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1.
Int J Biol Macromol ; : 136386, 2024 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-39378921

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) remains a highly malignant cancer with a grim prognosis due to its early metastasis and resistance to current chemotherapies, such as Gemcitabine (GEM). We have previously demonstrated that cAMP exclusion by MRP4 is critical for PDAC cell proliferation, establishing this transporter as a promising prognostic marker and therapeutic target. In search for novel therapeutic options to improve GEM efficacy, we conducted a drug repositioning screening to identify potential inhibitors of cAMP transport by MRP4. Several non-steroidal anti-inflammatory drugs (NSAIDs) can inhibit the transport of certain MRP4 substrates. In this study, we assessed the efficacy of sixteen NSAIDs in inhibiting cAMP transport mediated by MRP4, identifying seven potent inhibitors based on their IC50 values. The most potent inhibitors were further tested for their effect on cell proliferation and migration. Flurbiprofen emerged as the most potent inhibitor of both MRP4-mediated cAMP transport and cell proliferation. Overexpression of MRP4 in BxPC-3 cells significantly increased GEM resistance, and co-administration of flurbiprofen with GEM markedly enhanced the latter's potency inhibiting PDAC cells proliferation. These findings position flurbiprofen as a potent inhibitor of cAMP transport by MRP4 and a promising adjunctive therapy to enhance GEM effectiveness in PDAC treatment.

2.
Virus Res ; 350: 199475, 2024 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-39362410

RESUMO

Human cytomegalovirus (HCMV), a double-stranded DNA virus from the Betaherpesvirinae subfamily, constitutes significant risks to newborns and immunocompromised individuals, potentially leading to severe neurodevelopmental disorders. The purpose of this study was to identify FDA-approved drugs that can inhibit HCMV replication through a drug repositioning approach. Using an HCMV progeny assay, verteporfin, a medication used as a photosensitizer in photodynamic therapy, was found to inhibit HCMV production in a dose-dependent manner, significantly reducing replication at concentrations as low as 0.5 µM, approximately 1/20th of the concentration used in anti-cancer research. Further analysis revealed that verteporfin did not interfere with HCMV host cell entry or nuclear transport but reduced viral mRNA and protein levels throughout the HCMV life cycle from the immediate-early stages. These results suggest that verteporfin has the potential to be rapidly and safely developed as a repurposed drug to inhibit HCMV infection.

3.
Biofouling ; : 1-15, 2024 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-39390775

RESUMO

Simvastatin had minimum inhibitory concentrations of 32 to 128 µg/mL against Klebsiella pneumoniae isolates and hindered the biofilm-formation ability of 58.54% of the isolates. It considerably diminished the bacterial cell counts in the biofilms as revealed by scanning electron microscope. Also, qRT-PCR revealed a downregulation of the biofilm genes (bcsA, wza, and luxS) by simvastatin in 48.78% of the isolates. Moreover, simvastatin has significantly improved the survival of mice and decreased the burden of bacteria in the infected lungs. Also, the histological architecture was substantially improved in the simvastatin-treated group, as the alveolar sacs and bronchioles appeared normal with minimal collagen fiber deposition. The immunohistochemical studies exposed that the TNF-α, NF-kß, and COX-2 immunostaining considerably declined in the simvastatin-treated group. Furthermore, ELISA exposed that both IL-1ß and IL-6 were considerably diminished in the lungs of the simvastatin-treated group.

4.
Cancer Med ; 13(18): e70252, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39350574

RESUMO

BACKGROUND AND AIMS: Cardiac glycosides (CGs), traditionally used for heart failure, have shown potential as anti-cancer agents. This study aims to explore their multifaceted mechanisms in cancer cell biology using proteome integral solubility alteration (PISA), focusing on the interaction with key proteins implicated in cellular metabolism and mitochondrial function. METHODS: We conducted lysate-based and intact-cell PISA assays on cancer cells treated with CGs (Digoxin, Digitoxin, Ouabain) to analyze protein solubility changes. This was followed by mass spectrometric analysis and bioinformatics to identify differentially soluble proteins (DSPs). Molecular docking simulations were performed to predict protein-CG interactions. Public data including gene expression changes upon CG treatment were re-analyzed for validation. RESULTS: The PISA assays revealed CGs' broad-spectrum interactions, particularly affecting proteins like PKM2, ANXA2, SLC16A1, GOT2 and GLUD1. Molecular docking confirmed stable interactions between CGs and these DSPs. Re-analysis of public data supported the impact of CGs on cancer metabolism and cell signaling pathways. CONCLUSION: Our findings suggest that CGs could be repurposed for cancer therapy by modulating cellular processes. The PISA data provide insights into the polypharmacological effects of CGs, warranting further exploration of their mechanisms and clinical potential.


Assuntos
Glicosídeos Cardíacos , Simulação de Acoplamento Molecular , Proteoma , Solubilidade , Humanos , Glicosídeos Cardíacos/farmacologia , Glicosídeos Cardíacos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Biologia Computacional/métodos
5.
Sci Rep ; 14(1): 23297, 2024 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-39375410

RESUMO

Drug repositioning is gaining attention as a method for developing new drugs due to its low cost, short cycle time, and high success rate. One important approach is to explore new uses for already marketed drugs. In this study, we utilized the strategy of drug repositioning, focusing on the Dan-Lou tablet. We predicted the efficacy of Dan-Lou tablet against non-small cell lung cancer based on gene expression similarity and verified it by in vitro experiments. Next, we performed further analysis and validation using network pharmacology, molecular docking and molecular dynamics. Based on the results, it was concluded that Dan-Lou tablet mainly acted through nine compounds, Quercetin, Luteolin, Scoparone, Isorhamnetin, Eugenol, Genistein, Coumestrol, Hederagenin, Succinic Acid, and mainly targeted CCL2, FEN1, TPI1, RMI2 by six pathways. This discovery not only provides a new idea for the development of Dan-Lou tablet but also provides useful predictive information for clinical treatment. The method we adopted has great development prospects as a way to predict the efficacy of new drugs and their main mechanisms of action, and it has a positive impact on the research and development of new drugs using drug repositioning and the modernization of traditional Chinese medicine.


Assuntos
Biologia Computacional , Reposicionamento de Medicamentos , Medicamentos de Ervas Chinesas , Simulação de Acoplamento Molecular , Comprimidos , Reposicionamento de Medicamentos/métodos , Humanos , Biologia Computacional/métodos , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/química , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Simulação de Dinâmica Molecular , Neoplasias Pulmonares/tratamento farmacológico , Farmacologia em Rede , Linhagem Celular Tumoral
6.
BMC Biol ; 22(1): 226, 2024 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-39379930

RESUMO

Drug repurposing is a promising approach in the field of drug discovery owing to its efficiency and cost-effectiveness. Most current drug repurposing models rely on specific datasets for training, which limits their predictive accuracy and scope. The number of both market-approved and experimental drugs is vast, forming an extensive molecular space. Due to limitations in parameter size and data volume, traditional drug-target interaction (DTI) prediction models struggle to generalize well within such a broad space. In contrast, large language models (LLMs), with their vast parameter sizes and extensive training data, demonstrate certain advantages in drug repurposing tasks. In our research, we introduce a novel drug repurposing framework, DrugReAlign, based on LLMs and multi-source prompt techniques, designed to fully exploit the potential of existing drugs efficiently. Leveraging LLMs, the DrugReAlign framework acquires general knowledge about targets and drugs from extensive human knowledge bases, overcoming the data availability limitations of traditional approaches. Furthermore, we collected target summaries and target-drug space interaction data from databases as multi-source prompts, substantially improving LLM performance in drug repurposing. We validated the efficiency and reliability of the proposed framework through molecular docking and DTI datasets. Significantly, our findings suggest a direct correlation between the accuracy of LLMs' target analysis and the quality of prediction outcomes. These findings signify that the proposed framework holds the promise of inaugurating a new paradigm in drug repurposing.


Assuntos
Reposicionamento de Medicamentos , Reposicionamento de Medicamentos/métodos , Humanos , Biologia Computacional/métodos , Descoberta de Drogas/métodos
7.
Indian J Otolaryngol Head Neck Surg ; 76(5): 3854-3859, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39376456

RESUMO

Benign paroxysmal positional vertigo (BPPV) is a common vestibular disorder characterized by brief episodes of vertigo triggered by changes in head position. Epley's manoeuvre and Semont's manoeuvre are widely used canalith repositioning procedures for the treatment of BPPV. This study aimed to compare the effectiveness of these two manoeuvres in treating post-canal BPPV in a cohort of 100 patients. METHODS: This was a prospective, comparative study conducted at a tertiary care hospital. One hundred patients diagnosed with post-canal BPPV were randomized into two groups: Group A (n = 50) underwent the Epley's manoeuvre, and Group B (n = 50) underwent the Semont's manoeuvre. The patients were assessed for the resolution of vertigo and nystagmus immediately after the manoeuvre and at a follow-up visit one week later. The resolution of symptoms was confirmed through Dix-Hallpike test. RESULTS: In Group A, 46 patients (92%) reported complete resolution of vertigo immediately after Epley's manoeuvre, and 47 patients (94%) had no nystagmus on the Dix-Hallpike test at the one-week follow-up. In Group B, 42 patients (84%) reported complete resolution of vertigo immediately after Semont's manoeuvre, and 44 patients (88%) had no nystagmus on the DH test at the one-week follow-up. The difference in effectiveness between the two manoeuvres was not statistically significant (p > 0.05). CONCLUSION: Both Epley's manoeuvre and Semont's manoeuvre are effective in treating post-canal BPPV, with similar success rates. The choice of manoeuvre may depend on patient preference, clinician expertise, and other individual factors. Further studies with larger sample sizes are warranted to validate these findings and explore other potential factors influencing the outcomes of canalith repositioning manoeuvres in BPPV.

8.
PNAS Nexus ; 3(10): pgae422, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39372540

RESUMO

Greenhouse gas emissions from the food system constitute about one-third of the global total, hence mitigation in this sphere of human activity is a vital goal for research and policy. This study empirically tests the effectiveness of different interventions to reduce the carbon footprint of food choices made on food-delivery apps, using an incentive-compatible online randomized controlled trial with 4,008 participants. The experiment utilized an interactive web platform that mimics popular online food-delivery platforms (such as Just Eat) and included three treatment conditions: a sign-posted meat tax, a carbon-footprint label, and a choice-architecture intervention that changed the order of the menu so that the lowest carbon-impact restaurants and dishes were presented first. Results show that only the choice-architecture nudge significantly reduced the average meal carbon footprint-by 0.3 kg/CO2e per order (12%), driven by a 5.6 percentage point (13%) reduction in high-carbon meal choices. Moreover, we find evidence of significant health and well-being co-benefits. Menu repositioning resulted in the average meal order having greater nutritional value and fewer calories, whilst significantly increasing self-reported satisfaction with the meal choice. Simple back-of-the-envelope calculations suggest that menu repositioning would be a highly cost-effective policy instrument if implemented at scale, with the return on investment expected to be in the range of £1.28 to £3.85 per metric ton of avoided CO2 emissions, depending on implementation costs.

9.
FASEB J ; 38(19): e70083, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-39373982

RESUMO

Drug-target binding affinity (DTA) prediction is vital for drug repositioning. The accuracy and generalizability of DTA models remain a major challenge. Here, we develop a model composed of BERT-Trans Block, Multi-Trans Block, and DTI Learning modules, referred to as Molecular Representation Encoder-based DTA prediction (MREDTA). MREDTA has three advantages: (1) extraction of both local and global molecular features simultaneously through skip connections; (2) improved sensitivity to molecular structures through the Multi-Trans Block; (3) enhanced generalizability through the introduction of BERT. Compared with 12 advanced models, benchmark testing of KIBA and Davis datasets demonstrated optimal performance of MREDTA. In case study, we applied MREDTA to 2034 FDA-approved drugs for treating non-small-cell lung cancer (NSCLC), all of which act on mutant EGFRT790M protein. The corresponding molecular docking results demonstrated the robustness of MREDTA.


Assuntos
Simulação de Acoplamento Molecular , Humanos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Reposicionamento de Medicamentos/métodos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/genética , Receptores ErbB/metabolismo , Receptores ErbB/química , Receptores ErbB/genética , Ligação Proteica , Antineoplásicos/farmacologia , Antineoplásicos/química
10.
Molecules ; 29(18)2024 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-39339469

RESUMO

Drug innovation traditionally follows a de novo approach with new molecules through a complex preclinical and clinical pathway. In addition to this strategy, drug repositioning has also become an important complementary approach, which can be shorter, cheaper, and less risky. This review provides an overview of drug innovation in both human and veterinary medicine, with a focus on drug repositioning. The evolution of drug repositioning and the effectiveness of this approach are presented, including the growing role of data science and computational modeling methods in identifying drugs with potential for repositioning. Certain business aspects of drug innovation, especially the relevant factors of market exclusivity, are also discussed. Despite the promising potential of drug repositioning for innovation, it remains underutilized, especially in veterinary applications. To change this landscape for mutual benefits of human and veterinary drug innovation, further exploitation of the potency of drug repositioning is necessary through closer cooperation between all stakeholders, academia, industry, pharmaceutical authorities, and innovation policy makers, and the integration of human and veterinary repositioning into a unified innovation space. For this purpose, the establishment of the conceptually new "One Health Drug Repositioning Platform" is proposed. Oncology is one of the disease areas where this platform can significantly support the development of new drugs for human and dog (or other companion animals) anticancer therapies. As an example of the utilization of human and veterinary drugs for veterinary repositioning, the use of COX inhibitors to treat dog cancers is reviewed.


Assuntos
Reposicionamento de Medicamentos , Drogas Veterinárias , Reposicionamento de Medicamentos/métodos , Humanos , Animais , Drogas Veterinárias/uso terapêutico , Neoplasias/tratamento farmacológico , Cães , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Antineoplásicos/química
11.
Int J Mol Sci ; 25(17)2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-39273420

RESUMO

Radiation therapy continues to be the cornerstone treatment for malignant brain tumors, the majority of which express wild-type p53. Therefore, the identification of drugs that promote the ionizing radiation (IR)-induced activation of p53 is expected to increase the efficacy of radiation therapy for these tumors. The growth inhibitory effects of CEP-1347, a known inhibitor of MDM4 expression, on malignant brain tumor cell lines expressing wild-type p53 were examined, alone or in combination with IR, by dye exclusion and/or colony formation assays. The effects of CEP-1347 on the p53 pathway, alone or in combination with IR, were examined by RT-PCR and Western blot analyses. The combination of CEP-1347 and IR activated p53 in malignant brain tumor cells and inhibited their growth more effectively than either alone. Mechanistically, CEP-1347 and IR each reduced MDM4 expression, while their combination did not result in further decreases. CEP-1347 promoted IR-induced Chk2 phosphorylation and increased p53 expression in concert with IR in a Chk2-dependent manner. The present results show, for the first time, that CEP-1347 is capable of promoting Chk2-mediated p53 activation by IR in addition to inhibiting the expression of MDM4 and, thus, CEP-1347 has potential as a radiosensitizer for malignant brain tumors expressing wild-type p53.


Assuntos
Neoplasias Encefálicas , Quinase do Ponto de Checagem 2 , Radiação Ionizante , Proteína Supressora de Tumor p53 , Humanos , Proteína Supressora de Tumor p53/metabolismo , Proteína Supressora de Tumor p53/genética , Quinase do Ponto de Checagem 2/metabolismo , Quinase do Ponto de Checagem 2/genética , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Proteínas de Ciclo Celular/metabolismo , Proteínas de Ciclo Celular/genética , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas/genética , Fosforilação/efeitos dos fármacos , Proteínas Nucleares/metabolismo , Proteínas Nucleares/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos da radiação
12.
Molecules ; 29(17)2024 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-39274873

RESUMO

A 3D structure-based pharmacophore model built for bromodomain-containing protein 4 (BRD4) is reported here, specifically developed for investigating and identifying the key structural features of the (+)-JQ1 known inhibitor within the BRD4 binding site. Using this pharmacophore model, 273 synthesized and purchased compounds previously considered for other targets but yielding poor results were screened in a drug repositioning campaign. Subsequently, only six compounds showed potential as BRD4 binders and were subjected to further biophysical and biochemical assays. Compounds 2, 5, and 6 showed high affinity for BRD4, with IC50 values of 0.60 ± 0.25 µM, 3.46 ± 1.22 µM, and 4.66 ± 0.52 µM, respectively. Additionally, these compounds were tested against two other bromodomains, BRD3 and BRD9, and two of them showed high selectivity for BRD4. The reported 3D structure-based pharmacophore model proves to be a straightforward and useful tool for selecting novel BRD4 ligands.


Assuntos
Proteínas de Ciclo Celular , Fatores de Transcrição , Fatores de Transcrição/antagonistas & inibidores , Fatores de Transcrição/metabolismo , Fatores de Transcrição/química , Proteínas de Ciclo Celular/antagonistas & inibidores , Proteínas de Ciclo Celular/metabolismo , Proteínas de Ciclo Celular/química , Humanos , Ligação Proteica , Ligantes , Reposicionamento de Medicamentos , Sítios de Ligação , Proteínas Nucleares/antagonistas & inibidores , Proteínas Nucleares/metabolismo , Proteínas Nucleares/química , Triazóis/química , Triazóis/farmacologia , Azepinas/química , Azepinas/farmacologia , Simulação de Acoplamento Molecular , Modelos Moleculares , Relação Estrutura-Atividade , Avaliação Pré-Clínica de Medicamentos , Farmacóforo , Proteínas que Contêm Bromodomínio
13.
Sci Rep ; 14(1): 22695, 2024 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-39349563

RESUMO

Epilepsy, frequently comorbid with anxiety, is a prevalent neurological disorder. Available drugs often have side effects that hinder adherence, creating a need for new treatments. Potassium channel activators have emerged as promising candidates for treating both epilepsy and anxiety. This study aimed to evaluate the potential anticonvulsant and anxiolytic effects of pinacidil, an ATP-sensitive potassium channel activator used as antihypertensive, in rats. Our results indicate that pinacidil at 10 mg/kg (i.p.) fully protected animals from seizures induced by pentylenetetrazol (PTZ) and provided 85.7%, 100% and 100% protection against pilocarpine-induced seizures at 2.5, 5 and 10 mg/kg (i.p.), respectively. Although the 2.5 and 5 mg/kg (i.p) doses did not significantly protect the animals from PTZ-induced seizures, they did significantly increase the latency to the first seizure. Pinacidil also demonstrated mild anxiolytic activity, particularly at 10 mg/kg (i.p), evidenced by increased time spent in the open or illuminated areas of the Elevated Plus Maze (EPM) and Light-Dark Box (LDB) and increased exploratory activity in the Open Filed, EPM and LDB. Pinacidil did not affect locomotor performance, supporting its genuine anticonvulsant effects. This study holds significant medical and pharmaceutical value by characterizing pinacidil's anticonvulsant and anxiolytic effects and highlighting its potential for therapeutic repositioning.


Assuntos
Ansiolíticos , Anticonvulsivantes , Modelos Animais de Doenças , Pentilenotetrazol , Pinacidil , Convulsões , Animais , Anticonvulsivantes/farmacologia , Anticonvulsivantes/uso terapêutico , Ansiolíticos/farmacologia , Ansiolíticos/uso terapêutico , Masculino , Convulsões/tratamento farmacológico , Convulsões/induzido quimicamente , Camundongos , Ratos , Pinacidil/farmacologia , Reposicionamento de Medicamentos , Ansiedade/tratamento farmacológico , Pilocarpina , Comportamento Animal/efeitos dos fármacos , Ratos Wistar
14.
J Alzheimers Dis ; 101(4): 1355-1366, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39269834

RESUMO

Background: Alzheimer's disease (AD) is a neurodegenerative disorder that is the most common form of dementia in the elderly. The drugs currently used to treat AD only have limited effects and are not able to cure the disease. Drug repositioning has increasingly become a promising approach to find potential drugs for diseases like AD. Objective: To screen potential drug candidates for AD based on the relationship between risk genes of AD and drugs. Methods: We collected the risk genes of AD and retrieved the information of known drugs from DrugBank. Then, the AD-related genes and the targets of each drug were mapped to the human protein-protein interaction network (PPIN) to represent AD and the drugs on the network. The network distances between each drug and AD were calculated to screen the drugs proximal to AD-related genes on PPIN, and the screened drug candidates were further analyzed by molecular docking and molecular dynamics simulations. Results: We compiled a list of 714 genes associated with AD. From 5,833 drugs used for human diseases, we identified 1,044 drugs that could be potentially used to treat AD. Then, amyloid-ß (Aß) protein, the key molecule involved in the pathogenesis of AD was selected as the target to further screen drugs that may inhibit Aß aggregation by molecular docking. We found that ergotamine and RAF-265 could bind stably with Aß. In further analysis by molecular dynamics simulations, both drugs exhibited reasonable stability. Conclusions: Our work indicated that ergotamine and RAF-265 may be potential candidates for treating AD.


Assuntos
Doença de Alzheimer , Reposicionamento de Medicamentos , Ergotamina , Simulação de Acoplamento Molecular , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/genética , Reposicionamento de Medicamentos/métodos , Humanos , Ergotamina/uso terapêutico , Mapas de Interação de Proteínas/efeitos dos fármacos , Peptídeos beta-Amiloides/metabolismo , Simulação de Dinâmica Molecular
15.
Biochem J ; 481(20): 1379-1393, 2024 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-39312210

RESUMO

The pursuit of novel therapeutics is a complex and resource-intensive endeavor marked by significant challenges, including high costs and low success rates. In response, drug repositioning strategies leverage existing FDA-approved compounds to predict their efficacy across diverse diseases. Peptidyl arginine deiminase 4 (PAD4) plays a pivotal role in protein citrullination, a process implicated in the autoimmune pathogenesis of rheumatoid arthritis (RA). Targeting PAD4 has thus emerged as a promising therapeutic approach. This study employs computational and enzyme inhibition strategies to identify potential PAD4-targeting compounds from a library of FDA-approved drugs. In silico docking analyses validated the binding interactions and orientations of screened compounds within PAD4's active site, with key residues such as ASP350, HIS471, ASP473, and CYS645 participating in crucial hydrogen bonding and van der Waals interactions. Molecular dynamics simulations further assessed the stability of top compounds exhibiting high binding affinities. Among these compounds, Saquinavir (SQV) emerged as a potent PAD4 inhibitor, demonstrating competitive inhibition with a low IC50 value of 1.21 ± 0.04 µM. In vitro assays, including enzyme kinetics and biophysical analyses, highlighted significant changes in PAD4 conformation upon SQV binding, as confirmed by circular dichroism spectroscopy. SQV induced localized alterations in PAD4 structure, effectively occupying the catalytic pocket and inhibiting enzymatic activity. These findings underscore SQV's potential as a therapeutic candidate for RA through PAD4 inhibition. Further validation through in vitro and in vivo studies is essential to confirm SQV's therapeutic benefits in autoimmune diseases associated with dysregulated citrullination.


Assuntos
Artrite Reumatoide , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Proteína-Arginina Desiminase do Tipo 4 , Saquinavir , Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/enzimologia , Proteína-Arginina Desiminase do Tipo 4/antagonistas & inibidores , Proteína-Arginina Desiminase do Tipo 4/metabolismo , Proteína-Arginina Desiminase do Tipo 4/química , Humanos , Saquinavir/química , Saquinavir/farmacologia , Reposicionamento de Medicamentos , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/uso terapêutico , Desiminases de Arginina em Proteínas/antagonistas & inibidores , Desiminases de Arginina em Proteínas/metabolismo , Desiminases de Arginina em Proteínas/química , Domínio Catalítico , Hidrolases/antagonistas & inibidores , Hidrolases/química , Hidrolases/metabolismo
16.
Front Pharmacol ; 15: 1455696, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39346565

RESUMO

Many bacteria act pathogenic by the release of AB-type protein toxins that efficiently enter human or animal cells and act as enzymes in their cytosol. This leads to disturbed cell functions and the clinical symptoms characteristic for the individual toxin. Therefore, molecules that directly target and neutralize these toxins provide promising novel therapeutic options. Here, we found that the FDA-approved drug disulfiram (DSF), used for decades to treat alcohol abuse, protects cells from intoxication with diphtheria toxin (DT) from Corynebacterium diphtheria, the causative agent of diphtheria, lethal toxin (LT) from Bacillus anthracis, which contributes to anthrax, and C2 enterotoxin from Clostridium botulinum when applied in concentrations lower than those found in plasma of patients receiving standard DSF treatment for alcoholism (up to 20 µM). Moreover, this inhibitory effect is increased by copper, a known enhancer of DSF activity. LT and C2 are binary toxins, consisting of two non-linked proteins, an enzyme (A) and a separate binding/transport (B) subunit. To act cytotoxic, their proteolytically activated B subunits PA63 and C2IIa, respectively, form barrel-shaped heptamers that bind to their cellular receptors and form complexes with their respective A subunits LF and C2I. The toxin complexes are internalized via receptor-mediated endocytosis and in acidified endosomes, PA63 and C2IIa form pores in endosomal membranes, which facilitate translocation of LF and C2I into the cytosol, where they act cytotoxic. In DT, A and B subunits are located within one protein, but DT also forms pores in endosomes that facilitate translocation of the A subunit. If cell binding, membrane translocation, or substrate modification is inhibited, cells are protected from intoxication. Our results implicate that DSF neither affects cellular binding nor the catalytic activity of the investigated toxins to a relevant extend, but interferes with the toxin pore-mediated translocation of the A subunits of DT, LT and C2 toxin, as demonstrated by membrane-translocation assays and toxin pore conductivity experiments in the presence or absence of DSF. Since toxin translocation across intracellular membranes represents a central step during cellular uptake of many bacterial toxins, DSF might neutralize a broad spectrum of medically relevant toxins.

17.
J Funct Morphol Kinesiol ; 9(3)2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-39311261

RESUMO

We investigated the acute biophysical responses of changing the mandibular position during a rowing incremental protocol. A World-class 37-year-old male rower performed two 7 × 3 min ergometer rowing trials, once with no intraoral splint (control) and the other with a mandibular forward repositioning splint (splint condition). Ventilatory, kinematics and body electromyography were evaluated and compared between trials (paired samples t-test, p ≤ 0.05). Under the splint condition, oxygen uptake was lower, particularly at higher exercise intensities (67.3 ± 2.3 vs. 70.9 ± 1.5 mL·kg-1·min-1), and ventilation increased during specific rowing protocol steps (1st-4th and 6th). Wearing the splint condition led to changes in rowing technique, including a slower rowing frequency ([18-30] vs. [19-32] cycles·min-1) and a longer propulsive movement ([1.58-1.52] vs. [1.56-1.50] m) than the control condition. The splint condition also had a faster propulsive phase and a prolonged recovery period than the control condition. The splint reduced peak and mean upper body muscle activation, contrasting with an increase in lower body muscle activity, and generated an energetic benefit by reducing exercise cost and increasing rowing economy compared to the control condition. Changing the mandibular position benefited a World-class rower, supporting the potential of wearing an intraoral splint in high-level sports, particularly in rowing.

18.
Anticancer Res ; 44(10): 4301-4307, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39348966

RESUMO

BACKGROUND/AIM: Ovarian cancer (OC) is a leading cause of cancer-related mortality among women, and there remains a significant unmet need for new therapeutic agents to improve patient outcomes. This study aimed to explore drug repositioning by screening a library of Food and Drug Administration (FDA)-approved compounds to identify those with therapeutic potential against OC. We also aimed to elucidate the molecular mechanisms of action of such compounds to better understand how they inhibit cancer cell proliferation. MATERIALS AND METHODS: Using the WST-1 assay, a library of 1710 FDA-approved drugs was screened to evaluate their effects on OC cell proliferation. The molecular mechanisms underlying the effects of selected compounds were assessed through terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay and immunoblot analysis. RESULTS: Screening of FDA-approved libraries revealed valrubicin as a potent inhibitor of OVCAR8 cell proliferation and SKOV3 and A2780 cell growth. Furthermore, valrubicin treatment led to increased DNA fragmentation, as evidenced by the TUNEL assay, and activated apoptosis signaling through enhancement of cleaved caspase-3 and poly(ADP-ribose) polymerase levels. CONCLUSION: Valrubicin, through drug repositioning, can be applied as a new therapeutic agent for OC.


Assuntos
Apoptose , Proliferação de Células , Reposicionamento de Medicamentos , Neoplasias Ovarianas , Humanos , Feminino , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/patologia , Proliferação de Células/efeitos dos fármacos , Linhagem Celular Tumoral , Apoptose/efeitos dos fármacos , Antineoplásicos/farmacologia
19.
Antibiotics (Basel) ; 13(9)2024 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-39335008

RESUMO

Intracellular bacterial pathogens pose significant public health challenges due to their ability to evade immune defenses and conventional antibiotics. Drug repurposing has recently been explored as a strategy to discover new therapeutic uses for established drugs to combat these infections. Utilizing high-throughput screening, bioinformatics, and systems biology, several existing drugs have been identified with potential efficacy against intracellular bacteria. For instance, neuroleptic agents like thioridazine and antipsychotic drugs such as chlorpromazine have shown effectiveness against Staphylococcus aureus and Listeria monocytogenes. Furthermore, anticancer drugs including tamoxifen and imatinib have been repurposed to induce autophagy and inhibit bacterial growth within host cells. Statins and anti-inflammatory drugs have also demonstrated the ability to enhance host immune responses against Mycobacterium tuberculosis. The review highlights the complex mechanisms these pathogens use to resist conventional treatments, showcases successful examples of drug repurposing, and discusses the methodologies used to identify and validate these drugs. Overall, drug repurposing offers a promising approach for developing new treatments for bacterial infections, addressing the urgent need for effective antimicrobial therapies.

20.
Int J Mol Sci ; 25(18)2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-39337269

RESUMO

Previously, we have demonstrated that amiodarone (AM), a widely used antiarrhythmic drug, and its major metabolite desethylamiodarone (DEA) both affect several mitochondrial processes in isolated heart and liver mitochondria. Also, we have established DEA's antitumor properties in various cancer cell lines and in a rodent metastasis model. In the present study, we compared AM's and DEA's mitochondrial and antineoplastic effects in a human triple-negative breast cancer (TNBC) cell line. Both compounds reduced viability in monolayer and sphere cultures and the invasive growth of the MDA-MB-231 TNBC line by inducing apoptosis. They lowered mitochondrial trans-membrane potential, increased Ca2+ influx, induced mitochondrial permeability transition, and promoted mitochondrial fragmentation. In accordance with their mitochondrial effects, both substances massively decreased overall, and even to a greater extent, mitochondrial ATP production decreased, as determined using a Seahorse live cell respirometer. In all these effects, DEA was more effective than AM, indicating that DEA may have higher potential in the therapy of TNBC than its parent compound.


Assuntos
Amiodarona , Antineoplásicos , Apoptose , Mitocôndrias , Neoplasias de Mama Triplo Negativas , Amiodarona/farmacologia , Amiodarona/análogos & derivados , Humanos , Mitocôndrias/metabolismo , Mitocôndrias/efeitos dos fármacos , Linhagem Celular Tumoral , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/metabolismo , Neoplasias de Mama Triplo Negativas/patologia , Feminino , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Trifosfato de Adenosina/metabolismo , Cálcio/metabolismo , Proliferação de Células/efeitos dos fármacos
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