Alice in Futureland

Some think that consciousness exists in those gaps between thoughts. But what about spaces between tangible things—what lurks in those shadows?

Information through time revealing elusive memories wakes us up to what we’ve known all along.

Taste shapes, hear colors, feel patterns, envision sound coupling and uncoupling…sensing mind, body, feeling and outer reality.

Evoking the introspective nature of our sense of self; sensing qualia, the instances of our subjective, conscious experience.

Engaging with more than 53 senses in which we experience the world…

Evoking free will and the ‘noise’ that sometimes disrupts or challenges our freedom—in-between moments of static—and if we continue in our belief, we come out of the noise free again.

ALICE: When you think of microbiome, you probably think gut health. But there is new research into the many roles that gut and skin microbes play, including what is called “a glow of health.”

DR. SUSAN ERDMAN: We envision ourselves swimming in a sea of microbes. There are millions, billions of microbes living inside of us, living on the outside of us, living everywhere around us.

ALICE: We’re speaking with Dr. Susan Erdman, a Principal Research Scientist, and Assistant Director, in the Division of Comparative Medicine at MIT, whose research looks at how bacteria and inflammation contribute to systemic health and diseases.

DR. SUSAN ERDMAN: And those microbes are an important part of who we are. They influence how we're responding to the environment. They're influencing things about the quality of our skin, the quality of the membranes in our mouths and around our teeth. When you swallow and things go into your intestinal tract, that mucosa—that membrane that's part of your intestine—that membrane is influenced by the microbes around us.

ALICE: Part of Dr. Erdman’s research is looking at what is called “the big axis.” She's working to understand how the body interacts with the external environment—and the role of microbes in the immune, brain and skin connection.  

DR. SUSAN ERDMAN: We're very, very interested in how a body interacts with the external environment. And a lot of the ways that the body interfaces with the environment involve things that we've taken into the body and then get passed through the body. Our body has multiple ways of interacting with that content that it's exposed to on the outside, and exposed to on the inside. And a big part of that is the immune system. The subtleties of having an immune system that can differentiate between things that are a threat and things that are tolerable to the body are the kinds of subtleties that are the very hard work of the immune system. In a human, these things are very sophisticated. And trying to understand those processes and how the body can manage food, outside contaminants, and so forth—the microbes that are an important part of breaking down food in the gut—and manage to reconcile all of that in a way that it doesn't inflame itself to death is a big challenge for the immune system. So the immune system is really a huge friend to us. And when the immune system goes awry—think autoimmune diseases—it can do very, very destructive things. We became really, really interested in the immune system, and how the immune system can begin to keep us healthy.

ALICE: The immune system doesn’t operate on its own. It networks with the brain, the gut and even our largest organ, the skin to create a big axis. That axis not only protects you, but enables meaningful interactions with the environment. Interactions that can give you a sense of joy or compassion.

DR. SUSAN ERDMAN: The immune system doesn't direct everything about our body, though. A lot of what is directed by our body is in our brain, and how our brain is processing the interface with the outside environment. We became very, very interested in whether or not those things that the immune system is doing on internal surfaces, like the gut, in terms of trying to manage the activities of the microbes that have to digest the food—the food that's coming in from the outside—and the interactions of the immune system with all of that. We were very interested in those activities and the brain, and that big picture axis between the brain and the activities of managing the immune system with the external interface of the environment, which could be inside the body in the gut or on the outside with the skin—we hypothesized that those are the most interesting activities for our potential to be as effective in our interactions with the environment as we can possibly be, for things that derive a sense of joy and purpose in our living, that help us unify our activities beyond ourselves with other members of our group—to extend even to empathy, compassion, caring for others.

ALICE: And it turns out, microbes are a critical part of the big axis!

DR. SUSAN ERDMAN: We hypothesized all of these things were driven by how effectively our bodies were managing these relationships between the microbes, the immune system, and the brain—that this axis that is part of a fundamental part of who we are that could be traced to similarities—even with a species of animals that are so simple—types of worms—that are so simple that, literally, they are a tube. All they have is their external and internal environment and processing—that those kinds of networks inform fundamentally big decisions about what we're doing with our world, how we're caring for others in the community, and so forth. Our research, then, is summarized, or boiled down to, trying to pick apart these relationships. How could we tweak the microbes? How could we tweak the immune system? How could we tweak those relationships with the brain, and the connections between the brain and the gut, or the brain and the skin, for our ultimate benefit? That's the nature of our research.

ALICE: Don’t fear those microbes on your skin, they are important for how you look and how you feel. Some microbes on your skin can impart what Dr. Erdman calls “a glow of health.”

DR. SUSAN ERDMAN: When we think about how our bodies are interacting with the environment, an important part of that interaction is the character of all of what they call epithelial surfaces. So that's the skin. And so in a very simple, mechanical way, how the microbes interface with our bodies is influenced by the health of our skin, and the mucous membranes within our body. And really, in the bigger picture, they're sort of all one and the same. We became very, very interested in the idea that when a baby is first born, and is very naive—comes into the environment with almost no protections—that those microbes that are the very first microbes to begin to colonize an infant after it's born are very important in how the future relationships with the outside environment will happen, even extending to decisions that those infants might make—decisions in their brains—and then the character that they evolve over their lifetimes as they become adults. And we had a hypothesis that these first microbes are very, very meaningful in establishing those connections. And it has some very tangible, very outwardly visible, benefits associated with it. And one of those benefits is that some of the microbiota that are common to an environment that connects with breast milk and the feeding of breast milk—or alternatively, fed by the proteins of milk—are the kinds of microbes that help make a skin surface healthy, resilient to outside damage, and so forth. So our simplistic way of thinking about this was, wow, the mom is giving the baby the nutrients to feed microbes—and sometimes actually giving the baby the microbes themselves—that are helping that infant develop a healthy skin that will protect it from the outside environment.

ALICE: Dr. Erdman found that taking the first microbes you get from mom at birth and putting them in an adult could stimulate healthy skin.

DR. SUSAN ERDMAN: The glow of health series of experiments demonstrated that you can take some of these microbes that come from this mother-infant niche—the microbes that a baby might acquire from its mom, or would get nurtured in those first couple of weeks of living—and that those microbes in an adult might be able to impart the same healthy infant skin effects in an adult that they would in a—than in a newborn baby. And what we found was absolutely amazing—that these microbes stimulate the immune system—and even some hormones, in the brain and locally—that help them make the skin very, very healthy.

ALICE: Dr. Erdman also found that these same microbes could help with rapid wound healing on your skin. Imagine a microbial topical that could one day replace stitches!

DR. SUSAN ERDMAN: But there's so much about a healthy skin that's important to a body in the short term and the long term—how the body functions as a whole. So, for example, we focused on wound repair. We focused on wound repair because we were really interested in the possibility of wound repair serving as a surrogate for being healthy, and living a long, healthy life. So if you imagine a time scale where you have an injury, and that injury repairs very, very quickly—we'll talk about the outside skin for the moment. So, you make a little tiny defect in the outside skin, and it heals really quickly. So really healthy skin is a very important part of staying healthy over a lifetime. And so we went straight for that axis, and started to study what it is that would keep skin that healthy. And we found, through a series of experimental models that allow us to define these things—either things in a Petri dish or, say, mouse models that would allow us to look at what happens when we feed this microbe, and how healthy do these mice stay across a lifetime, and are those things translatable to the next generation, perhaps? And so we became very, very interested in this possibility that this was a key—this healthy, glowing skin, the glow of health—was a key to understanding our bodies and our well-being in the environment in the bigger picture of things.

ALICE: One bigger picture Dr. Erdman discovered is the link between healthy skin and reproductive fitness.

DR. SUSAN ERDMAN: And so we had done a series of experiments in a mouse model system where everything about the mice was exactly the same, except that we added the microbes to the drinking water. And we found some really shocking things. And one of them was that the outer skin coat of the mice—what we refer to as the glow of health—is actually a display of reproductive fitness. That—not surprisingly, that reproductive fitness element was later shown in another series of studies that we nicknamed "Great Balls of Fire." And in that series of studies, what it showed was that this skin health—this really smooth, sleek, shiny, fur coat in the mice—was actually substantiated by these different reproductive criteria. So, the females had bigger litters of babies. They had more interest in caring for their babies, and raising their babies to adulthood. The males had what we call mouse swagger. So those manifestations—that really shiny fur coat was because the skin had changed in a way that you could see under a microscope. And it only took about five days after we started feeding the microbes to the mice to be able to see these changes. So if you took a section of the mouse skin from the mice that were eating the probiotic bacteria, and you took a section of the mouse skin from their counterparts that were treated exactly the same way, that came from the same parents, everything was exactly the same about them, except that they had regular drinking water without the little probiotic boost—the difference of those tissues under the microscope, when you stained them, sectioned them, looked at them histologically with a microscope—the differences were really dramatic. Those differences were a thicker, healthier skin. And the oil glands that produce the oils—the hygienic oils, the oils that help keep skin healthy, and help cultivate other healthy communities of microbes—they were actually changed in a really short period of time after those mice started eating the bacteria. And so there were all of these interesting connections that all went back to how the immune system worked, and how these hormones worked, that all of these things were communicating throughout the body based on simply feeding a single microbe.

ALICE: Are you thinking what I’m thinking? Imagine a probiotic that makes your skin healthier and you more fertile. But there’s more… Dr. Erdman found that the same microbe can actually make you slender.

DR. SUSAN ERDMAN: And so what we had identified was an axis with a microbe, the immune system, and the brain, using a mouse model that allowed us to take this down to the most basic levels of scientific discovery, that opened the door for enormous potential for humans to be able to benefit from those same kinds of things. So, if you were to look at a cage of the mice that were drinking the probiotic microbe, and look at a cage of mice that were matched in every other way but just had regular drinking water, you would discover more than just the super-sleek, shiny, healthy-looking fur coat and skin in the probiotic-treated mice. You would also notice that they were more slender and that they had a more positive, exploratory attitude within their cage. And so, what we found was that abdominal fat, in particular, was reduced in the mice that were—the quantity of abdominal fat, if you were to weigh it or to measure the size of it, was reduced in the mice that had gotten the probiotic. And this was true in both males and females. And the character of that fat was completely different. So, the character of the fat had fewer inflammatory cells, fewer of the cells that create the factors and drive a chronic, smoldering inflammation that is so bad for the body. That—all of that—was decreased in the mice that got the probiotic. So, the underpinnings—this idea that these depots of body fat—unhealthy body fat, inflamed body fat—create this engine of inflammation that makes the heart less healthy, that makes muscle mass decreased, that makes sexual interest drop. All of that stuff was reduced in the mice that had gotten the probiotic. So, the counterpart product was the probiotic-fed mice were slender, they were interested in sexy things, and they had this fabulous, glowing fur and skin.

ALICE: Probiotics are usually a special blend of microbes which work to balance or interact with the different colonies of microbes that live inside and outside of the body. Could the probiotic that Dr. Erdman is researching potentially have the same effect on everyone?

DR. SUSAN ERDMAN: One question embedded in this is not just, is there one super microbe, but does that microbe have the potential to change you, and change things about your skin, or your swagger, or your slender waistline, in spite of recognizing that everybody is carrying a completely different group of microbes with them? So, any of you have microbes that are so unique in their balance and are changing in different ways with each new thing you eat—what you eat for breakfast, what you eat for lunch, what you eat for dinner—it's all incredibly complicated. One of the super-interesting discoveries that we made going through all of this was that this single microbe alone—just adding this one microbe to the mice—had the power to change them, almost irrespective of which other microbes they currently had on board. We were really not expecting that.

ALICE: Wow. I can’t wait for that super microbe to be available. Thanks Dr. Erdman for sharing the new possibilities we are discovering about our powerful microbial partners.

That’s it for this mad tea party. Please check out our other podcast with Dr. Erdman on microbes, oxytocin and love—yes, you heard that right! Check out our weekly newsletter Alice in Futureland on Substack, and our book “Thriving with Microbes.”  And until next time… keep wondering.

ALICE: I’m continually fascinated with the world of microbes, and how the trillion microbes that live on and within us shape what makes us human. Our guest Dr. Susan Erdman and her research team at MIT have discovered amazing links between a single microbe that can influence our sense of bonding, identity, purpose... and love.

DR. SUSAN ERDMAN: I've always been a person who's interested in how the world works, and the bigger picture of things. Even as a child, I remember being curious about even things like how we know everybody is seeing the same color when they hear the word "green." And with the-always with the idea of understanding our environment and ourselves, in a way that we could create a more balanced whole.

ALICE: Dr. Susan Erdman is a Principal Research Scientist, and Assistant Director, in the Division of Comparative Medicine at MIT. Her research is funded by DoD and NIH grants. She is Board Certified in Comparative Medicine (A.C.L.A.M.), and studies how bacteria and inflammation contribute to systemic health and diseases... and how bacteria affect our hormones.

DR. SUSAN ERDMAN: A single microbe can be very powerful. This is not an intent to have one single microbe answer all questions, but rather, give us a direction, give us motivation to continue unraveling the mysteries of how microbes interact with our bodies as a whole-particularly with these players of our best friends, the immune system. And then optimizing how our brain-our master control for interfacing with the environment keeps us in a healthy frame of mind, keeps us focused on positive things-even extending to positive social relationships and the benefits of caring for others, in the same ways that ultimately mimic how a mother is intensely interested in taking care of her baby, and making a healthy world for that baby.

That same concept, we hypothesize, can be extrapolated to a society as a whole, and that more of these microbes that boost these hormones that make us care about others-want to take care of others-don't do it at the expense of taking care of ourselves. We still take care of ourselves. We have the capacity to reach outside of ourselves and take care of others, and try and make this a better world for all of us.

ALICE: Why do you suspect microbes may improve our relationship with ourselves, and others? And what was your ‘aha’ moment?

DR. SUSAN ERDMAN: This question about our identities, our sense of purpose, our desire to care about more than ourselves for the greater good is probably one of the most riveting questions of human existence. And we set out to try and understand some of the scientific underpinnings of that exact question. When we started to investigate organisms that we thought would have the potential to help us really understand who we are and how we can stay healthy, we zeroed in on a human breast milk microbe, with the reasoning that these are the tools that a mother passes onto her infant. This is a survival kit for the future.

And what this survival kit does is it also helps Mom. It helps Mom because she's carrying these microbes. And because her hormonal environment is one that supports this passing along the survival kit to her developing infant, she also is connected, in a very deep kind of way, to this microbial connection. We decided to scientifically mine-to dig deeply into the scientific underpinnings of this connection-to help us understand how this survival kit might be a clue as to what mammals have the potential to become.

ALICE: Dr. Erdman’s research looked deeper at the connections this microbe makes, and found it is a powerful player in the role of bonding.

DR. SUSAN ERDMAN: Most powerful among those things in the mother-infant bond is a social bonding hormone called oxytocin.

Oxytocin causes muscle contractions in the uterus that introduce the infant to the world. The infant is bathed in a sea of oxytocin at the time of birth, and begins to develop neurological connections, and also gut microbial connections based on relationships with this hormone, oxytocin. But one of the most powerful things, which is well-substantiated by animal models systems, is that oxytocin is really important in a mother having a desire to take care of her infant. And this, in the most simplistic way, is kind of earth-shattering. So earlier, Alice asked, did you have an aha moment? This is about as close to an aha moment as what we've had in our entire scientific journey. Because realizing that this microbe fills this niche with this mother-infant bond was what led us to explore the possibility that this microbe might actually be interfacing with this hormone oxytocin.

ALICE: Wow. So, a single microbe within us may be what induces our love hormone oxytocin? And it starts at birth?

DR. SUSAN ERDMAN: In mouse models, and in other animal model systems, it becomes very obvious that not only is the oxytocin important in actually the contractions of giving birth and the contractions of supplying that breast milk-which are key to a mammal being able to interface with the environment and get their offspring started on this trajectory of life-these life-giving events, the very essence of the mother caring for her infant, also requires oxytocin.

So, animal model systems that are completely missing oxytocin are capable of producing milk. They're sometimes capable of giving birth, although not very efficiently, because they don't have the hormone to give birth. The mothers have zero interest in actually taking care of their babies in the absence of this hormone oxytocin. That's how important it is for everything about the mother-infant bond. In the absence of this hormone, there are other hormones that might step in to help kind of try and patch things together, as part of feedback loops. But oxytocin is the master controller when it comes to a mother's interest in taking care of her infant.

So, this is the lightbulb moment. This is flash, flash, flash. If a mom is going to take care of her baby, she has to have this hormone. If this microbe is facilitating the production of this hormone, we have discovered something incredibly fundamental about what it takes for life-what it takes to build a life, to keep a life, and then to create a very interesting, selfish microbe who actually is invested in the social existence of mammals.

ALICE: It turns out that our microbial passengers are invested in our survival, and perhaps, making us social. Could the future be bioengineering love microbes?

DR. SUSAN ERDMAN: Are they actually helping us be a social being? Are they actually helping us want to take care of our-the next generation? This was the question that we went after. And we were completely shocked when we hit the jackpot, and found out that this microbe, when it's separated from that system and given to an adult animal, is actually capable of boosting the levels of the hormone oxytocin within the brain, and within all of the tissues of the body of the lucky individuals that are carrying this organism.

This particular concept, this idea that you could separate this microbe out and you could cause oxytocin to increase gives us clues to social networks that are previously uncharted. So, what do we have? We have a microbe that boosts a hormone that isn't just important in how a mother takes care of her infant, her interest in nurturing that infant.

Basic scientific studies looking at how important family nurturing of offspring is, in order for that individual to be a good, contributing, healthy, happy member of society in the future-whether it's an animal model system, or it's a person-that psychology science is very well-established.

But just as amazing is the potential you could take that microbe out of that system and separate it, and put it into an adult, and change that adult's interest in taking care of others.

ALICE: Could manipulating this microbe change the axis of caring in an individual? In a society? Could a single microbe be the key to survival of the kindest?

DR. SUSAN ERDMAN: So, let's play with that concept for a moment and say this is a hormone that, in human subjects, has been connected with expressions of empathy, expressions of altruism, and expressions of enjoyment of spirituality-the concept of belonging to a greater whole. That doesn't mean traditional religions, necessarily. It means the common threads of humans having a meaningful, spiritual experience that makes us belong to something, that makes us part of a larger whole, and makes us care about that larger whole to the same extent that we care about ourselves, maybe even more than we care about ourselves as an individual.

And that concept, that sort of thing that humans have searched for, that idea of what would make us care about-what would make us altruistic? What would make us care about some individual that's not even clearly related to us? Why would we possibly care about their survival? We care about their survival because these microbes are manipulating an axis within our brains that is giving us the capacity to return back to a primal, larger whole-that the survival of that whole is ultimately what drives the ultimate benefit of the survival of each of us as individuals. And these holistic relationships-this holobiont, these microbes that we carry with us-sometimes the microbes that we've dismissed over time, because our practices are not so natural as they used to be, our diets are not so natural, our birthing processes are not so natural, we use antibiotics to counteract bad microbes-this ends up changing elements of those microbial underpinnings, these very fundamental relationships that drive our potential with human existence. We have the opportunity, by understanding this process, to get the benefits of how antibiotics might help us counteract bad bacteria, how giving birth within a hospital and under certain conditions might help us eliminate deadly diseases-we can still get the benefits of all of those things, and still have the potential to understand how to make us the best human beings and human experience that we can possibly have, in the larger picture of things. And we see those connections in a very fundamental way, with scientific underpinnings between microbes, how the immune system works, and hormones that have far-reaching potential. And oxytocin is not the only hormone that's modulated by this microbe, but in ways that has the potential to change who we can become as a society, how much we care about others, and our interest in caring for others to the same extent that we care for ourselves-that potential exists with a key, through a hormone like oxytocin.

ALICE: Thank you, Dr. Susan Erdman, for explaining the amazing connection of microbes and the love hormone oxytocin and its role in bonding, empathy, altruism and yes, survival of the kindest. Imagine when we can bottle that microbe! Are you thinking, like me, love-biotics? Sign me up!

That’s it for this mad tea party. Stay tuned for more microbial wonders with Dr. Erdman. Check out our weekly newsletter Alice in Futureland on Substack, and our book “Thriving with Microbes.” And until next time... keep wondering.