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1.
Proc Natl Acad Sci U S A ; 118(39)2021 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-34548395

RESUMO

Extracellular adenosine triphosphate (ATP) released by mucosal immune cells and by microbiota in the intestinal lumen elicits diverse immune responses that mediate the intestinal homeostasis via P2 purinergic receptors, while overactivation of ATP signaling leads to mucosal immune system disruption, which leads to pathogenesis of intestinal inflammation. In the small intestine, hydrolysis of luminal ATP by ectonucleoside triphosphate diphosphohydrolase (E-NTPD)7 in epithelial cells is essential for control of the number of T helper 17 (Th17) cells. However, the molecular mechanism by which microbiota-derived ATP in the colon is regulated remains poorly understood. Here, we show that E-NTPD8 is highly expressed in large-intestinal epithelial cells and hydrolyzes microbiota-derived luminal ATP. Compared with wild-type mice, Entpd8 -/- mice develop more severe dextran sodium sulfate-induced colitis, which can be ameliorated by either the depletion of neutrophils and monocytes by injecting with anti-Gr-1 antibody or the introduction of P2rx4 deficiency into hematopoietic cells. An increased level of luminal ATP in the colon of Entpd8 -/- mice promotes glycolysis in neutrophils through P2x4 receptor-dependent Ca2+ influx, which is linked to prolonged survival and elevated reactive oxygen species production in these cells. Thus, E-NTPD8 limits intestinal inflammation by controlling metabolic alteration toward glycolysis via the P2X4 receptor in myeloid cells.


Assuntos
Adenosina Trifosfatases/fisiologia , Trifosfato de Adenosina/metabolismo , Colite/prevenção & controle , Glicólise , Células Mieloides/metabolismo , Receptores Purinérgicos P2X4/metabolismo , Células Th17/imunologia , Animais , Células Cultivadas , Colite/etiologia , Colite/metabolismo , Colite/patologia , Feminino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Células Mieloides/imunologia , Células Mieloides/patologia , Receptores Purinérgicos P2X4/genética , Transdução de Sinais
2.
Nat Commun ; 12(1): 4907, 2021 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-34389726

RESUMO

The intestinal mucosa constitutes an environment of closely regulated immune cells. Dendritic cells (DC) interact with the gut microbiome and antigens and are important in maintaining gut homeostasis. Here, we investigate DC transcriptome, phenotype and function in five anatomical locations of the gut lamina propria (LP) which constitute different antigenic environments. We show that DC from distinct gut LP compartments induce distinct T cell differentiation and cytokine secretion. We also find that PD-L1+ DC in the duodenal LP and XCR1+ DC in the colonic LP comprise distinct tolerogenic DC subsets that are crucial for gut homeostasis. Mice lacking PD-L1+ and XCR1+ DC have a proinflammatory gut milieu associated with an increase in Th1/Th17 cells and a decrease in Treg cells and have exacerbated disease in the models of 5-FU-induced mucositis and DSS-induced colitis. Our findings identify PD-L1+ and XCR1+ DC as region-specific physiologic regulators of intestinal homeostasis.


Assuntos
Antígeno B7-H1/imunologia , Células Dendríticas/imunologia , Homeostase/imunologia , Mucosa Intestinal/imunologia , Receptores de Quimiocinas/imunologia , Animais , Antígeno B7-H1/genética , Antígeno B7-H1/metabolismo , Colite/genética , Colite/imunologia , Colite/metabolismo , Citocinas/imunologia , Citocinas/metabolismo , Células Dendríticas/metabolismo , Fezes/microbiologia , Feminino , Microbioma Gastrointestinal/genética , Microbioma Gastrointestinal/imunologia , Homeostase/genética , Humanos , Mucosa Intestinal/metabolismo , Mucosa Intestinal/microbiologia , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Receptores de Quimiocinas/genética , Receptores de Quimiocinas/metabolismo , Linfócitos T/citologia , Linfócitos T/imunologia , Linfócitos T/metabolismo , Transcriptoma/genética , Transcriptoma/imunologia
3.
Int J Mol Sci ; 22(16)2021 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-34445403

RESUMO

Natural smectites have demonstrated efficacy in the treatment of diarrhea. The present study evaluated the prophylactic effect of a diosmectite (FI5pp) on the clinical course, colon damage, expression of tight junction (TJ) proteins and the composition of the gut microbiota in dextran sulfate sodium (DSS) colitis. Diosmectite was administered daily to Balb/c mice from day 1 to 7 by oral gavage, followed by induction of acute DSS-colitis from day 8 to 14 ("Control", n = 6; "DSS", n = 10; "FI5pp + DSS", n = 11). Mice were sacrificed on day 21. Clinical symptoms (body weight, stool consistency and occult blood) were checked daily after colitis induction. Colon tissue was collected for histological damage scoring and quantification of tight junction protein expression. Stool samples were collected for microbiome analysis. Our study revealed prophylactic diosmectite treatment attenuated the severity of DSS colitis, which was apparent by significantly reduced weight loss (p = 0.022 vs. DSS), disease activity index (p = 0.0025 vs. DSS) and histological damage score (p = 0.023 vs. DSS). No significant effects were obtained for the expression of TJ proteins (claudin-2 and claudin-3) after diosmectite treatment. Characterization of the microbial composition by 16S amplicon NGS showed that diosmectite treatment modified the DSS-associated dysbiosis. Thus, diosmectites are promising candidates for therapeutic approaches to target intestinal inflammation and to identify possible underlying mechanisms of diosmectites in further studies.


Assuntos
Bactérias/classificação , Colite/tratamento farmacológico , Sulfato de Dextrana/efeitos adversos , Microbiota/efeitos dos fármacos , Silicatos/administração & dosagem , Administração Oral , Animais , Bactérias/efeitos dos fármacos , Bactérias/genética , Bactérias/isolamento & purificação , Peso Corporal/efeitos dos fármacos , Colite/induzido quimicamente , Colite/metabolismo , Colite/microbiologia , DNA Bacteriano/genética , DNA Ribossômico/genética , Fezes/microbiologia , Masculino , Camundongos Endogâmicos BALB C , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Índice de Gravidade de Doença , Silicatos/farmacologia , Proteínas de Junções Íntimas/metabolismo , Resultado do Tratamento
4.
Nutrients ; 13(8)2021 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-34444876

RESUMO

Diet is considered an important trigger in inflammatory bowel diseases (IBD), as feeding habits can affect intestinal permeability and clearance of bacterial antigens, consequently influencing the immune system. Free fatty acid receptors (FFARs), expressed on the intestinal epithelial cells, belong to the family of luminal-facing receptors that are responsive to nutrients. The objective of this study was to characterize the anti-inflammatory activity and the effect on intestinal barrier function of synthetic FFAR agonists in mouse models of colitis. Therapeutic activity of GW9508 (FFAR1 agonist), 4-CMTB (FFAR2 agonist), AR420626 (FFAR3 agonist), and GSK137647 (FFAR4 agonist) was investigated in two models of semi-chronic colitis: induced by trinitrobenzenesulfonic acid (TNBS), mimicking Crohn's disease, as well as induced by dextran sulfate sodium (DSS), which recapitulates ulcerative colitis in humans. Moreover, we assessed the influence of FFARs agonists on epithelial ion transport and measured the ion flow stimulated by forskolin and veratridine. Administration of FFAR4 agonist GSK137647 attenuated both TNBS-induced and DSS-induced colitis in mice, as indicated by macroscopic parameters and myeloperoxidase activity. The action of FFAR4 agonist GSK137647 was significantly blocked by pretreatment with selective FFAR4 antagonist AH7614. Moreover, FFAR1 and FFAR4 agonists reversed the increase in the colon permeability caused by inflammation. FFAR4 restored the tight junction genes expression in mouse colon. This is the first evaluation of the anti-inflammatory activity of selective FFAR agonists, showing that pharmacological intervention targeting FFAR4, which is a sensor of medium and long chain fatty acids, attenuates intestinal inflammation.


Assuntos
Compostos de Anilina/farmacologia , Anti-Inflamatórios/farmacologia , Colite/tratamento farmacológico , Colo/efeitos dos fármacos , Mucosa Intestinal/efeitos dos fármacos , Receptores Acoplados a Proteínas G/agonistas , Sulfonamidas/farmacologia , Animais , Células CACO-2 , Colite/induzido quimicamente , Colite/metabolismo , Colite/patologia , Colo/metabolismo , Colo/patologia , Citocinas/metabolismo , Sulfato de Dextrana , Modelos Animais de Doenças , Humanos , Mediadores da Inflamação/metabolismo , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Óxido Nítrico/metabolismo , Permeabilidade , Células RAW 264.7 , Receptores Acoplados a Proteínas G/metabolismo , Proteínas de Junções Íntimas/metabolismo , Junções Íntimas/efeitos dos fármacos , Junções Íntimas/metabolismo , Junções Íntimas/patologia , Ácido Trinitrobenzenossulfônico
5.
Biomed Res Int ; 2021: 5561221, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34414236

RESUMO

Brucea javanica oil (BJO) is beneficial for the treatment of ulcerative colitis (UC), and that quassinoids in particular brusatol are bioactive components. However, it is still uncertain whether or not other components in BJO, such as oleic acid and fatty acids, have an anti-UC effect. The present study is aimed at comparing the anti-UC effects between brusatol-enriched BJO (BE-BJO) and brusatol-free BJO (BF-BJO) and at exploring the effects and mechanisms of BE-BJO on colon inflammation and intestinal epithelial barrier function. Balb/C mice received 3% (wt/vol) DSS for one week to establish the UC model. Different doses of BE-BJO, BF-BJO, or BJO were treated. The result illustrated that BE-BJO alleviated DSS-induced loss of body weight, an increase of disease activity index (DAI), and a shortening of colon, whereas BF-BJO did not have these protective effects. BE-BJO treatment improved the morphology of colon tissue, inhibited the production and release of TNF-α, IFN-γ, IL-6, and IL-1ß in the colon tissue, and reversed the decreased expressions of ZO-1, occludin, claudin-1, and E-cadherin induced by DSS but augmented claudin-2 expression. Mechanistically, BE-BJO repressed phosphorylation of NF-κB subunit p65, suppressed RhoA activation, downregulated ROCK, and prevented phosphorylation of myosin light chain (MLC) in DSS-treated mice, indicating that the protective effect of BE-BJO is attributed to suppression of NF-κB and RhoA/ROCK signaling pathways. These findings confirm that brusatol is an active component from BJO in the treatment of UC.


Assuntos
Brucea/química , Colite/tratamento farmacológico , Sulfato de Dextrana/efeitos adversos , Óleos Vegetais/administração & dosagem , Quassinas/administração & dosagem , Transdução de Sinais/efeitos dos fármacos , Animais , Peso Corporal/efeitos dos fármacos , Colite/induzido quimicamente , Colite/metabolismo , Modelos Animais de Doenças , Regulação da Expressão Gênica/efeitos dos fármacos , Masculino , Camundongos , NF-kappa B/metabolismo , Fosforilação/efeitos dos fármacos , Óleos Vegetais/química , Óleos Vegetais/farmacologia , Quassinas/farmacologia , Resultado do Tratamento , Quinases Associadas a rho/metabolismo , Proteína rhoA de Ligação ao GTP/metabolismo
7.
Am J Physiol Gastrointest Liver Physiol ; 321(3): G308-G324, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34260310

RESUMO

Intestinal mucosal healing is the primary therapeutic goal of medical treatments for inflammatory bowel disease (IBD). Epithelial stem cells are key players in the healing process. Lgr5+ stem cells maintain cellular turnover during homeostasis in the colonic crypt. However, they are lost and dispensable for repair in a wide variety of injury models, including dextran sulfate sodium (DSS) colitis, radiation, helminth infection, and T-cell activation. The direct loss of Lgr5+ cells activates a plasticity response in the epithelium in which other cell types can serve as stem cells. Whether this paradigm applies to mouse models of IBD remains unknown. In contrast to previously tested models, IBD models involve an inflammatory response rooted in the loss of immunologic tolerance to intestinal luminal contents including the microbiome. Here, we show the persistence of Lgr5+ cells in oxazolone, 2,4,6-trinitrobenzene sulfonic acid (TNBS), and Il10-/-, and Il10-/- Tnfr1-/- IBD models. This contrasts with results obtained from DSS-induced injury. Through high-throughput expression profiling, we find that these colitis models were associated with distinct patterns of cytokine expression. Direct exposure of colonic epithelial organoids to DSS, oxazolone, or TNBS resulted in increased apoptosis and loss of Lgr5+ cells. Targeted ablation of Lgr5+ cells resulted in severe exacerbation of chronic, antibody-induced IL-10-deficient colitis, but had only modest effects in TNBS-induced colitis. These results show that distinct mouse models of IBD-like colitis induce different patterns of Lgr5+ stem cell retention and function.NEW & NOTEWORTHY Acute intestinal injury and epithelial repair are associated with the loss of fast-cycling Lgr5+ stem cells and plasticity in the activation of formerly quiescent cell populations. In contrast, here we show in murine inflammatory bowel disease the persistence of the Lgr5+ stem cell population and its essential role in restricting the severity of chronic colitis. This demonstrates a diversity of stem cell responses to colitis.


Assuntos
Colite/metabolismo , Doenças Inflamatórias Intestinais/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Células-Tronco/citologia , Animais , Proliferação de Células/fisiologia , Modelos Animais de Doenças , Epitélio/metabolismo , Homeostase/fisiologia , Mucosa Intestinal/metabolismo , Camundongos , Regeneração/fisiologia , Células-Tronco/metabolismo
8.
Nat Cell Biol ; 23(7): 796-807, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34239062

RESUMO

Inflammatory bowel diseases present with elevated levels of intestinal epithelial cell (IEC) death, which compromises the gut barrier, activating immune cells and triggering more IEC death. The endogenous signals that prevent IEC death and break this vicious cycle, allowing resolution of intestinal inflammation, remain largely unknown. Here we show that prostaglandin E2 signalling via the E-type prostanoid receptor 4 (EP4) on IECs represses epithelial necroptosis and induces resolution of colitis. We found that EP4 expression correlates with an improved IBD outcome and that EP4 activation induces a transcriptional signature consistent with resolution of intestinal inflammation. We further show that dysregulated necroptosis prevents resolution, and EP4 agonism suppresses necroptosis in human and mouse IECs. Mechanistically, EP4 signalling on IECs converges on receptor-interacting protein kinase 1 to suppress tumour necrosis factor-induced activation and membrane translocation of the necroptosis effector mixed-lineage kinase domain-like pseudokinase. In summary, our study indicates that EP4 promotes the resolution of colitis by suppressing IEC necroptosis.


Assuntos
Colite/metabolismo , Colo/metabolismo , Dinoprostona/metabolismo , Células Epiteliais/metabolismo , Mucosa Intestinal/metabolismo , Necroptose , Receptores de Prostaglandina E Subtipo EP4/metabolismo , Animais , Anti-Inflamatórios/farmacologia , Colite/induzido quimicamente , Colite/patologia , Colite/prevenção & controle , Colo/efeitos dos fármacos , Colo/patologia , Sulfato de Dextrana , Modelos Animais de Doenças , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/patologia , Células HT29 , Humanos , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/patologia , MAP Quinase Quinase Quinases/genética , MAP Quinase Quinase Quinases/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Knockout , Necroptose/efeitos dos fármacos , Organoides , Proteínas Quinases/genética , Proteínas Quinases/metabolismo , Proteína Serina-Treonina Quinases de Interação com Receptores/genética , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo , Receptores de Prostaglandina E Subtipo EP4/agonistas , Receptores de Prostaglandina E Subtipo EP4/genética , Transdução de Sinais
9.
Int J Nanomedicine ; 16: 4545-4557, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34267512

RESUMO

Background: Shigella infection has always been a global burden, and it particularly threatens children between the ages of 1 and 5 years. Economically underdeveloped countries are dominated by Shigella flexneri infection. The most effective method to treat Shigella is antibiotics, but with the abuse of antibiotics and the prevalence of multidrug resistance, we urgently need a relatively safe non-antibiotic treatment to replace it. Ultrasmall Au nanoclusters (NCs) have special physical and chemical properties and can better interact with and be internalized by bacteria to disrupt the metabolic balance. The purpose of this study was to explore whether Au NCs may be a substitute for antibiotics to treat Shigella infections. Methods: Au NCs and Shigella Sf301, R2448, and RII-1 were cocultured in vitro to evaluate the bactericidal ability of Au NCs. The degree of damage and mode of action of Au NCs in Shigella were clearly observed in images of scanning electron microscopy (SEM). In vivo experiments were conducted to observe the changes in body weight, clinical disease activity index (DAI) and colon (including length and histopathological sections) of mice treated with Au NCs. The effect of Au NCs was analysed by measuring the content of lipocalin-2 (LCN2) and Shigella in faeces. Next, the changes in Shigella biofilm activity, the release of reactive oxygen species (ROS), the changes in metabolism-related and membrane-related genes, and the effect of Au NCs on the body weight of mice were determined to further analyse the mechanism of action and effect. Results: Au NCs (100 µM) interfered with oxidative metabolism genes, induced a substantial increase in ROS levels, interacted with the cell membrane to destroy it, significantly killed Shigella, and effectively alleviated the intestinal damage caused by Shigella in mice. The activity of the biofilm formed by Shigella was reduced. Conclusion: The effective antibacterial effect and good safety suggest that Au NCs represent a good potential alternative to antibiotics to treat Shigella infections.


Assuntos
Colite/metabolismo , Colite/microbiologia , Ouro/química , Ouro/farmacologia , Nanopartículas Metálicas/química , Estresse Oxidativo/efeitos dos fármacos , Shigella/fisiologia , Animais , Colite/tratamento farmacológico , Ouro/uso terapêutico , Humanos , Camundongos , Espécies Reativas de Oxigênio/metabolismo , Shigella/efeitos dos fármacos
10.
Int J Mol Sci ; 22(12)2021 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-34208517

RESUMO

Superoxide dismutase 3 (SOD3), also known as extracellular superoxide dismutase, is an enzyme that scavenges reactive oxygen species (ROS). It has been reported that SOD3 exerts anti-inflammatory abilities in several immune disorders. However, the effect of SOD3 and the underlying mechanism in inflammatory bowel disease (IBD) have not been uncovered. Therefore, in the present study, we investigated whether SOD3 can protect intestinal cells or organoids from inflammation-mediated epithelial damage. Cells or mice were treated with SOD3 protein or SOD3-transduced mesenchymal stem cells (MSCs). Caco-2 cells or intestinal organoids stimulated with pro-inflammatory cytokines were used to evaluate the protective effect of SOD3 on epithelial junctional integrity. Dextran sulfate sodium (DSS)-induced colitis mice received SOD3 or SOD3-transduced MSCs (SOD3-MSCs), and were assessed for severity of disease and junctional protein expression. The activation of the mitogen-activated protein kinase (MAPK) pathway and elevated expression of cytokine-encoding genes decreased in TNF-α-treated Caco-2 cells or DSS-induced colitis mice when treated with SOD3 or SOD3-MSCs. Moreover, the SOD3 supply preserved the expression of tight junction (ZO-1, occludin) or adherence junction (E-cadherin) proteins when inflammation was induced. SOD3 also exerted a protective effect against cytokine- or ROS-mediated damage to intestinal organoids. These results indicate that SOD3 can effectively alleviate enteritis symptoms by maintaining the integrity of epithelial junctions and regulating inflammatory- and oxidative stress.


Assuntos
Colite/etiologia , Colite/metabolismo , Mucosa Intestinal/metabolismo , Células-Tronco Mesenquimais/metabolismo , Superóxido Dismutase/genética , Junções Íntimas/metabolismo , Animais , Biomarcadores , Células CACO-2 , Colite/patologia , Citocinas/metabolismo , Modelos Animais de Doenças , Suscetibilidade a Doenças , Humanos , Imuno-Histoquímica , Mediadores da Inflamação/metabolismo , Células-Tronco Mesenquimais/citologia , Camundongos , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/metabolismo , Junções Íntimas/patologia
11.
NPJ Biofilms Microbiomes ; 7(1): 58, 2021 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-34244520

RESUMO

The low viability during gastrointestinal transit and poor mucoadhesion considerably limits the effectiveness of Ligilactobacillus salivarius Li01 (Li01) in regulating gut microbiota and alleviating inflammatory bowel disease (IBD). In this study, a delivery system was designed through layer-by-layer (LbL) encapsulating a single Li01cell with chitosan and alginate. The layers were strengthened by cross-linking to form a firm and mucoadhesive shell (~10 nm thickness) covering the bacterial cell. The LbL Li01 displayed improved viability under simulated gastrointestinal conditions and mucoadhesive function. Almost no cells could be detected among the free Li01 after 2 h incubation in digestive fluids, while for LbL Li01, the total reduction was around 3 log CFU/mL and the viable number of cells remained above 6 log CFU/mL. Besides, a 5-fold increase in the value of rupture length and a two-fold increase in the number of peaks were found in the (bacteria-mucin) adhesion curves of LbL Li01, compared to those of free Li01. Oral administration with LbL Li01 on colitis mice facilitated intestinal barrier recovery and restoration of the gut microbiota. The improved functionality of Li01 by LbL encapsulation could increase the potential for the probiotic to be used in clinical applications to treat IBD; this should be explored in future studies.


Assuntos
Técnicas Bacteriológicas , Lactobacillus/fisiologia , Animais , Aderência Bacteriana , Biomarcadores , Linhagem Celular , Colite/etiologia , Colite/metabolismo , Colite/patologia , Citocinas/metabolismo , Modelos Animais de Doenças , Suscetibilidade a Doenças , Humanos , Mediadores da Inflamação , Doenças Inflamatórias Intestinais/etiologia , Doenças Inflamatórias Intestinais/metabolismo , Camundongos , Viabilidade Microbiana , Probióticos/administração & dosagem
12.
Int J Mol Sci ; 22(14)2021 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-34299013

RESUMO

Mucosal CD4+ T lymphocytes display a potent opioid-mediated analgesic activity in interleukin (IL)-10 knockout mouse model of inflammatory bowel diseases (IBD). Considering that endogenous opioids may also exhibit anti-inflammatory activities in the periphery, we examined the consequences of a peripheral opioid receptor blockade by naloxone-methiodide, a general opioid receptor antagonist unable to cross the blood-brain barrier, on the development of piroxicam-accelerated colitis in IL-10-deficient (IL-10-/-) mice. Here, we show that IL-10-deficient mice treated with piroxicam exhibited significant alterations of the intestinal barrier function, including permeability, inflammation-related bioactive lipid mediators, and mucosal CD4+ T lymphocyte subsets. Opioid receptor antagonization in the periphery had virtually no effect on colitis severity but significantly worsened epithelial cell apoptosis and intestinal permeability. Thus, although the endogenous opioid tone is not sufficient to reduce the severity of colitis significantly, it substantially contributes to the protection of the physical integrity of the epithelial barrier.


Assuntos
Colite/metabolismo , Interleucina-10/genética , Mucosa Intestinal/efeitos dos fármacos , Naloxona/análogos & derivados , Antagonistas de Entorpecentes/administração & dosagem , Piroxicam/farmacologia , Receptores Opioides/metabolismo , Animais , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios não Esteroides/farmacologia , Apoptose/efeitos dos fármacos , Apoptose/genética , Linfócitos T CD4-Positivos/efeitos dos fármacos , Colite/induzido quimicamente , Colite/genética , Colite/patologia , Citocinas/genética , Citocinas/metabolismo , Células Epiteliais/efeitos dos fármacos , Inflamação/genética , Inflamação/metabolismo , Inflamação/patologia , Interleucina-10/metabolismo , Mucosa Intestinal/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Naloxona/farmacologia , Permeabilidade/efeitos dos fármacos , Compostos de Amônio Quaternário/farmacologia , Índice de Gravidade de Doença
13.
Int J Mol Sci ; 22(13)2021 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-34201918

RESUMO

Protein tyrosine phosphatase nonreceptor type 2 (PTPN2) plays a critical role in the pathogenesis of inflammatory bowel diseases (IBD). Mice lacking PTPN2 in dendritic cells (DCs) develop skin and liver inflammation by the age of 22 weeks due to a generalized loss of tolerance leading to uncontrolled immune responses. The effect of DC-specific PTPN2 loss on intestinal health, however, is unknown. The aim of this study was to investigate the DC-specific role of PTPN2 in the intestine during colitis development. PTPN2fl/flxCD11cCre mice were subjected to acute and chronic DSS colitis as well as T cell transfer colitis. Lamina propria immune cell populations were analyzed using flow cytometry. DC-specific PTPN2 deletion promoted infiltration of B and T lymphocytes, macrophages, and DCs into the lamina propria of unchallenged mice and elevated Th1 abundance during acute DSS colitis, suggesting an important role for PTPN2 in DCs in maintaining intestinal immune cell homeostasis. Surprisingly, those immune cell alterations did not translate into increased colitis susceptibility in acute and chronic DSS-induced colitis or T cell transfer colitis models. However, macrophage depletion by clodronate caused enhanced colitis severity in mice with a DC-specific loss of PTPN2. Loss of PTPN2 in DCs affects the composition of lamina propria lymphocytes, resulting in increased infiltration of innate and adaptive immune cells. However, this did not result in an elevated colitis phenotype, likely because increased infiltration of macrophages in the intestine upon loss of PTPN2 loss in DCs can compensate for the inflammatory effect of PTPN2-deficient DCs.


Assuntos
Colite/etiologia , Colite/metabolismo , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Macrófagos/imunologia , Macrófagos/metabolismo , Proteína Tirosina Fosfatase não Receptora Tipo 2/deficiência , Animais , Colite/patologia , Sulfato de Dextrana/efeitos adversos , Modelos Animais de Doenças , Suscetibilidade a Doenças , Mucosa Intestinal/imunologia , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Camundongos , Camundongos Transgênicos , Fosforilação , Proteína Tirosina Fosfatase não Receptora Tipo 2/genética , Proteína Tirosina Fosfatase não Receptora Tipo 2/metabolismo , Fator de Transcrição STAT1/metabolismo , Índice de Gravidade de Doença , Transdução de Sinais , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo , Subpopulações de Linfócitos T/patologia
14.
Am J Pathol ; 191(9): 1537-1549, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34139193

RESUMO

Epithelial barrier impairment is a hallmark of several pathologic processes in the gut, including inflammatory bowel diseases. Several intracellular signals prevent apoptosis in intestinal epithelial cells. Herein, we show that in colonocytes, rictor/mammalian target of rapamycin complex 2 (mTORC2) signaling is a prosurvival stimulus. Mechanistically, mTORC2 activates Akt, which, in turn, inhibits apoptosis by phosphorylating B-cell lymphoma 2 (BCL2) associated agonist of cell death (Bad) and preventing caspase-3 activation. Nevertheless, during inflammation, rictor/mTORC2 signaling declines and Akt activity is reduced. Consequently, active caspase-3 increases in surface colonocytes undergoing apoptosis/anoikis and causes epithelial barrier breakdown. Likewise, Rictor ablation in intestinal epithelial cells interrupts mTORC2/Akt signaling and increases apoptosis/anoikis of surface colonocytes without affecting the crypt architecture. The increase in epithelial permeability induced by Rictor ablation produces a mild inflammatory response in the colonic mucosa, but minimally affects the development/establishment of colitis. The data identify a previously unknown mechanism by which rictor/mTORC2 signaling regulates apoptosis/anoikis in intestinal epithelial cells during colitis and clarify its role in the maintenance of the intestinal epithelial barrier.


Assuntos
Apoptose/fisiologia , Colite/patologia , Células Epiteliais/metabolismo , Mucosa Intestinal/patologia , Proteína Companheira de mTOR Insensível à Rapamicina/metabolismo , Animais , Colite/metabolismo , Células Epiteliais/patologia , Mucosa Intestinal/metabolismo , Camundongos , Transdução de Sinais/fisiologia
15.
Biomolecules ; 11(5)2021 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-34063522

RESUMO

The use of live biotherapeutic products (LBPs), including single strains of beneficial probiotic bacteria or consortiums, is gaining traction as a viable option to treat inflammatory-mediated diseases like inflammatory bowel disease (IBD). However, LBPs' persistence in the intestine is heterogeneous since many beneficial bacteria lack mechanisms to tolerate the inflammation and the oxidative stress associated with IBD. We rationalized that optimizing LBPs with enhanced colonization and persistence in the inflamed intestine would help beneficial bacteria increase their bioavailability and sustain their beneficial responses. Our lab developed two bioengineered LBPs (SBT001/BioPersist and SBT002/BioColoniz) modified to enhance colonization or persistence in the inflamed intestine. In this study, we examined colon-derived metabolites via ultra-high performance liquid chromatography-mass spectrometry in colitic mice treated with either BioPersist or BioColoniz as compared to their unmodified parent strains (Escherichia coli Nissle 1917 [EcN] and Lactobacillus reuteri, respectively) or to each other. BioPersist administration resulted in lowered concentrations of inflammatory prostaglandins, decreased stress hormones such as adrenaline and corticosterone, increased serotonin, and decreased bile acid in comparison to EcN. In comparison to BioColoniz, BioPersist increased serotonin and antioxidant production, limited bile acid accumulation, and enhanced tissue restoration via activated purine and pyrimidine metabolism. These data generated several novel hypotheses for the beneficial roles that LBPs may play during colitis.


Assuntos
Colite/prevenção & controle , Colo/metabolismo , Escherichia coli/metabolismo , Inflamação/prevenção & controle , Lactobacillus/metabolismo , Probióticos/farmacologia , Animais , Terapia Biológica/métodos , Colite/metabolismo , Colite/microbiologia , Colite/patologia , Colo/patologia , Citocinas/metabolismo , Sulfato de Dextrana/toxicidade , Modelos Animais de Doenças , Escherichia coli/isolamento & purificação , Feminino , Inflamação/metabolismo , Inflamação/microbiologia , Inflamação/patologia , Lactobacillus/isolamento & purificação , Metaboloma , Camundongos , Camundongos Endogâmicos C57BL
16.
FASEB J ; 35(7): e21699, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34151459

RESUMO

FUT2, a protein that uses l-fucose to mediate fucosylation of intestinal epithelial cells, is one of the detected gene variants in IBD patients. We aimed to investigate whether exogenous l-fucose could be an enteral nutritional supplement to protect intestinal barrier function. The effect of l-fucose on the restoration of epithelial barrier function in both the DSS-induced colitis mouse model and LPS-stimulated Caco-2 cells was investigated, and the impact on fucosylation of epithelial cells was examined. The severity of DSS-induced colitis was significantly reduced by l-fucose. Restoration of epithelial barrier function by l-fucose was detected. Direct l-fucose-mediated protection of tight junctions was observed in Caco-2 cells. Moreover, exogenous l-fucose promoted the exogenous metabolic pathway of l-fucose, and fucosylation of epithelial cells both in vivo and in vitro. Moreover, knockout of the FUT2 gene restrained fucosylation and the protective effect of l-fucose on barrier function. The severity of colitis was not improved by l-fucose in Fut2 knockout mice. Therefore we conclude that exogenous l-fucose protects intestinal barrier function and relieves intestinal inflammation via upregulation of FUT2-mediated fucosylation of intestinal epithelial cells.


Assuntos
Colite/prevenção & controle , Células Epiteliais/efeitos dos fármacos , Fucose/farmacologia , Fucosiltransferases/fisiologia , Inflamação/prevenção & controle , Mucosa Intestinal/efeitos dos fármacos , Substâncias Protetoras/farmacologia , Animais , Colite/induzido quimicamente , Colite/metabolismo , Colite/patologia , Sulfato de Dextrana/toxicidade , Inflamação/etiologia , Inflamação/metabolismo , Inflamação/patologia , Mucosa Intestinal/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout
17.
Mol Cell Biochem ; 476(9): 3497-3512, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33999335

RESUMO

Targeting oxidative stress and inflammation by novel dietary compounds of natural origin convincingly appears to be one of the most important therapeutic strategies to keep inflammatory bowel diseases (IBD) such as ulcerative colitis disease in remission. It is imperative to investigate naturally occuring plant-derived dietary phytochemicals that are receiving attention for their therapeutic benefits to overcome the debilitating conditions of IBD. In the present study, the effect of nerolidol (NRD), a monocyclic sesquiterpene found in German Chamomile tea, was investigated in acetic acid-induced colitis model in Wistar rats. NRD was orally administered at a dose of 50 mg/kg/day either for 3 days before or 30 min after induction of IBD for 7 days, after intrarectal administration of acetic acid. The body weight, macroscopic, and microscopic analyses of the colon in different experimental groups were observed on days 0, 2, 4, and 7. Acetic acid caused significant reduction in body weight and induced macroscopic and microscopic ulcer along with a significant decline of antioxidants, concomitant to increased malondialdehyde (MDA), a marker of lipid peroxidation, and myeloperoxidase (MPO) activity, a marker of neutrophil activation. Treatment with NRD significantly improved IBD-induced reduction in body weight, improved histology, inhibited MDA formation, and restored antioxidants along with reduced MPO activity. Acetic acid also induced the release of pro-inflammatory cytokines and increased calprotectin, released by neutrophils under inflammatory conditions. NRD treatment significantly reduced calprotectin and pro-inflammatory cytokines. NRD treatment showed potential to improve disease activity and inhibit oxidative stress, lipid peroxidation, and inflammation along with histological preservation of the colon tissues.


Assuntos
Ácido Acético/toxicidade , Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Colite/tratamento farmacológico , Inflamação/prevenção & controle , Estresse Oxidativo/efeitos dos fármacos , Sesquiterpenos/farmacologia , Animais , Antibacterianos/toxicidade , Colite/induzido quimicamente , Colite/metabolismo , Colite/patologia , Citocinas/metabolismo , Glutationa/metabolismo , Inflamação/etiologia , Inflamação/metabolismo , Inflamação/patologia , Peroxidação de Lipídeos , Masculino , Ratos , Ratos Wistar
18.
Front Immunol ; 12: 628358, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34025639

RESUMO

Irinotecan (CPT-11)-induced gastrointestinal toxicity strongly limits its anticancer efficacy. Glycyrrhiza uralensis Fisch., especially flavonoids, has strong anti-inflammatory and immunomodulatory activities. Herein, we investigate the protective effect of the total flavonoids of G. uralensis (TFGU) on CPT-11-induced colitis mice from the perspective of gut microbiota and fecal metabolism. The body weight and colon length of mice were measured. Our results showed that oral administration of TFGU significantly attenuated the loss of body weight and the shortening of colon length induced by CPT-11. The elevated disease activity index and histological score of colon as well as the up-regulated mRNA and protein levels of TNF-α, IL-1ß, and IL-6 in the colonic tissue of CPT-11-treated mice were significantly decreased by TFGU. Meanwhile, TFGU restored the perturbed gut microbial structure and function in CPT-11-treated mice to near normal level. TFGU also effectively reversed the CPT-11-induced fecal metabolic disorders in mice, mainly call backing the hypoxanthine and uric acid in purine metabolism. Spearman's correlation analysis further revealed that Lactobacillus abundance negatively correlated with fecal uric acid concentration, suggesting the pivotal role of gut microbiota in CPT-11-induced colitis. Since uric acid is a ligand of the NOD-like receptor family pyrin domain containing 3 (NLRP3) inflammasome, TFGU was further validated to inhibit the activation of NLRP3 inflammasome by CPT-11. Our findings suggest TFGU can correct the overall gut microbial dysbiosis and fecal metabolic disorders in the CPT-11-induced colitis mice, underscoring the potential of using dietary G. uralensis as a chemotherapeutic adjuvant.


Assuntos
Anti-Inflamatórios/farmacologia , Bactérias/efeitos dos fármacos , Colite/prevenção & controle , Colo/efeitos dos fármacos , Fezes/microbiologia , Flavonoides/farmacologia , Microbioma Gastrointestinal/efeitos dos fármacos , Glycyrrhiza uralensis , Extratos Vegetais/farmacologia , Animais , Anti-Inflamatórios/isolamento & purificação , Bactérias/metabolismo , Colite/induzido quimicamente , Colite/metabolismo , Colite/microbiologia , Colo/metabolismo , Colo/microbiologia , Colo/patologia , Citocinas/genética , Citocinas/metabolismo , Modelos Animais de Doenças , Disbiose , Flavonoides/isolamento & purificação , Glycyrrhiza uralensis/química , Inflamassomos/metabolismo , Mediadores da Inflamação/metabolismo , Irinotecano , Masculino , Camundongos Endogâmicos C57BL , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Extratos Vegetais/isolamento & purificação
19.
Biomolecules ; 11(5)2021 04 29.
Artigo em Inglês | MEDLINE | ID: mdl-33947113

RESUMO

Cardamonin is a naturally occurring chalcone, majorly from the Zingiberaceae family, which includes a wide range of spices from India. Herein, we investigated the anti-inflammatory property of cardamonin using different in vitro and in vivo systems. In RAW 264.7 cells, treatment with cardamonin showed a reduced nitrous oxide production without affecting the cell viability and decreased the expression of iNOS, TNF-α, and IL-6, and inhibited NF-kB signaling which emphasizes the role of cardamonin as an anti-inflammatory molecule. In a mouse model of dextran sodium sulfate (DSS)-induced colitis, cardamonin treatment protected the mice from colitis. Subsequently, we evaluated the therapeutic potential of this chalcone in a colitis-associated colon cancer model. We performed microRNA profiling in the different groups and observed that cardamonin modulates miRNA expression, thereby inhibiting tumor formation. Together, our findings indicate that cardamonin has the potential to be considered for future therapy against colorectal cancer.


Assuntos
Anti-Inflamatórios/administração & dosagem , Chalconas/administração & dosagem , Colite/tratamento farmacológico , Neoplasias Colorretais/tratamento farmacológico , MicroRNAs/genética , Animais , Anti-Inflamatórios/farmacologia , Azoximetano/efeitos adversos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Chalconas/farmacologia , Colite/induzido quimicamente , Colite/complicações , Colite/metabolismo , Neoplasias Colorretais/etiologia , Neoplasias Colorretais/genética , Sulfato de Dextrana/efeitos adversos , Modelos Animais de Doenças , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Células HCT116 , Humanos , Camundongos , Óxido Nitroso/metabolismo , Células RAW 264.7 , Análise de Sequência de RNA , Transdução de Sinais/efeitos dos fármacos , Células THP-1
20.
Molecules ; 26(9)2021 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-33946346

RESUMO

Colitis causes destruction of the intestinal mucus layer and increases intestinal inflammation. The use of antioxidants and anti-inflammatory agents derived from natural sources has been recently highlighted as a new approach for the treatment of colitis. Oxyresveratrol (OXY) is an antioxidant known to have various beneficial effects on human health, such as anti-inflammatory, antibacterial activity, and antiviral activity. The aim of this study was to investigate the therapeutic effect of OXY in rats with dextran sulfate sodium (DSS)-induced acute colitis. OXY ameliorated DSS-induced colitis and repaired damaged intestinal mucosa. OXY downregulated the expression of pro-inflammatory cytokine genes (TNF-α, IL-6, and IL-1ß) and chemokine gene MCP-1, while promoting the production of anti-inflammatory cytokine IL-10. OXY treatment also suppressed inflammation via inhibiting cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) expression in the colon, as well as the activity of myeloperoxidase (MPO). OXY exhibited anti-apoptotic effects, shifting the Bax/Bcl-2 balance. In conclusion, OXY might improve DSS-induced colitis by restoring the intestinal mucus layer and reducing inflammation within the intestine.


Assuntos
Anti-Inflamatórios/farmacologia , Sulfato de Dextrana/efeitos adversos , Extratos Vegetais/farmacologia , Estilbenos/farmacologia , Animais , Biomarcadores , Colite/tratamento farmacológico , Colite/etiologia , Colite/metabolismo , Colo/efeitos dos fármacos , Colo/metabolismo , Colo/patologia , Citocinas/metabolismo , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Expressão Gênica , Humanos , Mediadores da Inflamação/metabolismo , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Óxido Nítrico Sintase Tipo II/metabolismo , Tamanho do Órgão/efeitos dos fármacos , Ratos , Baço/efeitos dos fármacos , Baço/metabolismo , Baço/patologia
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