RESUMO
BACKGROUND: Clostridioides difficile (C. difficile) is the most common pathogen causing health care-associated infections. C. difficile TcdA and TcdB have been shown to activate enteric neurons; however, what population of these cells is more profoundly influenced and the mechanism underlying these effects remain unknown. AIM: To characterize a specific population of TcdA-affected myenteric neurons and investigate the role of the P2X7 receptor in TcdA-induced ileal inflammation, cell death, and the changes in the enteric nervous system in mice. METHODS: Swiss mice were used to model TcdA-induced ileitis in ileal loops exposed to TcdA (50 µg/Loop) for 4 h. To investigate the role of the P2X7 receptor, Brilliant Blue G (50 mg/kg, i.p.), which is a nonspecific P2X7 receptor antagonist, or A438079 (0.7 µg/mouse, i.p.), which is a competitive P2X7 receptor antagonist, were injected one hour prior to TcdA challenge. Ileal samples were collected to analyze the expression of the P2X7 receptor (by quantitative real-time polymerase chain reaction and immunohistochemistry), the population of myenteric enteric neurons (immunofluorescence), histological damage, intestinal inflammation, cell death (terminal deoxynucleotidyltransferase-mediated dUTP-biotin nick end labeling), neuronal loss, and S100B synthesis (immunohistochemistry). RESULTS: TcdA upregulated (P < 0.05) the expression of the P2X7 receptor gene in the ileal tissues, increasing the level of this receptor in myenteric neurons compared to that in control mice. Comparison with the control mice indicated that TcdA promoted (P < 0.05) the loss of myenteric calretinin+ (Calr) and choline acetyltransferase+ neurons and increased the number of nitrergic+ and Calr+ neurons expressing the P2X7 receptor. Blockade of the P2X7 receptor decreased TcdA-induced intestinal damage, cytokine release [interleukin (IL)-1ß, IL-6, IL-8, and tumor necrosis factor-α], cell death, enteric neuron loss, and S100B synthesis in the mouse ileum. CONCLUSION: Our findings demonstrated that TcdA induced the upregulation of the P2X7 receptor, which promoted enteric neuron loss, S100B synthesis, tissue damage, inflammation, and cell death in the mouse ileum. These findings contribute to the future directions in understanding the mechanism involved in intestinal dysfunction reported in patients after C. difficile infection.
Assuntos
Toxinas Bacterianas , Clostridioides difficile , Ileíte , Animais , Apoptose , Biotina/metabolismo , Calbindina 2 , Colina O-Acetiltransferase/metabolismo , DNA Nucleotidilexotransferase/metabolismo , Enterotoxinas , Ileíte/induzido quimicamente , Inflamação/patologia , Interleucina-6/metabolismo , Interleucina-8/metabolismo , Camundongos , Neurônios/patologia , Antagonistas do Receptor Purinérgico P2X/farmacologia , Receptores Purinérgicos P2X7 , Fator de Necrose Tumoral alfa/metabolismoRESUMO
BACKGROUND: Mucositis is one of the most relevant gastrointestinal inflammatory conditions in humans, generated by the use of chemotherapy drugs, such as 5-fluoracil (5-FU). 5-FU-induced mucositis affects 80% of patients undergoing oncological treatment causing mucosal gut dysfunctions and great discomfort. As current therapy drugs presents limitations in alleviating mucositis symptoms, alternative strategies are being pursued. Recent studies have shown that the antimicrobial pancreatitis-associated protein (PAP) has a protective role in intestinal inflammatory processes. Indeed, it was demonstrated that a recombinant strain of Lactococcus lactis expressing human PAP (LL-PAP) could prevent and improve murine DNBS-induced colitis, an inflammatory bowel disease (IBD) that causes severe inflammation of the colon. Hence, in this study we sought to evaluate the protective effects of LL-PAP on 5-FU-induced experimental mucositis in BALB/c mice as a novel approach to treat the disease. RESULTS: Our results show that non-recombinant L. lactis NZ9000 have antagonistic activity, in vitro, against the enteroinvasive gastrointestinal pathogen L. monocytogenes and confirmed PAP inhibitory effect against Opportunistic E. faecalis. Moreover, L. lactis was able to prevent histological damage, reduce neutrophil and eosinophil infiltration and secretory Immunoglobulin-A in mice injected with 5-FU. Recombinant lactococci carrying antimicrobial PAP did not improve those markers of inflammation, although its expression was associated with villous architecture preservation and increased secretory granules density inside Paneth cells in response to 5-FU inflammation. CONCLUSIONS: We have demonstrated for the first time that L. lactis NZ9000 by itself, is able to prevent 5-FU-induced intestinal inflammation in BALB/c mice. Moreover, PAP delivered by recombinant L. lactis strain showed additional protective effects in mice epithelium, revealing to be a promising strategy to treat intestinal mucositis.
Assuntos
Antígenos de Neoplasias/genética , Antígenos de Neoplasias/metabolismo , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Ileíte/prevenção & controle , Lactococcus lactis/genética , Lactococcus lactis/fisiologia , Lectinas Tipo C/genética , Lectinas Tipo C/metabolismo , Mucosite/prevenção & controle , Animais , Antibiose , Antígenos de Neoplasias/farmacologia , Biomarcadores Tumorais/farmacologia , Modelos Animais de Doenças , Enterococcus faecalis/fisiologia , Fluoruracila , Humanos , Ileíte/induzido quimicamente , Ileíte/tratamento farmacológico , Doenças Inflamatórias Intestinais/tratamento farmacológico , Doenças Inflamatórias Intestinais/prevenção & controle , Mucosa Intestinal/metabolismo , Intestino Delgado/imunologia , Intestino Delgado/microbiologia , Intestino Delgado/patologia , Lactococcus lactis/metabolismo , Listeria monocytogenes/fisiologia , Camundongos , Camundongos Endogâmicos BALB C , Mucosite/induzido quimicamente , Mucosite/tratamento farmacológico , Mucosite/microbiologia , Proteínas Associadas a PancreatiteRESUMO
5-Fluorouracil-induced gastro-intestinal toxicity predominantly affects the upper and the lower gastro-intestinal tract. Although 5-fluorouracil (5-FU) can cause severe small-bowel toxicity, this has been reported only in 6 patients with colon carcinoma receiving 5-FU-based therapy. The presentation was extensive ulceration and inflammation of the small bowel with no involvement of the colon. We report another case of this toxicity, and discuss the diagnosis and mechanisms by which 5-FU can induce small-bowel toxicity.
Assuntos
Antimetabólitos Antineoplásicos/efeitos adversos , Neoplasias Colorretais/tratamento farmacológico , Fluoruracila/efeitos adversos , Ileíte/induzido quimicamente , Idoso , Feminino , HumanosRESUMO
The aim of this study was to evaluate the effect of ursodeoxycholic acid (UDCA) on intestinal permeability (IP) and reactive oxygen species (ROS) generation in indomethacin-induced enteropathy, a well-known experimental model of Crohn's disease. Seventy-eight male Wistar rats were randomly assigned to receive indomethacin, indomethacin + UDCA, or vehicles. Indomethacin induced a significant increase in the fraction of urinary excretion of 51Cr-EDTA following oral administration (7.9 +/- 1.3 vs 2.3 +/- 0.2%; P < 0.05) and lucigenin-amplified chemiluminescence in intestinal fragments ex vivo (10.1 +/- 1.9 vs 2.6 +/- 0.4 cpm x 10(3)/mg; P < 0.05) compared to controls. UDCA significantly reversed these effects (P < 0.05), without being incorporated in biliary bile acid composition (HPLC analysis). These findings support a local protective effect of UDCA in experimental ileitis by the modulation of intestinal barrier dysfunction and oxidative stress. In short, they provide insights into mechanisms of action of UDCA in intestinal inflammation and a new perspective on the treatment of Crohn's disease.
Assuntos
Ileíte/fisiopatologia , Mucosa Intestinal/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Ácido Ursodesoxicólico/farmacologia , Animais , Anti-Inflamatórios não Esteroides/toxicidade , Modelos Animais de Doenças , Ileíte/induzido quimicamente , Indometacina/toxicidade , Mucosa Intestinal/fisiopatologia , Masculino , Distribuição Aleatória , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismoRESUMO
Estudios recientes han mostrado que hasta el 70 por ciento de los pacientes que ingieren por largo tiempo antiinflamatorios no esteroideos desarrollan ileítis crónica y, algunos de ellos, complicaciones graves como son: síndrome de mala-absorción, perforación, hemorragia y oclusión intestinal. Informamos el caso de un hombre de 50 años con espondilitis anquilosante, tratado con antiinflamatorios no esteroideos (indometacina, fenilbutazona y naproxeno) desde los 13 años, que presento un cuadro de oclusión intestinal con síndrome abdominal agudo. Fue tratado quirúrgicamente y se encontraron las características macroscópicas y microscópicas que se presentan en la ileítis crónica por antiinflamatorios no esteroideos