Digestive Health

Increasing Prebiotics in Your Diet Improves Digestive Health, Sleep and More

Confused about the difference between probiotics and prebiotics and how they work together? Here, we will take a brief look at what probiotics and prebiotics are, break down the differences between these important digestive helpers and learn how increasing the prebiotics in your diet not only improves digestion but also supports immune function, promotes sleep, lowers stress and provides many other benefits.

What Are Prebiotics?

Prebiotics are types of nondigestible fibers and sugars found in certain foods. Because your body can’t break them down completely, these substances pass undigested through the upper parts of the gastrointestinal tract. Once the prebiotic compounds reach the colon, they’re fermented by the bacteria residing in the gut. There, they feed the communities of bacteria that make up the gut’s microbiota.

So, what exactly is the difference then between prebiotics and probiotics? The term “probiotics” typically refers to foods and supplements that contain live microorganisms known to be beneficial to gut health. Conversely, “prebiotics” are compounds that serve as food for the microorganisms that live in the gut. The also-related but less well-known “postbiotics” are the byproduct that occurs as a result of gut bacteria fermenting the prebiotic compounds. Individually, each of these components possesses a number of health benefits while also working together to improve digestive health and overall well-being.

Why Are Prebiotics Important?

The human body is a host to trillions of bacteria, the vast majority of which live within our large intestines. Many of these bacteria are critical to bodily functions. The bacteria in our guts not only aid in the digestion of food and absorption of nutrients but also help to regulate hormone production and neurotransmitter release, with a direct effect on the immune system and the body’s ability to cope with stress.

Because our guts are so integral to many bodily functions, the abundance and diversity of the good bacteria in our guts is important to our overall health. Prebiotics act as a food source for these bacterial colonies that reside within our GI tracts. Working together, prebiotics and probiotics have been shown to significantly improve health outcomes.

What Are the Benefits of Prebiotics?

Prebiotics improve digestion and promote a healthy gut. Acting as food for good bacteria, prebiotics encourage the growth of the beneficial microbes residing in our guts. When these otherwise nondigestible fibers are metabolized by friendly gut bacteria, the byproduct is another group of beneficial compounds known as short-chain fatty acids (SCFAs). SCFAs strengthen the intestinal lining, aid digestion, improve the symptoms of inflammatory bowel conditions and may even lower the chances of developing colorectal cancer.

Prebiotics reduce your risk for cardiovascular disease. Studies have shown that combining prebiotics and probiotics helps to regulate insulin signaling, lower “bad” cholesterol, balance electrolyte levels and reduce blood pressure, all factors that greatly reduce the risk of developing cardiovascular problems.

Prebiotics aid weight loss and the chances of obesity. Numerous studies have indicated that gut dysbiosis can be a contributing factor to weight gain and obesity-related disorders. Increased fiber intake is known to help curb weight gain. Researchers have found that prebiotic fiber regulates the stimulation and suppression of gastrointestinal hormones that control the feelings of hunger and satiation and is associated with a lowered BMI.

Prebiotics can help to reduce inflammation. Inflammation is believed to be a contributing factor for chronic conditions such as heart disease, diabetes and even some cancers. Studies have demonstrated that increased intake of prebiotic fiber lowers systemic inflammation. Research indicates that this association may be due to the production of SCFAs that occurs during prebiotic fermentation.

Prebiotics improve the body’s immune system response. A healthy gut is key to a strong immune system.Recent findings have shown that adding more prebiotics into your diet elevates SCFA levels and increases the expression of antibodies and antioxiants, important for helping the body to fight off illness and disease.

Prebiotics promote healthier, stronger bones. Imbalances to the gut microbiota have been tied to cases of disease and loss of density within bones. According to research, upping intake of prebiotics improves bone strength by increasing calcium absorption and bone density.

Prebiotics may improve sleep quality. Every cell in the human body responds to circadian rhythms, and this includes the microbial life within us. Under normal circumstances, subjects with a higher intake of prebiotics tend to spend more time in the restorative sleep phase, except for after stressful events, which observed longer periods of REM sleep, the phase of sleep thought to help recover from stress. This suggests that prebiotics encourage better, more restful sleep and help to ease stress. Prebiotics also alter the release of hormones such as melatonin and serotonin that are known to play a role in or have an effect on sleep and sleep quality.

Prebiotics help to regulate moods and hormone levels. As our knowledge of the gut-brain connection grows, it’s becoming more and more clear that many conditions, including mental health issues, are affected by gut health. Not only does our gut flora affect bodily function, but studies suggest that our gut’s microbial makeup may even be responsible for how bodily systems, such as our stress response system, are actually developed. Increased consumption of prebiotics has been shown to improve stress responses, reduce cortisol levels and alleviate feelings of depression and anxiety.

How to Incorporate More Prebiotics Into Your Diet

Want to know how you can increase your daily intake of prebiotics? There are a handful of prebiotic-rich foods that you can add to your diet. Remember that, as with most foods, cooking changes the nutritional makeup. For the most benefit, try to consume foods that are raw and unprocessed. Here are a few food choices that are packed with health-promoting prebiotics:

asparagus
chicory root
dandelion greens
garlic
jicama
leeks
onions
under-ripened bananas

Dietary supplements are also available for those unable to fit enough prebiotics into their diet. Look for supplements that combine both prebiotics and probiotics for the greatest impact.

Avoiding Carbs May Negatively Impact Gut Bacteria

Oct 11 by Ewcopywriting

While sitting down to a never-ending pasta bowl probably isn’t the healthiest interpretation, a growing body of research suggests that eating carbohydrates does come with some benefits. Low- and no-carb diets have become extremely popular weight loss methods, but could they be doing more long-term harm than good? New research suggests there could be a negative link between a low carb diet and gut health.

Investigating Link Between a Low Carb Diet and Gut Health

As Oleg Paliy, Ph.D., Associate Professor at Wright State University and corresponding author of a new study investigating the matter, commented, “the relative beneficial and harmful effects of the high-carb and high-fat diets are a subject of many studies and debates.”

Previous research suggests that a low-carb diet may be useful in helping treat dementia, psychiatric conditions, and perhaps even cancer. However, overall, research seems to support the idea that consuming at least some carbs is necessary for the best health outcomes.

The latest findings indicate that if followed long-term, a low-carb diet could actually shorten your lifespan by up to four years, significantly increasing one’s risk for cancer, coronary heart disease and stroke. Recently, scientists revealed that a low-carb diet could cause insulin resistance and raise one’s risk for Type 2 diabetes. Now, new research published in Applied and Environmental Microbiology suggests that not eating enough carbs harms gut health, a situation which can increase your risk for colorectal cancer.

The Importance of Healthy Gut Bacteria

Each of us shares a symbiotic cohabitation with trillions of microorganisms existing both on and inside our bodies, the largest number of which reside within our gastrointestinal tracts. The bacterial colonies living in the gut, referred to as the gut’s flora or microbiota, are a key factor in health and play a large part of many critical bodily functions. They directly influence key aspects of health such as brain function, hormone regulation, immune response as well as vitamin and nutrient production and absorption.

Dysbiosis of the gut’s microbiota has been implicated in the development of or complication in conditions such as cancer, diabetes, cardiovascular disease, obesity and asthma. Such imbalances have also been found to contribute to psychiatric and neurological disorders such as depression, autism, PTSD, multiple sclerosis and Alzheimer’s disease. Evidence has shown that even the smallest imbalance to these complex microbial communities can quickly lead to illness and mental health decline.

Carb Consumption Benefits Gut Bacteria

Comparing a high-fat, no-carb diet to a typical Western diet, researchers from Wright State University investigated diet’s effect on gut health and found that the switch from a balanced diet to a higher-fat, no-carb diet caused a noticeable shift in the strains of bacteria that are present within the gut. The no-carb diet was found to increase the types of fatty-acid metabolizing bacteria and decrease those responsible for metabolizing carbs and proteins. The result of this is a decrease in the synthesis of antioxidants and short-chain fatty acids, which, according to the researchers, “[might] potentially have negative health consequences on the host.”

Beneficial antioxidants and short-chain fatty acids are created when the microbes in our guts process carbohydrates. These fatty acids and antioxidants serve to combat DNA damage and the effects of aging. Their presence reduces inflammation, regulates appetite, and lowers the overall risk of colorectal cancer.

Dr. Paliy explained, “intestinal microbes mediate many dietary effects on human health. There, most of these compounds are fermented by gut bacteria. This happens because a significant proportion of dietary carbohydrates, proteins, and fats escapes digestion in the small intestine, and reaches the colon, a section of the gut housing a dense population of microbes.”

So, while a low- or no-carb diet may be helpful for short-term weight loss, following such a regime long-term could result in major disruptions to bowel health.

Simulating the Human Gut

In order to conduct their research, the team used an experimental mechanism that was designed to simulate the gut. The apparatus integrated three glass containers, each meant to simulate a different region of the human colon. Each vessel was “seeded” with gut microbe samples that were supplied by human fecal donors.

These colonies of bacteria were fed nutrients that were meant to mimic either a balanced Western diet or that a diet comprised only of dietary fats. The team then analyzed the changes to the microbiota using high-throughput sequencing to evaluate the composition and high-performance liquid chromatography to measure the metabolites of the bacterial colonies.

Their observations revealed that switching from a Western diet to a high-fat diet caused an increase to the populations of bacteria that metabolize fatty acids, including Alistipes, Bilophila and numerous types of Gammaproteobacteria, while there was a decline among bacterial populations that process carbohydrates and proteins, including species of Bacteroides, Clostridium and Roseburia.

The loss of bacteria that metabolizes carbohydrates caused a sharp decrease in the production of short chain fatty acids. The researchers also observed a significant drop in antioxidant production, important beneficial compounds which prevent and repair cellular and DNA damage and help to curb the effects of age. The team’s findings add to mounting evidence that cutting out carbs may not be the healthiest choice.

How to Promote Healthy Gut Bacteria Diversity

As evidenced, the beneficial bacteria in the gut are essential to the production of vitamins, the absorption of nutrients, the combat of pathogens and a host of other critical functions. There are a number of factors that influence the number of and types of bacteria present in the gut. Here are a few that you can control yourself:

Eat a diverse whole-foods-based diet that consists of plenty of fruits, vegetables and whole grains.
Consume foods that are rich in probiotics. Fermented foods such as sauerkraut, kimchi, kefir, and yogurt are excellent sources of beneficial bacteria.
Eat plenty of prebiotic foods. High-fiber food sources like beans, apples, bananas, and oats are high in prebiotic fiber that promotes that growth of good bacteria.
Take a probiotic supplement containing live strains of beneficial bacteria to help maintain or restore gut balance.
Eat polyphenol-rich foods such as dark chocolate, green tea, olive oil, and red wine. Polyphenolic compounds promote the healthy bacterial growth.
Limite that amount of processed foods and artificial sweeteners that you consume. Highly-processed foods and sugars fuel the bad bacteria in the gut, which can lower the number of good bacteria.

Probiotic Supplementation Proven to Protect Bone Health in Women

Aug 21 by Ewcopywriting Leave a Comment

As adults grow older, their bones become more brittle and, as a result, they can fracture more easily. While this phenomenon can affect both men and women, women are more at risk for bone loss as they age, suffering more commonly from conditions such as osteoporosis and osteopenia. Women over 80 years of age are at the highest risk for developing osteoporosis. Compounding the problem is the fact that osteoporosis is rarely identified until an actual bone fracture occurs.

Due to these alarming facts, a recent study, conducted at the Sahlgrenska University Hospital in Mölndal, Sweden focused on the effect that probiotics had on bone health in women. In the study, comprised of older women, subjects were divided into two equal groups. The test group received probiotic supplements, while the control group were given placebo replacements. When bone health of the women taking probiotics was compared to those who only received a placebo, the women taking the probiotics were shown to have experienced half as much bone loss, suggesting that probiotics protect bone health.

Probiotics Protect Bone Health in Older Women

The study looked at probiotics as a means of preventing fractures in elderly women. Researchers took a pool of 90 test subjects, comprised of women with an average age of 75, and administered either probiotics or placebos in daily dosages. During the year-long experiment, both researchers and test subjects were kept in the dark as to which women were receiving the probiotics.

CT scans were taken of each subject’s lower legs at the start of the study, and again after the 12-month term had concluded. When the scans were compared, researchers found that the women on the powdered probiotic supplement developed only half the bone degradation of the women taking the placebo. Additionally, researchers noted that the probiotics didn’t cause any negative side effects in the subjects.

Researchers are hopeful that the study’s findings will be used to benefit elderly patients. Previously, it has been noted that beneficial stomach bacteria helped protect the bone structure in mice, but this was the first time probiotic supplements were tested in humans. The results of the research may provide hope for preventing osteoporosis through regular doses of probiotic supplements.

Everyone Can Benefit from Supplementing With Probiotics

Through this study and other types of research, we have learned that probiotics protect bone health in a number of ways. They generally increase bone mass and prevent the breakdown of our bones, while also storing up higher levels of calcium and phosphorus in the blood. Combined, these factors can have long-lasting benefits for the skeleton and the various systems in our bodies.

Boosting the level of probiotics in our bodies benefit us by:

helping our bodies absorb calcium and magnesium more efficiently
reducing lactose intolerance
minimizing the symptoms of leaky gut syndrome
alleviating food allergies
strengthening our immune system
inhibiting the activities of dietary phytates, which can negatively impact mineral absorption
allowing our bodies to process phytoestrogens more effectively

Are Probiotics Safe?

As a natural part of your gut’s microbiome, you already have some probiotics in your system. These “friendly bacteria” aid your digestive process and benefit bone health. The Sahlgrenska University Hospital study showed that women taking additional supplements didn’t suffer from side effects that weren’t experienced by the women taking the placebo. This indicates that a supplement shouldn’t negatively impact your health, if you choose to take one.

In fact, boosting your level of probiotics can benefit various health conditions. If you have a sensitive digestive system or an unusually weak immune system, introducing higher levels of probiotics can help strengthen those biological processes. Additionally, probiotic supplements can be taken to help alleviate uncomfortable symptoms of candida. A daily regimen that includes a high-quality probiotic supplement can help you resolve these types of concerns.

Obtaining Probiotics From Your Diet

If you’re still unsure about taking a supplement directly, probiotics can be found in a variety of foods. They’re commonly found in fermented foods, such as yogurts or pickled products. In fact, yogurt and kefir are some of the best sources of probiotics.

The following foods are also good sources of natural probiotics:

buttermilk
sauerkraut
olives
pickled ginger
kimchi
tempeh
miso
pickles
natto

Your doctor or a nutritionist may be able to give you a broader list of foods that contain probiotics. Alternatively, a supplement can be added to a healthy diet that includes these foods to maximize your intake of healthy bacteria. Beginning sooner may help you strengthen your bones before your first fracture occurs.

As these findings and additional research reinforce the idea that probiotics protect bone health, doctors will likely begin prescribing supplements to their older patients. That’s not to say an increased intake of probiotics won’t benefit individuals of any age. Bone strength varies from person to person, so some people may have weaker bones at younger ages. For those individuals, taking probiotic supplements may be just as beneficial in preventing fractures and further bone loss. While there are many ways to strengthen bones naturally, incorporating probiotics in your diet or taking a daily probiotic supplement may be the most promising method yet.

Discovered: How the Immune System Promotes Friendly Gut Bacteria

Aug 09 by Ewcopywriting Leave a Comment

Scientists from Japan’s RIKEN Center for Integrative Medical Science and Kyoto University have uncovered how our guts secrete antibodies that promote good bacteria to flourish. According to their research, the immunoglobulin A (IgA) antibodies secreted in the gut alter gene expression in bacteria, which allows different species of bacteria to work with each other to form a bacterial community that helps to protect our bodies from illness. The team’s latest findings have been published in the Journal of Experimental Medicine.

Immunoglobulin A and the Gut Microbiome

The immune system’s first line of defense, antibodies, also called immunoglobulins, are proteins that our bodies produce in order to protect against microbial pathogens. Previous research has indicated that antibodies played a role in gut health. In a 2002 study, after noticing that mice with low levels of the IgA antibody also possessed atypical microbiomes, the RIKEN team first proposed that IgA antibodies may play a role in the maintenance of bacteria in the body. Until now, however, scientists have been unable to pinpoint the exact nature of this relationship.

Researchers first discovered the IgA antibody around 50 years ago. Approximately two to five grams of the antibody is produced by our intestines every single day. It’s long been believed that the sole role of antibodies is to seek out and destroy bacteria, but we’re now learning that in some cases, antibodies actively work with bacteria, and vice versa, to promote balance in the body. For instance, a 2016 study published in the journal Cell Host & Microbe showed that the bacteria in our guts releases by-products during the metabolic process that actually boost the body’s production of antibodies, highlighting the complex nature of this two-way relationship.

The human body is home to trillions of microorganisms that bear a direct impact on our health and wellbeing. Over a thousand of species of bacteria reside in the gastrointestinal tract alone. They play a critically important part in everything from brain function, hormonal regulation, and nutrient production to disease resistance and immune response.

Immunoglobulin A Promotes Beneficial Bacteria Growth

As well as being the immune system’s most effective defense against pathogenic bacteria, new research has demonstrated how IgA also promotes the growth and maintenance of the gut’s “good” bacteria. A study conducted by Caltech earlier this year and published in the journal Science sought to uncover the methods by which specific strains of bacteria take up a near-permanent residence in our guts and found that IgA was actually responsible for helping certain bacteria to colonize and thrive in our guts.

“It is surprising to find that an immune response actually helps beneficial bacteria to thrive, which in turn helps the host thrive. The study of immunology has mainly been in the context of pathogenic bacteria. But there are trillions of bacteria in the gut, and most of the time none of them are making you sick. Our study shows that there is active immune recognition of these bacteria, but it helps rather than hinders them. This suggests that the immune system is more than just a defense system and antibodies are more than just weapons,” said Gregory Donaldson, study lead.

With the importance of gut health clear, scientists continue to try and unpack the impossibly complex relationship we share with our bacterial guests.

Immunoglobulin A Shapes the Gut Microbiome by Altering Bacterial Gene Expression

In their latest work, researchers from the RIKEN center set out to further study just how IgA promotes healthy bacteria. Antibodies typically respond to “bad” bacteria after recognizing certain proteins that exist on the bacteria’s surface, however, the team found that IgA antibodies were also responding the healthy bacteria in the gut and that one common bacteria found in the gut, Bacteroides thetaiotaomicron (B. theta), was “particularly susceptible” to coating by IgA.

The team discovered that being exposed to IgA causes B. theta to upregulate two proteins, which the team called Mucus-Associated Functional Factors (MAFFs), that help the B. theta to grow in the mucous membrane of the GI tract as well as producing metabolites that promote the flourishing of other beneficial bacteria as well.

“We knew that immunoglobulin A contributed in some way to gut health, but it was exciting to discover this new mechanism, the MAFF system, that actually promotes symbiosis among the bacteria that inhabit the mucous membrane of the gut,” said lead author of the study Keiichiro Suzuki in a press release.

The team hopes that their findings will help pave the way for new treatments for conditions such as inflammatory bowel disease. According to Suzuki, “the MAFF system is also present in humans so it is an interesting target of research, but there is still much to be investigated. We need to identify its molecular target and find out how its expression is regulated along with neighboring genetic elements, with the hope that answering these questions could lead to the development of new methods for therapies or prophylaxis of inflammatory bowel disease.”

Tips to Promote a Healthy Microbiome and Boost Immunity

There are a number of simple, natural ways to promote a healthy balance of friendly gut bacteria for optimal immunity:

Eat a diet rich with a variety of fermented foods. Fermented foods like yogurt, tempeh, sauerkraut, and kombucha contain a healthy blend of beneficial microbes and are a safe, natural way to promote healthy gut bacteria.

Consume high-fiber natural prebiotics and daily. Prebiotics are types of dietary fiber that help to feed the good bacteria in the guts. A few rich natural sources of prebiotics are raw garlic, onions, dandelion greens, jicama and bananas.

Consider a probiotic supplement. Probiotic supplements contain the live bacteria and yeasts that are beneficial for a healthy gut. The best sources of probiotics are natural, fermented foods, but if you feel you aren’t getting enough probiotics, or especially after a course of antibiotics, taking a probiotic supplement — especially one that also provides prebiotics — can help to repopulate good bacteria and promote a healthy, balanced gut.

Can Probiotics Protect Against Stress?

Jun 18 by Ewcopywriting Leave a Comment

A new study adds to growing evidence confirming that probiotics can protect against stress. Researchers are studying the application of a type of good bacteria that, if successful in human trials, may result in a probiotic-based immunization to battle mood disorders such as anxiety, depression and posttraumatic stress disorder.

The Complex Link Between Gut Health and Mental Health

Over time, researchers have continued to focus their efforts on investigating the complex link between the brain and gut bacteria. In numerous studies, associations have been made between the trillions of bacteria within our digestive tracts and everything from metabolic function to mood regulation. Each new study adds to supporting evidence that our gut balance and mental health are integrally linked in a highly codependent relationship.

One study uncovered that a lack of gut bacteria altered areas of the brain associated with anxiety and depression. According to another study, disruption of gut microbial balance and the gut-brain axis has been shown to cause depression. Similarly, earlier research highlighted the fact that early life stresses altered the gut bacteria in a way that increased the risk of anxiety later in life.

The link between our guts and brains is also a two-way relationship. While a lack of, or imbalance of, beneficial bacteria in the gut can increase stress, neuroinflammation, and possibly lead to mood disorders, increasing evidence has shown that stress also bears direct, harmful impacts upon gut bacteria balance.

Given all the evidence supporting this association between our emotional wellbeing and gut bacteria, scientists are investigating methods of adjusting gut bacteria in an effort to protect us from the effects of stress.

Mycobacterium Vaccae: Probiotics Protect Against Stress

In this newest study on gut bacteria, researchers from the University of Colorado at Boulder have built upon previous research investigating the soil-based bacterium, Mycobacterium vaccae, in which it was found that mice that were inoculated with the bacteria experienced less inflammation and presented fewer symptoms of anxiety.

In their most recent work, the research team wanted to delve deeper into this good bacteria to uncover exactly how Mycobacterium vaccae affects the brain. In order to do so, researchers injected male rats with the beneficial bacteria once a week for three weeks and took measurements of the proteins in the brain. Two major findings stood out:

The team discovered that a week after the last treatment, the inoculated rats possessed significantly higher levels of a particular anti-inflammatory protein referred to as interleukin-4 in the hippocampal region of the brain. The hippocampus plays a key role in learning and memory. An integral part of the limbic system, one of the roles of the hippocampus is the regulation of anxiety and fear responses.
In addition to increasing anti-inflammatory proteins, the researchers found that when the inoculated rats were placed into a stressful situation, the Mycobacterium vaccae bacteria decreased levels of HMGB1, a stress-induced protein that sensitizes the brain to inflammation, and increased levels of CD200R1, a receptor that preserves the anti-inflammatory state of the brain’s immune cells.

“We found that in rodents this particular bacterium, Mycobacterium vaccae, actually shifts the environment in the brain toward an anti-inflammatory state. If you could do that in people, it could have broad implications for a number of neuroinflammatory diseases,” Dr. Matthew Frank, lead author of the study and senior research associate in the Department of Psychology and Neuroscience at CU Boulder, said in a statement.

Stress-related mood disorders such as anxiety, depression, and PTSD affects one out of every four people at least once in their lives. Strong supporting evidence suggests that these stress-related disorders are at least partially caused by inflammation. “There is a robust literature that shows if you induce an inflammatory immune response in people, they quickly show signs of depression and anxiety. Just think about how you feel when you get the flu,” added Dr. Frank.

Senior study author Christopher A. Lowry, Ph.D., associate professor of integrative physiology at CU Boulder, has been studying Mycobacterium vaccae for 17 years. He explains that their findings help further illuminate the link between probiotics and mood disorders, exhibiting that probiotics help protect against stress. According to Dr. Lowry, “if you look at the field of probiotics generally, they have been shown to have strong effects in the domains of cognitive function, anxiety and fear. This paper helps make sense of that by suggesting that these beneficial microbes, or signals derived from these microbes, somehow make their way to the hippocampus, inducing an anti-inflammatory state.”

While the Mycobacterium vaccae injections have yet to see human trials, the team is hopeful that a similar method of treatment will soon be available to those at risk of developing these inflammation-induced mood disorders. “More research is necessary, but it’s possible that other strains of beneficial bacteria or probiotics may have a similar effect on the brain,” said Dr. Lowry.

Their findings have been published in the journal Brain, Behavior, and Immunity.

The Latest Breakthroughs in Gut Bacteria Research

Jun 14 by Ewcopywriting Leave a Comment

From brain function to metabolic function, the mountains of gut bacteria research over the past few years have only just begun to reveal how the trillions of microorganisms that reside in our guts impact our health. Here’s a roundup of some of the most recent research into our gastrointestinal microbiota and its implications on health.

New Insights Into Gut Bacteria’s Role in Neurological Conditions

Scientists are working to form a better understanding of how the connection between our gut and brain affects the central nervous system. Previous studies have highlighted the fact that the gut microbiota in patients with multiple sclerosis (MS) differs from the bacteria found in those without multiple sclerosis. Researchers from Brigham and Women’s Hospital have been focusing their efforts on exploring the gut-brain connection to better understand this link to multiple sclerosis. In their most recent work, the Brigham team investigated interactions between gut microbes and two particular types of glial cells, astrocytes and microglia, known to play major roles in the central nervous system.

While other studies in the field have explored how byproducts from the microorganisms living in the gut may cause brain inflammation, the team’s newest study is the first to examine how microbial byproducts may prevent inflammation. In their research, they discovered that when the microbes in the gut process tryptophan, an amino acid that is commonly associated with turkey, they produce compounds that are able to cross the blood-brain barrier and activate an anti-inflammatory pathway that restricts neurodegeneration.

The pathway in question has also been associated with both Alzheimer’s disease and glioblastoma. The team believes their research may be useful in understanding other neurologic conditions outside of multiple sclerosis.

According to Francisco Quintana, Ph.D., Associate Professor of Neurology at Harvard and one of the co-authors of the study, “it is likely the mechanisms we’ve uncovered are relevant for other neurologic diseases in addition to multiple sclerosis. These insights could guide us toward new therapies for MS and other diseases.”

The study has been published in the journal Nature. The team plans to delve deeper into the gut’s connection to neurologic conditions. Their findings may one day help guide future therapies for those suffering from neurologic disorders such as multiple sclerosis and Parkinson’s disease.

“These findings provide a clear understanding of how the gut impacts central nervous system resident cells in the brain. Now that we have an idea of the players involved, we can begin to go after them to develop new therapies,” said Dr. Quintana.

Microorganisms in the Gut Trigger Antitumor Response in the Liver

While other studies suggest that the gastrointestinal microbiota influences immune response to cancer, it has not been understood if or how this occurs in the liver. Liver cancer is one of the topmost causes of cancer-related deaths in the world. According to the American Cancer Society, in 2018 alone, over 40 thousand Americans will be diagnosed, and around 30 thousand will die from some form of liver cancer. In a recent study led by scientists from National Cancer Institute Center for Cancer Research (NCI CCR) and published in the journal Science, researchers sought to better understand the relationship between gut flora, liver cancer and the body’s immune response.

The researchers discovered that when they used an antibiotic cocktail to essentially wipe out the gut microbiota, tumors in the liver were fewer and smaller, and there was a reduction of other cancers spreading to the liver.

According to study lead Tim Greten, M.D., “what we found using different tumor models is that if you treat mice with antibiotics and thereby deplete certain bacteria, you can change the composition of immune cells of the liver, affecting tumor growth in the liver. This is a great example of how what we learn from basic research can give us insight into cancer and possible treatments.”

The team investigated the immune cells in the liver to understand the underlying mechanisms behind the tumor suppression. In their research, the team demonstrated that a particular species of bacteria, Clostridium scindens, modified bile acids so that they would signal the liver to produce the CXCL16 chemokine. These signaling proteins stimulate the production of “natural killer T” (NKT) cells, which surveil the liver, reducing the growth of both primary and metastatic liver cancers. The team’s findings provide a better understanding as to the mechanisms that can lead to the development of liver cancer as well as the therapeutic approaches that may be used to treat them.

Gastrointestinal Flora Regulates Fat Stores

Obesity is becoming a growing epidemic and is the leading cause of potentially fatal health conditions like heart disease, stroke and some cancers. A new study led by scientists at King’s College London and published in the journal Nature examined just how the gut processes and stores fat throughout the body. Their findings suggest that putting on pounds is the result of diet and environment rather than genetics.

According to lead investigator Dr. Cristina Menni, “this study has really accelerated our understanding of the interplay between what we eat, the way it is processed in the gut, and the development of fat in the body, but also immunity and inflammation. We have been able to get a snapshot of both the health of the body and the complex processes taking place in the gut.”

In order to better understand how the underlying processes that occur in the gut affect fat processing and distribution, researchers analyzed the fecal metabolome in twin pairs. Their analysis revealed that the gut’s chemical processes were impacted more so by environmental factors such as diet than they were influenced by genetics.

“This new knowledge means we can alter the gut environment and confront the challenge of obesity from a new angle that is related to modifiable factors such as diet and the microbes in the gut. This is exciting, because unlike our genes and our innate risk to develop fat around the belly, the gut microbes can be modified with probiotics, with drugs or with high fiber diets,” said the study’s first author, Dr. Jonas Zierer.

Using the derived data, the researchers compiled a cross-reference of which bacteria were linked with what metabolites, creating a valuable resource that will help future researchers better understand how gut bacteria influences health.

Head of the research group, Professor Tim Spector said, “knowing that they are largely controlled by what we eat rather than our genes is great news, and opens up many ways to use food as medicine. In the future, these chemicals could even be used in smart toilets or as smart toilet paper.”