162 Such a mechanism may contribute to trap glutamine in astrocytes and promote swelling. In contrast with its acute form, chronic hepatic encephalopathy, which is associated with more modest increases in brain ammonia, does not result in overt cerebral edema,163 suggesting the existence of compensatory mechanisms taking place in astrocytes in order to

prevent excessive swelling. This is thought to be accomplished by the release of osmolytes such as taurine and myo-inositol by astrocytes in response to glutamine accumulation. However, it appears that when osmolyte pools Inhibitors,research,lifescience,medical are depleted as a result of excessive hyperammonemia, for example during acute liver failure, this protective mechanism is exhausted and astrocytes swell as a result. This, together with an impaired capacity of astrocytes to fulfill their role in ammonia detoxification, seriously compromises brain function in acute liver

failure. Conclusion Astrocytes Inhibitors,research,lifescience,medical are known to be the most important neural cell type for the maintenance of brain click here homeostasis. It is safe to assume that, as technology advances in the years to come, we will continue to uncover the multiple facets of astroglia. It has already become quite clear however that it is unrealistic to approach brain Inhibitors,research,lifescience,medical function and dysfunction from a uniquely neuronal standpoint. Because of their involvement in such a wide range of homeostatic functions, any brain insult is likely to have an impact on astrocytes. Their capacity to adapt to these changes Inhibitors,research,lifescience,medical weighs heavily in the fine balance between neuroprotection and neurotoxicity as illustrated by the three neuropathological conditions discussed above. In this context, understanding astrocytic function is key to providing a better grasp of brain function in general and how it may go awry. This may lead to the identification Inhibitors,research,lifescience,medical of

better suited therapeutic targets, as they should take into account the multiple interactions and interdependencies between neural cell types. Acknowledgments Acknowledgements: The authors wish to thank Drs Igor Allaman and Nicolas Aznavour for their help with the manuscript. Work in Parvulin PJM’s laboratory is supported by the Swiss National Science Foundation (grant no. 3100AO-108336/1 to PJM). MB was supported by the Fonds de la Recherche en Santé du Québec (FRSQ). Selected abbreviations and acronyms Aβ amyloid-beta AD Alzheimer’s disease GSH glutathione MCT monocarboxylate transporter ROS reactive oxygen species
Amphetamines and ring substituted methylenedioxyamphetamines are the most commonly used illicit drugs after cannabis. Amphetamines are psychostimulants, and methylenedioxyamphetamines are entactogens – psychoactive drugs with emotional and social effects.