Search results for "Inhibition"
showing 10 items of 590 documents
Effects of social stress and clomipramine on emotional memory in mice.
2017
We have previously observed impairing effects of social defeat stress (CSDS) on inhibitory avoidance (IA) in mice. Given the similarity between changes produced by social stress in animals and symptoms of certain human psychopathologies such as depression and anxiety, the effects of the antidepressant clomipramine on IA impairment produced by CSDS were evaluated in the present study. Male CD1 mice were randomly assigned to the groups: non-stressed+saline, non-stressed+clomipramine, stressed+saline and stressed+clomipramine. Stressed animals were subjected to daily agonistic encounters (10 min) in the home cage of the aggressor over a 20-day period. Just before each encounter, non-stressed a…
Interhemispheric inhibition is dynamically regulated during action observation
2016
International audience; It is now well established that the motor system plays a pivotal role in action observation and that the neurophysiological processes underlying perception and action overlaps. However, while various experiments have shown a specific facilitation of the contralateral motor cortex during action observation, no information is available concerning the dynamics of interhemispheric interactions. The aim of the present study was, therefore, to assess interhemispheric inhibition during the observation of others' actions. We designed a transcranial magnetic stimulation (TMS) experiment in which we measured both corticospinal excitability and interhemispheric inhibition, this…
Spinal plasticity with motor imagery practice.
2019
KEY POINTS: While a consensus has now been reached on the effect of motor imagery (MI) – the mental simulation of an action – on motor cortical areas, less is known about its impact on spinal structures. The current study, using H‐reflex conditioning paradigms, examined the effect of a 20 min MI practice on several spinal mechanisms of the plantar flexor muscles. We observed modulations of spinal presynaptic circuitry while imagining, which was even more pronounced following an acute session of MI practice. We suggested that the small cortical output generated during MI may reach specific spinal circuits and that repeating MI may increase the sensitivity of the spinal cord to its effects. T…
A 13 mer LNA-i-miR-221 Inhibitor Restores Drug Sensitivity in Melphalan-Refractory Multiple Myeloma Cells.
2016
Abstract Purpose: The onset of drug resistance is a major cause of treatment failure in multiple myeloma. Although increasing evidence is defining the role of miRNAs in mediating drug resistance, their potential activity as drug-sensitizing agents has not yet been investigated in multiple myeloma. Experimental Design: Here we studied the potential utility of miR-221/222 inhibition in sensitizing refractory multiple myeloma cells to melphalan. Results: miR-221/222 expression inversely correlated with melphalan sensitivity of multiple myeloma cells. Inhibition of miR-221/222 overcame melphalan resistance and triggered apoptosis of multiple myeloma cells in vitro, in the presence or absence of…
Metabolic complementation in bacterial communities: Necessary conditions and optimality
2016
Bacterial communities may display metabolic complementation, in which different members of the association partially contribute to the same biosynthetic pathway. In this way, the end product of the pathway is synthesized by the community as a whole. However, the emergence and the benefits of such complementation are poorly understood. Herein, we present a simple model to analyze the metabolic interactions among bacteria, including the host in the case of endosymbiotic bacteria. The model considers two cell populations, with both cell types encoding for the same linear biosynthetic pathway. We have found that, for metabolic complementation to emerge as an optimal strategy, both product inhib…
Selection of New Probiotics for Endometrial Health
2019
Microbiota is a crucial player in gynecologic health, in which bacteria can shift to a dysbiotic state triggering a pathogenic process. Based on an ecological understanding of the problem, the aim of this study is to select a potential probiotic strain to improve female reproductive tract based on its capacity to initially lower pH and to promote the reduction of pathogenic bacteria. Based on this rationale, strain Lactobacillus rhamnosus BPL005 was initially selected for its capacity to reduce in vitro pH levels and produce organic acids. Subsequently, strain L. rhamnosus BPL005 (CECT 8800) was demonstrated to have a protective role on endometrial infections in an in vitro model of bacteri…
Ribosome-Targeting Antibiotics Impair T Cell Effector Function and Ameliorate Autoimmunity by Blocking Mitochondrial Protein Synthesis
2019
Summary While antibiotics are intended to specifically target bacteria, most are known to affect host cell physiology. In addition, some antibiotic classes are reported as immunosuppressive for reasons that remain unclear. Here, we show that Linezolid, a ribosomal-targeting antibiotic (RAbo), effectively blocked the course of a T cell-mediated autoimmune disease. Linezolid and other RAbos were strong inhibitors of T helper-17 cell effector function in vitro, showing that this effect was independent of their antibiotic activity. Perturbing mitochondrial translation in differentiating T cells, either with RAbos or through the inhibition of mitochondrial elongation factor G1 (mEF-G1) progressi…
The dimer-monomer equilibrium of SARS-CoV-2 main protease is affected by small molecule inhibitors
2021
AbstractThe maturation of coronavirus SARS-CoV-2, which is the etiological agent at the origin of the COVID-19 pandemic, requires a main protease Mpro to cleave the virus-encoded polyproteins. Despite a wealth of experimental information already available, there is wide disagreement about the Mpro monomer-dimer equilibrium dissociation constant. Since the functional unit of Mpro is a homodimer, the detailed knowledge of the thermodynamics of this equilibrium is a key piece of information for possible therapeutic intervention, with small molecules interfering with dimerization being potential broad-spectrum antiviral drug leads. In the present study, we exploit Small Angle X-ray Scattering (…
Inhibition of human monoamine oxidase A and B by flavonoids isolated from two Algerian medicinal plants
2017
Abstract Background Monoamine oxidases (MAOs) are outer mitochondrial membrane flavoenzymes. They catalyze the oxidative deamination of a variety of neurotransmitters. MAO-A and MAO-B may be considered as targets for inhibitors to treat neurodegenerative diseases and depression and for managing symptoms associated with Parkinson's and Alzheimer's diseases. Purpose The objective was to evaluate the inhibitory effect of Hypericum afrum and Cytisus villosus against MAO-A and B and to isolate the compounds responsible for the MAO-inhibitory activity. Methods The inhibitory effect of extracts and purified constituents of H. afrum and C. villosus were investigated in vitro using recombinant human…
Auxiliary α2δ1 and α2δ3 Subunits of Calcium Channels Drive Excitatory and Inhibitory Neuronal Network Development
2020
VGCCs are multisubunit complexes that play a crucial role in neuronal signaling. Auxiliary α2δ subunits of VGCCs modulate trafficking and biophysical properties of the pore-forming α1 subunit and trigger excitatory synaptogenesis. Alterations in the expression level of α2δ subunits were implicated in several syndromes and diseases, including chronic neuropathic pain, autism, and epilepsy. However, the contribution of distinct α2δ subunits to excitatory/inhibitory imbalance and aberrant network connectivity characteristic for these pathologic conditions remains unclear. Here, we show that α2δ1 overexpression enhances spontaneous neuronal network activity in developing and mature cultures of …