Our bodies contain more than just our own human cells. We normally live in harmony with a vast array of microorganisms occupying specific spaces, or niches, on and within us. These bacteria, fungi, viruses, and protozoa form the human microbiome. The ones in the gut, mainly within the colon (large intestine), normally maintain a health balance and keep “bad” microbes from overpopulating that area of the digestive system. The normal gut organisms, consisting of around 1,000 different species of bacteria as well as other microbes, outnumber all the human cells in our bodies.

 

The gut microbiome acts locally and systemically, meaning it interacts with other parts of the body. Locally in the gut, the microbiome digests foods, helps to regulate the immune system, and produces vitamins that our bodies need for metabolism, nerve function, and blood clotting but that they cannot produce on their own.

 

There is mounting evidence that the gut microbiome also interacts with the nervous system, including the brain, in health and disease. Its effects also reach beyond the gut. Evidence points to a role for it in the faulty regulation of the immune system, leading to such diseases as rheumatoid arthritis, multiple sclerosis, diabetes, and allergies.

 

In this episode, Ai Huey Tan of the University of Malaya in Kuala Lumpur, Malaysia discusses what is known about the role of the gut microbiome as it affects Parkinson’s disease and its treatment and what researchers are continuing to investigate.