Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 8 de 8
Filtrar
Mais filtros

Base de dados
Tipo de documento
País de afiliação
Intervalo de ano de publicação
1.
PLoS Pathog ; 18(6): e1010620, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35696443

RESUMO

Intestinal microbial metabolites have been increasingly recognized as important regulators of enteric viral infection. However, very little information is available about which specific microbiota-derived metabolites are crucial for swine enteric coronavirus (SECoV) infection in vivo. Using swine acute diarrhea syndrome (SADS)-CoV as a model, we were able to identify a greatly altered bile acid (BA) profile in the small intestine of infected piglets by untargeted metabolomic analysis. Using a newly established ex vivo model-the stem cell-derived porcine intestinal enteroid (PIE) culture-we demonstrated that certain BAs, cholic acid (CA) in particular, enhance SADS-CoV replication by acting on PIEs at the early phase of infection. We ruled out the possibility that CA exerts an augmenting effect on viral replication through classic farnesoid X receptor or Takeda G protein-coupled receptor 5 signaling, innate immune suppression or viral attachment. BA induced multiple cellular responses including rapid changes in caveolae-mediated endocytosis, endosomal acidification and dynamics of the endosomal/lysosomal system that are critical for SADS-CoV replication. Thus, our findings shed light on how SECoVs exploit microbiome-derived metabolite BAs to swiftly establish viral infection and accelerate replication within the intestinal microenvironment.


Assuntos
Alphacoronavirus , Infecções por Coronavirus , Doenças dos Suínos , Alphacoronavirus/fisiologia , Animais , Ácidos e Sais Biliares , Cavéolas , Diarreia , Suínos
2.
J Nat Prod ; 86(8): 1910-1918, 2023 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-37530709

RESUMO

Four new δ- and γ-lactone derivatives, hyperelatolides A-D (1-4, respectively), were discovered from the aerial portions of Hypericum elatoides R. Keller. Their structures were elucidated by analysis of NMR spectra, HRESIMS, quantum chemical calculations of NMR and ECD spectra, and X-ray crystallographic data. Hyperelatolides A (1) and B (2) represent the first examples of δ-lactone derivatives characterized by a (Z)-(5,5-dimethyl-2-(2-oxopropyl)cyclohexylidene)methyl moiety and a benzoyloxy group attached to the ß- and γ-positions of the δ-lactone core, respectively, while hyperelatolides C (3) and D (4) are unprecedented γ-lactone derivatives featuring substituents similar to those of 1 and 2. All compounds were tested for their inhibitory effects on NO production in LPS-activated BV-2 cells. Lactones 1 and 2 exhibited considerable antineuroinflammatory activity, with IC50 values of 5.74 ± 0.27 and 7.35 ± 0.26 µM, respectively. Moreover, the mechanistic study revealed that lactone 1 significantly suppressed nuclear factor kappa B signaling and downregulated the expression of inducible nitric oxide synthase and cyclooxygenase-2 in LPS-induced cells, which may contribute to its antineuroinflammatory activity.


Assuntos
Hypericum , Hypericum/química , Lipopolissacarídeos/farmacologia , Espectroscopia de Ressonância Magnética , Lactonas/farmacologia , Lactonas/química , Transdução de Sinais , Estrutura Molecular , Óxido Nítrico
3.
J Nat Prod ; 86(1): 119-130, 2023 01 27.
Artigo em Inglês | MEDLINE | ID: mdl-36579935

RESUMO

Nine new sesquiterpenes, hyperhubeins A-I (1-9), and 14 known analogues (10-23) were isolated from the aerial portions of Hypericum hubeiense. Their structures and absolute configurations were determined unambiguously via spectroscopic analysis, single-crystal X-ray diffraction, and electronic circular dichroism calculations. Compounds 1-3 possess an unprecedented sesquiterpene carbon skeleton. Further, a plausible biosynthetic pathway from farnesyl diphosphate (FPP) is proposed. The isolated phytochemicals were evaluated for neuroprotective and anti-neuroinflammatory properties in vitro. Compounds 1, 2, 5-8, 14, and 21 displayed notable neuroprotective activity against hydrogen peroxide (H2O2)-induced lesions in PC-12 cells at 10 µM. Additionally, compounds 1, 2, 12, and 13 exhibited inhibition of lipopolysaccharide (LPS)-induced nitric oxide (NO) production in BV-2 microglial cells, with their IC50 values ranging from 4.92 to 6.81 µM. Possible interactions between these bioactive compounds and inducible nitric oxide synthase (iNOS) were predicted via molecular docking. Moreover, Western blotting indicated that compound 12 exerted anti-neuroinflammatory activity by suppressing LPS-stimulated expression of toll-like receptor-4 (TLR-4) and inhibiting consequent activation of nuclear factor-kappa-B (NF-κB) signaling.


Assuntos
Hypericum , Sesquiterpenos , Anti-Inflamatórios/química , Lipopolissacarídeos/farmacologia , Lipopolissacarídeos/metabolismo , Peróxido de Hidrogênio , Simulação de Acoplamento Molecular , NF-kappa B/metabolismo , Microglia/metabolismo , Dicroísmo Circular , Óxido Nítrico , Óxido Nítrico Sintase Tipo II/metabolismo
4.
J Asian Nat Prod Res ; 16(11): 1074-83, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25082563

RESUMO

Adiponectin, an adipokine with insulin-sensitizing effect, is secreted from adipocytes into circulation as high, medium, and low molecular weight (HMW, MMW, and LMW) forms. The HMW adiponectin is more metabolically active and the ratio of HMW adiponectin to total adiponectin directly correlates with insulin sensitivity. Evodiamine is an indole alkaloid found in the traditional Chinese medicinal plant Evodia rutaecarpa. In this study, evodiamine was found to activate AMP-activated protein kinase (AMPK) in both 3T3-L1 adipocytes and 293T cells. Activation of AMPK by evodiamine promoted the assembly of HMW adiponectin and increased the HMW/total ratio of adiponectin in 3T3-L1 adipocytes. The Ca(2+)-dependent PI3K/Akt/CaMKII-signaling pathway was demonstrated to be involved in evodiamine-induced AMPK activation. This study revealed a novel role of this Ca(2+)-mediated signaling pathway in promoting the multimerization of adiponectin.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Adiponectina/metabolismo , Evodia/química , Quinazolinas/farmacologia , Células 3T3-L1 , Adipócitos/metabolismo , Animais , Cálcio/metabolismo , Resistência à Insulina , Camundongos , Estrutura Molecular , Peso Molecular , Fosfatidilinositol 3-Quinases/metabolismo , Transdução de Sinais/efeitos dos fármacos
5.
Commun Chem ; 7(1): 1, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38167859

RESUMO

The search for lead compounds with anti-neuroinflammatory activity from structurally 'optimized' natural products is a crucial and promising strategy in the quest to discover safe and efficacious agents for treating neurodegenerative diseases. A phytochemical investigation on the aerial portions of Hypericum elatoides led to the isolation of five nitrogenous polycyclic polyprenylated acylphloroglucinols (PPAPs), hyperelanitriles A-D (1-4) and hyperelamine A (5). Their structures were determined by spectroscopic analysis, ECD and NMR calculations, and X-ray crystallography. To the best of our knowledge, compounds 1-4 represent the first examples of acylphloroglucinols featuring an α-aminonitrile moiety, while 5 is a rare enamine-containing PPAP. Further, the synthesis of these naturally occurring PPAP-based nitriles or amines was accomplished. Compound 5 exhibited inhibitory activity against LPS-activated NO production in BV-2 cells, potentially through the suppression of TLR-4/NF-κB signaling. Here we show the isolation, structural elucidation, synthesis, and bioactive evaluation of compounds 1-5.

6.
Yi Chuan ; 34(2): 198-207, 2012 Feb.
Artigo em Zh | MEDLINE | ID: mdl-22382061

RESUMO

Diabetic neuropathy (DN) is defined as the presence of symptoms and/or signs of peripheral nerve dysfunction in people with diabetes. The aim of this study is to screen differentially expressed genes in peripheral ganglia in early stage type Ⅱ experimental diabetic rats. We compared gene expression profiles of peripheral ganglia in type Ⅱ diabetic and nondiabetic rats based on Illumina® Sentrix® BeadChip arrays. The results showed that 158 out of a total of 12 604 known genes were significantly differentially expressed, including 87 up-regulated and 71 down-regulated genes, in diabetic rats compared with those in the nondiabetic rats. It is noted that some up-regulated genes are involved in the biological processes of neuronal cytoskeleton and motor proteins. In contrast, the down-regulated genes are associated with the response to virus\biotic stimulus\ other organism in diabetic rats. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis revealed that the most significant pathway enriched in the changed gene set is metabolism (P < 0.001). These results indicated that metabolic changes in peripheral ganglia of diabetic rats could be induced by hyperglycemia. Hyperglycemia could change the expression of genes involved in neuronal cytoskeleton and motor proteins through immune inflammatory response, and then impair the structure and function of the peripheral ganglia.


Assuntos
Diabetes Mellitus Tipo 2/metabolismo , Neuropatias Diabéticas/metabolismo , Gânglios/metabolismo , Perfilação da Expressão Gênica , Animais , Masculino , Ratos , Ratos Sprague-Dawley
7.
Nat Prod Res ; 36(14): 3520-3528, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33356581

RESUMO

Plants of the genus Hypericum contain various types of secondary metabolites that exhibited extensive biological activities. In the ongoing efforts to discover natural neuroinflammatory inhibitors with the potential to develop into therapeutic agents for neurodegenerative diseases, two new benzophenone glycosides, hyperewalones A and B (1 and 2), along with eight known compounds (3-10), were isolated from the aerial parts of Hypericum przewalskii. Their structures were elucidated by comprehensive analysis of IR, HRESIMS, 1D and 2D NMR spectra, and chemical derivatization. The anti-neuroinflammatory activity of compounds 1-10 was evaluated by determining their ability to inhibit the production of nitric oxide (NO) in lipopolysaccharide (LPS)-activated BV-2 microglial cells. Compounds 2, 4, 6-8 exhibited significant anti-neuroinflammatory activity with IC50 values of 0.61-4.90 µM. These findings suggest that the benzophenone, ionone, and flavonoid glycosides isolated from H. przewalskii are promising anti-neuroinflammatory compounds worthy of further investigations.


Assuntos
Hypericum , Benzofenonas/química , Benzofenonas/farmacologia , Glicosídeos/química , Hypericum/química , Estrutura Molecular , Óxido Nítrico , Componentes Aéreos da Planta/química
8.
mBio ; 12(3)2021 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-33975932

RESUMO

Intestinal microbiomes are of vital importance in antagonizing systemic viral infection. However, very little literature has shown whether commensal bacteria play a crucial role in protecting against enteric virus systemic infection from the aspect of modulating host innate immunity. In the present study, we utilized an enteric virus, encephalomyocarditis virus (EMCV), to inoculate mice treated with phosphate-buffered saline (PBS) or given an antibiotic cocktail (Abx) orally or intraperitoneally to examine the impact of microbiota depletion on virulence and viral replication in vivo Microbiota depletion exacerbated the mortality, neuropathogenesis, viremia, and viral burden in brains following EMCV infection. Furthermore, Abx-treated mice exhibited severely diminished mononuclear phagocyte activation and impaired type I interferon (IFN) production and expression of IFN-stimulated genes (ISG) in peripheral blood mononuclear cells (PBMC), spleens, and brains. With the help of fecal bacterial 16S rRNA sequencing of PBS- and Abx-treated mice, we identified a single commensal bacterium, Blautia coccoides, that can restore mononuclear phagocyte- and IFNAR (IFN-α/ß receptor)-dependent type I IFN responses to restrict systemic enteric virus infection. These findings may provide insight into the development of novel therapeutics for preventing enteric virus infection or possibly alleviating clinical diseases by activating host systemic innate immune responses via respective probiotic treatment using B. coccoidesIMPORTANCE While cumulative data indicate that indigenous commensal bacteria can facilitate enteric virus infection, little is known regarding whether intestinal microbes have a protective role in antagonizing enteric systemic infection by modulating host innate immunity. Although accumulating literature has pointed out that the microbiota has a fundamental impact on host systemic antiviral innate immune responses mediated by type I interferon (IFN), only a few specific commensal bacteria species have been revealed to be capable of regulating IFN-I and ISG expression, not to mention the underlying mechanisms. Thus, it is important to understand the cross talk between microbiota and host anti-enteric virus innate immune responses and characterize the specific bacterial species that possess protective functions. Our study demonstrates how fundamental innate immune mediators such as mononuclear phagocytes and type I IFN are regulated by commensal bacteria to antagonize enteric virus systemic infection. In particular, we have identified a novel commensal bacterium, Blautia coccoides, that can restrict enteric virus replication and neuropathogenesis by activating IFN-I and ISG responses in mononuclear phagocytes via an IFNAR- and STAT1-mediated signaling pathway.


Assuntos
Infecções por Cardiovirus/prevenção & controle , Vírus da Encefalomiocardite/imunologia , Microbioma Gastrointestinal/imunologia , Imunidade Inata , Interferon Tipo I/imunologia , Viremia/imunologia , Viremia/prevenção & controle , Animais , Antibacterianos/administração & dosagem , Infecções por Cardiovirus/imunologia , Clostridiales/imunologia , Vírus da Encefalomiocardite/patogenicidade , Feminino , Microbioma Gastrointestinal/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Transdução de Sinais , Simbiose/imunologia , Replicação Viral/imunologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA