Link between autism and the mother's gut microbiome found
Researchers have now found that the gut microbiome doesn't just have a big impact on our own bodies. In mothers, the gut microbiome even affects their children and affects their risk of autism.
The University of Virginia School of Medicine scientists found in their current study that a mother's gut microbiome affects whether her children develop autism. The doctors published the results of their study in the English-language journal "Journal of Immunology".
What does our gut microbiome affect?
In recent years, more and more studies have been published, which show how fundamental the importance of our gut microbiome is for health. The gut microbiome has a major impact on the human body, for example, it influences our response to negative stimuli, our weight, our mental health and even the development of autoimmune diseases such as type 1 diabetes, the experts explain.
Gut microbiome affects the immune system
Animal experiments have shown a connection between the mother's gut microbiome and the development of autism in her offspring. The microbiome can shape the developing brain in a variety of ways, says study author John Lukens of the University of Virginia School of Medicine. The microbiome is very important for the calibration of how the immune system of the offspring will react to an infection, injury or stress, the doctor adds.
What is Interleukin-17a?
As far as autism is concerned, this compound appears to be due to a specific molecule called interleukin-17a (or IL-17a) that is produced by the immune system. The molecule has already been linked to conditions such as rheumatoid arthritis, multiple sclerosis and psoriasis. It also plays an important role in preventing infections, especially fungi. It is important that it can also influence the way the brain develops in the uterus, the scientists explain.
Trial was carried out on mice
To test their hypothesis that autism can be triggered by the IL-17a molecule, the research team blocked IL-17a in laboratory mice. The scientists used female mice from two separate laboratories. The first group of mice had microflora in the gut, which made them particularly susceptible to an IL-17a-induced inflammatory response. The remaining animals served as a control group. When the IL-17a molecule was artificially blocked (which prevented IL-17a-induced inflammatory reactions), the pups were born from both groups of mice with neurotypical behaviors. As a result, there was a neurological development in the offspring of the first group, which was similar to autism and had an impact on social and repetitive behavior.
Results were confirmed again
To confirm that this was due to the unique microflora of the group of animals, the researchers performed a faecal transplant on mice of the second group using the faeces of the mice of the first group. The researchers wanted to change the microflora of the second group to resemble the microflora of the first group of animals. And as already expected, the offspring of the second group also developed an autism-like neurological development, the experts explain.
Maternal intestinal health affects developmental disorders
Since these are animal studies, the results cannot simply be transferred to human pregnancies. Nevertheless, the study provides strong evidence that maternal intestinal health plays at least a role in the development of neurological development disorders.
More research is needed
In further investigations, it must now be checked whether a similar correlation can be found in humans. Various other molecules also need to be examined, because IL-17a could only be one piece in a much larger puzzle, according to study author Lukens. (as)