We’re talking fecal transplants, probiotics, gut flora and more this week. Do bacteria in your GI tract affect your moods? How does your microbiome affect your overall health? We visit the lab of computational biologist Dr. Jose Clemente where he and his team study the efficacy of fecal transplants in patients with Irritable Bowel Disease.
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A few questions for Dr. Clemente
What is the microbiome?
The microbiome is the collection of bacteria that we have in our bodies. When people think about bacteria in most cases they they think about pathogens, things that are bad for you. The microbiome is not that. The microbiome is the bacteria [that are] doing things for us. So for instance, many of the bacteria that we have in the gut are in charge of digesting nutrients. … They extract energy from nutrients. They break down fiber and they produce certain vitamins that our own body cannot produce. So the microbiome is this collection of bacterial organisms that [are] really important for our well-being.
How many different types of bacteria are there in the microbiome?
I would say in a person here in the US you can expect to find hundred to a thousand different bacteria depending on how you define a bacterial species. Right. All of us have, for example, a bacteria that you’re probably aware of: E. coli. Right. All of us have E. coli, but your E. coli is different to my E. Coli. So these organisms change very quickly. They acquire mutations very quickly. And so even though we have the same species it is not exactly the same. So my E. coli might be very good at doing certain things that yours is not or the other way around. So I always tell people it is difficult to give a precise number because it is difficult to count.
What are the differences between the microbiomes of healthy people and the microbiomes of people with inflammatory bowel disease?
In patients with IBD the microbiome tends to be much less diverse. And this goes back to this idea of an impoverished ecosystem: we have less species and because we have less species it is a more fragile environment… So I think one of the things that we are we are finding repeatedly is that we are missing species that are able to produce certain compounds that have anti-inflammatory properties.
How would a fecal transplant work for someone with IBD?
The idea is that we’re going to replace the microbes of a patient with the microbes from somebody else from a healthy donor. It’s conceptually similar to an organ transplant … So basically the way a fecal transplant works is you screen a pool of donors so they have to pass certain criteria—they cannot have infectious diseases of any kind and they cannot have had antibiotics for a number of months. You’re putting microbes from a person into another person, [so] you want to make sure that you’re not passing something that can cause harm to the patient. And then the procedure is relatively simple—you obtain feces from the donor. You mix them and then you filter that mixture and you transplant that mixture into the patient through a colonoscopy.
Want to learn more about fecal transplants, like how effective they are and what other diseases and problems they might be used for in the future? Wondering if you should take probiotics? Listen to the episode for much more.