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1.
Future Microbiol ; 19(16): 1365-1375, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39235062

RESUMO

Aim: To evaluate the antifungal activity of amlodipine against strains of Candida spp. and to its possible mechanism of action.Methods: Broth microdilution tests were used to determine the minimum inhibitory concentration, while the synergistic activity was evaluated by calculating the fractional inhibitory concentration index. The action of amlodipine against biofilms was determined using the MTT assay and its possible mechanism of action was investigated through flow cytometry tests.Results: Amlodipine showed MICs ranging from 62.5 to 250 µg/ml, in addition to action against pre-formed and forming biofilms, with reductions between 50 and 90%. Amlodipine increases the externalization of phosphatidylserine and reduces the cell viability of fungal cells, suggesting apoptosis.Conclusion: Amlodipine had good antifungal activity against planktonic cells and biofilms of Candida spp., by leading the cells to apoptosis.


Candida is a type of fungus that can cause diseases. This fungus became stronger over time and drugs can no longer kill them easily, so it is important to find new drugs. We decided to study whether amlodipine, a drug used for heart disease, has action against Candida. We discovered that amlodipine make fungi weaker. We still need to do more studies to find out if amlodipine can help prevent Candida diseases.


Assuntos
Anlodipino , Antifúngicos , Biofilmes , Candida , Testes de Sensibilidade Microbiana , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Antifúngicos/farmacologia , Candida/efeitos dos fármacos , Candida/fisiologia , Candida/crescimento & desenvolvimento , Anlodipino/farmacologia , Viabilidade Microbiana/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Humanos , Citometria de Fluxo , Plâncton/efeitos dos fármacos , Plâncton/crescimento & desenvolvimento
2.
Braz J Microbiol ; 2024 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-39297913

RESUMO

OBJECTIVES: This study addressed the need for new treatments for severe Candida infections, especially resistant strains. It evaluated the antifungal potential of geraniol alone and with fluconazole against various Candida spp., including resistant strains, and investigated geraniol's mechanism of action using flow cytometry. METHODS: The research assessed the inhibitory effects of geraniol on the growth of various Candida species at concentrations ranging from 110 to 883 µg/ml. The study also explored the potential synergistic effects when geraniol was combined with fluconazole. The mechanism of action was investigated through flow cytometry, with a particular emphasis on key enzymes associated with plasma membrane synthesis, membrane permeability changes, mitochondrial membrane depolarization, reactive oxygen species (ROS) induction, and genotoxicity. RESULTS: Geraniol demonstrated significant antifungal activity against different Candida species, inhibiting growth at concentrations within the range of 110 to 883 µg/ml. The mechanism of action appeared to be multifactorial. Geraniol was associated with the inhibition of crucial enzymes involved in plasma membrane synthesis, increased membrane permeability, induction of mitochondrial membrane depolarization, elevated ROS levels, and the presence of genotoxicity. These effects collectively contributed to cell apoptosis. CONCLUSIONS: Geraniol, alone and in combination with fluconazole, shows promise as a potential therapeutic option for Candida spp. INFECTIONS: Its diverse mechanism of action, impacting crucial cellular processes, highlights its potential as an effective antifungal agent. Further research into geraniol's therapeutic applications may aid in developing innovative strategies to address Candida infections, especially those resistant to current therapies.

3.
J Clin Invest ; 134(18)2024 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-39286979

RESUMO

The widespread use of potent androgen receptor signaling inhibitors (ARSIs) has led to an increasing emergence of AR-independent castration-resistant prostate cancer (CRPC), typically driven by loss of AR expression, lineage plasticity, and transformation to prostate cancers (PCs) that exhibit phenotypes of neuroendocrine or basal-like cells. The anti-apoptotic protein BCL2 is upregulated in neuroendocrine cancers and may be a therapeutic target for this aggressive PC disease subset. There is an unmet clinical need, therefore, to clinically characterize BCL2 expression in metastatic CRPC (mCRPC), determine its association with AR expression, uncover its mechanisms of regulation, and evaluate BCL2 as a therapeutic target and/or biomarker with clinical utility. Here, using multiple PC biopsy cohorts and models, we demonstrate that BCL2 expression is enriched in AR-negative mCRPC, associating with shorter overall survival and resistance to ARSIs. Moreover, high BCL2 expression associates with lineage plasticity features and neuroendocrine marker positivity. We provide evidence that BCL2 expression is regulated by DNA methylation, associated with epithelial-mesenchymal transition, and increased by the neuronal transcription factor ASCL1. Finally, BCL2 inhibition had antitumor activity in some, but not all, BCL2-positive PC models, highlighting the need for combination strategies to enhance tumor cell apoptosis and enrich response.


Assuntos
Regulação Neoplásica da Expressão Gênica , Neoplasias de Próstata Resistentes à Castração , Proteínas Proto-Oncogênicas c-bcl-2 , Masculino , Humanos , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Neoplasias de Próstata Resistentes à Castração/genética , Neoplasias de Próstata Resistentes à Castração/patologia , Neoplasias de Próstata Resistentes à Castração/metabolismo , Animais , Linhagem Celular Tumoral , Receptores Androgênicos/metabolismo , Receptores Androgênicos/genética , Camundongos , Metilação de DNA , Transição Epitelial-Mesenquimal , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Linhagem da Célula , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Proteínas de Neoplasias/biossíntese
4.
Future Microbiol ; 19(15): 1309-1320, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39101446

RESUMO

Aim: Evaluate the anticandidal effect of Croton heliotropiifolius Kunth essential oil and its interaction with azoles and N-acetylcysteine (NAC) against planktonic cells and biofilms.Materials & methods: Broth microdilution and checkerboard methods were used to evaluate the individual and combined activity with fluconazole and itraconazole (ITRA). The antibiofilm effect of the oil was assessed in 96-well plates alone and combined with ITRA and NAC, and cytotoxicity determined by MTT.Results: The oil inhibited all Candida species growth. The activity was enhanced when associated with ITRA and NAC for planktonic cells and biofilms in formation. The effective concentrations were lower than the toxic ones to V79 cells.Conclusion: C. heliotropiifolius Kunth essential oil is an anticandidal alternative, and can be associated with ITRA and NAC.


Candida is a type of fungus that can cause disease in people. In recent years, the number of available drugs to treat this disease have declined. It is important to search for new drugs. Plants are often used to improve health, so we tested the essential oil of a plant called Croton heliotropiifolius to see if it could kill the fungus. We found that the essential oil could kill the fungus, and could be used with other drugs to improve their effects.


Assuntos
Acetilcisteína , Antifúngicos , Biofilmes , Candida , Croton , Itraconazol , Testes de Sensibilidade Microbiana , Óleos Voláteis , Croton/química , Óleos Voláteis/farmacologia , Óleos Voláteis/química , Itraconazol/farmacologia , Antifúngicos/farmacologia , Acetilcisteína/farmacologia , Biofilmes/efeitos dos fármacos , Candida/efeitos dos fármacos , Sinergismo Farmacológico , Animais , Linhagem Celular , Fluconazol/farmacologia , Cricetinae
5.
Vet Parasitol ; 331: 110281, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39111197

RESUMO

Rhipicephalus microplus is among the most important ectoparasites for livestock. The use of synthetic acaricides has raised some concerns due to the selection of tick populations that are resistant to acaricides and environmental contamination. Therefore, plant extracts have been used as alternatives for the treatment of animals infested with ticks. In this study, R. microplus populations from seven different dairy farms were collected and assessed for their resistance to the acaricides cypermethrin or trichlorfon. Larvae of the most resistant population were used in assays to evaluate the acaricide effect of leaf extracts from plants of the Brazilian savanna. The most active extracts were also tested against fully engorged females. Among seven tick populations, five and three showed resistance level ≥ III for cypermethrin or trichlorfon, respectively. The most resistant tick population was evaluated in mortality assays with the plants Piptadenia viridiflora, Annona crassiflora, Caryocar brasiliense, Ximenia americana, and Schinopsis brasilienses. The ethanolic extracts of C. brasiliense, X. americana and S. brasilienses showed higher larvicidal effects in comparison to the other extracts and cypermethrin. The ethanolic extract of X. americana showed 60.79 % efficacy against fully engorged females of the acaricide resistant tick strain. The ethanolic extracts of C. brasiliense, X. americana, and S. brasilienses showed peaks in HPLC-DAD, indicating the presence of tannins and flavonoids. Three of the plants showed promising results and should be explored in further studies to develop novel tools to control R. microplus in cattle.


Assuntos
Acaricidas , Extratos Vegetais , Piretrinas , Rhipicephalus , Triclorfon , Animais , Rhipicephalus/efeitos dos fármacos , Piretrinas/farmacologia , Acaricidas/farmacologia , Brasil , Feminino , Extratos Vegetais/farmacologia , Triclorfon/farmacologia , Larva/efeitos dos fármacos , Pradaria , Bovinos , Resistência a Medicamentos , Folhas de Planta/química , Doenças dos Bovinos/parasitologia , Doenças dos Bovinos/tratamento farmacológico
6.
Braz J Microbiol ; 2024 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-39179891

RESUMO

The increase in fungal resistance is a major public health concern. In this context, Candida spp. is an important genus related to invasive diseases, especially in immunosuppressed patients. The relevance of alternative approaches to increasing fungal resistance stands out, in which products of natural origin demonstrate potential antifungal activity in vitro against Candida spp. In this sense, this work aimed to evaluate the in vitro activity of tannic acid against Candida spp. Minimum inhibitory concentration (MIC) was determined for tannic acid and the antifungals, and the checkerboard assay was performed to analyze the interactions between them. Furthermore, we evaluated the tannic acid antibiofilm activity and its possible mechanism of action. Tannic acid showed MIC ranging to 0.06 to 0.5 µg/ml and showed no loss of effectiveness when combined with antifungals. Also, is safe at the concentrations it exerts its antifungal activity in pre-formed biofilms, as demonstrated by IC50 in murine fibroblasts cells and the hemolytic assay. Additionally, its mechanisms of action can be related with induction of signals that lead to apoptosis in fungal cells.

7.
Clin Sci (Lond) ; 138(17): 1071-1087, 2024 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-39136472

RESUMO

Perivascular adipose tissue (PVAT) negatively regulates vascular muscle contraction. However, in the context of obesity, the PVAT releases vasoconstrictor substances that detrimentally affect vascular function. A pivotal player in this scenario is the peptide endothelin-1 (ET-1), which induces oxidative stress and disrupts vascular function. The present study postulates that obesity augments ET-1 production in the PVAT, decreases the function of the nuclear factor erythroid 2-related factor-2 (Nrf2) transcription factor, further increasing reactive oxygen species (ROS) generation, culminating in PVAT dysfunction. Male C57BL/6 mice were fed either a standard or a high-fat diet for 16 weeks. Mice were also treated with saline or a daily dose of 100 mg·kg-1 of the ETA and ETB receptor antagonist Bosentan, for 7 days. Vascular function was evaluated in thoracic aortic rings, with and without PVAT. Mechanistic studies utilized PVAT from all groups and cultured WT-1 mouse brown adipocytes. PVAT from obese mice exhibited increased ET-1 production, increased ECE1 and ETA gene expression, loss of the anticontractile effect, as well as increased ROS production, decreased Nrf2 activity, and downregulated expression of Nrf2-targeted antioxidant genes. PVAT of obese mice also exhibited increased expression of Tyr216-phosphorylated-GSK3ß and KEAP1, but not BACH1 - negative Nrf2 regulators. Bosentan treatment reversed all these effects. Similarly, ET-1 increased ROS generation and decreased Nrf2 activity in brown adipocytes, events mitigated by BQ123 (ETA receptor antagonist). These findings place ET-1 as a major contributor to PVAT dysfunction in obesity and highlight that pharmacological control of ET-1 effects restores PVAT's cardiovascular protective role.


Assuntos
Tecido Adiposo , Regulação para Baixo , Endotelina-1 , Camundongos Endogâmicos C57BL , Fator 2 Relacionado a NF-E2 , Obesidade , Espécies Reativas de Oxigênio , Animais , Endotelina-1/metabolismo , Obesidade/metabolismo , Obesidade/fisiopatologia , Masculino , Tecido Adiposo/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Bosentana/farmacologia , Dieta Hiperlipídica , Camundongos , Estresse Oxidativo , Receptor de Endotelina A/metabolismo , Receptor de Endotelina A/genética , Enzimas Conversoras de Endotelina/metabolismo , Aorta Torácica/metabolismo , Aorta Torácica/efeitos dos fármacos , Aorta Torácica/fisiopatologia
8.
Braz J Microbiol ; 2024 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-39198376

RESUMO

Candida species are among the priority pathogens in the area of research and development. Due to the problems associated with resistance to antifungals, new therapeutic alternatives are necessary. In this regard, drug repositioning has gained prominence. The objective of this study was to evaluate the activity of three tricyclic antidepressants (TCAs) - amitriptyline (AMT), nortriptyline (NOR) and clomipramine (CLO) - isolated or associated with antifungals against strains of Candida spp., as well as to analyze the possible mechanism of action. Among the methods used were broth microdilution tests, tolerance level assessment, checkerboard assays, flow cytometry and fluorescence microscopy. Furthermore, Candida cells were visualized after treatments by scanning electron microscopy (SEM). AMT presented MIC 50% in the range of 16 to 128 µg/mL, NOR from 8 to 128 µg/mL, and CLO from 8 to 64 µg/mL, with all three TCAs having a fungicidal inhibitory action profile. For these TCAs, there was synergism with amphotericin B (AMB) in 100% of the isolates. In association with fluconazole (FLC) and itraconazole (ITR), there were mostly indifferent interactions. TCAs isolated and associated with AMB reduced cell viability, promoted DNA fragmentation and damage, caused mitochondrial depolarization, externalization of phosphatidylserine, produced reactive oxygen species (ROS), decreased reduced glutathione (GSH) and increased carbonyl protein levels, causing morphological changes. The results suggest the antifungal mechanism of the TCAs works via the apoptotic pathway.

9.
Stud Health Technol Inform ; 316: 1024-1028, 2024 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-39176964

RESUMO

This study explores the integration of Large Language Models (LLMs) into nursing education, highlighting a paradigm shift towards interactive learning environments. We aimed to analyze the literature to identify how large language models are being implemented in nursing education, as well as key opportunities and limitations that need to be addressed. English records published since 2022 were retrieved from 4 databases including LLMs in nursing education. A total of 19 records were eligible. As LLMs advanced natural language processing capabilities enable interactive learning experiences, nursing educators are presented with unique opportunities to enhance curriculum delivery, foster critical thinking, and simulate complex clinical scenarios. Through a comprehensive analysis of current applications, limitations and future research, this paper navigates the complexities of adopting LLMs (eg ChatGPT) in nursing education. This paper concludes with a call for action to advance the integration of AI in nursing, enhancing educational outcomes while ensuring ethical, effective use.


Assuntos
Educação em Enfermagem , Aprendizado de Máquina , Processamento de Linguagem Natural , Humanos , Instrução por Computador/métodos , Currículo , Educação em Enfermagem/ética , Educação em Enfermagem/métodos , Aprendizado de Máquina/ética
10.
J Med Microbiol ; 73(7)2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38979984

RESUMO

Introduction. The development of new antifungal drugs has become a global priority, given the increasing cases of fungal diseases together with the rising resistance to available antifungal drugs. In this scenario, drug repositioning has emerged as an alternative for such development, with advantages such as reduced research time and costs.Gap statement. Propafenone is an antiarrhythmic drug whose antifungal activity is poorly described, being a good candidate for further study.Aim. This study aims to evaluate propafenone activity against different species of Candida spp. to evaluate its combination with standard antifungals, as well as its possible action mechanism.Methodology. To this end, we carried out tests against strains of Candida albicans, Candida auris, Candida parapsilosis, Candida tropicalis, Candida glabrata and Candida krusei based on the evaluation of the MIC, minimum fungicidal concentration and tolerance level, along with checkerboard and flow cytometry tests with clinical strains and cell structure analysis by scanning electron microscopy (SEM).Results. The results showed that propafenone has a 50% MIC ranging from 32 to 256 µg ml-1, with fungicidal activity and positive interactions with itraconazole in 83.3% of the strains evaluated. The effects of the treatments observed by SEM were extensive damage to the cell structure, while flow cytometry revealed the apoptotic potential of propafenone against Candida spp.Conclusion. Taken together, these results indicate that propafenone has the potential for repositioning as an antifungal drug.


Assuntos
Antifúngicos , Candida , Testes de Sensibilidade Microbiana , Propafenona , Antifúngicos/farmacologia , Candida/efeitos dos fármacos , Candida/crescimento & desenvolvimento , Propafenona/farmacologia , Humanos , Itraconazol/farmacologia , Sinergismo Farmacológico , Farmacorresistência Fúngica/efeitos dos fármacos , Candidíase/microbiologia , Candidíase/tratamento farmacológico , Reposicionamento de Medicamentos
11.
Microb Pathog ; 193: 106769, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38955237

RESUMO

The bacterium Escherichia coli is one of the main causes of urinary tract infections. The formation of bacterial biofilms, especially associated with the use of urinary catheters, contributes to the establishment of recurrent infections and the development of resistance to treatment. Strains of E. coli that produce extended-spectrum beta-lactamases (ESBL) have a greater ability to form biofilms. In addition, there is a lack of drugs available in the market with antibiofilm activity. Promethazine (PMZ) is an antihistamine known to have antimicrobial activity against different pathogens, including in the form of biofilms, but there are still few studies of its activity against ESBL E. coli biofilms. The aim of this study was to evaluate the antimicrobial activity of PMZ against ESBL E. coli biofilms, as well as to assess the application of this drug as a biofilm prevention agent in urinary catheters. To this end, the minimum inhibitory concentration and minimum bactericidal concentration of PMZ in ESBL E. coli strains were determined using the broth microdilution assay and tolerance level measurement. The activity of PMZ against the cell viability of the in vitro biofilm formation of ESBL E. coli was analyzed by the MTT colorimetric assay and its ability to prevent biofilm formation when impregnated in a urinary catheter was investigated by counting colony-forming units (CFU) and confirmed by scanning electron microscopy (SEM). PMZ showed bactericidal activity and significantly reduced (p < 0.05) the viability of the biofilm being formed by ESBL E. coli at concentrations of 256 and 512 µg/ml, as well as preventing the formation of biofilm on urinary catheters at concentrations starting at 512 µg/ml by reducing the number of CFUs, as also observed by SEM. Thus, PMZ is a promising candidate to prevent the formation of ESBL E. coli biofilms on abiotic surfaces.


Assuntos
Antibacterianos , Biofilmes , Escherichia coli , Testes de Sensibilidade Microbiana , Prometazina , Cateteres Urinários , beta-Lactamases , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Prometazina/farmacologia , Escherichia coli/efeitos dos fármacos , beta-Lactamases/metabolismo , Cateteres Urinários/microbiologia , Antibacterianos/farmacologia , Humanos , Infecções Urinárias/microbiologia , Viabilidade Microbiana/efeitos dos fármacos , Infecções por Escherichia coli/microbiologia , Infecções por Escherichia coli/tratamento farmacológico
12.
Future Microbiol ; 19(13): 1157-1170, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39012219

RESUMO

Aim: To evaluate the antifungal activity of mangiferin against Candida spp. resistant to fluconazole.Materials & methods: The antifungal activity of mangiferin was assessed using broth microdilution and its interaction with azoles and amphotericin B was evaluated by checkerboard. The activity of mangiferin against Candida spp. biofilms was assessed using the MTT colorimetric assay and its possible mechanism of action was evaluated using flow cytometry.Results: Mangiferin showed activity against Candida albicans, Candida tropicalis and Candida parapsilosis resistant to fluconazole and showed synergism with azoles and amphotericin B. Mangiferin increased the activity of antifungals against Candida biofilms and caused depolarization of the mitochondrial membrane and externalization of phosphatidylserine, suggesting apoptosis.Conclusion: mangiferin combined with antifungals has potential against Candida spp.


Candida is a type of fungus that can make people ill. Over time, many species of Candida have found ways to resist the drugs used to kill them. It is important to find new drugs. We decided to see if a substance called mangiferin works against Candida. We found that mangiferin works against Candida and may help other drugs to work better. We still need to do more studies to find out whether mangiferin can help prevent diseases caused by Candida in the future.


Assuntos
Anfotericina B , Antifúngicos , Biofilmes , Candida , Farmacorresistência Fúngica , Sinergismo Farmacológico , Fluconazol , Testes de Sensibilidade Microbiana , Xantonas , Antifúngicos/farmacologia , Xantonas/farmacologia , Fluconazol/farmacologia , Biofilmes/efeitos dos fármacos , Farmacorresistência Fúngica/efeitos dos fármacos , Anfotericina B/farmacologia , Candida/efeitos dos fármacos , Humanos , Apoptose/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Azóis/farmacologia
13.
Sci Total Environ ; 948: 174586, 2024 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-38997014

RESUMO

Per- and polyfluoroalkyl substances (PFAS) comprise >4000 synthetic substances used in industrial applications and consumer products. PFAS used daily in households and manufacturing plants end up in domestic sewage, and industrial effluents can be discharged to surface water. Urban watersheds located in low and middle-income countries (LMIC), which lack sanitation infrastructure, are potential recipients of waste containing PFAS. Yet, only a few studies report PFAS occurrence in urban reservoirs and lakes, especially those located in the Global South due to resource limitations. This is the first study aimed to assess PFAS occurrence and ecological risks in Pampulha Lake, Brazil, a site which represents the reality of many other urban watersheds in LMIC as it is surrounded by densely populated areas and manufacturing plants. Surface water samples were collected monthly for 1 year from four sampling points at Pampulha Lake. Sample analysis was based on US Environmental Protection Agency Method 1633, which employs solid phase extraction followed by liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS). Species sensitivity distribution (SSD) curves were built to identify potentially susceptible species based on detected water concentrations. Bioaccumulation was estimated for fish tissue. Short-chain (perfluorobutanesulfonic acid, PFBS and perfluorohexanoic acid, PFHxA) and long-chain PFAS (perfluorodecanoic acid, PFDA; perfluorooctanoic acid, PFOA; perfluorododecanoic acid, PFDoA; and perfluorooctanesulfonic acid, PFOS) were detected at the µg L-1 range. Total PFAS concentrations in the wet season were generally higher than in the dry season, likely due to limited capacity of the treatment plant processing water from tributaries which receive raw sewage. More than 5 % of aquatic species are potentially susceptible to chronic effects of PFOS at detected concentrations (0.2-2.2 µg L-1). Predicted bioaccumulation of PFOS in fish was above advisory diet intake levels for humans. Results emphasize the need for studies related to PFAS occurrence in watersheds located in LMIC.


Assuntos
Monitoramento Ambiental , Fluorocarbonos , Lagos , Poluentes Químicos da Água , Fluorocarbonos/análise , Brasil , Lagos/química , Poluentes Químicos da Água/análise , Ácidos Alcanossulfônicos/análise , Animais , Caprilatos/análise , Peixes , Medição de Risco
14.
Eur J Pharmacol ; 978: 176788, 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-38977175

RESUMO

Drugs that act on α-adrenoceptors may contain morpholine and pyrimidinone heterocycles. The aim of this study was to synthesize a series of pyrimidinones (S6a-e and S8) and characterize their α-adrenoceptor activity. Cytotoxicity assays (MTT and LDH) were performed in A7r5 and HUVECs. Concentration-effect curves to phenylephrine (Phe) were performed in rat aortic rings in the presence of compounds S6a-e and S8 or vehicle. Nitric oxide (NO) production and NO stable metabolic products, nitrite and nitrate, expressed as total nitrogen oxides (NOx) were assessed in HUVECs by confocal microscopy with the DAF-2DA probe and by the Griess reaction, respectively. Molecular docking simulations were performed using the 6a compound and α2A-adrenoceptor. In the evaluated conditions, the percentage of viable cells and the release of LDH were similar between control cells and cells exposed to the tested pyrimidinones. S6d, S6e, S8, and the positive control prazosin (but not S6a, S6b, and S6c) decreased Phe-induced contractions in endothelium-denuded aortic rings. S6a, S6b, and S6c decreased Phe-induced contractions in endothelium-intact aortic rings. The effect of S6a was abolished by L-NAME. NO production and NOx levels were inhibited in the presence of the α2 receptor antagonist yohimbine and the NOS inhibitor L-NAME. The 6a docking simulation estimated that the mean binding free energy of the compound was lower than the estimated value for yohimbine. These data suggest that S6d, S6e, and S8 may be α1-adrenoceptor antagonists while S6a acts as an agonist of α2-adrenoceptors.


Assuntos
Células Endoteliais da Veia Umbilical Humana , Simulação de Acoplamento Molecular , Morfolinas , Pirimidinonas , Animais , Humanos , Ratos , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Pirimidinonas/farmacologia , Pirimidinonas/química , Morfolinas/farmacologia , Morfolinas/química , Óxido Nítrico/metabolismo , Masculino , Receptores Adrenérgicos alfa 2/metabolismo , Linhagem Celular , Aorta/efeitos dos fármacos , Aorta/citologia , Aorta/metabolismo , Ratos Wistar
15.
Toxicol In Vitro ; 99: 105884, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38945376

RESUMO

Hepatocellular carcinoma (HCC) is a significant contributor to cancer-related deaths globally. Systemic therapy is the only treatment option for HCC at an advanced stage, with limited therapeutic response. In this study, we evaluated the antitumor potential of four N-acylhydrazone (NAH) derivatives, namely LASSBio-1909, 1911, 1935, and 1936, on HCC cell lines. We have previously demonstrated that the aforementioned NAH derivatives selectively inhibit histone deacetylase 6 (HDAC6) in lung cancer cells, but their effects on HCC cells have not been explored. Thus, the present study aimed to evaluate the effects of NAH derivatives on the proliferative behavior of HCC cells. LASSBio-1911 was the most cytotoxic compound against HCC cells, however its effects were minimal on normal cells. Our results showed that LASSBio-1911 inhibited HDAC6 in HCC cells leading to cell cycle arrest and decreased cell proliferation. There was also an increase in the frequency of cells in mitosis onset, which was associated with disturbing mitotic spindle formation. These events were accompanied by elevated levels of CDKN1A mRNA, accumulation of CCNB1 protein, and sustained ERK1 phosphorylation. Furthermore, LASSBio-1911 induced DNA damage, resulting in senescence and/or apoptosis. Our findings indicate that selective inhibition of HDAC6 may provide an effective therapeutic strategy for the treatment of advanced HCC, including tumor subtypes with integrated viral genome. Further, in vivo studies are required to validate the antitumor effect of LASSBio-1911 on liver cancer.


Assuntos
Antineoplásicos , Carcinoma Hepatocelular , Proliferação de Células , Senescência Celular , Desacetilase 6 de Histona , Inibidores de Histona Desacetilases , Hidrazonas , Neoplasias Hepáticas , Desacetilase 6 de Histona/antagonistas & inibidores , Humanos , Carcinoma Hepatocelular/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Proliferação de Células/efeitos dos fármacos , Hidrazonas/farmacologia , Senescência Celular/efeitos dos fármacos , Inibidores de Histona Desacetilases/farmacologia , Linhagem Celular Tumoral , Antineoplásicos/farmacologia , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Inibidor de Quinase Dependente de Ciclina p21/genética , Ciclina B1/metabolismo , Ciclina B1/genética
16.
Biomolecules ; 14(5)2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38785957

RESUMO

RAMOSA1 (RA1) is a Cys2-His2-type (C2H2) zinc finger transcription factor that controls plant meristem fate and identity and has played an important role in maize domestication. Despite its importance, the origin of RA1 is unknown, and the evolution in plants is only partially understood. In this paper, we present a well-resolved phylogeny based on 73 amino acid sequences from 48 embryophyte species. The recovered tree topology indicates that, during grass evolution, RA1 arose from two consecutive SUPERMAN duplications, resulting in three distinct grass sequence lineages: RA1-like A, RA1-like B, and RA1; however, most of these copies have unknown functions. Our findings indicate that RA1 and RA1-like play roles in the nucleus despite lacking a traditional nuclear localization signal. Here, we report that copies diversified their coding region and, with it, their protein structure, suggesting different patterns of DNA binding and protein-protein interaction. In addition, each of the retained copies diversified regulatory elements along their promoter regions, indicating differences in their upstream regulation. Taken together, the evidence indicates that the RA1 and RA1-like gene families in grasses underwent subfunctionalization and neofunctionalization enabled by gene duplication.


Assuntos
Evolução Molecular , Filogenia , Proteínas de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Proteínas de Plantas/química , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Embriófitas/genética , Embriófitas/metabolismo , Sequência de Aminoácidos
17.
Eur J Cancer ; 205: 114103, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38729054

RESUMO

BACKGROUND: PTEN loss and aberrations in PI3K/AKT signaling kinases associate with poorer response to abiraterone acetate (AA) in metastatic castration-resistant prostate cancer (mCRPC). In this study, we assessed antitumor activity of the AKT inhibitor capivasertib combined with enzalutamide in mCRPC with prior progression on AA and docetaxel. METHODS: This double-blind, placebo-controlled, randomized phase 2 trial, recruited men ≥ 18 years with progressing mCRPC and performance status 0-2 from 15 UK centers. Randomized participants (1:1) received enzalutamide (160 mg orally, once daily) with capivasertib (400 mg)/ placebo orally, twice daily on an intermittent (4 days on, 3 days off) schedule. Primary endpoint was composite response rate (RR): RECIST 1.1 objective response, ≥ 50 % PSA decrease from baseline, or circulating tumor cell count conversion (from ≥ 5 at baseline to < 5 cells/7.5 mL). Subgroup analyses by PTENIHC status were pre-planned. RESULTS: Overall, 100 participants were randomized (50:50); 95 were evaluable for primary endpoint (47:48); median follow-up was 43 months. RR were 9/47 (19.1 %) enzalutamide/capivasertib and 9/48 (18.8 %) enzalutamide/placebo (absolute difference 0.4 % 90 %CI -12.8 to 13.6, p = 0.58), with similar results in the PTENIHC loss subgroup. Irrespective of treatment, OS was significantly worse for PTENIHC loss (10.1 months [95 %CI: 4.6-13.9] vs 14.8 months [95 %CI: 10.8-18]; p = 0.02). Most common treatment-emergent grade ≥ 3 adverse events for the combination were diarrhea (13 % vs 2 %) and fatigue (10 % vs 6 %). CONCLUSIONS: Combined capivasertib/enzalutamide was well tolerated but didn't significantly improve outcomes from abiraterone pre-treated mCRPC.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica , Benzamidas , Docetaxel , Nitrilas , Feniltioidantoína , Neoplasias de Próstata Resistentes à Castração , Pirimidinas , Humanos , Masculino , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Neoplasias de Próstata Resistentes à Castração/patologia , Feniltioidantoína/administração & dosagem , Feniltioidantoína/uso terapêutico , Feniltioidantoína/efeitos adversos , Docetaxel/administração & dosagem , Docetaxel/uso terapêutico , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Pessoa de Meia-Idade , Método Duplo-Cego , Pirimidinas/uso terapêutico , Pirimidinas/administração & dosagem , Pirimidinas/efeitos adversos , Androstenos/uso terapêutico , Androstenos/administração & dosagem , Idoso de 80 Anos ou mais , Pirróis
18.
Parasitol Res ; 123(5): 207, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38713234

RESUMO

Biomarkers are specific molecular, histological, or physiological characteristics of normal or pathogenic biological processes and are promising in the diagnosis of gastrointestinal nematodes (GINs). Although some biomarkers have been validated for infection by Ostertagia sp. in cattle raised in temperate regions, there is a lack of information for tropical regions. The aim of this project was to assess potential biomarkers and validate the most promising. In the first study, 36 bovines (Nelore breed) naturally infected by GINs were distributed into two groups: infected (not treated with anthelmintic) and treated (treated with fenbendazole on days 0, 7, 14, 21, 28, 42, and 56). The variables of interest were live weight, fecal egg count, hemogram, serum biochemical markers, phosphorus, gastrin, and pepsinogen. In the second step, pepsinogen was assessed in cattle of the Nelore breed distributed among three groups: infected (not treated with anthelmintic), MOX (treated with moxidectin), and IVM + BZD (treated with ivermectin + albendazole). In the first study, no difference between groups was found for weight, albumin, hematocrit (corpuscular volume [CV]), erythrocytes, or hemoglobin. Negative correlations were found between pepsinogen and both CV and albumin, and albumin was negatively correlated with the percentage of Haemonchus sp. in the fecal culture. Among the biomarkers, only pepsinogen differentiated treated and infected (beginning with the 28th day of the study). In the second study, a reduction in pepsinogen was found after anthelmintic treatment. Therefore, pepsinogen is a promising biomarker of worms in cattle naturally infected by the genera Haemonchus and Cooperia in tropical areas.


Assuntos
Biomarcadores , Doenças dos Bovinos , Fezes , Infecções por Nematoides , Clima Tropical , Animais , Bovinos , Doenças dos Bovinos/parasitologia , Doenças dos Bovinos/tratamento farmacológico , Biomarcadores/sangue , Infecções por Nematoides/veterinária , Infecções por Nematoides/parasitologia , Infecções por Nematoides/tratamento farmacológico , Fezes/parasitologia , Contagem de Ovos de Parasitas , Anti-Helmínticos/uso terapêutico , Nematoides/isolamento & purificação , Nematoides/classificação , Nematoides/efeitos dos fármacos , Gastroenteropatias/parasitologia , Gastroenteropatias/veterinária , Enteropatias Parasitárias/veterinária , Enteropatias Parasitárias/parasitologia , Fenbendazol/uso terapêutico
19.
Vet Res Commun ; 48(4): 2441-2455, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38819622

RESUMO

This study evaluated the effect of different supportive treatments on PCV replacement of dairy calves naturally infected with tick fever (TF) agents, and treated with diminazene and enrofloxacin. Five products were tested as supportive treatments in four experiments. In these experiments, we used Girolando female calves (Gyr × Holstein, genetic ratio of 15/16 and 31/32 Holstein) four to six months old, raised in pasture, naturally infected with TF agents, and infested with R. microplus. Supportive treatment was administered once on day 0 of the study concurrently with specific treatment targeting TF agents. The animals were observed on days 0, 3, and 7. Oral or intravenous administration of a vitamin complex and mineral salts enhanced the increase in PCV and biochemical analytes present in the serum of calves naturally infected with TF agents. No positive effect on PCV values was observed with the administration of (1) invigorating tonic: calcium, casein-peptides and vitamin B12, (2) iron-based stimulant tonic and (3) metabolic tonic: vitamin A, vitamin D, and a fraction of polyunsaturated fatty acids. Supplementation by injection with Type III iron resulted in increased hemoglobin and PCV in treated animals. However, these results did not occur with iron citrate. Therefore, more studies with Type III iron need to be performed. Supportive treatment conferred no advantage in animals with no history of reduced PCV.


Assuntos
Doenças dos Bovinos , Animais , Bovinos , Feminino , Doenças dos Bovinos/tratamento farmacológico , Doenças dos Bovinos/terapia , Hematócrito/veterinária , Diminazena/análogos & derivados , Diminazena/uso terapêutico , Diminazena/farmacologia , Enrofloxacina/uso terapêutico , Enrofloxacina/administração & dosagem , Infestações por Carrapato/veterinária , Infestações por Carrapato/tratamento farmacológico , Rhipicephalus
20.
ACS Chem Biol ; 19(4): 875-885, 2024 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-38483263

RESUMO

It is well established that oxaliplatin, one of the three Pt(II) anticancer drugs approved worldwide, and phenanthriplatin, an important preclinical monofunctional Pt(II) anticancer drug, possess a different mode of action from that of cisplatin and carboplatin, namely, the induction of nucleolar stress. The exact mechanisms that lead to Pt-induced nucleolar stress are, however, still poorly understood. As such, studies aimed at better understanding the biological targets of both oxaliplatin and phenanthriplatin are urgently needed to expand our understanding of Pt-induced nucleolar stress and guide the future design of Pt chemotherapeutics. One approach that has seen great success in the past is the use of Pt-click complexes to study the biological targets of Pt drugs. Herein, we report the synthesis and characterization of the first examples of click-capable phenanthriplatin complexes. Furthermore, through monitoring the relocalization of nucleolar proteins, RNA transcription levels, and DNA damage repair biomarker γH2AX, and by investigating their in vitro cytotoxicity, we show that these complexes successfully mimic the cellular responses observed for phenanthriplatin treatment in the same experiments. The click-capable phenanthriplatin derivatives described here expand the existing library of Pt-click complexes. Significantly they are suitable for studying nucleolar stress mechanisms and further elucidating the biological targets of Pt complexes.


Assuntos
Antineoplásicos , Nucléolo Celular , Compostos Organoplatínicos , Fenantridinas , Antineoplásicos/farmacologia , Antineoplásicos/metabolismo , Cisplatino/farmacologia , Compostos Organoplatínicos/química , Compostos Organoplatínicos/farmacologia , Oxaliplatina/farmacologia , Fenantridinas/síntese química , Fenantridinas/química , Fenantridinas/farmacologia , Química Click , Nucléolo Celular/efeitos dos fármacos , Nucléolo Celular/metabolismo
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