Interest in the gut microbiome has exploded in the past several years and is being recognized for its potential to change for the medical field. Naturally, the first real interest into the microbiome began with research into its effect on the digestive system. As the research unfolded, it became more and more common for people to aid the health of the microbes living inside of them. Probiotics soared in usage. Diets and lifestyle habits changed. Even our reliance on antibiotics has been tested.
Then, Clostridium difficile happened. Lengthy use of powerful antibiotics often resulted in devastation to patients’ gut microbiome. With the normal intestinal flora wiped out, C. diff has a much easier time taking over. And unfortunately, it is both a deadly and highly contagious pathogen that is difficult to kill
This problem required a new solution beyond probiotic usage and dietary changes. Our antibiotic usage was part of the problem. Healthy gut microbes needed to be re-established in the system to outcompete C. diff. Like planting grass to prevent weeds. This process involves fecal transplants from a healthy donor to a sick patient and has become critical in treating C. diff infections.
Although currently limited to treating C. diff. infections, fecal transplants are gaining research interest for applications outside of gut health. From physical to psychological, here are five areas of cutting edge research on the gut microbiome.
Rheumatoid Arthritis is among the most common autoimmune diseases in the world. The obvious course of treatment has been to modify the immune system directly. However, the intestines do interact with the immune system in important and interesting ways- including turning certain immune cells on and off. As gut microbiota research has advanced, studies have come to show differences in the microbe population in RA vs Non-RA patients. Certain species of Lactobacillus tend to be more populous in RA patients. Researchers hope that by using fecal transplants to establish normal gut flora, the immune system can be coaxed into functioning normally.
You are what you eat. And you are what your gut microbes eat. Although obesity is certainly brought on by multiple factors- from environment to genetics- there may be applications for modulating gut flora through fecal transplant. One fascinating study showed certain species of bacteria have been directly correlated with body mass index. Some bacterial species are associated with low BMI, while other species are associated with high BMI. These kinds of findings show potential for fecal transplants to be used as a sort of microbial population control in the fight against obesity. Transfer in leanness-associated bacteria to outcompete obesity causing species.
There is nothing new with using transplants and transfusions to give healthy tissue from donors to sick individuals. From bone marrow and blood transfusions to organ transplants. The recipient’s body is improved by tissue from the donor and gains healthy function. Now the same may be true for blood pressure when receiving fecal transplants. A fascinating study in mice has shown hope for this as a future treatment in humans. The study tested recipient mice with no gut flora, and two donor groups. The donor mice had either high blood pressure or low blood pressure. Following fecal transplant, the blood pressure of the recipient mice began to mimic that of the donor.
This is the area of research where our knowledge of gut microbiomes begins to transcend science and touch on philosophy. It challenges our past notions of intestinal microbes being just a vat of gunk along for the ride. Alcohol dependence is historically thought of as a behavior. An aspect of our psychology. A set of choices that we make. If bacteria can affect this, how separate can we be from our microbes- or are they an integral part of being human. But that is exactly what the science is beginning to show. The precise nature of this microbial influence on alcoholism is still unclear. However, it is clear that alcohol has a dramatic impact on the intestines, leading to changes in the microbial population and mucosal linings. The inflammation caused by alcohol in the gut, is then thought to cause inflammation in the brain. This possibly occurs via pro-inflammatory metabolites traveling through the bloodstream to the brain. Otherwise, the vagus nerve may be sending the signal. Either way, there is evidence to suggest that restoring proper gut microbiota can improve alcohol abuse.
Here we go again. Autism Spectrum Disorder (ASD) seems like a neurological disorder. No ifs, buts, or whens. Its affect on individuals’ psychology and personality is extreme. To believe microbes in the gut have any role in the disorder seems on par with believing aliens are using mind control. However, this area of research stems from the much more grounded data on the prevalence of intestinal issues in the autistic community. When looking for a cause of these digestive ailments, researchers found commonalities in the microbiome of those with Autism. And fecal transplants given to Autistic individuals have shown some astonishing changes. Not just on the GI system, but on the more typical Autism symptoms as well. In fact, when measured on the Chidhood Autism Rating Scale, study participants receiving a fecal transplant from non-autistic individual had a 47% decrease in severity.
The realization of the great importance our gut microbiome is still fairly recent. We can compare it to more established areas of biology (genomics, proteomics, etc.) and get an idea of how things may develop in the future. As of now, we know fairly little, and the clinical applications of fecal transplants is essentially limited to C. diff. infections. As research is progressing, we are seeing how the microbes in our gut can affect our health in totality; including behavioral and psychological aspects of our health. With personalized medicine becoming such a hot topic and mapping personal genomes becoming a reality, we could see similar advances in the microbial world. The mapping of individuals’ microbiomes. The industrial production of healthy gut flora and the manipulation gut microbe populations to treat and cure a whole range of diseases.