RESUMEN
cis-regulatory changes play a central role in morphological divergence, yet the regulatory principles underlying emergence of human traits remain poorly understood. Here, we use epigenomic profiling from human and chimpanzee cranial neural crest cells to systematically and quantitatively annotate divergence of craniofacial cis-regulatory landscapes. Epigenomic divergence is often attributable to genetic variation within TF motifs at orthologous enhancers, with a novel motif being most predictive of activity biases. We explore properties of this cis-regulatory change, revealing the role of particular retroelements, uncovering broad clusters of species-biased enhancers near genes associated with human facial variation, and demonstrating that cis-regulatory divergence is linked to quantitative expression differences of crucial neural crest regulators. Our work provides a wealth of candidates for future evolutionary studies and demonstrates the value of "cellular anthropology," a strategy of using in-vitro-derived embryonic cell types to elucidate both fundamental and evolving mechanisms underlying morphological variation in higher primates.
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Epigenómica/métodos , Evolución Molecular , Mejoramiento Genético , Cresta Neural/citología , Pan troglodytes/genética , Animales , Embrión de Mamíferos/metabolismo , Humanos , Células Madre Pluripotentes Inducidas/metabolismo , Ratones , Ratones Transgénicos , Cresta Neural/metabolismo , Especificidad de la EspecieRESUMEN
Chronic gut inflammatory diseases are associated with disruption of intestinal epithelial barriers and impaired mucosal immunity. HIV-1 (HIV) causes depletion of mucosal CD4+ T cells early in infection and disruption of gut epithelium, resulting in chronic inflammation and immunodeficiency. Although antiretroviral therapy (ART) is effective in suppressing viral replication, it is incapable of restoring the "leaky gut," which poses an impediment for HIV cure efforts. Strategies are needed for rapid repair of the epithelium to protect intestinal microenvironments and immunity in inflamed gut. Using an in vivo nonhuman primate intestinal loop model of HIV/AIDS, we identified the pathogenic mechanism underlying sustained disruption of gut epithelium and explored rapid repair of gut epithelium at the intersection of microbial metabolism. Molecular, immunological, and metabolomic analyses revealed marked loss of peroxisomal proliferator-activated receptor-α (PPARα) signaling, predominant impairment of mitochondrial function, and epithelial disruption both in vivo and in vitro. To elucidate pathways regulating intestinal epithelial integrity, we introduced probiotic Lactobacillus plantarum into Simian immunodeficiency virus (SIV)-inflamed intestinal lumen. Rapid recovery of the epithelium occurred within 5 h of L. plantarum administration, independent of mucosal CD4+ T cell recovery, and in the absence of ART. This intestinal barrier repair was driven by L. plantarum-induced PPARα activation and restoration of mitochondrial structure and fatty acid ß-oxidation. Our data highlight the critical role of PPARα at the intersection between microbial metabolism and epithelial repair in virally inflamed gut and as a potential mitochondrial target for restoring gut barriers in other infectious or gut inflammatory diseases.
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Metabolismo Energético/fisiología , Microbioma Gastrointestinal/fisiología , Intestinos/inmunología , Intestinos/microbiología , Mitocondrias/metabolismo , PPAR alfa/metabolismo , Animales , Terapia Antirretroviral Altamente Activa , Linfocitos T CD4-Positivos/inmunología , Modelos Animales de Enfermedad , Metabolismo Energético/efectos de los fármacos , Epitelio/inmunología , Infecciones por VIH , Humanos , Inmunidad Mucosa , Interleucina-1beta/metabolismo , Intestinos/patología , Lactobacillus plantarum/fisiología , Macaca mulatta , Masculino , Metabolómica , Mitocondrias/efectos de los fármacos , Probióticos/administración & dosificación , Probióticos/uso terapéutico , Síndrome de Inmunodeficiencia Adquirida del Simio/inmunología , Virus de la Inmunodeficiencia de los Simios/inmunologíaRESUMEN
Human cleft lip with or without cleft palate (CL/P) is a common craniofacial abnormality caused by impaired fusion of the facial prominences. We have previously reported that, in the mouse embryo, epithelial apoptosis mediates fusion at the seam where the prominences coalesce. Here, we show that apoptosis alone is not sufficient to remove the epithelial layers. We observed morphological changes in the seam epithelia, intermingling of cells of epithelial descent into the mesenchyme and molecular signatures of epithelial-mesenchymal transition (EMT). Utilizing mouse lines with cephalic epithelium-specific Pbx loss exhibiting CL/P, we demonstrate that these cellular behaviors are Pbx dependent, as is the transcriptional regulation of the EMT driver Snail1. Furthermore, in the embryo, the majority of epithelial cells expressing high levels of Snail1 do not undergo apoptosis. Pbx1 loss- and gain-of-function in a tractable epithelial culture system revealed that Pbx1 is both necessary and sufficient for EMT induction. This study establishes that Pbx-dependent EMT programs mediate murine upper lip/primary palate morphogenesis and fusion via regulation of Snail1. Of note, the EMT signatures observed in the embryo are mirrored in the epithelial culture system.
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Tipificación del Cuerpo/genética , Transición Epitelial-Mesenquimal/genética , Cara/embriología , Morfogénesis/genética , Nariz/embriología , Factor de Transcripción 1 de la Leucemia de Células Pre-B/fisiología , Factores de Transcripción de la Familia Snail/genética , Animales , Apoptosis/genética , Células Cultivadas , Labio Leporino/embriología , Labio Leporino/genética , Fisura del Paladar/embriología , Fisura del Paladar/genética , Embrión de Mamíferos , Cara/anomalías , Regulación del Desarrollo de la Expresión Génica , Labio/embriología , Ratones , Ratones Transgénicos , Hueso Paladar/embriología , Factor de Transcripción 1 de la Leucemia de Células Pre-B/genéticaRESUMEN
3,7-Diazabicyclo[3.3.1]nonane scaffold can serve as a basis for the design of molecular switches stimulating the fast release of water soluble compounds under the influence of external factors from the liposomal containers having those switches incorporated into the lipid bilayer. It was demonstrated that liposomes having 3,7-dihexadecyl-1,5-diphenyl-3,7-diazabicyclo[3.3.1]nonan-9-one (3) incorporated into the liposomal membrane sharply increase the permeability upon pH decrease from 7.4 to 6.5, and compound 3 can serve as a pH-sensitive agent in the bilayer of liposomal nanocontainers. Similar but less pronounced effect was shown for liposomes modified with 3,7-bis(methyldodecylaminoacetyl)-1,5-dimethyl-3,7-diazabicyclo[3.3.1]nonane (5) and 3,7-didodecylsulfonyl-1,5-dimethyl-3,7-diazabicyclo[3.3.1]nonan-9-one (4). The structure (morphology) and size of modified liposomes were studied with scanned transmission electron microscopy.
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Compuestos Aza/química , Compuestos Aza/síntesis química , Membrana Dobles de Lípidos/química , Liposomas/química , Microscopía Electrónica de Transmisión , Estructura MolecularRESUMEN
A novel approach to the synthesis of pH-sensitive prodrugs has been proposed: thiourea drug modification. Resulting prodrugs can release the cytotoxic agent and the biologically active 2-thiohydantoin in the acidic environment of tumor cells. The concept of acid-catalyzed cyclization of thioureas to 2-thiohydantoins has been proven using a FRET model. Dual prodrugs of model azidothymidine, cytotoxic doxorubicin, and 2-thiohydantoin albutoin were obtained, which release the corresponding drugs in the acidic environment. The resulting doxorubicin prodrug was tested on prostate cancer cells and showed that the thiourea-modified prodrug is less cytotoxic (average IC50 ranging from 0.5584 to 0.9885 µM) than doxorubicin (IC50 ranging from 0.01258 to 0.02559 µM) in neutral pH 7.6 and has similar toxicity (average IC50 ranging from 0.4970 to 0.7994 µM) to doxorubicin (IC50 ranging from 0.2303 to 0.8110 µM) under mildly acidic conditions of cancer cells. Cellular and nuclear accumulation in PC3 tumor cells of Dox prodrug is much higher than accumulation of free doxorubicin.
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Antibióticos Antineoplásicos/farmacología , Doxorrubicina/farmacología , Concentración de Iones de Hidrógeno , Profármacos/farmacología , Tiourea/química , Antibióticos Antineoplásicos/química , Línea Celular Tumoral , Doxorrubicina/química , Fluoresceína/química , Transferencia Resonante de Energía de Fluorescencia , Humanos , Masculino , Naftalenos/química , Profármacos/química , Neoplasias de la Próstata/patologíaRESUMEN
Orofacial clefting represents the most common craniofacial birth defect. Cleft lip with or without cleft palate (CL/P) is genetically distinct from cleft palate only (CPO). Numerous transcription factors (TFs) regulate normal development of the midface, comprising the premaxilla, maxilla and palatine bones, through control of basic cellular behaviors. Within the Pbx family of genes encoding Three Amino-acid Loop Extension (TALE) homeodomain-containing TFs, we previously established that in the mouse, Pbx1 plays a preeminent role in midfacial morphogenesis, and Pbx2 and Pbx3 execute collaborative functions in domains of coexpression. We also reported that Pbx1 loss from cephalic epithelial domains, on a Pbx2- or Pbx3-deficient background, results in CL/P via disruption of a regulatory network that controls apoptosis at the seam of frontonasal and maxillary process fusion. Conversely, Pbx1 loss in cranial neural crest cell (CNCC)-derived mesenchyme on a Pbx2-deficient background results in CPO, a phenotype not yet characterized. In this study, we provide in-depth analysis of PBX1 and PBX2 protein localization from early stages of midfacial morphogenesis throughout development of the secondary palate. We further establish CNCC-specific roles of PBX TFs and describe the developmental abnormalities resulting from their loss in the murine embryonic secondary palate. Additionally, we compare and contrast the phenotypes arising from PBX1 loss in CNCC with those caused by its loss in the epithelium and show that CNCC-specific Pbx1 deletion affects only later secondary palate morphogenesis. Moreover, CNCC mutants exhibit perturbed rostro-caudal organization and broadening of the midfacial complex. Proliferation defects are pronounced in CNCC mutants at gestational day (E)12.5, suggesting altered proliferation of mutant palatal progenitor cells, consistent with roles of PBX factors in maintaining progenitor cell state. Although the craniofacial skeletal abnormalities in CNCC mutants do not result from overt patterning defects, osteogenesis is delayed, underscoring a critical role of PBX factors in CNCC morphogenesis and differentiation. Overall, the characterization of tissue-specific Pbx loss-of-function mouse models with orofacial clefting establishes these strains as unique tools to further dissect the complexities of this congenital craniofacial malformation. This study closely links PBX TALE homeodomain proteins to the variation in maxillary shape and size that occurs in pathological settings and during evolution of midfacial morphology.
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Nervios Craneales/embriología , Proteínas de Homeodominio/fisiología , Hueso Paladar/embriología , Factor de Transcripción 1 de la Leucemia de Células Pre-B/fisiología , Proteínas Proto-Oncogénicas/fisiología , Animales , Fisura del Paladar/genética , Nervios Craneales/metabolismo , Femenino , Ratones , Ratones Transgénicos , Hueso Paladar/metabolismo , EmbarazoRESUMEN
BACKGROUND: Risk assessment of sudden cardiac death (SCD) is multifactorial and complex, especially among individuals without established cardiovascular disease. There are insufficiently investigated conditions that can affect arrhythmogenesis. One such condition is obstructive sleep apnea (OSA) syndrome, which is not on the list of risk factors of the Russian National Society of Arrhythmology. OBJECTIVE: The aim of this review article is to discuss clues to the pathophysiology of SCD in OSA subjects. METHODS: We searched the literature for data reporting the impact of apnea on arrhythmogenesis. The preferred languages were English and Russian. The most important clinical reports, as well as biochemistry and pathophysiology guides, were selected for inclusion in the review. RESULTS: It was clearly observed in the searched literature that OSA is the crucial aspect of arrhythmogenesis. Among the clues are intermittent nocturnal hypoxia, reactive oxygen species, cardiomyocyte metabolism disturbances, myocardial electric heterogeneity, and intrathoracic pressure changes. CONCLUSION: This review emphasizes the importance of the inclusion of OSA in the list of risk factors of the Russian National Society of Arrhythmology.
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Arritmias Cardíacas/complicaciones , Arritmias Cardíacas/fisiopatología , Muerte Súbita Cardíaca/etiología , Apnea Obstructiva del Sueño/complicaciones , Apnea Obstructiva del Sueño/fisiopatología , Muerte Súbita Cardíaca/patología , Electrocardiografía , Humanos , Miocardio/metabolismo , Factores de RiesgoRESUMEN
HIV causes rapid CD4+ T cell depletion in the gut mucosa, resulting in immune deficiency and defects in the intestinal epithelial barrier. Breakdown in gut barrier integrity is linked to chronic inflammation and disease progression. However, the early effects of HIV on the gut epithelium, prior to the CD4+ T cell depletion, are not known. Further, the impact of early viral infection on mucosal responses to pathogenic and commensal microbes has not been investigated. We utilized the SIV model of AIDS to assess the earliest host-virus interactions and mechanisms of inflammation and dysfunction in the gut, prior to CD4+ T cell depletion. An intestinal loop model was used to interrogate the effects of SIV infection on gut mucosal immune sensing and response to pathogens and commensal bacteria in vivo. At 2.5 days post-SIV infection, low viral loads were detected in peripheral blood and gut mucosa without CD4+ T cell loss. However, immunohistological analysis revealed the disruption of the gut epithelium manifested by decreased expression and mislocalization of tight junction proteins. Correlating with epithelial disruption was a significant induction of IL-1ß expression by Paneth cells, which were in close proximity to SIV-infected cells in the intestinal crypts. The IL-1ß response preceded the induction of the antiviral interferon response. Despite the disruption of the gut epithelium, no aberrant responses to pathogenic or commensal bacteria were observed. In fact, inoculation of commensal Lactobacillus plantarum in intestinal loops led to rapid anti-inflammatory response and epithelial tight junction repair in SIV infected macaques. Thus, intestinal Paneth cells are the earliest responders to viral infection and induce gut inflammation through IL-1ß signaling. Reversal of the IL-1ß induced gut epithelial damage by Lactobacillus plantarum suggests synergistic host-commensal interactions during early viral infection and identify these mechanisms as potential targets for therapeutic intervention.
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Interleucina-1beta/biosíntesis , Células de Paneth/inmunología , Síndrome de Inmunodeficiencia Adquirida del Simio/inmunología , Animales , Técnica del Anticuerpo Fluorescente , Interacciones Huésped-Parásitos/inmunología , Inmunohistoquímica , Interleucina-1beta/inmunología , Mucosa Intestinal/inmunología , Mucosa Intestinal/ultraestructura , Mucosa Intestinal/virología , Macaca mulatta , Masculino , Microscopía Electrónica de Transmisión , Análisis de Secuencia por Matrices de Oligonucleótidos , Células de Paneth/metabolismo , Células de Paneth/virología , Reacción en Cadena en Tiempo Real de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Uniones Estrechas/ultraestructura , Carga ViralRESUMEN
UNLABELLED: Epithelial barrier dysfunction during human immunodeficiency virus (HIV) infection has largely been attributed to the rapid and severe depletion of CD4(+) T cells in the gastrointestinal (GI) tract. Although it is known that changes in mucosal gene expression contribute to intestinal enteropathy, the role of small noncoding RNAs, specifically microRNA (miRNA), has not been investigated. Using the simian immunodeficiency virus (SIV)-infected nonhuman primate model of HIV pathogenesis, we investigated the effect of viral infection on miRNA expression in intestinal mucosa. SIV infection led to a striking decrease in the expression of mucosal miRNA compared to that in uninfected controls. This decrease coincided with an increase in 5'-3'-exoribonuclease 2 protein and alterations in DICER1 and Argonaute 2 expression. Targets of depleted miRNA belonged to molecular pathways involved in epithelial proliferation, differentiation, and immune response. Decreased expression of several miRNA involved in maintaining epithelial homeostasis in the gut was localized to the proliferative crypt region of the intestinal epithelium. Our findings suggest that SIV-induced decreased expression of miRNA involved in epithelial homeostasis, disrupted expression of miRNA biogenesis machinery, and increased expression of XRN2 are involved in the development of epithelial barrier dysfunction and gastroenteropathy. IMPORTANCE: MicroRNA (miRNA) regulate the development and function of intestinal epithelial cells, and many viruses disrupt normal host miRNA expression. In this study, we demonstrate that SIV and HIV disrupt expression of miRNA in the small intestine during infection. The depletion of several key miRNA is localized to the proliferative crypt region of the gut epithelium. These miRNA are known to control expression of genes involved in inflammation, cell death, and epithelial maturation. Our data indicate that this disruption might be caused by altered expression of miRNA biogenesis machinery during infection. These findings suggest that the disruption of miRNA in the small intestine likely plays a role in intestinal enteropathy during HIV infection.
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VIH , Mucosa Intestinal/metabolismo , Mucosa Intestinal/fisiopatología , Infecciones por Lentivirus/metabolismo , MicroARNs/metabolismo , Virus de la Inmunodeficiencia de los Simios , Adulto , Animales , Secuencia de Bases , Linfocitos T CD4-Positivos/inmunología , Biología Computacional , Densitometría , Citometría de Flujo , Humanos , Mucosa Intestinal/inmunología , Captura por Microdisección con Láser , Infecciones por Lentivirus/fisiopatología , Macaca mulatta , Masculino , Análisis por Micromatrices , Persona de Mediana Edad , Datos de Secuencia Molecular , Reacción en Cadena en Tiempo Real de la Polimerasa , Análisis de Secuencia de ARN , Carga ViralRESUMEN
We have shown previously that during branching morphogenesis of the mouse prostate gland, Bone morphogenetic protein 7 functions to restrict Notch1-positive progenitor cells to the tips of the prostate buds. Here, we employed prostate-specific murine bi-genic systems to investigate the effects of gain and loss of Notch function during prostate development. We show that Nkx3.1(Cre) and Probasin(Cre) alleles drive expression of Cre recombinase to the prostate epithelium and periepithelial stroma. We investigated the effects of gain of Notch function using the Rosa(NI1C) conditional allele, which carries a constitutively active intracellular domain of Notch1 receptor. We carried out the analysis of loss of Notch function in Nkx3.1(Cre/+);RBP-J(flox/flox) prostates, where RBP-J is a ubiquitous transcriptional mediator of Notch signaling. We found that gain of Notch function resulted in inhibition of the tumor suppressor PTEN, and increase in cell proliferation and progenitor cells in the basal epithelium and smooth muscle compartments. In turn, loss of Notch/RBP-J function resulted in decreased cell proliferation and loss of epithelial and smooth muscle progenitors. Gain of Notch function resulted in an early onset of benign prostate hyperplasia by three months of age. Loss of Notch function also resulted in abnormal differentiation of the prostate epithelium and stroma. In particular, loss of Notch signaling and increase in PTEN promoted a switch from myoblast to fibroblast lineage, and a loss of smooth muscle. In summary, we show that Notch signaling is necessary for terminal differentiation of the prostate epithelium and smooth muscle, and that during normal prostate development Notch/PTEN pathway functions to maintain patterned progenitors in the epithelial and smooth muscle compartments. In addition, we found that both positive and negative modulation of Notch signaling results in abnormal organization of the prostate tissue, and can contribute to prostate disease in the adult organ.
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Músculo Liso/embriología , Próstata/embriología , Próstata/metabolismo , Transducción de Señal , Animales , Diferenciación Celular , Proliferación Celular , Supervivencia Celular , Epitelio/embriología , Epitelio/metabolismo , Femenino , Proteínas de Homeodominio/fisiología , Proteína de Unión a la Señal Recombinante J de las Inmunoglobulinas/fisiología , Masculino , Ratones , Fosfohidrolasa PTEN/fisiología , Fosforilación , Próstata/citología , Proteínas Proto-Oncogénicas c-akt/metabolismo , Receptores Notch/fisiología , Factores de Transcripción/fisiologíaRESUMEN
Signaling by Bone morphogenetic proteins (Bmps) has multiple and diverse roles in patterning and morphogenesis of the kidney, eye, limbs and the neural tube. Here, we employed the Bmp7(lacZ) strain to perform a detailed analysis of Bmp7 expression and the null phenotype during development of the mouse urogenital system. The urethral compartment originates in mid-embryogenesis from the ventral part of the cloaca, a transient cavity at the caudal end of the hindgut. At mid-gestation, Bmp7 expression was detected within several specific domains in the cloacal epithelium and mesenchyme. In late embryogenesis, Bmp7 expression was present in the urethra, rectum, the urethral glands, corpus cavernosum, and in the male and female genital ducts. Importantly, loss of Bmp7 resulted in arrest in cloacal septation, and severe defects in morphogenesis of the genital urethra and mesenchyme. Together, our analysis of Bmp7 expression and the null phenotype, indicates that Bmp7 may play an important role in re-organization of the epithelium during cloacal septation and morphogenesis of the genital tubercle.
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Proteína Morfogenética Ósea 7/genética , Regulación del Desarrollo de la Expresión Génica , Uretra/metabolismo , Sistema Urogenital/metabolismo , Animales , Proteína Morfogenética Ósea 7/fisiología , Cloaca/embriología , Cloaca/metabolismo , Embrión de Mamíferos/embriología , Embrión de Mamíferos/metabolismo , Epitelio/embriología , Epitelio/metabolismo , Femenino , Perfilación de la Expresión Génica , Genotipo , Hibridación in Situ , Masculino , Mesodermo/metabolismo , Ratones , Ratones Noqueados , Fenotipo , Factores de Tiempo , Uretra/embriología , Sistema Urogenital/embriologíaRESUMEN
BACKGROUND: The small intestinal epithelium mediates vital functions of nutrient absorption and host defense. The spatial organization of the epithelial cells along the crypt-villus axis segregates them into regions of specialized function. However, the differences in transcriptional programming and the molecular machinery that governs the migration, adhesion, and differentiation of intestinal epithelial cell lineages in humans remain under-explored. To increase our understanding of these mechanisms, we have evaluated gene expression patterns of ileal epithelial cells isolated by laser capture microdissection from either the villus epithelial or crypt cell regions of healthy human small intestinal mucosa. Expression profiles in villus and crypt epithelium were determined by DNA microarray, quantitative real-time PCR, and immunohistochemistry based methods. The expression levels of selected epithelial biomarkers were also compared between gastrointestinal tissues. RESULTS: Previously established biomarkers as well as a novel and distinct set of genes believed to be linked to epithelial cell motility, adhesion, and differentiation were found to be enriched in each of the two corresponding cell populations (GEO accession: GSE10629). Additionally, high baseline expression levels of innate antimicrobials, alpha defensin 5 (HD5) and regenerating islet-derived 3 alpha (Reg3A), were detected exclusively within the small bowel crypt, most notably in the ileum in comparison to other sites along the gastrointestinal tract. CONCLUSION: The elucidation of differential gene expression patterns between crypt and villus epithelial cell lineages in human ileal tissue provides novel insights into the molecular machinery that mediates their functions and spatial organization. Moreover, our findings establish an important framework of knowledge for future investigations of human gastrointestinal diseases.
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Células Epiteliales/metabolismo , Perfilación de la Expresión Génica , Íleon/citología , Íleon/metabolismo , Mucosa Intestinal/metabolismo , Adhesión Celular , Diferenciación Celular , Movimiento Celular , Humanos , Mucosa Intestinal/citología , Análisis de Secuencia por Matrices de Oligonucleótidos , Proteínas Asociadas a PancreatitisRESUMEN
HIV-1 disease progression is paradoxically characterized by systemic chronic immune activation and gut mucosal immune dysfunction, which is not fully defined. Annexin A1 (ANXA1), an inflammation modulator, is a potential link between systemic inflammation and gut immune dysfunction during the simian immunodeficiency virus (SIV) infection. Gene expression of ANXA1 and cytokines were assessed in therapy-naïve rhesus macaques during early and chronic stages of SIV infection and compared with SIV-negative controls. ANXA1 expression was suppressed in the gut but systemically increased during early infection. Conversely, ANXA1 expression increased in both compartments during chronic infection. ANXA1 expression in peripheral blood was positively correlated with HLA-DR+CD4+ and CD8+ T-cell frequencies, and negatively associated with the expression of pro-inflammatory cytokines and CCR5. In contrast, the gut mucosa presented an anergic cytokine profile in relation to ANXA1 expression. In vitro stimulations with ANXA1 peptide resulted in decreased inflammatory response in PBMC but increased activation of gut lymphocytes. Our findings suggest that ANXA1 signaling is dysfunctional in SIV infection, and may contribute to chronic inflammation in periphery and with immune dysfunction in the gut mucosa. Thus, ANXA1 signaling may be a novel therapeutic target for the resolution of immune dysfunction in HIV infection.
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Anexina A1/biosíntesis , Tracto Gastrointestinal/patología , Inmunidad Mucosa , Síndrome de Inmunodeficiencia Adquirida del Simio/patología , Virus de la Inmunodeficiencia de los Simios/inmunología , Animales , Citocinas/biosíntesis , Perfilación de la Expresión Génica , Macaca mulatta , Virus de la Inmunodeficiencia de los Simios/crecimiento & desarrolloRESUMEN
Crohn's disease (CD) is a chronic inflammatory bowel disease typified by transmural inflammation affecting any part of the gastrointestinal tract. CD4(+)CD25(+) regulatory T cells (T(reg) cells) play important roles in intestinal homeostasis. Adoptive transfer of regulatory T cells into mice with chronic colitis prevented inflammation and reappearance of normal intestinal architecture. The Foxp3 gene encodes a protein that is a member of the forkhead/winged-helix family of transcriptional regulators and is involved in the regulation of T cell activation. Mutation of Foxp3 gene may lead to development of autoimmune disease and inflammatory bowel disease. We investigated 10 single-nucleotide polymorphisms (SNPs) of the Foxp3 gene in CD patients and assessed allele and genotype frequencies in 93 patients with Crohn's disease (61 female and 32 male), 82 patients with primary biliary cirrhosis (PBC) (all female), and 108 normal controls (51 female and 57 male). We found that 3 SNPs (-6054, -/ATT; -3279, A/C; -924, A/G) in the promoter region and 1 SNP (IVS9+459, T/C) in the intron 9 region existed in CD patients. No significant differences of allele and genotype frequencies of all four SNPs were observed between CD patients and controls (both female and male groups). However, there was a significance difference of the comparison between PBC patients and controls in the IVS9+459 SNP. These data indicate that SNPs of the Foxp3 gene are not significantly associated with CD but are associated with PBC.
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Enfermedad de Crohn/genética , Factores de Transcripción Forkhead/genética , Femenino , Frecuencia de los Genes , Humanos , Masculino , Polimorfismo de Nucleótido Simple , Linfocitos T Reguladores/fisiologíaRESUMEN
Notch signaling in tumorigenesis and cancer progression presents a certain enigma. Numerous experimental studies reported significant effects in cancer, yet of varying magnitude and opposite sign. This mini review is aimed to streamline our understanding of the Notch role in tumor progression, and outline future experiments to clarify the modality of Notch function and perspectives of the Notch-based anticancer treatments.
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As the "baby boomers" age, the percentage of the population over sixty-five years of age is increasing rapidly. Chronic disease management is an important component in the care of the elderly. The effects of aging on different organ systems are also pertinent; such as the weakening homeostatic response to injury in the older individuals. Mucosal surfaces have the largest combined surface area in the body and are the site of important host microbe interactions, especially in the gut which is prone to injury, both from local and systemic insult. This susceptibility has been known to increase with age. Therefore it is important to understand the interplay between aging, injury and recovery at the mucosal surface. Sex hormones play an important role in the maintenance of the mucosal barrier function as well as the mucosa associated immune function in both genders. Menopause in women is a defined time period in which major hormonal changes occur such as a decline in systemic estradiol levels. The differential levels of sex hormones contribute to the sexual dimorphism seen in response to injury at the mucosal surface, prior to and following menopause. Thus the effect of sex hormone and aging on mucosal mechanisms in response to injury is an important area of investigation.
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OBJECTIVE: The human intestine harbors trillions of commensal microbes that live in homeostasis with the host immune system. Changes in the composition and complexity of gut microbial communities are seen in inflammatory bowel disease (IBD), indicating disruption in host-microbe interactions. Multiple factors including diet and inflammatory conditions alter the microbial complexity. The goal of this study was to develop an optimized methodology for fecal sample processing and to detect changes in the gut microbiota of patients with Crohn's disease receiving specialized diets. DESIGN: Fecal samples were obtained from patients with Crohn's disease in a pilot diet crossover trial comparing the effects of a specific carbohydrate diet (SCD) versus a low residue diet (LRD) on the composition and complexity of the gut microbiota and resolution of IBD symptoms. The gut microbiota composition was assessed using a high-density DNA microarray PhyloChip. RESULTS: DNA extraction from fecal samples using a column based method provided consistent results. The complexity of the gut microbiome was lower in IBD patients compared to healthy controls. An increased abundance of Bacteroides fragilis (B. fragilis) was observed in fecal samples from IBD positive patients. The temporal response of gut microbiome to the SCD resulted in an increased microbial diversity while the LRD diet was associated with reduced diversity of the microbial communities. CONCLUSION: Changes in the composition and complexity of the gut microbiome were identified in response to specialized carbohydrate diet. The SCD was associated with restructuring of the gut microbial communities.
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BACKGROUND: Women and men have diverse responses to many infectious diseases. These differences are amplified following menopause. However, despite extensive information regarding the effects of sex hormones on immune cells, our knowledge is limited regarding the effects of sex and gender on the function of the mucosal immune system. Sex differences also manifest in the prevalence of gut associated inflammatory and autoimmune disorders, including Crohn's disease, ulcerative colitis and Celiac disease. It is thus hypothesized that a baseline sex-associated difference in immune activation may predispose women to inflammation-associated disease. METHODS: Peripheral blood samples and small intestinal biopsies were obtained from 34 healthy men and women. Immunophenotypic analysis of isolated lymphocytes was performed by flow cytometry. Oligonucleotide analysis was used to study the transcriptional profile in the gut mucosal microenvironment while real-time PCR analysis was utilized to identify differential gene expression in isolated CD4+ T cells. Transcriptional analysis was confirmed by protein expression levels for genes of interest using fluorescent immunohistochemistry. Data was analyzed using the GraphPad software package. RESULTS: Women had higher levels of immune activation and inflammation-associated gene expression in gut mucosal samples. CD4+ and CD8+ T cells had a significantly higher level of immune activation-associated phenotype in peripheral blood as well as in gut associated lymphoid tissue along with higher levels of proliferating T cells. CD4+ T cells that showed upregulation of IL1ß as well as the TH17 pathway-associated genes contributed a large part of the inflammatory profile. CONCLUSION: In this study, we demonstrated an upregulation in gene expression related to immune function in the gut microenvironment of women compared to men, in the absence of disease or pathology. Upon closer investigation, CD4+ T cell activation levels were higher in the LPLs in women than in men. Sex differences in the mucosal immune system may predispose women to inflammation-associated diseases that are exacerbated following menopause. Our study highlights the need for more detailed analysis of the effects of sex differences in immune responses at mucosal effector sites.
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BACKGROUND: Development of inflammatory bowel disease (IBD) involves the interplay of environmental and genetic factors with the host immune system. Mechanisms contributing to immune dysregulation in IBD are not fully defined. Development of novel therapeutic strategies is focused on controlling aberrant immune response in IBD. Current IBD therapy utilizes a combination of immunomodulators and biologics to suppress pro-inflammatory effectors of IBD. However, the role of immunomodulatory factors such as annexin A1 (ANXA1) is not well understood. The goal of this study was to examine the association between ANXA1 and IBD, and the effects of anti-TNF-α, Infliximab (IFX), therapy on ANXA1 expression. METHODS: ANXA1 and TNF-α transcript levels in PBMC were measured by RT PCR. Clinical follow up included the administration of serial ibdQs. ANXA1 expression in the gut mucosa was measured by IHC. Plasma ANXA1 levels were measured by ELISA. RESULTS: We found that the reduction in ANXA1 protein levels in plasma coincided with a decrease in the ANXA1 mRNA expression in peripheral blood of IBD patients. ANXA1 expression is upregulated during IFX therapy in patients with a successful intervention but not in clinical non-responders. The IFX therapy also modified the cellular immune activation in the peripheral blood of IBD patients. Decreased expression of ANXA1 was detected in the colonic mucosa of IBD patients with incomplete resolution of inflammation during continuous therapy, which correlated with increased levels of TNF-α transcripts. Gut mucosal epithelial barrier disruption was evident by increased plasma bacterial 16S levels. CONCLUSION: Loss of ANXA1 expression may support inflammation during IBD and can serve as a biomarker of disease progression. Changes in ANXA1 levels may be predictive of therapeutic efficacy.