Search results for "Mine"
showing 10 items of 20410 documents
Structure-Activity Relationship Analysis of 3-Phenylcoumarin-Based Monoamine Oxidase B Inhibitors
2018
Monoamine oxidase B (MAO-B) catalyzes deamination of monoamines such as neurotransmitters dopamine and norepinephrine. Accordingly, small-molecule MAO-B inhibitors potentially alleviate the symptoms of dopamine-linked neuropathologies such as depression or Parkinson's disease. Coumarin with a functionalized 3-phenyl ring system is a promising scaffold for building potent MAO-B inhibitors. Here, a vast set of 3-phenylcoumarin derivatives was designed using virtual combinatorial chemistry or rationally de novo and synthesized using microwave chemistry. The derivatives inhibited the MAO-B at 100 nM−1 μM. The IC50 value of the most potent derivative 1 was 56 nM. A docking-based structure-activi…
Estrogen Regulates the Satellite Cell Compartment in Females
2019
SUMMARY Skeletal muscle mass, strength, and regenerative capacity decline with age, with many measures showing a greater deterioration in females around the time estrogen levels decrease at menopause. Here, we show that estrogen deficiency severely compromises the maintenance of muscle stem cells (i.e., satellite cells) as well as impairs self-renewal and differentiation into muscle fibers. Mechanistically, by hormone replacement, use of a selective estrogen-receptor modulator (bazedoxifene), and conditional estrogen receptor knockout, we implicate 17β-estradiol and satellite cell expression of estrogen receptor α and show that estrogen signaling through this receptor is necessary to preven…
Hydrogen Bond Fluctuations Control Photochromism in a Reversibly Photo-Switchable Fluorescent Protein
2015
Reversibly switchable fluorescent proteins (RSFPs) are essential for high-resolution microscopy of biological samples, but the reason why these proteins are photochromic is still poorly understood. To address this problem, we performed molecular dynamics simulations of the fast switching Met159Thr mutant of the RSFP Dronpa. Our simulations revealed a ground state structural heterogeneity in the chromophore pocket that consists of three populations with one, two, or three hydrogen bonds to the phenolate moiety of the chromophore. By means of non-adiabatic quantum mechanics/molecular dynamics simulations, we demonstrated that the subpopulation with a single hydrogen bond is responsible for of…
Dysregulation of C-X-C motif ligand 10 during aging and association with cognitive performance
2017
International audience; Chronic low-grade inflammation during aging (inflammaging) is associated with cognitive decline and neurodegeneration; however, the mechanisms underlying inflammaging are unclear. We studied a population (n = 361) of healthy young and old adults from the MyoAge cohort. Peripheral levels of C-X-C motif chemokine ligand 10 (CXCL10) was found to be higher in older adults, compared with young, and negatively associated with working memory performance. This coincided with an age-related reduction in blood DNA methylation at specific CpGs within the CXCL10 gene promoter. In vitro analysis supported the role of DNA methylation in regulating CXCL10 transcription. A polymorph…
Endocannabinoid LTD in Accumbal D1 Neurons Mediates Reward-Seeking Behavior
2020
Summary The nucleus accumbens (NAc) plays a key role in drug-related behavior and natural reward learning. Synaptic plasticity in dopamine D1 and D2 receptor medium spiny neurons (MSNs) of the NAc and the endogenous cannabinoid (eCB) system have been implicated in reward seeking. However, the precise molecular and physiological basis of reward-seeking behavior remains unknown. We found that the specific deletion of metabotropic glutamate receptor 5 (mGluR5) in D1-expressing MSNs (D1miRmGluR5 mice) abolishes eCB-mediated long-term depression (LTD) and prevents the expression of drug (cocaine and ethanol), natural reward (saccharin), and brain-stimulation-seeking behavior. In vivo enhancement…
Is there evidence for a rostral-caudal gradient in fronto-striatal loops and what role does dopamine play?
2018
Research has shown that the lateral prefrontal cortex (LPFC) may be hierarchically organized along a rostral-caudal functional gradient such that control processing becomes progressively more abstract from caudal to rostral frontal regions. Here, we briefly review the most recent functional MRI, neuropsychological, and electrophysiological evidence in support of a hierarchical LPFC organization. We extend these observations by discussing how such a rostral-caudal gradient may also exist in the striatum and how the dopaminergic system may play an important role in the hierarchical organization of fronto-striatal loops. There is evidence indicating that a rostral-caudal gradient of dopamine r…
Association of interleukin-6 rs1800796 polymorphism with reduced cognitive performance in healthy older adults
2019
© 2018 Elsevier B.V. With increasing life expectancy, age-associated cognitive impairment is an escalating problem worldwide. Inflammation is one of the features that characterises cognitive decline and can stimulate neurodegeneration. Interleukin 6 (IL-6) is a cytokine frequently associated with a pro-inflammatory phenotype and increased levels have been associated with the pathogenesis of dementia. The rs1800796 polymorphism in the promoter region of IL-6 gene was previously shown to influence IL-6 expression and therefore we hypothesised this gene polymorphism would be associated with IL-6 plasma levels and cognitive performance of older adults. The present study investigated the associa…
Vγ9Vδ2 T Cells in the Bone Marrow of Myeloma Patients: A Paradigm of Microenvironment-Induced Immune Suppression
2018
Vγ9Vδ2 T cells are non-conventional T cells with a natural inclination to recognize and kill cancer cells. Malignant B cells, including myeloma cells, are privileged targets of Vγ9Vδ2 T cells in vitro. However, this inclination is often lost in vivo due to multiple mechanisms mediated by tumor cells and local microenvironment. Multiple myeloma (MM) is a paradigm disease in which antitumor immunity is selectively impaired at the tumor site. By interrogating the immune reactivity of bone marrow (BM) Vγ9Vδ2 T cells to phosphoantigens, we have revealed a very early and long-lasting impairment of Vγ9Vδ2 T-cell immune functions which is already detectable in monoclonal gammopathy of undetermined …
The shell of the invasive bivalve species Dreissena polymorpha: biochemical, elemental and textural Investigations.
2016
28 pages; International audience; The zebra mussel Dreissena polymorpha is a well-established invasive model organism. Although extensively used in environmental sciences, virtually nothing is known of the molecular process of its shell calcification. By describing the microstructure, geochemistry and biochemistry/proteomics of the shell, the present study aims at promoting this species as a model organism in biomineralization studies, in order to establish a bridge with ecotoxicology, while sketching evolutionary conclusions. The shell of D. polymorpha exhibits the classical crossed-lamellar/complex crossed lamellar combination found in several heterodont bivalves, in addition to an extern…
Toxicity of biomining effluents to Daphnia magna: Acute toxicity and transcriptomic biomarkers
2018
Increasing metal consumption is driving the introduction of new techniques such as biomining to exploit low grade ores. The biomining impacts notably aquatic ecosystems, yet, the applicability of ecotoxicological tests to study the complex mixture effects of mining waters is insufficiently understood. The aim of the present work was to test if transcriptomic biomarkers are suitable and sensitive for the ecotoxicity assessment of biomining affected waters. The study site had been affected by a multimetal biomine, and the studied water samples formed a concentration gradient of contamination downstream from the biomining site. Cadmium and nickel were used as positive controls in the toxicity …