553 research outputs found
Modulation of Multiple Sclerosis and its Animal Model experimental Autoimmune encephalomyelitis by Food and Gut Microbiota
Multiple sclerosis (MS) is an autoimmune neurological disease characterized by chronic inflammation of the central nervous system (CNS), leading to demyelination, axonal damage, and symptoms such as fatigue and disability. Although the cause of MS is not known, the infiltration of peripherally activated immune cells into the CNS has a key pathogenic role. Accumulating evidence supports an important role of diet and gut microbiota in immune-mediated diseases. Preclinical as well as clinical studies suggest a role for gut microbiota and dietary components in MS. Here, we review these recent studies on gut microbiota and dietary interventions in MS and its animal model experimental autoimmune encephalomyelitis. We also propose directions for future research
Multiple sclerosis is linked to MAPK(ERK) overactivity in microglia
Reassessment of published observations in patients with multiple sclerosis (MS) suggests a microglial malfunction due to inappropriate (over)activity of the mitogen-activated protein kinase pathway ERK (MAPKERK). These observations regard biochemistry as well as epigenetics, and all indicate involvement of this pathway. Recent preclinical research on neurodegeneration already pointed towards a role of MAPK pathways, in particular MAPKERK. This is important as microglia with overactive MAPK have been identified to disturb local oligodendrocytes which can lead to locoregional demyelination, hallmark of MS. This constitutes a new concept on pathophysiology of MS, besides the prevailing view, i.e., autoimmunity. Acknowledged risk factors for MS, such as EBV infection, hypovitaminosis D, and smoking, all downregulate MAPKERK negative feedback phosphatases that normally regulate MAPKERK activity. Consequently, these factors may contribute to inappropriate MAPKERK overactivity, and thereby to neurodegeneration. Also, MAPKERK overactivity in microglia, as a factor in the pathophysiology of MS, could explain ongoing neurodegeneration in MS patients despite optimized immunosuppressive or immunomodulatory treatment. Currently, for these patients with progressive disease, no effective treatment exists. In such refractory MS, targeting the cause of overactive MAPKERK in microglia merits further investigation as this phenomenon may imply a novel treatment approach
THE MANTECA YELLOW BEAN: A GENETIC RESOURCE OF FAST COOKING AND HIGH IRON BIOAVAILABILITY PHENOTYPES FOR THE NEXT GENERATION OF DRY BEANS (\u3ci\u3ePhaseolus vulgaris\u3c/i\u3e L.)
Dry beans (Phaseolus vulgaris L.) are a nutrient dense food produced globally as a major pulse crop for direct human consumption. Despite being rich in protein and micronutrients, long cooking times limit the use of dry beans worldwide, especially in regions relying on wood and charcoal as the primary sources of fuel for cooking, such as Sub-Sahara Africa and the Caribbean. Coincidently, these same regions also have high densities of women and children at risk for micronutrient deficiencies [1]. There is need for a fast cooking bean, which can positively impact consumers by reducing fuel cost and preparation time, while simultaneously complementing the nutritional quality of house-hold based meals [2].
To help accelerate a reliable increase in dry bean production for Sub-Saharan Africa, the Andean Bean Diversity Panel (ADP; http://arsftfbean.uprm.edu/bean/) was assembled as a genetic resource in the development of fast cooking, nutritional improved, biotic/abiotic resistant varieties. A germplasm screening for atmospheric cooking time (100oC) of over 200 bean accessions from the ADP identified only five fast cooking entries [3]. Two entries were white beans from Burundi (Blanco Fanesquero) and Ecuador (PI527521). Native to Chile, two of the six fast cooking entries were collected from Angola, and had a pale lemon ‘Manteca’ yellow seed color (Cebo, Mantega Blanca). Traditional knowledge from Chile suggests Manteca yellow beans are low flatulence and easy to digest [4].
Yellow beans of various shades are important in Eastern and Southern Africa. Their popularity has increased in recent years and they often fetch the highest prices at the marketplace. There is evidence to suggest that Manteca yellow beans have a unique nutritional profile when compared to other yellow seed types; with more soluble dietary fiber, less indigestible protein and starch, and are also free of condensed tannins. The hypothesis was tested that this unique composition would also have a positive influence on the bioavailability of iron in an in vitro digestion/Caco-2 cell culture bioassay
Does Dietary Mitigation of Enteric Methane Production Affect Rumen Function and Animal Productivity in Dairy Cows?
It has been suggested that the rumen microbiome and rumen function might be disrupted if methane production in the rumen is decreased. Furthermore concerns have been voiced that geography and management might influence the underlying microbial population and hence the response of the rumen to mitigation strategies. Here we report the effect of the dietary additives: linseed oil and nitrate on methane emissions, rumen fermentation, and the rumen microbiome in two experiments from New Zealand (Dairy 1) and the UK (Dairy 2). Dairy 1 was a randomized block design with 18 multiparous lactating cows. Dairy 2 was a complete replicated 3 x 3 Latin Square using 6 rumen cannulated, lactating dairy cows. Treatments consisted of a control total mixed ration (TMR), supplementation with linseed oil (4% of feed DM) and supplementation with nitrate (2% of feed DM) in both experiments. Methane emissions were measured in open circuit respiration chambers and rumen samples were analyzed for rumen fermentation parameters and microbial population structure using qPCR and next generation sequencing (NGS). Supplementation with nitrate, but not linseed oil, decreased methane yield (g/kg DMI; P<0.02) and increased hydrogen (P<0.03) emissions in both experiments. Furthermore, the effect of nitrate on gaseous emissions was accompanied by an increased rumen acetate to propionate ratio and consistent changes in the rumen microbial populations including a decreased abundance of the main genus Prevotella and a decrease in archaeal mcrA (log10 copies/g rumen DM content). These results demonstrate that methane emissions can be significantly decreased with nitrate supplementation with only minor, but consistent, effects on the rumen microbial population and its function, with no evidence that the response to dietary additives differed due to geography and different underlying microbial populations
Nutritional and ecological perspectives of the interrelationships between diet and the gut microbiome in multiple sclerosis:Insights from marmosets
Studies in experimental autoimmune encephalomyelitis (EAE), the animal model of multiple sclerosis, have shown potential links between diet components, microbiome composition, and modulation of immune responses. In this review, we reanalyze and discuss findings in an outbred marmoset EAE model in which a yogurt-based dietary supplement decreased disease frequency and severity. We show that although diet has detectable effects on the fecal microbiome, microbiome changes are more strongly associated with the EAE development. Using an ecological framework, we further show that the dominant factors influencing the gut microbiota were marmoset sibling pair and experimental time point. These findings emphasize challenges in assigning cause-and-effect relationships in studies of diet-microbiome-host interactions and differentiating the diet effects from other environmental, stochastic, and host-related factors. We advocate for animal experiments to be designed to allow causal inferences of the microbiota's role in pathology while considering the complex ecological processes that shape microbial communities
MAP3K4 Controls the Chromatin Modifier HDAC6 during Trophoblast Stem Cell Epithelial-to-Mesenchymal Transition
The first epithelial-to-mesenchymal transition (EMT) occurs in trophoblast stem (TS) cells during implantation. Inactivation of the serine/threonine kinase MAP3K4 in TS cells (TSKI4 cells) induces an intermediate state of EMT, where cells retain stemness, lose epithelial markers, and gain mesenchymal characteristics. Investigation of relationships among MAP3K4 activity, stemness, and EMT in TS cells may reveal key regulators of EMT. Here, we show that MAP3K4 activity controls EMT through the ubiquitination and degradation of HDAC6. Loss of MAP3K4 activity in TSKI4 cells results in elevated HDAC6 expression and the deacetylation of cytoplasmic and nuclear targets. In the nucleus, HDAC6 deacetylates the promoters of tight junction genes, promoting the dissolution of tight junctions. Importantly, HDAC6 knockdown in TSKI4 cells restores epithelial features, including cell-cell adhesion and barrier formation. These data define a role for HDAC6 in regulating gene expression during transitions between epithelial and mesenchymal phenotypes
Lymphocryptovirus infection of nonhuman primate b cells converts destructive into productive processing of the pathogenic CD8 T Cell epitope in myelin oligodendrocyte glycoprotein
Copyright © 2016 by The American Association of Immunologists, Inc. EBVis the major infectious environmental risk factor for multiple sclerosis (MS), but the underlying mechanisms remain obscure. Patient studies do not allow manipulation in vivo. We used the experimental autoimmune encephalomyelitis (EAE) models in the common marmoset and rhesus monkey to model the association of EBVand MS.We report that B cells infected with EBV-related lymphocryptovirus (LCV) are requisite APCs for MHC-E-restricted autoaggressive effector memory CTLs specific for the immunodominant epitope 40-48 of myelin oligodendrocyte glycoprotein (MOG). These T cells drive the EAE pathogenesis to irreversible neurologic deficit. The aim of this study was to determine why LCV infection is important for this pathogenic role of B cells. Transcriptome comparison of LCV-infected B cells and CD20+ spleen cells from rhesus monkeys shows increased expression of genes encoding elements of the Ag cross-presentation machinery (i.e., of proteasome maturation protein and immunoproteasome subunits) and enhanced expression of MHC-E and of costimulatory molecules (CD70 and CD80, but not CD86). It was also shown that altered expression of endolysosomal proteases (cathepsins) mitigates the fast endolysosomal degradation of the MOG40-48 core epitope. Finally, LCV infection also induced expression of LC3-II+ cytosolic structures resembling autophagosomes, which seem to form an intracellular compartment where theMOG40-48 epitope is protected against proteolytic degradation by the endolysosomal serine protease cathepsin G. In conclusion, LCV infection induces a variety of changes in B cells that underlies the conversion of destructive processing of the immunodominant MOG40-48 epitope into productive processing and cross-presentation to strongly autoaggressive CTLs
- …