As this therapeutic approach gains regulatory approval, clinical laboratory tests to determine condition of patient’s gut microbiota and monitor therapy will be needed
Some developments in the clinical laboratory industry are less about diagnostic tests and more about novel approaches to therapy. Such is the case with a new carbon bead technology developed by researchers from University College London (UCL) and the Royal Free Hospital intended to remove harmful bacteria toxins from the gut before they leak to the liver. The macroporous beads, which come in small pouches, are delivered orally and could be utilized in the future to treat a number of diseases.
Why is this relevant? Once a new treatment is accepted for clinical use, demand increases for a clinical laboratory test that confirms the therapy will likely work and to monitor its progress.
In collaboration with Yaqrit, a UK-based life sciences company that develops treatments for chronic liver disease, the UCL and Royal Free Hospital scientists engineered the carbon beads—known as CARBALIVE—to help restore gut health. They measured the technology’s impact on liver, kidney, and brain function in both rats and mice.
“The influence of the gut microbiome on health is only just beginning to be fully appreciated,” said Rajiv Jalan, PhD, Professor of Hepatology at UCL in a press release. “When the balance of the microbiome is upset, ‘bad’ bacteria can proliferate and out-compete the ‘good’ bacteria that keeps the gut healthy.
“One of the ways [the ‘bad’ bacteria] do this is by excreting endotoxin, toxic metabolites, and cytokines that transform the gut environment to make it more favorable to them and hostile to good bacteria,” he continued. “These substances, particularly endotoxin, can trigger gut inflammation and increase the leakiness of the gut wall, resulting in damage to other organs such as the liver, kidneys, and brain.”
“I have high hopes that the positive impact of these carbon beads in animal models will be seen in humans, which is exciting not just for the treatment of liver disease but potentially any health condition that is caused or exacerbated by a gut microbiome that doesn’t work as it should,” said Rajiv Jalan, PhD (above), Professor of Hepatology, University College London, in a press release. “This might include conditions such as irritable bowel syndrome (IBS), for example, which is on the rise in many countries.” Though not a clinical laboratory diagnostic test, new therapies like CARBALIVE could be a boon to physicians treating patients with IBS and other gastrointestinal conditions.
Developing the Carbon Beads
The team discovered CARBALIVE is effective in the prevention of liver scarring and injury in animals with cirrhosis when ingested daily for several weeks. They also found a reduced mortality rate in test animals with acute-on-chronic-liver-failure (ACLF).
After achieving success with CARBALIVE in animals, the researchers tested the technology on 28 cirrhosis patients. The carbon beads proved to be safe for humans and had inconsequential side effects.
“In cirrhosis, a condition characterized by scarring of the liver, it is known that inflammation caused by endotoxins can exacerbate liver damage,” Jalan explained. “Part of the standard treatment for cirrhosis is antibiotics aimed at controlling bad bacteria, but this comes with the risk of antibiotic resistance and is only used in late-stage disease.”
The beads, which are smaller than a grain of salt, contain an exclusive physical structure that absorbs large and small molecules in the gut. They are intended to be taken with water at bedtime as harmful bacteria is more likely to circulate through the body at night which could result in damage. The carbon beads do not kill bacteria, which decreases the risk of antibiotic resistance. They eventually pass through the body as waste.
“They work by absorbing the endotoxins and other metabolites produced by ‘bad’ bacteria in the gut, creating a better environment for the good bacteria to flourish and helping to restore microbiome health,” said Michal Kowalski, M.Sc.Eng, Director and VP of Operations at Yaqrit, in the UCL news release.
“This prevents these toxins from leaching into other areas of the body and causing damage, as they do in cirrhosis,” he added. “The results in animal models are very positive, with reduction in gut permeability, liver injury, as well as brain and kidney dysfunction.”
Additional Research
The researchers plan to perform further clinical trials in humans to determine if the carbon beads are effective at slowing the progression of liver disease. If the benefits that were observed in lab animals prove to be compelling in humans, the technology may become an invaluable tool for the treatment of liver disease and other diseases associated with poor microbiome health in the future.
According to the American Liver Foundation, 4.5 million adults in the US have been diagnosed with liver disease. However, it is estimated that 80 to 100 million adults have some form of fatty liver disease and are unaware of it. Liver disease was the 12th leading cause of death in the US in 2020 with 51,642 adults perishing from the disease that year.
According to BMC Public Health, globally there were 2.05 million new cases of liver cirrhosis diagnosed in 2019. In that year, 1.47 million people around the world died from the disease.
More research and clinical studies are needed before this novel technology can be used clinically. When and if that happens, the demand for clinical laboratory tests that measure microbiome deficiencies and monitor patient progress during therapy will likely be high.
Scientists turned to metabolomics to find cause of biological aging and release index of 25 metabolites that predict healthy and rapid agers
Researchers at the University of Pittsburg Medical Center and the University of Pittsburgh School of Medicine have identified biomarkers in human blood which appear to affect biological aging (aka, senescence). Since biological aging is connected to a person’s overall condition, further research and studies confirming UPMC’s findings will likely lead to a new panel of tests clinical laboratories can run to support physicians’ assessment of their patients’ health.
UPMC’s research “points to pathways and compounds that may underlie biological age, shedding light on why people age differently and suggesting novel targets for interventions that could slow aging and promote health span, the length of time a person is healthy,” according to a UPMC news release.
“We decided to look at metabolites because they’re very dynamic,” Aditi Gurkar, PhD, the study’s senior author, told the Pittsburgh Post-Gazette. Gurkar is Assistant Professor of Medicine, Division of Geriatric Medicine, Aging Institute at the University of Pittsburg. “They can change because of the diet, they can change because of exercise, they can change because of lifestyle changes like smoking,” she added.
The scientists identified 25 metabolites that “showed clear differences” in the metabolomes of both healthy and rapid agers. Based on those findings, the researchers developed the Healthy Aging Metabolic (HAM) Index, a panel of metabolites that predicted healthy agers regardless of gender or race.
“Age is more than just a number,” said Aditi Gurkar, PhD (above), Assistant Professor of Geriatric Medicine at University of Pittsburg School of Medicine and the study’s senior author in a news release. “Imagine two people aged 65: One rides a bike to work and goes skiing on the weekends and the other can’t climb a flight of stairs. They have the same chronological age, but very different biological ages. Why do these two people age differently? This question drives my research.” Gurkar’s research may one day lead to new clinical laboratory tests physicians will order when evaluating their patients’ health. (Photo copyright: University of Pittsburg.)
Clear Differences in Metabolites
According to the National Cancer Institute, a metabolite is a “substance made or used when the body breaks down food, drugs, or chemicals, or its own tissue (for example, fat or muscle tissue). This process, called metabolism, makes energy and the materials needed for growth, reproduction, and maintaining health. It also helps get rid of toxic substances.”
The UPMC researchers used metabolomics—the study of chemical process in the body that involves metabolites, other processes, and biproducts of cell metabolism—to create a “molecular fingerprint” of blood drawn from individuals in two separate study groups.
They included:
People over age 75 able to walk a flight of stairs or walk for 15 minutes without a break, and
People, age 65 to 75, who needed to rest during stair climbing and walk challenges.
The researchers found “clear differences” in the metabolomes of healthy agers as compared to rapid agers, suggesting that “metabolites in the blood could reflect biological age,” according to the UPMC news release.
“Other studies have looked at genetics to measure biological aging, but genes are very static. The genes you’re born with are the genes you die with,” said Gurkar in the news release.
Past studies on aging have explored other markers of biological age such as low grade-inflammation, muscle mass, and physical strength. But those markers fell short in “representing complexity of biological aging,” the UPMC study authors wrote in Aging Cell.
“One potential advantage of metabolomics over other ‘omic’ approaches is that metabolites are the final downstream products, and changes are closely related to the immediate (path) physiologic state of an individual,” they added.
The researchers used an artificial intelligence (AI) model that could identify “potential drivers of biological traits” and found three metabolites “that were most likely to promote healthy aging or drive rapid aging. In future research, they plan to delve into how these metabolites, and the molecular pathways that produce them, contribute to biological aging and explore interventions that could slow this process,” the new release noted.
“While it’s great that we can predict biological aging in older adults, what would be even more exciting is a blood test that, for example, can tell someone who’s 35 that they have a biological age more like a 45-year-old,” Gurkar said. “That person could then think about changing aspects of their lifestyle early—whether that’s improving their sleep, diet or exercise regime—to hopefully reverse their biological age.”
Looking Ahead
The UPMC scientists plan more studies to explore metabolites that promote healthy aging and rapid aging, and interventions to slow disease progression.
It’s possible that the blood-based HAM Index may one day become a diagnostic tool physicians and clinical laboratories use to aid monitoring of chronic diseases. As a commonly ordered blood test, it could help people find out biological age and make necessary lifestyle changes to improve their health and longevity.
With the incidence of chronic disease a major problem in the US and other developed countries, a useful diagnostic and monitoring tool like HAM could become a commonly ordered diagnostic procedure. In turn, that would allow clinical laboratories to track the same patient over many years, with the ability to use multi-year lab test data to flag patients whose biomarkers are changing in the wrong direction—thus enabling physicians to be proactive in treating their patients.
With further research, clinical laboratories may soon be performing macrobiotic testing to measure certain bacterial levels in patients’ gut bacteria
New insights from the University of Chicago (UChicago) into how human microbiota (aka, gut bacteria) play a role in food allergies has the potential to change the way a number of gastrointestinal health conditions are diagnosed and treated. This would give microbiologists and clinical laboratories a greater role in helping physicians diagnose, treat, and monitor patients with these health issues.
Past research has shown that certain gut bacteria can prevent antigens that trigger allergic reactions from entering the bloodstream. For example, Clostridium bacteria in the stomach produce a short-chain fatty acid known as butyrate, a metabolite that promotes the growth of healthy bacteria in the gut. This helps keep the microbiome in balance.
One way butyrate is created in the gut is through the fermentation of fiber. However, a lack of fiber in the diet can deplete the production of butyrate and cause the microbiome to be out of balance. When this happens, a state known as dysbiosis occurs that disrupts the microbiome and can lead to food allergies.
Without butyrate, the gut lining can become permeable and allow food to leak out of the gastrointestinal tract and into the body’s circulatory system. This reaction can trigger a potentially fatal anaphylactic response in the form of a food allergy. Thus, eating enough fiber is critical to the production of butyrate and to maintaining a balanced microbiome.
But today’s western diet can be dangerously low in soluble fiber. Therefore, the scientists at the University of Chicago have developed “a special type of polymeric molecule to deliver a crucial metabolite produced by these bacteria directly to the gut, where it helps restore the intestinal lining and allows the beneficial bacteria to flourish. … these polymers, called micelles, can be designed to release a payload of butyrate, a molecule that is known to help prevent food allergies, directly in the small and large intestines,” according to a UChicago news release.
This will be of interest to microbiologists, in particular. It’s another example of researchers connecting a specific species of bacteria in the human microbiome to a specific benefit.
“It’s very unlikely that butyrate is the only relevant metabolite, but the beauty of this platform is that we can make polymers with other microbial metabolites that could be administered in conjunction with butyrate or other therapies,” said Cathryn Nagler, PhD (above), Bunning Family Professor in the Biological Sciences Division and Pritzker School of Molecular Engineering at UChicago and a senior author of the study. “So, the potential for the polymer platform is pretty much wide open.” As further research validates these findings, clinical labs are likely to be doing microbiomic testing to monitor these therapies. (Photo copyright: University of Chicago.)
Restoring Butyrate in the Gut
One way to treat this anomaly has been through a microbiota transplant—also called a fecal biota transplant—where the administration of a solution of fecal matter is transplanted from a donor into the intestinal tract of the recipient. This transplant alters the recipient’s gut microbial composition to a healthier state, but it has had mixed results.
So, the UChicago researchers went in another direction (literally). They created an oral solution of butyrate and administered it to mice in the lab. The purpose of the solution was to thwart an allergic reaction when the mice were exposed to peanuts.
But there was a problem with their oral solution. It was repulsive.
“Butyrate has a very bad smell, like dog poop and rancid butter, and it also tastes bad, so people wouldn’t want to swallow it,” Shijie Cao, PhD, Postdoctoral Scientist at the Pritzker School of Molecular Engineering at UChicago and one of the researchers who worked on the project, told Medical News Today.
The researchers developed a new configuration of polymers that masked the butyrate. They then delivered these polymer micelles directly into the digestive systems of mice that lacked healthy gut bacteria or a proper gut linings.
The treatment restored the microbiome by increasing the production of peptides that obliterate harmful bacteria. This allowed more of the beneficial butyrate-producing bacteria to emerge, which protected the mice from an anaphylactic reaction to peanuts and even reduced the symptom severity in an ulcerative colitis model.
“We were delighted to see that our drug both replenished the levels of butyrate present in the gut and helped the population of butyrate-producing bacteria to expand,” said Cathryn Nagler, PhD, Bunning Family Professor in the Biological Sciences Division and Pritzker School of Molecular Engineering at the University of Chicago and a senior author of the study, in the press release. “That will likely have implications not only for food allergy and inflammatory bowel disease (IBD), but also for the whole set of non-communicable chronic diseases that have been rising over the last 30 years, in response to lifestyle changes and overuse of antibiotics in our society.”
Future Benefits of UChicago Treatment
According to data from the Asthma and Allergy Foundation of America, about 20 million Americans suffered from food allergies in 2021. This includes approximately 16 million (6.2%) of adults and four million (5.8%) of children. The most common allergens for adults are shellfish, peanuts, and tree nuts, while the most common allergens for children are milk, eggs, and peanuts.
The best way to prevent an allergic reaction to a trigger food is strict avoidance. But this can be difficult to ensure outside of the home. Therefore, scientists are searching for ways to prevent food allergies from happening in the first place. The micelle technology could be adapted to deliver other metabolites and molecules which may make it a potential platform for treating allergies as well as other inflammatory gastrointestinal diseases.
“It’s a very flexible chemistry that allows us to target different parts of the gut,” said Jeffrey Hubbell, PhD, Eugene Bell Professor in Tissue Engineering and Vice Dean and Executive Officer at UChicago’s Pritzker School of Molecular Engineering and one of the project’s principal investigators, in the UChicago news release. “And because we’re delivering a metabolite like butyrate, it’s antigen-agnostic. It’s one agent for many different allergic indications, such as peanut or milk allergies. Once we begin working on clinical trials, that will be a huge benefit.”
Nagler and Hubbell have co-founded a company called ClostraBio to further the development of butyrate micelles into a commercially available treatment for peanut and other food allergies. They hope to begin clinical trials within the next 18 months and expand the technology to other applications as well.
Further research and clinical trials are needed to prove the validity of using polymer micelles in the treatment of diseases. But it is possible that clinical laboratories will be performing microbiomic testing in the future to help alleviate allergic reactions to food and other substances.
Pathologists and clinical laboratory professionals can expect to see new molecular test development as researchers develop new biomarkers in the wake of expanded knowledge of the genome-metabolome-diseasome correlates
One field of science that bears great potential for use in diagnostics and medical laboratory testing involves the human metabolome. Researchers are gaining more understanding of the genetic underpinnings of complex disease and drug response through metabolic pathways.
For example, scientists at the Wellcome Trust Sanger Institute (WTSI) in the United Kingdom have linked 145 genetic regions with more than 400 molecules involved in metabolism in human blood, a story in Genetic Engineering News recently reported. The resulting atlas of associations will enable identification of genes that could be targeted in the development of drugs and clinical laboratory test. (more…)