Autism symptoms associated with astrocytes
Once implanted, the mice developed repetitive behaviors, a hallmark symptom of autism spectrum disorder (ASD), but they did not develop the social deficits associated with the disease. this. The mice also had memory impairment, which is common in ASD but is not a core feature of the disease.
“Our study shows that astrocyte abnormalities may contribute to the onset and progression of autism spectrum disorders,” said Dr. . “Astrocyte abnormalities can cause repetitive behavior or memory impairment, but not other symptoms such as difficulty with social interactions.”
Most research on autism spectrum disorders has focused on the role of neurons, a type of brain cell that relays information in the brain. But other brain cells, called astrocytes, help regulate the behavior of neurons and the connections between them. The genetic mutation associated with autism spectrum disorder has the potential to affect many different types of cells in the brain, says Dr. Post-mortem studies have revealed abnormalities in astrocytes in the brains of patients with autism spectrum disorders.
“We don’t know if these astrocyte abnormalities contribute to disease development or if those abnormalities are the result of disease,” says Dr.
To determine if astrocytes might be involved early in the disease, the team took stem cells taken from patients with autism spectrum disorder, coaxed them to develop into stem cells. astrocytes in the lab and transplant them into the brains of otherwise healthy newborn mice, creating a human. -mouse chimera.
Using a microscopy technique called two-photon imaging, explains Dr. Ben Huang at Weill Cornell Medicine, they observed excessive calcium signals in human astrocytes implanted in mouse brains.
Dr Huang said: “It is amazing to see how human astrocytes respond to behavioral changes in active mice. “We believe we are the first to record the activity of transplanted human astrocytes in this way.”
To determine whether an increase in calcium signaling causes behavioral symptoms in the mice, the team infected astrocytes grown from stem cells of ASD patients in the laboratory. with a virus carrying an RNA fragment designed to reduce calcium signaling to normal levels. When they transplanted these astrocytes into mice, the animals did not develop memory problems.
“Future therapies for autism could exploit this finding by using genetic tools to limit extreme fluctuations in calcium within cells,” said Megan Allen at Weill Cornell Medicine. star cytoskeleton”.
“It is important to define the role of specific types of brain cells, including astrocytes, in neurodevelopmental and neuropsychiatric diseases,” she said.