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Tag: microbiomes

Are Antibiotics Truly Good?

Antibiotics are also known as antibacterials. They can destroy or slow down the growth of bacteria in the body. They’re used to fight against certain infections that attack the immune system. Although the use of antibiotics can save a person’s life, the use of them can have repercussions. Most gut bacteria can recover quickly from the use of antibiotics, however there can be long-lasting effects. The changes it makes isn’t necessarily harmful, but that isn’t always the case. 


The gut microbiome, has roughly 10 trillion to 100 trillion bacteria and other microorganisms that live in the digestive tract, contributes to health by synthesizing vitamins, metabolizing drugs and fighting pathogens. Anything that disrupts the balance of microorganisms, such as antibiotics, which can kill both “good” and “bad” bacteria, has the potential to cause disease.” 

Research done in a 2016 study shows that being exposed to antibiotics as an infant can alter the gut microbiome in a baby and “weaken the immune response for years to come.” The duration of breastfeeding reduces the frequency of infections, and the risk of being overweight. Conclusions of the study conveyed antibiotic use in a child during the breastfeeding period could weaken the beneficial effects of long term breastfeeding. In addition, the results suggest that intestinal microbiota is affected by the long term metabolic benefits breastfeeding has. 

Antibiotics are the most common type of medicine prescribed to young children in the Western world. As mentioned previously, antibiotics can dramatically alter the gut microbial composition. Research shows, “…the gut microbiota plays crucial roles in immunity, metabolism and endocrinology, the effects of antibiotics on the microbiota may lead to further health complications.” Exposure to environmental microorganisms and parasites is important for healthy development and maintenance of the immune system. In Western countries contact with microorganisms has significantly decreased over the recent decades. “ As antibiotics are a factor that reduces exposure to microorganisms and disrupts the body’s natural microbiota, this… may help explain the observed effects of antibiotics on the immune system.”

“Since infancy is a crucial time for microbial establishment, it is necessary to evaluate the influence of antibiotics given quite liberally during this period. Antibiotic treatment given to both infants and toddlers has already been shown to strongly affect microbiome composition. In an attempt to understand the effects of antibiotics on the microbiome, both human reports and experiments in animal models have been employed”.

Although, antibiotics are a powerful source of medication that can fight off infections and save lives when used properly, it is essential to not overuse or become too reliant on them. Overuse contributes to the resistance to fighting bacterial infections, and hurts the body’s natural microbiota.


Can your bacteria reveal your age?

There are billions of bacteria all in, around, and all over you. They prevent diseases, regulate digestion, and everything in between. Researcher Alex Zhavoronkov and his colleagues at InSilico Medicine in Maryland c study and examine whether their predictions that “microbiomes are aging clocks” were true.

To start their study, Alex and his team gathered 3600 samples of gut bacteria from 1165 healthy individuals from around the world, ranging from three age samples. A third of the participants were aged 20 to 39, another third were aged 40 to 59, and the last third were from people aged 60 to 90. They then used machine learning. This means they trained a computer program on “95 different species of bacteria from 90% of the samples, along with the ages of the people they had come from. Then, they asked the algorithm to predict the ages of the people who provided the remaining 10%”. Their program ended up being successful in that 39 bacteria of the 95 were successful in predicting someone’s age within four years.

When researching the certain biomes, Eubacterium hallii-which is important for intestines and metabolisms-became more abundant with age. They also noticed bacteria like Bacteroides vulgatus decreased with age. Alex and his team predict that the different bacteria found may help in detecting peoples’ age.

If validated, the “microbiome aging clock” they created can have many positive effects. It could be used to compare healthy people with those who have diseases. It can test how fast someone is aging and test if any antibiotics, probiotics, diet, or alcohol affect aging. It could help test new treatments or medicine and see if it would have any effect on the aging process. However, challenges may arise. One may include distinguishing whether the different microbes come from age or come from “markedly different populations”. Researcher Robin Knight states, “ it’s also not known whether changes in the microbiome cause people to age more rapidly, or whether the changes are simply a side effect of aging”. It is not yet guaranteed how the aging-clock machine will turn out but if it ends up being successful, many would consider for it to be life-changing.  

Can Bacteria in Your Gut Cause Obesity?

Bacteria in your gut, aka gut microbiota, is made up of tens of trillions of microorganism, including 1000 different species of known bacteria. Although scientists are currently not incredibly knowledgeable on gut microbiota, an increasing amount of research has shown that it is plays a significant role in our health.

In a recent study at Lund University in Sweden, researchers have found correlation between gut bacteria and obesity. The purpose of the study was to identify metabolites in the blood that can be linked to obesity and see if they affect the composition of the gut microbiota in stool samples. The researchers studied blood plasma and stool samples from 674 participants and found 19 different metabolites that could be linked to the person’s BMI. Their data showed that Glutamine and BCAA (branched-chain and aromatic amino acids) had the strongest connection to obesity and that four different intestinal bacteria, Blautia, Dorea, Ruminococcus, and SHA98, were linked to the obesity related metabolites. Glutamine, “the strongest risk factor in the study”, has been linked with obesity in previous studies as well. Marju Orho-Melander, professor of genetic epidemiology at Lund University, summed up the study by stating, “The differences in BMI were largely explained by the differences in the levels of glutamate and BCAA. This indicates that the metabolites and gut bacteria interact, rather than being independent of each other.” Therefore, the metabolites they found are potential mediators between gut microbiota and obesity, and may be consequential in ultimately preventing obesity.

Microbiomes… an Athlete’s Key to Success!

For years, scientists have been trying to see what makes a professional athlete different from someone who didn’t quite make the cut. Is there something that professional and elite athletes have that other athletes or inactive individuals don’t? Is it possible to give a mediocre athlete a supplement to improve their performance? Dr. Jonathan Schieman and George Church from the Wyss Institute at Harvard University believe the answer is yes, and they think they’ve found the answer, microbiomes.

Dr. Schieman and his team conducted thorough research on NBA players, marathoners, and Olympic rowers to see if there was a common microbiome that these high-level athletes all shared that sedentary individuals did not. After immense amounts of testing and making sure the proper controls were in place to avoid confounding, and lurking variables, Schieman and his team were able to find one particular organism that was elevated in the guts of athletes’ bodies more than sedentary individuals.

Schieman and his team were able to isolate a particularly abundant organism in athletes that feeds off lactic acid. Lactic acid is a naturally occurring chemical compound that generates during particularly intense and strenuous muscle exercise. Thus, the researchers believe that the organism they isolated has a particularly important effect on making athletes stronger. In addition, the researchers have recently conducted a new study on rugby players and found that rugby players have more of this organism in their body as well as a more diverse range of microbiomes than a sedentary individual.

The microbiome space is particularly new, so one cannot conclude that these findings will be significant to athletes in the future, a realization that Schieman has come to terms with. However, if Schieman and Church find more conclusive and concrete evidence that these, and other, organisms can yield a much better athlete, the sports world could change forever.

What do you think? Can microbiomes be used to make more elite athletes? Only time will tell.


The research is from Jonathan Schieman and George Church from the Wyss Institute at Harvard University. A comprehensive scientific journal entry has not been released to the public due to intellectual property concerns, as the findings are part of a privately-owned company.


Rotavirus Vaccine Leads to Important Human Microbiome Experiment

     The journal Cell Host & Microbe recently published Vanessa Harris’s and her team’s (scientists from the Netherlands) research regarding a rotavirus vaccine. Over 200,000 children each year die from rotavirus. It is the prominent cause of diarrheal death in children. Therefore, this line of research is essential to help ensure the global health of all people, especially children.

      Harris’s study consisted of sixty-three, healthy male adults. They were randomly assigned one of three possible arms (branches of types of antibiotics): a broad spectrum (with vancomycin/ciprofloxacin/metronidazole treatments), a narrow-spectrum (with a vancomycin treatment) or the control with no vaccine. After this treatment, the results of the antibodies were tested by the subjects’ viral shedding. The three treatment arms led to similar antibody levels although there was a small increase in viral shedding with the narrow-spectrum antibiotic. Most importantly there was an overall difference in between the antibiotic-treated groups compared to the control arm, with the antibiotic treatments resulting in higher viral shedding. Their results showed an impact of antibiotics on microbiomes reaction to the vaccine.

      The research team also worked with children in Ghana and Pakistan which found a correlation between immunity to the rotavirus vaccine and the presence of a specific, intestinal bacteria. A vancomycin arm was added to attempt to recreate similar results to the earlier study with the adult men. Because rotavirus is a childhood disease, the main outcome of this second half of the study was that further, more detailed and specific research is necessary.

        I believe that the scientists are correct in saying that more research is necessary in order to support any large conclusion, yet it seems to me that bacteria can clearly alter microbiomes reaction to rotavirus vaccine. In my opinion, whether that is a mostly positive or negative effect must be the next step in the research in order to use this information to help children in developing countries like Ghana. Most important, the fact that “…[Harris’s] team believes that understanding that triangulation between bacteria, virus, and the human immune system has the potential for vaccinology and can lead to important uses of the microbiome”, should be the driving factor behind research into human microbiomes.

What We Can’t See Is Just As Important As What We Can!

Taken by Ron Lute

Taken by Ron Lute

Many students of biology know that life comes in all shapes and sizes, and even though we can’t see some organisms, they are most certainly present.  If you don’t know this, and you are a biology student, you might want to go back and read the first chapter of your textbooks to learn a big chunk of information that will come around in either next week’s test or your midterm.  For now, you’ve already come this far, so you can just learn the basics later.

As it turns out, some of those little organisms, located just under the soil’s surface,  are vital to the health and safety of the the plant-life they surround.  In an effort to raise awareness of the many effects a microbiome can have on plant performance, Marnie Rout (University of North Texas Health Science Center) and Darlene Southworth (Southern Oregon University) brought together a series of works by different authors on the subject, all placed in a special section of the American Journal of Botany called “Rhizosphere Interactions: The Root Microbiome.”  As a basic understanding of the concept, the rhizosphere is the layer of soil around a plant root.  It contains microbes that affect the plant on basically every scale, from the genes to the ecosystem.  It’s important to note that the microbiome works through the rhizosphere, effectively turning this “metabolically diverse” collection of microbes into a supply source should the plant need anything.  Interestingly enough, the rhizosphere also can act as a type of self-defense grid, similar to how human microbiomes function, where in some cases plants have been known to shed their root’s outer cell layers into the rhizosphere in order to form a “layer of immunity” to the plant.

Perhaps, one day in the future, these microbiomes can offer different types of bacteria that can be used for “crop production… in areas likely to be affected by global climate changes.”  What do you think we still have to learn about microbiomes before uses like this are possible?  Do any of you know someone currently researching in this field?  Are you students who didn’t know that there were organisms that you couldn’t see ever going to look at your textbooks?



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