico , Hipóxia/tratamento farmacológico , Monocrotalina/toxicidade , Receptores CXCR4/antagonistas & inibidores , Silibina/uso terapêutico , Animais , Hipertensão Pulmonar/induzido quimicamente , Hipertensão Pulmonar/metabolismo , Hipóxia/induzido quimicamente , Hipóxia/metabolismo , Masculino , Substâncias Protetoras/uso terapêutico , Ratos , Ratos Sprague-Dawley , Receptores CXCR4/fisiologia , Resultado do Tratamento
15.
In Vitro Cell Dev Biol Anim ; 55(5): 368-375, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31025252

RESUMO

Ketosis is a condition where ketone bodies are produced as an alternative energy source, due to insufficient glucose for energy production so that the body switches from carbohydrate metabolism to mostly fat metabolism. In this study, we examined the anti-ketosis effects of silibinin, a major active component of silymarin. We induced ketosis in FL83B mouse hepatocytes in vitro by culturing in low glucose media and compared results to hepatocytes maintained in high-glucose conditions. We quantified ß-hydroxybutyrate (BHB) levels with a colorimetric assay. In low-glucose conditions, silibinin reduced the amount of BHB produced, compared to high-glucose conditions; thus, silibinin exhibited an anti-ketotic effect. Ketone body formation during beta oxidation is mediated by 3-hydroxy-3-methylglutaryl-CoA synthase 2 (HMGCS2). The nuclear factor kappa-light-chain-enhancer of activated B cells (NF-kB) regulates the transcription of HMGCS2, and plays a vital role in BHB levels. We showed that silibinin inhibited the expression of HMGCS2 and NF-kB at transcriptional and translational levels. Silibinin also inhibited the nuclear translocation of NF-kB and its DNA binding activity. To elucidate the relationship between HMGCS2 and NF-kB, we tested inhibited and over-expressed NF-kB. We found that NF-kB acted as a positive regulator for HMGCS2 under ketosis treatment conditions.


Assuntos
Hidroximetilglutaril-CoA Sintase/genética , Cetose/tratamento farmacológico , NF-kappa B/genética , Silibina/farmacologia , Ácido 3-Hidroxibutírico/metabolismo , Animais , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Colorimetria , Proteínas de Ligação a DNA/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Glucose/metabolismo , Hepatócitos/efeitos dos fármacos , Humanos , Corpos Cetônicos/biossíntese , Corpos Cetônicos/metabolismo , Cetose/genética , Cetose/metabolismo , Cetose/patologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Camundongos , Transdução de Sinais/efeitos dos fármacos , Silimarina/química , Silimarina/farmacologia
16.
Int J Mol Sci ; 20(7)2019 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-30935093

RESUMO

An ever-growing number of preclinical studies have investigated the tumoricidal activity of the milk thistle flavonolignan silibinin. The clinical value of silibinin as a bona fide anti-cancer therapy, however, remains uncertain with respect to its bioavailability and blood⁻brain barrier (BBB) permeability. To shed some light on the absorption and bioavailability of silibinin, we utilized the Caco-2 cell monolayer model of human intestinal absorption to evaluate the permeation properties of three different formulations of silibinin: silibinin-meglumine, a water-soluble form of silibinin complexed with the amino-sugar meglumine; silibinin-phosphatidylcholine, the phytolipid delivery system Siliphos; and Eurosil85/Euromed, a milk thistle extract that is the active component of the nutraceutical Legasil with enhanced bioavailability. Our approach predicted differential mechanisms of transport and blood⁻brain barrier permeabilities between the silibinin formulations tested. Our assessment might provide valuable information about an idoneous silibinin formulation capable of reaching target cancer tissues and accounting for the observed clinical effects of silibinin, including a recently reported meaningful central nervous system activity against brain metastases.


Assuntos
Silibina/metabolismo , Barreira Hematorretiniana/efeitos dos fármacos , Células CACO-2 , Humanos , Absorção Intestinal/efeitos dos fármacos , Cardo Mariano/química , Extratos Vegetais/farmacologia
17.
Free Radic Res ; 53(7): 714-726, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30947567

RESUMO

The antitumor effects of silibinin are of increasing interest, though its mechanism is not yet clear. The goal of this study was to clarify the mechanism of silibinin-induced cell death in the A431 human epidermoid carcinoma cell line. We used a cell viability assay, flow cytometry, nitric oxide (NO) assay, and western blotting to examine relationships between silibinin, NO generation and apoptosis in A431 cells. Silibinin inhibited A431 cell growth in a dose-dependent manner, inducing mitochondrial damage, and apoptosis at a high dose. At the same time, high dose silibinin increased NO levels in A431 cells and the endothelial nitric oxide synthase (eNOS) inhibitor NG-nitro-L-arginine methylester (L-NAME) attenuated silibinin-induced cell growth inhibition. By western blotting, silibinin caused increased eNOS phosphorylation in the mitochondria. The AMP-activated protein kinase inhibitor compound C significantly decreased p-eNOS expression, while blocking eNOS did not affect p-AMPK levels, suggested that AMPK acted upstream of eNOS. This study showed that silibinin increased NO levels in A431 cells by activating the AMPK-eNOS pathway, leading to mitochondrial dysfunction and apoptosis. In this mechanism of action, mitochondrial eNOS played an important role. The results provided new understanding of the functions of intracellular NO.


Assuntos
Epiderme/metabolismo , Mitocôndrias/metabolismo , Óxido Nítrico Sintase Tipo III/metabolismo , Silibina/uso terapêutico , Apoptose , Humanos , Silibina/farmacologia
18.
Molecules ; 24(7)2019 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-30986937

RESUMO

Silybin has been proposed as a treatment for nonalcoholic steatohepatitis (NASH). In this study, we assessed the effect of Silybin in a well-established in vitro coculture model of early-stage NASH. LX2 and Huh7 cells were exposed to free fatty acid (FFA) and Silybin as mono- or coculture (SCC). Cell viability, LX2 activation, collagen deposition, metalloproteinase 2 and 9 (MMP2-9) activity, and ROS generation were determined at 24, 96, and 144 h. Exposure to FFA induced the activation of LX2 as shown by the increase in cell viability and upregulation of collagen biosynthesis. Interestingly, while cotreatment with Silybin did not affect collagen production in LX2, a significant reduction was observed in SCC. MMP2-9 activity was reduced in FFA-treated Huh7 and SCC and cotreatment with Silybin induced a dose-dependent increase, while no effect was observed in LX2. Silybin also showed antioxidant properties by reducing the FFA-induced production of ROS in all the cell systems. Based on these data, Silybin exerts its beneficial effects by reducing LX2 proliferation and ROS generation. Moreover, MMP2-9 modulation in hepatocytes represents the driving mechanism for the net reduction of collagen in this NASH in vitro model, highlighting the importance of hepatic cells interplay in NASH development and resolution.


Assuntos
Colágeno/metabolismo , Fígado/metabolismo , Silibina/farmacologia , Linhagem Celular , Sobrevivência Celular , Técnicas de Cocultura , Ácidos Graxos não Esterificados , Células Estreladas do Fígado/efeitos dos fármacos , Células Estreladas do Fígado/metabolismo , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Humanos , Fígado/efeitos dos fármacos , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Hepatopatia Gordurosa não Alcoólica/metabolismo , Espécies Reativas de Oxigênio/metabolismo
19.
Oxid Med Cell Longev ; 2019: 6026902, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30891115

RESUMO

Bilirubin is considered to be one of the most potent endogenous antioxidants in humans. Its serum concentrations are predominantly affected by the activity of hepatic bilirubin UDP-glucuronosyl transferase (UGT1A1). Our objective was to analyze the potential bilirubin-modulating effects of natural polyphenols from milk thistle (Silybum marianum), a hepatoprotective herb. Human hepatoblastoma HepG2 cells were exposed to major polyphenolic compounds isolated from milk thistle. Based on in vitro studies, 2,3-dehydrosilybins A and B were selected as the most efficient compounds and applied either intraperitoneally or orally for seven days to C57BL/6 mice. After, UGT1A1 mRNA expression, serum, intrahepatic bilirubin concentrations, and lipoperoxidation in the liver tissue were analyzed. All natural polyphenols used increased intracellular concentration of bilirubin in HepG2 cells to a similar extent as atazanavir, a known bilirubinemia-enhancing agent. Intraperitoneal application of 2,3-dehydrosilybins A and B (the most efficient flavonoids from in vitro studies) to mice (50 mg/kg) led to a significant downregulation of UGT1A1 mRNA expression (46 ± 3% of controls, p < 0.005) in the liver and also to a significant increase of the intracellular bilirubin concentration (0.98 ± 0.03vs.1.21 ± 0.02 nmol/mg, p < 0.05). Simultaneously, a significant decrease of lipoperoxidation (61 ± 2% of controls, p < 0.005) was detected in the liver tissue of treated animals, and similar results were also observed after oral treatment. Importantly, both application routes also led to a significant elevation of serum bilirubin concentrations (125 ± 3% and 160 ± 22% of the controls after intraperitoneal and oral administration, respectively, p < 0.005 in both cases). In conclusion, polyphenolic compounds contained in silymarin, in particular 2,3-dehydrosilybins A and B, affect hepatic and serum bilirubin concentrations, as well as lipoperoxidation in the liver. This phenomenon might contribute to the hepatoprotective effects of silymarin.


Assuntos
Bilirrubina/metabolismo , Flavonoides/isolamento & purificação , Flavonoides/farmacologia , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/metabolismo , Silimarina/isolamento & purificação , Silimarina/farmacologia , Animais , Flavonoides/química , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Glucuronosiltransferase/genética , Glucuronosiltransferase/metabolismo , Heme Oxigenase-1/genética , Heme Oxigenase-1/metabolismo , Células Hep G2 , Humanos , Espaço Intracelular/metabolismo , Fígado/efeitos dos fármacos , Camundongos Endogâmicos C57BL , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Silibina/administração & dosagem , Silibina/farmacologia
20.
Mol Carcinog ; 58(7): 1260-1271, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30912211

RESUMO

Around 80% of nonmelanoma skin cancers (NMSCs) are basal cell carcinoma (BCC), still studies evaluating the efficacy of chemopreventive agents during early stage/s of BCC development are lacking. Accordingly, utilizing the well-established patched (Ptch)+/- mouse model of ultraviolet B (UVB) radiation-induced BCC formation, we excised skin samples from UVB exposed Ptch+/- and Ptch+/+ mice before tumor formation to study the promotion/progression of BCC and to determine the efficacy and target/s of silibinin, a well-known skin cancer chemopreventive agent. UVB exposure for 1 month increased the number of mast cells in Ptch+/- mice by ~48% (P < 0.05), which was completely inhibited by silibinin. Polymerase chain reaction profiler array analysis of skin samples showed strong molecular differences between Ptch+/+ and Ptch+/- mice which were either unexposed or UVB irradiated+/- silibinin treatment. Most notably, silibinin treatment significant decreased the expression of BMP-2, Bbc3, PUMA, and Ccnd1 in Ptch+/- mice irradiated with silibinin + UVB. Additional studies showed that silibinin targets UVB-induced expression of bone morphogenetic protein 2 (BMP-2) in Ptch+/- mouse skin. Last, our studies found that silibinin strongly attenuates UVB-induced BMP-2 expression and DNA damage in Ptch+/- mouse skin ex vivo only after single UVB exposure. Together, our results suggest a possible role of mast cell recruitment and BMP-2 activation in the early stages of BCC development; these are strongly inhibited by silibinin suggesting its possible chemopreventive efficacy against BCC formation in long-term UVB exposure regimen.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Proteína Morfogenética Óssea 2/biossíntese , Carcinoma Basocelular/tratamento farmacológico , Mastócitos/efeitos da radiação , Receptor Patched-1/genética , Silibina/farmacologia , Neoplasias Cutâneas/tratamento farmacológico , Raios Ultravioleta/efeitos adversos , Animais , Proteínas Reguladoras de Apoptose/biossíntese , Carcinoma Basocelular/patologia , Quimioprevenção , Ciclina D1/biossíntese , Dano ao DNA/efeitos dos fármacos , Modelos Animais de Doenças , Mastócitos/patologia , Camundongos , Camundongos Transgênicos , Transdução de Sinais , Pele/patologia , Neoplasias Cutâneas/patologia , Proteínas Supressoras de Tumor/biossíntese
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