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Inflammatory bowel diseases (IBD), including ulcerative colitis, are chronic and idiopathic inflammations of the gastrointestinal tract. A disruption of the epithelial barrier and an imbalance between Th1 and Th2 subsets are associated with the onset and progression of these diseases. Mesenchymal stromal cells (MSC) are a promising therapy for IBD. However, cell-tracking studies have shown that intravenously infused MSC localize to the lungs and present short-term survival. To reduce practical complexities arising from living cells, we generated membrane particles (MP) from MSC membranes, which possess some of the immunomodulatory properties of MSC. This study investigated the effect of MSC-derived MP and conditioned media (CM) as cell-free therapies in the dextran sulfate sodium (DSS)-induced colitis model. Acute colitis was induced in C57BL/6 mice by oral administration of 2% DSS in drinking water ad libitum from days 0 to 7. Mice were treated with MP, CM, or living MSC on days 2 and 5. Our findings revealed that MP, CM, and living MSC ameliorated DSS-induced colitis by reducing colonic inflammation, the loss of colonic goblet cells, and intestinal mucosa permeability, preventing apoptosis of damaged colonic cells and balancing Th1 and Th2 activity. Therefore, MSC-derived MP have high therapeutic potential for treating IBD, overcoming the deficiencies of living MSC therapy, and opening novel frontiers in inflammatory diseases medicine.

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BACKGROUND: Rheumatoid arthritis (RA) is a chronic inflammatory disease characterized by synovial inflammation, fibroblast-like synoviocytes (FLS) activation and joint destruction. Fasciola hepatica is a platyhelminth that releases excretory-secretory immunomodulatory products capable of suppressing the Th1 immune response. Despite the effectiveness of available treatments for inducing disease remission, current options are not successful in all patients and may cause side effects. Thus, we evaluated the therapeutic potential of F. hepatica extract on FLS from RA patients and arthritis models. METHODS: FLS were isolated from synovial fluid of RA patients, cultured, and exposed to F. hepatica extract (60, 80, and 100 µg/ml) for different time points to assess cell viability, adherence, migration and invasion. For in vivo experiments, mice with antigen (AIA) and collagen (CIA) induced arthritis received a 200 µg/dose of F. hepatica extract daily. Statistical analysis was performed by ANOVA and Student's t-test using GraphPad Prism 6.0. RESULTS: In vitro assays showed that extract decreased FLS cell viability at concentration of 100 µg/ml (83.8% ± 5.0 extract vs. 100.0% ± 0.0 control; p < 0.05), adherence in 20% (92.0 cells ± 5.8 extract vs. 116.3 cells ± 7.9 control; p < 0.05), migratory potential (69.5% ± 17.6 extract vs. 100.0% control; p < 0.05), and cell invasiveness potential through the matrigel (76.0% ± 8.4 extract vs. 100.0% control; p < 0.01). The extract reduced leukocyte migration by 56% (40 × 104 leukocytes/knee ± 19.00) compared to control (90.90 × 104 leukocytes/knee ± 12.90) (p < 0.01) and nociception (6.37 g ± 0.99 extract vs. 3.81 g ± 1.44 control; p < 0.001) in AIA and delayed clinical onset of CIA (11.75 ± 2.96 extract vs. 14.00 ± 2.56 control; p = 0.126). CONCLUSION: Our results point out a potential immunomodulatory effect of F. hepatica extract in RA models. Therefore, the characterization of promising new immunomodulatory molecules should be pursued, as they can promote the development of new therapies. Trial registration Collection of synovial liquid and in vitro procedures were approved by the Ethics Committee with Certificate of Presentation of Ethical Appreciation in Plataforma Brasil (CAAE: 89044918.8.0000.5327; date of registration: 26/07/2018).

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INTRODUCTION: Several strains of the free-living genus Acanthamoeba can cause granulomatous amoebic encephalitis (GAE), a rare chronic and slowly progressive infection of the central nervous system (CNS), and Acanthamoeba keratitis (AK), a sight-threatening eye infectious disease. AK incidence has increased with the popularization of the contact lens wear and its treatment is currently limited and frequently unsuccessful. As imidazolium salts (IS), cationic imidazole derivatives, have promising antimicrobial potential. MATERIALS AND METHODS: The present study evaluated the amoebicidal activity of four IS; 1-n-hexadecyl-3-methylimidazolium methanesulfonate (C16MImMeS), chloride (C16MImCl) and bis (triluoromethylsulfonyl) imide (C16MImNTf2 ), and 1-methyl-3-n-octadecylimidazolium chloride (C18MImCl), against the Acanthamoeba castellanii (ATCC30010) environmental strain and a clinical isolate (genotype T4). RESULTS: Three IS showed being lethal to 100% of the Acanthamoeba trophozoites at the minimum inhibitory concentrations of 125 and 62.5 µg/mL (C16MImMeS), 31.25 and 62.5 µg/mL (C16MImCl), and 125 and 125 µg/mL (C18MImCl) for ATCC30010 and isolate T4, respectively. C16MImNTf2 did not demonstrate amoebicidal activity. All active IS caused the hemolysis of erythrocytes. The cytotoxic effect of the IS was tested in RAW macrophages and human brain microvascular endothelial cells, which demonstrated cytotoxicity in all concentrations tested against both cell lines. As a consequence, these IS with amoebicidal activity presented low selectivity index values (SI) (SI < 1.0), demonstrating lack of parasite selectivity. CONCLUSION: Thus, C16MImMeS, C16MImCl, and C18MImCl seem to hold greater promise as components for contact lens cleaning and disinfection solutions, instead of direct human application.

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Systemic lupus erythematosus (SLE) is a multifactorial and autoimmune inflammatory disease with pleomorphic clinical manifestations involving different organs and tissues. The study of different murine models has provided a better understanding of these autoimmune phenomena. Pristane-induced lupus represents a suitable model to study factors that could influence the induction and/or progression of SLE, including genetic factors. The objective of the present study was to evaluate the development and evolution of SLE after vitamin D supplementation in PIL model. Here, we evaluated the effects of vitamin D supplementation in model of pristane-induced SLE in female BALB/c mice. The animals were randomly divided into three groups: control group (CO), pristane-induced lupus group (PIL) and pristane-induced lupus group plus vitamin D (VD). Lupus was induced in PIL and VD groups using pristane. PIL group showed arthritis and kidney injury, characterized by increased proteinuria, glomerular mesangial expansion and inflammation. Moreover, PIL model showed increased levels of IL-6, TNF-α and IFN-γ in serum. We observed that treatment with vitamin D improved arthritis through reduced of incidence and arthritis clinical score and edema, but does not influenced renal injury. Treatment with vitamin D was not able to reduce proteinuria levels, decrease mesangial hypercellularity or IgG and IgM deposition in the kidney. Vitamin D supplementation did not alter IL-6, TNF-α, IL-2 and IL-4, but reduce IFN-γ. These results support that the role of vitamin D may be different depending on acting site, what could explain different responses according clinical phenotype. Therefore, further investigations of vitamin D are needed to explore the supplement dosage, timing, and the molecular basis in SLE.

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BACKGROUND AIMS: Although mesenchymal stromal cells (MSCs) have shown therapeutic potential in intestinal tissue repair, controversy concerning their short survival and poor biodistribution in recipient tissues still remains. Therefore, we investigated the paracrine role of MSC in three-dimensional culture of colon with experimental colitis. METHODS: Colitis was induced in mice by oral administration of dextran sulfate sodium (DSS) for 7 days. Inflammatory responses were assessed on the basis of clinical signs, morphological, and histopathological parameters. On days 2 and 5, colonic explants were removed, and a three-dimensional culture was performed. The structural integrity of the intestinal mucosa was tested by treating the cultures with MSC or conditioned medium (CM) for 24 h, and then the colons were analyzed for histology/immunohistochemistry and interleukin (IL)-6 production. RESULTS: Histological analysis demonstrated that both MSC and CM treatment reduced colon damage in organ culture. An increase in cell proliferation (Ki-67 staining) was observed after CM treatment. Additionally, MSC treatment was able to reduce CD3+ cells. The therapeutic effect of MSC and CM was mediated by the downregulation of IL-6. DISCUSSION: The intestinal in vitro model has shown to be potentially useful for studying cellular interactions in a three-dimensional cell arrangement. Moreover, our results provide strong evidence that both MSC and CM treatments can alleviate colonic damage in organ culture. Importantly, these results suggest that MSC-secreted factors are able to protect the colon from inflammation caused by DSS-induced colitis independent of cell transplantation.

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OBJECTIVE: To investigate the effects of oxidative stress injury in dextran sulfate sodium (DSS)-induced colitis in mice treated with mesenchymal stem cells (MSC). RESULTS: Mice exposed to oral administration of 2% DSS over 7 days presented a high disease activity index and an intense colonic inflammation. Systemic infusion of MSC protected from severe colitis, reducing weight loss and diarrhea while lowering the infiltration of inflammatory cells. Moreover, toxic colitis injury increased oxidative stress. Administration of DSS decreased reduced glutathione (GSH) and superoxide dismutase (SOD) activity, and increased thiobarbituric acid-reactive substances levels in the colon. No alteration was found in catalase (CAT) and glutathione peroxidase (GPx) activity. Otherwise, MSC transplantation was able to prevent the decrease of GSH levels and SOD activity suggestive of an antioxidant property of MSC. CONCLUSION: The oxidative stress is a pathomechanism underlying the pathophysiology of colitis and MSC play an important role in preventing the impairment of antioxidants defenses in inflamed colon.

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Background: Colitis murine models have become essential tools to investigate the molecular and cellular mechanisms that lead to inflammatory bowel disease (IBD), such as ulcerative colitis (UC). DSS-induced colitis model faithfully reproduces many of the clinical presentation and immunological disturbances observed in UC. Notwithstanding mice can show differential susceptibilities and responsiveness to dextran sodium sulfate (DSS), and varying DSS concentration and molecular weights appear to be associated with the severity of inflammation. The aim of this study was to analyze the features of mice induced colitis using different DSS concentrations and molecular weights. Materials, Methods and Results: C57BL/6 mice received 2% of high molecular weight DSS (36 000 - 50 000) in drinking water (HDSS2%) or 5% of the same molecular weight (HDSS5%); other group received 5% of low molecular weight DSS (10 000) (LDSS5%). During the 7 days of DSS administration, animals were observed for weight loss, stool consistency and presence of blood feces to determine the disease activity index (DAI). On day 8, colons were removed, measured and weighed for indirect assessment of inflammation. The tissue samples were processed for histological analysis and blood samples were collected for hematological analysis. Our results demonstrated that HDSS5% group began to show significant clinical signs sta

Background: Colitis murine models have become essential tools to investigate the molecular and cellular mechanisms that lead to inflammatory bowel disease (IBD), such as ulcerative colitis (UC). DSS-induced colitis model faithfully reproduces many of the clinical presentation and immunological disturbances observed in UC. Notwithstanding mice can show differential susceptibilities and responsiveness to dextran sodium sulfate (DSS), and varying DSS concentration and molecular weights appear to be associated with the severity of inflammation. The aim of this study was to analyze the features of mice induced colitis using different DSS concentrations and molecular weights. Materials, Methods and Results: C57BL/6 mice received 2% of high molecular weight DSS (36 000 - 50 000) in drinking water (HDSS2%) or 5% of the same molecular weight (HDSS5%); other group received 5% of low molecular weight DSS (10 000) (LDSS5%). During the 7 days of DSS administration, animals were observed for weight loss, stool consistency and presence of blood feces to determine the disease activity index (DAI). On day 8, colons were removed, measured and weighed for indirect assessment of inflammation. The tissue samples were processed for histological analysis and blood samples were collected for hematological analysis. Our results demonstrated that HDSS5% group began to show significant clinical signs sta

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Background: Platelet rich plasma (PRP) is a blood-derived source of growth factors and several cytokines, which are essential for tissue regeneration and important for wound healing due to their angiogenic, mitogenic, and chemotactic activities. To date no protocol has been established for PRP production. Standardization of this technique should consider fundamental factors such as experimental model used, blood collection method, anticoagulant choice, rotation and amount of centrifugations, elapsed time between sample activation and its clinical use in order to ensure quality and biological effects of the product. This study aimed to compare three protocols for PRP achievement in order to evaluate platelet enrichment ability and method reproducibility for further use in clinical investigations regarding PRP therapeutic properties. Materials, Methods & Results: New Zealand higid rabbits whole blood was collected in tubes containing sodium citrate. Samples were obtained through exsanguination, via abdominal aortic puncture, and separated in four aliquots designed for PRP processing and basal platelet count. The count was conducted at the time blood was collected and after every concentration protocol. Methods were tested in triplicates, and three different individuals repeated each technique for three times, reaching 27 repetitions. Selected methodologies consisted in two c

O plasma rico em plaquetas derivado de sangue autólogo é definido como um volume de plasma com uma concentração plaquetária acima dos níveis fisiológicos. É uma fonte autógena e de baixo custo de fatores de crescimento (FC). FC são moléculas bioativas fundamentais no reparo e regeneração de diversos tecidos, capazes de estimular a mitogênese, angiogênese, quimiotaxia, proliferação e diferenciação celular. Entre os fatores liberados pelas plaquetas destacam-se: Fator de Crescimento Derivado de Plaquetas (PDGF), Fator de Crescimento Transformador Beta (TGF- ), Fator de Crescimento Endotelial Vascular (VEGF) e Fator de Crescimento Epitelial (EGF). [...]

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Background: Platelet rich plasma (PRP) is a blood-derived source of growth factors and several cytokines, which are essential for tissue regeneration and important for wound healing due to their angiogenic, mitogenic, and chemotactic activities. To date no protocol has been established for PRP production. Standardization of this technique should consider fundamental factors such as experimental model used, blood collection method, anticoagulant choice, rotation and amount of centrifugations, elapsed time between sample activation and its clinical use in order to ensure quality and biological effects of the product. This study aimed to compare three protocols for PRP achievement in order to evaluate platelet enrichment ability and method reproducibility for further use in clinical investigations regarding PRP therapeutic properties. Materials, Methods & Results: New Zealand higid rabbits whole blood was collected in tubes containing sodium citrate. Samples were obtained through exsanguination, via abdominal aortic puncture, and separated in four aliquots designed for PRP processing and basal platelet count. The count was conducted at the time blood was collected and after every concentration protocol. Methods were tested in triplicates, and three different individuals repeated each technique for three times, reaching 27 repetitions. Selected methodologies consisted in two c

O plasma rico em plaquetas derivado de sangue autólogo é definido como um volume de plasma com uma concentração plaquetária acima dos níveis fisiológicos. É uma fonte autógena e de baixo custo de fatores de crescimento (FC). FC são moléculas bioativas fundamentais no reparo e regeneração de diversos tecidos, capazes de estimular a mitogênese, angiogênese, quimiotaxia, proliferação e diferenciação celular. Entre os fatores liberados pelas plaquetas destacam-se: Fator de Crescimento Derivado de Plaquetas (PDGF), Fator de Crescimento Transformador Beta (TGF- ), Fator de Crescimento Endotelial Vascular (VEGF) e Fator de Crescimento Epitelial (EGF). [...]

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Background: Colitis murine models have become essential tools to investigate the molecular and cellular mechanisms that lead to inflammatory bowel disease (IBD), such as ulcerative colitis (UC). DSS-induced colitis model faithfully reproduces many of the clinical presentation and immunological disturbances observed in UC. Notwithstanding mice can show differential susceptibilities and responsiveness to dextran sodium sulfate (DSS), and varying DSS concentration and molecular weights appear to be associated with the severity of inflammation. The aim of this study was to analyze the features of mice induced colitis using different DSS concentrations and molecular weights. Materials, Methods and Results: C57BL/6 mice received 2% of high molecular weight DSS (36 000 - 50 000) in drinking water (HDSS2%) or 5% of the same molecular weight (HDSS5%); other group received 5% of low molecular weight DSS (10 000) (LDSS5%). During the 7 days of DSS administration, animals were observed for weight loss, stool consistency and presence of blood feces to determine the disease activity index (DAI). On day 8, colons were removed, measured and weighed for indirect assessment of inflammation. The tissue samples were processed for histological analysis and blood samples were collected for hematological analysis. Our results demonstrated that HDSS5% group began to show significant clinical signs sta

Background: Colitis murine models have become essential tools to investigate the molecular and cellular mechanisms that lead to inflammatory bowel disease (IBD), such as ulcerative colitis (UC). DSS-induced colitis model faithfully reproduces many of the clinical presentation and immunological disturbances observed in UC. Notwithstanding mice can show differential susceptibilities and responsiveness to dextran sodium sulfate (DSS), and varying DSS concentration and molecular weights appear to be associated with the severity of inflammation. The aim of this study was to analyze the features of mice induced colitis using different DSS concentrations and molecular weights. Materials, Methods and Results: C57BL/6 mice received 2% of high molecular weight DSS (36 000 - 50 000) in drinking water (HDSS2%) or 5% of the same molecular weight (HDSS5%); other group received 5% of low molecular weight DSS (10 000) (LDSS5%). During the 7 days of DSS administration, animals were observed for weight loss, stool consistency and presence of blood feces to determine the disease activity index (DAI). On day 8, colons were removed, measured and weighed for indirect assessment of inflammation. The tissue samples were processed for histological analysis and blood samples were collected for hematological analysis. Our results demonstrated that HDSS5% group began to show significant clinical signs sta