Repurposing Loperamide as an Anti-Infection Drug for the Treatment of Intracellular Bacterial Pathogens

Infections caused by intracellular bacterial pathogens are difficult to treat since most antibiotics have low cell permeability and undergo rapid degradation within cells.The rapid development and dissemination of antimicrobial–resistant strains have exacerbated this dilemma.With the increasing knowledge of host–pathogen interactions,especially bacterial strategies for survival and proliferation within host cells,host-directed therapy(HDT)has attracted increased interest and has emerged as a promising antiinfection method for treating intracellular infection.Herein,we applied a cell-based screening approach to a US Food and Drug Administration(FDA)-approved drug library to identify compounds that can inhibit the intracellular replication of Salmonella Typhimurium(S.Typhimurium).This screening allowed us to identify the antidiarrheal agent loperamide(LPD)as a potent inhibitor of S.Typhimurium intracellular proliferation.LPD treatment of infected cells markedly promoted the host autophagic response and lysosomal activity.A mechanistic study revealed that the increase in host autophagy and elimination of intracellular bacteria were dependent on the high expression of glycoprotein nonmetastatic melanoma protein B(GPNMB)induced by LPD.In addition,LPD treatment effectively protected against S.Typhimurium infection in Galleria mellonella and mouse models.Thus,our study suggested that LPD may be useful for the treatment of diseases caused by intracellular bacterial pathogens.Moreover,LPD may serve as a promising lead compound for the development of anti-infection drugs based on the HDT strategy.

Drug repositioning of disulfiram induces endometrioid epithelial ovarian cancer cell death via the both apoptosis and cuproptosis pathways

Various therapeutic strategies have been developed to overcome ovarian cancer.However,the prognoses resulting from these strategies are still unclear.In the present work,we screened 54 small molecule compounds approved by the FDA to identify novel agents that could inhibit the viability of human epithelial ovarian cancer cells.Among these,we identified disulfiram(DSF),an old alcohol-abuse drug,as a potential inducer of cell death in ovarian cancer.Mechanistically,DSF treatment significantly reduced the expression of the anti-apoptosis marker Bcell lymphoma/leukemia-2(Bcl-2)and increase the expression of the apoptotic molecules Bcl2 associated X(Bax)and cleaved caspase-3 to promote human epithelial ovarian cancer cell apoptosis.Furthermore,DSF is a newly identified effective copper ionophore,thus the combination of DSF and copper was used to reduce ovarian cancer viability than DSF single treatment.Combination treatment with DSF and copper also led to the reduced expression of ferredoxin 1 and loss of Fe-S cluster proteins(biomarkers of cuproptosis).In vivo,DSF and copper gluconate significantly decreased the tumor volume and increased the survival rate in a murine ovarian cancer xenograft model.Thus,the role of DSF revealed its potential for used as a viable therapeutic agent for the ovarian cancer.

Repurposing drugs to target nonalcoholic steatohepatitis

Nonalcoholic fatty liver disease(NAFLD) is a complex disorder that has evolved in recent years as the leading global cause of chronic liver damage. The main obstacle to better disease management pertains to the lack of approved pharmacological interventions for the treatment of nonalcoholic steatohepatitis(NASH) and NASH-fibrosis-the severe histological forms. Over the past decade,tremendous advances have been made in NAFLD research, resulting in the discovery of disease mechanisms and novel therapeutic targets. Hence, a large number of pharmacological agents are currently being tested for safety and efficacy. These drugs are in the initial pharmacological phases(phase 1 and 2),which involve testing tolerability, therapeutic action, and pharmacological issues.It is thus reasonable to assume that the next generation of NASH drugs will not be available for clinical use for foreseeable future. The expected delay can be mitigated by drug repurposing or repositioning, which essentially relies on identifying and developing new uses for existing drugs. Here, we propose a drug candidate selection method based on the integration of molecular pathways of disease pathogenesis into network analysis tools that use OMICs data as well as multiples sources, including text mining from the medical literature.

Drug repurposing for cancer treatment through global propagation with a greedy algorithm in a multilayer network

Objective:Drug repurposing,the application of existing therapeutics to new indications,holds promise in achieving rapid clinical effects at a much lower cost than that of de novo drug development.The aim of our study was to perform a more comprehensive drug repurposing prediction of diseases,particularly cancers.Methods:Here,by targeting 4,096 human diseases,including 384 cancers,we propose a greedy computational model based on a heterogeneous multilayer network for the repurposing of 1,419 existing drugs in Drug Bank.We performed additional experimental validation for the dominant repurposed drugs in cancer.Results:The overall performance of the model was well supported by cross-validation and literature mining.Focusing on the top-ranked repurposed drugs in cancers,we verified the anticancer effects of 5 repurposed drugs widely used clinically in drug sensitivity experiments.Because of the distinctive antitumor effects of nifedipine(an antihypertensive agent)and nortriptyline(an antidepressant drug)in prostate cancer,we further explored their underlying mechanisms by using quantitative proteomics.Our analysis revealed that both nifedipine and nortriptyline affected the cancer-related pathways of DNA replication,the cell cycle,and RNA transport.Moreover,in vivo experiments demonstrated that nifedipine and nortriptyline significantly inhibited the growth of prostate tumors in a xenograft model.Conclusions:Our predicted results,which have been released in a public database named The Predictive Database for Drug Repurposing(PAD),provide an informative resource for discovering and ranking drugs that may potentially be repurposed for cancer treatment and determining new therapeutic effects of existing drugs.

Repurposing drugs for solid tumor treatment:focus on immune checkpoint inhibitors

Cancer remains a significant global health challenge with limited treatment options beyond systemic therapies,such as chemotherapy,radiotherapy,and molecular targeted therapy.Immunotherapy has emerged as a promising therapeutic modality but the efficacy has plateaued,which therefore provides limited benefits to patients with cancer.Identification of more effective approaches to improve patient outcomes and extend survival are urgently needed.Drug repurposing has emerged as an attractive strategy for drug development and has recently garnered considerable interest.This review comprehensively analyses the efficacy of various repurposed drugs,such as transforming growth factor-beta(TGF-β)inhibitors,metformin,receptor activator of nuclear factor-κB ligand(RANKL)inhibitors,granulocyte macrophage colony-stimulating factor(GM-CSF),thymosinα1(Tα1),aspirin,and bisphosphonate,in tumorigenesis with a specific focus on their impact on tumor immunology and immunotherapy.Additionally,we present a concise overview of the current preclinical and clinical studies investigating the potential therapeutic synergies achieved by combining these agents with immune checkpoint inhibitors.

Repositioning of clinically approved drug Bazi Bushen capsule for treatment of Alzheimer′s disease using network pharma⁃cology approach and in vitro experimental validation

OBJECTIVE To explore the new indications and key mechanism of Bazi Bushen capsule(BZBS)by network pharmacology and in vitro experiment.METHODS The potential tar⁃get profiles of the components of BZBS were pre⁃dicted.Subsequently,new indications for BZBS were predicted by disease ontology(DO)enrich⁃ment analysis and initially validated by GO and KEGG pathway enrichment analysis.Further⁃more,the therapeutic target of BZBS acting on AD signaling pathway were identified by intersec⁃tion analysis.Two Alzheimer′s disease(AD)cell models,BV-2 and SH-SY5Y,were used to pre⁃liminarily verify the anti-AD efficacy and mecha⁃nism of BZBS in vitro.RESULTS In total,1499 non-repeated ingredients were obtained from 16 herbs in BZBS formula,and 1320 BZBS targets with high confidence were predicted.Disease enrichment results strongly suggested that BZBS formula has the potential to be used in the treat⁃ment of AD.In vitro experiments showed that BZ⁃BS could significantly reduce the release of TNF-αand IL-6 and the expression of COX-2 and PSEN1 in Aβ25-35-induced BV-2 cells.BZBS reduced the apoptosis rate of Aβ25-35 induced SH-SY5Y cells,significantly increased mitochon⁃drial membrane potential,reduced the expres⁃sion of Caspase3 active fragment and PSEN1,and increased the expression of IDE.CONCLU⁃SIONS BZBS formula has a potential use in the treatment of AD,which is achieved through regu⁃lation of ERK1/2,NF-κB signaling pathways,and GSK-3β/β-catenin signaling pathway.Further⁃more,the network pharmacology technology is a feasible drug repurposing strategy to reposition new clinical use of approved TCM and explore the mechanism of action.The study lays a foun⁃dation for the subsequent in-depth study of BZBS in the treatment of AD and provides a basis for its application in the clinical treatment of AD.

Drug repurposing against coronavirus disease 2019(COVID-19):A review

Since December 2019,severe acute respiratory syndrome coronavirus 2 has been found to be the culprit in the coronavirus disease 2019(COVID-19),causing a global pandemic.Despite the existence of many vaccine programs,the number of confirmed cases and fatalities due to COVID-19 is still increasing.Furthermore,a number of variants have been reported.Because of the absence of approved anticoronavirus drugs,the treatment and management of COVID-19 has become a global challenge.Under these circumstances,drug repurposing is an effective method to identify candidate drugs with a shorter cycle of clinical trials.Here,we summarize the current status of the application of drug repurposing in COVID-19,including drug repurposing based on virtual computer screening,network pharmacology,and bioactivity,which may be a beneficial COVID-19 treatment.

Systems-level biomarkers identification and drug repositioning in colorectal cancer

Colorectal cancer(CRC)is the most commonly diagnosed fatal cancer in both women and men worldwide.CRC ranked second in mortality and third in incidence in 2020.It is difficult to diagnose CRC at an early stage as there are no clinical symptoms.Despite advances in molecular biology,only a limited number of biomarkers have been translated into routine clinical practice to predict risk,prognosis and response to treatment.In the last decades,systems biology approaches at the omics level have gained importance.Over the years,several biomarkers for CRC have been discovered in terms of disease diagnosis and prognosis.On the other hand,a few drugs are being developed and used in clinics for the treatment of CRC.However,the development of new drugs is very costly and time-consuming as the research and development takes about 10 years and more than$1 billion.Therefore,drug repositioning(DR)could save time and money by establishing new indications for existing drugs.In this review,we aim to provide an overview of biomarkers for the diagnosis and prognosis of CRC from the systems biology perspective and insights into DR approaches for the prevention or treatment of CRC.

Paracelsus Paradox and Drug Repurposing for Cancer

Dose is one of the parameters that any pharmacologist seriously considers when studying the effects of a drug.If the necessary dose to achieve a desired pharmacological effect is in a toxic or very toxic range for human use,the drug will probably fall out from further research.The concentration that a drug can reach to its target organ or cell is a direct consequence of the administered dose and its pharmacodynamic properties.Basic researchers investigate at the cellular level or eventually with xenografts.They use different concentrations of the drug in order to determine its cellular effects.However,in many cases,these concentrations require doses that are in the toxic range or well beyond any clinically achievable level.Therefore,in these cases,research is in the realm of toxicology rather than therapeutics.This paper will show some examples about this exercise in futility which is time and resource consuming but that pullulates the pages of many prestigious journals.Many seasoned researchers seem to have forgotten the Paracelsus Paradox.

An update review on drug repurposing for COVID-19

The COVID-19 global health disaster has caused more than two million deaths globally.Although,a new therapeutic molecule has not been developed for severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)as of yet.As a result,some medications that had been previously authorized for use against SARS-CoV-2 could now be given to COVID-19 patients.The use of medications to treat COVID-19 is discussed in this publication.The report also discusses the lessons learned when using combination therapy,convalescent plasma therapy,immunotherapeutic molecules,and therapeutic molecules to treat COVID-19 patients.Several beneficial outcomes were noted with anti-viral therapy and immunotherapy.The COVID-19 medicine and vaccination have undergone 9,037 clinical trials since July 2022.It may be possible to provide COVID-19 patients with a successful outcome through the short-term repurposing of an existing drug.The evaluation of potential antiviral molecules can thus lead to more clinical trials being initiated.

Drug repurposing screening and mechanism analysis based on human colorectal cancer organoids

Colorectal cancer(CRC)is a highly heterogeneous cancer and exploring novel therapeutic options is a pressing issue that needs to be addressed.Here,we established human CRC tumor-derived organoids that well represent both morphological and molecular heterogeneities of original tumors.To efficiently identify repurposed drugs for CRC,we developed a robust organoid-based drug screening system.By combining the repurposed drug library and computation-based drug prediction,335 drugs were tested and 34 drugs with anti-CRC effects were identified.More importantly,we conducted a detailed transcriptome analysis of drug responses and divided the drug response signatures into five representative patterns:differentiation induction,growth inhibition,metabolism inhibition,immune response promotion,and cell cycle inhibition.The anticancer activities of drug candidates were further validated in the established patient-derived organoids-based xenograft(PDOX)system in vivo.We found that fedratinib,trametinib,and bortezomib exhibited effective anticancer effects.Furthermore,the concordance and discordance of drug response signatures between organoids in vitro and pairwise PDOX in vivo were evaluated.Our study offers an innovative approach for drug discovery,and the representative transcriptome features of drug responses provide valuable resources for developing novel clinical treatments for CRC.

Drug repurposing screen identifies vidofludimus calcium and pyrazofurin as novel chemical entities for the development of hepatitis E interventions

Hepatitis E virus(HEV)infection can cause severe complications and high mortality,particularly in pregnant women,organ transplant recipients,individuals with pre-existing liver disease and immunosuppressed patients.However,there are still unmet needs for treating chronic HEV infections.Herein,we screened a best-in-class drug repurposing library consisting of 262 drugs/compounds.Upon screening,we identified vidofludimus calcium and pyrazofurin as novel anti-HEV entities.Vidofludimus calcium is the next-generation dihydroorotate dehydrogenase(DHODH)inhibitor in the phase 3 pipeline to treat autoimmune diseases or SARS-CoV-2 infection.Pyrazofurin selectively targets uridine monophosphate synthetase(UMPS).Their anti-HEV effects were further investigated in a range of cell culture models and human liver organoids models with wild type HEV strains and ribavirin treatment failure-associated HEV strains.Encouragingly,both drugs exhibited a sizeable therapeutic window against HEV.For instance,the IC50 value of vidofludimus calcium is 4.6–7.6-fold lower than the current therapeutic doses in patients.Mechanistically,their anti-HEV mode of action depends on the blockage of pyrimidine synthesis.Notably,two drugs robustly inhibited ribavirin treatment failure-associated HEV mutants(Y1320H,G1634R).Their combination with IFN-αresulted in synergistic antiviral activity.In conclusion,we identified vidofludimus calcium and pyrazofurin as potent candidates for the treatment of HEV infections.Based on their antiviral potency,and also the favorable safety profile identified in clinical studies,our study supports the initiation of clinical studies to repurpose these drugs for treating chronic hepatitis E.

Applications and prospects of cryo-EM in drug discovery

Drug discovery is a crucial part of human healthcare and has dramatically benefited human lifespan and life quality in recent centuries, however, it is usually time-and effort-consuming. Structural biology has been demonstrated as a powerful tool to accelerate drug development. Among different techniques, cryo-electron microscopy(cryo-EM) is emerging as the mainstream of structure determination of biomacromolecules in the past decade and has received increasing attention from the pharmaceutical industry. Although cryo-EM still has limitations in resolution, speed and throughput, a growing number of innovative drugs are being developed with the help of cryo-EM. Here, we aim to provide an overview of how cryo-EM techniques are applied to facilitate drug discovery. The development and typical workflow of cryo-EM technique will be briefly introduced, followed by its specific applications in structure-based drug design, fragment-based drug discovery, proteolysis targeting chimeras, antibody drug development and drug repurposing. Besides cryo-EM, drug discovery innovation usually involves other state-of-the-art techniques such as artificial intelligence(AI), which is increasingly active in diverse areas. The combination of cryo-EM and AI provides an opportunity to minimize limitations of cryo-EM such as automation, throughput and interpretation of mediumresolution maps, and tends to be the new direction of future development of cryo-EM. The rapid development of cryo-EM will make it as an indispensable part of modern drug discovery.

Molecules against COVID-19:An in Silico Approach for Drug Development

A large number of deaths have been caused by the severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)worldwide,turning it into a serious and momentous threat to public health.This study tends to contribute to the development of effective treatment strategies through a computational approach,investigating the mechanisms in relation to the binding and subsequent inhibition of SARS-CoV-2 ribonucleic acid(RNA)-dependent RNA polymerase(RdRp).Molecular docking was performed to screen six naturally occurring molecules with antineoplastic properties(Ellipticine,Ecteinascidin,Homoharringtonine,Dolastatin 10,Halichondrin,and Plicamycin).Absorption,distribution,metabolism,and excretion(ADME)investigation was also conducted to analyze the druglike properties of these compounds.The docked results have clearly shown binding of ligands to the SARS-CoV-2 RdRp protein.Interestingly,all ligands were found to obey Lipinski’s rule of five.These results provide a basis for repurposing and using molecules,derived from plants and animals,as a potential treatment for the coronavirus disease 2019(COVID-19)infection as they could be effective therapeutics for the same.

Trilogy of drug repurposing for developing cancer and chemotherapy-induced heart failure co-therapy agent

Chemotherapy-induced complications,particularly lethal cardiovascular diseases,pose significant challenges for cancer survivors.The intertwined adverse effects,brought by cancer and its complication,further complicate anticancer therapy and lead to diminished clinical outcomes.Simple supplementation of cardioprotective agents falls short in addressing these challenges.Developing bifunctional co-therapy agents provided another potential solution to consolidate the chemotherapy and reduce cardiac events simultaneously.Drug repurposing was naturally endowed with co-therapeutic potential of two indications,implying a unique chance in the development of bi-functional agents.Herein,we further proposed a novel“trilogy of drug repurposing”strategy that comprises function-based,targetfocused,and scaffold-driven repurposing approaches,aiming to systematically elucidate the advantages of repurposed drugs in rationally developing bi-functional agent.Through function-based repurposing,a cardioprotective agent,carvedilol(CAR),was identified as a potential neddylation inhibitor to suppress lung cancer growth.Employing target-focused SAR studies and scaffold-driven drug design,we synthesized 44 CAR derivatives to achieve a balance between anticancer and cardioprotection.Remarkably,optimal derivative 43 displayed promising bi-functional effects,especially in various self-established heart failure mice models with and without tumor-bearing.Collectively,the present study validated the practicability of the“trilogy of drug repurposing”strategy in the development of bi-functional cotherapy agents.

In Silico Screening of Potential Spike Glycoprotein Inhibitors of SARS-CoV-2 with Drug Repurposing Strategy

Objective:To select potential molecules that can target viral spike proteins,which may potentially interrupt the interaction between the human angiotension-converting enzyme 2(ACE2)receptor and viral spike protein by virtual screening.Methods:The three-dimensional(3D)-coordinate file of the receptor-binding domain(RBD)-ACE2 complex for searching a suitable docking pocket was firstly downloaded and prepared.Secondly,approximately 15,000 molecular candidates were prepared,including US Food and Drug Administration(FDA)-approved drngs from DrugBank and natural compounds from Traditional Chinese Medicine Systems Pharmacology(TCMSP),for the docking process.Then,virtual screening was performed and the binding energy in Autodock Vina was calculated.Finally,the top 20 molecules with high binding energy and their Chinese medicine(CM)herb sources were listed in this paper.Results:It was found that digitoxin,a cardiac glycoside in DrugBank and bisindigotin in TCMSP had the highest docking scores.Interestingly,two of the CM herbs containing the natural compounds that had relatively high binding scores,Forsyfh/ae frucft/s and/saf/d/s racWx,are components of Lianhua Qingwen(莲花清痕),a CM formula reportedly exerting activity against severe acute respiratory syndrome(SARS)-Cov-2.Moreover,raltegravir,an HIV integrase inhibitor,was found to have a relatively high binding score.Conclusions:A class of compounds,which are from FDA-approved drugs and CM natural compounds,that had high binding energy with RBD of the viral spike protein.Our work provides potential candidates for other researchers to identify inhibitors to prevent SARS-CoV-2 infection,and highlights the importance of CM and integrative application of CM and Western medicine on treating COVID-19.

Repurposing non-oncology small-molecule drugs to improve cancer therapy: Current situation and future directions

Drug repurposing or repositioning has been well-known to refer to the therapeutic applications of a drug for another indication other than it was originally approved for.Repurposing non-oncology small-molecule drugs has been increasingly becoming an attractive approach to improve cancer therapy,with potentially lower overall costs and shorter timelines.Several non-oncology drugs approved by FDA have been recently reported to treat different types of human cancers,with the aid of some new emerging technologies,such as omics sequencing and artificial intelligence to overcome the bottleneck of drug repurposing.Therefore,in this review,we focus on summarizing the therapeutic potential of non-oncology drugs,including cardiovascular drugs,microbiological drugs,small-molecule antibiotics,anti-viral drugs,anti-inflammatory drugs,antineurodegenerative drugs,antipsychotic drugs,antidepressants,and other drugs in human cancers.We also discuss their novel potential targets and relevant signaling pathways of these old non-oncology drugs in cancer therapies.Taken together,these inspiring findings will shed new light on repurposing more non-oncology small-molecule drugs with their intricate molecular mechanisms for future cancer drug discovery.

PIMD:An Integrative Approach for Drug Repositioning Using Multiple Characterization Fusion

The accumulation of various types of drug informatics data and computational approaches for drug repositioning can accelerate pharmaceutical research and development.However,the integration of multi-dimensional drug data for precision repositioning remains a pressing challenge.Here,we propose a systematic framework named PIMD to predict drug therapeutic properties by integrating multi-dimensional data for drug repositioning.In PIMD,drug similarity networks(DSNs)based on chemical,pharmacological,and clinical data are fused into an integrated DSN(iDSN)composed of many clusters.Rather than simple fusion,PIMD offers a systematic way to annotate clusters.Unexpected drugs within clusters and drug pairs with a high iDSN similarity score are therefore identified to predict novel therapeutic uses.PIMD provides new insights into the universality,individuality,and complementarity of different drug properties by evaluating the contribution of each property data.To test the performance of PIMD,we use chemical,pharmacological,and clinical properties to generate an iDSN.Analyses of the contributions of each drug property indicate that this iDSN was driven by all data types and performs better than other DSNs.Within the top 20 recommended drug pairs,7 drugs have been reported to be repurposed.The source code for PIMD is available at https://github.com/Sepstar/PIMD/.

Identification of anthelmintic parbendazole as a therapeutic molecule for HNSCC through connectivity map-based drug repositioning

Head and neck squamous cell carcinoma(HNSCC) is one of the most common human cancers;however, its outcome of pharmacotherapy is always very limited. Herein, we performed a batch query in the connectivity map(cMap) based on bioinformatics, queried out 35 compounds with therapeutic potential, and screened out parbendazole as a most promising compound, which had an excellent inhibitory effect on the proliferation of HNSCC cell lines. In addition, tubulin was identified as a primary target of parbendazole, and the direct binding between them was further verified. Parbendazole was further proved as an effective tubulin polymerization inhibitor, which can block the cell cycle, cause apoptosis and prevent cell migration, and it exhibited reasonable therapeutic effect and low toxicity in the in vivo and in vitro anti-tumor evaluation. Our study repositioned an anthelmintic parbendazole to treat HNSCC, which revealed a therapeutic utility and provided a new treatment option for human cancers.

A pathway profile-based method for drug repositioning

Finding new applications for existing pharmaceuticals,known as drug repositioning,is a validated strategy for resolving the problem of high expenditure but low productivity in drug discovery.Currently,the prevalent computational methods for drug repositioning are focused mainly on the similarity or relevance between known drugs based on their "features",including chemical structure,side effects,gene expression profile,and/or chemical-protein interactome.However,such drug-oriented methods may constrain the newly predicted functions to the pharmacological functional space of the existing drugs.Clinically,many drugs have been found to bind "off-target"(i.e.to receptors other than their primary targets),which can lead to undesirable effects.In this study,which integrates known drug target information,we propose a disease-oriented strategy for evaluating the relationship between drugs and disease based on their pathway profile.The basic hypothesis of this method is that drugs exerting a therapeutic effect may not only directly target the disease-related proteins but also modulate the pathways involved in the pathological process.Upon testing eight of the global best-selling drugs in 2010(each with more than three targets),the FDA(Food and Drug Administration,USA)-approved therapeutic function of each was included in the top 10 predicted indications.On average,60% of predicted results made using our method are proved by literature.This approach could be used to complement existing methods and may provide a new perspective in drug repositioning and side effect evaluation.