are connected through the ‘gut-brain axis'.
Anatomy Image/ Shutterstock
One of the most important microbiomes in our body is our gut microbiome. It helps us maintain overall wellbeing by helping us to absorb all the vitamins and minerals from the food we eat.
But when our gut microbiome's balance becomes disrupted, from things like,
...it can not only result in digestion and gut problems, but has even been linked to,
This shows us that it might be time to look outside the skull to understand the cause of some brain conditions.
They communicate with each other through the system known as the gut-brain (or brain-gut) axis.
This axis influences the digestive system's activity and plays a role in appetite and the type of food we prefer to eat. It's made up of brain cells (neurons), hormones, and proteins that allow the brain to send messages to the gut (and vice versa).
One way they do this is by making proteins that carry messages to the brain.
The microbiome can also influence brain activity through the vagus nerve, one of the brain's 12 cranial nerve pairs.
This nerve snakes through the body connecting internal organs - including the gut - to the brainstem at the base of the brain. In this way, the vagus nerve provides a physical pathway between the gut and brain, enabling a different route to the chemical pathways of the gut-brain axis for communication between brain and gut.
Through this connection, an unhealthy microbiome can transmit harmful pathogens and abnormal proteins to the brain, where they may spread.
When the microbiome becomes unbalanced, the first sign is usually digestive problems,
Symptoms can include,
...and other gut-based metabolic changes.
Immune response and normal bodily functions such as liver, heart and kidney function may also be negatively affected by dysbiosis.
Dysbiosis can be reversed depending upon cause.
For example, a stomach bug or poor diet can be more easily fixed than disease a or illness such as cancer, obesity, or diabetes.
A healthy diet may fix
gut dysbiosis in some instances.
Anna Kucher/ Shutterstock
Scientists have investigated the impact of dysbiosis on different neurological disorders, including,
...disease, and multiple sclerosis, with early research finding a link between the two.
For example, researchers found that in patients with Parkinson's disease gut dysbiosis, often as constipation, is common.
Gut problems may be present several decades before typical symptoms appear, with evidence showing the microbiome is altered early in the condition.
All of this early research suggests a disrupted microbiome contributes to the development of neurological disorders by negatively affecting the gut-brain axis.
It does this by transmitting abnormal proteins and pathogens along the vagal nerve route. However, the initial cause of microbiome disruption in those with neurological conditions is not yet known.
But on a positive note, our gut microbiome can be modified:
...can all bolster our gut microbiome's health.
It's currently uncertain whether daily probiotic use can help prevent neurological diseases, which is something we're currently investigating. We are the first team to investigate probiotic use in Parkinson's disease patients to study their microbiome before and after use.
As our knowledge increases, microbiome-targeted therapies might present a new way of treating or minimizing diseases.
Probiotic use is a promising approach because there are few adverse effects, medications are likely to be better absorbed in a healthier gut environment, it's less complicated than changing your diet, and is quick and easy to implement.
It is early days, and there is still much to learn, but based on current research it appears that gut microbiome health is more intimately tied to our brain health than we imagine...