Antibacterial activity of disulfiram and its metabolites

Disulfiram Reduces Atherosclerosis and Enhances Efferocytosis, Autophagy, and Atheroprotective Gut Microbiota in Hyperlipidemic Mice

BACKGROUND

Pyroptosis executor GsdmD (gasdermin D) promotes atherosclerosis in mice and humans. Disulfiram was recently shown to potently inhibit GsdmD, but the in vivo efficacy and mechanism of disulfiram's antiatherosclerotic activity is yet to be explored.

METHODS AND RESULTS

We used human/mouse macrophages, endothelial cells, and smooth muscle cells and a hyperlipidemic mouse model of atherosclerosis to determine disulfiram antiatherosclerotic efficacy and mechanism. The effects of disulfiram on several atheroprotective pathways such as autophagy, efferocytosis, phagocytosis, and gut microbiota were determined. Atomic force microscopy was used to determine the effects of disulfiram on the biophysical properties of the plasma membrane of macrophages. Disulfiram-fed hyperlipidemic apolipoprotein E-/- mice showed significantly reduced interleukin-1β release upon in vivo Nlrp3 (NLR family pyrin domain containing 3) inflammasome activation. Disulfiram-fed mice showed smaller atherosclerotic lesions (~27% and 29% reduction in males and females, respectively) and necrotic core areas (~50% and 46% reduction in males and females, respectively). Disulfiram induced autophagy in macrophages, smooth muscle cells, endothelial cells, hepatocytes/liver, and atherosclerotic plaques. Disulfiram modulated other atheroprotective pathways (eg, efferocytosis, phagocytosis) and gut microbiota. Disulfiram-treated macrophages showed enhanced phagocytosis/efferocytosis, with the mechanism being a marked increase in cell-surface expression of efferocytic receptor MerTK. Atomic force microscopy analysis revealed altered biophysical properties of disulfiram-treated macrophages, showing increased order-state of plasma membrane and increased adhesion strength. Furthermore, 16sRNA sequencing of disulfiram-fed hyperlipidemic mice showed highly significant enrichment in atheroprotective gut microbiota Akkermansia and a reduction in atherogenic Romboutsia species.

CONCLUSIONS

Taken together, our data show that disulfiram can simultaneously modulate several atheroprotective pathways in a GsdmD-dependent as well as GsdmD-independent manner.

Disulfiram reduces atherosclerosis and enhances efferocytosis, autophagy, and atheroprotective gut microbiota in hyperlipidemic mice

Pyroptosis executor Gasdermin (GsdmD) promotes atherosclerosis in mice and humans. Disulfiram (DSF) was recently shown to potently inhibit GsdmD, but the in-vivo efficacy and mechanism of DSF's anti-atherosclerotic activity is yet to be explored. We used human/mouse macrophages and a hyperlipidemic mouse model of atherosclerosis to determine DSF anti-atherosclerotic efficacy and mechanism. DSF-fed hyperlipidemic apoE -/- mice showed significantly reduced IL-1β release upon in-vivo Nlrp3 inflammasome assembly and showed smaller atherosclerotic lesions (∼27% and 29% reduction in males and females, respectively). The necrotic core area was also smaller (∼50% and 46% reduction in DSF-fed males and females, respectively). DSF induced autophagy in macrophages, hepatocytes/liver, and in atherosclerotic plaques. DSF modulated other atheroprotective pathways such as efferocytosis, phagocytosis, and gut microbiota. DSF-treated macrophages showed enhanced phagocytosis/efferocytosis, with a mechanism being a marked increase in cell-surface expression of efferocytic receptor MerTK. Atomic-force microscopy analysis revealed altered biophysical membrane properties of DSF treated macrophages, showing increased ordered-state of the plasma membrane and increased adhesion strength. Furthermore, the 16sRNA sequencing of DSF-fed hyperlipidemic mice showed highly significant enrichment in atheroprotective gut microbiota Akkermansia and a reduction in atherogenic Romboutsia species. Taken together, our data shows that DSF can simultaneously modulate multiple atheroprotective pathways, and thus may serve as novel adjuvant therapeutic to treat atherosclerosis.

AADB: A Manually Collected Database for Combinations of Antibiotics With Adjuvants

Antimicrobial resistance is a global public health concern. The lack of innovations in antibiotic development has led to renewed interest in antibiotic adjuvants. However, there is no database to collect antibiotic adjuvants. Herein, we build a comprehensive database named Antibiotic Adjuvant DataBase (AADB) by manually collecting relevant literature. Specifically, AADB includes 3,035 combinations of antibiotics with adjuvants, covering 83 antibiotics, 226 adjuvants, and 325 bacterial strains. AADB provides user-friendly interfaces for searching and downloading. Users can easily obtain these datasets for further analysis. In addition, we also collected related datasets (e.g., chemogenomic and metabolomic data) and proposed a computational strategy to dissect these datasets. As a test case, we identified 10 candidates for minocycline, and 6 of 10 candidates are the known adjuvants that synergize with minocycline to inhibit the growth of E. coli BW25113. We hope that AADB can help users to identify effective antibiotic adjuvants. AADB is freely available at http://www.acdb.plus/AADB.

Resensitizing multidrug-resistant Gram-negative bacteria to carbapenems and colistin using disulfiram

The increasing incidence of bacterial infections caused by multidrug-resistant (MDR) Gram-negative bacteria has deepened the need for new effective treatments. Antibiotic adjuvant strategy is a more effective and economical approach to expand the lifespan of currently used antibiotics. Herein, we uncover that alcohol-abuse drug disulfiram (DSF) and derivatives thereof are potent antibiotic adjuvants, which dramatically potentiate the antibacterial activity of carbapenems and colistin against New Delhi metallo-β-lactamase (NDM)- and mobilized colistin resistance (MCR)-expressing Gram-negative pathogens, respectively. Mechanistic studies indicate that DSF improves meropenem efficacy by specifically inhibiting NDM activity. Moreover, the robust potentiation of DSF to colistin is due to its ability to exacerbate the membrane-damaging effects of colistin and disrupt bacterial metabolism. Notably, the passage and conjugation assays reveal that DSF minimizes the evolution and spread of meropenem and colistin resistance in clinical pathogens. Finally, their synergistic efficacy in animal models was evaluated and DSF-colistin/meropenem combination could effectively treat MDR bacterial infections in vivo. Taken together, our works demonstrate that DSF and its derivatives are versatile and potent colistin and carbapenems adjuvants, opening a new horizon for the treatment of difficult-to-treat infections.

Applications and Opportunities in Using Disulfides, Thiosulfinates, and Thiosulfonates as Antibacterials

Sulfur-containing molecules have a long history of bioactivity, especially as antibacterial agents in the fight against infectious pathogens. Organosulfur compounds from natural products have been used to treat infections throughout history. Many commercially available antibiotics also have sulfur-based moieties in their structural backbones. In the following review, we summarize sulfur-containing antibacterial compounds, focusing on disulfides, thiosulfinates, and thiosulfonates, and opportunities for future developments in the field.

Clinical, pharmacological, and formulation evaluation of disulfiram in the treatment of glioblastoma - a systematic literature review

INTRODUCTION

Glioblastoma (GB) is one of the most challenging central nervous system (CNS) tumors in treatment options and response, urging the development of novel management strategies. The anti-alcoholism drug, disulfiram (DS), has a potential anticancer activity, and its complex mechanism of action is assumed to be well exploited against the heterogeneous GB.

AREA COVERED

Through a systematic literature review about repositioning DS to GB treatment, an evaluation of the clinical, pharmacological, and formulation strategies is provided to specify the challenges of drug delivery and thus to advance its clinical translation. From six databases, 35 articles were selected, including case report (1); clinical trials (3); original articles mainly representing in vitro and preclinical pharmacological data, and 10 dealing with technological approaches.

EXPERT OPINION

The repositioning of DS in GB treatment is facing drug and tumor-associated limitations due to the oral drug's low bioavailability, unwanted metabolism, and inefficient delivery to brain-tumor tissue. Development strategies using molecular encapsulation of DS and the parenteral dosage forms improve the anticancer pharmacology of the drug. The development of optimized drug delivery systems (DDS) shows promise for the clinical translation of DS into GB adjuvant therapy.

Disulfiram: Mechanisms, Applications, and Challenges

Background: Since disulfiram’s discovery in the 1940s and its FDA approval for alcohol use disorder, other indications have been investigated. This review describes potential clinical applications, associated risks, and challenges. Methods: For this narrative review, a PubMed search was conducted for articles addressing in vivo studies of disulfiram with an emphasis on drug repurposing for the treatment of human diseases. The key search terms were “disulfiram” and “Antabuse”. Animal studies and in vitro studies highlighting important mechanisms and safety issues were also included. Results: In total, 196 sources addressing our research focus spanning 1948–2022 were selected for inclusion. In addition to alcohol use disorder, emerging data support a potential role for disulfiram in the treatment of other addictions (e.g., cocaine), infections (e.g., bacteria such as Staphylococcus aureus and Borrelia burgdorferi, viruses, parasites), inflammatory conditions, neurological diseases, and cancers. The side effects range from minor to life-threatening, with lower doses conveying less risk. Caution in human use is needed due to the considerable inter-subject variability in disulfiram pharmacokinetics. Conclusions: While disulfiram has promise as a “repurposed” agent in human disease, its risk profile is of concern. Animal studies and well-controlled clinical trials are needed to assess its safety and efficacy for non-alcohol-related indications.

Effect of Disulfiram on the Reproductive Capacity of Female Mice

In the process of assisted reproduction, the high-oxygen in vitro environment can easily cause oxidative damage to oocytes. Disulfiram (DSF) can play an anti-oxidant or pro-oxidant role in different cells, and the effect of DSF on oocytes remains unclear. Moreover, it remains unclear whether the use of DSF in the early stages of pregnancy has a negative impact on the fetus. In this study, we found that DSF increased serum FSH levels and increased the ovulation rate in mice. Moreover, DSF enhanced the antioxidant capacity of oocytes and contributed to the success rate of in vitro fertilization. Moreover, the use of DSF in early pregnancy in mice increased the uterine horn volume and the degree of vascularization, which contributed to a successful pregnancy. In addition, it was found that DSF regulated the mRNA expression of angiogenesis-related genes (VEGF), follicular development-related genes (C1QTNF3, mTOR and PI3K), ovulation-related genes (MAPK1, MAPK3 and p38 MAPK) and antioxidant-related genes (GPX4 and CAT). These results indicate that DSF is helpful for increasing the antioxidant capacity of oocytes and the ovulation rate. In early pregnancy in mice, DSF promotes pregnancy by increasing the degree and volume of uterine vascularization.

Antimicrobial pharmacodynamics of vancomycin and disulfiram (Antabuse®) in Staphylococcus aureus

Introduction

Intravenous vancomycin (VAN) is the primary treatment for systemic infections due to methicillin-resistant Staphylococcus aureus (MRSA). Pharmacokinetic/pharmacodynamic target (PK/PD) indices for VAN therapies are more difficult to achieve for MRSA isolates with a minimum inhibitory concentration (MIC) greater than 1 µg mL^-1. This research investigated the in vitro antimicrobial PD interaction of disulfiram (DSF) with VAN as a potential adjuvant therapy for infections due to these bacteria.

Methods

The antimicrobial interaction was assessed by differential analysis using checkerboard titration testing, time-kill studies, flow cytometry, and the post-antibiotic effect (PAE) experiment. Ten MRSA strains with MICs ranging from 1 to >256 µg mL^-1 for VAN were evaluated. A comprehensive PD assessment of the VAN/DSF interaction was performed using the VAN-intermediate (VISA) strain Mu50 (MIC 8 µg mL^-1).

Results

The addition of DSF lowered the MIC and minimum bactericidal concentration (MBC) of VAN in either a synergistic or additive manner for the MRSA panel. Optimal bactericidal effects and suppression of VISA Mu50 growth were observed with a 4/8 µg mL^-1 combination of VAN/DSF, but not the individual drugs. Flow cytometry further confirmed the enhanced killing action on a cellular level; however, the addition of DSF had an overall antagonistic effect on the PAEs for VAN.

Discussion

This research established that DSF exhibits additive to synergistic killing action with VAN for MRSA. Conversely, antagonism was observed on the PAE of VAN with DSF addition for the Mu50 strain. Flow cytometry further confirmed the enhanced bactericidal effect on a cellular level while revealing that DSF may counteract the muropeptide fortification mechanism against VAN in VISA.

Repurposing Disulfiram as an Antimicrobial Agent in Topical Infections

Antimicrobial drugs applied topically offer several advantages. However, the widespread use of antibiotics has led to increasing antimicrobial resistance. One interesting approach in the drug discovery process is drug repurposing. Disulfiram, which was originally approved as an anti-alcoholism drug, offers an attractive alternative to treat topical multidrug resistance bacteria in skin human infections. This study aimed to evaluate the biopharmaceutical characteristics of the drug and the effects arising from its topical application in detail. Microdilution susceptibility testing showed antibacterial activity against Gram-positive bacteria Staphylococcus aureus and Streptococcus pyogenes. Dermal absorption revealed no permeation in pig skin. The quantification of the drug retained in pig skin demonstrated concentrations in the stratum corneum and epidermis, enough to treat skin infections. Moreover, in vitro cytotoxicity and micro-array analyses were performed to better understand the mechanism of action and revealed the importance of the drug as a metal ion chelator. Together, our findings suggest that disulfiram has the potential to be repurposed as an effective antibiotic to treat superficial human skin infections.

Disulfiram Is Effective against Drug-Resistant Mycobacterium abscessus in a Zebrafish Embryo Infection Model

Mycobacterium abscessus is an emerging nontuberculous mycobacterium (NTM) pathogen infecting susceptible people with cystic fibrosis (CF) and non-CF bronchiectasis. Here, we demonstrated the activity of an FDA-approved drug, disulfiram, against drug-susceptible and drug-resistant M. abscessus strains utilizing in vitro and intracellular macrophage assays and a zebrafish embryo infection model. These data demonstrate effective antimicrobial activity of disulfiram against M. abscessus infection in vivo and strongly support further study of disulfiram in human NTM infections.

The Efficacy and Biopharmaceutical Properties of a Fixed-Dose Combination of Disulfiram and Benzyl Benzoate

Scabies and hair lice are parasitic diseases that affect human skin and hair, respectively. The incidence and resistances of these infections are increasing. Tenutex^® (disulfiram and benzyl benzoate emulsion) is an alternative to standard insecticides to avoid resistances. The aim of the work is to evaluate the transdermal absorption and the in vitro efficacy against scabies and hair lice after different exposition times. Dermatomed human skin was used to assess the dermal absorption using a validated High Performance Liquid Chromatography (HPLC) method. HEK001 keratinocytes were used to evaluate the cytotoxicity of benzyl benzoate. Only benzyl benzoate was able to cross the skin, but it did not show cytotoxicity at any of the tested concentrations. The product efficacy was tested on Psoroptes ovis after direct contact and after administration on sheep skin explants at different contact times. Permethrin/malathion-resistant strains of Pediculus humanis capitis adults and eggs were directly exposed to Tenutex, and the vitality and hatchability, respectively, were evaluated. The anti-scabies study demonstrated that exposure for 6 or 24 h completely eradicated the parasite. The pediculicidal activity of Tenutex exhibited superior efficacy than standard treatment on resistant lice. The positive results obtained suggest that Tenutex^® is a good treatment option, especially in drug resistance situations.

The combination of diethyldithiocarbamate and copper ions is active against Staphylococcus aureus and Staphylococcus epidermidis biofilms in vitro and in vivo

Staphylococcus aureus and Staphylococcus epidermidis are associated with life-threatening infections. Despite the best medical care, these infections frequently occur due to antibiotic resistance and the formation of biofilms of these two bacteria (i.e., clusters of bacteria embedded in a matrix). As a consequence, there is an urgent need for effective anti-biofilm treatments. Here, we describe the antibacterial properties of a combination treatment of diethyldithiocarbamate (DDC) and copper ions (Cu²⁺) and their low toxicity in vitro and in vivo. The antibacterial activity of DDC and Cu²⁺ was assessed in vitro against both planktonic and biofilm cultures of S. aureus and S. epidermidis using viability assays, microscopy, and attachment assays. Cytotoxicity of DDC and Cu²⁺ (DDC-Cu²⁺) was determined using a human fibroblast cell line. In vivo antimicrobial activity and toxicity were monitored in Galleria mellonella larvae. DDC-Cu²⁺ concentrations of 8 μg/ml DDC and 32 μg/ml Cu²⁺ resulted in over 80% MRSA and S. epidermidis biofilm killing, showed synergistic and additive effects in both planktonic and biofilm cultures of S. aureus and S. epidermidis, and synergized multiple antibiotics. DDC-Cu²⁺ inhibited MRSA and S. epidermidis attachment and biofilm formation in the xCELLigence and Bioflux systems. In vitro and in vivo toxicity of DDC, Cu²⁺ and DDC-Cu²⁺ resulted in > 70% fibroblast viability and > 90% G. mellonella survival. Treatment with DDC-Cu²⁺ significantly increased the survival of infected larvae (87% survival of infected, treated larvae vs. 47% survival of infected, untreated larvae, p < 0.001). Therefore, DDC-Cu²⁺ is a promising new antimicrobial with activity against planktonic and biofilm cultures of S. epidermidis and S. aureus and low cytotoxicity in vitro. This gives us high confidence to progress to mammalian animal studies, testing the antimicrobial efficacy and safety of DDC-Cu²⁺.

The NLRP3 Inflammasome Pathway: A Review of Mechanisms and Inhibitors for the Treatment of Inflammatory Diseases

The NLRP3 inflammasome is a multiprotein complex that plays a pivotal role in regulating the innate immune system and inflammatory signaling. Upon activation by PAMPs and DAMPs, NLRP3 oligomerizes and activates caspase-1 which initiates the processing and release of pro-inflammatory cytokines IL-1β and IL-18. NLRP3 is the most extensively studied inflammasome to date due to its array of activators and aberrant activation in several inflammatory diseases. Studies using small molecules and biologics targeting the NLRP3 inflammasome pathway have shown positive outcomes in treating various disease pathologies by blocking chronic inflammation. In this review, we discuss the recent advances in understanding the NLRP3 mechanism, its role in disease pathology, and provide a broad review of therapeutics discovered to target the NLRP3 pathway and their challenges.

Disulfiram: A Repurposed Drug in Preclinical and Clinical Development for the Treatment of Infectious Diseases

This article reviews preclinical and clinical studies on the repurposed use of disulfiram (Antabuse) as an antimicrobial agent. Preclinical research covered on the alcohol sobriety aid includes uses as an anti-MRSA agent, a carbapenamase inhibitor, antifungal drug for candidiasis, and treatment for parasitic diseases due to protozoa (e.g., giardiasis, leishmaniasis, malaria) and helminthes (e.g., schistosomiasis, trichuriasis). Past, current, and pending clinical studies on disulfiram as a post-Lyme disease syndrome (PTLDS) therapy, an HIV latency reversal agent, and intervention for COVID-19 infections are also reviewed..

Disulfiram enhances meropenem activity against NDM- and IMP-producing carbapenem-resistant Acinetobacter baumannii infections

OBJECTIVES

To evaluate the in vitro and in vivo efficacy of the FDA-approved drug disulfiram in combination with meropenem against MBL-expressing carbapenem-resistant Acinetobacter baumannii.

METHODS

Chequerboard and antibiotic resistance reversal analysis were performed using 25 clinical isolates producing different MBLs. Three representative strains harbouring NDM, IMP or non-MBL genes were subjected to a time-kill assay to further evaluate this synergistic interaction. Dose-dependent inhibition by disulfiram was assessed to determine IC50 for NDM-1, IMP-7, VIM-2 and KPC-2. Further, to test the efficacy of meropenem monotherapy and meropenem in combination with disulfiram against NDM- and IMP-harbouring A. baumannii, an experimental model of systemic infection and pneumonia was developed using BALB/c female mice.

RESULTS

Chequerboard and antibiotic reversal assay displayed a synergistic interaction against MBL-expressing A. baumannii strains with 4- to 32-fold reduction in MICs of meropenem. In time-kill analysis, meropenem and disulfiram exhibited synergy against NDM- and IMP-producing carbapenem-resistant A. baumannii (CRAb) isolates. In vitro dose-dependent inhibition analysis showed that disulfiram inhibits NDM-1 and IMP-7 with IC50 values of 1.5 ± 0.6 and 16.25 ± 1.6 μM, respectively, with slight or no inhibition of VIM-2 (<20%) and KPC-2. The combination performed better in the clearance of bacterial load from the liver and spleen of mice infected with IMP-expressing CRAb. In the pneumonia model, the combination significantly decreased the bacterial burden of NDM producers compared with monotherapy.

CONCLUSIONS

These results strongly suggest that the combination of disulfiram and meropenem represents an effective treatment option for NDM- and IMP-associated CRAb infections.

Pharmacological evaluation of disulfiram analogs as antimicrobial agents and their application as inhibitors of fosB-mediated fosfomycin resistance

Disulfide analogs of the alcohol sobriety medication disulfiram (Antabuse^™) were evaluated for antimicrobial activity. Structure-activity relationship analyses of MIC data obtained for MRSA and other pathogenic organisms revealed correlations between the lipophilicity and bulkiness of the substituents. Analogs conferring optimal anti-MRSA activity contained S-octyl disulfides and either N,N-dimethyl- or N-pyrrolidine dithiocarbamate substituents. Additional testing revealed that both disulfiram and its S-octyl derivative are capable of sensitizing MRSA to the bactericidal effects of fosfomycin. Mechanistic studies established that the compounds decrease intracellular levels of the fosB cofactor bacillithiol through a thiol-disulfide exchange reaction. The altered MRSA susceptibility was thereby attributed to a depleted cellular bacillithiol pool available for fosB inactivation of fosfomycin.

The antimicrobial and immunomodulatory effects of Ionophores for the treatment of human infection

Ionophores are a diverse class of synthetic and naturally occurring ion transporter compounds which demonstrate both direct and in-direct antimicrobial properties against a broad panel of bacterial, fungal, viral and parasitic pathogens. In addition, ionophores can regulate the host-immune response during communicable and non-communicable disease states. Although the clinical use of ionophores such as Amphotericin B, Bedaquiline and Ivermectin highlight the utility of ionophores in modern medicine, for many other ionophore compounds issues surrounding toxicity, bioavailability or lack of in vivo efficacy studies have hindered clinical development. The antimicrobial and immunomodulating properties of a range of compounds with characteristics of ionophores remain largely unexplored. As such, ionophores remain a latent therapeutic avenue to address both the global burden of antimicrobial resistance, and the unmet clinical need for new antimicrobial therapies. This review will provide an overview of the broad-spectrum antimicrobial and immunomodulatory properties of ionophores, and their potential uses in clinical medicine for combatting infection.

From Genome to Drugs: New Approaches in Antimicrobial Discovery

Decades of successful use of antibiotics is currently challenged by the emergence of increasingly resistant bacterial strains. Novel drugs are urgently required but, in a scenario where private investment in the development of new antimicrobials is declining, efforts to combat drug-resistant infections become a worldwide public health problem. Reasons behind unsuccessful new antimicrobial development projects range from inadequate selection of the molecular targets to a lack of innovation. In this context, increasingly available omics data for multiple pathogens has created new drug discovery and development opportunities to fight infectious diseases. Identification of an appropriate molecular target is currently accepted as a critical step of the drug discovery process. Here, we review how diverse layers of multi-omics data in conjunction with structural/functional analysis and systems biology can be used to prioritize the best candidate proteins. Once the target is selected, virtual screening can be used as a robust methodology to explore molecular scaffolds that could act as inhibitors, guiding the development of new drug lead compounds. This review focuses on how the advent of omics and the development and application of bioinformatics strategies conduct a "big-data era" that improves target selection and lead compound identification in a cost-effective and shortened timeline.

Antibacterial Effects of Disulfiram in Helicobacter pylori

Background

Helicobacter pylori infection poses a risk of the occurrence of gastrointestinal diseases, such as gastric cancer. Its incidence rate is significantly reduced by eradication, and thereby, eradication therapy is generally performed. Disulfiram is an oral prescription drug mainly used for the treatment of alcohol dependence. In recent years, reports have been made on its anticancer and antibacterial effects, and thus, it has recently become an interesting subject. This study aimed to examine the antibacterial activity of disulfiram, investigate the presence or absence of its antibacterial activity on H. pylori, and determine whether it could be a new bactericidal drug against drug-resistant H. pylori.

Materials and Methods

Drug-sensitive strains of H. pylori and amoxicillin-resistant, clarithromycin-resistant, and metronidazole-resistant strains were used, and a growth inhibition test of H. pylori using disulfiram was performed. Furthermore, the expression of urease, vacuolating cytotoxin A (VacA), and CagA, the virulence proteins of H. pylori, was quantitatively analyzed using the Western blotting method. In addition, for H. pylori used in this study, the 16SrDNA sequence, a ribosomal gene involved in protein production, was analyzed to examine the presence or absence of gene mutation.

Results

Disulfiram suppressed the growth of 7 out of 12 H. pylori strains at 1 µg/mL, and no correlation was observed between their susceptibility/resistance to current eradication antimicrobial drugs and disulfiram resistance. Disulfiram reduced the expression levels of urease, VacA, and CagA proteins. H. pylori, which showed resistance to disulfiram, tended to have fewer gene deletions/insertions in the 16S rDNA sequence; however, no specific mutation was detected.

Conclusion

Disulfiram has a bactericidal effect on H. pylori at low concentrations, suggesting that it can be used as a supplement for current H. pylori eradication drugs.

Advantages and disadvantages of disulfiram coadministered with popular addictive substances

Disulfiram (DSF) is a well-known anti-alcohol agent that inhibits aldehyde dehydrogenase and results in extreme 'hangover' symptoms when consumed with alcohol. This drug, however, has been suggested as useful in other forms of drug addiction due to its beneficial potential in both drug abuse reduction and withdrawal. However, among other drugs used in alcohol dependence, it carries the greatest risk of pharmacological interactions. Concomitant use of DSF and central nervous system stimulants usually leads to harmful, undesirable effects. To date, there is still limited data regarding the detailed safety profile of DSF as a concomitant drug. In this review article, we outline the current state of knowledge about DSF, its broad pharmacological action, as well as therapeutic effects, with a particular emphasis on the molecular understanding of its potential pharmacodynamic interactions with common addictive substances (e.g., alcohol, cocaine, cannabinoids, opioids) supported by relevant examples.

Drug Repurposing of the Alcohol Abuse Medication Disulfiram as an Anti-Parasitic Agent

Parasitic infections contribute significantly to worldwide morbidity and mortality. Antibiotic treatment is essential for managing patients infected with these parasites since control is otherwise challenging and there are no vaccines available for prevention. However, new antimicrobial therapies are urgently needed as significant problems exist with current treatments such as drug resistance, limited options, poor efficacy, as well as toxicity. This situation is made worse by the challenges of drug discovery and development which is costly especially for non-profitable infectious diseases, time-consuming, and risky with a high failure rate. Drug repurposing which involves finding new use for existing drugs may help to more rapidly identify therapeutic candidates while drastically cutting costs of drug research and development. In this perspective article, we discuss the importance of drug repurposing, review disulfiram pharmacology, and highlight emerging data that supports repurposing disulfiram as an anti-parasitic, exemplified by the major diarrhea-causing parasite Entamoeba histolytica.

The revival of dithiocarbamates: from pesticides to innovative medical treatments

Dithiocarbamates (DTCs) have been used for various applications, including as hardening agents in rubber manufacturing, as fungicide in agriculture, and as medications to treat alcohol misuse disorder. The multi-faceted effects of DTCs rely mainly on metal binding abilities and a high reactivity with thiol groups. Therefore, the list of potential applications is still increasing, exemplified by the US Food and Drug Administration approval of disulfiram (Antabuse) and its metabolite diethyldithiocarbamate in clinical trials against cancer, human immunodeficiency virus, and Lyme disease, as well as new DTC-related compounds that have been synthesized to target diseases with unmet therapeutic needs. In this review, we will discuss the latest progress of DTCs as anti-cancer agents and provide a summary of the mechanisms of action. We will explain the expansion of DTCs' activity in the fields of microbiology, neurology, cardiology, and ophthalmology, thereby providing evidence for the important role and therapeutic potential of DTCs as innovative medical treatments.

Co-treatment with disulfiram and glycyrrhizic acid suppresses the inflammatory response of chondrocytes

Background

Osteoarthritis (OA) is a kind of systemic musculoskeletal disorder and a most important factor for causing disability and physical painfulness. Nevertheless, due to the fact that OA can be triggered by multiple etiological factors, this disease is hard to be cured. Therefore, it is of great necessity for us to find novel targets or drugs for OA treatment.

Materials and methods

The chondrocytes were treated with lipopolysaccharide (LPS) and adenosine triphosphate (ATP) to induce pyroptosis in OA. The cell proliferation was detected by Cell Counting Kit-8 assay (CCK-8 assay). Enzyme-linked immunosorbent assay (ELISA) was used for the detection of pyroptosis-related inflammatory factors. Then, the antagonists for gasdermin D (GSDMD) (disulfiram) and high mobility group box 1 (HMGB1) (glycyrrhizic acid) were used to treat the cell model to observe the effects of disulfiram and glycyrrhizic acid on the proliferation of chondrocytes in OA. The protein levels of pyroptosis-related inflammatory factors were measured by western blot, and the levels of aldehyde dehydrogenase (ALDH) and reactive oxygen species (ROS) were measured by corresponding commercial kits.

Results

After chondrocytes were induced by LPS and ATP, the cell proliferation was decreased and the expressions of pyroptosis-related inflammatory factors were increased. Disulfiram and glycyrrhizic acid treatment led to enhanced cell proliferation and increased expressions of pyroptosis-related inflammatory factors, while disulfiram showed better alleviative effects on the inflammation in chondrocytes in OA. However, co-treatment with disulfiram at a high concentration and glycyrrhizic acid did not result in higher proliferation of chondrocytes and alleviated inflammation, but led to oxidative stress.

Conclusion

In conclusion, co-treatment with disulfiram and glycyrrhizic acid at a standard concentration suppresses the inflammatory response of chondrocytes, which may provide guidance for the use of the drugs in the treatment of OA.

Repurposing Disulfiram (Tetraethylthiuram Disulfide) as a Potential Drug Candidate against Borrelia burgdorferi In Vitro and In Vivo

Lyme disease caused by the Borrelia burgdorferi (Bb or B. burgdorferi) is the most common vector-borne, multi-systemic disease in the USA. Although most Lyme disease patients can be cured with a course of the first line of antibiotic treatment, some patients are intolerant to currently available antibiotics, necessitating the development of more effective therapeutics. We previously found several drugs, including disulfiram, that exhibited effective activity against B. burgdorferi. In the current study, we evaluated the potential of repurposing the FDA-approved drug, disulfiram for its borreliacidal activity. Our results indicate disulfiram has excellent borreliacidal activity against both the log and stationary phase B. burgdorferi sensu stricto B31 MI. Treatment of mice with disulfiram eliminated the B. burgdorferi sensu stricto B31 MI completely from the hearts and urinary bladder by day 28 post infection. Moreover, disulfiram-treated mice showed reduced expressions of inflammatory markers, and thus they were protected from histopathology and cardiac organ damage. Furthermore, disulfiram-treated mice showed significantly lower amounts of total antibody titers (IgM and IgG) at day 21 and total IgG2b at day 28 post infection. FACS analysis of lymph nodes revealed a decrease in the percentage of CD19+ B cells and an increase in total percentage of CD3+ T cells, CD3+ CD4+ T helpers, and naive and effector memory cells in disulfiram-treated mice. Together, our findings suggest that disulfiram has the potential to be repurposed as an effective antibiotic for treating Lyme disease.

Comparative study of the effects of ziram and disulfiram on human monocyte-derived macrophage functions and polarization: involvement of zinc

Ziram, a zinc dithiocarbamate is widely used worldwide as a fungicide in agriculture. In order to investigate ziram-induced changes in macrophage functions and polarization, human monocytes-derived macrophages in culture were treated with ziram at 0.01-10 μmol.L^-1 for 4-24 h. To characterize zinc involvement in these changes, we also determined the effects of disulfiram alone (dithiocarbamate without zinc) or in co-incubation with ZnSO₄. We have shown that ziram and disulfiram at 0.01 μmol.L^-1 increased zymosan phagocytosis. In contrast, ziram at 10 μmol.L^-1 completely inhibited this phagocytic process, the oxidative burst triggered by zymosan and the production of TNF-α, IL-1β, IL-6, and CCL2 triggered by LPS. Disulfiram had the same effects on these macrophages functions only when combined with zinc (10 μmol.L^-1). In contrast, at 10 μmol.L^-1 ziram and zinc associated-disulfiram induced expression of several antioxidants genes HMOX1, SOD2, and catalase, which could suggest the induction of oxidative stress. This oxidative stress could be involved in the increase in late apoptosis induced by ziram (10 μmol.L^-1) and zinc associated-disulfiram. Concerning gene expression profiles of membrane markers of macrophage polarization, ziram at 10 μmol.L^-1 had two opposite effects. It inhibited the gene expression of M2 markers (CD36, CD163) in the same way as the disulfiram-zinc co-treatment. Conversely, ziram induced gene expression of other M2 markers CD209, CD11b, and CD16 in the same way as treatment with zinc alone. Disulfiram-zinc association had no significant effects on these markers. These results taken together show that ziram via zinc modulates macrophages to M2-like anti-inflammatory phenotype which is often associated with various diseases.

Isobologram Analysis: A Comprehensive Review of Methodology and Current Research

Drug combination is a common method for clinical disease treatment. Whether the combination of drugs is reasonable often affects the result of the disease treatment. Many methods have been used to evaluate interaction between drugs to date. Isobologram analysis has been mathematically proven and widely used to evaluate drug interactions. In this paper, the principle of isobologram analysis and its application in drug interaction evaluation are summarized. The applications of the similar cotoxicity coefficient and fractional inhibitory concentration index in the evaluation of drug interaction are also reviewed. This work is expected to evaluate the effect of formulations scientifically and provide scientific judgment standards for the development of formulations and clinical drug compatibility.

Gut microbiome: An intermediary to neurotoxicity

There is growing recognition that the gut microbiome is an important regulator for neurological functions. This review provides a summary on the role of gut microbiota in various neurological disorders including neurotoxicity induced by environmental stressors such as drugs, environmental contaminants, and dietary factors. We propose that the gut microbiome remotely senses and regulates CNS signaling through the following mechanisms: 1) intestinal bacteria-mediated biotransformation of neurotoxicants that alters the neuro-reactivity of the parent compounds; 2) altered production of neuro-reactive microbial metabolites following exposure to certain environmental stressors; 3) bi-directional communication within the gut-brain axis to alter the intestinal barrier integrity; and 4) regulation of mucosal immune function. Distinct microbial metabolites may enter systemic circulation and epigenetically reprogram the expression of host genes in the CNS, regulating neuroinflammation, cell survival, or cell death. We will also review the current tools for the study of the gut-brain axis and provide some suggestions to move this field forward in the future.