ABSTRACT
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.
Subject(s)
Colitis , Intestinal Mucosa , Animals , Mice , Colitis/drug therapy , Cytokines , Intestines , Wound HealingABSTRACT
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.
Subject(s)
Drug Design , Histamine/metabolism , Receptors, Histamine/drug effects , Animals , Histamine Agonists/pharmacology , Histamine Antagonists/pharmacology , Humans , Ligands , Receptors, Histamine/metabolismABSTRACT
Humoral immunity requires cross-talk between T follicular helper (Tfh) cells and B cells. Nevertheless, a detailed understanding of this intercellular interaction during secondary immune responses is lacking. We examined this by focusing on the response to a soluble, unadjuvanted, pathogen-derived Ag (soluble extract of Schistosoma mansoni egg [SEA]) that induces type 2 immunity. We found that activated Tfh cells persisted for long periods within germinal centers following primary immunization. However, the magnitude of the secondary response did not appear to depend on pre-existing Tfh cells. Instead, Tfh cell populations expanded through a process that was dependent on memory T cells recruited into the reactive LN, as well as the participation of B cells. We found that, during the secondary response, IL-4 was critical for the expansion of a population of plasmablasts that correlated with increased SEA-specific IgG1 titers. Additionally, following immunization with SEA (but not with an Ag that induced type 1 immunity), IL-4 and IL-21 were coproduced by individual Tfh cells, revealing a potential mechanism through which appropriate class-switching can be coupled to plasmablast proliferation to enforce type 2 immunity. Our findings demonstrate a pivotal role for IL-4 in the interplay between T and B cells during a secondary Th2 response and have significant implications for vaccine design.
Subject(s)
B-Lymphocytes/immunology , B-Lymphocytes/metabolism , Cell Communication/immunology , Immunologic Memory , Interleukin-4/metabolism , T-Lymphocytes, Helper-Inducer/immunology , T-Lymphocytes, Helper-Inducer/metabolism , Animals , Antigens/immunology , Antigens, Helminth/immunology , B-Lymphocytes/cytology , Cell Differentiation/immunology , Immunization , Immunophenotyping , Interleukins/biosynthesis , Lymph Nodes/metabolism , Lymphocyte Depletion , Mice , Mice, Transgenic , Phenotype , Plasma Cells/cytology , Plasma Cells/immunology , Plasma Cells/metabolism , Schistosoma mansoni/immunology , T-Lymphocyte Subsets/immunology , T-Lymphocyte Subsets/metabolism , T-Lymphocytes, Helper-Inducer/cytologyABSTRACT
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.
Subject(s)
Antigens, Helminth/metabolism , Basophils/metabolism , Crystallins/immunology , Egg Proteins/metabolism , Helminth Proteins/metabolism , Immunoglobulin E/metabolism , Amino Acid Sequence , Animals , Antigens, Helminth/chemistry , Antigens, Helminth/genetics , Binding Sites/genetics , Blotting, Western , Chromatography, Gel , Crystallins/genetics , Crystallins/metabolism , Crystallography, X-Ray , Egg Proteins/chemistry , Egg Proteins/genetics , Helminth Proteins/chemistry , Helminth Proteins/genetics , Humans , Immunoglobulin E/chemistry , Interleukin-4/metabolism , Magnetic Resonance Spectroscopy , Models, Molecular , Molecular Sequence Data , Mutation , Protein Binding , Protein Interaction Mapping , Protein Structure, Secondary , Protein Structure, Tertiary , Schistosoma mansoni/genetics , Schistosoma mansoni/metabolism , Sequence Homology, Amino AcidABSTRACT
Cyclophilin (Cyp) allergens are considered pan-allergens due to frequently reported cross-reactivity. In addition to well studied fungal Cyps, a number of plant Cyps were identified as allergens (e.g. Bet v 7 from birch pollen, Cat r 1 from periwinkle pollen). However, there are conflicting data regarding their antigenic/allergenic cross-reactivity, with no plant Cyp allergen structures available for comparison. Because amino acid residues are fairly conserved between plant and fungal Cyps, it is particularly interesting to check whether they can cross-react. Cat r 1 was identified by immunoblotting using allergic patients' sera followed by N-terminal sequencing. Cat r 1 (â¼ 91% sequence identity to Bet v 7) was cloned from a cDNA library and expressed in Escherichia coli. Recombinant Cat r 1 was utilized to confirm peptidyl-prolyl cis-trans-isomerase (PPIase) activity by a PPIase assay and the allergenic property by an IgE-specific immunoblotting and rat basophil leukemia cell (RBL-SX38) mediator release assay. Inhibition-ELISA showed cross-reactive binding of serum IgE from Cat r 1-allergic individuals to fungal allergenic Cyps Asp f 11 and Mala s 6. The molecular structure of Cat r 1 was determined by NMR spectroscopy. The antigenic surface was examined in relation to its plant, animal, and fungal homologues. The structure revealed a typical cyclophilin fold consisting of a compact ß-barrel made up of seven anti-parallel ß-strands along with two surrounding α-helices. This is the first structure of an allergenic plant Cyp revealing high conservation of the antigenic surface particularly near the PPIase active site, which supports the pronounced cross-reactivity among Cyps from various sources.
Subject(s)
Allergens/chemistry , Cyclophilins/chemistry , Pollen/chemistry , Adult , Allergens/immunology , Amino Acid Sequence , Animals , Base Sequence , Blotting, Western , Case-Control Studies , Cell Line, Tumor , Circular Dichroism , Cross Reactions , Cyclophilins/immunology , DNA Primers , DNA, Complementary , Female , Humans , Hypersensitivity/immunology , Magnetic Resonance Spectroscopy , Male , Middle Aged , Models, Molecular , Molecular Sequence Data , Pollen/immunology , Rats , Sequence Homology, Amino Acid , Young AdultABSTRACT
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.
Subject(s)
Cercaria/immunology , Glycocalyx/immunology , Polysaccharides/immunology , Schistosoma mansoni/immunology , Animals , Antibodies, Helminth/immunology , Antibodies, Monoclonal/immunology , Schistosoma mansoni/growth & developmentABSTRACT
Breathing and vigilance are regulated by pH and CO2 levels in the central nervous system. The hypocretin/orexin (Hcrt/Orx)- and histamine (HA)-containing hypothalamic neurons synergistically control different aspects of the waking state. Acidification inhibits firing of most neurons but these two groups in the caudal hypothalamus are excited by hypercapnia and protons, similar to the chemosensory neurons in the brain stem. Activation of hypothalamic wake-on neurons in response to hypercapnia, seen with the c-Fos assay, is supported by patch-clamp recordings in rodent brain slices: Hcrt/Orx and HA neurons are excited by acidification in the physiological range (pH from 7.4 to 7.0). Multiple molecular mechanisms mediate wake-promoting effects of protons in HA neurons in the tuberomamillary nucleus (TMN): among them are acid-sensing ion channels, Na(+),K(+)-ATPase, group I metabotropic glutamate receptors (mGluRI). HA neurons are remarkably sensitive to the mGluRI agonist DHPG (threshold concentration 0.5 µM) and mGluRI antagonists abolish proton-induced excitation of HA neurons. Hcrt/Orx neurons are excited through block of a potassium conductance and release glutamate with their peptides in TMN. The two hypothalamic nuclei and the serotonergic dorsal raphe cooperate toward CO2/acid-induced arousal. Their interactions and molecular mechanisms of H(+)/CO2-induced activation are relevant for the understanding and treatment of respiratory and metabolic disorders related to sleep-waking such as obstructive sleep apnea and sudden infant death syndrome.
Subject(s)
Acid Sensing Ion Channels/metabolism , Action Potentials/physiology , Hypothalamus/metabolism , Neurons/metabolism , Animals , Glutamic Acid/metabolism , Humans , Intracellular Signaling Peptides and Proteins/metabolism , Neuropeptides/metabolism , OrexinsABSTRACT
Recent reports have attributed an immunoregulatory role to the mammalian target of rapamycin (mTOR), a key serine/threonine protein kinase integrating input from growth factors and nutrients to promote cell growth and differentiation. In the present study, we investigated the role of the mTOR pathway in Th2 induction by human monocyte-derived dendritic cells (moDCs). Using a co-culture system of human lipopolysaccharide (LPS)-matured moDCs and allogeneic naive CD4(+) T cells, we show that inhibition of mTOR by the immunosuppressive drug rapamycin reduced moDC maturation and promoted Th2 skewing. Next, we investigated whether antigens from helminth parasites, the strongest natural inducers of Th2 responses, modulate moDCs via the mTOR pathway. In contrast to rapamycin, neither Schistosoma mansoni-soluble egg antigens (SEA) nor its major immunomodulatory component omega-1 affected the phosphorylation of S6 kinase (S6K) and 4E-binding protein 1 (4E-BP1), downstream targets of mTORC1. Finally, we found that the effects of rapamycin and SEA/omega-1 on Th2 skewing were additive, suggesting two distinct underlying molecular mechanisms. We conclude that conditioning human moDCs to skew immune responses towards Th2 can be achieved via an mTOR-dependent and -independent pathway triggered by rapamycin and helminth antigens, respectively.
Subject(s)
CD4-Positive T-Lymphocytes/immunology , Dendritic Cells/immunology , Schistosoma mansoni/immunology , Sirolimus/pharmacology , TOR Serine-Threonine Kinases/metabolism , Adaptor Proteins, Signal Transducing/metabolism , Animals , Antigens, Helminth/immunology , Cell Cycle Proteins , Cell Differentiation/drug effects , Cells, Cultured , Coculture Techniques , Egg Proteins/immunology , Helminth Proteins/immunology , Humans , Isoantigens/immunology , Lipopolysaccharides/immunology , Phosphoproteins/metabolism , Ribosomal Protein S6 Kinases/metabolism , Signal Transduction/drug effects , TOR Serine-Threonine Kinases/immunology , Th1-Th2 Balance/drug effectsABSTRACT
Hyperammonemia is a major pathophysiological factor in encephalopathies associated with acute and chronic liver failure. On mouse brain slice preparations we analyzed the effects of ammonium on the characteristics of corticostriatal long-term potentiation (LTP) induced by high-frequency electrical stimulation (HFS) of cortical input and the long-lasting effects of pharmacological NMDA receptor (NMDAR) activation. Ammonium chloride exposure enhanced the expression of HFS-induced LTP at the expense of LTD and promoted the generation of NMDA-induced LTD. This treatment did not affect two NMDAR-independent forms of plasticity: taurine-induced LTP and histamine-induced LTD. Alterations in NMDA-induced plasticity were prevented by treatment with green tea polyphenols suggesting the contribution of oxidative stress to the expression of abnormal corticostriatal plasticity.
Subject(s)
Antioxidants/pharmacology , Corpus Striatum/drug effects , Corpus Striatum/physiology , Long-Term Synaptic Depression/drug effects , Polyphenols/pharmacology , Quaternary Ammonium Compounds/metabolism , Tea , Animals , Antioxidants/chemistry , Catechin/chemistry , Catechin/pharmacology , Electric Stimulation , Histamine/metabolism , Hyperammonemia/metabolism , Male , Mice , Mice, Inbred C57BL , Polyphenols/chemistry , Receptors, N-Methyl-D-Aspartate/metabolism , Taurine/metabolism , Tea/chemistryABSTRACT
Glycans present on glycoproteins from the eggs of the parasite Schistosoma mansoni are mediators of various immune responses of the human host, including T-cell modulation and granuloma formation, and they are the target of glycan-specific antibodies. Here we have analyzed the glycosylation of kappa-5, a major glycoprotein antigen from S. mansoni eggs using a targeted approach of lectin purification followed by mass spectrometry of glycopeptides as well as released glycans. We demonstrate that kappa-5 has four fully occupied N-glycosylation sites carrying unique triantennary glycans composed of a difucosylated and xylosylated core region, and immunogenic GalNAcß1-4GlcNAc (LDN) termini. Furthermore, we show that the kappa-5 specific IgE antibodies in sera of S. mansoni-infected individuals are directed against the core region of the kappa-5 glycans. Whereas two previously analyzed immunomodulatory egg glycoproteins, IPSE/alpha-1 and omega-1, both express diantennary N-glycans with a difucosylated core and one or two Galß1-4(Fucα1-3)GlcNAc (Lewis X) antennae, the kappa-5 glycosylation appears unique among the major soluble egg antigens of S. mansoni. The distinct structural and antigenic properties of kappa-5 glycans suggest a specific role for kappa-5 in schistosome egg immunogenicity.
Subject(s)
Antibodies, Helminth/blood , Egg Proteins/metabolism , Glycoproteins/metabolism , Helminth Proteins/metabolism , Schistosoma mansoni/metabolism , Schistosomiasis mansoni/blood , Amino Acid Motifs , Animals , Antibodies, Helminth/chemistry , Antigens, Helminth , Egg Proteins/immunology , Glycoproteins/immunology , Glycoside Hydrolases/chemistry , Glycosylation , Helminth Proteins/immunology , Host-Parasite Interactions , Humans , Immunoglobulin E/blood , Immunoglobulin E/chemistry , Lactose/analogs & derivatives , Lactose/immunology , Lactose/metabolism , Peptide Fragments/chemistry , Polysaccharides/chemistry , Schistosoma mansoni/immunology , Schistosomiasis mansoni/immunology , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization , Tandem Mass SpectrometryABSTRACT
BACKGROUND: Little is known about the effect of neuropeptides on basophils, which are important effector cells in immune and allergic responses. OBJECTIVE: This study aimed at revealing the role of α-melanocyte-stimulating hormone (α-MSH) on basophil function. METHODS: Expression of melanocortin receptors and proopiomelanocortin (POMC) was analyzed by means of RT-PCR, Western immunoblotting, fluorescence-activated cell sorting, and double-immunofluorescence analysis. Signal transduction studies included cyclic AMP and Ca(2+) mobilization assays. Basophil activity was assessed based on CD63 surface expression and cytokine release. RESULTS: MC-1R expression was detectable in basophils isolated from human peripheral blood, as well as in basophils within nasal tissue. In isolated basophils from human blood, truncated POMC transcripts were present, but there was no POMC protein. Treatment of basophils with α-MSH increased intracellular Ca(2+) but not cyclic AMP levels. α-MSH at physiologic doses potently suppressed basophil activation induced by N-formyl-methionyl-leucyl-phenylalanine, phorbol 12-myristate 13-acetate, or grass pollen allergen in whole blood of healthy or allergic subjects, respectively. The effect of α-MSH on basophil activation was MC-1R mediated (as shown by blockade with a peptide analogue of agouti-signaling protein) and imitated by adrenocorticotropic hormone but not elicited by the tripeptides KPV and KdPT, both of which lack the central pharmacophore of α-MSH. Moreover, α-MSH at physiologic doses significantly suppressed secretion of 3 proallergic cytokines, IL-4, IL-6, and IL-13, in basophils stimulated with anti-IgE, N-formyl-methionyl-leucyl-phenylalanine, or phorbol 12-myristate 13-acetate. CONCLUSION: Our findings highlight a novel functional activity of α-MSH, which acts as a natural antiallergic basophil-response modifier. These findings might point to novel therapeutic strategies in treating allergic diseases.
Subject(s)
Basophils/drug effects , Basophils/metabolism , alpha-MSH/pharmacology , Allergens/immunology , Basophils/immunology , Calcium Signaling/drug effects , Cell Line , Cyclic AMP/metabolism , Cytokines/metabolism , Humans , N-Formylmethionine Leucyl-Phenylalanine/pharmacology , Pro-Opiomelanocortin/genetics , Receptors, Melanocortin/metabolism , Signal Transduction/drug effects , Transcription, GeneticABSTRACT
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.
Subject(s)
Outpatients , Urologic Diseases , Ambulatory Care Facilities , Gender Equity , Germany , Group Practice , Urologic Diseases/diagnosis , Urologic Diseases/therapy , Urologists , Urology , Humans , Male , Female , Adult , Middle AgedABSTRACT
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.
ABSTRACT
An essential component of the whole-body homoeostasis provided by the hypothalamus is the management of available energy. This includes the regulation of sleeping and waking, feeding and drinking, body temperature and activity, as well as the endocrinium. The waking brain, in particular the cerebral cortex, needs to be activated through neuronal pathways ascending from the brainstem reticular formation (ascending reticular activating system, ARAS) and reaching the cortical structures by a dorsal route through the thalamus and a ventral route, including the hypothalamus and the basal forebrain. This review concentrates on the more recently explored ventral route and the hypothalamus with its different regions involved in the control of the waking state.
Subject(s)
Hypothalamus/physiology , Wakefulness/physiology , Animals , Circadian Rhythm/physiology , Humans , Neurons/physiology , Sleep/physiologyABSTRACT
The histaminergic neurons of the posterior hypothalamus (tuberomamillary nucleus-TMN) control wakefulness, and their silencing through activation of GABA(A) receptors (GABA(A)R) induces sleep and is thought to mediate sedation under propofol anaesthesia. We have previously shown that the ß1 subunit preferring fragrant dioxane derivatives (FDD) are highly potent modulators of GABA(A)R in TMN neurons. In recombinant receptors containing the ß3N265M subunit, FDD action is abolished and GABA potency is reduced. Using rat, wild-type and ß3N265M mice, FDD and propofol, we explored the relative contributions of ß1- and ß3-containing GABA(A)R to synaptic transmission from the GABAergic sleep-on ventrolateral preoptic area neurons to TMN. In ß3N265M mice, GABA potency remained unchanged in TMN neurons, but it was decreased in cultured posterior hypothalamic neurons with impaired modulation of GABA(A)R by propofol. Spontaneous and evoked GABAergic synaptic currents (IPSC) showed ß1-type pharmacology, with the same effects achieved by 3 µM propofol and 10 µM PI24513. Propofol and the FDD PI24513 suppressed neuronal firing in the majority of neurons at 5 and 100 µM, and in all cells at 10 and 250 µM, respectively. FDD given systemically in mice induced sedation but not anaesthesia. Propofol-induced currents were abolished (1-6 µM) or significantly reduced (12 µM) in ß3N265M mice, whereas gating and modulation of GABA(A)R by PI24513 as well as modulation by propofol were unchanged. In conclusion, ß1-containing (FDD-sensitive) GABA(A)R represent the major receptor pool in TMN neurons responding to GABA, while ß3-containing (FDD-insensitive) receptors are gated by low micromolar doses of propofol. Thus, sleep and anaesthesia depend on different GABA(A)R types.
Subject(s)
Anesthesia , Protein Subunits/physiology , Receptors, GABA-A/physiology , Sleep/physiology , Action Potentials/drug effects , Action Potentials/physiology , Animals , Electrophysiological Phenomena/drug effects , Electrophysiological Phenomena/physiology , GABA-A Receptor Agonists/pharmacology , Gene Expression/genetics , Histamine/metabolism , Hypothalamic Area, Lateral/cytology , Hypothalamic Area, Lateral/metabolism , Inhibitory Postsynaptic Potentials/drug effects , Inhibitory Postsynaptic Potentials/physiology , Ion Channel Gating/drug effects , Ion Channel Gating/physiology , Locomotion/drug effects , Male , Mice , Mice, Inbred C57BL , Mice, Mutant Strains , Neurons/cytology , Neurons/drug effects , Neurons/metabolism , Point Mutation/physiology , Propofol/pharmacology , Rats , Rats, Wistar , Receptors, GABA-A/genetics , gamma-Aminobutyric Acid/pharmacologyABSTRACT
Hyperammonemia is a major pathophysiological factor in encephalopathies associated with acute and chronic liver failure. On mouse brain slice preparations, we analyzed the effects of ammonia on the characteristics of corticostriatal long-term depression (LTD) induced by electrical stimulation of cortical input or pharmacological activation of metabotropic glutamate receptors. Long exposure of neostriatal slices to ammonium chloride impaired the induction and/or expression of all studied forms of LTD. This impairment was reversed by the phosphodiesterase inhibitor zaprinast implying lowered cGMP signaling in LTD suppression. Polyphenols from green tea rescued short-term corticostriatal plasticity, but failed to prevent the ammonia-induced deficit of LTD. Zaprinast counteracts the ammonia-induced impairment of long-term corticostriatal plasticity and may thus improve fine motor skills and procedural learning in hepatic encephalopathy.
Subject(s)
Ammonia/pharmacology , Cerebral Cortex/cytology , Corpus Striatum/cytology , Long-Term Synaptic Depression/drug effects , Phosphodiesterase Inhibitors/pharmacology , Purinones/pharmacology , Synapses/drug effects , Animals , Antioxidants/pharmacology , Biophysics , Cerebral Cortex/drug effects , Cerebral Cortex/physiology , Corpus Striatum/drug effects , Corpus Striatum/physiology , Cycloheximide/pharmacology , Drug Interactions , Electric Stimulation , In Vitro Techniques , Male , Methoxyhydroxyphenylglycol/analogs & derivatives , Methoxyhydroxyphenylglycol/pharmacology , Mice , Mice, Inbred C57BL , Polyphenols/pharmacology , Protein Synthesis Inhibitors/pharmacologyABSTRACT
Immunization with Schistosoma mansoni soluble antigen preparations protects non-obese diabetic (NOD) mice against the development of type 1 diabetes. These preparations have long been known to induce Th2 responses in vitro and in vivo. Recently, two separate groups have reported that ω-1, a well-characterized glycoprotein in S. mansoni soluble egg antigens (SEA), which with IL-4 inducing principle of S. mansoni eggs (IPSE/α-1) is one of the two major glycoproteins secreted by live eggs, is a major SEA component responsible for this effect. We found that ω-1 induces Foxp3 as well as IL-4 expression when injected in vivo. We confirmed that ω-1 conditions DCs to drive Th2 responses and further demonstrated that ω-1 induces Foxp3(+) T cells from NOD mouse naïve T cells. In contrast, IPSE/α-1 did not drive Foxp3 responses. The in vitro development of Foxp3-expressing T cells by ω-1 was TGF-ß- and retinoic acid-dependent. Our work, therefore, identifies ω-1 as an important factor for the induction of Foxp3(+) T cells by SEA in NOD mice.
Subject(s)
CD4-Positive T-Lymphocytes/metabolism , Diabetes Mellitus, Type 1/immunology , Forkhead Transcription Factors/metabolism , Interleukin-4/metabolism , Schistosoma mansoni/immunology , Animals , CD4-Positive T-Lymphocytes/drug effects , CD4-Positive T-Lymphocytes/immunology , CD4-Positive T-Lymphocytes/pathology , Cell Differentiation/drug effects , Cells, Cultured , Dendritic Cells/drug effects , Dendritic Cells/immunology , Dendritic Cells/metabolism , Dendritic Cells/pathology , Diabetes Mellitus, Type 1/prevention & control , Egg Proteins/administration & dosage , Forkhead Transcription Factors/genetics , Forkhead Transcription Factors/immunology , Helminth Proteins/administration & dosage , Immunization , Interleukin-4/genetics , Interleukin-4/immunology , Mice , Mice, Inbred BALB C , Mice, Inbred NOD , Schistosoma mansoni/metabolism , Th2 Cells/immunology , Transforming Growth Factor beta/genetics , Transforming Growth Factor beta/metabolism , Tretinoin/metabolismABSTRACT
Genetic ablation of the histamine producing enzyme histidine decarboxylase (HDC) leads to alteration in exploratory behaviour and hippocampus-dependent learning. We investigated how brain histamine deficiency in HDC knockout mice (HDC KO) affects hippocampal excitability, synaptic plasticity, and the expression of histamine receptors. No significant alterations in: basal synaptic transmission, long-term potentiation (LTP) in the Schaffer collateral synapses, histamine-induced transient changes in the CA1 pyramidal cell excitability, and the expression of H1 and H2 receptor mRNAs were found in hippocampal slices from HDC KO mice. However, when compared to WT mice, HDC KO mice demonstrated: 1. a stronger enhancement of LTP by histamine, 2. a stronger impairment of LTP by ammonia, 3. no long-lasting potentiation of population spikes by histamine, 4. a decreased expression of H3 receptor mRNA, and 5. less potentiation of population spikes by H3 receptor agonism. Parallel measurements in the hypothalamic tuberomamillary nucleus, the origin of neuronal histamine, demonstrated an increased expression of H3 receptors in HDC KO mice without any changes in the spontaneous firing of "histaminergic" neurons without histamine and their responses to the H3 receptor agonist (R)-α-methylhistamine. We conclude that the absence of neuronal histamine results in subtle changes in hippocampal synaptic transmission and plasticity associated with alteration in the expression of H3 receptors.
Subject(s)
Ammonia/metabolism , Hippocampus/physiology , Histidine Decarboxylase/genetics , Neuronal Plasticity/genetics , Receptors, Histamine/genetics , Ammonia/blood , Animals , Gene Expression/drug effects , Hippocampus/drug effects , Hippocampus/metabolism , Histamine/pharmacology , Histamine Agonists/pharmacology , Male , Methylhistamines/pharmacology , Mice , Mice, Knockout , Neuronal Plasticity/drug effects , Receptors, Histamine/metabolism , Receptors, Histamine H3/genetics , Receptors, Histamine H3/metabolism , Synaptic Transmission/drug effects , Synaptic Transmission/geneticsABSTRACT
Wakefulness and consciousness depend on perturbation of the cortical soliloquy. Ascending activation of the cerebral cortex is characteristic for both waking and paradoxical (REM) sleep. These evolutionary conserved activating systems build a network in the brainstem, midbrain, and diencephalon that contains the neurotransmitters and neuromodulators glutamate, histamine, acetylcholine, the catecholamines, serotonin, and some neuropeptides orchestrating the different behavioral states. Inhibition of these waking systems by GABAergic neurons allows sleep. Over the past decades, a prominent role became evident for the histaminergic and the orexinergic neurons as a hypothalamic waking center.
Subject(s)
Brain/physiology , Wakefulness/physiology , Animals , Arousal/physiology , Biogenic Monoamines/metabolism , Biogenic Monoamines/physiology , Histamine/metabolism , Histamine/physiology , Humans , Hypothalamus, Posterior/physiology , Models, BiologicalABSTRACT
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.