Antibiotics have been touted as wonder drugs that have saved countless lives since their discovery in the 1940s, but their widespread use has also had a downside. Antibiotics are indiscriminate killers of both harmful and helpful bacteria, leading to the disruption of the delicate balance of bacteria in the gut microbiome. This disruption can lead to a host of health problems, including obesity, diabetes, and even mental health issues. But what if there were a way to protect the gut microbiome while still taking antibiotics? In this article, we’ll explore new research that has found compounds that can help preserve the gut microbiome and potentially reduce antibiotic-related side effects.
New research presented at the European Congress of Clinical Microbiology & Infectious Diseases has identified antidote drugs that could protect certain gut microbes without interfering with antibiotics’ effectiveness against harmful bacteria. Antibiotics fight bacterial infections, but they can also harm the helpful microbes living in the gut, which can have long-lasting health consequences. The study, conducted by a team from the European Molecular Biology Laboratory in Germany, analyzed the effects of 144 different antibiotics on the abundance of the most common gut bacteria. It offers novel insights into reducing the adverse effects of antibiotic treatment on the gut microbiome. The trillions of microorganisms in the human gut profoundly impact health by aiding digestion, providing nutrients and metabolites, and working with the immune system to fend off harmful bacteria and viruses.
Antibiotics can damage these microbial communities, resulting in an imbalance that can lead to recurrent gastrointestinal problems caused by Clostridioides difficile infections as well as long-term health problems such as obesity, allergies, asthma, and other immunological or inflammatory diseases. Despite this well-known collateral damage, which antibiotics affect which types of bacterial species, and whether these negative side effects can be mitigated, has not been studied systematically because of technical challenges.
The results of the study revealed that the majority of gut bacteria had slightly higher minimal inhibitory concentration (MICs) than disease-causing bacteria, suggesting that at commonly used antibiotic concentrations, most of the tested gut bacteria would not be affected. However, two widely used antibiotic classes, tetracyclines and macrolides, not only stopped healthy bacteria growing at much lower concentrations than those required to stop the growth of disease-causing bacteria, but they also killed more than half of the gut bacterial species they tested, potentially altering the gut microbiome composition for a long time.
To find out more, the researchers systematically analyzed the growth and survival of 27 different bacterial species commonly found in the gut following treatment with 144 different antibiotics. They also assessed the MIC for over 800 of these antibiotic-bacteria combinations. As drugs interact differently across different bacterial species, the researchers investigated whether a second drug could be used to protect the gut microbes. They combined the antibiotics erythromycin (a macrolide) and doxycycline (a tetracycline) with a set of 1,197 pharmaceuticals to identify suitable drugs that would protect two abundant gut bacterial species (Bacteriodes vulgatus and Bacteriodes uniformis) from the antibiotics.
The researchers identified several promising drugs including the anticoagulant dicumarol, the gout medication benzbromarone, and two anti-inflammatory drugs, tolfenamic acid and diflunisal. Importantly, these drugs did not compromise the effectiveness of the antibiotics against disease-causing bacteria. Further experiments showed that these antidote drugs also protected natural bacterial communities derived from human stool samples and in living mice. While promising, further research is needed to identify optimum and personalized combinations of antidote drugs and to exclude any potential long-term effects on the gut microbiome.
In conclusion, the discovery of compounds that can protect our gut microbiome from the damaging effects of antibiotics is an exciting development in the field of microbiology. With antibiotic resistance on the rise, it is critical that we find ways to preserve the delicate balance of bacteria in our gut. These new compounds could potentially revolutionize the way we think about antibiotic use and help us maintain a healthy gut microbiome during and after treatment. As research continues in this direction, we can look forward to a future where antibiotics and our gut microbiome can coexist in harmony.
