Long-Term Gene Therapy Causes Transgene-Specific Changes in the Morphology of Regenerating Retinal Ganglion Cells

Recombinant adeno-associated viral (rAAV) vectors can be used to introduce neurotrophic genes into injured CNS neurons, promoting survival and axonal regeneration. Gene therapy holds much promise for the treatment of neurotrauma and neurodegenerative diseases; however, neurotrophic factors are known to alter dendritic architecture, and thus we set out to determine whether such transgenes also change the morphology of transduced neurons. We compared changes in dendritic morphology of regenerating adult rat retinal ganglion cells (RGCs) after long-term transduction with rAAV2 encoding: (i) green fluorescent protein (GFP), or (ii) bi-cistronic vectors encoding GFP and ciliary neurotrophic factor (CNTF), brain-derived neurotrophic factor (BDNF) or growth-associated protein-43 (GAP43). To enhance regeneration, rats received an autologous peripheral nerve graft onto the cut optic nerve of each rAAV2 injected eye. After 5–8 months, RGCs with regenerated axons were retrogradely labeled with fluorogold (FG). Live retinal wholemounts were prepared and GFP positive (transduced) or GFP negative (non-transduced) RGCs injected iontophoretically with 2% lucifer yellow. Dendritic morphology was analyzed using Neurolucida software. Significant changes in dendritic architecture were found, in both transduced and non-transduced populations. Multivariate analysis revealed that transgenic BDNF increased dendritic field area whereas GAP43 increased dendritic complexity. CNTF decreased complexity but only in a subset of RGCs. Sholl analysis showed changes in dendritic branching in rAAV2-BDNF-GFP and rAAV2-CNTF-GFP groups and the proportion of FG positive RGCs with aberrant morphology tripled in these groups compared to controls. RGCs in all transgene groups displayed abnormal stratification. Thus in addition to promoting cell survival and axonal regeneration, vector-mediated expression of neurotrophic factors has measurable, gene-specific effects on the morphology of injured adult neurons. Such changes will likely alter the functional properties of neurons and may need to be considered when designing vector-based protocols for the treatment of neurotrauma and neurodegeneration

Biomarqueurs métaboliques de toxicité du cadmium chez le maïs (Zea mays L.). Mécanismes de tolérance, relations dose-effet et précocité de la réponse

*INRA, Centre de Recherches de Bordeaux. Unité d'Agronomie (FRA) Diffusion du document : INRA, Centre de Recherches de Bordeaux. Unité d'Agronomie (FRA) Diplôme : Dr. d'Universit

Assessment of the phytotoxicity of cadmium contaminated soils by an ecotoxicological biotest using maize metabolic biomarkers

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La consommation d’eau des élevages ovins laitiers en Aveyron

National audienceLes activités liées à l’agriculture sont souvent montrées du doigt pour les prélèvements qu’elles exercent sur la ressource en eau. En ce qui concerne les filières animales et en particulier l’élevage ovins, peu de données sont disponibles pour permettre d’alimenter ces évaluations et d’appréhender les volumes et les conditions d’utilisation de l'eau en élevage. L’Institut de l’Elevage en partenariat avec les chambres d’agriculture, le CNBL (Comité National Brebis laitières), l’INRA (Institut National de la Recherche Agronomique) a mené un programme de recherche sur trois ans (2009/ 2011) portant sur la consommation d’eau des élevages ovins dans le cadre d’un financement du Ministère de l’Alimentation, de l’Agriculture et de la Pêche (CASDAR). L’objectif de cette étude a été de construire un référentiel des consommations d’eau des élevages, afin, in fine, d’élaborer une méthode de diagnostic pour prévoir les quantités d’eau utilisée

Responses to cadmium in leaves of transformed poplars overexpressing Y-glutamylcysteine synthetase

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Responses to cadmium in leaves of transformed poplars overexpressing gamma-glutamylcysteine synthetase

Poplars overexpressing a bacterial gamma-glutamylcysteine synthetase (gamma-ECS) in the cytosol (lines ggs11 and ggs28) had a 30-fold increase in foliar gamma-ECS activity relative to untransformed controls. Foliar gamma-glutamylcysteine (gamma-EC) was increased by 10-fold while foliar glutathione accumulation increased by up to 3.5-fold in the leaves of the transformants, Untransformed and transformed poplars were grown with different soil concentrations of cadmium (0-1100 mu g g(-1) soil) for 2 weeks. Cadmium accumulated in the leaves of both transformed and untransformed poplars and growth was inhibited. Growth inhibition and foliar cadmium accumulation were greatest at the highest soil cadmium concentrations in all lines. Exposure to cadmium enhanced the foliar cysteine, gamma-EC and glutathione pools in all lines but less glutathione was present in the leaves of the untransformed controls than the transformants under all growth conditions. Cadmium-induced changes in the activities of malic enzyme, isocitrate dehydrogenase and guaiacol peroxidase were less pronounced in the leaves of the transformed poplars overexpressing gamma-ECS than in the untransformed controls. Glutamate dehydrogenase and glutathione reductase activities were unchanged by exposure to cadmium. We conclude that overexpression of gamma-ECS activity and foliar glutathione accumulation in transformed poplar allows greater tissue cadmium accumulation but has only a marginal effect on cadmium tolerance in poplar

Characterization of dairy sheep and goats production systems in France: first step for a G×E study

In a fluctuating economic, environmental and societal context, farms of dairy small ruminants attempt to increase their autonomy in feed resources. Due to the diversity of soil and climate conditions in France, breeders develop diverse farming and feeding strategies. In order to investigate presence of G×E interactions, the first step consisted in describing dairy sheep and goats production systems to identify contrasted farms typologies. An exploration was carried out using a large set of variables present in the databases of milk-recording, genetic evaluation, technical support (describing farming and feeding systems, when available), and also geographical and meteorological data (METEOFRANCE, French official service of meteorology and climatology). The most discriminating variables were selected to conduct a multiple correspondence analysis. A classification of herds was then performed within geographic areas for sheep (440, 463 and 98 herds in Roquefort area, Western Pyrenean, and Corsica island, respectively), and within all the country for goats (1,136 herds, whose 514 in the breeding nucleus). For dairy sheep in the Roquefort area, 4 clusters of flocks in Lacaune breed were identified according to their geographical location, precocity of grass growth (in relation to altitude), and amounts of concentrate and forages distributed. In the Western Pyrenean area, 4 clusters in Basco-Béarnaise breed and 7 clusters in Blond-faced Manech breed have been highlighted on the basis of their location-altitude and of herd management criteria (rate of first lactations at 2 years, flock size). In Corsica, the study has highlighted 3 groups of flocks according to their altitude and level of production (linked to the artificial insemination rate). For goats, 4 clusters of herds were discriminated according to area of production (West / East gradient), breeding goals (fat and protein contents or milk yield), system of sales (cheese maker or deliverer to dairy industry), herd size and reproduction organization (out of season or not)