Introducing the brain: a study of blood brain barrier cells (Introduction)

by David Turell , Tuesday, February 15, 2022, 17:07 (1010 days ago) @ David Turell

The barrier is very real and apparently very necessary to exist. The cells that do it are difficult to isolate:

https://medicalxpress.com/news/2022-02-atlas-cells-blood-brain.html

"Those cells, which comprise only 0.3 percent of the brain's cells, also make up the blood-brain barrier, a critical interface that prevents pathogens and toxins from entering the brain, while allowing critical nutrients and signals through.

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"Their study also revealed differences between cerebrovascular cells from healthy people and people suffering from Huntington's disease, which could offer new targets for potential ways to treat Huntington's disease. Breakdown of the blood-brain barrier is associated with Huntington's and many other neurodegenerative diseases, and often occurs years before any other symptoms appear.

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"Cerebrovascular cells make up the network of blood vessels that deliver oxygen and nutrients to the brain, and they also help to clear out debris and metabolites. Dysfunction of this irrigation system is believed to contribute to the buildup of harmful effects seen in Huntington's disease, Alzheimer's, and other neurodegenerative diseases.

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"The researchers performed single-cell RNA-sequencing on more than 16,000 cerebrovascular cells, and used the cells' gene-expression patterns to classify them into 11 different subtypes. These types included endothelial cells, which line the blood vessels; mural cells, which include pericytes, found in the walls of capillaries, and smooth muscle cells, which help regulate blood pressure and flow; and fibroblasts, a type of structural cell. (my bold)

""This study allowed us to zoom in to this incredibly central cell type that facilitates all of the functioning of the brain," Kellis says. "What we've done here is understand these building blocks and this diversity of cell types that make up the vasculature in unprecedented resolution, across hundreds of individuals."

"The researchers also found evidence for a phenomenon known as zonation. This means that the endothelial cells that line the blood vessels express different genes depending on where they are located—in an arteriole, capillary, or venule. Furthermore, among the hundreds of genes they identified that are expressed differently in the three zones, only about 10 percent of them are the same as the zonated genes that have been previously seen in the mouse cerebrovasculature.

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"Because cerebrovascular cells can be accessed through the bloodstream, they could make an enticing target for possible treatments for Huntington's and other neurodegenerative diseases, Heiman says. The researchers now plan to test whether they might be able to deliver potential drugs or gene therapy to these cells, and study what therapeutic effect they might have, in mouse models of Huntington's disease.

"'Given that cerebrovascular dysfunction arises years before more disease-specific symptoms, perhaps it's an enabling factor for disease progression," Heiman says. "If that's true, and we can prevent that, that could be an important therapeutic opportunity.'"

Comment: a highly designed system, not by chance. And as usual looking to correct metabolic errors. Our high-speed living biochemistry causes occasional mistakes, as previously noted.