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1.
Proc Natl Acad Sci U S A ; 120(26): e2306318120, 2023 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-37307435

RESUMO

Histidine-rich protein II (HRPII) is secreted by Plasmodium falciparum during the blood stage of malaria infection. High plasma levels of HRPII are associated with cerebral malaria, a severe and highly fatal complication of malaria. HRPII has been shown to induce vascular leakage, the hallmark of cerebral malaria, in blood-brain barrier (BBB) and animal models. We have discovered an important mechanism for BBB disruption that is driven by unique features of HRPII. By characterizing serum from infected patients and HRPII produced by P. falciparum parasites in culture, we found that HRPII exists in large multimeric particles of 14 polypeptides that are richly laden with up to 700 hemes per particle. Heme loading of HRPII is required for efficient binding and internalization via caveolin-mediated endocytosis in hCMEC/D3 cerebral microvascular endothelial cells. Upon acidification of endolysosomes, two-thirds of the hemes are released from acid-labile binding sites and metabolized by heme oxygenase 1, generating ferric iron and reactive oxygen species. Subsequent activation of the NLRP3 inflammasome and IL-1ß secretion resulted in endothelial leakage. Inhibition of these pathways with heme sequestration, iron chelation, or anti-inflammatory drugs protected the integrity of the BBB culture model from HRPII:heme. Increased cerebral vascular permeability was seen after injection of young mice with heme-loaded HRPII (HRPII:heme) but not with heme-depleted HRPII. We propose that during severe malaria infection, HRPII:heme nanoparticles in the bloodstream deliver an overwhelming iron load to endothelial cells to cause vascular inflammation and edema. Disrupting this process is an opportunity for targeted adjunctive therapies to reduce the morbidity and mortality of cerebral malaria.


Assuntos
Hemeproteínas , Malária Cerebral , Malária Falciparum , Animais , Camundongos , Histidina , Células Endoteliais , Inflamação , Heme , Ferro
2.
Nutrients ; 15(6)2023 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-36986188

RESUMO

The existing literature indicates that Globularia alypum L. (GA) influences inflammation and oxidative stress modulation in rats and in vitro. The present study aims to investigate the effects of this plant in patients with ulcerative colitis (UC) and normal controls. In our experiments, we pretreated colon biopsies from 46 UC patients and normal controls with GA leaves aqueous extract (GAAE) used at two concentrations (50 and 100 µg/mL) for 3 h, followed by Lipopolysaccharides (from Escherichia coli) stimulation. We analyzed the effects on inflammation by studying the cyclo-oxygenase-2, the intercellular adhesion molecule-1, the nuclear factor kappa B, and p38 mitogen-activated protein kinase expression. Moreover, we assessed the levels of interleukin 6, the superoxide dismutase activity, and nitric oxide release in the supernatant of cultures. Our data showed that GAAE influences UC patients and normal controls for most studied markers and enzymes. These results acknowledge, with some scientific evidence, the traditional belief in the anti-inflammatory properties of GA and represent the first demonstration of its effect in a human in vitro model of inflammatory conditions.


Assuntos
Colite Ulcerativa , Humanos , Ratos , Animais , Colite Ulcerativa/metabolismo , Colo/metabolismo , NF-kappa B/metabolismo , Biópsia , Inflamação/metabolismo
3.
Cancers (Basel) ; 12(8)2020 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-32824440

RESUMO

Trabectedin (ET743) and lurbinectedin (PM01183) limit the production of inflammatory cytokines that are elevated during cancer cachexia. Mice carrying C26 colon adenocarcinoma display cachexia (i.e., premature death and body wasting with muscle, fat and cardiac tissue depletion), high levels of inflammatory cytokines and subsequent splenomegaly. We tested whether such drugs protected these mice from cachexia. Ten-week-old mice were inoculated with C26 cells and three days later randomized to receive intravenously vehicle or 0.05 mg/kg ET743 or 0.07 mg/kg PM01183, three times a week for three weeks. ET743 or PM01183 extended the lifespan of C26-mice by 30% or 85%, respectively, without affecting tumor growth or food intake. Within 13 days from C26 implant, both drugs did not protect fat, muscle and heart from cachexia. Since PM01183 extended the animal survival more than ET743, we analyzed PM01183 further. In tibialis anterior of C26-mice, but not in atrophying myotubes, PM01183 restrained the NF-κB/PAX7/myogenin axis, possibly reducing the pro-inflammatory milieu, and failed to limit the C/EBPß/atrogin-1 axis. Inflammation-mediated splenomegaly of C26-mice was inhibited by PM01183 for as long as the treatment lasted, without reducing IL-6, M-CSF or IL-1ß in plasma. ET743 and PM01183 extend the survival of C26-bearing mice unchanging tumor growth or cachexia but possibly restrain muscle-related inflammation and C26-induced splenomegaly.

4.
Cancer Res ; 80(16): 3319-3330, 2020 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-32561530

RESUMO

The presence of immunosuppressive macrophages that become activated in the tumor microenvironment constitutes a major factor responsible for tumor growth and malignancy. In line with this knowledge, we report here that macrophage proliferation is a significant feature of advanced stages of cancer. Moreover, we have found that a high proportion of proliferating macrophages in human tumors express ERK5. ERK5 was required for supporting the proliferation of macrophages in tumor grafts in mice. Furthermore, myeloid ERK5 deficiency negatively impacted the proliferation of both resident and infiltrated macrophages in metastatic lung nodules. ERK5 maintained the capacity of macrophages to proliferate by suppressing p21 expression to halt their differentiation program. Collectively, these data provide insight into the mechanism underpinning macrophage proliferation to support malignant tumor development, thereby strengthening the value of ERK5-targeted therapies to restore antitumor immunity through the blockade of protumorigenic macrophage activation. SIGNIFICANCE: These findings offer a new rationale for anti-ERK5 therapy to improve cancer patient outcomes by blocking the proliferative activity of tumor macrophages.


Assuntos
Proliferação de Células , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Proteína Quinase 7 Ativada por Mitógeno/metabolismo , Neoplasias/metabolismo , Neoplasias/patologia , Macrófagos Associados a Tumor/metabolismo , Animais , Diferenciação Celular , Humanos , Antígeno Ki-67/análise , Melanoma/secundário , Camundongos , Camundongos Endogâmicos C57BL , Proteína Quinase 7 Ativada por Mitógeno/antagonistas & inibidores , Proteína Quinase 7 Ativada por Mitógeno/deficiência , Macrófagos Associados a Tumor/citologia
5.
Life Sci ; 255: 117843, 2020 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-32464123

RESUMO

Metabolic diseases, such as obesity and type 2 diabetes, are known risk factors for cardiovascular (CV) diseases. Thus, patients with those comorbidities could be at increased risk of experiencing cardiotoxicity related to treatment with Anthracyclines and the other new generation targeted anticancer drugs. However, investigations addressing the mechanisms underlying the development of CV complications and poor outcome in such cohort of patients are still few and controversial. Given the importance of a personalized approach against chemotherapy-induced cardiomyopathy, this review summarizes our current knowledge on the pathophysiology of chemotherapy-induced cardiomyopathy and its association with obesity and type 2 diabetes. Along with clinical evidences, future perspectives of preclinical research around this field and its role in addressing important open questions, including the development of more proactive strategies for prevention, and treatment of cardiotoxicity during and after chemotherapy in the presence of metabolic diseases, is also presented.


Assuntos
Antineoplásicos/efeitos adversos , Cardiotoxicidade/etiologia , Doenças Metabólicas/complicações , Animais , Antineoplásicos/administração & dosagem , Cardiotoxicidade/fisiopatologia , Doenças Cardiovasculares/induzido quimicamente , Doenças Cardiovasculares/fisiopatologia , Diabetes Mellitus Tipo 2/complicações , Humanos , Neoplasias/tratamento farmacológico , Obesidade/complicações , Fatores de Risco
6.
J Am Coll Nutr ; 38(5): 433-440, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30794064

RESUMO

Objective: Celiac disease is an immune-mediated disease of the intestine triggered by gluten. Gluten elicits, in genetically susceptible individuals, cytokine responses that are then transmitted to the immunocompetent cells. Vegetables and fruit have anti-inflammatory and antioxidant properties with a protective effect on intestinal epithelium. Kiwifruit is known to have beneficial effects on the intestinal tissues, and it is the only plant food containing the peptide kissper, with anti-inflammatory properties. The aim of this study was the evaluation of the kissper effect on the gluten-induced inflammation in celiac disease. Methods: We used an in vitro model of intestinal culture explant from celiac disease patients and non-celiac disease patients, cultured for 24 hours with the toxic gliadin peptide P31-43 and kissper preincubation. Results: Our data showed HLA-DR and TG2 reduction in the celiac disease mucosa pretreated with kissper, as well as a reduction of COX-2 in two patients. No differences we observed for the TGF-b1 and IL-15 levels in supernatants upon kissper pretreatment. Conclusions: The preliminary results suggest that kissper has a potential anti-inflammatory role in celiac disease.


Assuntos
Actinidia , Anti-Inflamatórios/farmacologia , Doença Celíaca/metabolismo , Frutas , Peptídeos/farmacologia , Proteínas de Plantas/farmacologia , Doença Celíaca/terapia , Gliadina/efeitos adversos , Glutens/efeitos adversos , Humanos , Mucosa Intestinal/efeitos dos fármacos , Fragmentos de Peptídeos/efeitos adversos , Transdução de Sinais/efeitos dos fármacos
7.
Circ Res ; 124(8): 1214-1227, 2019 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-30686120

RESUMO

RATIONALE: The heart contains abundant interstitial and perivascular fibroblasts. Traditional views suggest that, under conditions of mechanical stress, cytokines, growth factors, and neurohumoral mediators stimulate fibroblast activation, inducing ECM (extracellular matrix) protein synthesis and promoting fibrosis and diastolic dysfunction. Members of the TGF (transforming growth factor)-ß family are upregulated and activated in the remodeling myocardium and modulate phenotype and function of all myocardial cell types through activation of intracellular effector molecules, the Smads (small mothers against decapentaplegic), and through Smad-independent pathways. OBJECTIVES: To examine the role of fibroblast-specific TGF-ß/Smad3 signaling in the remodeling pressure-overloaded myocardium. METHODS AND RESULTS: We examined the effects of cell-specific Smad3 loss in activated periostin-expressing myofibroblasts using a mouse model of cardiac pressure overload, induced through transverse aortic constriction. Surprisingly, FS3KO (myofibroblast-specific Smad3 knockout) mice exhibited accelerated systolic dysfunction after pressure overload, evidenced by an early 40% reduction in ejection fraction after 7 days of transverse aortic constriction. Accelerated systolic dysfunction in pressure-overloaded FS3KO mice was associated with accentuated matrix degradation and generation of collagen-derived matrikines, accompanied by cardiomyocyte myofibrillar loss and apoptosis, and by enhanced macrophage-driven inflammation. In vitro, TGF-ß1, TGF-ß2, and TGF-ß3 stimulated a Smad3-dependent matrix-preserving phenotype in cardiac fibroblasts, suppressing MMP (matrix metalloproteinase)-3 and MMP-8 synthesis and inducing TIMP (tissue inhibitor of metalloproteinases)-1. In vivo, administration of an MMP-8 inhibitor attenuated early systolic dysfunction in pressure-overloaded FS3KO mice, suggesting that the protective effects of activated cardiac myofibroblasts in the pressure-overloaded myocardium are, at least in part, because of suppression of MMPs and activation of a matrix-preserving program. MMP-8 stimulation induces a proinflammatory phenotype in isolated macrophages. CONCLUSIONS: In the pressure-overloaded myocardium, TGF-ß/Smad3-activated cardiac fibroblasts play an important protective role, preserving the ECM network, suppressing macrophage-driven inflammation, and attenuating cardiomyocyte injury. The protective actions of the myofibroblasts are mediated, at least in part, through Smad-dependent suppression of matrix-degrading proteases.


Assuntos
Proteínas da Matriz Extracelular/metabolismo , Miofibroblastos/metabolismo , Proteína Smad3/metabolismo , Estresse Mecânico , Remodelação Ventricular , Animais , Moléculas de Adesão Celular/metabolismo , Metaloproteinase 8 da Matriz/metabolismo , Inibidores de Metaloproteinases de Matriz/farmacologia , Camundongos , Camundongos Knockout , Pressão , Proteína Smad3/genética , Volume Sistólico , Inibidor Tecidual de Metaloproteinase-1/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Fator de Crescimento Transformador beta2/metabolismo , Fator de Crescimento Transformador beta3/metabolismo
8.
PLoS Pathog ; 14(5): e1007031, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29768491

RESUMO

Parasite egress from infected erythrocytes and invasion of new red blood cells are essential processes for the exponential asexual replication of the malaria parasite. These two tightly coordinated events take place in less than a minute and are in part regulated and mediated by proteases. Dipeptidyl aminopeptidases (DPAPs) are papain-fold cysteine proteases that cleave dipeptides from the N-terminus of protein substrates. DPAP3 was previously suggested to play an essential role in parasite egress. However, little is known about its enzymatic activity, intracellular localization, or biological function. In this study, we recombinantly expressed DPAP3 and demonstrate that it has indeed dipeptidyl aminopeptidase activity, but contrary to previously studied DPAPs, removal of its internal prodomain is not required for activation. By combining super resolution microscopy, time-lapse fluorescence microscopy, and immunoelectron microscopy, we show that Plasmodium falciparum DPAP3 localizes to apical organelles that are closely associated with the neck of the rhoptries, and from which DPAP3 is secreted immediately before parasite egress. Using a conditional knockout approach coupled to complementation studies with wild type or mutant DPAP3, we show that DPAP3 activity is important for parasite proliferation and critical for efficient red blood cell invasion. We also demonstrate that DPAP3 does not play a role in parasite egress, and that the block in egress phenotype previously reported for DPAP3 inhibitors is due to off target or toxicity effects. Finally, using a flow cytometry assay to differentiate intracellular parasites from extracellular parasites attached to the erythrocyte surface, we show that DPAP3 is involved in the initial attachment of parasites to the red blood cell surface. Overall, this study establishes the presence of a DPAP3-dependent invasion pathway in malaria parasites.


Assuntos
Dipeptidil Peptidases e Tripeptidil Peptidases/metabolismo , Malária Falciparum/parasitologia , Plasmodium falciparum/enzimologia , Animais , Cisteína Proteases/metabolismo , Eritrócitos/microbiologia , Eritrócitos/parasitologia , Interações Hospedeiro-Parasita , Malária Falciparum/metabolismo , Malária Falciparum/patologia , Merozoítos/metabolismo , Merozoítos/fisiologia , Organelas/metabolismo , Peptídeo Hidrolases/metabolismo , Plasmodium falciparum/genética , Plasmodium falciparum/metabolismo , Plasmodium falciparum/patogenicidade , Proteólise , Proteínas de Protozoários/metabolismo
9.
Proc Natl Acad Sci U S A ; 115(12): E2801-E2810, 2018 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-29507229

RESUMO

Owing to the prevalence of tumor-associated macrophages (TAMs) in cancer and their unique influence upon disease progression and malignancy, macrophage-targeted interventions have attracted notable attention in cancer immunotherapy. However, tractable targets to reduce TAM activities remain very few and far between because the signaling mechanisms underpinning protumor macrophage phenotypes are largely unknown. Here, we have investigated the role of the extracellular-regulated protein kinase 5 (ERK5) as a determinant of macrophage polarity. We report that the growth of carcinoma grafts was halted in myeloid ERK5-deficient mice. Coincidentally, targeting ERK5 in macrophages induced a transcriptional switch in favor of proinflammatory mediators. Further molecular analyses demonstrated that activation of the signal transducer and activator of transcription 3 (STAT3) via Tyr705 phosphorylation was impaired in erk5-deleted TAMs. Our study thus suggests that blocking ERK5 constitutes a treatment strategy to reprogram macrophages toward an antitumor state by inhibiting STAT3-induced gene expression.


Assuntos
Macrófagos/metabolismo , Proteína Quinase 7 Ativada por Mitógeno/metabolismo , Neoplasias/metabolismo , Neoplasias/patologia , Fator de Transcrição STAT3/metabolismo , Animais , Antígenos CD/metabolismo , Antígenos de Diferenciação Mielomonocítica/metabolismo , Polaridade Celular , Humanos , Macrófagos/patologia , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Proteína Quinase 7 Ativada por Mitógeno/genética , Fosforilação , Receptores de Superfície Celular/metabolismo , Fator de Transcrição STAT3/genética , Tirosina/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
10.
Bioorg Med Chem Lett ; 28(8): 1292-1297, 2018 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-29567345

RESUMO

Inhibitors of the enzyme NQO2 (NRH: quinone oxidoreductase 2) are of potential use in cancer chemotherapy and malaria. We have previously reported that non-symmetrical furan amidines are potent inhibitors of NQO2 and here novel analogues are evaluated. The furan ring has been changed to other heterocycles (imidazole, N-methylimidazole, oxazole, thiophene) and the amidine group has been replaced with imidate, reversed amidine, N-arylamide and amidoxime to probe NQO2 activity, improve solubility and decrease basicity of the lead furan amidine. All compounds were fully characterised spectroscopically and the structure of the unexpected product N-hydroxy-4-(5-methyl-4-phenylfuran-2-yl)benzamidine was established by X-ray crystallography. The analogues were evaluated for inhibition of NQO2, which showed lower activity than the lead furan amidine. The observed structure-activity relationship for the furan-amidine series with NQO2 was rationalized by preliminary molecular docking and binding mode analysis. In addition, the oxazole-amidine analogue inhibited the growth of Plasmodium falciparum with an IC50 value of 0.3 µM.


Assuntos
Amidinas/farmacologia , Inibidores Enzimáticos/farmacologia , Furanos/farmacologia , Quinona Redutases/antagonistas & inibidores , Amidinas/síntese química , Amidinas/química , Antimaláricos/síntese química , Antimaláricos/química , Antimaláricos/farmacologia , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Furanos/síntese química , Furanos/química , Imidazóis/síntese química , Imidazóis/química , Imidazóis/farmacologia , Estrutura Molecular , Oxazóis/síntese química , Oxazóis/química , Oxazóis/farmacologia , Oximas/síntese química , Oximas/química , Oximas/farmacologia , Plasmodium falciparum/efeitos dos fármacos , Relação Estrutura-Atividade , Tiofenos/síntese química , Tiofenos/química , Tiofenos/farmacologia
11.
Bladder Cancer ; 4(1): 41-48, 2018 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-29430506

RESUMO

BACKGROUND: TERT promotor mutations are present in >75% of bladder tumours; these mutations are also detectable in urine. Previous studies have used urinary pellet DNA, and semi-quantitative methods unsuitable for detecting very low mutant allele frequencies. OBJECTIVE: In this proof-of-principle study we use ddPCR to count the DNA molecules with wt and mutant TERT sequences in urinary cfDNA from patients whose bladder cancers harbour TERT mutations. METHODS: Urinary cfDNA prepared from the urine from 104 bladder cancer patients was analysed. We determined the mutant allele frequency across stages and grades of disease, analysed concordance between cfDNA and tumour DNA, compared cfDNA with pellet DNA, and analysed the quantity and size distribution of cfDNA. RESULTS: In 71 of 77 patients with a 228 G>A/T mutant tumour, the mutation was also detected in urinary cfDNA by ddPCR; all 6 "false negatives" were low grade pTa tumours. Overall concordance between tissue and cfDNA mutation status was 92%, and 100% was achieved for high grade disease. Median mutant allele frequencies in urinary cfDNA were 3.4, 13.4 and 32.1% in grade 1, 2 and 3 disease. The 228 G>A/T mutation was not detected in urinary cfDNA in 26 out of 27 mutation-negative patients (96% specificity). CONCLUSIONS: Concordance between tumour DNA and urinary cfDNA is high, and TERT 228 G>A/T ddPCR may prove useful for monitoring patients that harbour this mutation. Mutant allele frequencies in cfDNA are often high, but assays capable of detecting very low mutant allele frequencies will be required to achieve high sensitivity in low grade disease.

12.
Circulation ; 137(7): 707-724, 2018 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-29229611

RESUMO

BACKGROUND: Transforming growth factor-ßs regulate a wide range of cellular responses by activating Smad-dependent and Smad-independent cascades. In the infarcted heart, Smad3 signaling is activated in both cardiomyocytes and interstitial cells. We hypothesized that cell-specific actions of Smad3 regulate repair and remodeling in the infarcted myocardium. METHODS: To dissect cell-specific Smad3 actions in myocardial infarction, we generated mice with Smad3 loss in activated fibroblasts or cardiomyocytes. Cardiac function was assessed after reperfused or nonreperfused infarction using echocardiography. The effects of cell-specific Smad3 loss on the infarcted heart were studied using histological studies, assessment of protein, and gene expression levels. In vitro, we studied Smad-dependent and Smad-independent actions in isolated cardiac fibroblasts. RESULTS: Mice with fibroblast-specific Smad3 loss had accentuated adverse remodeling after reperfused infarction and exhibited an increased incidence of late rupture after nonreperfused infarction. The consequences of fibroblast-specific Smad3 loss were not a result of effects on acute infarct size but were associated with unrestrained fibroblast proliferation, impaired scar remodeling, reduced fibroblast-derived collagen synthesis, and perturbed alignment of myofibroblast arrays in the infarct. Polarized light microscopy in Sirius red-stained sections demonstrated that the changes in fibroblast morphology were associated with perturbed organization of the collagenous matrix in the infarcted area. In contrast, α-smooth muscle actin expression by infarct myofibroblasts was not affected by Smad3 loss. Smad3 critically regulated fibroblast function, activating integrin-mediated nicotinamide adenine dinucleotide phosphate (NADPH) oxidase-2 (NOX-2) expression. Smad3 loss in cardiomyocytes attenuated remodeling and dysfunction after infarction. Cardiomyocyte-specific Smad3 loss did not affect acute infarct size but was associated with attenuated cardiomyocyte apoptosis in the remodeling myocardium, accompanied by decreased myocardial NOX-2 levels, reduced nitrosative stress, and lower matrix metalloproteinase-2 expression. CONCLUSIONS: In healing myocardial infarction, myofibroblast- and cardiomyocyte-specific activation of Smad3 has contrasting functional outcomes that may involve activation of an integrin/reactive oxygen axis.


Assuntos
Fibroblastos/metabolismo , Infarto do Miocárdio/metabolismo , Miócitos Cardíacos/metabolismo , Transdução de Sinais , Proteína Smad3/metabolismo , Animais , Fibroblastos/patologia , Integrinas/genética , Integrinas/metabolismo , Metaloproteinase 2 da Matriz/genética , Metaloproteinase 2 da Matriz/metabolismo , Camundongos , Camundongos Knockout , Infarto do Miocárdio/genética , Infarto do Miocárdio/patologia , Infarto do Miocárdio/fisiopatologia , Miócitos Cardíacos/patologia , NADPH Oxidase 2/genética , NADPH Oxidase 2/metabolismo , Oxigênio/metabolismo , Proteína Smad3/genética
13.
Gut ; 66(12): 2080-2086, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28893865

RESUMO

OBJECTIVES: Counting intraepithelial lymphocytes (IEL) is central to the histological diagnosis of coeliac disease (CD), but no definitive 'normal' IEL range has ever been published. In this multicentre study, receiver operating characteristic (ROC) curve analysis was used to determine the optimal cut-off between normal and CD (Marsh III lesion) duodenal mucosa, based on IEL counts on >400 mucosal biopsy specimens. DESIGN: The study was designed at the International Meeting on Digestive Pathology, Bucharest 2015. Investigators from 19 centres, eight countries of three continents, recruited 198 patients with Marsh III histology and 203 controls and used one agreed protocol to count IEL/100 enterocytes in well-oriented duodenal biopsies. Demographic and serological data were also collected. RESULTS: The mean ages of CD and control groups were 45.5 (neonate to 82) and 38.3 (2-88) years. Mean IEL count was 54±18/100 enterocytes in CD and 13±8 in normal controls (p=0.0001). ROC analysis indicated an optimal cut-off point of 25 IEL/100 enterocytes, with 99% sensitivity, 92% specificity and 99.5% area under the curve. Other cut-offs between 20 and 40 IEL were less discriminatory. Additionally, there was a sufficiently high number of biopsies to explore IEL counts across the subclassification of the Marsh III lesion. CONCLUSION: Our ROC curve analyses demonstrate that for Marsh III lesions, a cut-off of 25 IEL/100 enterocytes optimises discrimination between normal control and CD biopsies. No differences in IEL counts were found between Marsh III a, b and c lesions. There was an indication of a continuously graded dose-response by IEL to environmental (gluten) antigenic influence.


Assuntos
Doença Celíaca/imunologia , Mucosa Intestinal/imunologia , Linfócitos/imunologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia , Estudos de Casos e Controles , Doença Celíaca/diagnóstico , Criança , Pré-Escolar , Diagnóstico Diferencial , Feminino , Humanos , Lactente , Recém-Nascido , Contagem de Linfócitos , Masculino , Pessoa de Meia-Idade , Prognóstico , Curva ROC
14.
Int J Pharm ; 525(2): 377-387, 2017 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-28189855

RESUMO

Tailored developed nanoliposomes loaded with a siRNA against the transcription factor E2F1 (siE2F1), were produced and delivered to human colorectal adenocarcinoma cell lines and to intestinal human biopsies. siE2F1 loaded nanoliposomes were produced through a dedicated ultrasound assisted technique producing particles with about 40nm size (Small Unilamellar Vesicles, SUVs) and 100% siRNA encapsulation efficiency. Compared to other production methods, the one proposed here can easily produce particles in the nanometric scale by suitable ultrasonic duty cycle treatments. Furthermore, SUVs have a high degree of size homogeneity, a relevant feature for uniform delivery behaviour. siE2F1-loaded SUVs demonstrated a very low cytotoxicity in cells when compared to a commercial transfection agent. Moreover, SUVs loaded with siE2F1 were effective in the down regulation of the target in cultured colon carcinoma cells and in the consequent reduction of cell growth. Finally, a remarkable uptake and target silencing efficiencies were observed in cultured human biopsy of colonic mucosa. In conclusion, whereas further studies in more complex models are required, the siE2F1-SUVs generated have the potential to contribute to the development of novel effective inflammatory bowel diseases-associated colorectal cancer therapies for a future personalized medicine.


Assuntos
Adenocarcinoma/genética , Neoplasias Colorretais/genética , Fator de Transcrição E2F1/genética , Inativação Gênica , RNA Interferente Pequeno/administração & dosagem , Adenocarcinoma/terapia , Linhagem Celular Tumoral , Proliferação de Células , Neoplasias Colorretais/terapia , Humanos , Lipossomos/química , Nanopartículas/química , Transfecção , Ultrassonografia
15.
Curr Drug Deliv ; 14(2): 246-252, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-27174173

RESUMO

BACKGROUND: Short interfering RNAs (siRNAs) are double-stranded RNA molecules able to specifically targeting genes products responsible for human diseases. Cyclin D1 (CyD1) is a cell cycleregulatory molecule, up-regulated at sites of inflammation in several tissues. CyD1 is a very interesting potential target in lung and colon inflammatory diseases. OBJECTIVE: The aim of this paper was testing CyD1 expression in human lung and colon tissues after the application of an inflammatory stimulus, and verifying its gene silencing by using siRNA for CyD1 (siCyD1). METHOD: Colon and pulmonary biopsies were treated with siCyD1 by using two different transfection carriers: a) invivofectamine and b) ad hoc produced nanoliposomes. After 24 hours of incubation with nanoliposomes encapsulating siRNA or invivofectamine-CyD1siRNA, in presence or absence of ECLPS, we analysed the protein expression of CyD1 through Western-Blotting. RESULTS: After EC-LPS treatment, in both colon and pulmonary biopsies, an overexpression of CyD1was found (about 64% and 40% respectively). Invivofectamine-CyD1 siRNA reduced the expression of CyD1 approximately by 46% compared to the basal condition, and by around 65% compared to EC-LPS treated colon samples. In lung, following in vivo fectamine siRNA silencing in the presence of EC-LPS, no reduction was observed. Ad hoc nanoliposomes were able to enter colon and lung tissues, but CyD1 silencing was reported in 2 colon samples out of 4 and no efficacy was demonstrated in the only lung sample we studied. CONCLUSION: The silencing of Cyclin D1 expression in vitro "organ culture" model is possible. Our preliminary results encourage further investigations, using different siRNA concentrations delivered by nanoliposomes.


Assuntos
Ciclina D1/deficiência , Ciclina D1/genética , Inativação Gênica , RNA Interferente Pequeno/genética , Técnicas de Cultura de Tecidos , Feminino , Humanos , Masculino
16.
Transl Med UniSa ; 17: 22-30, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30050877

RESUMO

Evidence in inflammatory bowel diseases (IBD) supports a connection between inflammation and cancer due to the alteration of the cell cycle with loss of control at the G1/S checkpoint. In this study, we analyze the expression and modulation of CyD1 and E2F1 in colon explants from Crohn's disease (CD) patients. We used ex vivo culture of colon explants from 4 CD patients and 2 healthy controls, stimulated with lipopolysaccharide from Escherichia Coli (EC-LPS). Commercial siRNAs for CyD1 and E2F1 inhibition were encapsulated in Invivofectamine® and in purposely produced nanoliposomal vectors to silencing CyD1 and E2F1 expression. Western blot analysis was used to investigate the effect of siRNA on CyD1, E2F1 and cyclooxygenase 2 (COX-2) expression. In CD patients colon explants, CyD1 and E2F1 increased after the inflammatory stimulus but siRNA silencing attenuated their expression and controlled the COX-2 expression too. These data represent a prelimiary exploration of in vitro siRNA use.

17.
Transl Med UniSa ; 17: 25-33, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30083520

RESUMO

Evidence in inflammatory bowel diseases (IBD) supports a connection between inflammation and cancer due to the alteration of the cell cycle with loss of control at the G1/S checkpoint. In this study, we analyze the expression and modulation of CyD1 and E2F1 in colon explants from Crohn's disease (CD) patients. We used ex vivo culture of colon explants from 4 CD patients and 2 healthy controls, stimulated with lipopolysaccharide from Escherichia Coli (EC-LPS). Commercial siRNAs for CyD1 and E2F1 inhibition were encapsulated in Invivofectamine® and in purposely produced nanoliposomal vectors to silencing CyD1 and E2F1 expression. Western blot analysis was used to investigate the effect of siRNA on CyD1, E2F1 and cyclooxygenase 2 (COX-2) expression. In CD patients colon explants, CyD1 and E2F1 increased after the inflammatory stimulus but siRNA silencing attenuated their expression and controlled the COX-2 expression too. These data represent a prelimiary exploration of in vitro siRNA use.

18.
Am J Gastroenterol ; 111(6): 879-90, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27045926

RESUMO

OBJECTIVES: Celiac disease (CD)-associated duodenal dysbiosis has not yet been clearly defined, and the mechanisms by which CD-associated dysbiosis could concur to CD development or exacerbation are unknown. In this study, we analyzed the duodenal microbiome of CD patients. METHODS: The microbiome was evaluated in duodenal biopsy samples of 20 adult patients with active CD, 6 CD patients on a gluten-free diet, and 15 controls by DNA sequencing of 16S ribosomal RNA libraries. Bacterial species were cultured, isolated and identified by mass spectrometry. Isolated bacterial species were used to infect CaCo-2 cells, and to stimulate normal duodenal explants and cultured human and murine dendritic cells (DCs). Inflammatory markers and cytokines were evaluated by immunofluorescence and ELISA, respectively. RESULTS: Proteobacteria was the most abundant and Firmicutes and Actinobacteria the least abundant phyla in the microbiome profiles of active CD patients. Members of the Neisseria genus (Betaproteobacteria class) were significantly more abundant in active CD patients than in the other two groups (P=0.03). Neisseria flavescens (CD-Nf) was the most abundant Neisseria species in active CD duodenum. Whole-genome sequencing of CD-Nf and control-Nf showed genetic diversity of the iron acquisition systems and of some hemoglobin-related genes. CD-Nf was able to escape the lysosomal compartment in CaCo-2 cells and to induce an inflammatory response in DCs and in ex-vivo mucosal explants. CONCLUSIONS: Marked dysbiosis and an abundance of a peculiar CD-Nf strain characterize the duodenal microbiome in active CD patients thus suggesting that the CD-associated microbiota could contribute to the many inflammatory signals in this disorder.


Assuntos
Doença Celíaca/microbiologia , Duodeno/microbiologia , Disbiose/microbiologia , Metagenômica , Neisseria/isolamento & purificação , Actinobacteria/classificação , Actinobacteria/isolamento & purificação , Adulto , Biópsia , Células CACO-2 , Dieta Livre de Glúten , Ensaio de Imunoadsorção Enzimática , Feminino , Imunofluorescência , Humanos , Itália , Masculino , Microbiota , Neisseria/classificação , Proteobactérias/classificação , Proteobactérias/isolamento & purificação
19.
Am J Pathol ; 186(5): 1114-27, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-26948424

RESUMO

The ß-galactoside-binding animal lectin galectin-3 is predominantly expressed by activated macrophages and is a promising biomarker for patients with heart failure. Galectin-3 regulates inflammatory and fibrotic responses; however, its role in cardiac remodeling remains unclear. We hypothesized that galectin-3 may be up-regulated in the pressure-overloaded myocardium and regulate hypertrophy and fibrosis. In normal mouse myocardium, galectin-3 was constitutively expressed in macrophages and was localized in atrial but not ventricular cardiomyocytes. In a mouse model of transverse aortic constriction, galectin-3 expression was markedly up-regulated in the pressure-overloaded myocardium. Early up-regulation of galectin-3 was localized in subpopulations of macrophages and myofibroblasts; however, after 7 to 28 days of transverse aortic constriction, a subset of cardiomyocytes in fibrotic areas contained large amounts of galectin-3. In vitro, cytokine stimulation suppressed galectin-3 synthesis by macrophages and cardiac fibroblasts. Correlation studies revealed that cardiomyocyte- but not macrophage-specific galectin-3 localization was associated with adverse remodeling and dysfunction. Galectin-3 knockout mice exhibited accelerated cardiac hypertrophy after 7 days of pressure overload, whereas female galectin-3 knockouts had delayed dilation after 28 days of transverse aortic constriction. However, galectin-3 loss did not affect survival, systolic and diastolic dysfunction, cardiac fibrosis, and cardiomyocyte hypertrophy in the pressure-overloaded heart. Despite its potential role as a prognostic biomarker, galectin-3 is not a critical modulator of cardiac fibrosis but may delay the hypertrophic response.


Assuntos
Cardiomegalia/fisiopatologia , Galectina 3/metabolismo , Miocárdio/metabolismo , Remodelação Ventricular/fisiologia , Animais , Biomarcadores/metabolismo , Pressão Sanguínea/fisiologia , Cardiomegalia/diagnóstico por imagem , Ecocardiografia Doppler , Fibrose Endomiocárdica/diagnóstico por imagem , Fibrose Endomiocárdica/fisiopatologia , Feminino , Interleucina-1beta/farmacologia , Macrófagos/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Miofibroblastos/metabolismo , Miofibroblastos/fisiologia , Proteína Smad3/farmacologia , Fator de Crescimento Transformador beta/farmacologia , Regulação para Cima/fisiologia , Disfunção Ventricular Esquerda/diagnóstico por imagem , Disfunção Ventricular Esquerda/fisiopatologia
20.
Eur J Med Chem ; 111: 33-45, 2016 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-26854376

RESUMO

NRH:quinone oxidoreductase 2 enzyme (NQO2) is a potential therapeutic target in cancer and neurodegenerative diseases, with roles in either chemoprevention or chemotherapy. Here we report the design, synthesis and evaluation of non-symmetrical furan-amidines and their analogues as novel selective NQO2 inhibitors with reduced adverse off-target effects, such as binding to DNA. A pathway for the synthesis of the non-symmetrical furan-amidines was established from the corresponding 1,4-diketones. The synthesized non-symmetrical furan-amidines and their analogues showed potent NQO2 inhibition activity with nano-molar IC50 values. The most active compounds were non-symmetrical furan-amidines with meta- and para-nitro substitution on the aromatic ring, with IC50 values of 15 nM. In contrast to the symmetric furan-amidines, which showed potent intercalation in the minor grooves of DNA, the synthesized non-symmetrical furan-amidines showed no affinity towards DNA, as demonstrated by DNA melting temperature experiments. In addition, Plasmodium parasites, which possess their own quinone oxidoreductase PfNDH2, were inhibited by the non-symmetrical furan-amidines, the most active possessing a para-fluoro substituent (IC50 9.6 nM). The high NQO2 inhibition activity and nanomolar antimalarial effect of some of these analogues suggest the lead compounds are worthy of further development and optimization as potential drugs for novel anti-cancer and antimalarial strategies.


Assuntos
Amidinas/farmacologia , Antimaláricos/farmacologia , Antineoplásicos/farmacologia , Furanos/farmacologia , Malária/tratamento farmacológico , Plasmodium/efeitos dos fármacos , Amidinas/síntese química , Amidinas/química , Antimaláricos/síntese química , Antimaláricos/química , Antineoplásicos/síntese química , Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Furanos/síntese química , Furanos/química , Humanos , Modelos Moleculares , Estrutura Molecular , Testes de Sensibilidade Parasitária , Relação Estrutura-Atividade
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