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1.
FASEB J ; 38(6): e23573, 2024 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-38526846

RESUMO

Familial hypercholesterolemia (FH) is one of the most prevalent monogenetic disorders leading to cardiovascular disease (CVD) worldwide. Mutations in Ldlr, encoding a membrane-spanning protein, account for the majority of FH cases. No effective and safe clinical treatments are available for FH. Adenine base editor (ABE)-mediated molecular therapy is a promising therapeutic strategy to treat genetic diseases caused by point mutations, with evidence of successful treatment in mouse disease models. However, due to the differences in the genomes between mice and humans, ABE with specific sgRNA, a key gene correction component, cannot be directly used to treat FH patients. Thus, we generated a knock-in mouse model harboring the partial patient-specific fragment and including the Ldlr W490X mutation. LdlrW490X/W490X mice recapitulated cholesterol metabolic disorder and clinical manifestations of atherosclerosis associated with FH patients, including high plasma low-density lipoprotein cholesterol levels and lipid deposition in aortic vessels. Additionally, we showed that the mutant Ldlr gene could be repaired using ABE with the cellular model. Taken together, these results pave the way for ABE-mediated molecular therapy for FH.


Assuntos
Hipercolesterolemia , Hiperlipoproteinemia Tipo II , Humanos , Camundongos , Animais , RNA Guia de Sistemas CRISPR-Cas , Hiperlipoproteinemia Tipo II/genética , Hiperlipoproteinemia Tipo II/terapia , Mutação , Hipercolesterolemia/genética , Colesterol , Receptores de LDL/genética , Receptores de LDL/metabolismo
2.
FASEB J ; 37(8): e23060, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37389931

RESUMO

CRISPR-Cas9 is a versatile gene editing tool with a broad application of basic research and clinical therapeutics. However, the potential impact caused by off-target effects remains a critical bottleneck. The small Cas9 ortholog from Staphylococcus auricularis (SauriCas9) was identified, which recognizes a 5'-NNGG-3' protospacer adjacent motif (PAM), exhibiting high activity for genome editing. Recently, we also reported enhanced-fidelity Staphylococcus aureus Cas9 (efSaCas9), which harbors a single mutation N260D. Protein sequence alignment revealed that SauriCas9 has 62.4% sequence identity with SaCas9. Because SauriCas9 is more flexible in recognizing the target sequence with PAM of 5'-NNGG-3' than SaCas9 of 5'-NNGRRT-3' PAM, we sought to test whether key mutation(N260D) or adjacent residue mutation in efSaCas9 can be appliable to SauriCas9. With this concept, two engineered SauriCas9 variants (SauriCas9-HF1, harboring the N269D mutation; SauriCas9-HF2, harboring the D270N mutation) dramatically improved targeting specificity by targeted deep sequencing and GUIDE-seq. At certain sites, reduced off-target effects (approximately 61.6- and 111.9-fold improvements) of SauriCas9-HF2 compared with wild-type SauriCas9 were observed. Overall, two identified SauriCas9 variants (SauriCas9-HF1 and SauriCas9-HF2) expand the utility of the CRISPR toolkit for research and therapeutic applications.


Assuntos
Sistemas CRISPR-Cas , Infecções Estafilocócicas , Humanos , Staphylococcus/genética , Staphylococcus aureus/genética
3.
Molecules ; 29(10)2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38792026

RESUMO

Ethanamizuril (EZL) is a new anticoccidial drug developed by our Shanghai Veterinary Research Institute. Since EZL is almost insoluble in water, we conducted a study to improve the solubility of EZL by forming inclusion complexes with ß-cyclodextrin (ß-CD) and hydroxypropyl-ß-cyclodextrin (HP-ß-CD). In this study, we performed molecular docking and then systematically compared the interactions of EZL with ß-CD and HP-ß-CD in both aqueous solution and the solid state, aiming to elucidate the solubilization effect and mechanism of cyclodextrins (CDs). The interactions were also examined in the solid state using DSC, PXRD, and FT-IR. The interactions of EZL with CDs in an aqueous solution were investigated using PSA, UV-vis spectroscopy, MS, 1H NMR, and 2D ROESY. The results of phase solubility experiments revealed that both ß-CD and HP-ß-CD formed inclusion complexes with EZL in a 1:1 molar ratio. Among them, HP-ß-CD exhibited higher Kf (stability constant) and CE (complexation efficiency) values as well as a stronger solubilization effect. Furthermore, the two cyclodextrins were found to interact with EZL in a similar manner. The results of our FT-IR and 2D ROESY experiments are in agreement with the theoretical results derived from molecular simulations. These results indicated that intermolecular hydrogen bonds existing between the C=O group on the triazine ring of EZL and the O-H group of CDs, as well as the hydrophobic interactions between the hydrogen on the benzene ring of EZL and the hydrogen of CDs, played crucial roles in the formation of EZL/CD inclusion complexes. The results of this study can lay the foundation for the future development of high-concentration drinking water delivery formulations for EZL.

4.
J Antimicrob Chemother ; 77(12): 3312-3320, 2022 11 28.
Artigo em Inglês | MEDLINE | ID: mdl-36173387

RESUMO

OBJECTIVES: Niclosamide is commonly used as an antiparasitic drug in veterinary clinics. The objectives of this study were to evaluate the efficacy of niclosamide against resistant Gram-positive bacteria in vitro and in an in vivo experimental model of topical bacterial infection. Moreover, to study the antibacterial mechanism of niclosamide to Staphylococcus aureus. METHODS: A mouse topical infection model was established to detect the antibacterial activity of niclosamide in vivo. The antimicrobial mechanism was probed by visualizing the bacterial morphologies using scanning electron microscopy and transmission electron microscopy. Moreover, the haemolytic assay and western blotting analysis were performed to evaluate whether niclosamide could inhibit the secretion of alpha-haemolysin (α-HL) from S. aureus. RESULTS: The MICs of niclosamide were below 0.5 mg/L for Gram-positive bacteria, showing excellent antibacterial activity in vitro. The in vivo antibacterial activity results indicated that niclosamide treatment at 10 mg/kg of body weight caused a significant reduction in the abscess area and the number of S. aureus cells. Moreover, the antibacterial mechanism of niclosamide showed that the surface morphology of S. aureus displayed noticeable shrinkage, with an increasing number of small vacuole-like structures observed as the drug concentration increased. Intracellular ATP levels were found to decrease in a niclosamide dose-dependent manner. Haemolysis and western blotting analyses revealed that niclosamide inhibited the haemolytic activity of S. aureus by inhibiting α-HL expression under subinhibitory concentration conditions. CONCLUSIONS: Niclosamide has significant potential for development into drugs that prevent and treat diseases caused by Gram-positive bacteria such as Staphylococcus and Streptococcus.


Assuntos
Reposicionamento de Medicamentos , Infecções por Bactérias Gram-Positivas , Niclosamida , Animais , Camundongos , Antibacterianos/farmacologia , Bactérias Gram-Positivas/efeitos dos fármacos , Infecções por Bactérias Gram-Positivas/tratamento farmacológico , Infecções por Bactérias Gram-Positivas/microbiologia , Testes de Sensibilidade Microbiana , Niclosamida/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Resultado do Tratamento , Modelos Animais de Doenças
5.
Microb Pathog ; 173(Pt A): 105823, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36243384

RESUMO

Coccidiostat and antibiotics are widely used in poultry industry, but their effects on cecum microbial community and metabolomics in chickens infected with coccidia have been rarely studied. In this study, we analyzed the changes of microbiota and metabolomic which associated with Eimeria tenella infection in 8 days of age chickens in the presence or absence of ethanamizuril, sulfachlorpyridazine or their combinations treatment for 3 consecutive days. 16S rRNA gene sequencing and LC-MS/MS analyses were used to profile the cecal microbiome and metabolome in each group of chickens on 7 days post-infection. The results showed that coccidial infection induced significant perturbations in the distribution of microbial taxonomy and the metabolism of physiological functional molecules in cecal contents. Ethanamizuril treatment seemed to transform microbiota into a steady state conducive to animal health, and sulfachlorpyridazine treatment alleviated the growth of potentially harmful bacteria such as Escherichia-Shigella. The change trends of metabolites such as n-carbamoylglutamic acid were consistent with the anticoccidial effect of ethanamizuril. The combinations of ethanamizuril and sulfachlorpyridazine at low-dose had little effect on gut microbiota, metabolism and anticoccidial effect. These data indicate that the cecal microbiota and metabolic status of chickens infected with E. tenella following ethanamizuril treatment could be used to monitor the response to drug efficacy. This study provides a new system approach to elucidate the microbiota, metabolic and therapeutic effects of the combination of coccidiostat and antibiotics in the context of avian coccidiosis.


Assuntos
Coccidiose , Coccidiostáticos , Eimeria tenella , Microbioma Gastrointestinal , Doenças das Aves Domésticas , Sulfacloropiridazina , Animais , Eimeria tenella/genética , Galinhas/microbiologia , Sulfacloropiridazina/uso terapêutico , Coccidiostáticos/farmacologia , Coccidiostáticos/uso terapêutico , RNA Ribossômico 16S/genética , Cromatografia Líquida , Doenças das Aves Domésticas/tratamento farmacológico , Doenças das Aves Domésticas/microbiologia , Espectrometria de Massas em Tandem , Ceco/microbiologia , Coccidiose/tratamento farmacológico , Coccidiose/veterinária , Microbioma Gastrointestinal/genética , Metabolômica , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico
6.
Acta Biochim Biophys Sin (Shanghai) ; 54(11): 1630-1636, 2022 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-36604145

RESUMO

Influenza is a significant public health challenge because of the emergence of antigenically shifted or highly virulent strains. The neuraminidase inhibitor oseltamivir is used as an antiviral drug in clinical treatment. However, its therapeutic effects can be greatly compromised by the emergence of drug-resistant mutant viruses. Thus, there is an urgent need to distinguish drug-resistant strains with a simple method. To address this, in the present study, we develop a rapid, sensitive and convenient molecular diagnosis method based on CRISPR/Cas12a technology and lateral flow detection (LFD). By targeting mutant sequences amplified by recombinase polymerase amplification (RPA) reaction, crRNA is designed to develop the CRISPR/Cas12a assay, and 2000 copies can be directly observed by the naked eye under blue light-emitting diode (LED) light. Combined with LFD, the limit of detection of RPA-CRISPR/Cas12a-LFD is about 20 copies of target sequence per reaction. Collectively, RPA-CRISPR/Cas12a-LFD method provides a novel alternative for the sensitive, specific and portable detection to diagnose oseltamivir-resistant mutant strains.


Assuntos
Técnicas de Amplificação de Ácido Nucleico , Vírus , Técnicas de Amplificação de Ácido Nucleico/métodos , Oseltamivir/farmacologia , Sistemas CRISPR-Cas , Recombinases/metabolismo , Vírus/metabolismo
7.
BMC Vet Res ; 16(1): 444, 2020 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-33203451

RESUMO

BACKGROUND: Triazine coccidiostats are widely used in chickens and turkeys for coccidiosis control. Ethanamizuril is a novel triazine compound that exhibits anticoccidial activity in poultry. This study was designed to evaluate the subchronic toxicity of ethanamizuril in beagle dogs at doses of 12, 60 or 300 mg/kg/day in diet for 90 days. RESULTS: Ethanamizuril was well tolerated at low and middle dosages in beagle dogs, and no drug-related toxical effects were observaed in terms of survival, clinical observations, organs weight and damage in these dose groups. However, in high dose administration group, food consumption and histologic changes in kidneys were noticed in both sexes of beagle dog, although the renal lesions were finally resolved at the end of 4 weeks exposure of ethanamizuril. CONCLUSIONS: No-observed-adverse-effect level (NOAEL) was considered for ethanamizuril at dose of 60 mg/kg/day in Beagle dog. This result added toxicity effects of ethanamizuril to the safety database, which might guide safely using of ethanamizuril as a novel coccidiostat.


Assuntos
Coccidiostáticos/toxicidade , Triazinas/toxicidade , Administração Oral , Animais , Coccidiostáticos/administração & dosagem , Cães , Relação Dose-Resposta a Droga , Comportamento Alimentar/efeitos dos fármacos , Feminino , Rim/efeitos dos fármacos , Masculino , Triazinas/administração & dosagem
8.
Regul Toxicol Pharmacol ; 111: 104550, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31843591

RESUMO

In the current study, to support the safety assessment of ethanamizuril as a new potent anticoccidial agent of triazine compounds, a 90-day repeated-dose oral toxicity assay of ethanamizuril was investigated. Treatment related clinical signs of alopecia on back and neck have been observed in some male and female at the 65 and 130 mg/kg dose groups. The body weight and feed conversion efficacy of 65 and 130 mg/kg females and 65 mg/kg males were significantly increase than those of the control in treatment time, but noted decreased in the 130 mg/kg males. Dose related changes of hematologic and biochemical parameters such as MCV, MCH, TG, and the significant increased in the organ weight and the relative organ weight of the liver, kidney, heart, lung and spleen in both genders in the 65 and 130 mg/kg treated groups were observed. Furthermore, histopathological observations revealed that 65 and 130 mg/kg ethanamizuril induced pathological damage such as hepatocyte steatosis and focal necrosis, renal tubular atrophy, tubule protein casts. Fortunately, the observed toxicities were recoverable in convalescence. The results indicated that liver, kidneys and lung were the main target organs. The NOAEL of ethanamizuril for rats was estimated to be 20 mg/kg dietary dose level.


Assuntos
Túbulos Renais/efeitos dos fármacos , Fígado/efeitos dos fármacos , Pulmão/efeitos dos fármacos , Triazinas/toxicidade , Administração Oral , Animais , Relação Dose-Resposta a Droga , Feminino , Túbulos Renais/patologia , Fígado/patologia , Pulmão/patologia , Masculino , Ratos , Ratos Sprague-Dawley , Testes de Toxicidade Subcrônica , Triazinas/administração & dosagem , Triazinas/síntese química
9.
Regul Toxicol Pharmacol ; 113: 104623, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32088183

RESUMO

In the current study, to support the safety assessment of ethanamizuril as a new potent anticoccidial agent of triazine compounds, a reproductive toxicity and teratogenic potential assay of ethanamizuril was investigated. Groups of 30 males and 30 females were administered 0, 0.02, 0.1 or 0.2 mg/ml ethanamizuril by gastric incubation through a 10-week prebreed period as well as during mating, gestation, parturition and lactation in any generation. Compared to the control group, no test compound-related changes in copulation index, fertility index, gestation length, litter size, pup weight, pup sex ratio, pup viability, epididymal sperm counts or motility or other functional reproductive measures were noted in any generation, except few significant changes in high dose group in the number of sperm motility at III level in F0 males and the body weights of GD14 and GD21 in F1 rats. There were no compound-related necropsy findings or effects on organ weight. Histopathologic examinations revealed no evidence of compound-related changes in any organs including the reproductive organs of both sexes. In conclusion, long-term administrated 0.2, 1.0 and 2.0 mg/kg of ethanamizuril by means of oral gavage did not affect the reproduction of Sprague-Dawley rats and the development ability of their offspring under the experimental conditions.


Assuntos
Coccidiostáticos/administração & dosagem , Triazinas/administração & dosagem , Administração Oral , Animais , Coccidiostáticos/química , Relação Dose-Resposta a Droga , Feminino , Masculino , Estrutura Molecular , Gravidez , Ratos , Ratos Sprague-Dawley , Triazinas/química
10.
Parasitol Res ; 119(5): 1653-1661, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32219548

RESUMO

Ethanamizuril (EZL) is a novel triazine compound with excellent anticoccidial activity. We carried out a preliminary investigation of the effects of EZL on the different life cycle stages of Eimeria tenella. EZL mainly acted on the schizogony stage, with peak activity during the second-generation merozoite stage. We also studied the possible target of EZL by identifying the majorly differentially expressed gene affected by EZL in second-generation merozoites using real-time polymerase chain reaction, and screening for surface antigen proteins (SAGs). The relative expression levels of SAGs were compared by Western blot analysis showing that expression levels of surface antigen family member (SAGfm) and SAG19 were significantly downregulated by EZL. Immunofluorescence analysis indicated that SAGfm and SAG19 were localized on the surface of second-generation merozoites. In addition, fluorescence signals were significantly stronger in second-generation merozoites of infected non-medicated control (INC) group compared with that of the EZL group. Therefore, it was speculated that SAGs might be a potential target of EZL action. The inhibitory effects of anticoccidial drugs on SAG levels in coccidia thus warrant further research.


Assuntos
Coccidiose/tratamento farmacológico , Eimeria tenella/efeitos dos fármacos , Doenças das Aves Domésticas/prevenção & controle , Triazinas/farmacologia , Animais , Antígenos de Superfície/metabolismo , Western Blotting , Galinhas/parasitologia , Coccidiose/parasitologia , Estágios do Ciclo de Vida/efeitos dos fármacos , Merozoítos/efeitos dos fármacos , Proteínas de Protozoários/genética , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real
11.
J Vet Pharmacol Ther ; 43(4): 331-338, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32374465

RESUMO

Ethanamizuril is a new triazine compound that shows potential for application in novel anticoccidial treatment. In this study, a pharmacokinetic model of ethanamizuril was established on the basis of the blood concentration of 81 experimental animals. The final model showed that ethanamizuril was distributed as a two-compartment model with first-order absorption after oral administration in chickens. Its clearance rate and volumn of central compartment distribution (Vc ) were affected by age and body weight, and volumn of central compartment distribution (Vc ) and volume of peripheral compartment distribution(Vp ) were influenced by weight and infection. External verification revealed that the model had good prediction accuracy and stability.


Assuntos
Galinhas/metabolismo , Coccidiose/veterinária , Doenças das Aves Domésticas/tratamento farmacológico , Triazinas/farmacocinética , Animais , Galinhas/sangue , Cromatografia Líquida/métodos , Cromatografia Líquida/veterinária , Coccidiose/tratamento farmacológico , Coccidiose/metabolismo , Modelos Biológicos , Estrutura Molecular , Doenças das Aves Domésticas/metabolismo , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem/métodos , Espectrometria de Massas em Tandem/veterinária , Triazinas/administração & dosagem , Triazinas/sangue , Triazinas/química
12.
Biomed Chromatogr ; 33(11): e4652, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31322281

RESUMO

Ethanamizuril is a new triazine compound that has the potential to be a novel anticoccidial drug. Toxicological studies in experimental rats were performed to understand the safety profile of ethanamizuril for drug product development. In this study, a novel, selective and accurate ultra-performance liquid chromatography tandem mass spectrometry method has been developed for the determination of ethanamizuril concentrations in rat plasma. With 4-nitro-o-cresol as an internal standard, sample pretreatment involved a one-step extraction with acetonitrile of 100 µL plasma. The detection was carried out by electrospray ionization mass spectrometry in negative ion mode with selected ion recording. The standard curves were linear (r2 ≥ 0.999) over the concentration range of 0.1-100 µg/mL. The relative standard deviations of intra- and inter-day precisions were less than 8.4 and 8.87%, respectively. The mean extraction recovery of ethanamizuril from rat plasma was 97.68-102.57%. The method was fully validated and successfully applied to monitor plasma concentrations of ethanamizuril in a short-term toxicity study and two-generation reproduction toxicity study. The result of the study confirmed that the elimination of ethanamizuril in rats is slow.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Coccidiostáticos/sangue , Espectrometria de Massas em Tandem/métodos , Triazinas/sangue , Animais , Coccidiostáticos/química , Coccidiostáticos/farmacocinética , Feminino , Limite de Detecção , Modelos Lineares , Masculino , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos Testes , Espectrometria de Massas por Ionização por Electrospray , Triazinas/química , Triazinas/farmacocinética
13.
Parasitol Res ; 116(8): 2167-2174, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28589234

RESUMO

Nitromezuril is a novel triazine compound for preventing coccidiosis in broiler chickens. A single treatment of chickens inoculated with Eimeria tenella during the endogenous phase were used to evaluate the developmental stages of action of nitromezuril by clinically anticoccidial indices and histopathology. Results showed that a single dose of nitromezuril at 5 mg/kg b.w. during 56 to 80 h post-inoculation can most effectively prevent weight loss and reduce both oocyst shedding and caecal lesions. The anticoccidial index reached the level of middle efficacy. Histological examinations indicated that administration of nitromezuril during 44 to 104 h after infection significantly reduced the merozoite population and the pathological damage to the caecum. Nitromezuril treatment could disturb the process of schizonts division into schizoites and produce abnormal schizonts. Overall, nitromezuril may exert its effects during the entire endogenous stage of the parasites but the schizogony stages were intrinsically more vulnerable. Nitromezuril is a potential novel anticoccidial agent suitable for further development.


Assuntos
Galinhas , Coccidiose/veterinária , Coccidiostáticos/farmacologia , Eimeria tenella/efeitos dos fármacos , Doenças das Aves Domésticas/tratamento farmacológico , Triazinas/farmacologia , Animais , Ceco/parasitologia , Ceco/patologia , Galinhas/parasitologia , Coccidiose/tratamento farmacológico , Coccidiose/patologia , Merozoítos/efeitos dos fármacos , Oocistos/efeitos dos fármacos , Doenças das Aves Domésticas/parasitologia , Doenças das Aves Domésticas/patologia , Esquizontes/efeitos dos fármacos
14.
Parasitol Res ; 115(3): 1245-52, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26706906

RESUMO

To explore the primary stage or site of action of acetamizuril (AZL), a novel triazine anticoccidial compound, the ultrastructural development of Eimeria tenella at different endogenous stages was studied in experimentally infected chickens treated with a single oral dose of 15 mg/kg AZL. As a result of drug action, the differentiations of second-generation schizonts and microgamonts were largely inhibited and merozoites became irregular in shape. Meanwhile, the outer membrane blistering and perinuclear space enlargement were obvious in the second-generation schizonts and microgamonts, which were never observed in the classic triazine anticoccidiosis drug diclazuril-treated E. tenella. The chromatin aggregation, anachromasis, and marginalization were visible in merozoites and microgamonts. Furthermore, the abnormal evagination of microgametes finally resulted in the degeneration of microgamonts and the failure of subsequent fertilization. The most marked micromorphological alteration occurring in the macrogamonts was the WFB2. Even if the fertilization occurred, the formation of oocyst wall became malformed and the zygote proceeded to the obvious degeneration. In addition, mitochondria swelling and cytoplasm vacuolization were discerned in respective intracellular stages, while endoplasmic reticulum and Golgi body swelling was less seen. These alterations may be the causes leading to the final death of E. tenella and also provide some information for further exploring the mechanism of action of AZL at the molecular level.


Assuntos
Coccidiose/veterinária , Coccidiostáticos/farmacologia , Eimeria tenella/efeitos dos fármacos , Triazinas/farmacologia , Animais , Ceco/parasitologia , Ceco/ultraestrutura , Galinhas , Coccidiose/tratamento farmacológico , Coccidiose/parasitologia , Eimeria tenella/crescimento & desenvolvimento , Eimeria tenella/ultraestrutura , Retículo Endoplasmático/efeitos dos fármacos , Retículo Endoplasmático/ultraestrutura , Complexo de Golgi/efeitos dos fármacos , Complexo de Golgi/ultraestrutura , Merozoítos/efeitos dos fármacos , Merozoítos/ultraestrutura , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/ultraestrutura , Nitrilas/farmacologia , Oocistos , Distribuição Aleatória , Esquizontes/efeitos dos fármacos , Esquizontes/ultraestrutura
15.
Regul Toxicol Pharmacol ; 71(3): 585-9, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25645284

RESUMO

Nitromezuril (NZL) is a novel triazine compound that exhibits remarkable anticoccidial activity. However, mutagenicity and genotoxicity of NZL have not been evaluated to date. This study evaluated the potential risks of NZL by testing for bacterial reverse mutation (Ames), mouse sperm abnormality (SA), bone marrow micronucleus (MN) and chromosomal aberration (CA). Mice were orally administered with NZL at 385, 192 and 96 mg/kg, corresponding to 0.5 ×, 0.25 × and 0.125 × the LD50 of NZL, respectively. No significant increases in SA and CA were found in mice treated with NZL for 5d and 3d, respectively (P>0.05). NZL at 96-385 mg/kg did not have significant influence on micronucleated polychromatic erythrocyte counts (P>0.05). These results suggest that NZL is not genotoxic. However, Ames test results were positive both with and without the S9 system for Salmonella typhimurium TA98 and TA100, suggesting that NZL may be mutagenic. The mutagenic effects of NZL were different in in vitro and in vivo assays. Further studies should be conducted to confirm the safety of using and developing NZL as a novel anticoccidial drug.


Assuntos
Aberrações Cromossômicas/induzido quimicamente , Coccidiostáticos/toxicidade , DNA Bacteriano/efeitos dos fármacos , Micronúcleos com Defeito Cromossômico/induzido quimicamente , Mutação , Salmonella typhimurium/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos , Triazinas/toxicidade , Administração Oral , Animais , Coccidiostáticos/administração & dosagem , DNA Bacteriano/genética , Relação Dose-Resposta a Droga , Feminino , Dose Letal Mediana , Masculino , Camundongos , Testes para Micronúcleos , Medição de Risco , Salmonella typhimurium/genética , Espermatozoides/patologia , Fatores de Tempo , Triazinas/administração & dosagem
16.
Rapid Commun Mass Spectrom ; 28(15): 1723-34, 2014 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-24975253

RESUMO

RATIONALE: Nitromezuril is a novel triazine compound possessing remarkable anticoccidial activity that could have possible future use in the prevention of coccidiosis; however, its metabolic characteristics have still not been revealed. METHODS: In the present study, the in vitro metabolism of nitromezuril in HepG2 cells, rat S9 and primary hepatocytes was investigated using high-performance liquid chromatography with electrospray ionization tandem mass spectrometry. The structures of metabolites and their product ions were easily and reliably characterized based on the accurate MS(2) spectra and known structure of nitromezuril. RESULTS: As expected, three metabolites (M1-M3) were detected in a HepG2 cells system, one metabolite was respectively detected and identified as M1 in rat S9 and M2 in rat primary hepatocytes. M1 and M2 were confirmed respectively based on comparing their retention times, full scan, product ion scan with available authentic standards and M3 was tentatively identified as hydroxyl compound of M2. CONCLUSIONS: Pathways of nitromezuril were reported for the first time and no obvious species difference was shown. The proposed metabolic pathways of nitromezuril can be expected to play a key role in pharmacodynamics and food safety evaluations.


Assuntos
Cromatografia Líquida/métodos , Coccidiostáticos/farmacocinética , Hepatócitos/metabolismo , Espectrometria de Massas em Tandem/métodos , Triazinas/farmacocinética , Animais , Células Cultivadas , Humanos , Ratos , Especificidade da Espécie
17.
Cell Biol Toxicol ; 30(6): 313-29, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25223261

RESUMO

Quinocetone, a new quinoxaline 1,4-dioxide derivative used in food-producing animals in China, exerts genotoxic effects on HepG2 cells. It triggers significant cytotoxicity and genotoxicity in vitro, but the detailed mechanism by which quinocetone induces adverse biological effects is not yet known. We analyzed the mechanisms behind quinocetone intoxication by investigating oxidative stress based on non-enzymatic and enzymatic antioxidant activities, and by identifying differentially regulated genes of HepG2 cells exposed to quinocetone using polymerase chain reaction (PCR)-based suppression subtractive hybridization to illustrate the toxicity mechanism of quinocetone. Meanwhile, the characteristics of oxidative stress and differentially regulated genes induced by quinocetone metabolites, 1,4-bisdesoxyquinocetone and 3-methylquinoxaline-2-carboxylic acid, were investigated too. Results showed that quinocetone damaged the antioxidant defense abilities of HepG2 cells by reducing the activities of endogenous antioxidant enzymes, lowering glutathione concentration, and elevating malondialdehyde level. We identified 160 quinocetone-responsive genes that were associated with cell proliferation, glucose metabolism, oxidative stress, and apoptosis, such as NAD(P)H dehydrogenase, quinone 1; and prolyl 4-hydroxylase, beta polypeptide. The expressions of some differentially regulated genes were confirmed by real-time reverse transcription-polymerase chain reaction. However, quinocetone metabolites showed little effects on HepG2 cells. These results showed that reactive oxygen species were the key mediators of quinocetone cytotoxicity in HepG2 cells and that c-MYC-dependent activation of the mitochondrial apoptotic pathway may be associated with quinocetone-induced toxicity.


Assuntos
Antibacterianos/toxicidade , Expressão Gênica/efeitos dos fármacos , Oxidantes/toxicidade , Quinoxalinas/toxicidade , Apoptose/efeitos dos fármacos , Catalase/genética , Catalase/metabolismo , Proliferação de Células/efeitos dos fármacos , Dano ao DNA , FMN Redutase/genética , FMN Redutase/metabolismo , Glucose/metabolismo , Glutationa/metabolismo , Glutationa Peroxidase/genética , Glutationa Peroxidase/metabolismo , Células Hep G2 , Humanos , Malondialdeído/metabolismo , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Estresse Oxidativo , Prolil Hidroxilases/genética , Prolil Hidroxilases/metabolismo , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , Espécies Reativas de Oxigênio/agonistas , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo
18.
ACS Appl Mater Interfaces ; 16(5): 5522-5535, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38266749

RESUMO

Multidrug-resistant (MDR) pathogens pose a serious threat to the health and life of humans, necessitating the development of new antimicrobial agents. Herein, we develop and characterize a panel of nine amino acid peptides with a cation end motif. Bioactivity analysis revealed that the short peptide containing "RWWWR" as a central motif harboring mirror structure "KXR" unit displayed not only high activity against MDR planktonic bacteria but also a clearance rate of 92.33% ± 0.58% against mature biofilm. Mechanically, the target peptide (KLR) killed pathogens by excessively accumulating reactive oxygen species and physically disrupting membranes, thereby enhancing its robustness for controlling drug resistance. In the animal model of sepsis infection by MDR bacteria, the peptide KLR exhibited strong therapeutic effects. Collectively, this study provided the dominant structure of short antimicrobial peptides (AMPs) to replenish our arsenals for combating bacterial infections and illustrated what could be harnessed as a new agent for fighting MDR bacteria.


Assuntos
Anti-Infecciosos , Infecções Bacterianas , Humanos , Animais , Peptídeos Catiônicos Antimicrobianos/farmacologia , Peptídeos Catiônicos Antimicrobianos/química , Farmacorresistência Bacteriana Múltipla , Anti-Infecciosos/farmacologia , Infecções Bacterianas/tratamento farmacológico , Testes de Sensibilidade Microbiana , Bactérias , Antibacterianos/farmacologia , Antibacterianos/química
19.
Vet Res ; 44: 29, 2013 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-23651214

RESUMO

In mammalian cells, GAPDH (glyceraldehyde-3-phosphate dehydrogenase) has recently been shown to be implicated in numerous apoptotic paradigms, especially in neuronal apoptosis, and has been demonstrated to play a vital role in some neurodegenerative disorders. However, this phenomenon has not been reported in protists. In the present study, we report for the first time that such a mechanism is involved in diclazuril-induced apoptosis in Eimeria tenella (E. tenella). We found that upon treatment of parasites with diclazuril, the expression levels of GAPDH transcript and protein were significantly increased in second-generation merozoites. Then, we examined the subcellular localization of GAPDH by fluorescence microscopy and Western blot analysis. The results show that a considerable amount of GAPDH protein appeared in the nucleus within diclazuril-treated second-generation merozoites; in contrast, the control group had very low levels of GAPDH in the nucleus. The glycolytic activity of GAPDH was kinetically analyzed in different subcellular fractions. A substantial decrease (48.5%) in glycolytic activity of GAPDH in the nucleus was displayed. Moreover, the activities of caspases-3, -9, and -8 were measured in cell extracts using specific caspase substrates. The data show significant increases in caspase-3 and caspase-9 activities in the diclazuril-treated group.


Assuntos
Apoptose/efeitos dos fármacos , Coccidiostáticos/farmacologia , Eimeria tenella/efeitos dos fármacos , Gliceraldeído-3-Fosfato Desidrogenases/metabolismo , Nitrilas/farmacologia , Triazinas/farmacologia , Animais , Caspases/metabolismo , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Galinhas , Eimeria tenella/crescimento & desenvolvimento , Eimeria tenella/fisiologia , Masculino , Merozoítos/efeitos dos fármacos , Merozoítos/crescimento & desenvolvimento , Merozoítos/fisiologia , Distribuição Aleatória
20.
ACS Appl Mater Interfaces ; 15(22): 26273-26284, 2023 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-37230936

RESUMO

Chronic wound infection caused by multidrug-resistant bacteria is a major threat globally, leading to high mortality rates and a considerable economic burden. To address it, an innovative supramolecular nanofiber hydrogel (Hydrogel-RL) harboring antimicrobial peptides was developed based on the novel arginine end-tagging peptide (Pep 6) from our recent study, triggering cross-linking. In vitro results demonstrated that Hydrogel-RL can sustain the release of Pep 6 up to 120 h profiles, which is biocompatible and exhibits superior activity for methicillin-resistant Staphylococcus aureus (MRSA) biofilm inhibition and elimination. A single treatment of supramolecular Hydrogel-RL on an MRSA skin infection model revealed formidable antimicrobial activity and therapeutic effects in vivo. In the chronic wound infection model, Hydrogel-RL promoted mouse skin cell proliferation, reduced inflammation, accelerated re-epithelialization, and regulated muscle and collagen fiber formation, rapidly healing full-thickness skin wounds. To show its vehicle property for wound infection combined therapy, etamsylate, an antihemorrhagic drug, was loaded into the porous network of Hydrogel-RL, which demonstrated improved hemostatic activity. Collectively, Hydrogel-RL is a promising clinical candidate agent for functional supramolecular biomaterials designed for combating multidrug-resistant bacteria and rescuing stalled healing in chronic wound infections.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Infecção dos Ferimentos , Animais , Camundongos , Preparações de Ação Retardada/farmacologia , Hidrogéis/química , Peptídeos/farmacologia , Peptídeos/uso terapêutico , Infecção dos Ferimentos/tratamento farmacológico , Antibacterianos/química
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