Search results for " MICE"
showing 10 items of 558 documents
Inflammation and the coagulation system in tuberculosis: Tissue Factor leads the dance
2016
Mycobacterium tuberculosis, the causative agent of tuberculosis, drives the formation of granulomas, structures in which both immune cells and the bacterial pathogen cohabit. The most abundant cells in granulomas are macrophages, which contribute as both cells with bactericidal activity and as targets for M. tuberculosis infection and proliferation during the entire course of infection. The mechanisms and factors involved in the regulation and control of macrophage microenvironment-specific polarization and plasticity are not well understood, as some granulomas are able to control bacteria growth and others fail to do so, permitting bacterial spread. In this issue of the European Journal of…
Effects of muscular dystrophy, exercise and blocking activin receptor IIB ligands on the unfolded protein response and oxidative stress
2016
Protein homeostasis in cells, proteostasis, is maintained through several integrated processes and pathways and its dysregulation may mediate pathology in many diseases including Duchenne muscular dystrophy (DMD). Oxidative stress, heat shock proteins, endoplasmic reticulum (ER) stress and its response, i.e. unfolded protein response (UPR), play key roles in proteostasis but their involvement in the pathology of DMD are largely unknown. Moreover, exercise and activin receptor IIB blocking are two strategies that may be beneficial to DMD muscle, but studies to examine their effects on these proteostasis pathways are lacking. Therefore, these pathways were examined in the muscle of mdx mice, …
Impaired Kupffer Cell Self-Renewal Alters the Liver Response to Lipid Overload during Non-alcoholic Steatohepatitis
2020
International audience; Kupffer cells (KCs) are liver-resident macrophages that self-renew by proliferation in the adult independently from monocytes. However, how they are maintained during non-alcoholic steatohepatitis (NASH) remains ill defined. We found that a fraction of KCs derived from Ly-6C+ monocytes during NASH, underlying impaired KC self-renewal. Monocyte-derived KCs (MoKCs) gradually seeded the KC pool as disease progressed in a response to embryo-derived KC (EmKC) death. Those MoKCs were partly immature and exhibited a pro-inflammatory status compared to EmKCs. Yet, they engrafted the KC pool for the long term as they remained following disease regression while acquiring matur…
Hypocellularity in the murine model for Down Syndrome Ts65Dn is not affected by adult neurogenesis
2016
Down syndrome (DS) is caused by the presence of an extra copy of the chromosome 21 and it is the most common aneuploidy producing intellectual disability. Neural mechanisms underlying this alteration may include defects in the formation of neuronal networks, information processing and brain plasticity. The murine model for DS, Ts65Dn, presents reduced adult neurogenesis. This reduction has been suggested to underlie the hypocellularity of the hippocampus as well as the deficit in olfactory learning in the Ts65Dn mice. Similar alterations have also been observed in individuals with DS. To determine whether the impairment in adult neurogenesis is, in fact, responsible for the hypocellularity …
Enhancement of Wound Healing in Normal and Diabetic Mice by Topical Application of Amorphous Polyphosphate. Superior Effect of a Host⁻Guest Composite…
2017
The effect of polyphosphate (polyP) microparticles on wound healing was tested both in vitro and in a mice model in vivo. Two approaches were used: pure salts of polyphosphate, fabricated as amorphous microparticles (MPs, consisting of calcium and magnesium salts of polyP, “Ca–polyp-MPs” and “Mg–polyp-MPs”), and host–guest composite particles, prepared from amorphous collagen (host) and polyphosphate (guest), termed “col/polyp-MPs”. Animal experiments with polyP on healing of excisional wounds were performed using both normal mice and diabetic mice. After a healing period of 7 days “Ca–polyp-MP” significantly improved re-epithelialization in normal mice from 31% (control) to 72% (polyP micr…
TLR2 modulates gut colonization and dissemination of Candida albicans in a murine model
2016
Invasive candidiasis often arises from translocation of endogenous yeasts from the gastrointestinal tract to the bloodstream. Here we describe that both wild type and TLR2−/− mice strains, orally administered with Candida albicans yeasts, display similar sustained high level of gut colonization when oral antibacterial treatment is present, while removal of antibiotic treatment causes a progressive clearance of yeasts in control but not in TLR2−/− mice. Fungal invasion of internal organs, following immunosuppression of colonized mice, was increased in TLR2−/− mice. These results point out to a role of TLR2 in gut protection against colonization and endogenous invasion by C. albicans. This wo…
Introducing Clicker Training as a Cognitive Enrichment for Laboratory Mice
2017
Establishing new refinement strategies in laboratory animal science is a central goal in fulfilling the requirements of Directive 2010/63/EU. Previous research determined a profound impact of gentle handling protocols on the well-being of laboratory mice. By introducing clicker training to the keeping of mice, not only do we promote the amicable treatment of mice, but we also enable them to experience cognitive enrichment. Clicker training is a form of positive reinforcement training using a conditioned secondary reinforcer, the "click" sound of a clicker, which serves as a time bridge between the strengthened behavior and an upcoming reward. The effective implementation of the clicker trai…
Intestinal microbiota mediates the beneficial effects of n-3 polyunsaturated fatty acids during dietary obesity,
2021
Obesity, now considered as a real worldwide epidemic affecting more than 650 million people, is complex and mainly associated with excessive energy intake and changes in eating habits favoring the consumption of diets rich in saturated fat and sugar. This multifactorial pathology is linked to chronic low grade systemic inflammation. Indeed, a high fat diet (HFD) leads to intestinal microbiota dysbiosis increasing gut permeability (partly attributed to a downregulation of genes encoding tight junction proteins) leading to an increase in bacterial lipopolysaccharides (LPS) levels so-called metabolic endotoxemia. Studies have shown that n-3 polyunsaturated fatty acids (PUFAs) are involved in t…
Srebf2 Locus Overexpression Reduces Body Weight, Total Cholesterol and Glucose Levels in Mice Fed with Two Different Diets
2020
Macronutrients represent risk factors for hyperlipidemia or diabetes. Lipid alterations and type 2 diabetes mellitus are global health problems. Overexpression of sterol regulatory element-binding factor (Srebf2) in transgenic animals is linked to elevated cholesterol levels and diabetes development. We investigated the impact of increased Srebf2 locus expression and the effects of control and high-fat, high-sucrose (HFHS) diets on body weight, glucose and lipid metabolisms in transgenic mice (S-mice). Wild type (WT) and S-mice were fed with both diets for 16 weeks. Plasma glucose, insulin and lipids were assessed (n = 25). Immunostainings were performed in liver, pancreas and fat (N = 10).…
Therapeutic Potential of AntagomiR-23b for Treating Myotonic Dystrophy
2020
Myotonic dystrophy type 1 (DM1) is a chronically debilitating, rare genetic disease that originates from an expansion of a noncoding CTG repeat in the dystrophia myotonica protein kinase (DMPK) gene. The expansion becomes pathogenic when DMPK transcripts contain 50 or more repetitions due to the sequestration of the muscleblind-like (MBNL) family of proteins. Depletion of MBNLs causes alterations in splicing patterns in transcripts that contribute to clinical symptoms such as myotonia and muscle weakness and wasting. We previously found that microRNA (miR)-23b directly regulates MBNL1 in DM1 myoblasts and mice and that antisense technology (“antagomiRs”) blocking this microRNA (miRNA) boost…