Search results for "homeostasi"
showing 10 items of 636 documents
Fructose diet induced short-term impairment of cone sensitivity and gene expression in rat retina
2012
National audience; Abstract: Purpose A high fructose diet has been widely used to trigger insulin resistance in rodent; insulin resistance is one of the major risk factor for the development of type 2 diabetes. Thirty to 40% of diabetic patients develop diabetic retinopathy. In this study, we aimed to evaluate the short-term effect, at 1, 3, 5, 8 days, of a 60% fructose diet, on photoreceptor sensitivity and gene expression in the retina of Brown Norway rats. Methods: Flicker electroretinograms (8Hz) were recorded under anesthesia, from both eyes simultaneously in order to study sensitivity of photoreceptors. Then, rats were euthanized and enucleated. Retinae and posterior poles were collec…
The consumption of a bread enriched with dietary fibre and l-carnitine improves glucose homoeostasis and insulin sensitivity in patients with metabol…
2015
The aim of this study was to evaluate the efficacy of a bakery product enriched with dietary fibre and L-carnitine in countering glucose homoeostasis and insulin sensitivity in patients with and without MetS. This was a 12-week, double-blind, randomized placebo-controlled trial employing fifty-four subjects (28 with MetS and 26 without MetS). After one month (run-in period), subjects were divided into two intervention groups: one received dietary fibre (5.59 g of soluble fibre and 9.49 g of insoluble fibre) plus 2325 mg of L-carnitine enriched bread (n = 26) and the other received placebo bread (n = 28). Anthropometric measurements, biochemical parameters inflammatory markers and LDL subfra…
Constitutive androstane receptor activation stimulates faecal bile acid excretion and reverse cholesterol transport in mice.
2010
The constitutive androstane receptor (CAR) is a nuclear receptor expressed in the liver and involved in xenobiotic metabolism. The aim of this study was to assess whether pharmacological CAR activation could affect neutral sterol and bile acid elimination under conditions of cholesterol overload.Wild type, Car-/-, ApoE-/-, and low-density lipoprotein receptor (Ldlr)-/- mice fed a western-type diet were treated with the CAR agonist TCPOBOP.CAR activation was associated with a decrease in faecal cholesterol output related to the repression of the Abcg5/g8 cholesterol transporters. In contrast, TCPOBOP treatment induced a marked increase (up to three fold, p0.01) in the elimination of faecal b…
Hyperinsulinemia, hyperproinsulinemia and insulin resistance in the metabolic syndrome.
1996
For better comprehension of the metabolic syndrome, it is necessary to differentiate the effect of insulin on glucose metabolism on the one hand, and on other metabolic activities on the other hand. Whereas glucose utilization is affected by insulin resistance, the effect of insulin on lipid metabolism, ion and aminoacid transport does not seem to be diminished. Lipid metabolism, however, seems to play a crucial role in the induction of the vicious cycle. Increased energy and fat ingestion may be due to an increased number of galanin secreting cells in the hypothalamus. The excessive fat intake results in an increased rate of release of insulin and increased influx of triglycerides into the…
The histone acetyltransferase MOF activates hypothalamic polysialylation to prevent diet-induced obesity in mice
2014
Overfeeding causes rapid synaptic remodeling in hypothalamus feeding circuits. Polysialylation of cell surface molecules is a key step in this neuronal rewiring and allows normalization of food intake. Here we examined the role of hypothalamic polysialylation in the long-term maintenance of body weight, and deciphered the molecular sequence underlying its nutritional regulation. We found that upon high fat diet (HFD), reduced hypothalamic polysialylation exacerbated the diet-induced obese phenotype in mice. Upon HFD, the histone acetyltransferase MOF was rapidly recruited on the St8sia4 polysialyltransferase-encoding gene. Mof silencing in the mediobasal hypothalamus of adult mice prevented…
Immune-Inflammatory Responses and Oxidative Stress in Alzheimers Disease: Therapeutic Implications
2010
Alzheimer's disease (AD) is a heterogeneous and progressive neurodegenerative disease which in Western society mainly accounts for clinical dementia. AD has been linked to inflammation and oxidative stress. Neuro-pathological hallmarks are senile plaques, resulting from the accumulation of several proteins and an inflammatory reaction around deposits of amyloid, a fibrillar protein, Abeta, product of cleavage of a much larger protein, the beta-amyloid precursor protein (APP) and neurofibrillary tangles. Inflammation clearly occurs in pathologically vulnerable regions of AD and several inflammatory factors influencing AD development, i.e. environmental factors (pro-inflammatory phenotype) an…
Concept of an extracellular regulation of muscular metabolic rate during heavy exercise in humans by psychophysiological feedback.
1996
Efferent motor signals to skeletal muscles concern not only the space/ time pattern of motion, but also the setting of muscular performance and through this the control of the current metabolic rate. For an optimal adjustment of metabolic rate during heavy exercise-e.g. in athletic competitions-a feedback control system must exist, including a programmer that takes into consideration a finishing point (teleoanticipation). The presented experiments, using Borg's scale, indicate the existence and functioning of a system for optimal adjustment of performance during heavy exercise and the relevance of teleoanticipatory effects. Thus motor learning includes not only somatosensory control, but al…
Transcription factors controlling development and function of innate lymphoid cells.
2014
Abstract Innate lymphoid cells (ILCs) are a heterogeneous group of lymphocytes, which play an important role in tissue homeostasis at epithelial surfaces. They are scarce in spleen and lymph nodes, but substantial numbers can be found in the intestinal mucosa even at steady state. There, they represent the first line of defence against invading pathogens and contribute to lymphorganogenesis, tissue repair and, when inappropriately activated, immune pathology. Lineage-specific development, function and maintenance of these cells depend on a restricted set of transcription factors that partially emerged as a result of diversification and selection during vertebrate evolution. The differential…
Differential requirements for antigen or homeostatic cytokines for proliferation and differentiation of human Vgamma9Vdelta2 naive, memory and effect…
2005
We have compared four human subsets of Vgamma9Vdelta2 T cells, naive (T(naive), CD45RA(+)CD27(+)), central memory (T(CM), CD45RA(-)CD27(+)), effector memory (T(EM), CD45RA(-)CD27(-)) and terminally differentiated (T(EMRA), CD45RA(+)CD27(-)), for their capacity to proliferate and differentiate in response to antigen or homeostatic cytokines. Cytokine responsiveness and IL-15R expression were low in T(naive) cells and progressively increased from T(CM) to T(EM) and T(EMRA) cells. In contrast, the capacity to expand in response to antigen or cytokine stimulation showed a reciprocal pattern and was associated with resistance to cell death and Bcl-2 expression. Whereas antigen-stimulated cells a…
CD40 activity on mesenchymal cells negatively regulates OX40L to maintain bone marrow immune homeostasis under stress conditions
2021
BackgroundWithin the bone marrow (BM), mature T cells are maintained under homeostatic conditions to facilitate proper hematopoietic development. This homeostasis depends upon a peculiar elevated frequency of regulatory T cells (Tregs) and immune regulatory activities from BM-mesenchymal stem cells (BM-MSCs). In response to BM transplantation (BMT), the conditioning regimen exposes the BM to a dramatic induction of inflammatory cytokines and causes an unbalanced T-effector (Teff) and Treg ratio. This imbalance negatively impacts hematopoiesis, particularly in regard to B-cell lymphopoiesis that requires an intact cross-talk between BM-MSCs and Tregs. The mechanisms underlying the ability of…