We've recorded a series of podcasts on the microbiome and its wide ranging impacts. But boy is this a field that moves rapidly. As soon as you think you've covered much of the territory, along comes some new and exciting findings, and this is the case today. We're going to describe research done by our guest, Dr. Ibrahim Javed. He has done innovative work on links between the gut microbiome and the brain, particularly focused on Alzheimer's disease. Dr. Javed is an Enterprise Fellow and National Health and Medicine Research Council Emerging Leadership Fellow in Clinical and Health Sciences at the University of South Australia. Interview Transcript So let's begin, if you wouldn't mind, with an explanation from you about what the gut brain axis is and tell us how it's important. Yep. Now we see a lot of, a lot of researchers around the globe building on investigations around the gut brain axis. But if we, if we investigate what this gut brain axis actually is, It's kind of like a bi-directional communication between two organs in our body, the gut and the brain. And when we particularly talk about gut, we have our stomach and our different portions of the intestine. What we're actually interested in is the microbiome and all those small little things living inside the gut. There are around 100 trillion microbes in the gut, which is three times more than the number of cells in our body. So, we are kind of like more microbes than, than human cells. And they communicate with different organs in our body and how they communicate with the brain that we can describe it as a, as a gut brain axis. And then this whole gut brain axis thing was somehow kind of invisible to us. We were just looking at it as a fecal material or waste coming out of our body. But now we see a lot of importance to these gut microbes. They help us in a lot of daily things that we do. They shape our behavior, our response to stress, our immune system, and then how we respond to different medicines, and how we do our daily tasks. So, they have a lot of roles in that. They help us digest food, that's their main obvious function. But now we are more. getting more and more information about them, that how they are integrated with a lot of different things in our body. So, kind of like they are partners in our life. That's a very, very nice explanation. Can you tell us about the importance of microbial diversity? Yep. So microbial diversity, we can, we can refer to, to as a composition of all those bacteria, viruses, and fungi to some extent that, that live in, in our body. Digestive track and, and in a lot of other animals as well. And this diversity is very crucial in maintaining the gut health and on overall well-being of, of humans. And, and this microbiome whole thing is like, it is obviously associated with a lot of health benefits and, and how we develop disease, but it's also right from the beginning of life they help us in developing our brains. They help us mature the brain system and the immune system. Obviously, they help us in digesting food. So, generally, we can actually divide them in two portions. One, we can call them a good gut bacterium. They help us with all these things. And then they are bad gut bacteria, which are kind of like kept within a within a bay. They are kept under control by this good gut bacteria with the help of the rest of our body. And in somehow in some conditions with the age or with the dietary habits or environmental factor or lifestyle, if they overcome and, and they take over the control in the gut, that's where the thing starts going haywire. When I was growing up, microbes were a bad thing. You didn't want to have microbes. And now, now we hear that there are good microbes and now you're talking about the balance. There are still bad ones, but good ones. And the balance of those two was a really important thing. Let's talk about how bad bacteria find their way to the brain. How do they get access? So, as we discussed, they are kept within the bay or kept under control by good bacteria and also by other different immune systems in the body. We have different checkpoints, like we have different barriers or three different compartments, the gut and the blood and the brain. And we have barriers that separate out these compartments and these barriers are very tightly controlled, very good health cells tightly integrated with each other and they police that whole things what need to go across and what does not need to go across what we need to stop it within that compartment. If we have adverse environmental factors, or poor dietary habits and these bad gut bacteria overcome, they produce a lot of different molecules to communicate with each other. And they produce a lot of different molecules to take over the good bacteria. And these molecules, they can get across those barriers, and specifically if they can get into the brain (that's what we are researching), they can do a lot of different bad things ...
