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1.
J Crohns Colitis ; 13(9): 1186-1200, 2019 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-31220227

RESUMEN

Intestinal fibrosis and stenosis are common complications of Crohn's disease [CD], frequently requiring surgery. Anti-inflammatory strategies can only partially prevent fibrosis; hence, anti-fibrotic therapies remain an unmet clinical need. Oxysterols are oxidised cholesterol derivatives with important roles in various biological processes. The enzyme cholesterol 25-hydroxylase [CH25H] converts cholesterol to 25-hydroxycholesterol [25-HC], which modulates immune responses and oxidative stress. In human intestinal samples from CD patients, we found a strong correlation of CH25H mRNA expression with the expression of fibrosis markers. We demonstrate reduced intestinal fibrosis in mice deficient for the CH25H enzyme, using the sodium dextran sulphate [DSS]-induced chronic colitis model. Additionally, using a heterotopic transplantation model of intestinal fibrosis, we demonstrate reduced collagen deposition and lower concentrations of hydroxyproline in CH25H knockouts. In the heterotopic transplant model, CH25H was expressed in fibroblasts. Taken together, our findings indicate an involvement of oxysterol synthesis in the pathogenesis of intestinal fibrosis.


Asunto(s)
Intestinos/patología , Oxiesteroles/metabolismo , Esteroide Hidroxilasas/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Animales , Colitis/inducido químicamente , Colitis/enzimología , Enfermedad de Crohn/complicaciones , Enfermedad de Crohn/patología , Sulfato de Dextran/farmacología , Modelos Animales de Enfermedad , Femenino , Fibrosis , Humanos , Intestinos/enzimología , Intestinos/trasplante , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Persona de Mediana Edad , Esteroide Hidroxilasas/deficiencia
2.
Sci Rep ; 8(1): 15182, 2018 10 12.
Artículo en Inglés | MEDLINE | ID: mdl-30315190

RESUMEN

Intestinal fibrosis is thought to be a consequence of excessive tissue repair, and constitutes a common problem in patients with Crohn's disease (CD). While fibrosis seems to require inflammation as a prerequisite it is unclear whether the severity or persistence of inflammation influences the degree of fibrosis. Our aim was to investigate the role of sustained inflammation in fibrogenesis. For the initiation of fibrosis in vivo the models of Il10-/- spontaneous colitis, dextran sodium sulfate (DSS)-induced chronic colitis and heterotopic transplantation were used. In Il10-/- mice, we determined a positive correlation between expression of pro-inflammatory factors (Il1ß, Tnf, Ifnγ, Mcp1 and Il6). We also found a positive correlation between the expression of pro-fibrotic factors (Col3a1 Col1a1, Tgfß and αSma). In contrast, no significant correlation was determined between the expression of pro-inflammatory Tnf and pro-fibrotic αSma, Col1a1, Col3a1, collagen layer thickness and the hydroxyproline (HYP) content. Results from the DSS-induced chronic colitis model confirmed this finding. In the transplantation model for intestinal fibrosis a pronounced increase in Mcp1, inos and Il6 in Il10-/- as compared to WT grafts was observed, indicating more severe inflammation in Il10-/- grafts. However, the increase of collagen over time was virtually identical in both Il10-/- and WT grafts. Severity of inflammation during onset of fibrogenesis did not correlate with collagen deposition. Although inflammation might be a pre-requisite for the initiation of fibrosis our data suggest that it has a minor impact on the progression of fibrosis. Our results suggest that development of fibrosis and inflammation may be disconnected. This may be important for explaining the inefficacy of anti-inflammatory treatments agents in most cases of fibrotic inflammatory bowel diseases (IBD).


Asunto(s)
Fibrosis/patología , Inflamación/patología , Intestinos/patología , Animales , Colitis/metabolismo , Colitis/patología , Colágeno/metabolismo , Colon/metabolismo , Colon/patología , Enfermedad de Crohn/metabolismo , Enfermedad de Crohn/patología , Modelos Animales de Enfermedad , Fibrosis/metabolismo , Hidroxiprolina/metabolismo , Inflamación/metabolismo , Enfermedades Inflamatorias del Intestino/metabolismo , Enfermedades Inflamatorias del Intestino/patología , Interleucina-10/metabolismo , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patología , Masculino , Ratones , Ratones Endogámicos C57BL
3.
Clin Exp Immunol ; 193(3): 346-360, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-29745420

RESUMEN

In inflammatory bowel disease (IBD), inflammation is sustained by an exaggerated response of lymphocytes. This results from enhanced expression of anti-apoptotic B cell lymphoma (BCL-2) and BCL-XL associated with a diminished turnover. Azathioprine (AZA) directly targets BCL-2 family-mediated apoptosis. We investigated whether the BCL-2 family expression pattern could be used to predict treatment response to AZA and determined whether BCL-2 inhibitor A-1211212 effectively diminishes lymphocytes and ameliorates inflammation in a model of colitis. BCL-2 family expression pattern was determined by next-generation sequencing (NGS). BCL-2 inhibitor was administered orally to Il10-/- mice. Haematological analyses were performed with an ADVIA 2120 and changes in immune cells were investigated using quantitative polymerase chain reaction (qPCR) and fluorescence activated cell sorter (FACS). We determined similar expression levels of BCL-2 family members in patients with remission and patients refractory to treatment, showing that BCL-2 family expression can not predict AZA treatment response. Expression was not correlated with the modified Truelove and Witts activity index (MTWAI). BCL-2 inhibitor initiated cell death in T cells from patients refractory to AZA and reduced lymphocyte count in Il10-/- mice. FACS revealed diminished CD8+ T cells upon BCL-2 inhibitor in Il10-/- mice without influencing platelets. Tnf, Il1ß, IfnƔ and Mcp-1 were decreased upon BCL-2 inhibitor. A-1211212 positively altered the colonic mucosa and ameliorated inflammation in mice. Pro-apoptotic BCL-2 inhibitor A-1211212 diminishes lymphocytes and ameliorates colitis in Il10-/- mice without inducing thrombocytopenia. BCL-2 inhibition could be a new therapy option for patients refractory to AZA.


Asunto(s)
Azatioprina/uso terapéutico , Colitis/tratamiento farmacológico , Enfermedades Inflamatorias del Intestino/tratamiento farmacológico , Linfocitos/efectos de los fármacos , Proteínas Proto-Oncogénicas c-bcl-2/genética , Animales , Apoptosis , Células Cultivadas , Colitis/diagnóstico , Colitis/genética , Citocinas/metabolismo , Modelos Animales de Enfermedad , Humanos , Mediadores de Inflamación/metabolismo , Enfermedades Inflamatorias del Intestino/diagnóstico , Enfermedades Inflamatorias del Intestino/genética , Interleucina-10/genética , Linfocitos/fisiología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Pronóstico , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Resultado del Tratamiento
4.
Nanoscale ; 7(42): 17938-46, 2015 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-26463479

RESUMEN

Trinucleotide repeat expansions (like (CGG)n) of chromatin in the genome of cell nuclei can cause neurological disorders such as for example the Fragile-X syndrome. Until now the mechanisms are not clearly understood as to how these expansions develop during cell proliferation. Therefore in situ investigations of chromatin structures on the nanoscale are required to better understand supra-molecular mechanisms on the single cell level. By super-resolution localization microscopy (Spectral Position Determination Microscopy; SPDM) in combination with nano-probing using COMBO-FISH (COMBinatorial Oligonucleotide FISH), novel insights into the nano-architecture of the genome will become possible. The native spatial structure of trinucleotide repeat expansion genome regions was analysed and optical sequencing of repetitive units was performed within 3D-conserved nuclei using SPDM after COMBO-FISH. We analysed a (CGG)n-expansion region inside the 5' untranslated region of the FMR1 gene. The number of CGG repeats for a full mutation causing the Fragile-X syndrome was found and also verified by Southern blot. The FMR1 promotor region was similarly condensed like a centromeric region whereas the arrangement of the probes labelling the expansion region seemed to indicate a loop-like nano-structure. These results for the first time demonstrate that in situ chromatin structure measurements on the nanoscale are feasible. Due to further methodological progress it will become possible to estimate the state of trinucleotide repeat mutations in detail and to determine the associated chromatin strand structural changes on the single cell level. In general, the application of the described approach to any genome region will lead to new insights into genome nano-architecture and open new avenues for understanding mechanisms and their relevance in the development of heredity diseases.


Asunto(s)
Hibridación Fluorescente in Situ , Nanoestructuras/química , Expansión de Repetición de Trinucleótido/genética , Regiones no Traducidas 5' , Línea Celular Tumoral , Sondas de ADN/química , Sondas de ADN/metabolismo , Proteína de la Discapacidad Intelectual del Síndrome del Cromosoma X Frágil/genética , Proteína de la Discapacidad Intelectual del Síndrome del Cromosoma X Frágil/metabolismo , Síndrome del Cromosoma X Frágil/genética , Síndrome del Cromosoma X Frágil/patología , Humanos , Procesamiento de Imagen Asistido por Computador , Microscopía Confocal , Regiones Promotoras Genéticas
5.
Clin Exp Immunol ; 181(2): 343-56, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25845418

RESUMEN

Exaggerated activation of lymphocytes contributes to the pathogenesis of inflammatory bowel disease (IBD). Medical therapies are linked to the BCL-2 family-mediated apoptosis. Imbalance in BCL-2 family proteins may cause failure in therapeutic responses. We investigated the role of BCL-2 inhibitor ABT-737 for lymphocyte apoptosis in mice under inflammatory conditions. B.6129P2-interleukin (IL)-10(tm1Cgn) /J (IL-10(-/-) ) weighing 25-30 g with ongoing colitis were used. Fifty mg/kg/day ABT-737 was injected intraperitoneally (i.p.). Haematological analyses were performed with an ADVIA 2120 flow cytometer and mass cytometry with a CyTOF 2. Following i.p. administration, ABT-737 was detected in both spontaneous and acute colitis in peripheral blood (PBL) and colon tissue. Treatment led to lymphopenia. CD4(+) CD44(+) CD62L(+) central memory and CD8(+) , CD44(+) CD62L(-) central memory T cells were decreased in PBL upon ABT-737 compared to vehicle-receiving controls. Increased apoptosis upon ABT-737 was determined in blood lymphocytes, splenocytes and Peyer's patches and was accompanied by a decrease in TNF and IL-1B. ABT-737 positively altered the colonic mucosa and ameliorated inflammation, as shown by colonoscopy, histology and colon length. A decreased BIM/BCL-2 ratio or absence of BIM in both Bim(-) (/) (-) and Il10(-) (/) (-) × Bim(-) (/) (-) impeded the protective effect of ABT-737. The BIM/BCL-2 ratio decreased with age and during the course of treatment. Thus, long-term treatment resulted in adapted TNF levels and macroscopic mucosal damage. ABT-737 was efficacious in diminishing lymphocytes and ameliorating colitis in a BIM-dependent manner. Regulation of inappropriate survival of lymphocytes by ABT-737 may provide a therapeutic strategy in IBD.


Asunto(s)
Proteínas Reguladoras de la Apoptosis/genética , Compuestos de Bifenilo/farmacología , Colitis/tratamiento farmacológico , Proteínas de la Membrana/genética , Nitrofenoles/farmacología , Proteínas Proto-Oncogénicas c-bcl-2/genética , Proteínas Proto-Oncogénicas/genética , Sulfonamidas/farmacología , Animales , Apoptosis/efectos de los fármacos , Proteínas Reguladoras de la Apoptosis/metabolismo , Proteína 11 Similar a Bcl2 , Linfocitos T CD4-Positivos/efectos de los fármacos , Linfocitos T CD4-Positivos/metabolismo , Linfocitos T CD4-Positivos/patología , Linfocitos T CD8-positivos/efectos de los fármacos , Linfocitos T CD8-positivos/metabolismo , Linfocitos T CD8-positivos/patología , Colitis/inducido químicamente , Colitis/genética , Colitis/patología , Sulfato de Dextran , Femenino , Expresión Génica , Receptores de Hialuranos/genética , Receptores de Hialuranos/metabolismo , Inyecciones Intraperitoneales , Interleucina-10/genética , Interleucina-10/metabolismo , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Selectina L/genética , Selectina L/metabolismo , Linfopenia/inducido químicamente , Linfopenia/genética , Linfopenia/patología , Proteínas de la Membrana/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Piperazinas/farmacología , Proteínas Proto-Oncogénicas/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Transducción de Señal , Factor de Necrosis Tumoral alfa/genética , Factor de Necrosis Tumoral alfa/metabolismo
6.
Histochem Cell Biol ; 142(1): 43-59, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24614971

RESUMEN

Localization microscopy approaches allowing an optical resolution down to the single-molecule level in fluorescence-labeled biostructures have already found a variety of applications in cell biology, as well as in virology. Here, we focus on some perspectives of a special localization microscopy embodiment, spectral precision distance/position determination microscopy (SPDM). SPDM permits the use of conventional fluorophores or fluorescent proteins together with standard sample preparation conditions employing an aqueous buffered milieu and typically monochromatic excitation. This allowed superresolution imaging and studies on the aggregation state of modified tobacco mosaic virus particles on the nanoscale with a single-molecule localization accuracy of better than 8 nm, using standard fluorescent dyes in the visible spectrum. To gain a better understanding of cell entry mechanisms during influenza A virus infection, SPDM was used in conjunction with algorithms for distance and cluster analyses to study changes in the distribution of virus particles themselves or in the distribution of infection-related proteins, the hepatocyte growth factor receptors, in the cell membrane on the single-molecule level. Not requiring TIRF (total internal reflection) illumination, SPDM was also applied to study the molecular arrangement of gp36.5/m164 glycoprotein (essentially associated with murine cytomegalovirus infection) in the endoplasmic reticulum and the nuclear membrane inside cells with single-molecule resolution. On the basis of the experimental evidence so far obtained, we finally discuss additional application perspectives of localization microscopy approaches for the fast detection and identification of viruses by multi-color SPDM and combinatorial oligonucleotide fluorescence in situ hybridization, as well as SPDM techniques for optimization of virus-based nanotools and biodetection devices.


Asunto(s)
Virus de la Influenza A , Microscopía Fluorescente/métodos , Virus del Mosaico del Tabaco , Virología/métodos , Algoritmos , Animales , Células COS , Línea Celular Tumoral , Chlorocebus aethiops , Colorantes Fluorescentes/análisis , Colorantes Fluorescentes/química , Humanos , Virus de la Influenza A/química , Virus de la Influenza A/aislamiento & purificación , Proteínas Luminiscentes/análisis , Proteínas Luminiscentes/química , Virus del Mosaico del Tabaco/química , Virus del Mosaico del Tabaco/aislamiento & purificación
7.
Neuroscience ; 258: 307-17, 2014 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-24262802

RESUMEN

It was the aim of the present study to investigate menstrual cycle effects on selective attention and its underlying functional cerebral networks. Twenty-one healthy, right-handed, normally cycling women were investigated by means of functional magnetic resonance imaging using a go/no-go paradigm during the menstrual, follicular and luteal phase. On the behavioral level there was a significant interaction between visual half field and cycle phase with reaction times to right-sided compared to left-sided stimuli being faster in the menstrual compared to the follicular phase. These results might argue for a more pronounced functional cerebral asymmetry toward the left hemisphere in selective attention during the menstrual phase with low estradiol and progesterone levels. Functional imaging, however, did not reveal clear-cut menstrual phase-related changes in activation pattern in parallel to these behavioral findings. A functional connectivity analysis identified differences between the menstrual and the luteal phase: During the menstrual phase, left inferior parietal cortex showed a stronger negative correlation with the right middle frontal gyrus while the left medial frontal cortex showed a stronger negative correlation with the left middle frontal gyrus. These results can serve as further evidence of a modulatory effect of steroid hormones on networks of lateralized cognitive functions not only by interhemispheric inhibition but also by affecting intrahemispheric functional connectivity.


Asunto(s)
Atención/fisiología , Corteza Cerebral/fisiología , Ciclo Menstrual/fisiología , Adolescente , Adulto , Mapeo Encefálico , Estradiol/sangre , Femenino , Lateralidad Funcional , Humanos , Imagen por Resonancia Magnética , Vías Nerviosas/fisiología , Pruebas Neuropsicológicas , Progesterona/sangre , Desempeño Psicomotor/fisiología , Análisis y Desempeño de Tareas , Adulto Joven
8.
Digestion ; 88(3): 182-92, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24193262

RESUMEN

BACKGROUND AND AIMS: Transketolase-like (TKTL) 1 is one of the key enzymes for anaerobic sugar degradation even in the presence of oxygen (aerobic glycolysis). Transketolase-dependent reactions supply malignant tumors with ribose and NADPH. Therefore, TKTL1 activity could be crucial for tumor proliferation and survival. The aim of the study was to evaluate the expression of TKTL1 in colorectal cancer (CRC) and its regulation under hypoxic conditions. METHODS: We studied TKTL1 mRNA and protein expression in CRC cell lines and human CRC biopsies by quantitative real-time PCR, Western blotting and immunohistochemistry. Regulation of TKTL1 under oxygen depletion was analyzed by cultivating cells either in a three-dimensional spheroid model or in a hypoxia incubator chamber. RESULTS: TKTL1 mRNA was heterogeneously expressed in monolayers of cells with high levels in HT-29 and SW480. TKTL1 protein was also clearly detectable in HT-29 and SW480. Hypoxia-inducible factor (HIF)-1α protein expression correlated with TKTL1 protein expression in SW480 spheroids over time. On the one hand, induction of hypoxia in T84 spheroids did not induce TKTL1; on the other hand, hypoxia by incubation at 1% O2 in a hypoxia incubator chamber clearly showed an upregulation of TKTL1. In 50% of CRC patients, TKTL1 protein expression was upregulated in tumor compared to non-tumor tissue. The immunohistochemical staining of TKTL1 in CRC patient samples resulted in 14 positive and 30 negative samples. CONCLUSIONS: TKTL1 expression correlated with HIF-1α protein expression and was induced upon hypoxic conditions which could facilitate energy supply to tumors under these circumstances.


Asunto(s)
Neoplasias Colorrectales/genética , Regulación Neoplásica de la Expresión Génica , Hipoxia/genética , ARN Mensajero/análisis , Transcetolasa/genética , Adulto , Anciano , Anciano de 80 o más Años , Western Blotting , Línea Celular Tumoral , Neoplasias Colorrectales/metabolismo , Femenino , Glucólisis , Células HT29 , Humanos , Hipoxia/metabolismo , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Reacción en Cadena en Tiempo Real de la Polimerasa , Transcetolasa/metabolismo , Regulación hacia Arriba
9.
Lab Anim ; 47(4): 274-83, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23828853

RESUMEN

An impaired intestinal epithelial barrier is thought to be a major factor in the pathogenesis of human inflammatory bowel disease (IBD). IBD is frequently investigated by inducing a damaged barrier in murine models of colitis. This can be done by feeding mice with dextran sulfate sodium (DSS) polymers in their drinking water. Refinement measures should focus on alleviating unnecessary suffering during this probably painful condition. Appropriate parameters are needed to decide when to terminate the experiments. Our aim was to investigate whether a change in burrowing behaviour is a sensitive measure of animal welfare in murine models of colitis. Acute colitis was induced in C57BL/6 mice with 2.0% DSS over nine days. The burrowing test is based on the species-typical behaviour of mice to spontaneously displace items from tubes within their home cage. As a burrowing apparatus, a water bottle (250 mL, 150 mm length, 55 mm diameter) filled with 138-142 g of pellets of the animal's diet was used. The presence of intestinal inflammation as a result of acute DSS-induced colitis was confirmed by a decrease in body weight, colon length and an increase of murine endoscopic index of colitis severity, histological score and spleen weight in the group receiving DSS as compared with the control group. An onset of intestinal inflammation correlated with a significant decrease in burrowing behaviour (P < 0.05). Altered adrenal gland histology indicated stress as a result of acute colitis. Our findings provide evidence that changes of spontaneous burrowing behaviour correlate with the onset of inflammation in acute DSS-induced colitis.


Asunto(s)
Bienestar del Animal , Conducta Animal , Estrés Fisiológico , Animales , Colitis/inducido químicamente , Colitis/patología , Colonoscopía/veterinaria , Modelos Animales de Enfermedad , Ratones , Ratones Endogámicos C57BL , Dolor
10.
Neuropsychologia ; 51(9): 1734-41, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23727572

RESUMEN

It is still a matter of debate whether functional cerebral asymmetries (FCA) of many cognitive processes are more pronounced in men than in women. Some evidence suggests that the apparent reduction in women's FCA is a result of the fluctuating levels of gonadal steroid hormones over the course of the menstrual cycle, making their FCA less static than for men. The degree of lateralization has been suggested to depend on interhemispheric communication that may be modulated by gonadal steroid hormones. Here, we employed visual-evoked EEG potentials to obtain a direct measure of interhemispheric communication during different phases of the menstrual cycle. The interhemispheric transfer time (IHTT) was estimated from the interhemispheric latency difference of the N170 component of the visual-evoked potential from either left or right visual field presentation. Nineteen right-handed women with regular menstrual cycles were tested twice, once during the menstrual phase, when progesterone and estradiol levels are low, and once during the luteal phase when progesterone and estradiol levels are high. Plasma steroid levels were determined by blood-based immunoassay at each session. It was found that IHTT, in particular from right-to-left, was generally longer during the luteal phase relative to the menstrual phase. This effect occurred as a consequence of a slowed absolute N170 latency of the indirect pathway (i.e. left hemispheric response after LVF stimulation) and, in particular, a shortened latency of the direct pathway (i.e. right hemispheric response after LVF stimulation) during the luteal phase. These results show that cycle-related effects are not restricted to modulation of processes between hemispheres but also apply to cortical interactions, especially within the right hemisphere. The findings support the view that plastic changes in the female brain occur during relatively short-term periods across the menstrual cycle.


Asunto(s)
Cerebro/fisiología , Estradiol/fisiología , Potenciales Evocados Visuales , Ciclo Menstrual , Progesterona/fisiología , Adulto , Electroencefalografía , Estradiol/sangre , Femenino , Humanos , Vías Nerviosas/fisiología , Estimulación Luminosa , Progesterona/sangre , Factores de Tiempo , Percepción Visual/fisiología
11.
Clin Exp Immunol ; 173(3): 493-501, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23668821

RESUMEN

We investigated the role of B cell lymphoma (BCL)-2-interacting mediator of cell death (Bim) for lymphocyte homeostasis in intestinal mucosa. Lymphocytes lacking Bim are refractory to apoptosis. Chronic colitis was induced in Bim-deficient mice (Bim(-/-) ) with dextran sulphate sodium (DSS). Weight loss and colonoscopic score were increased significantly in Bim(-/-) mice compared to wild-type mice. As Bim is induced for the killing of autoreactive cells we determined the role of Bim in the regulation of lymphocyte survival at mucosal sites. Upon chronic dextran sulphate sodium (DSS)-induced colitis, Bim(-/-) animals exhibited an increased infiltrate of lymphocytes into the mucosa compared to wild-type mice. The number of autoreactive T cell receptor (TCR) Vß8(+) lymphocytes was significantly higher in Bim(-/-) mice compared to wild-type controls. Impaired removal of autoreactive lymphocytes in Bim(-/-) mice upon chronic DSS-induced colitis may therefore contribute to aggravated mucosal inflammation.


Asunto(s)
Proteínas Reguladoras de la Apoptosis/deficiencia , Colitis/inmunología , Colitis/metabolismo , Linfocitos/inmunología , Linfocitos/metabolismo , Proteínas de la Membrana/deficiencia , Proteínas Proto-Oncogénicas/deficiencia , Receptores de Antígenos de Linfocitos T alfa-beta/metabolismo , Animales , Proteínas Reguladoras de la Apoptosis/genética , Autoinmunidad/genética , Proteína 11 Similar a Bcl2 , Muerte Celular/genética , Colitis/inducido químicamente , Citocinas/biosíntesis , Sulfato de Dextran/efectos adversos , Inflamación/genética , Inflamación/inmunología , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patología , Proteínas de la Membrana/genética , Ratones , Ratones Noqueados , Fenotipo , Proteínas Proto-Oncogénicas/genética , Prolapso Rectal/genética
12.
Digestion ; 86(1): 34-47, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22710419

RESUMEN

BACKGROUND: In normal mucosa, intestinal lamina propria macrophages (IMACs) maintain tolerance against food antigens and the commensal bacterial flora. Several mechanisms have been identified that mediate tolerance. The ubiquitin-proteasome system (UPS) is a large multiprotein complex that degrades cellular proteins. As the UPS may modulate immune functions of IMACs, we performed a detailed investigation of UPS expression and function under normal conditions and in cells derived from patients suffering from inflammatory bowel disease (IBD). METHODS: IMACs were isolated from intestinal mucosa. mRNA expression of macrophages differentiated in vitro (i.v. MACs) and IMACs was compared by Affymetrix® oligonucleotide arrays. Quantitative Taqman-PCR was performed on five exemplary proteasomal and five ubiquitinylation genes each. Proteins were analyzed by immunohistochemistry and Western blotting. Proteasome function was assessed by a fluorimetric test. RESULTS: Affymetrix analysis showed downregulation of mRNA expression of almost all represented proteasomal and of 22 ubiquitination-associated genes in IMACs as compared to i.v. MACs and monocytes. By quantitative PCR, up to tenfold higher mRNA expression of 10 exemplary genes of the UPS (UBE2A, UBE2D2, UBE2L6, USP14, UBB and ATPase2, ß2, ß5, ß2i/MECL-1, ß5i/LMP7) was demonstrated in i.v. MACs as compared to IMACs. Immunohistochemistry and Western blots confirmed these findings in intestinal mucosa of controls and patients suffering from diverticulitis. In contrast, a significant increase in protein amounts was found in mucosa of patients with IBD. CONCLUSION: Reduced expression of subunits of the UPS in IMACs of normal mucosa supports the concept of the presence of a nonreactive, anergic macrophage phenotype in the gut under normal conditions. Reinduction in IMACs of IBD mucosa reflects activated IMACs which can present antigenic peptides and thus support inflammation.


Asunto(s)
Colitis Ulcerosa/genética , Enfermedad de Crohn/genética , Regulación hacia Abajo , Mucosa Intestinal/enzimología , Macrófagos/enzimología , Complejos de Ubiquitina-Proteína Ligasa/genética , Complejos de Ubiquitina-Proteína Ligasa/metabolismo , Adenosina Trifosfatasas/genética , Diferenciación Celular , Células Cultivadas , Colitis Ulcerosa/enzimología , Colon/enzimología , Enfermedad de Crohn/enzimología , Diverticulitis/enzimología , Diverticulitis/genética , Humanos , Análisis por Micromatrices , ATPasas de Translocación de Protón Mitocondriales/genética , ATPasas de Translocación de Protón Mitocondriales/metabolismo , Complejo de la Endopetidasa Proteasomal/genética , Complejo de la Endopetidasa Proteasomal/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , ATPasas Transportadoras de Calcio del Retículo Sarcoplásmico/genética , ATPasas Transportadoras de Calcio del Retículo Sarcoplásmico/metabolismo , Ubiquitina/genética , Ubiquitina/metabolismo , Ubiquitina Tiolesterasa/genética , Ubiquitina Tiolesterasa/metabolismo , Enzimas Ubiquitina-Conjugadoras/genética , Enzimas Ubiquitina-Conjugadoras/metabolismo , Complejos de Ubiquitina-Proteína Ligasa/sangre
13.
Digestion ; 85(3): 192-201, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22286692

RESUMEN

BACKGROUND: The first identified susceptibility gene for Crohn's disease, NOD2, acts as a sensor for the bacterial-wall peptidoglycan fragment muramyl dipeptide (MDP) and activates the transcription factor nuclear factor-κB (NF-κB). Upon NF-κB activation, intestinal macrophages (IMACs) induce expression of macrophage inflammatory protein (MIP)-3α to attract memory T lymphocytes. We therefore investigated the influence of NOD2 ligation of IMAC differentiation and functional MIP-3α induction. METHODS: Human embryonal kidney HEK293 cells were transfected with NOD2 wild-type (NOD2(WT)) and the NOD2 SNP13 variant (NOD2(L1007fsinsC)) and stimulated with MDP. Recruitment of CD45R0+ and Th17 cells was determined by immunohistochemistry. RESULTS: Endogenous NOD2 stimulation was followed by a dose-dependent increase in MIP-3α secretion in MONO-MAC-6 (MM6) cells. MIP-3α mRNA was also significantly (*p < 0.05) induced in HEK293 transfected with NOD2(WT) via MDP ligation. In vivo cell-cell contacts between IMACs and CD45R0+ memory T cells as well as recruitment of Th17 cells in patients of NOD2 variants were unchanged as compared to wild-type patients. CONCLUSION: Our data demonstrate a dose-dependent increase in MIP-3α secretion in the human myeloid cell line MM6 upon MDP. However, MIP-3α-driven recruitment of Th17 cells or CD45R0+ memory T lymphocytes is not affected in patients carrying heterozygous NOD2 variants.


Asunto(s)
Quimiocina CCL20/metabolismo , Enfermedad de Crohn/metabolismo , Macrófagos/metabolismo , Proteína Adaptadora de Señalización NOD2/fisiología , Acetilmuramil-Alanil-Isoglutamina/farmacología , Adolescente , Adulto , Anciano , Enfermedad de Crohn/patología , Cartilla de ADN/química , Relación Dosis-Respuesta a Droga , Ensayo de Inmunoadsorción Enzimática , Expresión Génica , Predisposición Genética a la Enfermedad , Células HEK293/efectos de los fármacos , Humanos , Inmunohistoquímica , Mucosa Intestinal/patología , Macrófagos/patología , Persona de Mediana Edad , FN-kappa B/metabolismo , ARN Mensajero/metabolismo , Reacción en Cadena en Tiempo Real de la Polimerasa , Activación Transcripcional , Transfección , Adulto Joven
14.
Hernia ; 16(3): 321-5, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22169984

RESUMEN

BACKGROUND: The shrinkage of mesh has been cited as a possible explanation for hernia recurrence. Expanded polytetrafluoroethylene (ePTFE) is unique in that it can be visualized on computed tomography (CT). Some animal studies have shown a greater than 40% rate of contraction of ePTFE; however, very few human studies have been performed. STUDY DESIGN: A total of 815 laparoscopic incisional/ventral hernia (LIVH) repairs were performed by a single surgical group. DualMesh Plus (ePTFE) (WL Gore & Associates, Newark, DE) was placed in the majority of these patients using both transfascial sutures and tack fixation. Fifty-eight patients had postoperative CTs of the abdomen and pelvis with ePTFE and known transverse diameter of the implanted mesh. The prosthesis was measured on the CT using the AquariusNet software program (TeraRecon, San Mateo, CA), which outlines the mesh and calculates the total length. Data were collected regarding the original mesh size, known linear dimension of mesh, seroma formation, and time interval since mesh implantation in months. RESULTS: The mean shrinkage rate was 6.7%. The duration of implantation ranged from 6 weeks to 78 months, with a median of 15 months. Seroma was seen in 8.6% (5) of patients. No relationship was identified between the percentage of shrinkage and the original mesh size (P = 0.78), duration of time implanted (P = 0.57), or seroma formation (P = 0.074). In 27.5% (16) of patients, no shrinkage of mesh was identified. Of the patients who did experience mesh shrinkage, the range of shrinkage was 2.6-25%. CONCLUSIONS: Our results are markedly different from animal studies and show that ePTFE has minimal shrinkage after LIVH repair. The use of transfascial sutures in addition to tack fixation may have an implication on the mesh contraction rates.


Asunto(s)
Herniorrafia/efectos adversos , Politetrafluoroetileno/efectos adversos , Mallas Quirúrgicas/efectos adversos , Hernia Ventral/cirugía , Humanos , Laparoscopía , Retención de la Prótesis , Recurrencia , Estudios Retrospectivos , Seroma/etiología , Suturas , Factores de Tiempo , Tomografía Computarizada por Rayos X
15.
J Microsc ; 242(1): 46-54, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21118230

RESUMEN

The Her2/neu tyrosine kinase receptor is a member of the epidermal growth factor family. It plays an important role in tumour genesis of certain types of breast cancer and its overexpression correlates with distinct diagnostic and therapeutic decisions. Nevertheless, it is still under intense investigation to improve diagnostic outcome and therapy control. In this content, we applied spectral precision distance/position determination microscopy, a technique based on the general principles of localization microscopy in order to study tumour typical conformational changes of receptor clusters on cell membranes. We examined two different mamma carcinoma cell lines as well as cells of a breast biopsy of a healthy donor. The Her2/neu receptor sites were labelled by immunofluorescence using conventional fluorescent dyes (Alexa conjugated antibodies). The characterization of the Her2/neu distribution on plasma membrane sections of 176 different cells yielded a total amount of 20 637 clusters with a mean diameter of 67 nm. Statistical analysis on the single molecule level revealed differences in clustering of Her2/neu between all three different cell lines. We also showed that using spectral precision distance/position determination microscopy, a dual colour reconstruction of the 3D spatial arrangement of Her2/neu and Her3 is possible. This indicates that spectral precision distance/position determination microscopy could be used as an enhanced tool offering additional information of Her2/neu receptor status.


Asunto(s)
Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Microscopía , Receptor ErbB-2/metabolismo , Línea Celular , Línea Celular Tumoral , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Receptor ErbB-2/química , Receptor ErbB-3/metabolismo
16.
Int J Inflam ; 2010: 814326, 2010 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-21188220

RESUMEN

Graft-versus-Host Disease (GvHD) is the most serious complication of allogeneic stem cell transplantation (SCT) and results from an activation of donor lymphocytes by recipient antigen-presenting cells (APCs). For a long time, it has been postulated that the intestinal microflora and endotoxin exert a crucial step in this APC activation, as there is early and severe gastrointestinal damage induced by pretransplant conditioning. With the detailed description of pathogen-associated molecular patterns and pathogen recognition receptors single nucleotide polymorphisms of TLRs and especially NOD2 have been identified as potential risk factors of GvHD and transplant related complications thus further supporting the crucial role of innate immunity in SCT, related complications. Gastrointestinal decontamination and neutralization of endotoxin have been used to interfere with this early axis of activation with some success but more specific approaches of modulation of innate immunity are needed for further improvement of clinical outcome.

17.
Climacteric ; 13(3): 219-27, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20423242

RESUMEN

OBJECTIVE: To investigate the pharmacokinetics of 10 microg and 25 microg 17beta-estradiol (E2) vaginal tablets in postmenopausal women with vaginal atrophy. METHODS: Fifty-eight women received either 10 microg or 25 microg estradiol vaginal tablets, administered once daily for 2 weeks, followed by twice-weekly dosing for 10 weeks. Blood samples were taken over 24 h at baseline (day -1) and days 1, 14, 82 and 83. Estradiol (E2), estrone (E1) and estrone sulfate (E1S) levels were quantified by gas chromatography-mass spectrometry (GCMS) and assessed by the average plasma concentration from time 0 to 24 h (C(ave)) derived from the area under the curve within 24 h (AUC((0-24))) divided by 24 h. RESULTS: Mean C(ave) values were 9.39 and 19.84 pg/ml on day 1, 6.56 and 18.29 pg/ml on day 14, and 4.64 and 9.41 pg/ml on day 83 for the 10 microg and 25 microg doses, respectively. After 12 weeks, E1 and E1S levels were slightly higher with the 25 microg dose and in the same range with the 10 microg dose, as compared to baseline. CONCLUSIONS: During 12 weeks' administration, 10 microg vaginal tablets resulted in at least 50% lower mean estradiol concentrations than with the 25 microg dose within 24 h after dosing. Administering the 25 microg dose, mean E2 levels during the first 2 weeks exceeded the published reference range for postmenopausal women using the GCMS method, while, with the 10 microg dose, mean E2 levels remained in that range from the beginning, indicating minimized estradiol absorption.


Asunto(s)
Estradiol/administración & dosificación , Estradiol/farmacocinética , Estrógenos/administración & dosificación , Estrógenos/farmacocinética , Posmenopausia , Administración Intravaginal , Anciano , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Estradiol/sangre , Estrógenos/sangre , Estrona/análogos & derivados , Estrona/sangre , Femenino , Cromatografía de Gases y Espectrometría de Masas , Humanos
18.
Climacteric ; 13(3): 228-37, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20423243

RESUMEN

OBJECTIVE: The objective of the study was to evaluate the endometrial safety of a 10 microg estradiol vaginal tablet in the treatment of vaginal atrophy in postmenopausal women. METHODS: A total of 336 healthy, non-hysterectomized, postmenopausal women (age 59.5 +/- 6.16 years, 9.4 +/- 5.9 years from last menses) were treated with a 10 microg estradiol vaginal tablet for 12 months (once daily for 2 weeks and then twice weekly for 50 weeks). Endometrial histology was analyzed at baseline and at the end of the trial. RESULTS: Of the 336 enrolled subjects, 292 (86.9%) completed the 52-week study. All 336 subjects received an endometrial biopsy at baseline, and 283 had biopsy results at week 52, when 258 out of the 283 biopsy samples were classified as 'atrophic' or 'inactive' endometrium. There were 21 with 'no tissue' despite a repeat biopsy attempt to obtain endometrial tissue, one had insufficient tissue with endometrial thickness >4 mm, one was 'weakly proliferative' and two revealed polyps. No cases of endometrial hyperplasia or endometrial cancer were reported. The mean endometrial thickness decreased from 2.04 mm (n = 334) from study start to 1.94 mm (n = 293) after 52 weeks, and the estradiol levels remained at the low postmenopausal level. CONCLUSIONS: After 12 months of treatment with the 10 microg estradiol vaginal tablet, there was no suggestion of endometrial stimulation and no cases of endometrial hyperplasia or cancer reported. This study provides reassuring data on the endometrial safety of treatment with the 10 microg estradiol vaginal tablet for 1 year in a large group of postmenopausal, non-hysterectomized women with vaginal atrophy.


Asunto(s)
Endometrio/diagnóstico por imagen , Endometrio/patología , Estradiol/administración & dosificación , Estrógenos/administración & dosificación , Vagina/patología , Administración Intravaginal , Atrofia , Biopsia , Estradiol/efectos adversos , Estradiol/sangre , Estrógenos/efectos adversos , Femenino , Humanos , Persona de Mediana Edad , Posmenopausia , Ultrasonografía
19.
Digestion ; 81(4): 252-64, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20130407

RESUMEN

BACKGROUND: Environmental factors are thought to play an important role in the development of Crohn's disease (CD). Immune responses against auto-antigens or food antigens may be a reason for the perpetuation of inflammation. METHODS: In a pilot study, 79 CD patients and 20 healthy controls were examined for food immunoglobulin G (IgG). Thereafter, the clinical relevance of these food IgG antibodies was assessed in a double-blind cross-over study with 40 patients. Based on the IgG antibodies, a nutritional intervention was planned. The interferon (IFN)gamma secretion of T cells was measured. Eosinophil-derived neurotoxin was quantified in stool. RESULTS: The pilot study resulted in a significant difference of IgG antibodies in serum between CD patients and healthy controls. In 84 and 83% of the patients, respectively, IgG antibodies against processed cheese and yeast were detected. The daily stool frequency significantly decreased by 11% during a specific diet compared with a sham diet. Abdominal pain reduced and general well-being improved. IFNgamma secretion of T cells increased. No difference for eosinophil-derived neurotoxin in stool was detected. CONCLUSION: A nutritional intervention based on circulating IgG antibodies against food antigens showed effects with respect to stool frequency. The mechanisms by which IgG antibodies might contribute to disease activity remain to be elucidated.


Asunto(s)
Anticuerpos Antiidiotipos/inmunología , Enfermedad de Crohn/dietoterapia , Enfermedad de Crohn/inmunología , Hipersensibilidad a los Alimentos/inmunología , Inmunoglobulina G/inmunología , Dolor Abdominal/fisiopatología , Adolescente , Adulto , Análisis de Varianza , Enfermedad de Crohn/sangre , Estudios Cruzados , Defecación/fisiología , Progresión de la Enfermedad , Método Doble Ciego , Ensayo de Inmunoadsorción Enzimática , Neurotoxina Derivada del Eosinófilo/análisis , Neurotoxina Derivada del Eosinófilo/inmunología , Heces , Femenino , Alimentos , Estado de Salud , Humanos , Masculino , Persona de Mediana Edad , Proyectos Piloto , Probabilidad , Pronóstico , Recurrencia , Valores de Referencia , Medición de Riesgo , Resultado del Tratamiento , Adulto Joven
20.
J Microsc ; 235(2): 163-71, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19659910

RESUMEN

We present a novel technique of far-field localization nanoscopy combining spectral precision distance microscopy with widely used fluorochromes like the Green Fluorescent Protein (GFP) derivatives eGFP, EmGFP, Yellow Fluorescent Protein (YFP) and eYFP, synthetic dyes like Alexa 488 and Alexa 568, as well as fluoresceine derivates. Spectral precision distance microscopy allows the surpassing of conventional resolution limits in fluorescence far-field microscopy by precise object localization after the optical isolation of single signals in time. Based on the principles of this technique, our novel nanoscopic method was realized for laser optical precision localization and image reconstruction with highly enhanced optical resolution in intact cells. This allows for spatial assignment of individual fluorescent molecules with nanometre precision. The technique is based on excitation intensity dependent reversible photobleaching of the molecules used combined with fast time sequential imaging under appropriate focusing conditions. A meaningful advantage of the technique is the simple applicability as a universal tool for imaging and investigations to the major part of already available preparations according to standard protocols. Using the above mentioned fluorophores, the positions of single molecules within cellular structures were determined by visible light with an estimated localization precision down to 3 nm; hence distances in the range of 10-30 nm were resolved between individual fluorescent molecules allowing to apply different quantitative structure analysis tools.


Asunto(s)
Núcleo Celular/ultraestructura , Células Epiteliales/ultraestructura , Microscopía Fluorescente/métodos , Línea Celular Tumoral , Colorantes Fluorescentes/metabolismo , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Coloración y Etiquetado/métodos
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