Anethole Dithiolethione Research Articles

Synthesis and biological evaluation of lipid-soluble prodrugs of anethole dithiolthione

16 ADT carboxylate esters were prepared by means of esterification and these compounds were expected to increase the bioavailability of 4-hydroxyanehole trithione. In vivo studies showed that ADT concentration of 3a in plasma was much higher than that of ATT during 120 min. Compound 3a could reach blood peak values of ADT at 660.6 ng/mL which was about 14 times of that by ATT. Additionally, the acute toxicity assay indicated high safety of compound 3a that the maximum tolerated dose was no less than 3.25 g/kg.

The antioxidant anethole dithiolethione inhibits monoamine oxidase-B but not monoamine oxidase A activity in extracts of cultured astrocytes

Anethole dithiolethione (ADT) is a clinically available, pluripotent antioxidant proposed as a neuroprotectant for Parkinson's disease (PD). Here, using extracts from cultured astrocytes, containing both monoamine oxidase (MAO) A and B activity, we demonstrate that ADT concentration-dependently inhibits MAO-B activity in a clinically relevant concentration range (0.03-30 microM, IC-50 = 0.5 microM) without affecting MAO A activity. Considering the alleged contribution of MAO activity in general, and MAO-B in particular, to oxidative stress and neurodegeneration in PD, our data further support the neuroprotective potential of ADT.

Nrf2 as a novel molecular target for chemoprevention

One of the rational and effective strategies for chemoprevention is the blockade of DNA damage caused by carcinogenic insult. This can be achieved either by reducing the formation of reactive carcinogenic species or stimulating their detoxification. A wide spectrum of xenobiotic metabolizing enzymes catalyze both phase I (oxidation and reduction) and phase II biotransformation (conjugation) reactions involved in carcinogen activation and/or deactivation. Several antioxidant-response element (ARE)-regulated gene products such as glutathione S-transferase, NAD(P)H:quinone oxidoreductase 1, UDP-glucuronosyltransferase, γ-glutamate cysteine ligase, and hemeoxygenase-1 are known to mediate detoxification and/or to exert antioxidant functions thereby protecting cells from genotoxic damage. The transcription of ARE-driven genes is regulated, at least in part, by nuclear transcription factor erythroid 2p45 (NF-E2)-related factor 2 (Nrf2), which is sequestered in cytoplasm by Kelch-like ECH-associated protein 1 (Keap1). Exposure of cells to ARE inducers results in the dissociation of Nrf2 from Keap1 and facilitates translocation of Nrf2 to the nucleus, where it heterodimerizes with small Maf protein, and binds to ARE, eventually resulting in the transcriptional regulation of target genes. The Nrf2–Keap1–ARE signaling pathway can be modulated by several upstream kinases including phosphatidylinositol 3-kinase, protein kinase C, and mitogen-activated protein kinases. Selected Nrf2–Keap1–ARE activators, such as oltipraz, anethole dithiolethione, sulforaphane, 6-methylsulphinylhexyl isothiocyanate, curcumin, caffeic acid phenethyl ester, 4′-bromoflavone, etc. are potential chemopreventive agents. This mini-review will focus on a chemopreventive strategy directed towards protection of DNA and other important cellular molecules by inducing de novo synthesis of phase II detoxifying or antioxidant genes via the Nrf2–ARE core signaling pathway.

Chemoprevention of lung cancer.

Lung cancer is one of the major causes of cancer-related deaths. Grim mortality figures argue powerfully for new approaches to control this disease. Chemoprevention is the use of specific natural or synthetic chemical agents to reverse, suppress, or prevent carcinogenic progression to invasive cancer. The current article focuses on the field of lung cancer chemoprevention and recent advances. Lung cancer biology and general principles of prevention strategies are also described. Trials in lung cancer chemoprevention have so far produced either neutral or harmful primary end point results whether in the primary, secondary and tertiary settings. The data suggest that lung cancer was not prevented by beta-carotene, alpha-tocopherol, retinal, retinyl palmitate, N-acetylcysteine, or isotretinoin in smokers. The results from the recently completed Canadian study of anethole dithiolethione in smokers with bronchial dysplasia as well secondary analyses of the phase III trials involving selenium and data from the US Intergroup NCI-91-0001 supporting treatment with isotretinoin in never and former smokers are hopeful and may help define new avenues of chemopreventive treatment after scientists and clinicians analyze the information generated. The concept of chemoprevention in lung cancer is still in its infancy but one day may have a significant impact on the incidence and mortality of this leading cancer threat. An improved understanding of carcinogenesis and cancer prevention mechanisms will no doubt aid in the design of future clinical trials and in the validation of candidate agents as well as the development of new targets. Planned or ongoing trials currently are targeting important molecular markers of lung carcinogenesis and progression including cyclooxygenase-2, the ras-signaling pathway through farnesyl transferase inhibitors and the tyrosine kinase/epidermal growth factor receptor pathway. Until such studies are completed however, no drug or drug combination should be used for lung cancer prevention outside of a clinical study.

L’anethole dithiolethione : un agent cytoprotecteur contre la ténotoxicité induite par les fluoroquinolones

Tendinopathy and tendon rupture are the adverse effects observed with fluoroquinolone antibiotics in old patients. The aim of this study was to investigate the effect of anethole dithiolethione (5-[p-methoxyphenyl]3H-1,2-dithiole-3-thione) on the oxidative stress induced by three fluoroquinolones (pefloxacin, ofloxacin, ciprofloxacin) incubated with rabbit tenocyte cell line. Anethole dithiolethione is a well known antioxidant and glutathione inducer. Anethole dithiolethione is widely used in human therapy for its choleretic, sialogogic properties and recently proposed as cytoprotective agent in lung precancerous lesions prevention in smokers. In this purpose, protection against oxidative stress induced by fluoroquinolones has been assessed using cytofluorimetric probes to quantify cytotoxicity and reactive oxygen species production. Fluorescence signal was quantified in 96-well microplates, using cold light cytofluorometer. Significant reactive oxygen species production was detected after 45 minutes for all fluoroquinolones tested. Anethole dithiolethione has been evaluated on this parameter. Anethole dithiolethione significantly (*: P <0.05) reduces and normalizes reactive oxygen species induced by fluoroquinolones. So, anethole dithiolethione (Sulfarlem ®), well known for its antioxidant and glutathione inducing properties, good tissue diffusion and good tolerance in humans, could be beneficially associated to fluoroquinolones, and be proposed as a therapeutic adjuvant to prevent oxidative stress and tendinous adverse effects induced by xenobiotics and more precisely by fluoroquinolones.

432 Anethole dithiolethione (ADT): A new modulator of oxidative stress induced by fluoroquinolone antibiotics in tendon cells

432 Anethole dithiolethione (ADT): A new modulator of oxidative stress induced by fluoroquinolone antibiotics in tendon cells

A phase II clinical trial of anethole dithiolethione (Sialor®, Sulfarlem®) in smokers with bronchial dysplasia

A phase II clinical trial of anethole dithiolethione (Sialor®, Sulfarlem®) in smokers with bronchial dysplasia

The Neuroprotective Antioxidant α-lipoic Acid Induces Detoxication Enzymes in Cultured Astroglial Cells

f -Lipoic acid (LA), an antioxidant with broad neuroprotective capacity, is thought to act by scavenging reactive oxygen species and stimulation of glutathione synthesis. LA shows structural resemblance to dithiolethiones, like anethole dithiolethione (ADT). ADT protects against oxidative damage, primarily by induction of phase II detoxication enzymes, in particular NAD(P)H:quinone oxidoreductase (NQO1) and glutathione- S -transferase (GST). Therefore, we investigated whether LA, like ADT, is capable also of inducing these protective enzymes. Our data show that LA, like ADT, induces a highly significant, time- and concentration dependent, increase in the activity of NQO1 and GST in C6 astroglial cells. The LA or ADT mediated induction of NQO1 was further confirmed by quantitative PCR and western blot analysis. This work for the first time unequivocally demonstrates LA mediated upregulation of phase II detoxication enzymes, which may highly contribute to the compounds' neuroprotective potential. Moreover, the data support the notion of a common mechanism of action of LA and ADT.

Anethole dithiolethione regulates oxidant-induced tyrosine kinase activation in endothelial cells.

Interaction between neutrophils and endothelial cells is one of the first steps in the functional response of polymorphonuclear neutrophils (PMN), and is necessary for their migration toward damaged tissues. PMN activation, leading to their adhesion to and migration between endothelial cells, is part of a complex phenomenon that can be altered in pathological situations such as the ischemia-reperfusion syndrome, in which large numbers of PMN are recruited to the tissue and release reactive oxygen species (ROS) near the vessel wall. ROS have been implicated in the pathogenesis of various inflammatory diseases. The increased adhesion of PMN to ROS-stimulated endothelial cells involves an increase in tyrosine phosphorylation of a tyrosine kinase focal adhesion kinase (p125FAK) and several cytoskeleton proteins, including paxillin and p130 cas. We examined the role of glutathione (GSH) in the regulation of this adhesion phenomenon and in the increased tyrosine phosphorylation induced by ROS. For this purpose we used anethole dithiolthione (ADT), which increases the glutathione synthesis by activating gamma-glutamyl-cysteine synthetase. We found that ADT reduced both PMN adhesion to ROS-stimulated human umbilical vein endothelial cells (HUVEC) and tyrosine phosphorylation of p125FAK and paxillin. ADT increased redox status by increasing intracellular GSH content in oxidized cells. These results show that GSH can reverse the effect of oxidation on tyrosine kinase activation and phosphorylation, and thus plays an important role in cell signaling. They also confirm the antioxidant activity of ADT.

Tacrine-induced Reactive Oxygen Species in a Human Liver Cell Line: The Role of Anethole Dithiolethione as a Scavenger

The mechanisms leading to tacrine (THA) hepatotoxic effects are not yet fully understood. Reactive oxygen species (ROS) overproduction and intracellular reduced glutathione (GSH) depletion are common mechanisms involved in drug toxicity. The aim of this study was to investigate, on the human liver cell line HepG2, whether THA at human blood concentrations induces ROS production stimulation and/or GSH depletion. A possible effect of a free radical scavenger, anethole dithiolethione (ADT), was also assessed. ROS production was measured with a fluorogen probe 2′,7′-dichlorofluorescin diacetate (DCFH-DA). Reduced GSH and cell viability were measured with, respectively, monochlorobimane (mBCl) and neutral red probes. Assays were performed directly on living adherent cells in 96-well microplates, and sensitive fluorescent detection used microplate cytofluorimetry with cold light fluorimetry technology. The results showed that THA induced a concentration-dependent increase in ROS production and a decrease in GSH. Furthermore, for THA concentrations between 10 and 100 μ m, ADT protected cells from ROS production stimulation and GSH depletion induced by THA. In conclusion, our in vitro study demonstrates that oxidative stress, evidenced by enhanced ROS production and GSH depletion, is a mechanism involved in THA cytotoxicity. Moreover, ADT is effective in preventing THA-induced injury.

27] Quantitation of anethole dithiolthione using high performance liquid chromatography with electrochemical detection

Publisher Summary This chapter describes the quantitation of anethole dithiolethione using high performance liquid chromatography (HPLC) with electrochemical detection. The chapter discusses a highly reproducible and effective method to measure anethole dithiolethione (ADT) in cells as well as in aqueous solutions. The present method is 50-fold more sensitive than previously reported for fluorescence detection of ADT following HPLC separation. In addition, the extraction method described in the chapter removes nearly 100% of the ADT from cellular or aqueous samples. In addition to the increased sensitivity of the EC method, this new method also allows measurement of any redox products of ADT. Because ADT has a similar structure to lipoic acid, ADT may interact with other cellular thiols in a manner similar to lipoic acid. When lipoic acid enters the cell, the disulfide bond is reduced to form dihydrolipoic acid. It is not yet known whether ADT is metabolized in a similar manner when it is incubated with Wurzburg cells.

Anethole dithiolethione, a putative neuroprotectant, increases intracellular and extracellular glutathione levels during starvation of cultured astroglial cells.

Astroglial cells protect neurons against oxidative damage. The antioxidant glutathione plays a pivotal role in the neuroprotective action of astroglial cells which is impaired following loss of glutathione. Anethole dithiolethione (ADT), a sulfur-containing compound which is used in humans as a secretagogue, increases glutathione levels in cultured astroglial cells under "physiological" conditions and is thought thereby to protect against oxidative damage. Presently, we report the effect of ADT (3-100 microM) on glutathione content of and efflux from rat primary astroglia-rich cultures under "pathological" conditions, i.e., extended deprivation of glucose and amino acids. Although cellular viability was not affected significantly, starvation of these cultures for 24 h in a bicarbonate buffer lacking glucose and amino acids led to a decrease in glutathione and protein content of approximately 43% and 40%, respectively. Although no effect on the protein loss occurred, the presence of ADT during starvation counteracted the starvation-induced loss of intracellular glutathione in a concentration-dependent way. At a concentration of 100 microM ADT even a significant increase in astroglial glutathione content was noted after 24 h of starvation. Alike intracellular glutathione levels, the amount of glutathione found in the buffer was elevated substantially if ADT was present during starvation. This ADT-mediated, apparent increase in glutathione efflux was additive to the stimulatory effect on extracellular glutathione levels of acivicin (100 microM), an inhibitor of extracellular enzymatic glutathione breakdown. However, the ADT-induced elevation of both intra- and extracellular glutathione content during starvation was prevented completely by coincubation with buthionine sulfoximine (10 microM), an inhibitor of glutathione synthesis. These results demonstrate that, most likely through stimulation of glutathione synthesis, ADT enables astroglial cells to maintain higher intra- and extracellular levels of glutathione under adverse conditions. Considering the lowered glutathione levels in neurodegenerative syndromes, we conclude that further evaluation of the therapeutic potential of the compound is warranted.

Protective Effects of Anethole Dithiolethione against Oxidative Stress-induced Cytotoxicity in Human Jurkat T Cells

The protective effects of anethole dithiolethione (ADT) against H 2O 2- or 4-hydroxynonenal (HNE)-induced cytotoxicity in human Jurkat T cells were investigated. Jurkat T cells were pretreated with ADT (10–50 μM) for 18 hr and then challenged with H 2O 2 or HNE for up to 4 hr. Cytotoxicity was assessed by measuring: 1) leakage of lactate dehydrogenase from cells to medium; and 2) exclusion of the DNA intercalating fluorescent probe propidium iodide by viable cells. Pretreatment of cells with ADT (10 or 25 μM) for 18 hr significantly protected cells against H 2O 2- or HNE-induced cytotoxicity. Treatment of cells with ADT (10–50 μM) for 72 hr significantly increased the activities of catalase and glutathione reductase. The maximum effect of ADT treatment on the activity of these enzymes was observed when cells were treated with 25 μM of ADT for 72 hr. A significant increase in cellular GSH was observed in cells that were treated with ADT for 72 hr. Using monobromobimane as a thiol probe, we consistently observed that cells pretreated for 18 hr with ADT (25 or 50 μM) had also increased total thiol content. Exposure of Jurkat T cells to H 2O 2 or HNE resulted in a time-dependent decrease in cellular GSH. ADT (10–50 μM, 18 hr) pretreatment circumvented H 2O 2-dependent lowering of cellular GSH. In conclusion, ADT proved to be a potent cytoprotective thiol antioxidant with multifaceted mechanisms of action, suggesting that the drug has a remarkable therapeutic potential.

P1C56 - Cytoprotective effect of anethole dithiole thione (sulfarlem®) as a free radical scavenger-evaluation by microplate cytofluorimetry

A GABAA receptor δ subunit-deficient mouse line was created by homologous recombination in embryonic stem cells to investigate the role of the subunit in the brain GABAA receptors. High-affinity [3H]muscimol binding to GABA sites as studied by ligand autoradiography was reduced in various brain regions of δ−/− animals. [3H]Ro 15-4513 binding to benzodiazepine sites was increased in δ−/− animals, partly due to an increment of diazepam-insensitive receptors, indicating an augmented forebrain assembly of γ2 subunits with α4 subunits. In the western blots of forebrain membranes of δ−/− animals, the level of γ2 subunit was increased and that of α4 decreased, while the level of α1 subunits remained unchanged. In the δ−/− forebrains, the remaining α4 subunits were associated more often with γ2 subunits, since there was an increase in the α4 subunit level immunoprecipitated by the γ2 subunit antibody. The pharmacological properties of t-butylbicyclophosphoro[35S]thionate binding to the integral ion-channel sites were slightly altered in the forebrain and cerebellum, consistent with elevated levels of α4γ2 and α6γ2 subunit-containing receptors, respectively.The altered pharmacology of forebrain GABAA receptors and the decrease of the α4 subunit level in δ subunit-deficient mice suggest that the δ subunit preferentially assembles with the α4 subunit. The δ subunit seems to interfere with the co-assembly of α4 and γ2 subunits and, therefore, in its absence, the γ2 subunit is recruited into a larger population of α4 subunit-containing functional receptors. These results support the idea of subunit competition during the assembly of native GABAA receptors.

Anethole dithiolethione prevents oxidative damage in glutathione-depleted astrocytes

Astrocytes protect neurons against reactive oxygen species such as hydrogen peroxide, a capacity which reportedly is abolished following loss of the antioxidant glutathione. Anethole dithiolethione, a sulfur-containing compound which is used in humans, is known to increase cellular glutathione levels and thought thereby to protect against oxidative damage. In the present study we found that anethole dithiolethione increased the glutathione content of cultured rat striatal astrocytes. This effect was abolished by coincubation with the glutathione synthesis inhibitor buthionine sulfoximine. Nevertheless, in the presence of buthionine sulfoximine, despite the lack of an increase in the lowered glutathione level, anethole dithiolethione fully protected the astrocytes against the enhanced toxicity of hydrogen peroxide. Thus, apparently other mechanisms than stimulation of glutathione synthesis are involved in the compound's protective action in astrocytes. Considering the occurrence of lowered glutathione levels in neurodegenerative syndromes, we conclude that further evaluation of the therapeutic potential of anethole dithiolethione is warranted.

Anethole dithiolethione prevents oxidative damage in glutathione-depleted astrocytes

Astrocytes protect neurons against reactive oxygen species such as hydrogen peroxide, a capacity which reportedly is abolished following loss of the antioxidant glutathione. Anethole dithiolethione, a sulfur-containing compound which is used in humans, is known to increase cellular glutathione levels and thought thereby to protect against oxidative damage. In the present study we found that anethole dithiolethione increased the glutathione content of cultured rat striatal astrocytes. This effect was abolished by coincubation with the glutathione synthesis inhibitor buthionine sulfoximine. Nevertheless, in the presence of buthionine sulfoximine, despite the lack of an increase in the lowered glutathione level, anethole dithiolethione fully protected the astrocytes against the enhanced toxicity of hydrogen peroxide. Thus, apparently other mechanisms than stimulation of glutathione synthesis are involved in the compound's protective action in astrocytes. Considering the occurrence of lowered glutathione levels in neurodegenerative syndromes, we conclude that further evaluation of the therapeutic potential of anethole dithiolethione is warranted.

Comparative effects of three chromium compounds on mouse neuroblastoma cells cultured in vitro

The mechanisms leading to tacrine (THA) hepatotoxic effects are not yet fully understood. Reactive oxygen species (ROS) overproduction and intracellular reduced glutathione (GSH) depletion are common mechanisms involved in drug toxicity. The aim of this study was to investigate, on the human liver cell line HepG2, whether THA at human blood concentrations induces ROS production stimulation and/or GSH depletion. A possible effect of a free radical scavenger, anethole dithiolethione (ADT), was also assessed. ROS production was measured with a fluorogen probe 2′,7′-dichlorofluorescin diacetate (DCFH-DA). Reduced GSH and cell viability were measured with, respectively, monochlorobimane (mBCl) and neutral red probes. Assays were performed directly on living adherent cells in 96-well microplates, and sensitive fluorescent detection used microplate cytofluorimetry with cold light fluorimetry technology. The results showed that THA induced a concentration-dependent increase in ROS production and a decrease in GSH. Furthermore, for THA concentrations between 10 and 100 μm, ADT protected cells from ROS production stimulation and GSH depletion induced by THA. In conclusion, our in vitro study demonstrates that oxidative stress, evidenced by enhanced ROS production and GSH depletion, is a mechanism involved in THA cytotoxicity. Moreover, ADT is effective in preventing THA-induced injury.

32] Anethole dithiolethione: Biochemical considerations

This chapter focuses on the biochemical considerations of Anethole Dithiolethione (ADT). Certain sulfur-containing compounds likely play vital roles in the physiology of the organism, and others are among the effective drugs currently employed in human therapy. The cyclic sulfur-containing compounds, termed 1,2-dithiol-3-thiones, are representatives of a specific class of sulfur-containing compounds, primarily of synthetic origin but also found in trace amounts in certain cruciferous vegetables. These agents possess antioxidant, chemoprotective, and chemotherapeutic activities. One substituted member of this class is prescribed as choleretic and sialagogue, another was used as antischistosomal agent. One molecule of special interest is 5-(p-methoxyphenyl)-3H-1,2-dithiol-3-thione, also termed anethole dithiolethione. Early experiments with dogs bearing fixed biliary fistulae revealed that ADT induces an intense, enduring choleresis after ingestion, which can be demonstrated by monitoring the secretion of biliary cholesterol. Among the cyclic sulfur-containing compounds, termed 1,2-dithiol-3-thiones, a molecule of particular interest is ADT, which is marketed as a choleretic and sialagogue, and which also exerts chemoprotective effects. The chemoprotective effects of this 1,2-dithiol-3-thione may be related mainly to the increase in the activity of detoxification enzymes such as glutathione S-transferases and NAD(P)H:quinone reductase, which promote the elimination of xenobiotics and their activated metabolites via conjugation reactions, particularly with glutathione.

33] Use of linoleic acid radiolysis for assay of antioxidant action of anethole dithiolethione

This chapter focuses on the use of linoleic acid radiolysis for assay of antioxidant action of anethole dithiolethione. Sulfarlem (p-anisyldithiolthione) is a sulfur-containing heterocyclic compound that exhibits free radical scavenging (antioxidant) properties. Radiolysis may be used in the characterization of the radical mechanisms involved in free radical scavenging. The study described in this chapter shows how radiolysis experiments performed in oxygen-saturated micellar media can afford quantitative results concerning the prevention of linoleic acid peroxidation by ADT. γ-Radiolysis can, therefore, be an efficient method of testing the capability of a supposed antioxidant compound to play such a role toward peroxidation chains. The chapter also discusses radiolysis of aqueous linoleic acid micelles. The fact that the degradation of Linoleic acid (LH) and the formation of dienes decrease in the presence of Sulfarlem (ADT) indicates that ADT is capable of preventing peroxidation of LH. The use of γ-radiolysis of oxygen-saturated linoleic acid-aqueous micelle systems affords an efficient method for evaluating the ability of antioxidant molecules such as ADT to prevent peroxidation chain phenomena.

Study of glutathione and glutathione related enzymes in acetaminophen-poisoned mice. Prevention by anethole trithione pretreatment.

For the general purpose of re-examining the pharmacological properties of the choleretic drug anethole trithione (Anethole dithiolthione = ADT), it was previously demonstrated that low dosage of ADT, administered p.o. 1 h prior to hepatotoxins, exhibited a marked hepatoprotective effect against carbon tetrachloride in rats and acetaminophen (AAP) in mice (Warnet et al 1987). Then, a preliminary kinetic study of the hepatoprotective effect of ADT was performed in mice.KeywordsAminotransferase ActivityHepatoprotective EffectMercapturic AcidGamma GlutamylcysteineChemoprotective EffectThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.