The neuromodulator oxytocin, since its first synthesis by du Vigneaud in 1953, has mainly been associated with beneficial physiological effects, as well as positive social and emotional behaviors. ...This overall positive picture of oxytocin as the "love-, cuddle-, or bonding-hormone" has repeatedly been challenged since then. Oxytocin-induced effects that would be perceived as negative by the individual, such as increased anxiety or potentiation of stress-induced ACTH release, as well as the regulation of negative approach-related emotions, such as envy and schadenfreude (gloating) have been described. The general consent is that oxytocin, instead of acting unidirectional, induces changes in the salience network to shift the emphasis of emotional contexts, and therefore can, e.g., produce both anxiolytic as well as anxiogenic behavioral outcomes. However, the underlying mechanisms leading to alterations in the salience network are still unclear. With the aim to understand the manifold effects of oxytocin on a cellular/molecular level, a set of oxytocin receptor-coupled signaling cascades and downstream effectors regulating transcription and translation has been identified. Those oxytocin-driven effectors, such as MEF2 and CREB, are known modulators of the neuronal and glial cytoarchitecture. We hypothesize that, by determining cellular morphology and connectivity, MEF2 is one of the key factors that might contribute to the diverse behavioral effects of oxytocin.
Various single nucleotide polymorphisms (SNPs) in the oxytocin receptor (OXTR) gene have been associated with behavioral traits, autism spectrum disorder (ASD) and other diseases. The non-synonymous ...SNP rs4686302 results in the OXTR variant A218T and has been linked to core characteristics of ASD, trait empathy and preterm birth. However, the molecular and intracellular mechanisms underlying those associations are still elusive. Here, we uncovered the molecular and intracellular consequences of this mutation that may affect the psychological or behavioral outcome of oxytocin (OXT)-treatment regimens in clinical studies, and provide a mechanistic explanation for an altered receptor function. We created two monoclonal HEK293 cell lines, stably expressing either the wild-type or A218T OXTR. We detected an increased OXTR protein stability, accompanied by a shift in Ca
dynamics and reduced MAPK pathway activation in the A218T cells. Combined whole-genome and RNA sequencing analyses in OXT-treated cells revealed 7823 differentially regulated genes in A218T compared to wild-type cells, including 429 genes being associated with ASD. Furthermore, computational modeling provided a molecular basis for the observed change in OXTR stability suggesting that the OXTR mutation affects downstream events by altering receptor activation and signaling, in agreement with our in vitro results. In summary, our study provides the cellular mechanism that links the OXTR rs4686302 SNP with genetic dysregulations associated with aspects of ASD.
Anthropogenic disturbances and the subsequent loss of biodiversity are altering species abundances and communities. Since species vary in their pathogen competence, spatio-temporal changes in host ...assemblages may lead to changes in disease dynamics. We explore how longitudinal changes in bat species assemblages affect the disease dynamics of coronaviruses (CoVs) in more than 2300 cave-dwelling bats captured over two years from five caves in Ghana. This reveals uneven CoV infection patterns between closely related species, with the alpha-CoV 229E-like and SARS-related beta-CoV 2b emerging as multi-host pathogens. Prevalence and infection likelihood for both phylogenetically distinct CoVs is influenced by the abundance of competent species and naïve subadults. Broadly, bat species vary in CoV competence, and highly competent species are more common in less diverse communities, leading to increased CoV prevalence in less diverse bat assemblages. In line with the One Health framework, our work supports the notion that biodiversity conservation may be the most proactive measure to prevent the spread of pathogens with zoonotic potential.
The neuropeptide oxytocin (OT) is a well-described modulator of socio-emotional traits, such as anxiety, stress, social behavior, and pair bonding. However, when dysregulated, it is associated with ...adverse psychiatric traits, such as various aspects of autism spectrum disorder (ASD). In this study, we identify the transcription factor myocyte enhancer factor 2A (MEF2A) as the common link between OT and cellular changes symptomatic for ASD, encompassing neuronal morphology, connectivity, and mitochondrial function. We provide evidence for MEF2A as the decisive factor defining the cellular response to OT: while OT induces neurite retraction in MEF2A expressing neurons, OT causes neurite outgrowth in absence of MEF2A. A CRISPR-Cas-mediated knockout of MEF2A and retransfection of an active version or permanently inactive mutant, respectively, validated our findings. We also identified the phosphatase calcineurin as the main upstream regulator of OT-induced MEF2A signaling. Further, MEF2A signaling dampens mitochondrial functioning in neurons, as MEF2A knockout cells show increased maximal cellular respiration, spare respiratory capacity, and total cellular ATP. In summary, we reveal a central role for OT-induced MEF2A activity as major regulator of cellular morphology as well as neuronal connectivity and mitochondrial functioning, with broad implications for a potential treatment of disorders based on morphological alterations or mitochondrial dysfunction.
The absence of the yeast protein seripauperin 5 (PAU5) from Saccharomyces cerevisiae has been suggested as a biomarker for the occurrence of gushing in sparkling wine as samples lacking PAU5 were ...found to be more susceptible to gushing. In this study, further characterization of PAU5 regarding its foam-stabilizing properties was performed to elucidate whether PAU5 has foam-stabilizing properties and therefore, to elucidate a direct influence on the gushing potential of sparkling wines. PAU5 was successfully purified from non-gushing sparkling wine using reversed-phase high-performance liquid chromatography (RP-HPLC). Pure protein was added to grape juice as a model system for grape must prior to foam stability testing. The results revealed that the protein PAU5 has foam-stabilizing properties. Furthermore, the influence of heat and sulfur treatment in the presence of Botrytis cinerea was analyzed with regard to the amount of PAU5 produced by S. cerevisiae fermented in grape juice. Fermentation experiments using two different S. cerevisiae strains were performed, and the concentration of PAU5 in the samples was compared by RP-HPLC analysis. Unlike sulfur treatment, heat treatment prevented the protein degradation induced by B. cinerea and resulted in even higher amounts of PAU5 compared to the juice fermented with yeast without a previous botrytization. The two different yeast strains applied secreted PAU5 into the surrounding medium in different amounts. In further experiments, the fining process of the wine with bentonite was examined for its potential to remove PAU5 from the wine. RP-HPLC of wines processed with different fining agents revealed that bentonite treatment affected PAU5 concentrations in the final product. The extent of PAU5 removal depended on the type of bentonite applied and on the time of addition during the production process.
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•The yeast protein PAU5 has foam stabilizing properties.•Bentonite treatment was shown to have an influence on the amount of PAU5 in wine.•Temperature treatment of botrytized prevents PAU5 degradation in infected model musts.
Oxytocin (OT) has gained attention not only as anxiolytic drug and as potential treatment option for autistic children; it also acts as a growth and differentiation factor in neuronal cells. While ...behavioral effects of OT have been studied in detail, knowledge about the cellular effects of OT is relatively sparse. In this study, we present evidence for three hypotheses: 1) OT leads to neurite retraction in hypothalamic neurons via the OT receptor (OTR) 2) The transcription factor MEF-2A is a central regulator of OT-induced neurite retraction, and 3) The MAPK pathway is critical for OT-induced MEF-2A activation.
Incubation of rat hypothalamic H32 cells with 10 nM to 1 μM OT, vasopressin, and the specific OTR agonist TGOT, over the course of 12 h resulted in a time-dependent, significant retraction of neurites. In addition, the size of the nuclear compartment increased, whereas the overall cell size remained unchanged. OT treatment for 10 h increased the cellular viability significantly, and this effect could be blocked by a specific OTR antagonist, providing evidence for a specific and pro-active effect of OT on neurite retraction, and not as an unspecific side effect of apoptosis.
The molecular mechanism that controls OT-induced neurite retraction includes a reduced phosphorylation of the transcription factor MEF-2A at Serine 408 (S408). This dephosphorylation is under the control of the OTR-coupled MAPK pathway, as blocking MEK1/2 by U0126 inhibited MEF-2A activation and subsequent neurite retraction. The siRNA-mediated knockdown of MEF-2A prevented the OT-induced neurite retraction, providing direct evidence for a role of MEF-2A in morphological alterations induced by OT treatment.
In summary, the present study reveals a previously unknown OTR-coupled MAPK-MEF-2A pathway, which is responsible for OT-induced neurite retraction of hypothalamic neurons.
•OT leads to neurite retraction in hypothalamic neurons via the OT receptor (OTR).•The transcription factor MEF-2A is a central regulator of OT-induced neurite retraction.•The MAPK pathway is critical for OT-induced MEF-2A activation.
Cities’ green areas are fragmented patches and are often confined to smaller sizes than the higher built-up proportions. Such small-sized green areas can be essential components of green ...infrastructure to compensate for biodiversity loss. As a proxy to biodiversity, we studied birds in nine small green area locations of Freiburg and eight area locations in Regensburg in Germany. We investigated the neighboring green networks (distance to the nearest water body and another green area) and landscape metrics (patch abundance and habitat heterogeneity at a 1 km radius) that might benefit and explain bird richness and composition in small green areas. We found that the variations in the observed species richness and composition at the surveyed locations were better explained solely by green networks in Freiburg and by green networks and landscape metrics in Regensburg. In general, it indicates that a small green area could be biodiverse if its spatial distribution considers a nearby water body and other green areas, allowing a higher abundance of similar patches and habitat heterogeneity in the neighborhood.
The neuropeptide oxytocin (OXT) has generated considerable interest as potential treatment for psychiatric disorders, including anxiety and autism spectrum disorders. However, the behavioral and ...molecular consequences associated with chronic OXT treatment and chronic receptor (OXTR) activation have scarcely been studied, despite the potential therapeutic long-term use of intranasal OXT. Here, we reveal that chronic OXT treatment over two weeks increased anxiety-like behavior in rats, with higher sensitivity in females, contrasting the well-known anxiolytic effect of acute OXT. The increase in anxiety was transient and waned 5 days after the infusion has ended. The behavioral effects of chronic OXT were paralleled by activation of an intracellular signaling pathway, which ultimately led to alternative splicing of hypothalamic corticotropin-releasing factor receptor 2α (Crfr2α), an important modulator of anxiety. In detail, chronic OXT shifted the splicing ratio from the anxiolytic membrane-bound (mCRFR2α) form of CRFR2α towards the soluble CRFR2α (sCRFR2α) form. Experimental induction of alternative splicing mimicked the anxiogenic effects of chronic OXT, while sCRFR2α-knock down reduced anxiety-related behavior of male rats. Furthermore, chronic OXT treatment triggered the release of sCRFR2α into the cerebrospinal fluid with sCRFR2α levels positively correlating with anxiety-like behavior. In summary, we revealed that the shifted splicing ratio towards expression of the anxiogenic sCRFR2α underlies the adverse effects of chronic OXT treatment on anxiety.
Background
Obsessive compulsive disorder (OCD) is a psychiatric disorder which has been shown to affect 2 to 3.5% of people during their lifetimes. Inadequate response occurs in 40% to 60% of people ...that are prescribed first line pharmaceutical treatments (selective serotonin reuptake inhibitors (SSRIs)). To date not much is known about the efficacy and adverse effects of second‐generation antipsychotic drugs (SGAs) in people suffering from OCD.
Objectives
To evaluate the effects of SGAs (monotherapy or add on) compared with placebo or other forms of pharmaceutical treatment for people with OCD.
Search methods
The Cochrane Depression, Anxiety and Neurosis Group's controlled trial registers (CCDANCTR‐Studies and CCDANCTR‐References) were searched up to 21 July 2010. The author team ran complementary searches on ClinicalTrials.gov and contacted key authors and drug companies.
Selection criteria
We included double‐blind randomised controlled trials (RCTs) comparing oral SGAs (monotherapy or add on) in adults with other forms of pharmaceutical treatment or placebo in people with primary OCD.
Data collection and analysis
We extracted data independently. For dichotomous data we calculated the odds ratio (OR) and their 95% confidence intervals (CI) on an intention‐to‐treat basis based on a random‐effects model. For continuous data, we calculated mean differences (MD), again based on a random‐effects model.
Main results
We included 11 RCTs with 396 participants on three SGAs. All trials investigated the effects of adding these SGAs to antidepressants (usually SSRIs). The duration of all trials was less than six months. Only 13% of the participants left the trials early. Most trials were limited in terms of quality aspects.
Two trials examined olanzapine and found no difference in the primary outcome (response to treatment) and most other efficacy‐related outcomes but it was associated with more weight gain than monotherapy with antidepressants.
Quetiapine combined with antidepressants was also not any more efficacious than placebo combined with antidepressants in terms of the primary outcome, but there was a significant superiority in the mean Yale‐Brown Obsessive Compulsive Scale (Y‐BOCS) score at endpoint (MD ‐2.28, 95% CI ‐4.05 to ‐0.52). There were also some beneficial effects of quetiapine in terms of anxiety or depressive symptoms.
Risperidone was more efficacious than placebo in terms of the primary outcome (number of participants without a significant response) (OR 0.17, 95% CI 0.04 to 0.66) and in the reduction of anxiety and depression (MD ‐7.60, 95% CI ‐12.37 to ‐2.83).
Authors' conclusions
The available data of the effects of olanzapine in OCD are too limited to draw any conclusions. There is some evidence that adding quetiapine or risperidone to antidepressants increases efficacy, but this must be weighed against less tolerability and limited data.
Understanding the immunogenetic basis of coronavirus (CoV) susceptibility in major pathogen reservoirs, such as bats, is central to inferring their zoonotic potential. Members of the cryptic ...Hipposideros bat species complex differ in CoV susceptibility, but the underlying mechanisms remain unclear. The genes of the major histocompatibility complex (MHC) are the best understood genetic basis of pathogen resistance, and differences in MHC diversity are one possible reason for asymmetrical infection patterns among closely related species. Here, we aimed to link asymmetries in observed CoV (CoV‐229E, CoV‐2B and CoV‐2Bbasal) susceptibility to immunogenetic differences amongst four Hipposideros bat species. From the 2072 bats assigned to their respective species using the mtDNA cytochrome b gene, members of the most numerous and ubiquitous species, Hipposideros caffer D, were most infected with CoV‐229E and SARS‐related CoV‐2B. Using a subset of 569 bats, we determined that much of the existent allelic and functional (i.e. supertype) MHC DRB class II diversity originated from common ancestry. One MHC supertype shared amongst all species, ST12, was consistently linked to susceptibility with CoV‐229E, which is closely related to the common cold agent HCoV‐229E, and infected bats and those carrying ST12 had a lower body condition. The same MHC supertype was connected to resistance to CoV‐2B, and bats with ST12 were less likely be co‐infected with CoV‐229E and CoV‐2B. Our work suggests a role of immunogenetics in determining CoV susceptibility in bats. We advocate for the preservation of functional genetic and species diversity in reservoirs as a means of mitigating the risk of disease spillover.
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