Hsp27 (HspB1) and αB-crystallin (HspB5) as therapeutic targets

AbstractHsp27 and αB-crystallin are molecular chaperones that are constitutively expressed in several mammalian cells, particularly in pathological conditions. These proteins share functions as diverse as protection against toxicity mediated by aberrantly folded proteins or oxidative-inflammation conditions. In addition, these proteins share anti-apoptotic properties and are tumorigenic when expressed in cancer cells. This review summarizes the current knowledge about Hsp27 and αB-crystallin and the implications, either positive or deleterious, of these proteins in pathologies such as neurodegenerative diseases, myopathies, asthma, cataracts and cancers. Approaches towards therapeutic strategies aimed at modulating the expression and/or the activities of Hsp27 and αB-crystallin are presented

Knock Down of Heat Shock Protein 27 (HspB1) Induces Degradation of Several Putative Client Proteins

Hsp27 belongs to the heat shock protein family and displays chaperone properties in stress conditions by holding unfolded polypeptides, hence avoiding their inclination to aggregate. Hsp27 is often referenced as an anti-cancer therapeutic target, but apart from its well-described ability to interfere with different stresses and apoptotic processes, its role in non-stressed conditions is still not well defined. In the present study we report that three polypeptides (histone deacetylase HDAC6, transcription factor STAT2 and procaspase-3) were degraded in human cancerous cells displaying genetically decreased levels of Hsp27. In addition, these proteins interacted with Hsp27 complexes of different native size. Altogether, these findings suggest that HDAC6, STAT2 and procaspase-3 are client proteins of Hsp27. Hence, in non stressed cancerous cells, the structural organization of Hsp27 appears to be a key parameter in the regulation by this chaperone of the level of specific polypeptides through client-chaperone type of interactions

A História da Alimentação: balizas historiográficas

Os M. pretenderam traçar um quadro da História da Alimentação, não como um novo ramo epistemológico da disciplina, mas como um campo em desenvolvimento de práticas e atividades especializadas, incluindo pesquisa, formação, publicações, associações, encontros acadêmicos, etc. Um breve relato das condições em que tal campo se assentou faz-se preceder de um panorama dos estudos de alimentação e temas correia tos, em geral, segundo cinco abardagens Ia biológica, a econômica, a social, a cultural e a filosófica!, assim como da identificação das contribuições mais relevantes da Antropologia, Arqueologia, Sociologia e Geografia. A fim de comentar a multiforme e volumosa bibliografia histórica, foi ela organizada segundo critérios morfológicos. A seguir, alguns tópicos importantes mereceram tratamento à parte: a fome, o alimento e o domínio religioso, as descobertas européias e a difusão mundial de alimentos, gosto e gastronomia. O artigo se encerra com um rápido balanço crítico da historiografia brasileira sobre o tema

RECRUTEMENT DES URGENCES MEDICALES PEDIATRIQUES DE L'HOPITAL SAINT-VINCENT DE PAUL

PARIS-BIUM (751062103) / SudocCentre Technique Livre Ens. Sup. (774682301) / SudocSudocFranceF

GROSSESSE ET HEMODIALYSE (A PROPOS D'UN CAS ET REVUE DE LA LITTERATURE)

LYON1-BU Santé (693882101) / SudocPARIS-BIUM (751062103) / SudocSudocFranceF

The lysine-ketoglutarate reductase-saccharopine dehydrogenase is involved in the osmo-induced synthesis of pipecolic acid in rapeseed leaf tissus

International audienceHigher plant responses to abiotic stresses are associated with physiological and biochemical changes triggering a number of metabolic adjustments. We focused on l-lysine catabolism, and have previously demonstrated that degradation of this amino acid is osmo-regulated at the level of lysine-ketoglutarate reductase (LKR, EC 1.5.1.8) and saccharopine dehydrogenase (SDH, EC 1.5.1.9) in Brassica napus. LKR and SDH activities are enhanced by decreasing osmotic potential and decrease when the upshock osmotic treatment is followed by a downshock osmotic one. Moreover we have shown that the B. napus LKR/SDH gene is up-regulated in osmotically-stressed tissues. The LKR/SDH activity produces alpha-aminoadipate semialdehyde which could be further converted into alpha-aminoadipate and acetyl CoA. Alternatively alpha-aminoadipate could behave as a precursor for pipecolic acid. Pipecolic acid is described as an osmoprotectant in bacteria and is co-accumulated with proline in halophytic plants. We suggest that osmo-induction of the LKR/SDH activity could be partly responsible for pipecolic acid accumulation. This proposal has been assessed in this study through pipecolic acid amounts determination in rape leaf discs subjected to various upshift and downshift osmotic treatments. Changes in pipecolic acid level actually behave as those observed for LKR and SDH activities, since it increases or decreases in rape leaf discs treated under hyper- or hypo-osmotic conditions, respectively. In addition we show that pipecolic acid level is positively correlated with the external osmotic potential as well as with the duration of the applied treatment. On the other hand pipecolic acid level is related to the availability of l-lysine and not to that of d-lysine. Collectively the results obtained demonstrate that lysine catabolism through LKR/SDH activity is involved in osmo-induced synthesis of pipecolic aci

Caractérisation de membranes organiques par ellipsométrie sur flux diffus : Etude du colmatage

International audienc

Membrane characterization by optical methods: ellipsometry of the scattered fields

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