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401.
Rosalia Crupi Daniela Impellizzeri Marika Cordaro Rosalba Siracusa Giovanna Casili Maurizio Evangelista Salvatore Cuzzocrea 《Molecular neurobiology》2018,55(11):8455-8472
Parkinson’s disease (PD) is a neurodegenerative disease characterized by degeneration of dopaminergic neurons. Aging is a major risk factor for idiopathic PD. Several prior studies examined the neuroprotective effects of palmitoylethanolamide (PEA), alone or combined with antioxidants, in a model of PD induced by the dopaminergic toxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). Here, we analyzed the pretreatment effect of micronized PEA (PEAm) on neuroinflammation and neuronal cell death in the MPTP model. Male CD mice (21 months of age) were pre-treated for 60 days with PEAm. After this time, they received four intraperitoneal injections of MPTP over a 24-h period and were killed 7 days later. On the 8th day, brains were processed. Pretreatment with PEAm ameliorated behavioral deficits and the reductions in expression of tyrosine hydroxylase and dopamine transporter, while blunting the upregulation of α-synuclein and β3-tubulin in the substantia nigra after MPTP induction. Moreover, PEAm reduced proinflammatory cytokine expression and showed a pro-neurogenic effect in hippocampus. These findings propose this strategy as a valid approach to prevent neurodegenerative diseases associated with old age. 相似文献
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We studied diet selection of the globally threatened lesser white-fronted goose Anser eythropus at a spring staging area on the island of Hailuoto (64°00'N, 24°45'E), off the western coast of Finland. We determined the diet using droppings, which were collected in late May, when the geese had left the area and migrated northwards. The sample potentially comprised of ejecta from 31 different individuals. Plant idengification was based on visual determination of epidermal fragments. A total of 100 droppings were sampled using a point quadrat method. We calculated the percentage of each idengified taxon in each dropping and related this to the availability of the corresponding taxon in the meadow. We measured preference for each taxon using Chesson's electivity index (ɛi ) and tested them by bootstrap resampling. The diet contained 9 taxa of the ca 40 available. Almost all dietary items were Monocotyledons (99.9%), mostly grasses (88.7%) including Festuca rubra (43%), Phragmites australis (30%) and Calamagrostis stricta (13%). Only Phragmites (ɛ=0.73, p=0.000), Festuca (ɛ=0.52, p=0.004) and possibly Triglochin palustris (ɛ=0.70, p=0.125) were preferred, all other species were avoided. All preferred species were quite common and other goose species exploit them too. The lesser white-fronted geese preferred large natural meadows that were five times broader than an "average" Bothnian Bay meadow. All forms of mowing and grazing management benefit the restoration of lesser white-fronted goose habitats at the landscape level. Festuca and especially Triglochin benefit from such management. Reeds, Phragmites , whose spread has been the main cause of coastal meadow deterioration, can be controlled by management, but can also be maintained among other vegetation if mowing is less frequent or grazing not too intensive. 相似文献
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