Land use functions — a multifunctionality approach to assess the impact of land use changes on land use sustainability

Part 5. Regional and local evaluation - 17; International audience; The dramatic changes in land use observed in Europe in the last fifty years have generally resulted in improvement of human welfare and economic development. On the other hand, they have caused serious environmental problems. There is therefore a need for approaches that help to understand in an integrative way the economic, environmental and societal impacts that land use changes have on sustainability. Sustainability Impact Assessment(SIA), which assesses the impact of policies on sustainability, addresses this challenge. SIA partly builds on the concept of the multifunctionality of land which helps to deal with the compl…

Acetylcholine release in the hippocampus of the urethane anaesthetised rat positively correlates with both peak theta frequency and relative power in the theta band.

The need to achieve a clearer understanding of relations between hippocampal theta characteristics and cholinergic septohippocampal neuron activity, prompted us to re-examine, in the urethane-anaesthetised rat, the statistical relationships between the electrophysiological and neurochemical variables using a procedure which is believed to enhance significantly the degree of confidence with which parameters of theta recorded with classic macroelectrodes can be related to concomitant acetylcholine output measured by high-performance liquid chromatography with electrochemical detection. Firstly, the theta rhythm and the acetylcholine content were derived from the same hippocampus. Secondly, th…

Cerebrospinal fluid choline levels in Parkinson's disease

Temporal changes in free iron levels after brain ischemia

Whereas iron chelators have been proposed as therapeutic agents in stroke, changes in free iron levels have never been explored after focal brain ischemia. Therefore, free and total iron levels in cortical tissue and free iron levels in plasma were measured before and after (1, 4 and 24h) photothrombotic occlusion of cortical vessels in rats. Brain ferritin expression and localization were also investigated before and after (24, 72 and 192 h) occlusion. The results showed that free iron remained below detectable levels in plasma and that the lesion exhibited high levels of free and total iron. As compared to contralateral values, free iron levels in ischemic core and penumbra increased (+50…

Ipsilateral versus contralateral spontaneous post-stroke neuroplastic changes: involvement of BDNF?

International audience; Stroke is a leading cause of death and disability in industrialized countries. Although surviving patients exhibit a certain degree of restoration of function attributable to brain plasticity, the majority of stroke survivors has to struggle with persisting deficits. In order to potentiate post-stroke recovery, several rehabilitation therapies have been undertaken and many experimental studies have reported that brain-derived neurotrophic factor (BDNF) is central to many facets of neuroplastic processes. However, although BDNF role in brain plasticity is well characterized through strategies that manipulate its content, the involvement of this neurotrophin in spontan…

Time-dependent contribution of non neuronal cells to BDNF production after ischemic stroke in rats.

International audience; Although brain-derived neurotrophic factor (BDNF) plays a central role in recovery after cerebral ischemia, little is known about cells involved in BDNF production after stroke. The present study testes the hypothesis that neurons are not the unique source of neosynthesized BDNF after stroke and that non neuronal-BDNF producing cells differ according to the delay after stroke induction. For this purpose, cellular localization of BDNF and BDNF content of each hemisphere were analysed in parallel before and after (4h, 24h and 8d) ischemic stroke in rats. Stroke of different severities was induced by embolization of the brain with variable number of calibrated microsphe…

Microglial involvement in neuroplastic changes following focal brain ischemia in rats.

The pathogenesis of ischemic stroke is a complex sequence of events including inflammatory reaction, for which the microglia appears to be a major cellular contributor. However, whether post-ischemic activation of microglial cells has beneficial or detrimental effects remains to be elucidated, in particular on long term brain plasticity events. The objective of our study was to determine, through modulation of post-stroke inflammatory response, to what extent microglial cells are involved in some specific events of neuronal plasticity, neurite outgrowth and synaptogenesis. Since microglia is a source of neurotrophic factors, the identification of the brain-derived neurophic factor (BDNF) as…

''Comparative Effect of Treadmill Exercise on Mature BDNF Production in Control versus Stroke Rats''

Quirie, Aurore | Hervieu, Marie | Garnier, Philippe | Demougeot, Celine | Mossiat, Claude | Bertrand, Nathalie | Martin, Alain | Marie, Christine | Prigent-Tessier, Anne; International audience; ''Physical exercise constitutes an innovative strategy to treat deficits associated with stroke through the promotion of BDNF-dependent neuroplasticity. However, there is no consensus on the optimal intensity/duration of exercise. In addition, whether previous stroke changes the effect of exercise on the brain is not known. Therefore, the present study compared the effects of a clinically-relevant form of exercise on cerebral BDNF levels and localization in control versus stroke rats. For this purpo…

''Effect of stroke on arginase expression and localization in the rat brain''

Quirie, Aurore | Demougeot, C. Eline | Bertrand, Nathalie | Mossiat, Claude | Garnier, Philippe | Marie, Christine | Prigent-Tessier, Anne; International audience; ''Because arginase and nitric oxide (NO) synthases (NOS) compete to degrade l-arginine, arginase plays a crucial role in the modulation of NO production. Moreover, the arginase 1 isoform is a marker of M2 phenotype macrophages that play a key role in tissue remodeling and resolution of inflammation. While NO has been extensively investigated in ischemic stroke, the effect of stroke on the arginase pathway is unknown. The present study focuses on arginase expression/activity and localization before and after (1, 8, 15 and 30days) …

Limits and targets for a regional sustainability assessment: an interdisciplinary exploration of the threshold concept

Part 5. Regional and local evaluation-18 ; International audience; Some encompassing terminology is required in order to accommodate different conceptual approaches in the three pillars of sustainability. So, this chapter provides a literature review exploring the threshold concept. In environmental research – especially in ecology – thresholds are often associated with limits which have certain system-inherent processes. In social and economic disciplines, if the notion of limit or critical limit is present, the concept of targets is often more appropriate which are linked to political objectives and social acceptability. The concept of threshold is accommodated within the general framewor…

Beneficial effect of dipyridyl, a liposoluble iron chelator against focal cerebral ischemia: In vivo and in vitro evidence of protection of cerebral endothelial cells

Whereas iron chelators were shown to induce neuroprotection against brain injury, the effect of iron chelators on ischemia-induced damage of cerebral endothelium is largely unknown. Our objective was to explore the endothelioprotective effect of the lipophilic iron chelator dipyridyl (DP) (i) in vitro on the death of cerebral endothelial cells (CECs) subjected to intracellular iron loading and (ii) in vivo on the ischemia-induced blood-brain barrier (BBB) disruption. When given shortly after iron exposure or brain ischemia, DP prevented the death of CECs and diminished BBB disruption, respectively, whereas a delayed administration of DP was associated with a lower CECs protection. Interesti…