Skip to content

I mentioned these studies earlier in July, but this write-up (from Sept. 17, 2014) gives the reader some new information. From Gut Microbiota Watch:

Studies uncover 500 “hidden” microbes in the gut

Over the last few years, scientists have found that the microbes hosted in the digestive tract (the gut microbiota or gut flora) perform key functions for health. Digestion, immunity and even mental health are extremely dependent on tasks carried out by the gut bacteria.

Now, two studies have found that the human gut hosts five hundred species of microbes – and seven million microbial genes – that were unknown until now. The proportion of the gut flora that had been hidden until now may hold essential information on the origin of a range of diseases (IBD and metabolic syndrome, among others), as well as the clues on how to cure them.

The two studies were published in Nature Biotechnology in July, and come from the efforts of the MetaHIT(METAgenomics of the Human Intestinal Tract) project, a European consortium working to explore the composition of human gut microbiota.

The first of the two studies focuses on expanding the catalogue of genes that belong to microbes of the gut flora....As a result, the catalogue has increased to 10 million genes. The next step for the scientists is to find what these genes do, in order to have a better understanding of the functions performed by the microbiota.

The second of the two studies pursues an even more ambitious goal: identifying new organisms in the microbiota, rather than identifying new genes....By applying this method, the authors have found 500 species whose existence in the microbiota was previously unknown.

Interestingly, some of the subjects analysed in the study had very few of these new species. By checking who these individuals were, the authors found that they all had Crohn’s disease, ulcerative colitis, or metabolic syndrome with an inflammatory component. These findings suggest that there is a correlation between suffering from these diseases and having less diversity in these unknown species. “These species, unknown until now, will possibly make the difference between healthy and unhealthy people”, said Guarner.

This information may open the door to new strategies aimed at recovering the presence of these species through nutritional intervention. In particular, providing patients with probiotics or prebiotics,  that may help to balance their microbiota.

This article summarizes some of the same things I've been posting here. From NY Times:

We Are Our Bacteria

We may think of ourselves as just human, but we’re really a mass of microorganisms housed in a human shell. Every person alive is host to about 100 trillion bacteria cells. They outnumber human cells 10 to one and account for 99.9 percent of the unique genes in the body.

Our collection of microbiota, known as the microbiome, is the human equivalent of an environmental ecosystem. Although the bacteria together weigh a mere three pounds, their composition determines much about how the body functions and, alas, sometimes malfunctions. Like ecosystems the world over, the human microbiome is losing its diversity, to the potential detriment of the health of those it inhabits.

Dr. Martin J. Blaser, a specialist in infectious diseases at the New York University School of Medicine and the director of the Human Microbiome Program, has studied the role of bacteria in disease for more than three decades. In his new book, “Missing Microbes,"Dr. Blaser links the declining variety within the microbiome to our increased susceptibility to serious, often chronic conditions,  from allergies and celiac disease to Type 1 diabetes and obesity. He and others primarily blame antibiotics for the connection.

The damaging effect of antibiotics on microbial diversity starts early, Dr. Blaser said. The average American child is given nearly three courses of antibiotics in the first two years of life, and eight more  during the next eight years. Even a short course of antibiotics like the widely prescribed  Z-pack (azithromycin, taken for five days), can result in long-term shifts in the body’s microbial environment.

But antibiotics are not the only way the balance within us can be disrupted. Cesarean deliveries, which  have soared  in recent decades, encourage the growth of microbes from the mother’s skin, instead of from the birth canal, in the baby’s gut, Dr. Blaser said in an interview.

This change in microbiota can reshape an infant’s metabolism and immune system. A recent review of 15 studies involving 163,796 births found that, compared with  babies delivered vaginally, those born by cesarean section were 26 percent more likely to be overweight and 22 percent more likely to be obese as adults. 

The placenta has a microbiome of its own, researchers have discovered, which may also contribute to the infant’s gut health and help mitigate the microbial losses caused by cesarean sections.

Further evidence of a link to obesity comes from farm animals. About three-fourths of the antibiotics sold in the United States are used  in  livestock. These  antibiotics change the animals’ microbiota, hastening their growth. When mice are given the same  antibiotics used on livestock, the metabolism of their liver changes, stimulating an increase in body fat, Dr. Blaser said.

Even more serious is  the increasing number of serious disorders now linked to a distortion in the microbial balance in the human gut. They include several that are becoming more common in developed countries: gastrointestinal ailments like Crohn’s disease, ulcerative colitis and celiac disease; cardiovascular disease; nonalcoholic fatty liver disease; digestive disorders like chronic reflux; autoimmune diseases like multiple sclerosis and rheumatoid arthritis; and asthma and allergies.

Study after study is suggesting that exposure to lots of diverse bacteria and microorganisms (think farms with animals) is healthy for the developing immune system. From Science Daily:

Growing up on livestock farm halves risk of inflammatory bowel diseases

New research conducted at Aarhus University has revealed that people who have grown up on a farm with livestock are only half as likely as their urban counterparts to develop the most common inflammatory bowel diseases: ulcerative colitis and Crohn's disease

"It is extremely exciting that we can now see that not only allergic diseases, but also more classic inflammatory diseases appear to depend on the environment we are exposed to early in our lives," relates Vivi Schlünssen, Associate Professor in Public Health at Aarhus University.

"We know that development of the immune system is finalized in the first years of our lives, and we suspect that environmental influences may have a crucial effect on this development. The place where you grow up may therefore influence your risk of developing an inflammatory bowel disease later in life."

However, the researchers have a theory that the body may be dependent on exposure to a wide variety of microorganisms to develop a healthy immune system -- in the same way as has been established in studies on allergies and asthma.

"We know that the difference in the microbial environment between city and country has increased over the past century, and that we are exposed to far fewer different bacteria in urban environments today than we were previously. This may in part explain our findings," says Signe Timm.

Over the past 40-50 years, incidence of the diseases has sky-rocketed in Northern Europe -- including Denmark -- as well as in Canada and the United States, although they are still relatively rare in developing countries.

Another article stating that the future is feces in treating a number of diseases. From Pacific Standard:

Medicine’s Dirty Secret: Fecal Transplants Are the Next Big Thing in Health Care

POO IS A DECIDEDLY IMPERFECT delivery vehicle for a medical therapy. It’s messy. It stinks. It’s inconsistent, not to mention a regulatory nightmare. But it can be incredibly potent. A classic study of nine healthy British volunteers found that bacteria accounted for more than half of the mass of their fecal solids. That astonishing concentration of microorganisms, both living and dead, makes sense when you consider that the microbial colonists inhabiting our gastrointestinal tract outnumber our own cells roughly three to one, on recent estimates.

In the ideal conditions of the human gut, a thriving ecosystem of 1,000 or more bacterial species that rivals the complexity of a rainforest has co-evolved with us. This microscopic jungle is constantly adapting in response to our diet, antibiotic use and other environmental influences. As the science has progressed, researchers are now comparing the entire collection of microbial inhabitants of the human gut, our microbiome, to a “hidden metabolic organ.” Scientists have linked disruptions to this organ, a condition known as dysbiosis, to everything from inflammatory bowel disease and high blood pressure to diabetes and obesity.

Viewed in this light, a fecal microbiota transplant is nothing more than an attempt to reseed an intestinal tract, often after antibiotics have killed off the native flora that might have kept invasive species at bay. No other medical therapy can claim such a high cure rate for the infection widely known as C. diff.

Some doctors have likened the recoveries of desperately ill patients to those seen with anti-HIV protease inhibitors in the mid-1990s. After the Mayo Clinic in Scottsdale, Arizona, performed its first fecal microbiota transplant in 2011, a patient who had been bed-ridden for weeks left the hospital 24 hours later. And in 2013, researchers in the Netherlands halted a landmark C. diff. clinical trial early for ethical reasons when they saw that the overall cure rate of 94 percent with donor feces had far outpaced the 31 percent cured with the antibiotic vancomycin.

Yet few other interventions elicit such disgust, revulsion, and ridicule. Chronicling a potential advance by a team of Canadian scientists, one newspaper account warned readers: “Hold your nose and don’t spit out your coffee.” In 2013, the founder of a patient advocacy blog called The Power of Poop wrote an open letter to 13 gastroenterology associations detailing the story of a Kentucky man who contracted an acute case of C. diff. Despite his family’s pleas, his doctor dismissed the idea of a fecal transplant as “quackery.” The man died the next day.

Although most providers haven’t published their overall success rates, their self-reported results are surprisingly similar, and consistent with what published reports there are. Khoruts says he has achieved a success rate of about 90 percent after one infusion, 99 percent after two. “In medicine, it’s pretty startling to have therapy that’s that effective for the most refractory patients with that condition,” he says. Colleen Kelly, a gastroenterologist with the Women’s Medicine Collaborative in Providence, Rhode Island, has performed the procedure on 130 patients with recurrent C. diff., with a success rate of about 95 percent. Most of the transplants have taken after just one attempt.

For a relatively simple bacterial infection, Petrof says, the potential remedy may be fairly straightforward. “With recurrent C. diff. what you’ve done is you’ve basically torched the forest,” she says. Nearly everything has been killed off by the antibiotics, leaving very low bacterial diversity. “So the C. diff. can just take root and grow.” Adding back almost any other flora—the equivalent of planting seedlings in the dirt—could help the ecosystem keep interloping pathogens at bay.

For more complicated conditions, though, a simple fecal transplant may not be enough, at least with donors from the Western world. One hypothesis suggests that people in lower-income countries might harbor more diverse bacterial populations in their guts than those who have grown up in a more sterile, antibiotic-rich environment. And in fact, a 2012 study found that residents of Venezuela’s Amazonas state and rural Malawi had markedly more diverse gut microbiomes than people living in three U.S. metropolitan areas. Scientists have already raised the idea that a rise in allergies and autoimmunity in industrialized nations may derive from a kind of collective defect of reduced microbial diversity.

“We cannot find people who’ve never been on antibiotics,” Khoruts says of his donors. For complex autoimmune diseases such as ulcerative colitis, fecal transplants may offer only a partial solution. And with some data suggesting that susceptibility may be linked in part to past antibiotic exposure, perhaps no Western donor can provide the microbes needed to fully reseed the gut.

What then? Khoruts says it may be necessary to seek out ancestral microbial communities—the ones all humans hosted before the advent of the antibiotic era—within people in Africa or the Amazon. “It’s just a disappearing resource,” he says.

By the beginning of April 2014, nearly 30 fecal transplant clinical trials were underway around the world. Roughly half were aimed at C. diff., including two testing the therapy in combination with vancomycin, and another multi-center trial evaluating the effectiveness of fresh versus frozen donor poo.

As the therapy becomes more widely established, via something akin to a “poop pill” or “crapsule,” perhaps the infectious pool of C. diff. patients may start to dwindle. More clinicians, then, might feel emboldened to explore how our bowel flora may affect not only the gastrointestinal system but also the immune and neurological systems. At least a dozen trials are now investigating whether fecal transplants can help treat some form of inflammatory bowel disease, be it Crohn’s disease or ulcerative colitis. Another is looking into Type 2 diabetes, and one is even using lean donors to test fecal transplants on patients with metabolic syndrome. Researchers say it won’t be along before they’re joined by studies investigating whether the therapy might aid diseases like multiple sclerosis and autism.

For those who want to know more, another article form The Pacific Standard:

6 Ways to Transplant Fecal Matter, at Home or at the Hospital

And the following two groups:  The Fecal Transplant Foundation

The Power of Poop