Director Suh Seong-bae,
IBS Center for Microbiome–Body–Brain
Physiology Research

Q1. Could you share your thoughts on the joint launch of the IBS Center for Microbiome–Body–Brain Physiology Research and the GIST Department of Integrative Neuroscience & Physiology?

It is a truly moving and momentous occasion for me. I believe that launching an IBS research center alongside a new department signifies the creation of a new center of excellence within GIST. It is particularly meaningful that we are embarking on this journey here in the Gwangju–Jeonnam region, rather than the Seoul metropolitan area. On a personal level, I am very pleased and grateful to have the opportunity to conduct research and contribute to the Honam region.

Q2. What do you believe led to the establishment of the IBS Center for Microbiome–Body–Brain Physiology Research?

The discussions with GIST began after I was selected as an IBS center director. During that process, I requested the establishment of a new department. To create a new research hub outside the Seoul metropolitan area, it is imperative to attract top-tier talent. By establishing a department, we can recruit new faculty and create a foundation for bringing together students and researchers. With the concurrent launch of the IBS research center and the new department, I believe we have secured the resources and opportunities to pursue the research we are truly passionate about and to contribute to both national and regional development.

Q3. Could you explain the field of microbiome–body–brain research in simple terms?

Traditional neuroscience has primarily developed by examining how neurons within the brain are activated or inhibited, and how various groups of neurons contribute to behaviors such as eating, sleeping, and mating. However, the importance of the connections between neurons in the brain and organs throughout the body has recently come to the fore. In particular, the gut is closely linked to the brain, and the gut microbiome also influences this connection. This represents a major paradigm shift in neuroscience, and leading research institutions around the world are currently focusing their efforts on this field.

Q4. You have been studying how interoceptive neurons connect the brain and internal organs. What does it mean to sense the state of the body, as opposed to sensing the outside world?

The five senses we commonly talk about—sight, hearing, smell, taste, and touch—have been studied extensively for a long time. Much is now known about how their receptors function, and research in these areas has been recognized with numerous Nobel Prizes.In contrast, interoception, which involves sensing the state of the body, is a relatively understudied field.It is one of the areas that our lab pioneered.This internal sensory system is closely linked not only to health but also to a wide range of diseases, and it will become increasingly important. It is also crucial for maintaining the body’s homeostasis.I believe this will become a highly impactful area of research.

Q5. Can we understand hunger, satiety, and cravings for salty or sweet foods as the result of signals exchanged between the body and the brain?

That is correct. When we are deficient in certain nutrients, the body detects that deficit and prompts us to seek out those nutrients.If you go without food for a long time, you develop a desire for food; if you don’t consume enough protein, you might find yourself craving meat. These signals are first detected in the gut.The gut senses that the body is low on salt or protein and transmits that information to the brain via the gut–brain axis.We then engage in behaviors to consume the necessary nutrients.Everyday appetite and preferences for particular foods can therefore be understood as the result of sophisticated physiological signaling between the body and the brain.

Q6. Using fruit flies as a model, you have identified brain–gut neural circuits involved in feeding, metabolism, and hormone regulation. What clues can research on such small organisms provide for understanding the human body and disease?

Fruit flies are easy to raise, amenable to genetic manipulation, and supported by a wide array of well-established research tools. Of course, the extent to which findings from fruit fly research can be directly applied to humans must continue to be verified.However, fruit flies and mammals share many fundamental biological mechanisms.In fact, we have confirmed that some of the mechanisms we discovered in fruit flies operate similarly in mammals such as mice.While directly studying humans or mammals is highly time-consuming and expensive, fruit flies serve as a powerful model that allows for efficient testing. They can play a crucial role in research aimed at uncovering fundamental biological principles.

Q7. How can the research center’s work on nutrient sensing help us understand metabolic diseases such as obesity, diabetes, and hypertension?

Basic science cannot be separated from medicine. For example, if the sensors that detect nutrients in our bodies do not function properly, we may continue eating even when we do not need to.This can lead to obesity and subsequent metabolic diseases such as diabetes.If our salt-sensing mechanisms do not function properly, it can result in disrupted fluid balance and elevated blood pressure.Therefore, uncovering the fundamental mechanisms of nutrient sensing can provide an important pathway toward understanding chronic conditions such as obesity, diabetes, and hypertension, as well as their complications.

Q8. The center is also garnering attention in the field of neurological disorders such as Parkinson’s and Alzheimer’s. What is the primary question the center aims to address in this field?

Many studies have raised the possibility that various diseases may originate in the gut, and our center has also come to focus on the significant role the gut plays in neurological and psychiatric disorders. In the case of Parkinson’s disease, it is suggested that a harmful protein called alpha-synuclein may aggregate abnormally in the gut and then travel to the brain along the gut–brain axis. This can subsequently affect specific neurons in the brain, leading to disease. Moving forward, we intend to elucidate the role that interactions among the gut, brain, and microbiome play in the onset and progression of neurological disorders.

Q9. Following the center’s launch, you have already published a paper in Science. Based on this achievement, in what direction would you like to lead the center in the future?

We were fortunate that the paper was published successfully. The research direction of our center is to conduct original and creative research that others are not pursuing. Questions that are nearly impossible to answer rarely lead to good science, and questions that are easily answerable but uninteresting cannot be considered good science either. The key is to find questions that are interesting and meaningful, yet still feasible for us to tackle. I always tell my students that we should look for such questions. As I mentor our students, my affection for them has grown even deeper. I hope our students grow into excellent scientists, so that Korea might one day produce a Nobel laureate in science and help lead global scientific progress.

Q10. What is the first priority for the newly launched center and department? Also, what would you like to say to the students who will be studying and conducting research in this field?

Research on internal nutrient sensing, the microbiome, and the gut–brain axis is an emerging field. There are many questions waiting to be answered and plenty of topics for students to take on. I look forward to working with them on engaging and meaningful research here and helping them grow into outstanding scientists. This field will only become more important in the future. I hope that GIST will serve as a hub for research and education that leads the field.