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1.
Cell ; 186(24): 5375-5393.e25, 2023 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-37995657

RESUMO

Itch is an unpleasant sensation that evokes a desire to scratch. The skin barrier is constantly exposed to microbes and their products. However, the role of microbes in itch generation is unknown. Here, we show that Staphylococcus aureus, a bacterial pathogen associated with itchy skin diseases, directly activates pruriceptor sensory neurons to drive itch. Epicutaneous S. aureus exposure causes robust itch and scratch-induced damage. By testing multiple isogenic bacterial mutants for virulence factors, we identify the S. aureus serine protease V8 as a critical mediator in evoking spontaneous itch and alloknesis. V8 cleaves proteinase-activated receptor 1 (PAR1) on mouse and human sensory neurons. Targeting PAR1 through genetic deficiency, small interfering RNA (siRNA) knockdown, or pharmacological blockade decreases itch and skin damage caused by V8 and S. aureus exposure. Thus, we identify a mechanism of action for a pruritogenic bacterial factor and demonstrate the potential of inhibiting V8-PAR1 signaling to treat itch.


Assuntos
Peptídeo Hidrolases , Prurido , Receptor PAR-1 , Infecções Estafilocócicas , Staphylococcus aureus , Animais , Humanos , Camundongos , Peptídeo Hidrolases/metabolismo , Prurido/microbiologia , Receptor PAR-1/metabolismo , Staphylococcus aureus/enzimologia , Staphylococcus aureus/patogenicidade , Staphylococcus aureus/fisiologia , Infecções Estafilocócicas/microbiologia , Infecções Estafilocócicas/patologia
2.
Br J Clin Pharmacol ; 90(1): 107-126, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37559444

RESUMO

AIMS: Several medicinal treatments for avoiding postoperative ileus (POI) after abdominal surgery have been evaluated in randomized controlled trials (RCTs). This network meta-analysis aimed to explore the relative effectiveness of these different treatments on ileus outcome measures. METHODS: A systematic literature review was performed to identify RCTs comparing treatments for POI following abdominal surgery. A Bayesian network meta-analysis was performed. Direct and indirect comparisons of all regimens were simultaneously compared using random-effects network meta-analysis. RESULTS: A total of 38 RCTs were included in this network meta-analysis reporting on 6371 patients. Our network meta-analysis shows that prokinetics significantly reduce the duration of first gas (mean difference [MD] = 16 h; credible interval -30, -3.1; surface under the cumulative ranking curve [SUCRA] 0.418), duration of first bowel movements (MD = 25 h; credible interval -39, -11; SUCRA 0.25) and duration of postoperative hospitalization (MD -1.9 h; credible interval -3.8, -0.040; SUCRA 0.34). Opioid antagonists are the only treatment that significantly improve the duration of food recovery (MD -19 h; credible interval -26, -14; SUCRA 0.163). CONCLUSION: Based on our meta-analysis, the 2 most consistent pharmacological treatments able to effectively reduce POI after abdominal surgery are prokinetics and opioid antagonists. The absence of clear superiority of 1 treatment over another highlights the limits of the pharmacological principles available.


Assuntos
Íleus , Antagonistas de Entorpecentes , Humanos , Metanálise em Rede , Complicações Pós-Operatórias/tratamento farmacológico , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/prevenção & controle , Íleus/tratamento farmacológico , Íleus/etiologia , Íleus/prevenção & controle
3.
Bioorg Med Chem ; 90: 117366, 2023 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-37329676

RESUMO

Hura crepitans L. (Euphorbiaceae) is a thorn-covered tree widespread in South America, Africa and Asia which produces an irritating milky latex containing numerous secondary metabolites, notably daphnane-type diterpenes known as Protein Kinase C activators. Fractionation of a dichloromethane extract of the latex led to the isolation of five new daphnane diterpenes (1-5), along with two known analogs (6-7) including huratoxin. Huratoxin (6) and 4',5'-epoxyhuratoxin (4) were found to exhibit significant and selective cell growth inhibition against colorectal cancer cell line Caco-2 and primary colorectal cancer cells cultured as colonoids. The underlying mechanism of 4 and 6 was further investigated revealing the involvement of PKCζ in the cytostatic activity.


Assuntos
Neoplasias Colorretais , Diterpenos , Euphorbiaceae , Humanos , Látex , Células CACO-2 , Diterpenos/farmacologia , Neoplasias Colorretais/tratamento farmacológico
4.
Am J Physiol Gastrointest Liver Physiol ; 323(6): G609-G626, 2022 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-36283083

RESUMO

Prenatal stress is associated with a high risk of developing adult intestinal pathologies, such as irritable bowel syndrome, chronic inflammation, and cancer. Although epithelial stem cells and progenitors have been implicated in intestinal pathophysiology, how prenatal stress could impact their functions is still unknown. We have investigated the proliferative and differentiation capacities of primitive cells using epithelial crypts isolated from colons of adult male and female mice whose mothers have been stressed during late gestation. Our results show that stem cell/progenitor proliferation and differentiation in vitro are negatively impacted by prenatal stress in male progeny. This is promoted by a reinforcement of the negative proliferative/differentiation control by the protease-activated receptor 2 (PAR2) and the muscarinic receptor 3 (M3), two G protein-coupled receptors present in the crypt. Conversely, prenatal stress does not change in vitro proliferation of colon primitive cells in female progeny. Importantly, this maintenance is associated with a functional switch in the M3 negative control of colonoid growth, becoming proliferative after prenatal stress. In addition, the proliferative role of PAR2 specific to females is maintained under prenatal stress, even though PAR2-targeted stress signals Dusp6 and activated GSK3ß are increased, reaching the levels of males. An epithelial serine protease could play a critical role in the activation of the survival kinase GSK3ß in colonoids from prenatally stressed female progeny. Altogether, our results show that following prenatal stress, colon primitive cells cope with stress through sexually dimorphic mechanisms that could pave the way to dysregulated crypt regeneration and intestinal pathologies.NEW & NOTEWORTHY Primitive cells isolated from mouse colon following prenatal stress and exposed to additional stress conditions such as in vitro culture, present sexually dimorphic mechanisms based on PAR2- and M3-dependent regulation of proliferation and differentiation. Whereas prenatal stress reinforces the physiological negative control exerted by PAR2 and M3 in crypts from males, in females, it induces a switch in M3- and PAR2-dependent regulation leading to a resistant and proliferative phenotype of progenitor.


Assuntos
Colo , Receptor PAR-2 , Masculino , Feminino , Camundongos , Animais , Gravidez , Receptor PAR-2/genética , Glicogênio Sintase Quinase 3 beta , Células-Tronco , Receptores Acoplados a Proteínas G
5.
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
6.
Int J Mol Sci ; 22(18)2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34576129

RESUMO

Between 20 to 25% of Crohn's disease (CD) patients suffer from perianal fistulas, a marker of disease severity. Seton drainage combined with anti-TNFα can result in closure of the fistula in 70 to 75% of patients. For the remaining 25% of patients there is room for in situ injection of autologous or allogenic mesenchymal stem cells such as adipose-derived stem/stromal cells (ADSCs). ADSCs exert their effects on tissues and effector cells through paracrine phenomena, including the secretome and extracellular vesicles. They display anti-inflammatory, anti-apoptotic, pro-angiogenic, proliferative, and immunomodulatory properties, and a homing within the damaged tissue. They also have immuno-evasive properties allowing a clinical allogeneic approach. Numerous clinical trials have been conducted that demonstrate a complete cure rate of anoperineal fistulas in CD ranging from 46 to 90% of cases after in situ injection of autologous or allogenic ADSCs. A pivotal phase III-controlled trial using allogenic ADSCs (Alofisel®) demonstrated that prolonged clinical and radiological remission can be obtained in nearly 60% of cases with a good safety profile. Future studies should be conducted for a better knowledge of the local effect of ADSCs as well as for a standardization in terms of the number of injections and associated procedures.


Assuntos
Tecido Adiposo/citologia , Doença de Crohn/complicações , Doença de Crohn/terapia , Fístula Retal/complicações , Fístula Retal/terapia , Transplante de Células-Tronco , Células-Tronco/citologia , Animais , Ensaios Clínicos como Assunto , Humanos
7.
Proc Natl Acad Sci U S A ; 114(15): 3963-3968, 2017 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-28356517

RESUMO

The resolution of inflammation is an active process orchestrated by specialized proresolving lipid mediators (SPM) that limit the host response within the affected tissue; failure of effective resolution may lead to tissue injury. Because persistence of inflammatory signals is a main feature of chronic inflammatory conditions, including inflammatory bowel diseases (IBDs), herein we investigate expression and functions of SPM in intestinal inflammation. Targeted liquid chromatography-tandem mass spectrometry-based metabololipidomics was used to identify SPMs from n-3 polyunsaturated fatty acids in human IBD colon biopsies, quantifying a significant up-regulation of the resolvin and protectin pathway compared with normal gut tissue. Systemic treatment with protectin (PD)1n-3 DPA or resolvin (Rv)D5n-3 DPA protected against colitis and intestinal ischemia/reperfusion-induced inflammation in mice. Inhibition of 15-lipoxygenase activity reduced PD1n-3 DPA and augmented intestinal inflammation in experimental colitis. Intravital microscopy of mouse mesenteric venules demonstrated that PD1n-3 DPA and RvD5n-3 DPA decreased the extent of leukocyte adhesion and emigration following ischemia-reperfusion. These data were translated by assessing human neutrophil-endothelial interactions under flow: PD1n-3 DPA and RvD5n-3 DPA reduced cell adhesion onto TNF-α-activated human endothelial monolayers. In conclusion, we propose that innovative therapies based on n-3 DPA-derived mediators could be developed to enable antiinflammatory and tissue protective effects in inflammatory pathologies of the gut.


Assuntos
Colite/prevenção & controle , Ácidos Docosa-Hexaenoicos/farmacologia , Doenças Inflamatórias Intestinais/metabolismo , Intestinos/efeitos dos fármacos , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Estudos de Casos e Controles , Colite/induzido quimicamente , Ácidos Docosa-Hexaenoicos/metabolismo , Células Endoteliais da Veia Umbilical Humana , Humanos , Mucosa Intestinal/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Masculino , Mesentério/irrigação sanguínea , Mesentério/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Peritonite/induzido quimicamente , Peritonite/prevenção & controle , Traumatismo por Reperfusão/prevenção & controle
8.
J Lipid Res ; 60(3): 636-647, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30626624

RESUMO

Inside the human host, Leishmania infection starts with phagocytosis of infective promastigotes by macrophages. In order to survive, Leishmania has developed several strategies to manipulate macrophage functions. Among these strategies, Leishmania as a source of bioactive lipids has been poorly explored. Herein, we assessed the biosynthesis of polyunsaturated fatty acid metabolites by infective and noninfective stages of Leishmania and further explored the role of these metabolites in macrophage polarization. The concentration of docosahexaenoic acid metabolites, precursors of proresolving lipid mediators, was increased in the infective stage of the parasite compared with the noninfective stage, and cytochrome P450-like proteins were shown to be implicated in the biosynthesis of these metabolites. The treatment of macrophages with lipids extracted from the infective forms of the parasite led to M2 macrophage polarization and blocked the differentiation into the M1 phenotype induced by IFN-γ. In conclusion, Leishmania polyunsaturated fatty acid metabolites, produced by cytochrome P450-like protein activity, are implicated in parasite/host interactions by promoting the polarization of macrophages into a proresolving M2 phenotype.


Assuntos
Ácidos Graxos Insaturados/metabolismo , Interações Hospedeiro-Parasita , Leishmania/fisiologia , Animais , Células CHO , Cricetulus , Leishmania/metabolismo , Macrófagos/citologia , Macrófagos/metabolismo , Macrófagos/parasitologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fenótipo
9.
Gut ; 66(10): 1767-1778, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28096305

RESUMO

OBJECTIVES: Proteases are key mediators of pain and altered enteric neuronal signalling, although the types and sources of these important intestinal mediators are unknown. We hypothesised that intestinal epithelium is a major source of trypsin-like activity in patients with IBS and this activity signals to primary afferent and enteric nerves and induces visceral hypersensitivity. DESIGN: Trypsin-like activity was determined in tissues from patients with IBS and in supernatants of Caco-2 cells stimulated or not. These supernatants were also applied to cultures of primary afferents. mRNA isoforms of trypsin (PRSS1, 2 and 3) were detected by reverse transcription-PCR, and trypsin-3 protein expression was studied by western blot analysis and immunohistochemistry. Electrophysiological recordings and Ca2+ imaging in response to trypsin-3 were performed in mouse primary afferent and in human submucosal neurons, respectively. Visceromotor response to colorectal distension was recorded in mice administered intracolonically with trypsin-3. RESULTS: We showed that stimulated intestinal epithelial cells released trypsin-like activity specifically from the basolateral side. This activity was able to activate sensory neurons. In colons of patients with IBS, increased trypsin-like activity was associated with the epithelium. We identified that trypsin-3 was the only form of trypsin upregulated in stimulated intestinal epithelial cells and in tissues from patients with IBS. Trypsin-3 was able to signal to human submucosal enteric neurons and mouse sensory neurons, and to induce visceral hypersensitivity in vivo, all by a protease-activated receptor-2-dependent mechanism. CONCLUSIONS: In IBS, the intestinal epithelium produces and releases the active protease trypsin-3, which is able to signal to enteric neurons and to induce visceral hypersensitivity.


Assuntos
Células Epiteliais/enzimologia , Mucosa Intestinal/enzimologia , Síndrome do Intestino Irritável/enzimologia , Síndrome do Intestino Irritável/genética , Tripsina/genética , Tripsina/metabolismo , Animais , Células CACO-2 , Estudos de Casos e Controles , Colo/enzimologia , Colo/inervação , Meios de Cultivo Condicionados/farmacologia , Dipeptídeos/farmacologia , Sistema Nervoso Entérico/citologia , Sistema Nervoso Entérico/diagnóstico por imagem , Sistema Nervoso Entérico/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Feminino , Gânglios Espinais/citologia , Humanos , Hipersensibilidade/enzimologia , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/patologia , Isoxazóis/farmacologia , Lipopolissacarídeos/farmacologia , Masculino , Camundongos , Microscopia Confocal , Neurônios Aferentes/efeitos dos fármacos , Neurônios Aferentes/fisiologia , Permeabilidade/efeitos dos fármacos , RNA Mensageiro/análise , Ratos , Receptor PAR-2/antagonistas & inibidores , Receptor PAR-2/metabolismo , Tripsina/farmacologia , Tripsinogênio/genética , Regulação para Cima
10.
J Neuroinflammation ; 13(1): 132, 2016 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-27245576

RESUMO

BACKGROUND: T cell-derived opioids play a key role in the control of inflammatory pain. However, the nature of opioids produced by T cells is still matter of debate in mice. Whereas ß-endorphin has been found in T lymphocytes by using antibody-based methods, messenger RNA (mRNA) quantification shows mainly mRNA encoding for enkephalins. The objective of the study is to elucidate the nature of T cell-derived opioids responsible for analgesia and clarify discrepancy of the results at the protein and genetic levels. METHODS: CD4(+) T lymphocytes were isolated from wild-type and enkephalin-deficient mice. mRNA encoding for ß-endorphin and enkephalin was quantified by RT-qPCR. The binding of commercially available polyclonal anti-endorphin antibodies to lymphocytes from wild-type or enkephalin knockout mice was assessed by cytofluorometry. Opioid-mediated analgesic properties of T lymphocytes from wild-type and enkephalin-deficient mice were compared in a model of inflammation-induced somatic pain by measuring sensitivity to mechanical stimuli using calibrated von Frey filaments. RESULTS: CD4(+) T lymphocytes expressed high level of mRNA encoding for enkephalins but not for ß-endorphin in mice. Anti-ß-endorphin polyclonal IgG antibodies are specific for ß-endorphin but cross-react with enkephalins. Anti-ß-endorphin polyclonal antibodies bound to wild-type but not enkephalin-deficient CD4(+) T lymphocytes. Endogenous regulation of inflammatory pain by wild-type T lymphocytes was completely abolished when T lymphocytes were deficient in enkephalins. Pain behavior of immune-deficient (i.e., without B and T lymphocytes) mice was superimposable to that of mice transferred with enkephalin-deficient lymphocytes. CONCLUSIONS: Rabbit polyclonal anti-ß-endorphin serum IgG bind to CD4(+) T lymphocytes because of their cross-reactivity towards enkephalins. Thus, staining of T lymphocytes by anti-ß-endorphin polyclonal IgG reported in most of studies in mice is because of their binding to enkephalins. In mice, CD4(+) T lymphocytes completely lose their analgesic opioid-mediated activity when lacking enkephalins.


Assuntos
Analgesia/métodos , Linfócitos T CD4-Positivos/metabolismo , Encefalinas/metabolismo , Medição da Dor/métodos , Dor/metabolismo , Dor/prevenção & controle , Sequência de Aminoácidos , Animais , Linfócitos T CD4-Positivos/imunologia , Encefalinas/genética , Encefalinas/imunologia , Masculino , Camundongos , Camundongos da Linhagem 129 , Camundongos Endogâmicos C57BL , Camundongos Knockout , Dor/imunologia , Coelhos , Distribuição Aleatória
11.
Microb Cell Fact ; 14: 26, 2015 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-25889561

RESUMO

BACKGROUND: Different studies have described the successful use of recombinant lactic acid bacteria (recLAB) to deliver anti-inflammatory molecules at the mucosal level to treat Inflammatory Bowel Disease (IBD). METHODS: In order to identify the best strategy to treat IBD using recLAB, we compared the efficacy of different recombinant strains of Lactococcus lactis (the model LAB) secreting two types of anti-inflammatory molecules: cytokines (IL-10 and TGF-ß1) and serine protease inhibitors (Elafin and Secretory Leukocyte Protease Inhibitor: SLPI), using a dextran sulfate sodium (DSS)-induced mouse model of colitis. RESULTS: Our results show that oral administration of recombinant L. lactis strains expressing either IL-10 or TGF-ß1 display moderate anti-inflammatory effects in inflamed mice and only for some clinical parameters. In contrast, delivery of either serine protease inhibitors Elafin or SLPI by recLAB led to a significant reduction of intestinal inflammation for all clinical parameters tested. Since the best results were obtained with Elafin-producing L. lactis strain, we then tried to enhance Elafin expression and hence its delivery rate by producing it in a L. lactis mutant strain inactivated in its major housekeeping protease, HtrA. Strikingly, a higher reduction of intestinal inflammation in DSS-treated mice was observed with the Elafin-overproducing htrA strain suggesting a dose-dependent Elafin effect. CONCLUSIONS: Altogether, these results strongly suggest that serine protease inhibitors are the most efficient anti-inflammatory molecules to be delivered by recLAB at the mucosal level for IBD treatment.


Assuntos
Interleucina-10/metabolismo , Lactococcus lactis/metabolismo , Inibidores de Serina Proteinase/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Administração Oral , Animais , Colite/microbiologia , Colite/patologia , Colite/terapia , Modelos Animais de Doenças , Elafina/genética , Elafina/metabolismo , Expressão Gênica/efeitos dos fármacos , Interleucina-10/genética , Camundongos , Camundongos Endogâmicos C57BL , Nisina/farmacologia , Inibidor Secretado de Peptidases Leucocitárias/genética , Inibidor Secretado de Peptidases Leucocitárias/metabolismo , Inibidores de Serina Proteinase/genética , Fator de Crescimento Transformador beta/genética
12.
Nat Genet ; 37(1): 56-65, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15619623

RESUMO

Mutations in SPINK5, encoding the serine protease inhibitor LEKTI, cause Netherton syndrome, a severe autosomal recessive genodermatosis. Spink5(-/-) mice faithfully replicate key features of Netherton syndrome, including altered desquamation, impaired keratinization, hair malformation and a skin barrier defect. LEKTI deficiency causes abnormal desmosome cleavage in the upper granular layer through degradation of desmoglein 1 due to stratum corneum tryptic enzyme and stratum corneum chymotryptic enzyme-like hyperactivity. This leads to defective stratum corneum adhesion and resultant loss of skin barrier function. Profilaggrin processing is increased and implicates LEKTI in the cornification process. This work identifies LEKTI as a key regulator of epidermal protease activity and degradation of desmoglein 1 as the primary pathogenic event in Netherton syndrome.


Assuntos
Caderinas/metabolismo , Serina Endopeptidases/metabolismo , Inibidores de Serina Proteinase/genética , Serpinas/genética , Dermatopatias Genéticas/metabolismo , Animais , Desmogleína 1 , Epiderme/patologia , Epiderme/ultraestrutura , Calicreínas/metabolismo , Camundongos , Camundongos Knockout , Microscopia Eletrônica , Inibidor de Serinopeptidase do Tipo Kazal 5 , Inibidores de Serina Proteinase/metabolismo , Serpinas/metabolismo , Dermatopatias Genéticas/patologia
13.
F S Rep ; 5(1): 114-122, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38524220

RESUMO

Objective: To explore the functional implications of a homozygous CATSPER 2 (cation channel for sperm) deletion within the acrosome reaction pathway during fertilization in 2 brothers, who have unexplained infertility and hearing loss. Design: Case report. Patients: Two twin brothers aged 30 years with hearing loss and unexplained infertility. Exposure or Intervention: Molecular genetic diagnosis of deafness. Evaluation of the acrosome reaction and calcium mobilization assays after induction by progesterone and ionomycin on spermatozoa of the CATSPER 2-mutated patient and on fertile controls. Main Outcome Measures: Fertilization rate during conventional in vitro fertilization. Molecular genetic test. Percentage of acrosome-reacted spermatozoa with peanut agglutinin lectin staining. Recording of progesterone and ionomycin-induced intracellular calcium signals with a fluorescent probe. Results: Mr. S and his brother have normal, conventional sperm parameters. Both brothers have had repeated intrauterine insemination failures and one fertilization failure after conventional in vitro fertilization. Mr. S obtained 2 healthy babies after intracytoplasmic sperm injection. Genetic analysis found a homozygote deletion of the STRC (stereocilin) gene (NM 153700: c.1-? 5328+?del) that removes the CATSPER 2 gene. Mutation of the STRC gene is known to be associated with hearing loss. Sperm functional tests revealed an inability of progesterone to activate intracellular calcium signaling and to induce acrosome reaction. Conclusion: We demonstrate the absence of a calcium signal and acrosome reaction after progesterone in our patient with a CATSPER 2 mutation. We emphasize the importance of the male medical interview and of the genetic investigation of hearing loss. We show that in vitro fertilization-intracytoplasmic sperm injection is necessary, even where normal sperm parameters are present.

14.
Gut Microbes ; 16(1): 2387857, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39171684

RESUMO

Imbalances in proteolytic activity have been linked to the development of inflammatory bowel diseases (IBD) and experimental colitis. Proteases in the intestine play important roles in maintaining homeostasis, but exposure of mucosal tissues to excess proteolytic activity can promote pathology through protease-activated receptors (PARs). Previous research implicates microbial proteases in IBD, but the underlying pathways and specific interactions between microbes and PARs remain unclear. In this study, we investigated the role of microbial proteolytic activation of the external domain of PAR2 in intestinal injury using mice expressing PAR2 with a mutated N-terminal external domain that is resistant to canonical activation by proteolytic cleavage. Our findings demonstrate the key role of proteolytic cleavage of the PAR2 external domain in promoting intestinal permeability and inflammation during colitis. In wild-type mice expressing protease-sensitive PAR2, excessive inflammation leads to the expansion of bacterial taxa that cleave the external domain of PAR2, exacerbating colitis severity. In contrast, mice expressing mutated protease-resistant PAR2 exhibit attenuated colitis severity and do not experience the same proteolytic bacterial expansion. Colonization of wild-type mice with proteolytic PAR2-activating Enterococcus and Staphylococcus worsens colitis severity. Our study identifies a previously unknown interaction between proteolytic bacterial communities, which are shaped by inflammation, and the external domain of PAR2 in colitis. The findings should encourage new therapeutic developments for IBD by targeting excessive PAR2 cleavage by bacterial proteases.


Assuntos
Colite , Proteólise , Receptor PAR-2 , Animais , Receptor PAR-2/metabolismo , Receptor PAR-2/genética , Colite/microbiologia , Colite/patologia , Colite/metabolismo , Camundongos , Microbioma Gastrointestinal , Camundongos Endogâmicos C57BL , Inflamação/metabolismo , Inflamação/microbiologia , Enterococcus/genética , Enterococcus/metabolismo , Mucosa Intestinal/microbiologia , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Bactérias/genética , Bactérias/metabolismo , Bactérias/classificação , Bactérias/enzimologia , Modelos Animais de Doenças , Humanos , Domínios Proteicos , Doenças Inflamatórias Intestinais/microbiologia , Doenças Inflamatórias Intestinais/metabolismo , Doenças Inflamatórias Intestinais/patologia
15.
Br J Pharmacol ; 181(16): 2725-2749, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38637276

RESUMO

BACKGROUND AND PURPOSE: Chymotrypsin is a pancreatic protease secreted into the lumen of the small intestine to digest food proteins. We hypothesized that chymotrypsin activity may be found close to epithelial cells and that chymotrypsin signals to them via protease-activated receptors (PARs). We deciphered molecular pharmacological mechanisms and gene expression regulation for chymotrypsin signalling in intestinal epithelial cells. EXPERIMENTAL APPROACH: The presence and activity of chymotrypsin were evaluated by Western blot and enzymatic activity tests in the luminal and mucosal compartments of murine and human gut samples. The ability of chymotrypsin to cleave the extracellular domain of PAR1 or PAR2 was assessed using cell lines expressing N-terminally tagged receptors. The cleavage site of chymotrypsin on PAR1 and PAR2 was determined by HPLC-MS analysis. The chymotrypsin signalling mechanism was investigated in CMT93 intestinal epithelial cells by calcium mobilization assays and Western blot analyses of (ERK1/2) phosphorylation. The transcriptional consequences of chymotrypsin signalling were analysed on colonic organoids. KEY RESULTS: We found that chymotrypsin was present and active in the vicinity of the colonic epithelium. Molecular pharmacological studies have shown that chymotrypsin cleaves both PAR1 and PAR2 receptors. Chymotrypsin activated calcium and ERK1/2 signalling pathways through PAR2, and this pathway promoted interleukin-10 (IL-10) up-regulation in colonic organoids. In contrast, chymotrypsin disarmed PAR1, preventing further activation by its canonical agonist, thrombin. CONCLUSION AND IMPLICATIONS: Our results highlight the ability of chymotrypsin to signal to intestinal epithelial cells via PARs, which may have important physiological consequences in gut homeostasis.


Assuntos
Quimotripsina , Mucosa Intestinal , Receptor PAR-1 , Receptor PAR-2 , Animais , Humanos , Camundongos , Quimotripsina/metabolismo , Mucosa Intestinal/metabolismo , Camundongos Endogâmicos C57BL , Receptor PAR-1/metabolismo , Receptor PAR-2/metabolismo , Transdução de Sinais
16.
Proc Natl Acad Sci U S A ; 107(49): 21076-81, 2010 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-21088222

RESUMO

A growing body of evidence suggests that the multifunctional protein E4F1 is involved in signaling pathways that play essential roles during normal development and tumorigenesis. We generated E4F1 conditional knockout mice to address E4F1 functions in vivo in newborn and adult skin. E4F1 inactivation in the entire skin or in the basal compartment of the epidermis induces skin homeostasis defects, as evidenced by transient hyperplasia in the interfollicular epithelium and alteration of keratinocyte differentiation, followed by loss of cellularity in the epidermis and severe skin ulcerations. E4F1 depletion alters clonogenic activity of epidermal stem cells (ESCs) ex vivo and ends in exhaustion of the ESC pool in vivo, indicating that the lesions observed in the E4F1 mutant skin result, at least in part, from cell-autonomous alterations in ESC maintenance. The clonogenic potential of E4F1 KO ESCs is rescued by Bmi1 overexpression or by Ink4a/Arf or p53 depletion. Skin phenotype of E4F1 KO mice is also delayed in animals with Ink4a/Arf and E4F1 compound gene deficiencies. Our data identify a regulatory axis essential for ESC-dependent skin homeostasis implicating E4F1 and the Bmi1-Arf-p53 pathway.


Assuntos
Proteínas de Ligação a DNA/fisiologia , Células Epidérmicas , Homeostase , Células-Tronco/fisiologia , Fatores de Transcrição/fisiologia , Fatores Etários , Animais , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Camundongos , Camundongos Knockout , Proteínas Nucleares/metabolismo , Fenótipo , Complexo Repressor Polycomb 1 , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Repressoras/metabolismo , Células-Tronco/citologia , Proteína Supressora de Tumor p53/metabolismo , Ubiquitina-Proteína Ligases
17.
Br J Pharmacol ; 180(2): 144-160, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36355635

RESUMO

Elafin and its precursor trappin-2 are known for their contribution to the physiological mucosal shield against luminal microbes. Such a contribution seems to be particularly relevant in the gut, where the exposure of host tissues to heavy loads of microbes is constant and contributes to mucosa-associated pathologies. The expression of trappin-2/elafin has been shown to be differentially regulated in diseases associated with gut inflammation. Accumulating evidence has demonstrated the protective effects of trappin-2/elafin in gut intestinal disorders associated with acute or chronic inflammation, or with gluten sensitization disorders. The protective effects of trappin-2/elafin in the gut are discussed in terms of their pleiotropic modes of action: acting as protease inhibitors, transglutaminase substrates, antimicrobial peptides or as a regulator of pro-inflammatory transcription factors. Further, the question of the therapeutic potential of trappin-2/elafin delivery at the intestinal mucosa surface is raised. Whether trappin-2/elafin mucosal delivery should be considered to ensure intestinal tissue repair is also discussed.


Assuntos
Elafina , Enteropatias , Humanos , Elafina/metabolismo , Inibidores de Proteases , Inflamação , Enteropatias/tratamento farmacológico
18.
Essays Biochem ; 67(3): 331-344, 2023 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-36912232

RESUMO

Inflammatory bowel diseases (IBD) are modern diseases, with incidence rising around the world. They are associated with perturbation of the intestinal microbiota, and with alteration and crossing of the mucus barrier by the commensal bacteria that feed on it. In the process of mucus catabolism and invasion by gut bacteria, carbohydrate-active enzymes (CAZymes) play a critical role since mucus is mainly made up by O- and N-glycans. Moreover, the occurrence of IBD seems to be associated with low-fiber diets. Conversely, supplementation with oligosaccharides, such as human milk oligosaccharides (HMOs), which are structurally similar to intestinal mucins and could thus compete with them towards bacterial mucus-degrading CAZymes, has been suggested to prevent inflammation. In this mini-review, we will establish the current state of knowledge regarding the identification and characterization of mucus-degrading enzymes from both cultured and uncultured species of gut commensals and enteropathogens, with a particular focus on the present technological opportunities available to further the discovery of mucus-degrading CAZymes within the entire gut microbiome, by coupling microfluidics with metagenomics and culturomics. Finally, we will discuss the challenges to overcome to better assess how CAZymes targeting specific functional oligosaccharides could be involved in the modulation of the mucus-driven cross-talk between gut bacteria and their host in the context of IBD.


Assuntos
Doenças Inflamatórias Intestinais , Mucinas , Humanos , Mucinas/metabolismo , Mucosa Intestinal/metabolismo , Mucosa Intestinal/microbiologia , Doenças Inflamatórias Intestinais/metabolismo , Carboidratos , Polissacarídeos/metabolismo , Bactérias/metabolismo
19.
Br J Pharmacol ; 179(13): 3283-3305, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35048360

RESUMO

Postoperative ileus (POI) is a frequent complication after abdominal surgery. The consequences of postoperative ileus can be potentially serious such as bronchial inhalation or acute functional renal failure. Numerous advances in peri-operative management, particularly early rehabilitation, have made it possible to decrease postoperative ileus. Despite this, the rate of prolonged postoperative ileus remains high and can be as high as 25% of patients in colorectal surgery. From a pathophysiological point of view, postoperative ileus has two phases, an early neurological phase and a later inflammatory phase, to which we could add a 'pharmacological' phase during which analgesic drugs, particularly opiates, play a central role. The aim of this review article is to describe the phases of the pathophysiology of postoperative ileus, to analyse the pharmacological treatments currently available through published clinical trials and finally to discuss the different research areas for potential pharmacological targets.


Assuntos
Íleus , Analgésicos Opioides/uso terapêutico , Humanos , Íleus/tratamento farmacológico , Íleus/etiologia , Complicações Pós-Operatórias/tratamento farmacológico , Complicações Pós-Operatórias/etiologia , Fatores de Risco
20.
Cancers (Basel) ; 14(3)2022 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-35158797

RESUMO

Proctocolectomy with ileal pouch-anal anastomosis is the intervention of choice for ulcerative colitis and familial adenomatous polyposis requiring surgery. One of the long-term complications is pouch cancer, having a poor prognosis. The risk of high-grade dysplasia and cancer in the anal transitional zone and ileal pouch after 20 years is estimated to be 2 to 4.5% and 3 to 10% in ulcerative colitis and familial polyposis, respectively. The risk factors for ulcerative colitis are the presence of pre-operative dysplasia or cancer, disease duration > 10 years and severe villous atrophy. For familial polyposis, the risk factors are the number of pre-operative polyps > 1000, surgery with stapled anastomosis and the duration of follow-up. In the case of ulcerative colitis, a pouchoscopy should be performed annually if one of the following is present: dysplasia and cancer at surgery, primary sclerosing cholangitis, villous atrophy and active pouchitis (every 5 years without any of these factors). In the case of familial polyposis, endoscopy is recommended every year including chromoendoscopy. Even if anal transitional zone and ileal pouch cancers seldom occur following proctectomy for ulcerative colitis and familial adenomatous polyposis, the high mortality rate associated with this complication warrants endoscopic monitoring.

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