Neurons have been created from a different type of brain cell that usually supports them. Nerve cell death is a hallmark of Alzheimer’s disease, but a cage of nanoparticles containing antibodies converted astrocytes, another type of brain cell, into neurons in mice with a version of the condition. This boosted the mice’s cognitive skills.
The researchers behind the approach hope to test it in people in the next few years. Alzheimer’s, stroke, depression: The preventative power of sauna In Alzheimer’s disease, which affects around 24 million people worldwide, the proteins beta-amyloid and tau misfold and form clumps, known as plaques and tangles. This leads to neuroinflammation and, ultimately, nerve cell death.
Researchers are increasingly exploring whether stimulating the growth of new neurons could treat Alzheimer’s disease and other neurodegenerative conditions. For instance, in 2020, scientists discovered that astrocytes – star-shaped cells that help neurons function – can be converted into neurons in the brains of mice with a version of Parkinson’s disease, which improved their motor skills. This involved using CRISPR to genetically engineer the mice to deplete levels of a protein called PTBP1.
This usually acts like a master switch that stops astrocytes from turning into neurons. But such genetic approaches can alter regions of the genome you didn’t intend to target. To address this issue, he and his colleagues have developed another way to deplete PTBP1.
They designed a drug called TN-PTBP1 that packages PTBP1-targeting antibodies within a cage of nanoparticles that shuttles them across the blood-brain barrier. The drug enters cells in the brain, including astrocytes, where the antibodies bind to and substantially deplete PTBP1. After about a week, the antibodies are recycled by the cell, says Xu.
The team has now tested this in brain organoids made up of clumps of astrocytes and neurons, which were grown from human stem cells in a lab dish. This showed that TN-PTBP1 converts astrocytes into neurons. Next, the researchers tried the approach in 12 mice that had been genetically engineered to develop a condition mimicking Alzheimer’s.
Extract — continue reading at the source.
