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1.
Am J Case Rep ; 24: e941337, 2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-37910441

RESUMEN

BACKGROUND Foot ulcers are high-morbidity and debilitating complications of diabetes mellitus, and carry significantly increased rates of associated major amputations. They contribute to significantly worse quality of life. Osteomyelitis is a frequent complication of diabetic foot ulcers, since bacteria can contiguously spread from soft tissues to the bone, involving the cortex first and then the bone marrow. Unfortunately, clinically unsuspected osteomyelitis is frequent in persisting diabetic foot ulcers. It is associated with limb amputations and increased mortality. CASE REPORT We describe a 76-year-old man with long-standing insulin-treated type 2 diabetes, who experienced extensively drug-resistant Enterococcus faecalis diabetic foot myositis and osteomyelitis associated with sepsis. He was successfully treated with surgical debridement combined with the administration of teicoplanin plus rifampicin in the outpatient setting, completing, in total, a twelve-week course of antibiotic therapy. CONCLUSIONS Clinically unsuspected osteomyelitis in patients with persisting diabetic foot ulcers has been associated with infections from highly resistant bacteria. Early and accurate diagnosis of diabetic foot osteomyelitis, as well as proper therapeutic approach (antimicrobial and surgical), is of great importance to reduce the risk of minor and major amputations, septic shock leading to multiple organ failure, and overall mortality.


Asunto(s)
Diabetes Mellitus Tipo 2 , Pie Diabético , Miositis , Osteomielitis , Masculino , Humanos , Anciano , Pie Diabético/complicaciones , Rifampin/uso terapéutico , Teicoplanina/uso terapéutico , Enterococcus faecalis , Preparaciones Farmacéuticas , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Pacientes Ambulatorios , Calidad de Vida , Osteomielitis/microbiología , Antibacterianos/uso terapéutico , Miositis/tratamiento farmacológico
2.
Calcif Tissue Int ; 112(1): 66-73, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36261653

RESUMEN

Increasing interest has focussed on the possible role of alterations in the microbiome in the pathogenesis of metabolic disease, inflammatory disease, and osteoporosis. Here we examined the role of the microbiome in a preclinical model of osteoarthritis in mice subjected to destabilisation of medical meniscus (DMM). The intestinal microbiome was depleted by broad-spectrum antibiotics from 1 week before birth until the age of 6 weeks when mice were subjected reconstitution of the microbiome with faecal microbial transplant (FMT) followed by the administration of a mixture of probiotic strains Lacticaseibacillus paracasei 8700:2, Lactiplantibacillus plantarum HEAL9 and L. plantarum HEAL19 or vehicle. All mice were subjected to DMM at the age of 8 weeks. The severity of osteoarthritis was evaluated by histological analysis and effects on subchondral bone were investigated by microCT analyses. The combination of FMT and probiotics significantly inhibited cartilage damage at the medial femoral condyle such that the OARSI score was 4.64 ± 0.32 (mean ± sem) in the FMT and probiotic group compared with 6.48 ± 0.53 in the FMT and vehicle group (p = 0.007). MicroCT analysis of epiphyseal bone from the femoral condyle showed that the probiotic group had higher BV/TV, increased Tb.Th, and moderately thicker subchondral bone plates than the control group. There was no difference between groups in joint inflammation or in serum concentrations of inflammatory cytokines and chemokines. We conclude that treatment with probiotics following FMT in mice where the microbiome has been depleted inhibits DMM-induced cartilage damage and impacts on the structure of subchondral bone particularly at the femoral condyle. While further studies are required to elucidate the mechanism of action, our research suggests that these probiotics may represent a novel intervention for the treatment of osteoarthritis.


Asunto(s)
Cartílago Articular , Osteoartritis , Ratones , Animales , Cartílago Articular/metabolismo , Osteoartritis/metabolismo , Huesos/metabolismo , Articulación de la Rodilla/patología , Modelos Animales de Enfermedad
3.
Bioresour Technol ; 354: 127172, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35447331

RESUMEN

The organic fraction of municipal solid waste (OFMSW) was used for biorefinery development within a circular bioeconomy context towards extraction of lipids/fats and proteins with 100% and 68% recovery yields, respectively, as well as succinic acid (SA) production. A nutrient-rich hydrolysate (89.1 g/L sugars) produced using crude enzymes derived via solid state fermentation of Aspergillus awamori, was employed in Actinobacillus succinogenes fermentation leading to 31.7 gSA/L with 0.68 g/g yield and 0.67 g/L/h productivity. The SA minimum selling price ($1.13-2.39/kgSA) considering 60,000 tSA/year production varied depending on co-product market prices and OFMSW management fees. The biorefinery using 1000 kg OFMSW contributes 35% lower CO2 emissions than conventional processes for the production of 105 kg vegetable oil, 87 kg vegetable protein and 206.4 kg fossil-SA considering also the CO2 emissions due to OFMSW landfilling. The proposed OFMSW biorefinery leads to cost-competitive SA production with lower CO2 emissions for OFMSW treatment.


Asunto(s)
Residuos Sólidos , Ácido Succínico , Reactores Biológicos , Dióxido de Carbono/análisis , Ambiente , Residuos Sólidos/análisis
4.
Pharmacol Res ; 175: 105928, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34800625

RESUMEN

To address the inconsistent findings from studies that used different models to explore the role of classical cannabinoid type 1 (CB1) and 2 (CB2) receptors in skeletal remodelling, we searched Medline, Web of Science and Embase for relevant studies from inception to June 23, 2020. We identified 38 in vitro, 34 in vivo and 9 human studies. A meta-analysis of in vitro studies showed that exposure to the inverse-agonists AM251 (mean difference [MD]:-26.75, 95% confidence interval [CI]:-45.36,-8.14, p = 0.005), AM630 (standardised[std.] MD:-3.11, CI:-5.26,-0.97, p = 0.004; SR144528, std.MD:-4.88, CI -7.58,-2.18, p = 0.0004) and CBD (std.MD:-1.39, CI -2.64,-0.14, p = 0.03) is associated with reduced osteoclastogenesis, whereas the endocannabinoid 2-AG (std.MD:2.00, CI:0.11-3.89, p = 0.04) and CB2-selective agonist HU308 (MD:19.38, CI:11.75-27.01, p < 0.00001) were stimulatory. HU308 also enhanced osteoblast differentiation (std.MD:2.22, CI:0.95-3.50, p = 0.0006) and activity (std.MD:2.97, CI:1.22-4.71, p = 0.0008). In models of bone loss, CB1/2 deficiency enhanced peak bone volume (std.MD:3.70, CI:1.77-5.63, p = 0.0002) but reduced bone formation (std.MD:-0.54, CI:-0.90,-0.17, p = 0.004) in female mice. In male rats, CB1/2 deficiency (std.MD:2.31, CI:0.30-4.33, p = 0.02) and AM251 or CBD treatments (std.MD:2.19, CI:0.46-3.93, p = 0.01) enhanced bone volume. CB1/2 deficiency (std.MD:9.78, CI:4.96-14.61, p < 0.0001) and AM251 or AM630 treatments (std.MD:28.19, CI:19.13-37.25, p < 0.0001) were associated with osteoprotection. The CB2-selective agonists JWH133 and 4Q3C enhanced bone volume in arthritic rodents (std.MD:14.45, CI:2.08-26.81, p = 0.02). In human, CB2 SNPs (AA:rs2501431, MD:-0.28, CI:-0.55,-0.01, p = 0.04; CC:rs2501432, MD:-0.29, CI:-0.56,-0.02, p = 0.03) were associated with reduced bone mineral density, however the association of Marijuana use remains unclear. Thus, CB1/2 modulation is associated with altered bone metabolism, however findings are confounded by low study number and heterogenicity of models.


Asunto(s)
Remodelación Ósea/efectos de los fármacos , Moduladores de Receptores de Cannabinoides/administración & dosificación , Animales , Desarrollo Óseo/efectos de los fármacos , Huesos/efectos de los fármacos , Moduladores de Receptores de Cannabinoides/efectos adversos , Humanos
5.
Biotechnol Biofuels ; 13: 72, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32322302

RESUMEN

BACKGROUND: Despite its high market potential, bio-based succinic acid production experienced recently a declining trend because the initial investments did not meet the expectations for rapid market growth. Thus, reducing the succinic acid production cost is imperative to ensure industrial implementation. RESULTS: Succinic acid production has been evaluated using hydrolysates from the organic fraction of municipal solid waste (OFMSW) collected from MSW treatment plants. A tailor-made enzymatic cocktail was used for OFMSW hydrolysate production containing up to 107.3 g/L carbon sources and up to 638.7 mg/L free amino nitrogen. The bacterial strains Actinobacillus succinogenes and Basfia succiniciproducens were evaluated for succinic acid production with the latter strain being less efficient due to high lactic acid production. Batch A. succinogenes cultures supplemented with 5 g/L yeast extract and 5 g/L MgCO3 reached 29.4 g/L succinic acid with productivity of 0.89 g/L/h and yield of 0.56 g/g. Continuous cultures at dilution rate of 0.06 h-1 reached 21.2 g/L succinic acid with yield of 0.47 g/g and productivity of 1.27 g/L/h. Downstream separation and purification of succinic acid was achieved by centrifugation, treatment with activated carbon, acidification with cation exchange resins, evaporation and drying, reaching more than 99% purity. Preliminary techno-economic evaluation has been employed to evaluate the profitability potential of bio-based succinic acid production. CONCLUSIONS: The use of OFMSW hydrolysate in continuous cultures could lead to a minimum selling price of 2.5 $/kg at annual production capacity of 40,000 t succinic acid and OFMSW hydrolysate production cost of 25 $/t sugars.

6.
Bioresour Technol ; 274: 343-352, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30529482

RESUMEN

This study focuses on the optimisation of 2,3-butanediol (BDO) production in fed-batch cultures carried out with the bacterial strain Enterobacter ludwigii using very high polarity (VHP) sugar from sugarcane mills. Various kLa values were evaluated using either complex or synthetic fermentation media demonstrating that the latter enhance BDO production efficiency with low by-product formation. The pH (6.3) and temperature (33.9 °C) employed in fed-batch bioreactor cultures has been optimised via experimental design. Fed-batch cultures carried out at the optimum temperature and pH and varying kLa values resulted in BDO concentration, yield and productivity of 86.8 g/L, 0.37 g/g and 3.95 g L-1 h-1. Using this fermentation efficiency, the minimum selling price of BDO for annual production capacities of 10,000 t and 50,000 t was estimated at $3.12/kg and $2.67/kg, respectively, for a VHP cane sugar market price of $0.4/kg.


Asunto(s)
Reactores Biológicos , Butileno Glicoles/metabolismo , Saccharum/metabolismo , Técnicas de Cultivo Celular por Lotes , Reactores Biológicos/economía , Reactores Biológicos/microbiología , Fermentación , Temperatura
7.
J Inflamm Res ; 12: 1-14, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30588059

RESUMEN

Chronic, noncommunicable, and inflammation-associated diseases remain the largest cause of morbidity and mortality globally and within the United States. This is mainly due to our limited understanding of the molecular mechanisms that underlie these complex pathologies. The available evidence indicates that studies of epigenetics (traditionally defined as the heritable changes to gene expression that are independent of changes to DNA) are significantly advancing our knowledge of these inflammatory conditions. This review will focus on epigenetic studies of three diseases, that are among the most burdensome globally: cardiovascular disease, the number one cause of deaths worldwide, type 2 diabetes and, Alzheimer's disease. The current status of epigenetic research, including the ability to predict disease risk, and key pathophysiological defects are discussed. The significance of defining the contribution of epigenetic defects to nonresolving inflammation and aging, each associated with these diseases, is highlighted, as these are likely to provide new insights into inflammatory disease pathogenesis.

8.
Mol Diagn Ther ; 22(1): 11-23, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-28900867

RESUMEN

Omics technology presents an exciting and timely opportunity to improve our understanding of the molecular etiology and pathogenesis of the group of chronic, heterogeneous, inflammatory disorders that comprise inflammatory bowel disease (IBD). Interest in the use of omics in the biomedical and clinical research communities is gaining pace due to its potential to make huge strides in our understanding of IBD causality, and pathology. Omics-related research also has applicability for biomarker discovery and the development of individualized treatments for patients, termed 'precision medicine'. This review will evaluate the omics analyses that have been performed in the context of IBD, with a focus on the significance of multi-omics IBD studies and the bioinformatic integration of omics data. Such an approach has the potential to provide a comprehensive analysis of the major determinants of IBD. The translation of omics data into individualized therapy will also be addressed. Major progress in understanding the changes that underlie inflammatory bowel diseases (IBDs) has been achieved; however, the key molecular changes in IBD that could be targeted for better treatments are undefined. This article reviews the latest IBD research on new high-throughput technologies called 'omics', which are measurements and analyses of large numbers of molecules from patients and healthy subjects. Omics data have the potential to dramatically improve therapy by providing new information to tailor highly specific treatments to individual patients with IBD.


Asunto(s)
Biología Computacional/métodos , Enfermedades Inflamatorias del Intestino/etiología , Epigenómica , Predisposición Genética a la Enfermedad , Humanos , Enfermedades Inflamatorias del Intestino/genética , Enfermedades Inflamatorias del Intestino/metabolismo , Enfermedades Inflamatorias del Intestino/microbiología , Metabolómica , Microbiota , Medicina de Precisión , Proteómica
9.
J Orthop Res ; 35(5): 947-955, 2017 05.
Artículo en Inglés | MEDLINE | ID: mdl-27517731

RESUMEN

We have used a murine Achilles tendinopathy model to investigate whether tissue changes (such as collagen disorganization, chondroid metaplasia, and loss of tensile properties) which are broadly characteristic of human tendinopathies, are accompanied by changes in the expression of chromatin-modifying enzymes and the methylation status of promoter regions of tendon cell DNA. Tendinopathy was induced by two intra-tendinous TGF-ß1 injections followed by cage activity or treadmill running for up to 28 days. Activation of DNA methyltransferases occurred at 3 days after the TGF-ß1 injections and also at 14 days, but only with treadmill activity. Genome-wide Methyl Mini-Seq™ analysis identified 19 genes with differentially methylated promoters, five of which perform functions with an apparent direct relevance to tendinopathy (Leprel2, Foxf1, Mmp25, Igfbp6, and Peg12). The functions of the genes identified included collagen fiber assembly and pericellular interactions, therefore their perturbation could play a role in the characteristic disorganization of fibers in affected tendons. We postulate that a study of the functional genomics of these genes in animal and human tendon could further delineate the pathogenesis of this multi-factorial complex disease. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:947-955, 2017.


Asunto(s)
Metilación de ADN , Tendinopatía/metabolismo , Tendón Calcáneo/patología , Animales , Proteínas Portadoras/genética , Modelos Animales de Enfermedad , Factores de Transcripción Forkhead/genética , Proteínas Ligadas a GPI/genética , Expresión Génica , Estudio de Asociación del Genoma Completo , Masculino , Metaloproteinasas de la Matriz Asociadas a la Membrana/genética , Ratones Endogámicos C57BL , Proteínas de Neoplasias/genética , Procolágeno-Prolina Dioxigenasa/genética , Regiones Promotoras Genéticas , Tendinopatía/patología
10.
Clin Epigenetics ; 8: 30, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26973718

RESUMEN

BACKGROUND: Fibrosis of the intestine is a common and poorly understood complication of Crohn's disease (CD) characterized by excessive deposition of extracellular matrix and accompanied by narrowing and obstruction of the gut lumen. Defining the molecular characteristics of this fibrotic disorder is a vital step in the development of specific prediction, prevention, and treatment strategies. Previous epigenetic studies indicate that alterations in DNA methylation could explain the mechanism by which mesenchymal cells adopt the requisite pro-fibrotic phenotype that promotes fibrosis progression. However, to date, genome-wide analysis of the DNA methylome of any type of human fibrosis is lacking. We employed an unbiased approach using deep sequencing to define the DNA methylome and transcriptome of purified fibrotic human intestinal fibroblasts (HIF) from the colons of patients with fibrostenotic CD. RESULTS: When compared with normal fibroblasts, we found that the majority of differential DNA methylation was within introns and intergenic regions and not associated with CpG islands. Only a low percentage occurred in the promoters and exons of genes. Integration of the DNA methylome and transcriptome identified regions in three genes that inversely correlated with gene expression: wingless-type mouse mammary tumor virus integration site family, member 2B (WNT2B) and two eicosanoid synthesis pathway enzymes (prostacyclin synthase and prostaglandin D2 synthase). These findings were independently validated by RT-PCR and bisulfite sequencing. Network analysis of the data also identified candidate molecular interactions relevant to fibrosis pathology. CONCLUSIONS: Our definition of a genome-wide fibrosis-specific DNA methylome provides new gene networks and epigenetic states by which to understand mechanisms of pathological gene expression that lead to fibrosis. Our data also provide a basis for development of new fibrosis-specific therapies, as genes dysregulated in fibrotic Crohn's disease, following functional validation, can serve as new therapeutic targets.


Asunto(s)
Enfermedad de Crohn/genética , Metilación de ADN/genética , Islas de CpG/genética , Enfermedad de Crohn/patología , Sistema Enzimático del Citocromo P-450/genética , Fibroblastos/patología , Fibrosis , Expresión Génica/genética , Estudio de Asociación del Genoma Completo , Glicoproteínas/genética , Humanos , Regiones Promotoras Genéticas , Transcriptoma/genética , Proteínas Wnt/genética
11.
Am J Pathol ; 185(6): 1624-37, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25864926

RESUMEN

Intestinal epithelial cell (IEC) death is typical of inflammatory bowel disease (IBD). We investigated: i) whether IEC-released necrotic cell products (proinflammatory mediators) amplify mucosal inflammation, ii) the capacity of necrotic cell lysates from HT29 cells or human IECs to induce human intestinal fibroblasts' (HIF) production of IL-6 and IL-8, and iii) whether IL-1α, released by injured colonocytes, exacerbated experimental IBD. Necrotic cell lysates potently induced HIF IL-6 and IL-8 production independent of Toll-like receptors 2 and 4, receptor for advanced glycation end-products, high-mobility group box 1, uric acid, IL-33, or inflammasome activation. IL-1α was the key IEC-derived necrotic cell product involved in HIF cytokine production. IL-1α-positive cells were identified in the epithelium in human IBD and dextran sulfate sodium (DSS)-induced colitis. IL-1α was detected in the stool of colitic mice before IL-1ß. IL-1α enemas reactivated inflammation after DSS colitis recovery, induced IL-1 receptor expression in subepithelial fibroblasts, and activated de novo inflammation even in mice without overt colitis, after the administration of low-dose DSS. IL-1α amplifies gut inflammation by inducing cytokine production by mesenchymal cells. IL-1α-mediated IEC-fibroblast interaction may be involved in amplifying and perpetuating inflammation, even without obvious intestinal damage. IL-1α may be a target for treating early IBD or preventing the reactivation of IBD.


Asunto(s)
Colitis/metabolismo , Fibroblastos/metabolismo , Inflamación/metabolismo , Interleucina-1alfa/metabolismo , Mucosa Intestinal/metabolismo , Animales , Colitis/inducido químicamente , Colitis/patología , Sulfato de Dextran , Modelos Animales de Enfermedad , Fibroblastos/patología , Células HT29 , Humanos , Inflamación/patología , Interleucina-6/metabolismo , Interleucina-8/metabolismo , Intestinos/patología , Ratones
12.
Gastroenterology ; 148(7): 1405-1416.e3, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25701737

RESUMEN

BACKGROUND & AIMS: Defects in colonic epithelial barrier defenses are associated with ulcerative colitis (UC). The proteins that regulate bacterial clearance in the colonic epithelium have not been completely identified. The Drosophila chromosome-associated protein D3 (dCAP-D3) regulates responses to bacterial infection. We examined whether CAP-D3 promotes bacterial clearance in human colonic epithelium. METHODS: Clearance of Salmonella or adherent-invasive Escherichia coli LF82 was assessed by gentamycin protection assays in HT-29 and Caco-2 cells expressing small hairpin RNAs against CAP-D3. We used immunoblot assays to measure levels of CAP-D3 in colonic epithelial cells from patients with UC and healthy individuals (controls). RNA sequencing identified genes activated by CAP-D3. We analyzed the roles of CAP-D3 target genes in bacterial clearance using gentamycin protection and immunofluorescence assays and studies with pharmacologic inhibitors. RESULTS: CAP-D3 expression was reduced in colonic epithelial cells from patients with active UC. Reduced CAP-D3 expression decreased autophagy and impaired intracellular bacterial clearance by HT-29 and Caco-2 colonic epithelial cells. Lower levels of CAP-D3 increased transcription of genes encoding SLC7A5 and SLC3A2, the products of which heterodimerize to form an amino acid transporter in HT-29 cells after bacterial infection; levels of SLC7A5-SLC3A2 were increased in tissues from patients with UC compared with controls. Reduced CAP-D3 in HT-29 cells resulted in earlier recruitment of SLC7A5 to Salmonella-containing vacuoles, increased activity of mTORC1, and increased survival of bacteria. Inhibition of SLC7A5-SLC3A2 or mTORC1 activity rescued the bacterial clearance defects of CAP-D3-deficient cells. CONCLUSIONS: CAP-D3 down-regulates transcription of genes that encode amino acid transporters (SLC7A5 and SLC3A2) to promote bacterial autophagy by colon epithelial cells. Levels of CAP-D3 protein are reduced in patients with active UC; strategies to increase its levels might restore mucosal homeostasis to patients with active UC.


Asunto(s)
Proteínas de Ciclo Celular/metabolismo , Células Epiteliales/metabolismo , Células Epiteliales/microbiología , Escherichia coli/fisiología , Cadena Pesada de la Proteína-1 Reguladora de Fusión/metabolismo , Mucosa Intestinal/metabolismo , Mucosa Intestinal/microbiología , Transportador de Aminoácidos Neutros Grandes 1/metabolismo , Salmonella/fisiología , Adenosina Trifosfatasas , Autofagia , Células CACO-2 , Proteínas de Ciclo Celular/genética , Colitis Ulcerosa/inmunología , Colitis Ulcerosa/metabolismo , Colitis Ulcerosa/microbiología , Enfermedad de Crohn/inmunología , Enfermedad de Crohn/metabolismo , Enfermedad de Crohn/microbiología , Proteínas de Drosophila , Células Epiteliales/inmunología , Escherichia coli/inmunología , Cadena Pesada de la Proteína-1 Reguladora de Fusión/genética , Regulación de la Expresión Génica , Células HT29 , Humanos , Inmunidad Innata , Mucosa Intestinal/inmunología , Transportador de Aminoácidos Neutros Grandes 1/genética , Diana Mecanicista del Complejo 1 de la Rapamicina , Viabilidad Microbiana , Complejos Multiproteicos/metabolismo , Interferencia de ARN , Salmonella/inmunología , Transducción de Señal , Serina-Treonina Quinasas TOR/metabolismo , Factores de Tiempo , Transcripción Genética , Transfección
13.
Curr Opin Gastroenterol ; 29(4): 370-7, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23743674

RESUMEN

PURPOSE OF REVIEW: Epigenetic studies are transforming our understanding of a variety of complex pathological conditions including cancer, autoimmune, and inflammatory diseases. A selection of the major recent advances in this area will be reviewed, focusing on the important emerging themes that are relevant to these diseases including inflammatory bowel disease (IBD). RECENT FINDINGS: The main current themes that will be addressed on the role of epigenetics in disease pathogenesis include current understanding of the nature and function of histone modifications and DNA methylation; the connection between epigenetics and metabolic pathways; new studies on the mechanism of heritability of epigenetic changes; the role of stochastic noise and the expanding research on chromatin readers and their potential as selective therapeutic targets. The recent contribution of epigenetic modifications in defining the molecular basis of IBD and how such changes may act as fine-tuners of gene expression in these intestinal disorders are also discussed. SUMMARY: Published evidence over the last 12-18 months indicates that targeting epigenetic factors can be efficacious in cancer and inflammatory disease. All the indications are that future research will continue to reveal new epigenetic targets and mechanisms that will advance the prospects for selective epigenetic therapy for IBD and other complex diseases.


Asunto(s)
Epigenómica/métodos , Enfermedades Inflamatorias del Intestino/genética , Investigación Biomédica/métodos , Metilación de ADN , Epigénesis Genética , Predisposición Genética a la Enfermedad , Histonas/metabolismo , Humanos
14.
Inflamm Bowel Dis ; 19(7): 1354-64, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23635716

RESUMEN

BACKGROUND: Fibrosis of the intestine is currently an irreversible complication of inflammatory bowel disease; yet, little is understood of the underlying pathogenesis and antifibrotic strategies remain elusive. To develop effective therapies, knowledge of the mechanism of transcription and excessive deposition of type I collagen, a hallmark of fibrosis, is needed. We have shown previously that endothelial-to-mesenchymal transition (EndoMT) contributes to the pool of intestinal fibrotic cells and that a cytokine cocktail (interleukin 1-ß, tumor necrosis factor α, and transforming growth factor ß) induces collagen I alpha 2 (COL1A2) mRNA and protein. METHODS: Chromatin immunoprecipitation assays on pure cultures of human intestinal mucosal endothelial cells undergoing EndoMT were performed with antibodies to specific histone modifications and RNA polymerase II. Reverse transcriptase-PCR was used to quantify the levels of Col1A2 and endothelial-specific von Willebrand factor (vWF) mRNA. RESULTS: We showed that cytokines induce selective chromatin modifications (histone 4 hyperacetylation, and hypermethylation of histone 3) and phosphorylated RNA polymerase II at the COL1A2 promoter. Hypoacetylated and hypomethylated histone 3 was detected on the repressed vWF gene. Prolonged exposure to cytokines (16 days) retained hyperacetylation of select lysines in H4 on the COL1A2 promoter. Removal of cytokines after 16 days and continued culture for 10 days showed persistent hyperacetylation at lysine 16 in histone H4. CONCLUSIONS: This is the first study to show that COL1A2 gene expression is associated with cytokine-induced, temporally ordered, and persistent chromatin modifications and suggests that these are important determinants of gene expression in EndoMT and intestinal fibrosis.


Asunto(s)
Cromatina/genética , Colágeno Tipo I/genética , Endotelio Vascular/efectos de los fármacos , Fibrosis/tratamiento farmacológico , Interleucina-1beta/farmacología , Mucosa Intestinal/patología , Mesodermo/efectos de los fármacos , Factor de Crecimiento Transformador beta1/farmacología , Factor de Necrosis Tumoral alfa/farmacología , Western Blotting , Células Cultivadas , Inmunoprecipitación de Cromatina , Colágeno Tipo I/metabolismo , Metilación de ADN , Endotelio Vascular/metabolismo , Endotelio Vascular/patología , Fibrosis/metabolismo , Fibrosis/patología , Histonas/genética , Humanos , Mucosa Intestinal/efectos de los fármacos , Mucosa Intestinal/metabolismo , Lisina/genética , Mesodermo/metabolismo , Mesodermo/patología , Regiones Promotoras Genéticas , ARN Polimerasa II/metabolismo , ARN Mensajero/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Transcripción Genética
16.
Ann Surg Oncol ; 19(11): 3375-85, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22622472

RESUMEN

BACKGROUND: The clinical assessment of the response of sarcomas to preoperative treatment is usually defined using size-based evaluation standards. For nonresectable sarcomas, hyperthermic isolated limb perfusion with TNF-α and melphalan (TM-ILP) yields high response rates. Based on our experience, we assume that anatomic radiological response criteria are insufficient to assess the degree of regression after TM-ILP. METHODS: The clinical response of 35 sarcomas to TM-ILP was assessed by unidimensional, bidimensional, and tridimensional size-based anatomical criteria, and responders were identified according to the established thresholds. The same tumors were investigated for pathological response according to the Salzer-Kuntschik regression scale (>90% devitalization) and reviewed for cystic degeneration, hemorrhage, and predominant necrotic or fibrosclerotic regression phenotype. RESULTS: None of the clinical response criteria were able to reliably identify the pathologic responders. The extent of size changes showed no association with the pathological degree of regression. The number of clinical responders was low compared with the number of pathological responders (RECIST N = 1, WHO N = 3, volumetry N = 3, pathology N = 19). The occurrence of hemorrhage and/or cystic degeneration was more frequently observed in predominant necrotic sarcomas and was associated with an increase in tumor size after TM-ILP. Furthermore, we identified the fibrosclerotic phenotype of regression to be more significantly strongly associated with posttherapeutic shrinkage than necrosis. CONCLUSIONS: Size-based clinical response evaluation is insufficient to assess clinical response in TM-ILP-treated sarcomas. The size changes of tumors after therapy reflect the type of regression rather than the extent of destruction.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Quimioterapia del Cáncer por Perfusión Regional , Hipertermia Inducida , Sarcoma/patología , Sarcoma/terapia , Carga Tumoral/efectos de los fármacos , Adulto , Anciano , Anciano de 80 o más Años , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Distribución de Chi-Cuadrado , Femenino , Humanos , Extremidad Inferior , Imagen por Resonancia Magnética , Masculino , Melfalán/administración & dosificación , Persona de Mediana Edad , Imagen Multimodal , Tomografía de Emisión de Positrones , Curva ROC , Inducción de Remisión , Sarcoma/diagnóstico por imagen , Estadísticas no Paramétricas , Tomografía Computarizada por Rayos X , Resultado del Tratamiento , Factor de Necrosis Tumoral alfa/administración & dosificación , Extremidad Superior , Adulto Joven
17.
Inflamm Bowel Dis ; 18(10): 1982-96, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22407855

RESUMEN

The purpose of this review is to introduce the exciting field of epigenetics and to describe how it could explain the mechanisms by which environmental changes induce pathological gene expression and determine cell phenotype and function in IBD. We outline how epigenetics research in the context of a variety of clinical conditions, but mainly in cancer, has begun to define the role of multiple combinations of modifications to chromatin, diverse families of enzymes, and non-coding RNAs in determining transcriptional outcomes. These findings are applicable to understanding the context-specific events that underlie the expression of genes in diseases like IBD and have the potential to reveal new targets for improved IBD therapy. The current status of epigenetics-based therapies is also summarized.


Asunto(s)
Epigénesis Genética , Enfermedades Inflamatorias del Intestino/genética , Enfermedades Inflamatorias del Intestino/patología , Humanos
18.
Am J Pathol ; 179(5): 2660-73, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21945322

RESUMEN

In addition to mesenchymal cells, endothelial cells may contribute to fibrosis through the process of endothelial-to-mesenchymal transition (EndoMT). We investigated whether human intestinal microvascular endothelial cells (HIMEC) undergo EndoMT and contribute to fibrosis in human and experimental inflammatory bowel disease (IBD). HIMEC were exposed to TGF-ß1, IL-1ß, and TNF-α or supernatants of lamina propria mononuclear cells (LPMC) and evaluated for morphological, phenotypic, and functional changes compatible with EndoMT. Genomic analysis was used to identify transcription factors involved in the transformation process. Evidence of in situ and in vivo EndoMT was sought in inflamed human and murine intestine. The combination of TGF-ß1, IL-1ß and TNF-α, or activated LPMC supernatants induced morphological and phenotypic changes consistent with EndoMT with a dominant effect by IL-1. These changes persisted after removal of the inducing agents and were accompanied by functional loss of acetylated LDL-uptake and migratory capacity, and acquisition of de novo collagen synthesis capacity. Sp1 appeared to be the main transcriptional regulator of EndoMT. EndoMT was detected in microvessels of inflammatory bowel disease (IBD) mucosa and experimental colonic fibrosis of Tie2-green fluorescent protein (GFP) reporter-expressing mice. In conclusion, chronic inflammation induces transdifferentiation of intestinal mucosal microvascular cells into mesenchymal cells, suggesting that the intestinal microvasculature contributes to IBD-associated fibrosis through the novel process of EndoMT.


Asunto(s)
Transdiferenciación Celular/fisiología , Citocinas/metabolismo , Células Endoteliales/patología , Endotelio Vascular/patología , Enfermedades Inflamatorias del Intestino/patología , Mesodermo/patología , Animales , Movimiento Celular/fisiología , Transdiferenciación Celular/genética , Células Cultivadas , Colitis/patología , Colágeno Tipo I/metabolismo , Regulación hacia Abajo , Matriz Extracelular/metabolismo , Femenino , Fibrosis , Humanos , Lipoproteínas LDL/metabolismo , Masculino , Ratones , Ratones Endogámicos , Microvasos/patología , Fenotipo , Factores de Transcripción/metabolismo , Regulación hacia Arriba
20.
Org Lett ; 11(14): 2976-9, 2009 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-19552444

RESUMEN

Two new and complementary synthetic strategies for 5'-N-chloroethylamino-5'-deoxyadenosines are presented. Additionally, the reaction kinetics of their conversion into aziridines under typical enzyme assay conditions is reported using time-resolved NMR spectroscopy. A stable photocaged derivative of 5'-N-chloroethylamino-5'-deoxyadenosine has also been synthesized, and its stability and activation in aqueous solution at physiological pH have been examined.


Asunto(s)
Aziridinas/química , Desoxiadenosinas/síntesis química , S-Adenosilmetionina/análogos & derivados , S-Adenosilmetionina/síntesis química , Aziridinas/síntesis química , Desoxiadenosinas/química , Concentración de Iones de Hidrógeno , Espectroscopía de Resonancia Magnética , Estructura Molecular , Oxidación-Reducción , Fotoquímica , S-Adenosilmetionina/química , Relación Estructura-Actividad
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