For many years, research on neurodegenerative diseases and spinal cord and brain injury has focused on damage to nerve cells, or neurons. Now, a new study of astrocytes - a type of cell that surrounds and supports neurons - finds that there is a subtype that can turn rogue and kill neurons, instead of helping to repair them during injury or disease.
The international study - conducted by a team that includes researchers from Stanford University School of Medicine in California, and the University of Melbourne in Australia - is published in the journal Nature.
The researchers suggest that the findings could lead to new treatments for brain injuries and major neurological disorders such as Alzheimer's and Parkinson's disease.
Lead author Dr. Shane Liddelow, of the department of pharmacology and therapeutics at Melbourne, and the department of neurobiology at Stanford, says that while astrocytes have often been described as "helper" cells, it has also been shown that they can become toxic and contribute to the damage caused by brain injury and disease by killing other brain cells.
"These apparently opposing effects have been a puzzle for some time. By characterizing two types of astrocytes this paper provides some answers to the puzzle," he adds.