March 9, 2023 – From ICT Tac with kombucha tea, gut health is having a moment – after we’ve been hearing about it for years already. Well Named.
Your gut — and its diverse mix of bacteria known as the microbiome — isn’t just about digestion anymore. Gut “health” is also linked to the health of your heart, brain, immune system, etc.
The problem: Much of what goes on there and what bacteria populate it at what levels — and how to interpret it all — remains a mystery. The study of the intestine is delicate. Animal research may not be helpful because animals have different digestive enzymes and gut bacteria than humans. And typical lab tests, like culturing cells in a petri dish, don’t capture the complexity of the gut, a part of the body where many cell types grow and interact in a moist, fluid, and free-flowing environment. oxygen.
An emerging technology, called “gut on a chip,” promises to change all that, opening the door to experiences never before possible and promising to advance medical research, according to a new paper published in APL Bioengineering.
Your gut on a chip
It’s one of the latest advancements in ‘organs on a chip’ technology, the concept of placing human cells in a device designed to mimic the activity of human organs. Scientists have developed models to simulate organs such as the lungs, kidneys and vagina.
To build a gut on a chip, scientists grow cells from gut tissue and bacteria.
“These cells don’t grow easily,” says study author Amin Valiei, PhD, a postdoctoral researcher at the University of California, Berkeley. “They need a specific environment.”
To create this environment, the researchers placed the cells in tiny channels designed to allow fluid flow and mimic the forces present in the gut. This means that cells can interact with each other just as they would inside the human body.
“These models are becoming more and more advanced,” says Valiei. “Compared to a few years ago, we now have models that can accommodate a few cell types.”
Why It Matters: Medications, Diseases, and Dysbiosis
Researchers can experiment with patterns that would be difficult or impossible in humans.
“These devices could be particularly useful at the hypothesis stage for testing new drugs and therapeutics,” says Valiei.
Valiei and his colleagues at UC Berkeley’s Molecular Cellular Biomechanics Laboratory are studying how different bacterial species interact in these gut chip models. In particular, they are exploring how certain harmful bacteria can take hold in the gut – a phenomenon known as dysbiosis this is linked to a range of conditions such as inflammatory bowel disease (IBD), irritable bowel syndrome (IBS), diabetes, obesity, cancer and heart problems.
Researchers are also using gut-on-a-chip models to study IBD, colorectal cancer, and even the effects of viruses like COVID-19 on gut function.
To understand how diseases develop, we need to break things down into basic steps, and gut-on-a-chip models could help researchers do that, says Christopher Chang, MD, PhD, gastroenterologist at the Raymond G. Murphy VA Medical Center in Albuquerque, NM, and the University of New Mexico. (Chang did not participate in the study.)
“We can identify literally thousands of species in the gut, and we kind of know, in broad strokes, which microbes are considered beneficial and which microbes are considered non-beneficial,” he says.
But how do individual bugs fit into a community? And what combinations lead to a healthy gut versus an unhealthy gut? The answers to these questions remain unclear.
“We have ways to manipulate the microbiome, through different antibiotics, probiotics, and fecal microbiota transplants,” Chang says. “But we have to know: what should we manipulate?
Room for improvement
One part of the gut not yet reflected in gut chip models is the enteric nervous system, aka our “second brain” — neurons embedded in the gastrointestinal tract, Chang says. This is how the gut and the brain communicate, and its dysfunction is linked to bowel disorders such as IBS.
People with IBS may have pain, diarrhea, or constipation even though their bowel tissue appears normal on biopsies. Gut-on-a-chip models might be less useful in revealing information about these disorders, although they can still help answer fundamental questions.
The gut-brain connection is still being clarified, so as science evolves, researchers may be able to add new information to future gut-on-a-chip models.
Gut-on-a-chip models could also be useful beyond disease, Valiei says. Any medicine you swallow passes through your digestive tract. If researchers can use on-chip gut models to find out precisely how we digest and absorb drugs, they might be able to refine how we use those drugs.
For the time being, efforts are being made to generalize this technology. Due to the need for more research, refining the technology, and gathering enough data to satisfy regulators, it may be several more years before this type of “precision” medicine is accurate enough to truly personalize its use for patients. But according to Valiei, it is indeed an accurate preview of what is to come.
