36 research outputs found
Molecular Sites for the Positive Allosteric Modulation of Glycine Receptors by Endocannabinoids
Glycine receptors (GlyRs) are transmitter-gated anion channels of the Cys-loop superfamily which mediate synaptic inhibition at spinal and selected supraspinal sites. Although they serve pivotal functions in motor control and sensory processing, they have yet to be exploited as drug targets partly because of hitherto limited possibilities for allosteric control. Endocannabinoids (ECs) have recently been characterized as direct allosteric GlyR modulators, but the underlying molecular sites have remained unknown. Here, we show that chemically neutral ECs (e.g. anandamide, AEA) are positive modulators of α1, α2 and α3 GlyRs, whereas acidic ECs (e.g. N-arachidonoyl-glycine; NA-Gly) potentiate α1 GlyRs but inhibit α2 and α3. This subunit-specificity allowed us to identify the underlying molecular sites through analysis of chimeric and mutant receptors. We found that alanine 52 in extracellular loop 2, glycine 254 in transmembrane (TM) region 2 and intracellular lysine 385 determine the positive modulation of α1 GlyRs by NA-Gly. Successive substitution of non-conserved extracellular and TM residues in α2 converted NA-Gly-mediated inhibition into potentiation. Conversely, mutation of the conserved lysine within the intracellular loop between TM3 and TM4 attenuated NA-Gly-mediated potentiation of α1 GlyRs, without affecting inhibition of α2 and α3. Notably, this mutation reduced modulation by AEA of all three GlyRs. These results define molecular sites for allosteric control of GlyRs by ECs and reveal an unrecognized function for the TM3-4 intracellular loop in the allosteric modulation of Cys-loop ion channels. The identification of these sites may help to understand the physiological role of this modulation and facilitate the development of novel therapeutic approaches to diseases such as spasticity, startle disease and possibly chronic pain
Global metabolomic profiling of uterine leiomyomas
Background: Uterine leiomyomas can be classified into molecularly distinct subtypes according to their genetic triggers: MED12 mutations, HMGA2 upregulation, or inactivation of FH. The aim of this study was to identify metabolites and metabolic pathways that are dysregulated in different subtypes of leiomyomas. Methods: We performed global metabolomic profiling of 25 uterine leiomyomas and 17 corresponding myometrium specimens using liquid chromatography-tandem mass spectroscopy. Results: A total of 641 metabolites were detected. All leiomyomas displayed reduced homocarnosine and haeme metabolite levels. We identified a clearly distinct metabolomic profile for leiomyomas of the FH subtype, characterised by metabolic alterations in the tricarboxylic acid cycle and pentose phosphate pathways, and increased levels of multiple lipids and amino acids. Several metabolites were uniquely elevated in leiomyomas of the FH subtype, including N6-succinyladenosine and argininosuccinate, serving as potential biomarkers for FH deficiency. In contrast, leiomyomas of the MED12 subtype displayed reduced levels of vitamin A, multiple membrane lipids and amino acids, and dysregulation of vitamin C metabolism, a finding which was also compatible with gene expression data. Conclusions: The study reveals the metabolomic heterogeneity of leiomyomas and provides the requisite framework for strategies designed to target metabolic alterations promoting the growth of these prevalent tumours.Peer reviewe
Recommended from our members
Search for Joint Multimessenger Signals from Potential Galactic Cosmic-Ray Accelerators with HAWC and IceCube
The origin of high-energy galactic cosmic rays is yet to be understood, but some galactic cosmic-ray accelerators can accelerate cosmic rays up to PeV energies. The high-energy cosmic rays are expected to interact with the surrounding material or radiation, resulting in the production of gamma-rays and neutrinos. To optimize for the detection of such associated production of gamma-rays and neutrinos for a given source morphology and spectrum, a multimessenger analysis that combines gamma-rays and neutrinos is required. In this study, we use the MultiMission Maximum Likelihood framework with IceCube Maximum Likelihood Analysis software and HAWC Accelerated Likelihood to search for a correlation between 22 known gamma-ray sources from the third HAWC gamma-ray catalog and 14 yr of IceCube track-like data. No significant neutrino emission from the direction of the HAWC sources was found. We report the best-fit gamma-ray model and 90% CL neutrino flux limit from the 22 sources. From the neutrino flux limit, we conclude that, for five of the sources, the gamma-ray emission observed by HAWC cannot be produced purely from hadronic interactions. We report the limit for the fraction of gammarays produced by hadronic interactions for these five sources
Single-mode cavities at frequencies of 172 and 178 MHz
In the report presented here the projects of two accelerating cavities with strong damping of higher modes (HOM) with special vacuum loads are presented. The designs of the cavities and loads are described. The design parameters of cavities, their spectra of higher modes and calculation results of the beam phase motion stability are given for the VEPP-2000 and NANOHANA Projects
Author Correction: A multi-country test of brief reappraisal interventions on emotions during the COVID-19 pandemic
In the version of this article initially published, the following authors were omitted from the author list and the Author contributions section for “investigation” and “writing and editing”: Nandor Hajdu (Institute of Psychology, ELTE Eötvös Loránd University, Budapest, Hungary), Jordane Boudesseul (Facultad de Psicología, Instituto de Investigación Científica, Universidad de Lima, Lima, Perú), Rafał Muda (Faculty of Economics, Maria Curie-Sklodowska University, Lublin, Poland) and Sandersan Onie (Black Dog Institute, UNSW Sydney, Sydney, Australia & Emotional Health for All Foundation, Jakarta, Indonesia). In addition, Saeideh FatahModares’ name was originally misspelled as Saiedeh FatahModarres in the author list. Further, affiliations have been corrected for Maria Terskova (National Research University Higher School of Economics, Moscow, Russia), Susana Ruiz Fernandez (FOM University of Applied Sciences, Essen; Leibniz-Institut für Wissensmedien, Tübingen, and LEAD Research Network, Eberhard Karls University, Tübingen, Germany), Hendrik Godbersen (FOM University of Applied Sciences, Essen, Germany), Gulnaz Anjum (Department of Psychology, Simon Fraser University, Burnaby, Canada, and Department of Economics & Social Sciences, Institute of Business Administration, Karachi, Pakistan). The changes have been made to the HTML and PDF versions of the article
A global experiment on motivating social distancing during the COVID-19 pandemic
Significance
Communicating in ways that motivate engagement in social distancing remains a critical global public health priority during the COVID-19 pandemic. This study tested motivational qualities of messages about social distancing (those that promoted choice and agency vs. those that were forceful and shaming) in 25,718 people in 89 countries. The autonomy-supportive message decreased feelings of defying social distancing recommendations relative to the controlling message, and the controlling message increased controlled motivation, a less effective form of motivation, relative to no message. Message type did not impact intentions to socially distance, but people’s existing motivations were related to intentions. Findings were generalizable across a geographically diverse sample and may inform public health communication strategies in this and future global health emergencies.
Abstract
Finding communication strategies that effectively motivate social distancing continues to be a global public health priority during the COVID-19 pandemic. This cross-country, preregistered experiment (n = 25,718 from 89 countries) tested hypotheses concerning generalizable positive and negative outcomes of social distancing messages that promoted personal agency and reflective choices (i.e., an autonomy-supportive message) or were restrictive and shaming (i.e., a controlling message) compared with no message at all. Results partially supported experimental hypotheses in that the controlling message increased controlled motivation (a poorly internalized form of motivation relying on shame, guilt, and fear of social consequences) relative to no message. On the other hand, the autonomy-supportive message lowered feelings of defiance compared with the controlling message, but the controlling message did not differ from receiving no message at all. Unexpectedly, messages did not influence autonomous motivation (a highly internalized form of motivation relying on one’s core values) or behavioral intentions. Results supported hypothesized associations between people’s existing autonomous and controlled motivations and self-reported behavioral intentions to engage in social distancing. Controlled motivation was associated with more defiance and less long-term behavioral intention to engage in social distancing, whereas autonomous motivation was associated with less defiance and more short- and long-term intentions to social distance. Overall, this work highlights the potential harm of using shaming and pressuring language in public health communication, with implications for the current and future global health challenges
