Nature Sub-Journal: Scientists develop brain organs with complex neural activity

Researchers at the UCLA Center for Regenerative Medicine and Stem Cell Research have developed brain organoids-3D brain structures grown from human stem cells-that show organized waves of activity similar to those of a living brain

Then, while studying organs cultured from stem cells of patients with neurological disorders with Rett syndrome, scientists were able to observe patterns of electrical activity similar to epilepsy, which is a feature of the disease

The study, published in the journal Nature Neuroscience, expands the brain conditions that can be studied in organoids and further illustrates the value of these human cell-based models in investigating the underlying causes of diseases and testing potential therapies

Bennett Novitch, a member of the Broad Stem Cell Research Center and senior author of the study, said: "This work proves that we can create a class similar to real human brain tissue.

In the past decade, researchers have discovered how to induce a person’s body cells, such as skin or blood cells, to become induced pluripotent stem cells in the laboratory.

This advancement allows scientists to study how a person’s cells differ from normal cells and perform experiments that are impossible in a living person—for example, manipulating the genes of kidney cells, or using lung organoids to study how COVID-19 is infected.

However, for the human brain, creating an organ that can mimic the complexity of the brain's structure is particularly challenging

These cells must also be connected to each other and function like neurons in the human brain

Dr.

After extracting a batch of brain organs from healthy people’s skin cells, Norwich, Samara Singh, and colleagues at the Center for Intelligence and Developmental Disabilities at UCLA used two different methods to study their bodies.

Some of the information they collect is similar to data that scientists usually find in brain scans called electroencephalograms (EEGs)

"I didn't anticipate the range of oscillation patterns we would see," said Norwich, who is also Ethel Scheibel, a professor of neuroscience at the University of California, Los Angeles

Next, the team used cells from patients with Rett syndrome to develop brain organs

When Novitch and Samarasinghe treated Rett's organoids with an experimental drug called Pifithrin-alpha, the epilepsy-related activity patterns disappeared and the organoids' neural activity became more normal

The use of organoids to study brain diseases is still limited, because organoids cannot replicate every aspect of the human brain—for example, they lack blood vessels—and they are more like early-developing brains than adult brains
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But the University of California, Los Angeles research shows that, despite this, they can still be used to test a wide range of brain functions, diseases, and drugs, which cannot be studied with brain cells in a petri dish
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Samarasinghe, who is also an assistant professor of neurology, said: "This is the first practical example of how drug testing works in brain organs
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" "We hope it can become a stepping stone to a better understanding of human brain biology and brain diseases
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Original search:

Identification of neural oscillations and epileptiform changes in human brain organoids

DOI 10.
1038 / s41593-021-00906-5