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1.
Nat Commun ; 15(1): 2983, 2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38582860

RESUMO

Akkermansia muciniphila has received great attention because of its beneficial roles in gut health by regulating gut immunity, promoting intestinal epithelial development, and improving barrier integrity. However, A. muciniphila-derived functional molecules regulating gut health are not well understood. Microbiome-secreted proteins act as key arbitrators of host-microbiome crosstalk through interactions with host cells in the gut and are important for understanding host-microbiome relationships. Herein, we report the biological function of Amuc_1409, a previously uncharacterised A. muciniphila-secreted protein. Amuc_1409 increased intestinal stem cell (ISC) proliferation and regeneration in ex vivo intestinal organoids and in vivo models of radiation- or chemotherapeutic drug-induced intestinal injury and natural aging with male mice. Mechanistically, Amuc_1409 promoted E-cadherin/ß-catenin complex dissociation via interaction with E-cadherin, resulting in the activation of Wnt/ß-catenin signaling. Our results demonstrate that Amuc_1409 plays a crucial role in intestinal homeostasis by regulating ISC activity in an E-cadherin-dependent manner and is a promising biomolecule for improving and maintaining gut health.


Assuntos
Verrucomicrobia , beta Catenina , Masculino , Camundongos , Animais , beta Catenina/metabolismo , Verrucomicrobia/metabolismo , Intestinos , Caderinas/metabolismo , Akkermansia
2.
Int J Mol Sci ; 23(22)2022 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-36430486

RESUMO

Fulminant hepatitis is characterized by rapid and massive immune-mediated liver injury. Dosage-sensitive sex reversal-adrenal hypoplasia congenita critical region on the X chromosome, gene 1 (DAX1; NR0B1) represses the transcription of various genes. Here, we determine whether DAX1 serves as a regulator of inflammatory liver injury induced by concanavalin A (ConA). C57BL/6J (WT), myeloid cell-specific Dax1 knockout (MKO), and hepatocyte-specific Dax1 knockout (LKO) mice received single intravenous administration of ConA. Histopathological changes in liver and plasma alanine aminotransferase and aspartate aminotransferase levels in Dax1 MKO mice were comparable with those in WT mice following ConA administration. Unlike Dax1 MKO mice, Dax1 LKO mice were greatly susceptible to ConA-induced liver injury, which was accompanied by enhanced infiltration of immune cells, particularly CD4+ and CD8+ T cells, in the liver. Factors related to T-cell recruitment, including chemokines and adhesion molecules, significantly increased following enhanced and prolonged phosphorylation of NF-κB p65 in the liver of ConA-administered Dax1 LKO mice. This is the first study to demonstrate that hepatocyte-specific DAX1 deficiency exacerbates inflammatory liver injury via NF-κB p65 activation, thereby causing T-cell infiltration by modulating inflammatory chemokines and adhesion molecules. Our results suggest DAX1 as a therapeutic target for fulminant hepatitis treatment.


Assuntos
Linfócitos T CD8-Positivos , Necrose Hepática Massiva , Camundongos , Animais , NF-kappa B , Camundongos Endogâmicos C57BL , Hepatócitos , Transdução de Sinais , Concanavalina A/toxicidade , Linfócitos T CD4-Positivos
3.
Int J Mol Sci ; 23(19)2022 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-36233086

RESUMO

Acetaminophen (APAP) is a widely used analgesic and antipyretic drug, but its overdose can cause acute liver failure. The dosage-sensitive sex reversal adrenal hypoplasia congenita critical region on the X chromosome, gene 1 (DAX-1, NR0B1), is an orphan nuclear receptor that acts as a transcriptional co-repressor of various genes. In this study, we identified the role of DAX-1 in APAP-induced liver injury using hepatocyte-specific Dax-1 knockout (Dax-1 LKO) mice. Mouse primary hepatocytes were used as a comparative in vitro study. APAP overdose led to decreased plasma alanine aminotransferase and aspartate aminotransferase levels in Dax-1 LKO mice compared to C57BL/6J (WT) controls, accompanied by reduced liver necrosis. The expression of the genes encoding the enzymes catalyzing glutathione (GSH) synthesis and metabolism and antioxidant enzymes was increased in the livers of APAP-treated Dax-1 LKO mice. The rapid recovery of GSH levels in the mitochondrial fraction of APAP-treated Dax-1 LKO mice led to reduced reactive oxygen species levels, resulting in the inhibition of the prolonged JNK activation. The hepatocyte-specific DAX-1 deficiency increased the protein expression of nuclear factor erythroid 2-related factor 2 (Nrf2) compared with WT controls after APAP administration. These results indicate that DAX-1 deficiency in hepatocytes protects against APAP-induced liver injury by Nrf2-regulated antioxidant defense.


Assuntos
Antipiréticos , Doença Hepática Induzida por Substâncias e Drogas , Receptor Nuclear Órfão DAX-1 , Fator 2 Relacionado a NF-E2 , Acetaminofen/toxicidade , Alanina Transaminase/metabolismo , Animais , Antioxidantes/metabolismo , Aspartato Aminotransferases/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/genética , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Proteínas Correpressoras/metabolismo , Receptor Nuclear Órfão DAX-1/genética , Glutationa/metabolismo , Hepatócitos/metabolismo , Fígado/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Receptores Nucleares Órfãos/metabolismo , Espécies Reativas de Oxigênio/metabolismo
4.
Lab Anim Res ; 38(1): 21, 2022 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-35854340

RESUMO

BACKGROUND: Neuroinflammation plays an important role in cognitive decline and memory impairment in neurodegenerative disorders. Previously, we demonstrated that Humulus japonicus (HJ) has anti-inflammatory effects in rodent models of Alzheimer's disease and Parkinson's disease. The present study aimed to examine the protective potential of HJ extracts against lipopolysaccharide (LPS)-induced cognitive impairment and scopolamine-induced amnesia in mouse models. Cognitive improvement of mice was investigated by novel object recognition test. For analyzing effects on neuroinflammation, immunohistochemistry and quantitative real-time polymerase chain reaction (qRT-PCR) assays were performed. RESULTS: We found that the oral administration of HJ significantly improved cognitive dysfunction induced by LPS in a novel object recognition test. The LPS-induced activation of microglia was notably decreased by HJ treatment in the cortex and hippocampus. HJ administration with LPS also significantly increased the mRNA expression of interleukin (IL)-10 and decreased the mRNA expression of IL-12 in the parietal cortex of mice. The increased expression of LPS-induced complement C1q B chain (C1bq) and triggering receptor expressed on myeloid cells 2 (Trem2) genes was significantly suppressed by HJ treatment. In addition, HJ administration significantly improved novel object recognition in a scopolamine-induced amnesia mouse model. CONCLUSIONS: These findings revealed that HJ has a beneficial effect on cognitive impairment and neuroinflammation induced by systemic inflammation and on amnesia induced by scopolamine in mice.

5.
Nutr Res ; 86: 96-108, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33551257

RESUMO

Alzheimer's disease (AD) is the most prevalent neurodegenerative disease, and is characterized by the accumulation and presence of amyloid plaques (Aß), tangles, dementia, and cognitive impairment. Currently, there is no known cure for AD; however, recently, the association between alteration of the gut microbiota and AD pathology has been explored to find novel therapeutic approaches. Microbiota-targeted intervention has been suggested as an attractive therapeutic approach for AD. Agathobaculum butyriciproducens (SR79) is a strict anaerobic and butyric acid-producing bacteria. We hypothesized that administration of SR79 might have a beneficial effect on cognitive deficits and AD pathologies. To determine the therapeutic effects of SR79 on AD pathologies, APP/PS1 transgenic and lipopolysaccharide -induced cognitive impairment mouse models were used. In the lipopolysaccharide -induced cognitive deficit model, the administration of SR79 improved cognitive function and decreased microglia activation. In addition, the administration of SR79 to APP/PS1 mice significantly improved novel object recognition and percent alteration results in novel object recognition and Y-maze alteration tests. Furthermore, Aß plaque deposition and microglial activation were markedly reduced in the parietal cortex and hippocampus after SR79 treatment in APP/PS1 mice. SR79 treatment significantly decreased gene expression levels of IL-1ß and C1QB and increased the gene expression levels of IGF-1 and thereby the downstream signaling pathway in the cortex of APP/PS1 mice. In conclusion, SR79 administration improved cognitive function and AD pathologies through the regulation of neuroinflammation and IGF-1 signaling in an animal model.


Assuntos
Doença de Alzheimer/terapia , Clostridiales/fisiologia , Cognição , Disfunção Cognitiva/terapia , Microbioma Gastrointestinal/fisiologia , Probióticos , Doença de Alzheimer/microbiologia , Peptídeos beta-Amiloides/metabolismo , Animais , Encéfalo/patologia , Encéfalo/fisiopatologia , Modelos Animais de Doenças , Humanos , Fator de Crescimento Insulin-Like I/genética , Fator de Crescimento Insulin-Like I/metabolismo , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Lipopolissacarídeos , Aprendizagem em Labirinto , Camundongos , Camundongos Transgênicos , Microglia/fisiologia , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismo , Placa Amiloide/terapia , Reconhecimento Psicológico
6.
Mol Med Rep ; 23(3)2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33495840

RESUMO

The dopamine precursor 3,4­dihydroxyphenyl­ l­alanine (L­DOPA) is the most widely used symptomatic treatment for Parkinson's disease (PD); however, its prolonged use is associated with L­DOPA­induced dyskinesia in more than half of patients after 10 years of treatment. The present study investigated whether co­treatment with ß­Lapachone, a natural compound, and L­DOPA has protective effects in a 6­hydroxydopamine (6­OHDA)­induced mouse model of PD. Unilateral 6­OHDA­lesioned mice were treated with vehicle or ß­Lapachone (10 mg/kg/day) and L­DOPA for 11 days. Abnormal involuntary movements (AIMs) were scored on days 5 and 10. ß­Lapachone (10 mg/kg) co­treatment with L­DOPA decreased the AIMs score on both days 5 and 10. ß­Lapachone was demonstrated to have a beneficial effect on the axial and limb AIMs scores on day 10. There was no significant suppression in dopamine D1 receptor­related and ERK1/2 signaling in the DA­denervated striatum by ß­Lapachone­cotreatment with L­DOPA. Notably, ß­Lapachone­cotreatment with L­DOPA increased phosphorylation at the Ser9 site of glycogen synthase kinase 3ß (GSK­3ß), indicating suppression of GSK­3ß activity in both the unlesioned and 6­OHDA­lesioned striata. In addition, astrocyte activation was markedly suppressed by ß­Lapachone­cotreatment with L­DOPA in the striatum and substantia nigra of the unilateral 6­OHDA model. These findings suggest that ß­Lapachone cotreatment with L­DOPA therapy may have therapeutic potential for the suppression or management of the development of L­DOPA­induced dyskinesia in patients with PD.


Assuntos
Discinesias , Levodopa/efeitos adversos , Naftoquinonas/farmacologia , Oxidopamina/efeitos adversos , Doença de Parkinson Secundária , Animais , Discinesias/tratamento farmacológico , Discinesias/metabolismo , Discinesias/patologia , Levodopa/farmacologia , Masculino , Camundongos , Oxidopamina/farmacologia , Doença de Parkinson Secundária/induzido quimicamente , Doença de Parkinson Secundária/tratamento farmacológico , Doença de Parkinson Secundária/metabolismo , Doença de Parkinson Secundária/patologia
7.
Int J Mol Med ; 45(2): 417-428, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31894253

RESUMO

Humulus japonicus (HJ) is a widely used herbal medicine in Asia with anti­oxidative, anti­microbial, and anti­inflammatory effects. We investigated the potential therapeutic effects of HJ in rheumatoid arthritis (RA) using a mouse model of collagen­induced arthritis (CIA) and a lipopolysaccharide­stimulated murine macrophage cell line (RAW 264.7). The CIA mice were administered 300 mg/kg HJ orally starting 3 days prior to second immunization. The clinical and histopathological findings were assessed in the paw of CIA mice. The levels of autoantibodies and inflammatory markers were determined in the plasma and cell culture supernatant, respectively. The expression at mRNA and protein levels was analyzed by reverse transcription quantitative­PCR and western blot analysis, respectively. HJ significantly decreased the gross arthritic scores and paw swelling in CIA mice. Furthermore, synovial inflammation, cartilage destruction, and bone erosion were markedly reduced by HJ. It also decreased the expression of inflammatory enzymes in both the paw of mice and RAW 264.7 cells. Moreover, the expression of genes related to all macrophages and pro­inflammatory M1 macrophage were significantly decreased, whereas the expression of anti­inflammatory M2 macrophage marker was markedly increased in the paw of HJ­treated CIA mice. In addition, HJ suppressed the levels of plasma anti­type II collagen antibody following the decreased expression of T helper type 1 (Th1) and Th2 cell­associated surface markers and cytokines in the paw. HJ also significantly inhibited the expression of IL­6 both in vitro and in vivo, followed by reduced STAT3 phosphorylation and expression in the paw of CIA mice. Finally, the expression of osteoclast­related genes was decreased in the paw of HJ­treated CIA mice. These findings suggest that HJ can play a role in suppressing the development of CIA by overall regulation of articular inflammation. This study should provide new insights into the use of HJ as a therapeutically effective natural product against RA.


Assuntos
Anti-Inflamatórios/uso terapêutico , Artrite Experimental/tratamento farmacológico , Artrite Reumatoide/tratamento farmacológico , Humulus , Extratos Vegetais/uso terapêutico , Animais , Anti-Inflamatórios/química , Artrite Experimental/imunologia , Artrite Reumatoide/imunologia , Autoanticorpos/imunologia , Modelos Animais de Doenças , Humulus/química , Inflamação/tratamento farmacológico , Inflamação/imunologia , Mediadores da Inflamação/imunologia , Masculino , Camundongos , Extratos Vegetais/química , Células RAW 264.7
8.
Arch Toxicol ; 94(2): 509-522, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31797000

RESUMO

Fulminant hepatitis is a serious inflammatory condition of the liver characterized by massive necrosis of liver parenchyma following excessive immune cell infiltration into the liver, and possibly causing sudden hepatic failure and medical emergency. However, the underlying mechanisms are not fully understood. Here, we investigated the role of cyclic AMP-responsive element-binding protein, hepatocyte specific (CREBH) in concanavalin A (ConA)-driven hepatitis-evoked liver injury. C57BL/6J (WT) and Crebh knockout (KO) mice injected with ConA (7.5 or 25 mg/kg) and bone marrow (BM) chimeric mice, generated by injection of BM cells into sub-lethally irradiated recipients followed by ConA injection (22.5 or 27.5 mg/kg) 8 weeks later, were used for in vivo study. Primary mouse hepatocytes and HEK293T cells were used for a comparative in vitro study. Crebh KO mice are highly susceptible to ConA-induced liver injury and prone to death due to increased neutrophil infiltration driven by enhanced hepatic expression of neutrophil-attracting chemokines. Notably, BM chimera experiment demonstrated that Crebh-deficient hepatocytes have an enhanced ability of recruiting neutrophils to the liver, thereby promoting hepatotoxicity by ConA. Intriguingly, in vitro assays showed that p65, a subunit of NF-κB and common transcription factor for various chemokines, dependent transactivation was inhibited by CREBH. Furthermore, p65 expression was inversely correlated with CREBH level in ConA-treated mice liver and TNFα-stimulated primary mouse hepatocytes. This is the first demonstration that CREBH deficiency aggravates inflammatory liver injury following chemokine-dependent neutrophil infiltration via NF-κB p65 upregulation. CREBH is suggested to be a novel therapeutic target for treatment of fulminant hepatitis.


Assuntos
Quimiocinas/metabolismo , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Necrose Hepática Massiva/patologia , Infiltração de Neutrófilos , Fator de Transcrição RelA/metabolismo , Animais , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Doença Hepática Induzida por Substâncias e Drogas/patologia , Concanavalina A/toxicidade , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Citocinas/sangue , Citocinas/metabolismo , Células HEK293 , Humanos , Masculino , Necrose Hepática Massiva/induzido quimicamente , Necrose Hepática Massiva/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Knockout , Infiltração de Neutrófilos/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos
9.
Biosyst Eng ; 129: 169-184, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32362790

RESUMO

Livestock infectious diseases, such as foot-and-mouth disease (FMD), cause substantial economic damage to livestock farms and their related industries. Among various causes of disease spread, airborne dispersion has previously been considered to be an important factor that could not be controlled by preventive measures to stop the spread of disease that focus on direct and indirect contact. Forecasting and predicting airborne virus spread are important to make time for developing strategies and to minimise the damage of the disease. To predict the airborne spread of the disease a modelling approach is important since field experiments using sensors are ineffective because of the rarefied concentrations of virus in the air. The simulation of airborne spread during past outbreaks required improvement both for farmers and for policy decision makers. In this study a free license computational fluid dynamics (CFD) code was used to simulate airborne virus spread. Forecasting data from the Korea Meteorological Administration (KMA) was directly connected in the developed model for real-time forecasting for 48 h in three-hourly intervals. To reduce computation time, scalar transport for airborne virus spread was simulated based on a database for the CFD computed airflow in the investigated area using representative wind conditions. The simulation results, and the weather data were then used to make a database for a web-based forecasting system that could be accessible to users.

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