Science Friday - How Gut Microbes Are Linked To Stress Resilience

Episode Date: October 9, 2024

The phrase “go with your gut” is often used to say one should follow their intuition in the face of a big decision. Recent research in the journal Nature Mental Health shows the gut really could have a big impact on mental health and decision-making.This study shows a clear link between people who handle stressful situations well and certain biological signatures in their microbiomes. Certain metabolites and gene activity in study participants were associated with high emotional regulation and cognition. These more resilient participants also had reduced inflammation and improved gut barrier integrity.The study builds on previous research that shows the brain and the gut are closely linked, and that a dysregulation in one can lead to a dysregulation in the other. Lead author Dr. Arpana Church, co-director of UCLA’s Microbiome Center and associate professor of medicine, joins Ira to talk about the study. They also discuss how probiotics could someday be a promising treatment for mental health conditions.Transcripts for each segment will be available after the show airs on sciencefriday.com. Subscribe to this podcast. Plus, to stay updated on all things science, sign up for Science Friday's newsletters.

Stress is linked to all sorts of poor health outcomes, from our brains all the way to our guts. If you think about stress, it's almost equal to smoking five cigarettes per day. It's Wednesday, October 9, better known as Science Friday. I'm SciFRI producer Kathleen Davis. There's a growing body of research that connects what happens in our gut to what happens in our brain. And recent research shows another clear distinction. people resilient to stress have different microbiomes than their more stressed out counterparts. Knowing this information could change the way that we treat stress into the future.

Here's Irafledo. Joining me to talk about this work published in the journal Nature Mental Health is the lead author of the study. Dr. Arpna Church, co-director of UCLA's Goodman-Luscan Microbiome Center based in Los Angeles. Dr. Church, welcome to Science Friday. Oh, thank you for having me on here. How did you get involved in this? So I was actually, you know, my path to poop was actually from the top versus, you know, top down versus bottom up.

Very nice. Very nicely put. So I am actually a psychologist with neuroscience expertise. And I started in the psychology world. And when I came to UCLA, started working in the division of digested diseases. just realizing like, you know, we're just so interconnected. As a medical field, we are so siloed and we tend to, you know, for example, if you have a cardiac condition, you go to cardiologist, if you have a lung condition, you go to pulmonologists,

which just so siloed. But that's not the way everything works. And as I said, I started from, you know, the brain down and realizing that that brain was this, you know, computer system, this hard drive that controlled all these other organs. really was how it started. And then looking at how everything is interconnected. And then being a psychologist, you know, realizing like, you know, when people started to talk about mental health and started to, you know, use phrases like,

oh, you know, I feel sick to my stomach, my head hurts. And just realizing, like, how everything was just interconnected. And so it just seemed like a natural path for me to look at the whole body as a system. and I don't just only look at the whole body as a system, but I also look at the environment because, you know, fortunately and unfortunately, we don't live in bubbles where we're interconnected to each other, we're connected to, you know, what's happening in our environment.

And that's why I kind of got into this. Let's talk about what you found in the study. Tell us. Sure. So, I mean, it's, I think it's important, first of all, for us to talk about stress. When you think about stress, it's an inevitable part of life. So studying how we handle stress can really help us understand how to prevent developing diseases.

Now, if you think about it, 77% of Americans report physical symptoms caused by stress. Right. And 33% of Americans report that they're living with extreme stress. So that accounts for over $300 billion that are lost annually in stress-related health care costs or even missed work. And if you think about it, stress is linked to the onset and progression of disease. It can be mental health illnesses,

like anxiety, depression, or even physical health, like issues like obesity, irritable bowel syndrome, cardiovascular disease. In fact, if you think about stress, it's almost equal to smoking five cigarettes per day. Is that right? Yeah.

And also think about stress. It's not just when you're an adult, It can happen in any form. It can happen any point in your, you know, in the lifespan from infant to adulthood. Like think about a child that's left in the crib crying. That's stressful. Think about kids going to school. That's stressful.

Making friends being bullied. That's all stressful. And then you're an adult, economic hardships. And then all the way into old age, you know, you lose a loved one, death of a spouse or a family member. So stress is just part of our life. It's inevitable. So for this study, that's what really was the impetus of looking at the study. I really wanted to know what it was about stress.

And why is it? Because we all experienced stress, right? Every one of us in some form or another experience of stress. So why is it that some people who experience stress do really poorly? And what is it about those resilient individuals, those individuals who have like this grit? what is it about them that who despite experiencing stress are really highly resilient? And so that really was the question. And honestly, in medicine and in research, we're always looking at the negative.

We're always looking at disease. So I really wanted to flip the script and say like, okay, what is it about the people that do really well? How about studying those individuals? Yeah. And maybe that might give us some insight. And you went by looking into people's guts to find the answer. We actually, we did a lot of things.

So we had 116 adult individuals, and we gave them a whole bunch of questionnaires and physical and psychological exams. So we measured things like anxiety, depression. We also measured resilience. And the way we measured resilience was using something known as. the Connor Davidson Resilience Scale, which is basically the 10 items scale that measures things like positive acceptance of change, tolerance of negative affect, tenacity,

the ability to recover after stressful events. And there are really five factors of resilience. You know, one is personal competence, trust in one's instincts, positive acceptance of change, sense of control, spiritual influences. And we also,

also measured cognitive functioning. Then we also put them in the MRI scanner and we basically looked at not only their brain structure, but also the connectivity of different brain regions. So like how one brain region is connected to another. And then we collected their stool in order to look at their microbiome abundance and function. That was a great windup. Here's the pitch. What did you find that was different in one person or one kinds of stress handler than another? Yeah, so the highly resilient individuals, the ones that did really well with stress, if you looked at the brain,

we found that there were brain features or brain signatures, features and functions that were related to improved emotional regulation and cognition. So what that means is, if you think about the brakes in your car, right? if you tap the brakes a little bit, your car stops. Great working brakes. But if you're, you know, in a near car collision and your brakes are not working that well

and you're jamming down your brakes and you're pressing really hard, that basically shows that those brakes are not working that great. So that's the same thing. So those cognitive, those control regions of the brain were working really well. They were able to modulate like these emotional or these hyper, arousal regions in the brain. And then we also saw that at the gut level, there were these metabolites and these transcriptomes that were linked to reduced inflammation and also were related to better gut barrier integrity. We also saw that these individuals were very extroverted. They were very

mindful. And this was really interesting. I was blown away with this. But they were also kinder. non-judgmental. We could all use some of that now. Oh, my God. Like, you know, I mean, it really, it says something. I talk about this. Like, just being very easygoing and grateful and accepting really means something. So maybe not being that reactive or, oh, my God, I can't believe somebody did that to me.

Or, you know, maybe just like, okay. Yeah. Well, my question is that is the chicken or the egg? I mean, are they kinder because of what? what's going on in their guts? Or is that influenced the other way? People always ask this question, whether they're talking about whether it's the brain that's messed up

or if it's the microbiome that's messed up or is it our personalities at need adjusting, who knows? You know, this chicken and egg question always comes up in science. And to be honest, like, we don't really know whether it's the chicken or an egg. And I like to say, does it really matter? The important thing to remember is that because everything is connected, we can stop the cycle and we can influence because if you think about it, everything is connected.

It's bi-directional. It's like the cyclical loop. So what I like to say, like, who cares what comes first or after? The point is that we can break the cycle and intervene and change things. That's what we really need to be asking is, can we change it? and how can we change it? Well, that's, you anticipated my next exact question. Can we change it?

And how can we change it? I mean, from what you've learned in your study, you found biological markers, you found regions in the brain that act differently, regions in the gut that act differently. How do you use that knowledge? You know, it's very exciting because your brain is very malleable.

Your microbiome is very malleable. And guess what? Even your personality is very malleable. So I love this kind of integrated what I call whole person or systems biology work because it shows that we can come up with these multimodal, these multi-pronged interventions that are designed to provide targeted support, whether we're talking about at the brain level. So it could be more resilience training.

It could be stress reduction. But even at the behavioral level, think about like, okay, maybe teaching people to be more grateful, more easygoing, getting along with people, not being more extroverted, maybe not being so as neurotic, you know, just those kinds of things, being more mindful and non-judgmental. And then at the microbiome level, you know, people always talk about, oh, my God, how can I change my microbiome? And I always tell people, guess what, the microbiome is the easiest thing to change. you can do things today that will change your microbiome within 24 hours, even by tomorrow. So I know when people think about changing the microbiome, they talk about like, oh, you know, fecal microbiome transplants or taking capsules. And I'm like, oh, you know, let's not even go there. Let's just talk about easy things, things that we know that work.

So you can, you know, we can talk about probiotics or prebiotics that can change your microbiome, but even something easier than that, your diet. It's the most accessible, easiest things to change your diet. And I like to tell people, think about when you're stressed. You know, some of us, you know, either eat a lot and we tend to go for those high calorie foods or some of us, you know, just don't eat. Like, you know, we go into this kind of like I don't feel like eating them too stressed. Right, right.

But really just targeting your diet and eating a healthy diet, a diet that's a balance, that's diverse, that's rich in fiber fermented foods, I think that that's the easiest way to do it. And I always talk about eating diets rich and diverse fruits and vegetables, and I call them ABCs, always be counting. And I don't mean counting calories. I mean counting at least 30 different vegetables and fruits per week. Wow.

It will really help maintain your healthy microbiome. If there's anything that you take away from today, take that away. ABCs, always be counting. 30 different fruits and vegetables per week. Wow, that's not the American diet, but I want to. You know what, but people always say that that's so hard. How can I do 30? Oh, my God.

I can't do that. You're crazy. I have a hard time just getting, you know, two vegetables per week. And I tell people, it's really easy once you start counting. Let me give you an example. If you end up having a bowl of soup or a bowl of stew, think about what you're putting in that stew, right? you're putting tomatoes, onions, garlic, maybe some kind of herb, maybe some kind of spice like turmeric or, you know, pepper. That's already five or six right there. You add some carrots.

Maybe that's seven. That's seven already in one meal. So 30 per week, that's easy. Wow. You know, you mentioned a term very quickly that I have to go back. I have to replay the tape in my mind. You talked about when we were talking about changing your gut health, and you talked about probiotics and crapsules. Crapules. I think I know what that is, but you have to tell me. Oh, it's just a made-up word. So, you know, I love it. So there's something known as fecal microbiome transplant where you're basically taking the microbiome of somebody else and you're ingesting it, whether you're ingesting it through a capsule, you know, there have been stories of people like making milkshakes.

I mean, this I know is disgusting. But people have talked about making, you know, milk shakes and having it that way or even, you know, like put it up through your colon. So those are ways that you can have these microbial transplants. But, you know, if you've heard stories of people who have tried to do these kinds of things, it's not only, first of all, it's not regulated. It's very risky. It would be very complicated.

But secondly, whatever that other person has, you will end up getting that. So you might end up treating one thing, but then you might end up getting, you know, for example, like, say for example, I decided to take my husband's poop and somehow ingested, whether it's through a capsule or whatever. If he has acne, I will end up getting acne. No. If he has depression, I will end up getting acne. I will end up getting depression. So it's really very complicated. Yes, unintended consequences.

Yes, unintended consequences. And it's not regulated and it's just very complicated. So I really, I really think they're crap. They're crapsules. I really don't advise. So you don't recommend a fecal microbiome transplant. From the stress resilient people into people who might need it because there's unintended consequences.

of that. I don't think the research is there. I think if we really need to be doing more research, maybe we need to be doing more research on creating, you know, targeted probiotics or even prebiotics or symbiotics. So, for example, like we could take the microbial markers from this study, looking at the bacteria or the metabolites that are impacted and creating a supplement from that and then testing that. Right.

to see if that works. That to me is safer. It's, it's, you know, it's more regulated. Is that on, is that on the horizon, you think, to do that? You know, this is where the whole, you know, motive at the Goodman Luskin Microbiome Center is, is to be able to develop these targeted, either brain or gut microbiome targeted treatments. That's the whole point of the center is that we, we do these large studies and we find these signatures and then, okay, so people are then, okay, now what? What, okay, fine, great, you found this signature. How does this help me?

Sure, we can give them, you know, interim solutions like, hey, you know, maybe change our diet. But I think these kind of tested and engineered supplements are definitely on the horizon. In fact, we have one clinical trial that we're doing right now based upon a patent. probiotic blend that actually came out of a study from the lab. Interesting. I mean, I hear you saying that we are really so connected to our poop, aren't we? Yeah, more than people realize. Yes. Well, there you have it. This has been highly fascinating, Dr. Church. This is, I think I'm certainly a better person for learning about poop and the microbiome and all the things you brought with you

to share with us today. Thank you for taking time to be with us today. Thank you for having me. Dr. Arpena Church, co-director of UCLA's Goodman-Luskin Microbiome Center based in Los Angeles. And that's all the time that we have for now. A lot of folks helped make the show happen, including... Danielle Johnson. Jason Rosenberg. Dee Petersmith. Full of Samares.

And many more. Tomorrow, looking ahead to the elections and the science of interpreting and influencing voter behavior. But for now, I'm sci-fri producer Kathleen Davis. Thanks for listening.