Non-cell Autonomous Degeneration: Role of Astrocytes in Neurodegenerative Diseases. Role of Astrocytes in Neurodegenerative Diseases.

Astrocytes, representing the most abundant glial cells in the central nervous system, regulate the development and function of neurons. Accumulating evidence suggests that astrocytes also play pivotal roles in the pathogenesis of neurodegenerative diseases, once thought to selectively afflict neurons. In response to disease or injury, astrocytes become reactive with profound morphological and transcriptomic alterations. Some changes in reactive astrocyte morphology and function are thought to be beneficial. Other responses in reactive astrocytes contribute to neuronal degeneration. In this chapter, we review evidence for astrocyte-dependent non-cell autonomous degeneration of neurons in Amyotrophic lateral sclerosis, Alzheimer's disease, Parkinson's disease, Huntington's disease, and spinocerebellar ataxia type 7. We also highlight recent advances in our understanding of glial cell-intrinsic mechanisms that underlie neurodegenerative diseases. These studies are laying the foundation for development of novel therapies in the treatment of neurodegenerative diseases.