Short-Term Long Chain Omega3 Diet Protects from Neuroinflammatory Processes and Memory Impairment in Aged Mice

Regular consumption of food enriched in omega3 polyunsaturated fatty acids (ω3 PUFAs) has been shown to reduce risk of cognitive decline in elderly, and possibly development of Alzheimer's disease. Docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) are the most likely active components of ω3-rich PUFAs diets in the brain. We therefore hypothesized that exposing mice to a DHA and EPA enriched diet may reduce neuroinflammation and protect against memory impairment in aged mice. For this purpose, mice were exposed to a control diet throughout life and were further submitted to a diet enriched in EPA and DHA during 2 additional months. Cytokine expression together with a thorough analysis of astrocytes morphology assessed by a 3D reconstruction was measured in the hippocampus of young (3-month-old) and aged (22-month-old) mice. In addition, the effects of EPA and DHA on spatial memory and associated Fos activation in the hippocampus were assessed. We showed that a 2-month EPA/DHA treatment increased these long-chain ω3 PUFAs in the brain, prevented cytokines expression and astrocytes morphology changes in the hippocampus and restored spatial memory deficits and Fos-associated activation in the hippocampus of aged mice. Collectively, these data indicated that diet-induced accumulation of EPA and DHA in the brain protects against neuroinflammation and cognitive impairment linked to aging, further reinforcing the idea that increased EPA and DHA intake may provide protection to the brain of aged subjects

Impaired Interleukin-1β and c-Fos Expression in the Hippocampus Is Associated with a Spatial Memory Deficit in P2X7 Receptor-Deficient Mice

Recent evidence suggests that interleukin-1β (IL-1β), which was originally identified as a proinflammatory cytokine, is also required in the brain for memory processes. We have previously shown that IL-1β synthesis in the hippocampus is dependent on P2X7 receptor (P2X7R), which is an ionotropic receptor of ATP. To substantiate the role of P2X7R in both brain IL-1β expression and memory processes, we examined the induction of IL-1β mRNA expression in the hippocampus of wild-type (WT) and homozygous P2X7 receptor knockout mice (P2X7R−/−) following a spatial memory task. The spatial recognition task induced both IL-1β mRNA expression and c-Fos protein activation in the hippocampus of WT but not of P2X7R−/− mice. Remarkably, P2X7R−/− mice displayed spatial memory impairment in a hippocampal-dependant task, while their performances in an object recognition task were unaltered. Taken together, our results show that P2X7R plays a critical role in spatial memory processes and the associated hippocampal IL-1β mRNA synthesis and c-Fos activation

Uneven development and the commercialisation of public utilities: a political ecology analysis of water reforms in Malaysia

Water policy reforms introduced in Peninsular Malaysia have yielded relatively positive improvements in the operational and financial performance of water utilities. This article analyses contemporary water governance in the context of the historical origins of uneven water development in Malaysia and national heterogeneity in the political economy of water provision. The investigation builds on political ecology scholarship in urban water policy and reaffirms postcolonial critiques of neoliberal inspired water reforms in developing countries. Our study analyses the impact of the ‘asset light policy’ – a policy introduced in 2008 with the aim of commercialising public water utilities and centralising water sector investment and ownership. It is found that notwithstanding evidence of improved financial health and technical efficiency in certain states, the asset light policy has accentuated uneven water development across the country. Thus despite the policy’s relatively narrow focus on technical and financial matters, it is shown to have a fundamentally political outcome. This in turn explains the current ‘policy impasse’ in five of the eleven states in Peninsular Malaysia. Furthermore, the omission of environmental considerations within the policy framework is argued to undermine the overall ambition of the policy. It is recommended that water policy makers give greater consideration to the embedded social, political and economic inequalities that characterize many former European colonies

Alternative Splicing at a NAGNAG Acceptor Site as a Novel Phenotype Modifier

Approximately 30% of alleles causing genetic disorders generate premature termination codons (PTCs), which are usually associated with severe phenotypes. However, bypassing the deleterious stop codon can lead to a mild disease outcome. Splicing at NAGNAG tandem splice sites has been reported to result in insertion or deletion (indel) of three nucleotides. We identified such a mechanism as the origin of the mild to asymptomatic phenotype observed in cystic fibrosis patients homozygous for the E831X mutation (2623G>T) in the CFTR gene. Analyses performed on nasal epithelial cell mRNA detected three distinct isoforms, a considerably more complex situation than expected for a single nucleotide substitution. Structure-function studies and in silico analyses provided the first experimental evidence of an indel of a stop codon by alternative splicing at a NAGNAG acceptor site. In addition to contributing to proteome plasticity, alternative splicing at a NAGNAG tandem site can thus remove a disease-causing UAG stop codon. This molecular study reveals a naturally occurring mechanism where the effect of either modifier genes or epigenetic factors could be suspected. This finding is of importance for genetic counseling as well as for deciding appropriate therapeutic strategies

Shifting the Paradigm: The Putative Mitochondrial Protein ABCB6 Resides in the Lysosomes of Cells and in the Plasma Membrane of Erythrocytes

ABCB6, a member of the adenosine triphosphate–binding cassette (ABC) transporter family, has been proposed to be responsible for the mitochondrial uptake of porphyrins. Here we show that ABCB6 is a glycoprotein present in the membrane of mature erythrocytes and in exosomes released from reticulocytes during the final steps of erythroid maturation. Consistent with its presence in exosomes, endogenous ABCB6 is localized to the endo/lysosomal compartment, and is absent from the mitochondria of cells. Knock-down studies demonstrate that ABCB6 function is not required for de novo heme biosynthesis in differentiating K562 cells, excluding this ABC transporter as a key regulator of porphyrin synthesis. We confirm the mitochondrial localization of ABCB7, ABCB8 and ABCB10, suggesting that only three ABC transporters should be classified as mitochondrial proteins. Taken together, our results challenge the current paradigm linking the expression and function of ABCB6 to mitochondria

Vers une ville plus "convivialiste" : la voie de l'habitat participatif ?

International audienc

Salvador Juan, Anne Largo-Poirier, Hélène Orain, Jean-François Poltorak, Les sentiers du quotidien : rigidité, fluidité des espaces sociaux et trajets routiniers en ville, 1997

Costes Laurence. Salvador Juan, Anne Largo-Poirier, Hélène Orain, Jean-François Poltorak, Les sentiers du quotidien : rigidité, fluidité des espaces sociaux et trajets routiniers en ville, 1997. In: Les Annales de la recherche urbaine, N°79, 1998. Sports en ville. pp. 146-147

Neoliberalization and Evolution of the " Right to the City "

International audienceFor over two decades, various urban social movements have been growing in a number of cities around the world. Denouncing the effects of the neoliberal hold on the city, they aim to combat exclusion and to rethink the city. In the face of the growing urban inequalities, some have federated around the demand to a “right to the city”. By tracing the history of the international spread of the idea of the right to the city, this article intends to show how its applications have been more or less reworked according to local context. It emphasizes that the related narratives and concepts are endlessly readjusted to the worsening of the urban context by integrating very diverse ambitions to the point of deviating from the initial content, aiming for a profound transformation of society, towards an ethic of the city. But this strong resurgence of the “right to the city” also conveys an awareness of the acceleration and generalization of the injustices in the city resulting from neoliberalism. The components are based on the findings of research carried out around the work of Henri Lefebvre and an analysis of documents derived from national and international reports

Les petits commerçants du métro parisien

Die Händler der pariser « Métro ». Laurence COSTES Lange Zeit war das öffentliche Pariser Verkehrssystem (RATP) nur ein Ort des Verkehrs und des Transports, ein Raum, der ausschliesslich seiner ihm eigenen Funktion diente. Eine erst vor kurzem einsetzende Entwicklung bereitete diesem Zustand ein schnelles Ende. Heute öffnet sich die RATP zahlreichem Aktivitäten, die ehemals der Stadt vorenthalten waren. In zunehmendem Masse taucht der Handel in der RATP auf. Der Kommerz, zunächst im Bereich der RATP legal eingeführt, entwickelt sich nun schnell, auf unkontrollierte Art und Weise, und zieht dadurch eine besondere Art von Bevölkerung nach sich, die sich bervorzugt in diesem Bereich Platz verschafft. Die Urheber dieses Wandels sind vor allem Kaufleute, unterschiedlicher Herkunft, in den Arbeitsmethoden sich unterscheidend, offiziell vom Unternehmen RATP anerkannt oder am Rande der Legalität handelnd. Auch die Organisation dieser Kaufleute in den Offentlichen Räumen der RATP ist ein Feld einer eigenen Studie, die sich an folgenden zwei prinzipiellen Achsen orientieren kann : die eine bezieht sich auf die Beschäftigungsarten, die andere auf den ethnischen Aspekt der wirtschaftlichen Tätigkeit. In diesem Artikel wird man das Augenmerk zunächst auf die regulären Händler werfen, die durch ihre « Mini-boutique » offiziell auf einen vorgebenen Ort festgelegt sind. Sie unterhalten eingespielte Beziehungen mit der RATP. Es sind dies die Händler asiatischer Herkunft, spezialisiert auf einen bestimmten Typ eines Produkts, sie nehmen Verkaufs an, die ihren ganz eigenen sozialen, kulturellen und wirtschaftlichen Charakter widerspiegeln ; ebenso trifft man Inder, Afrikaner, Agypter un Maghrebaner an, mit ihren speziellen wirtschaftlichen Praktiken. Man wird auch noch die Situation der Verkäufer mit kleinen Ständen und Bauchläden untersuchen müssen, die illegal arbeiten. Letzere setzen sich ebenso aus verschiedenen Schichten zusammen ; sie haben es verstanden, ein besonderes Verkaufssystem, der Umgebung der Untergrundbahn angepasst, zu entwickeln. Sie haben sich Betätigungsfelder geschaffen, alle fein säuberlich voneinander getrennt...Small Retail Trade in the Paris « Métro » Laurence COSTES For a long time, the Régie Autonome des Transports Parisiens was nothing but a purely functional traffic area. That changea a lot recently, as RATP is extending the scope of its activities. Small trade was first introduced by law and is now developing without any control. Thus, new types of people have made that area their favourite field ofactivity. Their origin is diverse, and their methods of work are different. Thus the organization of these small shopkeepers in the RATP area makes it an interesting field of study in two ways : on the one hand, the type of activity, on the other, the ethnical aspects of that small trade. This paper considers first the regular shopkeepers, working on their assigned premises, called « mini-boutiques ». Their relationship to RATP has been formalized, they are of Eastern origin and specialize in given types of products. Their strategies depend upon their own social, cultural and economic resources. There are also Indians, Africans, Egyptians and North Africans, each group having its own trading habits. A number of illicit street hawkers are also to befound, they belong to various ethnic groups, who succeeded in creating a specific selling system, well-adapted to the Underground area. The boundaries of their « territory » have been strictly marked out.Les petits commerçants du métro parisien. Laurence COSTES Longtemps la Régie Autonome des Transports Parisiens (RATP) ne fut qu'un lieu de circulation, un espace à vocation purement fonctionnelle. Une évolution récente mit rapidement fin à cet état de chose. Aujourd'hui la RATP s'ouvre à de nouveaux services. L'activité commerciale, introduite tout d'abord légalement, se développe à présent rapidement, de façon incontrôlée, et entraîne avec elle une population particulière qui fait de ce domaine son lieu privilégié d'intervention. Les auteurs de cette transformation sont essentiellement des commerçants d'origines variées, aux méthodes de travail diversifiées. L'organisation de ces commerçants dans l'enceinte du métro est étudiée selon deux axes : l'un a trait aux modes d'occupation, l'autre à l'aspect ethnique de l'activité commerciale. Dans cet article, l'auteur s'intéresse, tout d'abord, aux commerçants réguliers : ils entretiennent des relations normalisées avec la RATP. Beaucoup sont des commerçants d'origine asiatique, spécialisés dans un certain type de produit ; ils adoptent des stratégies liées aux ressources sociales, culturelles, économiques qui leur sont propres. Des commerçants réguliers Indiens, Africains, Egyptiens, Maghrébins ont aussi des pratiques commerciales spécifiques. Quant aux vendeurs à la sauvette, ils appartiennent aussi à diverses ethnies qui ont su développer un système de vente particulier, adapté au milieu du métro. Leurs espaces de vente sont nettement délimités.Costes Laurence. Les petits commerçants du métro parisien. In: Revue européenne des migrations internationales, vol. 4, n°3,1988. pp. 57-71