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The initiation of tissue remodeling following damage is a critical step in preventing the development of immune-mediated diseases. Several factors contribute to mucosal healing, leading to innovative therapeutic approaches for managing intestinal disorders. However, uncovering alternative targets and gaining mechanistic insights are imperative to enhance therapy efficacy and broaden its applicability across different intestinal diseases. Here we demonstrate that Nmes1, encoding for Normal Mucosa of Esophagus-Specific gene 1, also known as Aa467197, is a novel regulator of mucosal healing. Nmes1 influences the macrophage response to the tissue remodeling cytokine IL-4 in vitro. In addition, using two murine models of intestinal damage, each characterized by a type 2-dominated environment with contrasting functions, the ablation of Nmes1 results in decreased intestinal regeneration during the recovery phase of colitis, while enhancing parasitic egg clearance and reducing fibrosis during the advanced stages of Schistosoma mansoni infection. These outcomes are associated with alterations in CX3CR1+ macrophages, cells known for their wound-healing potential in the inflamed colon, hence promising candidates for cell therapies. All in all, our data indicate Nmes1 as a novel contributor to mucosal healing, setting the basis for further investigation into its potential as a new target for the treatment of colon-associated inflammation.
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Colitis , Mucosa Intestinal , Animales , Ratones , Colitis/tratamiento farmacológico , Citocinas , Intestinos , Cicatrización de HeridasRESUMEN
BACKGROUND: Although urological specialist practices are central pillars of outpatient care, there is a lack of current data on the care structure of these practices. A description of the structures in large cities versus rural areas as well as gender effects and generational differences is needed not only as a baseline measure for further studies. MATERIALS AND METHODS: The survey includes data from the physician directory of the Stiftung Gesundheit as well as from the German Medical Association and the Federal Statistical Office. Colleagues were divided into subgroups. Based on the different subgroup sizes, statements about the care structure of outpatient urology in Germany can be made. RESULTS: While the majority of urologists in larger cities work in professional practice groups and care for fewer patients on average, in rural areas there is a particularly high proportion of individual practices with more inhabitants to be cared for per urologist. Female urologists work more frequently in the context of inpatient care. When female urology specialists choose to establish themselves, they are more likely to do so in practice groups and in urban areas. In addition, there is a shift in gender distribution: the younger the age subgroup considered, the higher the proportion of female urologists among all colleagues. CONCLUSIONS: This study is the first to describe the current structure of outpatient urology care in Germany. Future trends are already emerging that will significantly influence our way of working and the care of patients in the coming years.
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Pacientes Ambulatorios , Enfermedades Urológicas , Instituciones de Atención Ambulatoria , Equidad de Género , Alemania , Práctica de Grupo , Enfermedades Urológicas/diagnóstico , Enfermedades Urológicas/terapia , Urólogos , Urología , Humanos , Masculino , Femenino , Adulto , Persona de Mediana EdadRESUMEN
Context: Humanity is facing significant challenges, and in 2019, a new coronavirus caused an unprecedented global disease outbreak. The coronavirus disease 2019 (COVID-19) pandemic vastly impacted health care delivery, generating devastating economic, social, and public health disruption. Although previously underutilized, it was not until recently that telemedicine emerged and amassed tremendous popularity. Objective: To examine and assess telemedicine's past, present, and future roles in urology. Evidence acquisition: We queried relevant literature investigating the role of telemedicine in urology using the electronic PubMed database and mainly focused on English-language studies of any design. Evidence synthesis: Growing attention has been paid to the widespread adoption of novel telehealth technologies for managing various diseases. Meanwhile, solid evidence supports the meaningful use of telemedicine for most urological diagnoses. Existing literature delineates telemedicine as a viable, safe, and convenient alternative to in-person clinical visits. Conclusions: The present article overviews the evolution of telemedicine in urology, and discusses its application in outpatient and physician's office settings. In addition, it highlights the technical, legal, ethical, and financial aspects of telemedicine while providing valuable insights and practical considerations for the future of telehealth in urology. Patient summary: Urologists must adopt telemedicine carefully in daily practice, always adhering to predefined regulatory frameworks.
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Histaminergic (HA) neurons are located in the tuberomamillary nucleus (TMN) of the posterior hypothalamus, from where they project throughout the whole brain to control wakefulness. We examined the effects of Nα-oleoylhistamine (OLHA), a non-enzymatic condensation product of oleic acid (OLA) and histamine, on activity of mouse HA neurons in brain slices. OLHA bidirectionally modulated the firing of HA neurons. At 10 nM OLHA inhibited or had no action, whereas at 1 µM it evoked excitatory and inhibitory responses. Inhibition was not seen in presence of the histamine receptor H3 (H3R) antagonist clobenpropit and in calcium-free medium. Pre-incubation with a histamine-reuptake blocker prevented the decrease in firing by OLHA. OLHA-evoked increase in firing (EC50 â¼44 nM) was insensitive to blockers of cannabinoid 1 and 2 receptors and of the capsaicin receptor, but was significantly impaired by the peroxisome proliferator-activated receptor-alpha (PPAR-alpha) antagonist MK886, which suppressed also the rise in intracellular calcium level caused by OLHA. The OLHA-evoked excitation was mimicked by synthetic PPAR-alpha agonists (gemfibrozil and GW7647) and was abolished by the PKA inhibitor H-89. The H3R affinity (Ki) for histamine, measured in HEK293 cells with stable expression of human H3R, was higher than for OLHA (Ki: 42 vs 310 nM, respectively). Expression of PPAR-alpha was not different between TMN regions of males and females, responses to OLHA did not differ. Molecular modelling of PPAR-alpha bound to either OLHA or OEA showed similar binding energies. These findings shed light on a novel biotransformation product of histamine which may play a role in health and disease.
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Histamina , Receptores Histamínicos H3 , Animales , Encéfalo/metabolismo , Femenino , Células HEK293 , Histamina/metabolismo , Humanos , Masculino , Ratones , Neuronas , Receptores Activados del Proliferador del Peroxisoma/metabolismo , Receptores Histamínicos H3/metabolismoRESUMEN
In the care for patients with urological diseases, outpatient urology secures a near-to-home treatment by specialists in urology and is located between general practitioner and urological clinic. Comparably little is known about the structure and fields of work in this area of urology. A survey of the EAU Section ESUO of outpatient and office urology ( https://uroweb.org/section/esuo/ ) shows the diversity in terms of content and organisation of this sector in Europe, in which more than 16,500 outpatient urologists and thus about half of all professional urologists work full-time. This diversity is related to the diagnostic and therapeutic methods in outpatient urology and to the working conditions of outpatient urologists. For comparison, this information about European countries is contrasted with data from the German office urology as one type of outpatient urology.
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Enfermedades Urológicas , Urología , Europa (Continente) , Humanos , Pacientes Ambulatorios , Enfermedades Urológicas/diagnóstico , Enfermedades Urológicas/terapia , UrólogosRESUMEN
PURPOSE: The present study aimed to investigate how patients identify a quality urologist in primary health care and how they determine and evaluate their provider's qualities before their first examination. PATIENTS AND METHODS: A specific questionnaire (The ESUO Questionnaire) was prepared to describe the domains that influence the patient's evaluation and summarize the urologist related characteristics and behaviours that the patients estimate are more important. A total of 335 patients, over 18 years of age, presented in primary healthcare urology practice, completed the survey. The participants were divided into three age groups; 18-39 years of age (111 patients), 40-59 years of age (111 patients) and 113 patients 60 years of age and older. RESULTS: The majority of patients (68.4%) selected that the urologist must be efficient and well trained. This attitude was primarily expressed in patients ≥60 years of age. Individuals under 60 years old stated that they expect a detailed examination and that the patient should be the urologist's priority. The majority of the patients evaluates friends or family's proposals concerning the urologist's quality primarily and believes that there is at least good quality of urological health care. CONCLUSION: Most patients evaluate primarily the effectiveness of the care they receive instead of the urologist's personality traits or personal relationships.
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AIMS: Histamine H3 receptor (H3R) antagonists/inverse agonists increase vigilance. We studied brain histaminergic pathways under hyperammonemia and the transcriptome of receptors and their signaling cascades to provide a rationale for wake-promoting therapies. METHODS: We analyzed histamine-induced long-lasting depression of corticostriatal synaptic transmission (LLDhist). As the expression of dopamine 1 receptors (D1R) is upregulated in LGS-KO striatum where D1R-H3R dimers may exist, we investigated actions of H3R and D1R agonists and antagonists. We analyzed transcription of selected genes in cortex and dorsal striatum in a mouse model of inborn hyperammonemia (liver-specific glutamine synthetase knockout: LGS-KO) and compared it with human hepatic encephalopathy. RESULTS: LGS-KO mice showed significant reduction of the direct depression (DD) but not the long-lasting depression (LLD) by histamine. Neither pharmacological activation nor inhibition of D1R significantly affected DDhist and LLDhist in WT striatum, while in LGS-KO mice D1R activation suppressed LLDhist. Histaminergic signaling was found unchanged at the transcriptional level except for the H2R. A study of cAMP-regulated genes indicated a significant reduction in the molecular signature of wakefulness in the diseased cortex. CONCLUSIONS: Our findings provide a rationale for the development of aminergic wake-promoting therapeutics in hyperammonemic disorders.
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Corteza Cerebral/metabolismo , Cuerpo Estriado/metabolismo , Histamina/uso terapéutico , Hiperamonemia/tratamiento farmacológico , Hiperamonemia/metabolismo , Plasticidad Neuronal/fisiología , Animales , Corteza Cerebral/efectos de los fármacos , Cuerpo Estriado/efectos de los fármacos , Expresión Génica , Histamina/farmacología , Agonistas de los Receptores Histamínicos/farmacología , Agonistas de los Receptores Histamínicos/uso terapéutico , Antagonistas de los Receptores Histamínicos H3/farmacología , Hiperamonemia/genética , Masculino , Ratones , Ratones Noqueados , Vías Nerviosas/efectos de los fármacos , Vías Nerviosas/fisiología , Plasticidad Neuronal/efectos de los fármacos , Técnicas de Cultivo de ÓrganosRESUMEN
Schistosomes control inflammation in their hosts via highly effective mechanisms such as induction of Tregs, Bregs, and alternatively activated macrophages (AAMs). Notably, IPSE/alpha-1, the major secretory product from Schistosoma mansoni eggs, triggers basophils to release interleukin (IL)-4 and IL-13. Both cytokines are essential for AAM induction, suggesting an important role for IPSE/alpha-1 in inflammation control. Here, we show by in vitro co-culture experiments that IPSE/alpha-1-induced basophil IL-4/IL-13 inhibited pro-inflammatory cytokine release from human LPS-activated monocytes. This effect was cell/cell contact-independent but dependent on IL-4, since it was abrogated in the presence of anti-IL-4 antibodies. Importantly, the IPSE/alpha-1-induced IL-4/IL-13 release from basophils was amplified in the presence of LPS. Moreover, monocytes co-cultured in the presence of LPS with IPSE/alpha-1-stimulated basophils adopted an AAM-like phenotype as assessed by elevated expression of CD206 and CD209. The putative in vivo relevance of these findings was supported by immunohistological staining of S. mansoni-infected murine tissue revealing close physical contact between IPSE/alpha-1 and basophils in schistosome egg granulomas. Taken together, we found that IPSE/alpha-1 dampens inflammatory cytokine responses by triggering basophil IL-4/IL-13, in particular in the context of TLR activation, thereby turning inflammatory monocytes into anti-inflammatory AAMs. This might represent a mechanism used by schistosomes to control inflammation in the host.
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Antígenos Helmínticos/inmunología , Basófilos/inmunología , Basófilos/metabolismo , Citocinas/metabolismo , Mediadores de Inflamación/metabolismo , Schistosoma mansoni/inmunología , Esquistosomiasis mansoni/inmunología , Animales , Humanos , Inmunoglobulina E/inmunología , Interleucina-13/metabolismo , Interleucina-4/metabolismo , Ratones , Monocitos/inmunología , Monocitos/metabolismo , Proteínas Recombinantes/metabolismo , Esquistosomiasis mansoni/parasitologíaRESUMEN
Histaminergic (HA) neurons located in the tuberomamillary nucleus (TMN) of the posterior hypothalamus fire exclusively during waking and support many physiological functions. We investigated the role of the endovanilloid N-oleoyldopamine (OLDA) in TMN, where dopamine synthesis and its conjugation with oleic acid likely occur. We show that several known targets of OLDA including TRPV1 and cannabinoid receptors are expressed in HA neurons. In contrast to capsaicin, which failed to increase firing of HA neurons in TRPV1 knockout mice (TRPVI KO), OLDA was still able to induce excitation. This excitation was not sensitive to the blockade of cannabinoid receptors 1 and 2 and could result from OLDA interaction with GPR119, as the ligand of GPR119, oleoylethanolamide (OEA), also increased the firing of HA neurons. However, we ruled out this possibility as OEA- (but not OLDA-) excitation was abolished by the PPAR (peroxisome proliferator activated receptor) alpha antagonist MK886. The dopamine uptake blocker nomifensine blanked OLDA-excitation and dopamine receptor antagonists abolished the OLDA action in TRPV1 KO mice. Therefore OLDA excites HA neurons through multiple targets suggesting a central role of the histaminergic system in the behavioral stimulation seen after systemic OLDA application.
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Dopamina/análogos & derivados , Histamina/metabolismo , Área Hipotalámica Lateral/efectos de los fármacos , Neuronas/efectos de los fármacos , Neurotransmisores/farmacología , Animales , Dopamina/farmacología , Área Hipotalámica Lateral/citología , Área Hipotalámica Lateral/crecimiento & desarrollo , Área Hipotalámica Lateral/metabolismo , Potenciales de la Membrana/efectos de los fármacos , Potenciales de la Membrana/fisiología , Ratones Endogámicos C57BL , Ratones Transgénicos , Neuronas/citología , Neuronas/metabolismo , Técnicas de Placa-Clamp , Canales Catiónicos TRPV/genética , Canales Catiónicos TRPV/metabolismo , Técnicas de Cultivo de TejidosRESUMEN
After more than 40 years of use, Praziquantel (PZQ) still remains the drug of choice for the treatment of intestinal and urogenital schistosomiasis. Its anti-parasitic activity resides primarily in the (R)-enantiomer. Hitherto neither the molecular target nor the pharmacokinetic-pharmacodynamic relationship have been fully elucidated. Here we investigated the efficacy and pharmacokinetics of PZQ in the Schistosoma mansoni mouse model to determine the key factors that drive its efficacy. Dose-response studies with racemic PZQ with or without addition of an irreversible pan-cytochrome P450 (CYP) inhibitor, 1-aminobenzotriazole (ABT), were performed. In addition, efficacy of PZQ in the presence of the CYP inducer, dexamethasone (DEX), was determined. Plasma samples were obtained by tail vein bleeding at 4 time points. The (R)-PZQ levels were determined using a LC-MS/MS method. Non-compartmental pharmacokinetic analysis was performed using PKsolver. In addition, experiments using an enhanced in vitro assay were conducted. We found that the use of ABT increased (R)-PZQ plasma exposures in the systemic circulation by ~10 to 20 fold but the latter were not predictive of efficacy. The use of DEX decreased plasma exposures of (R)-PZQ in the systemic circulation by ~10 fold without reducing efficacy. We extrapolated the (R)-PZQ concentrations in mouse portal vein / mesenteric veins from the systemic exposures and found that a free exposure of (R)-PZQ of ~ 20 µM*h in the portal vein was needed to obtain a worm burden reduction >60%. It is suggested that the high (R)-PZQ concentrations available before the hepatic first pass metabolism drive the efficacy against S. mansoni adult worms residing in the mesenteric veins. It is then possible that the current dosing regimen of 40 mg/kg in preventive chemotherapy programs may provide suboptimal concentrations in low-weight patients such as children, due to smaller total amounts of drug administered, and may consequently result in lower cure rates.
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Antihelmínticos/farmacología , Antihelmínticos/farmacocinética , Praziquantel/farmacología , Praziquantel/farmacocinética , Schistosoma mansoni/efectos de los fármacos , Esquistosomiasis mansoni/tratamiento farmacológico , Animales , Antihelmínticos/administración & dosificación , Quimioprevención/métodos , Cromatografía Liquida , Dexametasona/administración & dosificación , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Activadores de Enzimas/administración & dosificación , Inhibidores Enzimáticos/administración & dosificación , Ratones , Plasma/química , Praziquantel/administración & dosificación , Esquistosomiasis mansoni/prevención & control , Espectrometría de Masas en Tándem , Factores de Tiempo , Triazoles/administración & dosificaciónRESUMEN
N-oleoyl-dopamine (OLDA) is an amide of dopamine and oleic acid, synthesized in catecholaminergic neurons. The present study investigates OLDA targets in midbrain dopaminergic (DA) neurons. Substantia Nigra compacta (SNc) DA neurons recorded in brain slices were excited by OLDA in wild type mice. In transient receptor potential vanilloid 1 (TRPV1) knockout (KO) mice, however, SNc DA neurons displayed sustained inhibition of firing. In the presence of the dopamine type 2 receptor (D2R) antagonist sulpiride or the dopamine transporter blocker nomifensine no such inhibition was observed. Under sulpiride OLDA slightly excited SNc DA neurons, an action abolished upon combined application of the cannabinoid1 and 2 receptor antagonists AM251 and AM630. In ventral tegmental area (VTA) DA neurons from TRPV1 KO mice a transient inhibition of firing by OLDA was observed. Thus OLDA modulates the firing of nigrostriatal DA neurons through interactions with TRPV1, cannabinoid receptors and dopamine uptake. These findings suggest further development of OLDA-like tandem molecules for the treatment of movement disorders including Parkinson's disease.
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Dopaminérgicos/farmacología , Dopamina/análogos & derivados , Neuronas Dopaminérgicas/efectos de los fármacos , Mesencéfalo/citología , Canales Catiónicos TRPV/metabolismo , Acrilamidas/farmacología , Potenciales de Acción/efectos de los fármacos , Factores de Edad , Animales , Animales Recién Nacidos , Compuestos Bicíclicos Heterocíclicos con Puentes/farmacología , Antagonistas de Receptores de Cannabinoides/farmacología , Dopamina/farmacología , Proteínas de Transporte de Dopamina a través de la Membrana Plasmática/genética , Proteínas de Transporte de Dopamina a través de la Membrana Plasmática/metabolismo , Proteínas Luminiscentes/genética , Proteínas Luminiscentes/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Inhibición Neural/efectos de los fármacos , Técnicas de Placa-Clamp , Piperidinas/farmacología , Pirazoles/farmacología , Canales Catiónicos TRPV/antagonistas & inhibidores , Canales Catiónicos TRPV/genética , Tirosina 3-Monooxigenasa/metabolismoRESUMEN
Genetic defects in ammonia metabolism can produce irreversible damage of the developing CNS causing an impairment of cognitive and motor functions. We investigated alterations in behavior, synaptic plasticity and gene expression in the hippocampus and dorsal striatum of transgenic mice with systemic hyperammonemia resulting from conditional knockout of hepatic glutamine synthetase (LGS-ko). These mice showed reduced exploratory activity and delayed habituation to a novel environment. Field potential recordings from LGS-ko brain slices revealed significantly reduced magnitude of electrically-induced long-term potentiation (LTP) in both CA3-CA1 hippocampal and corticostriatal synaptic transmission. Corticostriatal but not hippocampal slices from LGS-ko brains demonstrated also significant alterations in long-lasting effects evoked by pharmacological activation of glutamate receptors. Real-time RT-PCR revealed distinct patterns of dysregulated gene expression in the hippocampus and striatum of LGS-ko mice: LGS-ko hippocampus showed significantly modified expression of mRNAs for mGluR1, GluN2B subunit of NMDAR, and A1 adenosine receptors while altered expression of mRNAs for D1 dopamine receptors, the M1 cholinoreceptor and the acetylcholine-synthetizing enzyme choline-acetyltransferase was observed in LGS-ko striatum. Thus, inborn systemic hyperammonemia resulted in significant deficits in novelty acquisition and disturbed synaptic plasticity in corticostriatal and hippocampal pathways involved in learning and goal-directed behavior.
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Encéfalo/fisiopatología , Conducta Exploratoria , Glutamato-Amoníaco Ligasa/deficiencia , Hiperamonemia/genética , Hiperamonemia/psicología , Plasticidad Neuronal , Animales , Encéfalo/metabolismo , Corteza Cerebral/fisiopatología , Cuerpo Estriado/metabolismo , Cuerpo Estriado/fisiopatología , Glutamato-Amoníaco Ligasa/genética , Habituación Psicofisiológica , Hipocampo/metabolismo , Hipocampo/fisiopatología , Hiperamonemia/congénito , Hígado/metabolismo , Masculino , Ratones Noqueados , Receptores de Dopamina D2/fisiología , Receptores de N-Metil-D-Aspartato/fisiología , Transmisión SinápticaRESUMEN
Using a reporter mouse model with expression of the tomato fluorescent protein under the dopamine transporter promoter (Tmt-DAT) we discovered a new group of neurons in the histaminergic tuberomamillary nucleus (TMN), which, in contrast to tuberoinfundibular dopaminergic neurons of the dorsomedial arcuate nucleus, do not express tyrosine hydroxylase but can synthesize and store dopamine. Tmt-DAT neurons located within TMN share electrophysiological properties with histaminergic neurons: spontaneous firing at a membrane potential around -50 mV and presence of hyperpolarization-activated cyclic nucleotide-gated ion channels. Histamine (30 µM) depolarizes and excites Tmt-DAT neurons through H1R activation but inhibits histaminergic neurons through H3R activation thus allowing a pharmacological identification of the different neurons. Single-cell RT-PCR revealed that all histaminergic neurons expressing histidine decarboxylase (HDC) also express H3R. This includes neurons retrogradely traced from the striatum whose inhibition by a selective H3R agonist was indistinguishable from the whole population. Prolonged depolarization reduces the autoinhibition. The potency of histamine at H3R depends on membrane potential and on extracellular and intracellular calcium. Autoinhibition can be impaired by preincubation with capsaicin, a ligand of the calcium-permeable TRPV1 channel or by blockade of Ca(2+)-ATPase with thapsigargin. The pharmacology of autoinhibition is revisited and physiological conditions for its functionality are determined. Usage of reporter mouse models for the safe identification of aminergic neurons under pathophysiological conditions is recommended. This article is part of the Special Issue entitled 'Histamine Receptors'.
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Histamina/metabolismo , Área Hipotalámica Lateral/citología , Área Hipotalámica Lateral/metabolismo , Neuronas/citología , Neuronas/metabolismo , Receptores Histamínicos H3/metabolismo , Animales , Calcio/metabolismo , ATPasas Transportadoras de Calcio/metabolismo , Proteínas de Transporte de Dopamina a través de la Membrana Plasmática/genética , Proteínas de Transporte de Dopamina a través de la Membrana Plasmática/metabolismo , Femenino , Histidina Descarboxilasa/metabolismo , Área Hipotalámica Lateral/efectos de los fármacos , Masculino , Potenciales de la Membrana/efectos de los fármacos , Potenciales de la Membrana/fisiología , Ratones Endogámicos C57BL , Ratones Transgénicos , Inhibición Neural/efectos de los fármacos , Inhibición Neural/fisiología , Neuronas/efectos de los fármacos , Receptores Histamínicos H1/metabolismo , Canales Catiónicos TRPV/metabolismo , Técnicas de Cultivo de TejidosRESUMEN
During the complex lifecycle of Schistosoma mansoni, a large variety of glycans is expressed. To many of these glycans, antibodies are induced by the infected host and some might be targets for vaccines or diagnostic tests. Spatial changes in glycan expression during schistosome development are largely unexplored. To study the surface-exposed glycans during the important initial stages of infection, we analyzed the binding of a panel of anti-glycan monoclonal antibodies (mAbs) to cercariae and schistosomula up to 72 h after transformation by immunofluorescence microscopy. The mAb specificity toward their natural targets was studied using a microarray containing a wide range of schistosomal N-glycans, O-glycans and glycosphingolipid glycans. With the exception of GalNAcß1-4(Fucα1-3)GlcNAc (LDN-F), mono- and multifucosylated GalNAcß1-4GlcNAc (LDN)-motifs were exposed at the surface of all developmental stages studied. Multifucosylated LDN-motifs were present on cercarial glycocalyx-derived O-glycans as well as cercarial glycolipids. In contrast, the Galß1-4(Fucα1-3)GlcNAc (Lewis X) and LDN-F-motifs, also expressed on cercarial glycolipids, and in addition on a range of cercarial N- and O-glycans, became surface expressed only after transformation of cercariae to schistosomula. In line with the documented shedding of the O-glycan-rich cercarial glycocalyx after transformation these observations suggest that surface accessible multifucosylated LDN-motifs are mostly expressed by O-glycans in cercariae, but principally by glycosphingolipids in schistosomula. We hypothesize that these temporal changes in surface exposure of glycan antigens are relevant to the interaction with the host during the initial stages of infection with schistosomes and discuss the potential of these glycan antigens as intervention targets.
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Cercarias/inmunología , Glicocálix/inmunología , Polisacáridos/inmunología , Schistosoma mansoni/inmunología , Animales , Anticuerpos Antihelmínticos/inmunología , Anticuerpos Monoclonales/inmunología , Schistosoma mansoni/crecimiento & desarrolloRESUMEN
The T2 ribonuclease omega-1 is a powerful Th2-inducing factor secreted by the eggs of the blood fluke Schistosoma mansoni. Omega-1 can modulate pattern recognition receptor-induced inflammatory signatures and alter antigen presentation by dendritic cells. Recent findings have suggested that component(s) contained in or secreted by S. mansoni eggs (soluble egg antigen) can also enhance IL-1ß secretion by dendritic cells stimulated with pattern recognition receptor ligands. Here we show that omega-1 enhances IL-1ß secretion in macrophages stimulated with Toll-like receptor 2 ligand, and propose omega-1 as the factor in soluble egg antigen capable of regulating inflammasome activity. This effect is dependent on the C-type lectin receptor Dectin-1, caspase-8 and the ASC inflammasome adaptor protein, highlighting the ability of omega-1 to regulate multiple pattern recognition receptor signalling pathways. These mechanistic insights into manipulation of host immunity by a parasite product have implications for the design of anti-inflammatory therapeutic drugs.
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Antígenos Helmínticos/metabolismo , Proteínas del Huevo/metabolismo , Endorribonucleasas/inmunología , Inflamasomas/inmunología , Interleucina-1beta/inmunología , Macrófagos Peritoneales/inmunología , Schistosoma mansoni/inmunología , Animales , Caspasa 8/metabolismo , Células Dendríticas/inmunología , Células Dendríticas/metabolismo , Endorribonucleasas/metabolismo , Humanos , Inflamasomas/metabolismo , Interleucina-1beta/metabolismo , Lectinas Tipo C/inmunología , Lectinas Tipo C/metabolismo , Macrófagos Peritoneales/metabolismo , Ratones , Schistosoma mansoni/enzimología , Células Th2/inmunologíaRESUMEN
The IL-4-inducing principle from Schistosoma mansoni eggs (IPSE/α-1), the major secretory product of eggs from the parasitic worm S. mansoni, efficiently triggers basophils to release the immunomodulatory key cytokine interleukin-4. Activation by IPSE/α-1 requires the presence of IgE on the basophils, but the detailed molecular mechanism underlying activation is unknown. NMR and crystallographic analysis of IPSEΔNLS, a monomeric IPSE/α-1 mutant, revealed that IPSE/α-1 is a new member of the ßγ-crystallin superfamily. We demonstrate that this molecule is a general immunoglobulin-binding factor with highest affinity for IgE. NMR binding studies of IPSEΔNLS with the 180-kDa molecule IgE identified a large positively charged binding surface that includes a flexible loop, which is unique to the IPSE/α-1 crystallin fold. Mutational analysis of amino acids in the binding interface showed that residues contributing to IgE binding are important for IgE-dependent activation of basophils. As IPSE/α-1 is unable to cross-link IgE, we propose that this molecule, by taking advantage of its unique IgE-binding crystallin fold, activates basophils by a novel, cross-linking-independent mechanism.
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Antígenos Helmínticos/metabolismo , Basófilos/metabolismo , Cristalinas/inmunología , Proteínas del Huevo/metabolismo , Proteínas del Helminto/metabolismo , Inmunoglobulina E/metabolismo , Secuencia de Aminoácidos , Animales , Antígenos Helmínticos/química , Antígenos Helmínticos/genética , Sitios de Unión/genética , Western Blotting , Cromatografía en Gel , Cristalinas/genética , Cristalinas/metabolismo , Cristalografía por Rayos X , Proteínas del Huevo/química , Proteínas del Huevo/genética , Proteínas del Helminto/química , Proteínas del Helminto/genética , Humanos , Inmunoglobulina E/química , Interleucina-4/metabolismo , Espectroscopía de Resonancia Magnética , Modelos Moleculares , Datos de Secuencia Molecular , Mutación , Unión Proteica , Mapeo de Interacción de Proteínas , Estructura Secundaria de Proteína , Estructura Terciaria de Proteína , Schistosoma mansoni/genética , Schistosoma mansoni/metabolismo , Homología de Secuencia de AminoácidoRESUMEN
Histamine is a developmentally highly conserved autacoid found in most vertebrate tissues. Its physiological functions are mediated by four 7-transmembrane G protein-coupled receptors (H1R, H2R, H3R, H4R) that are all targets of pharmacological intervention. The receptors display molecular heterogeneity and constitutive activity. H1R antagonists are long known antiallergic and sedating drugs, whereas the H2R was identified in the 1970s and led to the development of H2R-antagonists that revolutionized stomach ulcer treatment. The crystal structure of ligand-bound H1R has rendered it possible to design new ligands with novel properties. The H3R is an autoreceptor and heteroreceptor providing negative feedback on histaminergic and inhibition on other neurons. A block of these actions promotes waking. The H4R occurs on immuncompetent cells and the development of anti-inflammatory drugs is anticipated.
Asunto(s)
Diseño de Fármacos , Histamina/metabolismo , Receptores Histamínicos/efectos de los fármacos , Animales , Agonistas de los Receptores Histamínicos/farmacología , Antagonistas de los Receptores Histamínicos/farmacología , Humanos , Ligandos , Receptores Histamínicos/metabolismoRESUMEN
BACKGROUND: Schistosomiasis is a serious health problem especially in developing countries and affects more than 243 million people. Only few anthelmintic drugs are available up to now. A major obstacle for drug treatment is the different developmental stages and the varying host compartments during worm development. Anthelmintic drugs have been tested mainly on adult schistosomes or freshly transformed cercariae. Knowledge concerning the larval stages is lacking. METHODOLOGY/PRINCIPAL FINDINGS: In this study, we used in vitro-grown schistosomula (aged between 2 to 14 days) to investigate drug effects of the three anthelmintics praziquantel, artemether, and oxamniquine. Further, we analyzed the antibody accessibility of two exemplary schistosome antigens SmCD59a and SmKK7, before and after drug treatment. Our results demonstrated that praziquantel applied at a concentration of 1 µM inhibited development of all life stages. Application of 10 µM praziquantel led to dramatic morphological changes of all schistosomula. Artemether at 1 and 10 µM had differential effects depending on whether it was applied to 2-day as compared to 7- and 14-day schistosomula. While 2-day schistosomula were not killed but inhibited from further development, severe morphological damage was seen in 7- and 14-day schistosomula. Oxamniquine (1 and 10 µM) led to severe morphological impairment in all life stages. Analyzing the accessibility of the antigens SmCD59a and SmKK7 before drug treatment showed no antibody binding on living intact schistosomula. However, when schistosomula were treated with anthelmintics, both antigens became exposed on the larvae. Oxamniquine turned out to be most effective in promoting antibody binding to all schistosomula stages. CONCLUSION: This study has revealed marked differences in anthelmintic drug effects against larvae. Drug treatment increases surface antigen presentation and renders larvae accessible to antibody attack.