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1.
Zhongguo Zhong Yao Za Zhi ; 48(1): 126-139, 2023 Jan.
Artigo em Zh | MEDLINE | ID: mdl-36725265

RESUMO

UHPLC-Q-Exactive Orbitrap MS/MS was used to systematically analyze and compare the alkaloids in Aconiti Kusnezoffii Radix, Aconiti Radix, and Aconiti Lateralis Radix Praeparata. After the samples were pretreated in the solid-phase extraction cartridges, 0.1% ammonium hydroxide(A)-acetonitrile(B) was used for gradient elution. The LC-MS method for characterization of alkaloids in the three herbal medicines was established in ESI positive ion mode to collect high resolution MS data of reference substances and samples. On the basis of the information of reference substance cracking behavior, retention time, accurate molecular mass, and related literature, a total of 155 alkaloids were identified in Aconiti Kusnezoffii Radix, Aconiti Radix, and Aconiti Lateralis Radix Prae-parata. Specifically, 130, 127, and 92 alkaloids were identified in Aconiti Kusnezoffii Radix, Aconiti Radix, and Aconiti Lateralis Radix Praeparata, respectively. Monoester alkaloids and amino-alcohol alkaloids were dominant in the three herbal medicines, and the alkaloids in Aconiti Kusnezoffii Radix and Aconiti Radix were similar. This paper can provide a reference for elucidating the pharmacological effects and clinical application differences of the three herbal medicines produced from plants of Aconitum.


Assuntos
Aconitum , Alcaloides , Medicamentos de Ervas Chinesas , Plantas Medicinais , Espectrometria de Massas em Tandem , Cromatografia Líquida de Alta Pressão/métodos
2.
Biomed Chromatogr ; 36(3): e5281, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34792824

RESUMO

Myricetin is a common natural flavonoid compound with various pharmacological activities. However, the metabolite characterization of this substance remains inadequate. In this study, a simple and rapid system strategy based on UHPLC-Q-Exactive Orbitrap mass spectrometry combining parallel reaction monitoring mode was established to screen and identify myricetin metabolites in rat urine, plasma and feces after oral administration. A total of 38 metabolites were fully or partially characterized based on their accurate mass, characteristic fragment ions, retention times, corresponding cLogP values, etc. These metabolites were presumed to be generated through glucuronidation, glucosylation, sulfation, dihydroxylation, acetylation, hydrogenation, hydroxylation and their composite reactions. In addition, the characteristic fragmentation pathways of flavonoids with more metabolites were summarized for the subsequent metabolite identification. The study provides an overall metabolic profile of myricetin, which would be of great help in predicting the in vivo pharmacokinetic profiles and understanding the action mechanism of this active ingredient.


Assuntos
Flavonoides , Animais , Cromatografia Líquida de Alta Pressão/métodos , Fezes/química , Flavonoides/análise , Ratos , Ratos Sprague-Dawley
3.
Molecules ; 27(21)2022 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-36364106

RESUMO

Naringenin (5,7,4'-trihydroxyflavanone), belonging to the flavanone subclass, is associated with beneficial effects such as anti-oxidation, anticancer, anti-inflammatory, and anti-diabetic effects. Drug metabolism plays an essential role in drug discovery and clinical safety. However, due to the interference of numerous endogenous substances in metabolic samples, the identification and efficient characterization of drug metabolites are difficult. Here, ultra-high-performance liquid chromatography (UHPLC) coupled with high-resolution mass spectrometry was used to obtain mass spectral information of plasma (processed by three methods), urine, feces, liver tissue, and liver microsome samples. Moreover, a novel analytical strategy named "ion induction and deduction" was proposed to systematically screen and identify naringenin metabolites in vivo and in vitro. The analysis strategy was accomplished by the establishment of multiple "net-hubs" and the induction and deduction of fragmentation behavior. Finally, 78 naringenin metabolites were detected and identified from samples of rat plasma, urine, feces, liver tissue, and liver microsomes, of which 67 were detected in vivo and 13 were detected in vitro. Naringenin primarily underwent glucuronidation, sulfation, oxidation, methylation, ring fission, and conversion into phenolic acid and their composite reactions. The current study provides significant help in extracting target information from complex samples and sets the foundation for other pharmacology and toxicology research.


Assuntos
Flavanonas , Ratos , Animais , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas , Microssomos Hepáticos
4.
Zhongguo Zhong Yao Za Zhi ; 47(15): 4202-4213, 2022 Aug.
Artigo em Zh | MEDLINE | ID: mdl-36046911

RESUMO

This study aims to identify and analyze the metabolites of imperatorin in rats by UHPLC-Q-Exactive Orbitrap MS. Specifically, after rats were treated(ig) with imperatorin, the plasma, urine, and feces were collected, and the samples were processed by solid phase extraction. Then, UHPLC-Q-Exactive Orbitrap MS was performed. In MS, 0.1% formic acid water(A)-acetonitrile(B) was applied as mobile phase for gradient elution and the data of MS in both positive and negative ion modes were collected. The metabolites of imperatorin in blood, urine, and feces of rats were analyzed to explore the metabolic pathways of imperatorin in rats. According to accurate molecular weight, multistage MS data, MS fragmentation rule of the standard substance, and previous reports, a total of 51 metabolites were identified, with 35, 40, and 16 from plasma, urine, and feces, separately. The main metabolic pathways were oxidization, glucuronidation, isopentenyl removal, sulphation, carboxylation, among others. The conclusion in this study is expected to serve as a reference for the further development and the further pharmacodynamics study of imperatorin.


Assuntos
Plasma , Extração em Fase Sólida , Animais , Cromatografia Líquida de Alta Pressão , Fezes , Furocumarinas , Ratos
5.
Zhongguo Zhong Yao Za Zhi ; 47(19): 5246-5255, 2022 Oct.
Artigo em Zh | MEDLINE | ID: mdl-36472031

RESUMO

The present study quickly identified the ginsenosides in fresh Panax ginseng and specified the effects of different drying methods(50 ℃-drying, 80 ℃-drying, and-70 ℃ freeze-drying) on ginsenosides.Three P.ginseng products by different drying methods were prepared, and the UHPLC-Q-Exactive Orbitrap high-resolution liquid mass spectrometry(MS) technique was applied to perform gradient elution using water-acetonitrile as the mobile phase, and the data collected in the negative ion mode were analyzed using X Calibur 2.2.The results showed that 57 saponins were identified from fresh P.ginseng.As revealed by the comparison with the fresh P.ginseng, in terms of the loss of ginsenosides, the dried products were ranked as the dried product at 50 ℃, freeze-dried products at-70 ℃, and the dried product at 80 ℃ in the ascending order.This study elucidated the effects of different drying methods on the types and relative content of ginsenosides, which can provide references for the processing of P.ginseng in the producing areas.


Assuntos
Ginsenosídeos , Panax , Saponinas , Ginsenosídeos/análise , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas/métodos
6.
Zhongguo Zhong Yao Za Zhi ; 47(4): 938-950, 2022 Feb.
Artigo em Zh | MEDLINE | ID: mdl-35285193

RESUMO

Ultra-performance liquid chromatography-quadrupole-electrostatic field Orbitrap mass spectrometry(UHPLC-Q-Exactive Orbitrap MS/MS) was used for rapid identification of the chemical components in Kaixin San substance benchmark. The gradient elution was performed through a Waters ACQUITY~(TM) BEH C_(18) column(2.1 mm×150 mm, 1.7 µm) with water-acetonitrile as mobile phase, a column temperature of 30 ℃, a flow rate of 0.3 mL·min~(-1), and a sample size of 1 µL. The scanning was performed in the negative ion mode. The complex component groups in Kaixin San substance benchmark were quickly and accurately identified and clearly assigned based on the comparison of the retention time and MS data with those of the reference substance as well as the relative molecular weight of the same or similar components in the mass spectrum database and literature. A total of 77 compounds were identified, including 26 saponins, 13 triterpenoid acids, 20 oligosaccharide esters, 5 xanthones, and 13 other compounds. The qualitative method established in this study can systematically, accurately, and quickly identify the chemical components in Kaixin San substance benchmark, which can provide a basis for the further analysis of its active components in vivo and the establishment of its quality control system.


Assuntos
Medicamentos de Ervas Chinesas , Espectrometria de Massas em Tandem , Benchmarking , Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas/química , Espectrometria de Massas em Tandem/métodos
7.
Neurobiol Dis ; 159: 105492, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34478849

RESUMO

Repulsive guidance molecule A (RGMa) is a potent inhibitor of axonal growth and a regulator of neuronal cell death. It is up-regulated following neuronal injury and accumulates in chronic neurodegenerative diseases. Neutralizing RGMa has the potential to promote neuroregeneration and neuroprotection. Previously we reported that a rat anti-N terminal RGMa (N-RGMa) antibody r5F9 and its humanized version h5F9 (ABT-207) promote neuroprotection and neuroregeneration in preclinical neurodegenerative disease models. However, due to its cross-reactivity to RGMc/hemojuvelin, ABT-207 causes iron accumulation in vivo, which could present a safety liability. Here we report the generation and characterization of a novel RGMa-selective anti-N-RGMa antibody elezanumab, which is currently under Phase 2 clinical evaluation in multiple disease indications. Elezanumab, a human monoclonal antibody generated by in vitro PROfusion mRNA display technology, competes with ABT-207 in binding to N-RGMa but lacks RGMc cross-reactivity with no impact on iron metabolism. It neutralizes repulsive activity of soluble RGMa in vitro and blocks membrane RGMa mediated BMP signaling. In the optic nerve crush and optic neuritis models, elezanumab promotes axonal regeneration and prevents retinal nerve fiber layer degeneration. In the spinal targeted experimental autoimmune encephalomyelitis (EAE) model, elezanumab promotes axonal regeneration and remyelination, decreases inflammatory lesion area and improves functional recovery. Finally, in the mouse cuprizone model, elezanumab reduces demyelination, which is consistent with its inhibitory effect on BMP signaling. Taken together, these preclinical data demonstrate that elezanumab has neuroregenerative and neuroprotective activities without impact on iron metabolism, thus providing a compelling rationale for its clinical development in neurodegenerative diseases.


Assuntos
Encefalomielite Autoimune Experimental , Proteínas Ligadas por GPI , Regeneração Nervosa , Proteínas do Tecido Nervoso , Neuroproteção , Traumatismos do Nervo Óptico , Nervo Óptico , Neurite Óptica , Recuperação de Função Fisiológica , Retina , Animais , Camundongos , Cuprizona/toxicidade , Encefalomielite Autoimune Experimental/induzido quimicamente , Encefalomielite Autoimune Experimental/fisiopatologia , Proteínas Ligadas por GPI/antagonistas & inibidores , Inibidores da Monoaminoxidase/toxicidade , Regeneração Nervosa/efeitos dos fármacos , Regeneração Nervosa/fisiologia , Proteínas do Tecido Nervoso/antagonistas & inibidores , Neuroproteção/efeitos dos fármacos , Nervo Óptico/efeitos dos fármacos , Nervo Óptico/fisiologia , Traumatismos do Nervo Óptico/fisiopatologia , Neurite Óptica/fisiopatologia , Recuperação de Função Fisiológica/efeitos dos fármacos , Recuperação de Função Fisiológica/fisiologia , Retina/efeitos dos fármacos , Ressonância de Plasmônio de Superfície
8.
Neurobiol Dis ; 155: 105385, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33991647

RESUMO

Spinal cord injury (SCI) is a devastating condition characterized by loss of function, secondary to damaged spinal neurons, disrupted axonal connections, and myelin loss. Spontaneous recovery is limited, and there are no approved pharmaceutical treatments to reduce ongoing damage or promote repair. Repulsive guidance molecule A (RGMa) is upregulated following injury to the central nervous system (CNS), where it is believed to induce neuronal apoptosis and inhibit axonal growth and remyelination. We evaluated elezanumab, a human anti-RGMa monoclonal antibody, in a novel, newly characterized non-human primate (NHP) hemicompression model of thoracic SCI. Systemic intravenous (IV) administration of elezanumab over 6 months was well tolerated and associated with significant improvements in locomotor function. Treatment of animals for 16 weeks with a continuous intrathecal infusion of elezanumab below the lesion was not efficacious. IV elezanumab improved microstructural integrity of extralesional tissue as reflected by higher fractional anisotropy and magnetization transfer ratios in treated vs. untreated animals. IV elezanumab also reduced SCI-induced increases in soluble RGMa in cerebrospinal fluid, and membrane bound RGMa rostral and caudal to the lesion. Anterograde tracing of the corticospinal tract (CST) from the contralesional motor cortex following 20 weeks of IV elezanumab revealed a significant increase in the density of CST fibers emerging from the ipsilesional CST into the medial/ventral gray matter. There was a significant sprouting of serotonergic (5-HT) fibers rostral to the injury and in the ventral horn of lower thoracic regions. These data demonstrate that 6 months of intermittent IV administration of elezanumab, beginning within 24 h after a thoracic SCI, promotes neuroprotection and neuroplasticity of key descending pathways involved in locomotion. These findings emphasize the mechanisms leading to improved recovery of neuromotor functions with elezanumab in acute SCI in NHPs.


Assuntos
Anticorpos Monoclonais/administração & dosagem , Proteínas Ligadas por GPI/antagonistas & inibidores , Proteínas do Tecido Nervoso/antagonistas & inibidores , Plasticidade Neuronal/efeitos dos fármacos , Neuroproteção/efeitos dos fármacos , Recuperação de Função Fisiológica/efeitos dos fármacos , Traumatismos da Medula Espinal/tratamento farmacológico , Sequência de Aminoácidos , Animais , Anticorpos Monoclonais/genética , Chlorocebus aethiops , Teste de Esforço/métodos , Humanos , Injeções Espinhais , Masculino , Plasticidade Neuronal/fisiologia , Neuroproteção/fisiologia , Primatas , Recuperação de Função Fisiológica/fisiologia , Traumatismos da Medula Espinal/patologia , Traumatismos da Medula Espinal/fisiopatologia , Vértebras Torácicas/lesões
9.
Neurobiol Dis ; 143: 104995, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32590037

RESUMO

Spinal cord injury (SCI) often results in permanent functional loss due to a series of degenerative events including cell death, axonal damage, and the upregulation of inhibitory proteins that impede regeneration. Repulsive Guidance Molecule A (RGMa) is a potent inhibitor of axonal growth that is rapidly upregulated following injury in both the rodent and human central nervous system (CNS). Previously, we showed that monoclonal antibodies that specifically block inhibitory RGMa signaling promote neuroprotective and regenerative effects when administered acutely in a clinically relevant rat model of thoracic SCI. However, it is unknown whether systemic administration of RGMa blocking antibodies are effective for SCI after delayed administration. Here, we administered elezanumab, a human monoclonal antibody targeting RGMa, intravenously either acutely or at 3 h or 24 h following thoracic clip impact-compression SCI. Rats treated with elezanumab acutely and at 3 h post-injury showed improvements in overground locomotion and fine motor function and gait. Rats treated 24 h post-SCI trended towards better recovery demonstrating significantly greater stride length and swing speed. Treated rats also showed greater tissue preservation with reduced lesion areas. As seen with acute treatment, delayed administration of elezanumab at 3 h post-SCI also increased perilesional neuronal sparing and serotonergic and corticospinal axonal plasticity. In addition, all elezanumab treated rats showed earlier spontaneous voiding ability and less post-trauma bladder wall hypertrophy. Together, our data demonstrate the therapeutic efficacy of delayed systemic administration of elezanumab in a rat model of SCI, and uncovers a new role for RGMa inhibition in bladder recovery following SCI.


Assuntos
Anticorpos Monoclonais/administração & dosagem , Proteínas Ligadas por GPI/antagonistas & inibidores , Proteínas de Membrana/antagonistas & inibidores , Proteínas do Tecido Nervoso/antagonistas & inibidores , Recuperação de Função Fisiológica/efeitos dos fármacos , Traumatismos da Medula Espinal/fisiopatologia , Animais , Feminino , Humanos , Ratos , Ratos Wistar , Micção/efeitos dos fármacos
10.
Crit Rev Toxicol ; 49(4): 342-356, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-31116061

RESUMO

Strains of the Bacillus cereus group have been widely used as probiotics for human beings, food animals, plants, and environmental remediation. Paradoxically, B. cereus is responsible for both gastrointestinal and nongastrointestinal syndromes and represents an important opportunistic food-borne pathogen. Toxicity assessment is a fundamental issue to evaluate safety of probiotics. Here, we summarize the state of our current knowledge about the toxins of B. cereus sensu lato to be considered for safety assessment of probiotic candidates. Surfactin-like emetic toxin (cereulide) and various enterotoxins including nonhemolytic enterotoxin, hemolysin BL, and cytotoxin K are responsible for food poisoning outbreaks characterized by emesis and diarrhea. In addition, other factors, such as hemolysin II, Certhrax, immune inhibitor A1, and sphingomyelinase, contribute to toxicity and overall virulence of B. cereus.


Assuntos
Bacillus cereus , Depsipeptídeos , Enterotoxinas , Doenças Transmitidas por Alimentos , Probióticos
11.
J Cell Sci ; 127(Pt 3): 641-52, 2014 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-24338367

RESUMO

Abnormal generation of inhibitory neurons that synthesize γ-aminobutyric acid (GABAergic) is characteristic of neuropsychological disorders. We provide evidence that the extracellular matrix molecule tenascin-R (TNR) - which is predominantly expressed by a subpopulation of interneurons - plays a role in the generation of GABAergic and granule neurons in the murine dentate gyrus by regulating fate determination of neural stem or progenitor cells (NSCs). During development, absence of TNR in constitutively TNR-deficient (TNR(-/-)) mice results in increased numbers of dentate gyrus GABAergic neurons, decreased expression of its receptor ß1 integrin, increased activation of p38 MAPK and increased expression of the GABAergic specification gene Ascl1. Postnatally, increased GABAergic input to adult hippocampal NSCs in TNR(-/-) mice is associated not only with increased numbers of GABAergic and, particularly, parvalbumin-immunoreactive neurons, as seen during development, but also with increased numbers of granule neurons, thus contributing to the increased differentiation of NSCs into granule cells. These findings indicate the importance of TNR in the regulation of hippocampal neurogenesis and suggest that TNR acts through distinct direct and indirect mechanisms during development and in the adult.


Assuntos
Proliferação de Células , Giro Denteado/crescimento & desenvolvimento , Neurogênese/genética , Tenascina/genética , Animais , Diferenciação Celular , Embrião de Mamíferos , Desenvolvimento Embrionário/genética , Matriz Extracelular/genética , Regulação da Expressão Gênica no Desenvolvimento , Hipocampo/metabolismo , Camundongos , Neurônios/metabolismo , Células-Tronco/metabolismo , Tenascina/metabolismo
12.
Biochem J ; 460(3): 437-46, 2014 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-24673421

RESUMO

Lack of permissive mechanisms and abundance of inhibitory molecules in the lesioned central nervous system of adult mammals contribute to the failure of functional recovery, which leads to severe disabilities in motor functions or pain. Previous studies have indicated that the neural cell adhesion molecule L1 constitutes a viable target to promote regeneration. In the present study, we describe the cloning, functional expression in Escherichia coli cells and purification of a recombinant αL1 Fab fragment that binds to L1 with comparable activity as the function-triggering monoclonal antibody 557.B6 and induces neurite outgrowth and neuronal survival in cultured neurons, despite its monovalent function. Infusion of αL1 Fab into the lesioned spinal cord of mice enhanced functional recovery after thoracic spinal cord compression injury. αL1 Fab treatment resulted in reduced scar volume, enhanced number of tyrosine hydroxylase-positive axons and increased linear density of VGLUT1 (vesicular glutamate transporter 1) on motoneurons. Furthermore, the number and soma size of ChAT (choline acetyltransferase)-positive motoneurons and the linear density of ChAT-positive boutons on motoneurons as well as parvalbumin-positive interneurons in the lumbar spinal cord were elevated. Stimulation of endogenous L1 by application of the αL1 Fab opens new avenues for recombinant antibody technology, offering prospects for therapeutic applications after traumatic nervous system lesions.


Assuntos
Fragmentos Fab das Imunoglobulinas/uso terapêutico , Molécula L1 de Adesão de Célula Nervosa/fisiologia , Recuperação de Função Fisiológica/fisiologia , Traumatismos da Medula Espinal/terapia , Animais , Anticorpos Monoclonais/uso terapêutico , Colina O-Acetiltransferase/biossíntese , Feminino , Camundongos , Camundongos Endogâmicos C57BL , Neurônios Motores/metabolismo , Regeneração Nervosa , Neuritos/fisiologia , Ratos , Proteínas Recombinantes/uso terapêutico , Traumatismos da Medula Espinal/fisiopatologia , Proteína Vesicular 1 de Transporte de Glutamato/biossíntese
13.
J Chromatogr A ; 1735: 465346, 2024 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-39243587

RESUMO

The Soret effect is a significant factor in various scenarios, with thermodiffusion in binary systems serving as a common method for the study. Most research focuses rarely on the distribution characteristics of components in diffusion systems; and Soret coefficients in the porous media could not be obtained by typical methods based on the thermodiffusion column, which are particularly important in the field of oil and gas development. Moreover, experiments on ground conditions have struggled to determine the Soret coefficient accurately due to the convective effect caused by gravity differentiation. The thermodiffusion behavior of n-pentane (C5) and n-heptane (C7) binary mixtures in both bulk and porous media conditions have been investigated, aiming to provide corrected coefficients that mitigate the influence of gravity using theoretical derivation. A new method was proposed to calculate the Soret coefficients in this work by establishing a model based on gas chromatography technology. Dynamic variation of component concentration along the path was studied, and the corresponding Soret coefficients were calculated and analyzed in parallel. The results indicate that the concentration and temperature exhibit a logarithmic relationship with the distance from the heat source. The Soret coefficient values obtained from measurements in porous media are closer to the theoretically corrected values, which do not account for gravity effects. Additionally, as the permeability decreases, the counteracting effect of porous media on convection becomes more pronounced. Therefore, it presents a novel method for accurately measuring the Soret coefficient that ignores convection to some extent.


Assuntos
Heptanos , Heptanos/química , Cromatografia Gasosa/métodos , Porosidade , Difusão , Hidrocarbonetos/química , Hidrocarbonetos/análise , Temperatura , Modelos Químicos , Pentanos
14.
Poult Sci ; 103(8): 103897, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38865770

RESUMO

Campylobacter jejuni continues to be a major public health issue worldwide. Poultry are recognized as the main reservoir for this foodborne pathogen. Implementing measures to decrease C. jejuni colonization on farms has been regarded as the most effective strategy to control the incidence of campylobacteriosis. The probiotics supplementation has been regarded as an attractive approach against C. jejuni in chickens. Here the inhibitory effects of one probiotic B. velezensis isolate CAU277 against C. jejuni was evaluated in vitro and in vivo. The in vitro antimicrobial activity showed that the supernatant of B. velezensis exhibited the most pronounced inhibitory effects on Campylobacter strains compared to other bacterial species. When co-cultured with B. velezensis, the growth of C. jejuni reduced significantly from 7.46 log10 CFU/mL (24 h) to 1.02 log10 CFU/mL (48 h). Further, the antimicrobial activity of B. velezensis against C. jejuni remained stable under a broad range of temperature, pH, and protease treatments. The in vivo experiments demonstrated that oral administration of B. velezensis significantly reduced the colonization of C. jejuni by 2.0 log10 CFU/g of feces in chicken cecum at 15 d postinoculation. In addition, the supplementary of B. velezensis significantly increased microbial species richness and diversity in chicken ileum, especially enhanced the bacterial population of Alistipes and Christensenellaceae, and decreased the existence of Lachnoclostridium. Our study presents that B. velezensis possesses antimicrobial activities against C. jejuni and promotes microbiota diversity in chicken intestines. These findings indicate a potential to develop an effective probiotic additive to control C. jejuni infection in chicken.


Assuntos
Bacillus , Infecções por Campylobacter , Campylobacter jejuni , Galinhas , Doenças das Aves Domésticas , Probióticos , Animais , Probióticos/farmacologia , Probióticos/administração & dosagem , Campylobacter jejuni/efeitos dos fármacos , Doenças das Aves Domésticas/prevenção & controle , Doenças das Aves Domésticas/microbiologia , Infecções por Campylobacter/veterinária , Infecções por Campylobacter/prevenção & controle , Infecções por Campylobacter/microbiologia , Bacillus/fisiologia , Ração Animal/análise , Dieta/veterinária , Microbioma Gastrointestinal/efeitos dos fármacos
15.
Front Cell Infect Microbiol ; 13: 1324760, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38268788

RESUMO

Introduction: Actinobacillus pleuropneumoniae, the causative agent of porcine pleuropneumonia, poses a significant threat to global swine populations due to its high prevalence, mortality rates, and substantial economic ramifications. Understanding the pathogen's defense mechanisms against host-produced reactive oxygen species is crucial for its survival, with OxyR, a conserved bacterial transcription factor, being pivotal in oxidative stress response. Methods: This study investigated the presence and role of OxyR in A. pleuropneumoniae serovar 1-12 reference strains. Transcriptomic analysis was conducted on an oxyR disruption mutant to delineate the biological activities influenced by OxyR. Additionally, specific assays were employed to assess urease activity, catalase expression, ApxI toxin secretion, as well as adhesion and invasion abilities of the oxyR disruption mutant on porcine 3D4/21 and PT cells. A mice challenge experiment was also conducted to evaluate the impact of oxyR inactivation on A. pleuropneumoniae virulence. Results: OxyR was identified as a conserved regulator present in A. pleuropneumoniae serovar 1-12 reference strains. Transcriptomic analysis revealed the involvement of OxyR in multiple biological activities. The oxyR disruption resulted in decreased urease activity, elevated catalase expression, enhanced ApxI toxin secretion-attributed to OxyR binding to the apxIBD promoter-and reduced adhesion and invasion abilities on porcine cells. Furthermore, inactivation of oxyR reduced the virulence of A. pleuropneumoniae in a mice challenge experiment. Discussion: The findings highlight the pivotal role of OxyR in influencing the virulence mechanisms of A. pleuropneumoniae. The observed effects on various biological activities underscore OxyR as an essential factor contributing to the pathogenicity of this bacterium.


Assuntos
Actinobacillus pleuropneumoniae , Animais , Camundongos , Suínos , Actinobacillus pleuropneumoniae/genética , Catalase/genética , Virulência , Urease , Estresse Oxidativo
16.
Vet Microbiol ; 277: 109631, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36543091

RESUMO

Campylobacter jejuni is considered as the leading cause of worldwide foodborne bacterial gastroenteritis. Chicken is the main reservoir of C. jejuni. Avian innate immune responses to C. jejuni remain poorly defined. Chicken host defense peptides (HDPs) are the major components of avian innate immune system. This study aimed to characterize the chicken HDPs responses to C. jejuni in vitro and in vivo. In the HD11 macrophage cell line, the HDPs, including AvBD1-2, CATH1-3, AvBD7, AvBD4, and AvBD6, were relatively higher expressed in untreated cells, whereas the expressions were suppressed after C. jejuni infection. In contrast, C. jejuni infection significantly increased the expression of the lower expressed HDPs, such as AvBD3, AvBD5, AvBD8-14, and CATHB1, in untreated cells. In the chicken challenge experiment, the immune tissues of spleens and cecal tonsils were collected from C. jejuni-infected and uninfected chickens at 1, 3 and 15 day post inoculation (DPI). In spleens of C. jejuni-infected chickens, only AvBD14 expression was elevated at 1 DPI. The majority of avian HDPs were significantly up-regulated at 3 DPI and dramatically decreased to the levels of uninfected controls at 15 DPI. In chicken cecal tonsils, only AvBD9 and AvBD14 were significantly up-regulated at 1 DPI with C. jejuni infection. Collectively, C. jejuni infection induced dynamic expression of chicken HDPs in both macrophage HD11 and immune tissues of chickens. Suppression of chicken HDPs expression may be an evasion strategy of C. jejuni for persistent colonization in chicken intestine by circumventing the chicken immune system.


Assuntos
Infecções por Campylobacter , Campylobacter jejuni , Gastroenterite , Doenças das Aves Domésticas , Animais , Galinhas/microbiologia , Peptídeos Catiônicos Antimicrobianos , Intestinos , Imunidade Inata , Gastroenterite/veterinária , Infecções por Campylobacter/veterinária , Infecções por Campylobacter/microbiologia , Doenças das Aves Domésticas/microbiologia
17.
Vet Sci ; 10(12)2023 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-38133250

RESUMO

Subclinical mastitis is a common disease that threatens the welfare and health of dairy cows and causes huge economic losses. Somatic cell count (SCC) is the most suitable indirect index used to evaluate the degree of mastitis. To explore the relationship between SCC, diversity in the microbiome, and subclinical mastitis, we performed next-generation sequencing of the 16S rRNA gene of cow's milk with different SCC ranges. The data obtained showed that the microbiota was rich and coordinated with SCC below 2 × 105. SCC above 2 × 105 showed a decrease in the diversity of microbial genera. When SCC was below 2 × 105, the phylum Actinobacteriota accounted for the most. When SCC was between 2 × 105 and 5 × 105, Firmicutes accounted for the most, and when SCC exceeded 5 × 105, Firmicutes and Proteobacteria accounted for the most. Pathogenic genera such as Streptococcus spp. were absent, while SCC above 2 × 105 showed a decrease in the diversity of microbial genera. SCC was positively correlated with the percentage of Romboutsia, Turicibacter, and Paeniclostridium and negatively correlated with the percentage of Staphylococcus, Psychrobacter, Aerococcus, and Streptococcus. Romboutsia decreased 6.19 times after the SCC exceeded 2 × 105; the SCC increased exponentially from 2 × 105 to 5 × 105 and above 1 × 106 in Psychrobacter. Analysis of the microbiota of the different SCC ranges suggests that the development of mastitis may not only be a primary infection but may also be the result of dysbiosis in the mammary gland.

18.
Front Pharmacol ; 13: 948939, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35935868

RESUMO

Hyperuricemia (HUA) is a common metabolic disease that is an independent risk factor for comorbidities such as hypertension, chronic kidney disease, and coronary artery disease. The prevalence of HUA has increased over the last several decades with improved living standards and increased lifespans. Metabolites are considered the most direct reflection of individual physiological and pathological conditions, and represent attractive candidates to provide deep insights into disease phenotypes. Metabolomics, a technique used to profile metabolites in biofluids and tissues, is a powerful tool for identification of novel biomarkers, and can be used to provide valuable insights into the etiopathogenesis of metabolic diseases and to evaluate the efficacy of drugs. In this study, multi metabolomics-based analysis of the blood, urine, and feces of rats with HUA showed that HUA significantly altered metabolite profiles. Astragalus membranaceus (AM) and benbromomalone significantly mitigated these changes in blood and feces, but not in urine. Some crucial metabolic pathways including lipid metabolism, lipid signaling, hormones synthesis, unsaturated fatty acid (UFAs) absorption, and tryptophan metabolism, were seriously disrupted in HUA rats. In addition, AM administration exerted better treatment effects on HUA than benbromomalone. Furthermore, additional supplementation with UFAs and tryptophan may also induce therapeutic effects against HUA.

19.
Front Optoelectron ; 15(1): 31, 2022 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-36637672

RESUMO

In this paper, we present an edge detection scheme based on ghost imaging (GI) with a holistically-nested neural network. The so-called holistically-nested edge detection (HED) network is adopted to combine the fully convolutional neural network (CNN) with deep supervision to learn image edges effectively. Simulated data are used to train the HED network, and the unknown object's edge information is reconstructed from the experimental data. The experiment results show that, when the compression ratio (CR) is 12.5%, this scheme can obtain a high-quality edge information with a sub-Nyquist sampling ratio and has a better performance than those using speckle-shifting GI (SSGI), compressed ghost edge imaging (CGEI) and subpixel-shifted GI (SPSGI). Indeed, the proposed scheme can have a good signal-to-noise ratio performance even if the sub-Nyquist sampling ratio is greater than 5.45%. Since the HED network is trained by numerical simulations before the experiment, this proposed method provides a promising way for achieving edge detection with small measurement times and low time cost.

20.
Food Chem ; 391: 133241, 2022 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-35598389

RESUMO

Enterobactin (Ent) is a promising indicator to monitor intestinal level of Enterobacteriaceae for assessment of gut inflammation. In this study, we developed a monoclonal antibody (mAb)-based ELISA for Ent quantification. We immunized mice with an Ent conjugate vaccine. An mAb named 2E4, with the highest anti-Ent antibody titer, was selected for developing indirect competitive ELISA (ic-ELISA). The purified mAb 2E4 showed high affinity (3.1 × 10-10 M) and specificity to Ent. The limit of detection of ic-ELISA was 0.39 µg/mL. The intra- and inter-assay recovery rates of standard curve were up to 94.6% with the coefficients of variation between 4.0% and 12.3%, indicating high accuracy, repeatability, and reproducibility of the ic-ELISA. In addition, the ic-ELISA was able to quantitatively detect Ent produced in different bacterial cultures. Collectively, this study developed an ic-ELISA with excellent performance in Ent quantification, laying a solid foundation for Ent-based diagnostics of gut health.


Assuntos
Enterobactina , Sideróforos , Animais , Anticorpos Monoclonais , Enterobacteriaceae , Ensaio de Imunoadsorção Enzimática , Camundongos , Camundongos Endogâmicos BALB C , Reprodutibilidade dos Testes
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