Q&A with Cathy Lozupone, Scientist Defining the Human Belly
For the past eight years, Cathy Lozupone has been up to her stomach in bacteria.
Lozupone, who is in the fourth year of her post-doctorate, analyzes DNA sequences at the Knight Lab at the University of Colorado Boulder, specifically focusing on the “ecosystem,” or microbiome, of the human gut. The Knight Lab and Lozupone conduct research at the forefront of human gut health. The lab has collaborated with anthropologists on the Human Food Project, which explores contemporary disease through analysis of the gut’s evolution in the past.
The human gut has become of interest in light of the recent health craze. Scientists are trying to identify what a human gut looks like today as well as what it consisted of in hunter and gatherers. Much research points to the fact that the gut plays a more integral role in human health than people realize.
Lozupone spoke with the Boulder Stand about the Knight Lab, what the human gut microbiome is and the specifics of her research.
What is the gut microbiome?
The gut microbiome is this group of microorganisms that live in the human intestinal tract. We know the most about what this looks like across cultures, across people and in different diseases by looking at fecal samples because those are the easiest to obtain. But when you look at fecal samples you only get what’s coming out at the end.
What role does the gut play in the health of the human body?
So one thing is digestion. When you eat it can help you digest the things that your body can’t – things like sugars. It also plays a role in immune system development. Right now, things like food allergies are on the rise. It’s believed that some of that might be caused by early life not being exposed to the right microbes that are supposed to train your immune system to tolerate certain things. With an allergy, your body’s reacting to something it should not be reacting to, so your immune system hasn’t been trained properly to tolerate something. Another thing is protecting against pathogens. When you knock them out with antibiotics these pathogens can more easily infect you. That’s called colonization resistance. It’s just that the healthy flora allows your body to resist the colonization of things that are bad for you.
What are you currently researching about the human gut microbiome?
One thing that we’ve sort of figured out is how little we know. The overall goal is to understand how (the microbiome) affects people’s health. But one of the first things that we realized we needed to understand before we could understand disease is, how does this community differ across healthy people? So that’s been one major focus of work done in the Knight Lab or with collaborators. Then, once you understand that, the next challenge is to understand, how does this healthy signature differ with disease?
That’s another thing, just trying to correlate the differences you see with differences in people’s lifestyle or just even genes – if someone has some sort of immune system differences that change those sort of bacteria. People eat a different diet so that changes the type of microbes that are there. Even just things we believe could have impact, like antibiotic use. You know, when you get sick and you take antibiotics, to what extent does that have a long term effect on the microbes? Can they just come back the way they were or are you actually doing damage that can’t be undone sometimes? So really just trying to understand all these different factors, how that relates to what’s there and then how these differences relate to disease and susceptibilities.
How is the human gut research beneficial?
Well, just having a greater understanding of what a healthy microbiome looks like can help to figure out ways to promote the maintenance of a healthy microbiome, whether it’s through diet or through limiting exposure to things that might be hurting them in the long term, like antibiotics. There are lots of different diseases that are linked to the gut, and hopefully understanding the gut could help treat those diseases. I think it’s the type of thing where there are lots of diseases that people never imagined might be linked to the gut, and now people are realizing that might be so. At the same time that we’re understanding that, we’re also understanding how broad the implications could be.
The Knight Lab is researching all of this at once?
I feel like the Knight Lab tries to tackle a lot in general. You do get involved often in lots of different aspects of this work at once. Of course you have to focus a little bit on things sometimes. But I do feel like having all these different things does give you this sort of global picture or make you able to sometimes figure out parallels that you might not have been able to if you were just sort of focused on one little question.