Probiotics may help fight the flu

The influenza viruses are the devastating viruses that cause the flu.  They highly communicable and can cause pneumonia, ear infections, sinus infections, asthma and even diabetes.  Basically, they are really nasty bugs that people have been suffering from, and trying to get rid of, for at least the last 2000 years.  One possible treatment, which is now being explored, is the use of probiotics to prevent flu and its virulence.  Scientists in Japan recently tested how one type of probiotic, Bifidobacterium longum, could combat the flu in mice.  They published their results in Microbiology and Immunology.

Mice were divided into two groups, one which received the B. longum for 17 consecutive days in their drinking water, and one which did not.  On day 14 of the study all the mice were infected with flu via injection.  The researchers then monitored all of the mice to see the effect of the probiotics.  Surprisingly, the mice which received the probiotics had improved clinical symptoms as compared to those that did not.  For example, the mortality rate dropped from 70% to 35% after 12 days in those mice that had been given probiotics.  In addition, the probiotics seemed to help with breathing and general activity as well as kept mice from losing as much weight as the control mice.  Beyond this, the probiotics appeared to decrease the proliferation of the influenza in the respiratory tract, which resulted in a suppression of overall inflammation as compared to the mice without probiotics.  Finally the researchers presented evidence for several possible pathways by which the probiotics were helping the mice.

This study is fascinating in that it shows a simple, yet powerful tool to alleviate the flu in mice.  It also begs for a follow-up study to see if the same type of probiotic response would be observed in mice infected with rhinoviruses, the cause of the common cold.  While we here at the AMI encourage everyone to get vaccinated for the flu, if for whatever reason you cannot, perhaps consider eating a bit more yogurt this winter.

The continent you were born on may increase your risk for diabetes

Researchers are finding that imbalances in the gut microbiome can be linked to many diseases, especially autoimmune diseases like type I diabetes. A study called The Environmental Determinants of Diabetes in the Young (TEDDY) was formed to test what environmental factors can trigger type I diabetes in young children that are genetically at-risk for the disease.

In a study published by Diabetes Care, researchers working on the TEDDY study collected fecal samples from infants,at centers located in Finland, Sweden, Germany, Colorado, Washington state, and Georgia/Florida. The samples were collected monthly, and were tested on factors including age, sex, delivery method, early feeding, and later diet.

 The results of the study showed that young type I diabetes at-risk children have specific patterns of microbiome colonization per study site. In other words, there was a significant geographical association with diversity of gut bacteria. Finland, which has the highest incidence of type I diabetes, had  relatively low microbiome diversity and significantly higher abundances of Bacteroides and Veillonella and a lower abundance of traditional infant microbiome bacteria like  Bifidobacterium.  Interestingly, while there were intracontinental similarities between microbiomes, geography did not appear to be a dominant factor.  For example, Swedish microbiomes were more similar to those from Washington state than from Finaland..

 These results are among the first published from the TEDDY study, from which there should be significant discoveries.  For now, it appears the microbiome may play a role in the incidence of diabetes, but as is always the case, until an actual mechanism is proven it is too early to draw further conclusions.

Promoting your dog’s microbiome through functional food

Dogs are man’s best friend, but did you know that they can suffer from digestive diseases and inflammatory bowel diseases too?  A new study published in the British Journal of Nutrition aimed to investigate how dog foods could be ‘functionalized’ by the addition of potato fiber.  This prebiotic promoted the production of many important molecules and shifted the microbiome in ways that may be critical to gut health.

In the study, numerous dogs had their feces sampled for their microbiome in addition to metabolites.  A control group was fed a normal diet and an experimental group was fed the normal diet with the different amounts of potato fiber.  All of the dogs’ microbiomes were richest in Firmicutes, regardless of diet.  However, dogs given potato fiber had an increase in Firmicute abundance, as well as Bifidobacterium spp. and Lactobacillus spp.   Both Bifodobacterium and Lactobacillus are common probiotics that are shown to promote gut health in humans.  In addition, one particular bacterium, Faecalibacterium prausnitzii, was shown to proliferate after the potato fiber was added to the diet.  This bacterium has also been related to decreases in IBD in humans.  Finally, the dogs that ate potato fiber had an increase in butyrate, short chained fatty acids (SCFAs), and an overall decrease feces pH.  Each of these has been implicated with lower incidence of IBD.

This study was one of the first to investigate prebiotics in dog food.  The simple addition of potato fiber, a complex carbohydrate, had important changes on the microbiome, including the production of SCFAs which we have blogged about in the past.  Potato fiber may be an easy, inexpensive dog chow additive for all dog owners and lovers to help their pets lead happier, healthier lives.

Reflecting on the microbiome during National Breast Cancer Awareness Month

As you watched the future Hall of Fame quarterback Eli Manning over the past two weeks, you probably noticed NFL players wearing pink for National Breast Cancer Awareness Month. Before this month comes to a close we want to bring your attention to one of our previous posts about the microbiome and breast cancer.  The study showed that post-menopausal women who had a more diverse gut microbiome had a lower risk of getting breast cancer. You can read more about it here.  

We also want to take this time to encourage natural breast feeding, whenever possible, for all new mothers.  A new review article published in Nature Pediatric Research describes the importance of breast milk in creating a healthy infant microbiome.  Breast milk is a complex food that contains bacteria and also supports the growth of bacteria.  The review highlights that when compared to formula, breast feeding leads to more infant gut colonization of Bifidobacterium, Lactobacillus, and Clostridia, and these bacterial strains are linked to the development of a healthy gut and a healthy immune system.  In addition, breast milk leads to a lower infant gut pH, compared to formula, and infant gut pH affects further species colonization.  Breast milk has evolved to support both us and our microbiomes, and no simple formula can substitute for the real thing.  

Every week there are new studies connecting the microbiome to public health and disease areas that may not seem as obvious as others. We know that the microbiome influences diseases and conditions like obesity, inflammatory bowel disease (IBD), diabetes, and necrotizing enterocolitis (NEC), but we are now learning that the microbiome is also connected to diseases and conditions like breast cancer, alcoholism, autism, and depression. While it is important to keep our excitement about the microbiome in check, the AMI is building new resources for the microbiome field because we believe our impact can be vast.  Advancing the field of research as a whole can influence the development of new treatments and therapies for a wide range of diseases. 

More evidence that probiotics help to prevent necrotizing enterocolitis

In an article published by Nature Pediatric Research, researchers investigated the effectiveness of the bacteria Bifidobacterious longum subsp. infantis as a probiotic used to decrease the risk of necrotizing enterocolitis (NEC). NEC, as we have discussed previously in this blog, is a type of bacterial infection in premature babies, which can often be fatal. To study the effectiveness of B. infantis, researchers assigned 50 rat pups into three groups, which were delivered one day premature of term, to be fed by their mothers, fed with formula, or fed with formula supplemented with B. infantis. The pups were also exposed to hypoxia and cold stress. Intestinal tissue was tested for response.

The results of this experiment reinforced the importance of maternal milk, and showed the importance of a probiotic, B. infantis, if formula must be used.  None of the mother fed mice were diagnosed with NEC, while ~80% of formula fed pups were.  By supplementing the probiotic though, less than 40% of the rat pups were diagnosed with NEC, and the severity of NEC was lower in these instances.  Results also suggested that the probiotic decreased the inflammatory immune response of the underdeveloped intestinal mucus layer. The second part of the experiment, involving putting stress on the rat to observe responses, resulted in data that was inconclusive but suggested that stresses such as hypoxia and cold may not significantly alter the microbiome of the intestines.

While the results of the above experiment did not conclude whether outside stress effects the response of the microbiome in premature rat pups, they still show that certain bacteria such as B. infantis can be useful as a probiotic in preventing NEC.