Drug Repositioning

Drug repurposing: an alternative strategy to treat COVID-19

Mon, 2021-07-12 06:00

Curr Pharm Biotechnol. 2021 Jul 9. doi: 10.2174/1389201022666210709141320. Online ahead of print.

ABSTRACT

In order to curve the ongoing trend of the COVID-19 pandemic and save more lives, effective treatments against COVID-19 are urgently needed. Comparing to developing new drugs, which may take too much time, it's more efficient and cost-effective to repurpose existing drugs in the treatment of COVID-19. Fortunately, some of the shared features of COVID-19 and other well-known diseases make it possible to use old strategies to combat this new challenge. In this paper, we reviewed various possible strategies of drug repurposing in the treatment of COVID-19 and explored the possible scientific mechanisms behind each strategy.

PMID:34250872 | DOI:10.2174/1389201022666210709141320

Categories: Literature Watch

Identification of Prognostic Signature and Gliclazide as Candidate Drugs in Lung Adenocarcinoma

Mon, 2021-07-12 06:00

Front Oncol. 2021 Jun 24;11:665276. doi: 10.3389/fonc.2021.665276. eCollection 2021.

ABSTRACT

BACKGROUND: Lung adenocarcinoma (LUAD) is the most common pathological type of lung cancer, with high incidence and mortality. To improve the curative effect and prolong the survival of patients, it is necessary to find new biomarkers to accurately predict the prognosis of patients and explore new strategy to treat high-risk LUAD.

METHODS: A comprehensive genome-wide profiling analysis was conducted using a retrospective pool of LUAD patient data from the previous datasets of Gene Expression Omnibus (GEO) including GSE18842, GSE19188, GSE40791 and GSE50081 and The Cancer Genome Atlas (TCGA). Differential gene analysis and Cox proportional hazard model were used to identify differentially expressed genes with survival significance as candidate prognostic genes. The Kaplan-Meier with log-rank test was used to assess survival difference. A risk score model was developed and validated using TCGA-LUAD and GSE50081. Additionally, The Connectivity Map (CMAP) was used to predict drugs for the treatment of LUAD. The anti-cancer effect and mechanism of its candidate drugs were studied in LUAD cell lines.

RESULTS: We identified a 5-gene signature (KIF20A, KLF4, KRT6A, LIFR and RGS13). Risk Score (RS) based on 5-gene signature was significantly associated with overall survival (OS). Nomogram combining RS with clinical pathology parameters could potently predict the prognosis of patients with LUAD. Moreover, gliclazide was identified as a candidate drug for the treatment of high-RS LUAD. Finally, gliclazide was shown to induce cell cycle arrest and apoptosis in LUAD cells possibly by targeting CCNB1, CCNB2, CDK1 and AURKA.

CONCLUSION: This study identified a 5-gene signature that can predict the prognosis of patients with LUAD, and Gliclazide as a potential therapeutic drug for LUAD. It provides a new direction for the prognosis and treatment of patients with LUAD.

PMID:34249701 | PMC:PMC8264429 | DOI:10.3389/fonc.2021.665276

Categories: Literature Watch

Something Old, Something New: Ion Channel Blockers as Potential Anti-Tuberculosis Agents

Mon, 2021-07-12 06:00

Front Immunol. 2021 Jun 24;12:665785. doi: 10.3389/fimmu.2021.665785. eCollection 2021.

ABSTRACT

Tuberculosis (TB) remains a challenging global health concern and claims more than a million lives every year. We lack an effective vaccine and understanding of what constitutes protective immunity against TB to inform rational vaccine design. Moreover, treatment of TB requires prolonged use of multi-drug regimens and is complicated by problems of compliance and drug resistance. While most Mycobacterium tuberculosis (Mtb) bacilli are quickly killed by the drugs, the prolonged course of treatment is required to clear persistent drug-tolerant subpopulations. Mtb's differential sensitivity to drugs is, at least in part, determined by the interaction between the bacilli and different host macrophage populations. Therefore, to design better treatment regimens for TB, we need to understand and modulate the heterogeneity and divergent responses that Mtb bacilli exhibit within macrophages. However, developing drugs de-novo is a long and expensive process. An alternative approach to expedite the development of new TB treatments is to repurpose existing drugs that were developed for other therapeutic purposes if they also possess anti-tuberculosis activity. There is growing interest in the use of immune modulators to supplement current anti-TB drugs by enhancing the host's antimycobacterial responses. Ion channel blocking agents are among the most promising of the host-directed therapeutics. Some ion channel blockers also interfere with the activity of mycobacterial efflux pumps. In this review, we discuss some of the ion channel blockers that have shown promise as potential anti-TB agents.

PMID:34248944 | PMC:PMC8264357 | DOI:10.3389/fimmu.2021.665785

Categories: Literature Watch

A Computational Approach Identified Andrographolide as a Potential Drug for Suppressing COVID-19-Induced Cytokine Storm

Mon, 2021-07-12 06:00

Front Immunol. 2021 Jun 24;12:648250. doi: 10.3389/fimmu.2021.648250. eCollection 2021.

ABSTRACT

BACKGROUND: The newly identified betacoronavirus SARS-CoV-2 is the causative pathogen of the coronavirus disease of 2019 (COVID-19) that killed more than 3.5 million people till now. The cytokine storm induced in severe COVID-19 patients causes hyper-inflammation, is the primary reason for respiratory and multi-organ failure and fatality. This work uses a rational computational strategy to identify the existing drug molecules to target host pathways to reduce the cytokine storm.

RESULTS: We used a "host response signature network" consist of 36 genes induced by SARS-CoV-2 infection and associated with cytokine storm. In order to attenuate the cytokine storm, potential drug molecules were searched against "host response signature network". Our study identified that drug molecule andrographolide, naturally present in a medicinal plant Andrographis paniculata, has the potential to bind with crucial proteins to block the TNF-induced NFkB1 signaling pathway responsible for cytokine storm in COVID-19 patients. The molecular docking method showed the binding of andrographolide with TNF and covalent binding with NFkB1 proteins of the TNF signaling pathway.

CONCLUSION: We used a rational computational approach to repurpose existing drugs targeting host immunomodulating pathways. Our study suggests that andrographolide could bind with TNF and NFkB1 proteins, block TNF-induced cytokine storm in COVID-19 patients, and warrant further experimental validation.

PMID:34248936 | PMC:PMC8264290 | DOI:10.3389/fimmu.2021.648250

Categories: Literature Watch

Serratiopeptidase, A Serine Protease Anti-Inflammatory, Fibrinolytic, and Mucolytic Drug, Can Be a Useful Adjuvant for Management in COVID-19

Mon, 2021-07-12 06:00

Front Pharmacol. 2021 Jun 24;12:603997. doi: 10.3389/fphar.2021.603997. eCollection 2021.

NO ABSTRACT

PMID:34248612 | PMC:PMC8265778 | DOI:10.3389/fphar.2021.603997

Categories: Literature Watch

<em>In Silico</em> Exploration of Phytoconstituents From <em>Phyllanthus emblica</em> and <em>Aegle marmelos</em> as Potential Therapeutics Against SARS-CoV-2 RdRp

Mon, 2021-07-12 06:00

Bioinform Biol Insights. 2021 Jun 24;15:11779322211027403. doi: 10.1177/11779322211027403. eCollection 2021.

ABSTRACT

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) worldwide has increased the importance of computational tools to design a drug or vaccine in reduced time with minimum risk. Earlier studies have emphasized the important role of RNA-dependent RNA polymerase (RdRp) in SARS-CoV-2 replication as a potential drug target. In our study, comprehensive computational approaches were applied to identify potential compounds targeting RdRp of SARS-CoV-2. To study the binding affinity and stability of the phytocompounds from Phyllanthus emblica and Aegel marmelos within the defined binding site of SARS-CoV-2 RdRp, they were subjected to molecular docking, 100 ns molecular dynamics (MD) simulation followed by post-simulation analysis. Furthermore, to assess the importance of features involved in the strong binding affinity, molecular field-based similarity analysis was performed. Based on comparative molecular docking and simulation studies of the selected phytocompounds with SARS-CoV-2 RdRp revealed that EBDGp possesses a stronger binding affinity (-23.32 kcal/mol) and stability than other phytocompounds and reference compound, Remdesivir (-19.36 kcal/mol). Molecular field-based similarity profiling has supported our study in the validation of the importance of the presence of hydroxyl groups in EBDGp, involved in increasing its binding affinity toward SARS-CoV-2 RdRp. Molecular docking and dynamic simulation results confirmed that EBDGp has better inhibitory potential than Remdesivir and can be an effective novel drug for SARS-CoV-2 RdRp. Furthermore, binding free energy calculations confirmed the higher stability of the SARS-CoV-2 RdRp-EBDGp complex. These results suggest that the EBDGp compound may emerge as a promising drug against SARS-CoV-2 and hence requires further experimental validation.

PMID:34248355 | PMC:PMC8236766 | DOI:10.1177/11779322211027403

Categories: Literature Watch

Artificial intelligence and the future of life sciences

Sat, 2021-07-10 06:00

Drug Discov Today. 2021 Jul 7:S1359-6446(21)00308-1. doi: 10.1016/j.drudis.2021.07.002. Online ahead of print.

ABSTRACT

Over the past few decades, the number of health and 'omics-related data generated and stored has grown exponentially. Patient information can be collected in real time and explored using various artificial intelligence (AI) tools in clinical trials; mobile devices can also be used to improve aspects of both the diagnosis and treatment of diseases. In addition, AI can be used in the development of new drugs or for drug repurposing, in the faster diagnosis and more efficient treatment of various diseases, as well as to design data-driven hypotheses for scientists. In this review, we discuss how AI is starting to revolutionize the life sciences sector.

PMID:34245910 | DOI:10.1016/j.drudis.2021.07.002

Categories: Literature Watch

Published anti-SARS-CoV-2 in vitro hits share common mechanisms of action that synergize with antivirals

Sat, 2021-07-10 06:00

Brief Bioinform. 2021 Jul 9:bbab249. doi: 10.1093/bib/bbab249. Online ahead of print.

ABSTRACT

The global efforts in the past year have led to the discovery of nearly 200 drug repurposing candidates for COVID-19. Gaining more insights into their mechanisms of action could facilitate a better understanding of infection and the development of therapeutics. Leveraging large-scale drug-induced gene expression profiles, we found 36% of the active compounds regulate genes related to cholesterol homeostasis and microtubule cytoskeleton organization. Following bioinformatics analyses revealed that the expression of these genes is associated with COVID-19 patient severity and has predictive power on anti-SARS-CoV-2 efficacy in vitro. Monensin, a top new compound that regulates these genes, was further confirmed as an inhibitor of SARS-CoV-2 replication in Vero-E6 cells. Interestingly, drugs co-targeting cholesterol homeostasis and microtubule cytoskeleton organization processes more likely present a synergistic effect with antivirals. Therefore, potential therapeutics could be centered around combinations of targeting these processes and viral proteins.

PMID:34245241 | DOI:10.1093/bib/bbab249

Categories: Literature Watch

A fast protein binding site comparison algorithm for proteome-wide protein function prediction and drug repurposing

Sat, 2021-07-10 06:00

Proteins. 2021 Jul 10. doi: 10.1002/prot.26176. Online ahead of print.

ABSTRACT

The expansion of three-dimensional protein structures and enhanced computing power have significantly facilitated our understanding of protein sequence/structure/function relationships. A challenge in structural genomics is to predict the function of uncharacterized proteins. Protein function deconvolution based on global sequence or structural homology is impracticable when a protein relates to no other proteins with known function, and in such cases, functional relationships can be established by detecting their local ligand binding site similarity. Here, we introduce a sequence order-independent comparison algorithm, PocketShape, for structural proteome-wide exploration of protein functional site by fully considering the geometry of the backbones, orientation of the sidechains and physiochemical properties of the pocket-lining residues. PocketShape is efficient in distinguishing similar from dissimilar ligand binding site pairs by retrieving 99.3% of the similar pairs while rejecting 100% of the dissimilar pairs on a dataset containing 1538 binding site pairs. This method successfully classifies 83 enzyme structures with diverse functions into 12 clusters, which is highly in accordance with the actual SCOP classification. PocketShape also achieves superior performances than other methods in protein profiling based on experimental data. Potential new applications for representative SARS-CoV-2 drugs Remdesivir and 11a are predicted. The high accuracy and time-efficient characteristics of PocketShape will undoubtedly make it a promising complementary tool for proteome-wide protein function inference and drug repurposing study. This article is protected by copyright. All rights reserved.

PMID:34245187 | DOI:10.1002/prot.26176

Categories: Literature Watch

Cost-Based Price Calculation of Mexiletine for Nondystrophic Myotonia

Sat, 2021-07-10 06:00

Value Health. 2021 Jul;24(7):925-929. doi: 10.1016/j.jval.2021.02.004. Epub 2021 Apr 10.

ABSTRACT

OBJECTIVES: Mexiletine is a long-known drug used for the treatment of arrhythmias and repurposed in the 1980s for patients with nondystrophic myotonia (NDM). Recently, the price of mexiletine in Europe increased significantly after registration as an orphan drug for NDM. This led to international discussions on affordability and willingness to reimburse mexiletine in the absence of background information that would justify such a price. Our objective was to calculate a cost-based price for mexiletine for adult patients with NDM based on detailed information on development costs.

METHODS: We calculated a fair price based on a cost-based pricing model for commercial mexiletine to treat adults with NDM using a recent European drug-pricing model as a framework to include actual costs incurred. Three scenarios were applied: 1 with minimum estimated costs, 1 with maximum estimated costs, and 1 with costs as if mexiletine was innovative.

RESULTS: The calculated fair price of mexiletine per patient per year (PPPY) is €452 for the minimum scenario and €1996 for the maximum scenario. By using hypothetical R&D costs used for innovative drugs, the price would be €6685 PPPY. In Europe, the list price of mexiletine ranges from €30 707-60 730 PPPY, based on 600 mg daily.

CONCLUSIONS: The current list price for mexiletine in Europe is manifold higher than any scenario of the cost-based models. Accounting for the reduced costs for clinical development in a repurposing scenario, the cost-based pricing model provides a fair commercial price range, which can be used as benchmark for pricing negotiations and/or reimbursement decisions.

PMID:34243835 | DOI:10.1016/j.jval.2021.02.004

Categories: Literature Watch

Evaluation of artemisinin derivative artemether as a fluconazole potentiator through inhibition of Pdr5

Fri, 2021-07-09 06:00

Bioorg Med Chem. 2021 Jun 25;44:116293. doi: 10.1016/j.bmc.2021.116293. Online ahead of print.

ABSTRACT

Antifungal development has gained increasing attention due to its limited armamentarium and drug resistance. Drug repurposing holds great potential in antifungal discovery. In this study, we explored the antifungal activity of artemisinin and its derivatives, dihydroartemisinin, artesunate and artemether. We identified that artemisinins can inhibit the growth of Candida albicans, and can enhance the activity of three commonly used antifungals, amphotericin B, micafungin and fluconazole (FLC), on Candida albicans growth and filamentation. Artemisinins possess stronger antifungal effect with FLC than with other antifungals. Among artemisinins, artemether exhibits the most potent antifungal activity with FLC and can recover the susceptibility of FLC-resistant clinical isolates to FLC treatment. The combinatorial antifungal activity of artemether and FLC is broad-spectrum, as it can inhibit the growth of Candida auris, Candida tropicalis, Candida parapsilosis, Saccharomyces cerevisiae and Cryptococcus neoformans. Mechanistic investigation revealed that artemether might enhance azole efficacy through disrupting the function of Pdr5, leading to intracellular accumulation of FLC. This study identified artemether as a novel FLC potentiator, providing potential therapeutic insights against fungal infection and antifungal resistance.

PMID:34243044 | DOI:10.1016/j.bmc.2021.116293

Categories: Literature Watch

Mechanisms and Molecular Targets of Artemisinin in Cancer Treatment

Fri, 2021-07-09 06:00

Cancer Invest. 2021 Jul 9:1-23. doi: 10.1080/07357907.2021.1954190. Online ahead of print.

ABSTRACT

The major problems with cancer therapy are drug-induced side effects. There is an urgent need for safe anti-tumor drugs. Artemisinin is a Chinese herbal remedy for malaria with efficacy and safety. However, several studies reported that artemisinin causes neurotoxicity and cardiotoxicity in animal models. Recently, nanostructured drug delivery systems have been designed to improve therapeutic efficacy and reduce toxicity. Artemisinin has been reported to show anticancer properties. The anticancer effects of artemisinin appear to be mediated by inducing cell cycle arrest, promoting ferroptosis and autophagy, inhibiting cell metastasis. Therefore, the review is to concentrate on mechanisms and molecular targets of artemisinin as anti-tumor agents. We believe these will be important topics in realizing the potential of artemisinin and its derivatives as potent anticancer agents.

PMID:34241563 | DOI:10.1080/07357907.2021.1954190

Categories: Literature Watch

Triazavirin might be the new hope to fight Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2)

Fri, 2021-07-09 06:00

Ceska Slov Farm. 2021 Spring;70(1):18-25.

ABSTRACT

Since the beginning of the outbreak, a large number of clinical trials have been registered worldwide, and thousands of drugs have been investigated to face new health emergency of highly contagious COVID-19 caused by the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2). Drug repurposing, i.e., utilizing an approved drug for a different indication, offers a time- and cost-efficient alternative for making new (relevant) therapies available to physicians and patients. Considering given strategy, many approved and investigational antiviral compounds, alone or in various relevant combinations, used in the past to fight Severe Acute Respiratory Syndrome Coronavirus-1, Middle East Respiratory Syndrome Coronavirus, Human Immunodeficiency Virus type 1, or Influenza viruses are being evaluated against the SARS-CoV-2. Triazavirin (TZV), a non-toxic broad--spectrum antiviral compound, is efficient against various strains of the Influenza A virus (Influenza Virus A, Orthomyxoviridae), i.e., swine flu (H1N1, or H3N2), avian influenza (H5N1, H5N2, H9N2, or highly pathogenic H7N3 strain), Influenza B virus (Influenza Virus B, Orthomyxoviridae), Respiratory Syncytial Virus (Orthopneumovirus, Pneumoviridae), Tick-Borne Encephalitis Virus (known as Forest-Spring Encephalitis Virus; Flavivirus, Flaviviridae), West Nile Virus (Flavivirus, Flavaviridae), Rift Valley Fever Virus (Phlebovirus, Bunyaviridae), and Herpes viruses (Simplexviruses, Herpesviridae) as well. In regard to COVID-19, the molecule probably reduced inflammatory reactions, thus limiting the damage to vital organs and reducing the need for therapeutic support, respectively. In addition, in silico computational methods indicated relatively satisfactory binding affinities of the TZV ligand to both structural (E)- and (S)-proteins, non-structural 3-chymotrypsin-like protease (3-CLpro) of SARS-CoV-2 as well as human angiotensin-I converting enzyme-2 (ACE-2). The interactions between TZV and given viral structures or the ACE-2 receptor for SARS-CoV-2 might effectively block both the entry of the pathogen into a host cell and its replication. Promising treatment patterns of COVID-19 positive patients might be also based on a suitable combination of a membrane fusion inhibitor (umifenovir, for example) with viral RNA synthesis and replication inhibitor (TZV).

PMID:34237949

Categories: Literature Watch

ePharmaLib: A Versatile Library of e-Pharmacophores to Address Small-Molecule (Poly-)Pharmacology

Thu, 2021-07-08 06:00

J Chem Inf Model. 2021 Jul 8. doi: 10.1021/acs.jcim.1c00135. Online ahead of print.

ABSTRACT

Bioactive compounds oftentimes bind to several target proteins, thereby exhibiting polypharmacology. Experimentally determining these interactions is however laborious, and structure-based virtual screening (SBVS) of bioactive compounds could expedite drug discovery by prioritizing hits for experimental validation. Here, we present ePharmaLib, a library of 15,148 e-pharmacophores modeled from solved structures of pharmaceutically relevant protein-ligand complexes of the screening Protein Data Bank (sc-PDB). ePharmaLib can be used for target fishing of phenotypic hits, side effect predictions, drug repurposing, and scaffold hopping. In retrospective SBVS, a good balance was obtained between computational efficiency and predictive accuracy. As a proof of concept, we carried out prospective SBVS in conjunction with a photometric assay, which inferred that the mechanism of action of neopterin (an endogenous immunomodulator) putatively stems from its inhibition (IC50 = 18 μM) of the human purine nucleoside phosphorylase. This ready-to-use library is freely available at http://www.pharmbioinf.uni-freiburg.de/epharmalib.

PMID:34236848 | DOI:10.1021/acs.jcim.1c00135

Categories: Literature Watch

Nebulization of Risedronate Sodium Microspheres for Potential Attenuation of Pulmonary Emphysema: a Promising New Insight of Alveolar Macrophage Apoptosis

Thu, 2021-07-08 06:00

AAPS PharmSciTech. 2021 Jul 7;22(5):202. doi: 10.1208/s12249-021-02078-8.

ABSTRACT

Risedronate sodium (RS) is a potent nitrogen-containing bisphosphonate which is known to induce osteoclast apoptosis. As a drug repurposing approach, the current work explored the potential of nebulizable RS-chitosan (CS) microspheres to induce alveolar macrophage apoptosis. RS-CS microspheres were assessed for lung deposition, cytotoxicity, and cellular uptake percentage in Calu-3 cells. The potential of nebulizable microspheres for treating elastase-induced emphysema in rats was investigated, compared to RS marketed oral tablets®, with respect to histopathological, immunohistochemical, and flow cytometric studies. The in vitro lung deposition pattern suggested deep alveolar deposition of RS microspheres, with respect to high FPF% and suitable MMAD (66% and 1.506 μm, respectively, at a flow rate of 28.3 L min-1). No apparent cytotoxicity was observed, with a cell viability > 90%. The inhalation of RS-CS microspheres was suggested to inhibit airspace enlargement and lung rarefaction after elastase instillation and reduce the macrophage accumulation in alveolar parenchyma. Immunohistochemical and cytometric analyses revealed significant low expression levels of CD68 and CD11b surface markers, respectively, with significantly (P < 0.05) lower detected numbers of intact alveolar macrophages following inhalation of RS-CS microspheres. The nebulization of RS-CS microspheres could induce apoptosis in alveolar macrophages and be promisingly adopted for attenuation of pulmonary emphysema.

PMID:34235597 | DOI:10.1208/s12249-021-02078-8

Categories: Literature Watch

Drugs repurposed for COVID-19 by virtual screening of 6,218 drugs and cell-based assay

Thu, 2021-07-08 06:00

Proc Natl Acad Sci U S A. 2021 Jul 27;118(30):e2024302118. doi: 10.1073/pnas.2024302118.

ABSTRACT

The COVID-19 pandemic caused by SARS-CoV-2 is an unprecedentedly significant health threat, prompting the need for rapidly developing antiviral drugs for the treatment. Drug repurposing is currently one of the most tangible options for rapidly developing drugs for emerging and reemerging viruses. In general, drug repurposing starts with virtual screening of approved drugs employing various computational methods. However, the actual hit rate of virtual screening is very low, and most of the predicted compounds are false positives. Here, we developed a strategy for virtual screening with much reduced false positives through incorporating predocking filtering based on shape similarity and postdocking filtering based on interaction similarity. We applied this advanced virtual screening approach to repurpose 6,218 approved and clinical trial drugs for COVID-19. All 6,218 compounds were screened against main protease and RNA-dependent RNA polymerase of SARS-CoV-2, resulting in 15 and 23 potential repurposed drugs, respectively. Among them, seven compounds can inhibit SARS-CoV-2 replication in Vero cells. Three of these drugs, emodin, omipalisib, and tipifarnib, show anti-SARS-CoV-2 activities in human lung cells, Calu-3. Notably, the activity of omipalisib is 200-fold higher than that of remdesivir in Calu-3. Furthermore, three drug combinations, omipalisib/remdesivir, tipifarnib/omipalisib, and tipifarnib/remdesivir, show strong synergistic effects in inhibiting SARS-CoV-2. Such drug combination therapy improves antiviral efficacy in SARS-CoV-2 infection and reduces the risk of each drug's toxicity. The drug repurposing strategy reported here will be useful for rapidly developing drugs for treating COVID-19 and other viruses.

PMID:34234012 | DOI:10.1073/pnas.2024302118

Categories: Literature Watch

Dimethyl fumarate does not mitigate cognitive decline and β-amyloidosis in female APPPS1 mice

Wed, 2021-07-07 06:00

Brain Res. 2021 Jul 4:147579. doi: 10.1016/j.brainres.2021.147579. Online ahead of print.

ABSTRACT

INTRODUCTION: Alzheimer's disease (AD) is the leading cause of dementia and a major global health issue. Currently, only limited treatment options are available to patients. One possibility to expand the treatment repertoire is repurposing of existing drugs such as dimethyl fumarate (DMF). DMF is approved for treatment of multiple sclerosis and previous animal studies have suggested that DMF may also have a beneficial effect for the treatment of AD.

METHODS: We used an APPPS1 transgenic model of senile β-amyloidosis and treated female mice orally with DMF in two treatment paradigms (pre and post onset). We quantified learning and memory parameters, β-amyloidosis, and neuroinflammation to determine the potential of DMF as AD therapeutics.

RESULTS: Treatment with DMF had no influence on water maze performance, β-amyloid accumulation, plaque formation, microglia activation, and recruitment of immune cells to the brain. Compared to vehicle-treated animals, oral DMF treatment could not halt or retard disease progression in the mice.

DISCUSSION: /Conclusion Our results do not favour the use of DMF as treatment for AD. While our results stand in contrast to previous findings in other models, they emphasize the importance of animal model selection and suggest further studies to elucidate the mechanisms leading to conflicting results.

PMID:34233173 | DOI:10.1016/j.brainres.2021.147579

Categories: Literature Watch

Antiparasitic mebendazole (MBZ) effectively overcomes cisplatin resistance in human ovarian cancer cells by inhibiting multiple cancer-associated signaling pathways

Wed, 2021-07-07 06:00

Aging (Albany NY). 2021 Jul 7;13. doi: 10.18632/aging.203232. Online ahead of print.

ABSTRACT

Ovarian cancer is the third most common cancer and the second most common cause of gynecologic cancer death in women. Its routine clinical management includes surgical resection and systemic therapy with chemotherapeutics. While the first-line systemic therapy requires the combined use of platinum-based agents and paclitaxel, many ovarian cancer patients have recurrence and eventually succumb to chemoresistance. Thus, it is imperative to develop new strategies to overcome recurrence and chemoresistance of ovarian cancer. Repurposing previously-approved drugs is a cost-effective strategy for cancer drug discovery. The antiparasitic drug mebendazole (MBZ) is one of the most promising drugs with repurposing potential. Here, we investigate whether MBZ can overcome cisplatin resistance and sensitize chemoresistant ovarian cancer cells to cisplatin. We first established and characterized two stable and robust cisplatin-resistant (CR) human ovarian cancer lines and demonstrated that MBZ markedly inhibited cell proliferation, suppressed cell wounding healing/migration, and induced apoptosis in both parental and CR cells at low micromole range. Mechanistically, MBZ was revealed to inhibit multiple cancer-related signal pathways including ELK/SRF, NFKB, MYC/MAX, and E2F/DP1 in cisplatin-resistant ovarian cancer cells. We further showed that MBZ synergized with cisplatin to suppress cell proliferation, induce cell apoptosis, and blunt tumor growth in xenograft tumor model of human cisplatin-resistant ovarian cancer cells. Collectively, our findings suggest that MBZ may be repurposed as a synergistic sensitizer of cisplatin in treating chemoresistant human ovarian cancer, which warrants further clinical studies.

PMID:34232919 | DOI:10.18632/aging.203232

Categories: Literature Watch

Neuromodulatory effects of SARS-CoV2 infection: Possible therapeutic targets

Wed, 2021-07-07 06:00

Expert Opin Ther Targets. 2021 Jul 7. doi: 10.1080/14728222.2021.1953475. Online ahead of print.

ABSTRACT

Although SARS-CoV-2 primarily manifests in the form of respiratory symptoms, emerging evidence suggests that the disease is associated with numerous neurological complications such as stroke and Guillain-Barre syndrome. Hence, further research is necessary to seek possible therapeutic targets in the CNS for effective management of these complications.Areas covered: This review examines the neurological complications associated with SARS-CoV-2 infections and the possible routes of infection. It progresses to illuminate the possible therapeutic targets for effective management of these neuromodulatory effects and the repurposing of drugs that could serve this purpose. To this end, literature from the year 1998-2021 was derived from PubMed.Expert opinion: The neurological manifestations associated with COVID-19 may be related to poor prognosis and higher comorbidity. Identification of the key molecular targets in the brain that are potential indicators of the observed neuropathology, for example, inflammatory mediators, and chromatin modifiers, is key. The repurposing of existing drugs to target potential candidates could reduce the mortality attributed to these associated neurological complications.

PMID:34232801 | DOI:10.1080/14728222.2021.1953475

Categories: Literature Watch

Amiloride ameliorates muscle wasting in cancer cachexia through inhibiting tumor-derived exosome release

Wed, 2021-07-07 06:00

Skelet Muscle. 2021 Jul 6;11(1):17. doi: 10.1186/s13395-021-00274-5.

ABSTRACT

BACKGROUND: Cancer cachexia (CAC) reduces patient survival and quality of life. Developments of efficient therapeutic strategies are required for the CAC treatments. This long-term process could be shortened by the drug-repositioning approach which exploits old drugs approved for non-cachexia disease. Amiloride, a diuretic drug, is clinically used for treatments of hypertension and edema due to heart failure. Here, we explored the effects of the amiloride treatment for ameliorating muscle wasting in murine models of cancer cachexia.

METHODS: The CT26 and LLC tumor cells were subcutaneously injected into mice to induce colon cancer cachexia and lung cancer cachexia, respectively. Amiloride was intraperitoneally injected daily once tumors were formed. Cachexia features of the CT26 model and the LLC model were separately characterized by phenotypic, histopathologic and biochemical analyses. Plasma exosomes and muscle atrophy-related proteins were quantitatively analyzed. Integrative NMR-based metabolomic and transcriptomic analyses were conducted to identify significantly altered metabolic pathways and distinctly changed metabolism-related biological processes in gastrocnemius.

RESULTS: The CT26 and LLC cachexia models displayed prominent cachexia features including decreases in body weight, skeletal muscle, adipose tissue, and muscle strength. The amiloride treatment in tumor-bearing mice distinctly alleviated muscle atrophy and relieved cachexia-related features without affecting tumor growth. Both the CT26 and LLC cachexia mice showed increased plasma exosome densities which were largely derived from tumors. Significantly, the amiloride treatment inhibited tumor-derived exosome release, which did not obviously affect exosome secretion from non-neoplastic tissues or induce observable systemic toxicities in normal healthy mice. Integrative-omics revealed significant metabolic impairments in cachectic gastrocnemius, including promoted muscular catabolism, inhibited muscular protein synthesis, blocked glycolysis, and impeded ketone body oxidation. The amiloride treatment evidently improved the metabolic impairments in cachectic gastrocnemius.

CONCLUSIONS: Amiloride ameliorates cachectic muscle wasting and alleviates cancer cachexia progression through inhibiting tumor-derived exosome release. Our results are beneficial to understanding the underlying molecular mechanisms, shedding light on the potentials of amiloride in cachexia therapy.

PMID:34229732 | DOI:10.1186/s13395-021-00274-5

Categories: Literature Watch

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