Microbiome can directly influence nervous system (!)
That there is a relationship between the gut and the brain is not new (1). Since 2014, almost 2000 publications have been published. In February 2020, Nature published research demonstrating a direct link between the microbiome and the nervous system in the gut (2,3). The researchers identified a receptor that is an intrinsic part of the nervous system in the gut and showed that microorganisms in the gut can directly express this receptor (3). This affects functions of the local neural network, such as peristalsis, but through the connection of the vagus nerve, this receptor also provides a direct link between the microbiome and the brain.
Role of the microbiome in autism
There are strong suspicions that autism spectrum disorder is related to gut health. Autistic children often have intestinal complaints such as chronic diarrhea or constipation (4,5) and belong to the group of children most often referred to an MDL doctor (5). In autistic people there is evidence of increased intestinal permeability (6) and elevated levels of an endotoxin of bacterial origin (LPS) are found in the blood (7). A small study with faecal transplantation in autistic children resulted not only in greatly reduced intestinal complaints, but also in significantly improved behavioral scores (8). This effect was still present two years later (9). Recent pilot studies with pre- and probiotics also show tentative improvements in behavioral scores (10,11).
References:
- https://doi.org/10.1152/physrev.00018.2018
- https://www.nrc.nl/nieuws/2020/02/12/bacterien-communiceren-met-zenuwstelsel-in-de-darm-a3990193
- https://doi.org/10.1038/s41586-020-1975-8
- https://doi.org/10.1007/s10803-013-1973-x
- https://doi.org/10.3748/wjg.v22.i46.10093
- https://doi.org/10.3390/ijms20092115
- https://doi.org/10.3748/wjg.v22.i1.361
- https://doi.org/10.1186/s40168-016-0225-7
- https://doi.org/10.1038/s41598-019-42183-0
- https://doi.org/10.1186/s40168-018-0523-3
- https://doi.org/10.3390/nu11040820