Previously unknown interactions between the lungs and the brain
the Lunge is our most important exchange surface with the environment when it comes to the supply of oxygen. A microbial flora that has been little researched so far is located at this transition, which is referred to as the lung microbiome. A German research team has now for the first time been able to establish a close relationship between this microbiome and the brain point out
Researchers from the Institute for Neuroimmunology and Multiple Sclerosis Research at the University Medical Center Göttingen (UMG) documented for the first time how the microbial flora of the lungs controls the immune readiness of the brain. These interactions might also be the cause of destructive autoimmune inflammation. The results of the research work were recently published in the renowned journal “Nature” released.
Lung flora examined closely for the first time
All contact surfaces that connect people with the outside world are colonized by bacteria. As part of the current study, the UMG working group found out that the bacterial colonization of the lungs at the contact surface between the lung tissue and the breathing air plays a special role.
Lung microbiome is more influential than previously thought
The team establishes a new and unexpected functional connection between the lungs and the brain. Accordingly, the lung microbiome sends constant signals to the brain, causing so-called Microglia to be influenced. The microglia can be thought of as the “immune cells of the brain”.
“The microglia adapt their immunological reactivity according to these microbial signals and can therefore react in good time to impending dangers,” explains study lead author Dr. Leon Hosang.
Lung microbiome as an early warning system for the brain
“The lung microbiome therefore acts as a species early warning system for the sensitive brain tissue,” adds Professor Dr. Francesca Odoardi, who together with Professor Dr. Alexander Flügel heads the research project.
According to the research team, this hitherto little-studied connection between the lungs and the brain can have far-reaching effects on health. For example, lung infections, antibiotic treatments, air pollution and climatic changes can change the lung flora and thus the immune activity within the brain.
The lung flora is rather small compared to the intestinal flora
Numerous researches in recent years have dealt with the influence of the intestinal flora on human health. In comparison, according to the research team, the number of studies on the microbiome in the lungs is relatively small.
Possible cause of autoimmune diseases
In fact, for a long time it was believed that the lungs had no flora at all and were sterile. The working group from Göttingen not only showed that the lung flora is more influential than previously thought, but also that the smallest changes in this microbiome increase the susceptibility of the brain to autoimmune diseases change.
Antibiotics put the brain on alert
For example, the researchers were able to document how the lung microbiome sent a signal to the brain following the administration of antibiotics, which put the microglia in the brain on alert. According to the working group, “antibiotic-mediated manipulation of the lung microbiome was associated with clearly measurable and even microscopically visible changes in the microglia”.
In addition, according to the study, the microglia reacted less strongly to inflammatory signals, which resulted in reduced recruitment of immune cells into the inflamed brain tissue. “This explains the reduced susceptibility to autoimmune inflammation very conclusively,” the scientists conclude.
New approach to therapies
According to the researchers, the microglia were paralyzed following the administration of antibiotics. The origin of this reaction might be traced back to a certain type of bacteria in the lungs that produce a special cell wall component called lipopolysaccharide.
After the administration of antibiotics, this cell wall component accumulated more in the lungs. The increased amount of lipopolysaccharide then led to the “paralysis” of the microglia in the brain. A reduction in lipopolysaccharide in the lungs, on the other hand, had the effect of increasing autoimmune processes in the brain.
“Possibly this new lung-brain axis even use it therapeutically,” suspects Professor Flügel. A targeted administration of probiotics or certain antibiotics is conceivable in order to specifically influence the immune reactions in the brain.
This might be the case, for example, in the treatment of Multiple Sclerosis play a role, but also in general in all diseases of the central nervous system in which microglia are involved.
Similar effects through the gut-brain axis
Just recently, another study showed a similar connection between the gut microbiome and immune responses in the brain. For more information, see the article “The gut-brain axis opens up new therapeutic approaches for cancer and autoimmune diseases“. (vb)
Author and source information
This text corresponds to the specifications of medical specialist literature, medical guidelines and current studies and has been checked by medical professionals.
Author:
Diploma-Editor (FH) Volker Blasek
Swell:
- Universitätsmedizin Göttingen: Lung-brain axis: the microbial flora of the lungs controls the immune readiness of the brain (published: February 24th, 2022), umg.eu
- Hosang, L., Canals, R.C., van der Flier, F.J. et al. The lung microbiome regulates brain autoimmunity. Nature (2022). https://doi.org/10.1038/s41586-022-04427-4, nature.com
- Hiltensperger, M., Beltrán, E., Kant, R. et al. Skin and gut imprinted helper T cell subsets exhibit distinct functional phenotypes in central nervous system autoimmunity: in: Nature Immunology (2021), nature.com
Important NOTE:
This article contains general advice only and should not be used for self-diagnosis or treatment. He can not substitute a visit at the doctor.
