Simvastatin treatment reduces the cholesterol content of membrane/lipid rafts, implicating the N -methyl-D-aspartate receptor in anxiety: a literature review

Membrane/lipid rafts (MLRs) are plasmalemmal microdomains that are essential for neuronal signaling and synaptic development/stabilization. Inhibitors of 3-hydroxy-3-methylglutaryl-coenzyme-A reductase (statins) can disable the N-methyl-D-aspartate (NMDA) receptor through disruption of MLRs and, in turn, decrease NMDA-mediated anxiety. This hypothesis will contribute to understanding the critical roles of simvastatin in treating anxiety via the NMDA receptor

Efeitos da música clássica como elemento de enriquecimento ambiental em Mus musculus em cativeiro (Rodentia: Muridae)

No ambiente selvagem, os animais são submetidos a mudanças constantes nos estímulos sensoriais. Entretanto, o ambiente de cativeiro é muito mais pobre em termos de estímulos fornecidos aos animais alojados no seu interior. Numa tentativa de remediar esta situação e promover um melhor bem estar, camundongos (Mus musculus) foram expostos a duas condições: sem estímulos auditivos e com música clássica. Em todos os experimentos foi utilizada uma bateria de testes comportamentais. Os resultados demonstram uma diminuição significativa na imobilidade no nado forçado, aumento de entradas nos braços fechados do labirinto em cruz elevado e diminuição na imobilidade no campo aberto, nos animais que haviam sido pré-expostos anteriormente a 24h de música e sugerem que a música clássica causas mudanças na atividade motora em camundongos. Este estudo leva a conclusão que o enriquecimento do ambiente causa profundos efeitos sobre o comportamento de camundongos nos testes comportamentais e a música clássica é um método relativamente simples de contribuir para o bem estar de camundongos em cativeiro, mas pode comprometer resultados de experimentos como o nado forçado

Mate Tea Prevents Oxidative Stress in the Blood and Hippocampus of Rats with Acute or Chronic Ethanol Administration

Objective. The aim of this study was to evaluate the influence of acute and chronic intake of mate tea on the effects elicited by acute and chronic administration of ethanol. Methods. Oxidative stress was evaluated by measuring thiobarbituric acid-reactive substances (TBARS), as well as the activities of the antioxidant enzymes, catalase (CAT), glutathione peroxidase (GSH-Px), and superoxide dismutase (SOD) in the hippocampus and blood of rats. Male Wistar rats were randomly assigned to four groups, for both acute and chronic treatment: (1) control group, (2) treated group, (3) intoxicated group, (4) and intoxicated group treated with mate tea. Results. Both ethanol administrations significantly increased TBARS in plasma and hippocampus of rats and altered antioxidant enzyme activities, changes which were reverted by mate tea administration. Conclusions. Data indicate that acute and chronic ethanol administration induced oxidative stress in hippocampus and blood and that mate tea treatment was able to prevent this situation

Guanidinoacetate alters antioxidant defenses and butyrylcholinesterase activity in the blood of rats

Deficiency of guanidinoacetate methyltransferase, the first described creatine biosynthesis defect, leads to depletion of creatine and phosphocreatine, and accumulation of guanidinoacetate (GAA) in brain and body fluids. The present study aimed to investigate the influence of GAA on the activities of antioxidant enzymes, as well as on thiobarbituric acid-reactive substances (TBARS) and butyrylcholinesterase (BuChE) activity in the blood of rats. Results showed that GAA enhanced the activities of catalase (CAT) and glutathione peroxidase (GSH-Px) in the erythrocytes and BuChE activity. In addition, GAA enhanced TBARS levels in the plasma. Trolox (6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid), GSH (glutathione) and L-NAME (NG-nitro-L-arginine methyl ester) addition prevented the majority of alterations in oxidative stress parameters and the increase of BuChE activity that were caused by GAA. Data suggest that GAA alters antioxidant defenses and induces lipid peroxidation in the blood, as well altering BuChE activity. However, in the presence of trolox, GSH and L-NAME some of these alterations in oxidative stress and BuChE activity were prevented. Our findings lend support to a potential therapeutic strategy for this condition, which may include the use of appropriate antioxidants for ameliorating the damage caused by GAA

Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio