Behavior - it's all in our gut
Does the way we behave depend in part on the specific community of microbes living within each of us? Dr. Michael Montague studies the microbiome of a free-ranging population of primates to understand how it shapes their social interactions and vice versa.
Good news was followed by a disaster. Just a few days after Michael Montague heard that he won the 2017 QIAGEN Microbiome Award, Hurricane Maria devastated much of Puerto Rico. The hurricane also swept over a small research island called Cayo Santiago, where scientists have been observing hundreds of rhesus macaque monkeys for decades. The island was the precise spot where Dr. Montague had planned to realize his project.
Is the microbiome linked to social behavior?
That is what studies on wild chimpanzees and baboons have shown. In humans, microbiome variation is also linked to health issues, such as obesity and autoimmune disorders. So different questions arise, including how might animals modify their behavior to maintain a healthy and diverse set of microbes. It’s likely that beneficial microbes provide animal hosts with the immunity and metabolism to forage and find mates, strengthen their social interactions with their preferred group mates, and – most importantly – avoid predators or other threats.
So what will your QIAGEN-supported project look like?
Our proposal specifically examines how varying degrees of social interaction impact the gut microbiome in rhesus monkeys, while also exploring how the diversity of gut microbes influences levels of peripheral and central serotonin. Some species of gut bacteria can directly metabolize tryptophan, a crucial precursor used in the manufacture of serotonin. Competition for tryptophan is therefore likely to impact host serotonin availability.
Why do you look at serotonin?
Serotonin is a key neurotransmitter influencing our digestive tract, cardiovascular system and our brain. It is known to play a role in modulating mood, appetite, sleep, cognition, arousal or pain – thus, it also has an important effect on behavioral patterns.
Can you tell how your project will unfold?
We will first measure female grooming behavior, followed by shotgun sequencing of gut microbiomes from fecal samples and serotonin collection from various bodily fluids. We expect socially integrated females who interact more frequently in grooming to possess more diverse gut microbiomes and different levels of serotonin. Resulting data will enable us to clarify how the gut microbiome affects serotonin synthesis and the potential effects of serotonin and gut microbial composition on social behavior.
Do you use QIAGEN technology doing your work?
I made use of QIAGEN extraction kits throughout my graduate training. They were easy to use and produced quality template DNA from low-quality fecal samples collected in the field. Our current work on skin and fecal microbiomes makes use of the DNeasy Power Soil Kits.
What is your ambition with this research?
The coevolution of hosts and their microbiome represents a complex and integrated arrangement. If we can illustrate a comprehensive picture of microbiome diversity within the context of a population’s social structure, then we might gain a better appreciation of being social as an evolutionary mechanism. I anticipate testing whether and how varying degrees of social integration impacts the microbiome and serotonin levels, since this represents a critical step in our understanding of the gut-brain axis.
Do you find it more fascinating or more frightening that our behavior is possibly shaped by countless microorganisms in and around us?
I’m fascinated by this idea. This is really about the big question of how our brain processes information to elicit certain behaviors, specifically spontaneous behaviors such as laughing. How might our moods and reactions be shaped in part from viruses and bacteria? If you add the question about how different behaviors evolved in the first place, and ponder the microbiome’s role in all of this, then these are extremely exciting questions. Individuals and the microbiome influence each other mutually; we are part of one ecosystem.