Important factor for the development of the blood-brain barrier discovered
Researchers from Göttingen examined the long-known hunchback protein and found that the protein apparently plays a central role in the development of the blood-brain barrier. In fruit flies, the biologists demonstrated that the loss of protein function resulted in a failure of the blood-brain barrier. This barrier mainly ensures that the brain is supplied with nutrients and pollutants are kept away. The results provide new impetus for research into diseases in which the blood-brain barrier is impaired, such as multiple sclerosis and some types of stroke.
Biologists from the University of Göttingen have gained their knowledge of the hunchback protein from studies of the fruit fly Drosophila melanogaster. Although the experiments were carried out on flies, a comparison can be made with humans, because according to the scientists, the blood-brain barrier of the fruit fly is similar to that of humans. Special cells of very similar construction are responsible for the formation of this protective shell in various animal groups. The results of the study were recently published in the specialist journal "PLoS Genetics".
The function of the blood-brain barrier
The demarcation of the blood-brain barrier enables the blood in the nerve tissue of the brain to maintain a special milieu. This process is called homeostasis. The blood-brain barrier, which mainly consists of a barrier of endothelial cells, has important protective functions, such as defense against pathogens, toxins and messengers circulating in the blood. The function of the blood-brain barrier can be compared to a filter that allows the necessary nutrients to pass through, removes the metabolic products produced and blocks harmful substances.
Blood-brain barrier complicates drug treatments
With a variety of neurological diseases, the blood-brain barrier complicates drug treatment, since many active ingredients are blocked by the barrier and thus do not reach the desired goal. Many current research areas are concerned with overcoming the blood-brain barrier.
The fly's eye provided the crucial clue
Developmental biologists have long known hunchback protein as an important factor in embryonic development. Now, when examining the genes in the fruit flies eye, the Göttingen researchers discovered that many genes are also regulated by the hunchback protein. "Motivated by this discovery, we examined the function of the protein in more detail," explains lead author Montserrat Torres Oliva from the Johann Friedrich Blumenbach Institute for Zoology and Anthropology in a press release from the Georg August University of Göttingen regarding the study results.
The researchers switched off the blood-brain barrier in fly brains
First, the biologists observed that the hunchback protein is active in special glial cells. These migrate into the fly's eye, fulfill their function there and then leave the eye in the direction of the brain. "So far, what tasks the glial cells then perform was completely unclear," explains the head of the study, Dr. Nico Posnien.
No blood-brain barrier without the hunchback function
In further experiments, the scientists switched off the protein. "The loss of the hunchback function meant that the glial cells could no longer be formed correctly, and the blood-brain barrier was not intact in flies with incomplete glial cells," the scientists conclude. The results are new impulses for research into diseases in which the function of the blood-brain barrier is impaired. These include diseases such as multiple sclerosis and stroke. (vb)