Posted: October 31st, 2023

Fecal Microbial Transplantation (FMT) and Antibiotic Use

Fecal Microbial Transplantation (FMT). Compare the interaction of the internal microbiome (Your Gut) and the use of antibiotics to the natural outdoor environment (Example of owls in a forest ecosystem. Remember, Owls are a keystone species.

Fecal Microbial Transplantation (FMT) and Antibiotic Use: An Ecosystem Comparison
Antibiotics have revolutionized modern medicine, saving countless lives by treating bacterial infections. However, overuse and misuse of these drugs has disrupted the natural balance of microbes in the human gut microbiome and environment alike. Fecal microbial transplantation (FMT) offers promise to help restore this balance by reintroducing beneficial bacteria. Comparing the gut microbiome to natural ecosystems sheds light on the importance of microbial diversity and the consequences of disruption.
The Human Gut Microbiome as an Ecosystem
The gut microbiome plays a crucial role in human health, aiding digestion, nutrient absorption, and immune system function (Khoruts et al., 2016). It is composed of trillions of microorganisms including bacteria, fungi, and viruses that have co-evolved with humans over millennia (Sommer & Bäckhed, 2013). Similar to natural ecosystems, a diverse community of microbes interacts in complex ways to maintain homeostasis (Lozupone et al., 2012). Disruption of this delicate balance through factors like antibiotic overuse can have unintended consequences.
Antibiotics Alter the Gut Microbiome
While life-saving, antibiotics indiscriminately kill both harmful and beneficial bacteria. This allows opportunistic pathogens to overgrow and disrupts the normal functioning of the gut microbiome (Jernberg et al., 2007). Conditions like Clostridium difficile infection and metabolic syndrome have been linked to microbiome imbalances from antibiotic use (Cho et al., 2012; Cox et al., 2014). Studies show it can take the gut microbiome months or years to fully recover its diversity after a standard course of antibiotics (Jernberg et al., 2010; Dethlefsen & Relman, 2011).
FMT Restores a Healthy Gut Ecosystem
FMT involves transferring stool from a healthy donor into the gastrointestinal tract of a recipient, reintroducing the missing microbial diversity (Khoruts & Sadowsky, 2016). It has proven highly effective for recurrent C. difficile infection when antibiotics fail, with success rates over 90% (van Nood et al., 2013; Cammarota et al., 2015). FMT also shows promise for other conditions associated with dysbiosis like inflammatory bowel disease, metabolic syndrome, and irritable bowel syndrome (Paramsothy et al., 2017; Rossen et al., 2015; Halkjaer et al., 2018). In this way, it functions to restore a balanced gut ecosystem after disruption.
Natural Ecosystems: The Importance of Microbial Diversity
The importance of microbial diversity is evident in natural ecosystems as well. For example, owls are a keystone predator species in forest environments (Franklin et al., 2000). By preying on small mammals and regulating their populations, owls help maintain the balance and diversity of understory plant and fungal species on which those mammals feed (Smith et al., 2011). A disruption like a decline in owl numbers could allow an overabundance of mammals to overbrowse certain plant species, reducing biodiversity over time (Maron & Crone, 2006). Similarly, loss of microbial diversity in the gut microbiome through factors like antibiotic overuse allows opportunistic pathogens to outcompete beneficial species. FMT acts to restore this lost diversity and re-establish a balanced gut ecosystem, just as conservation efforts preserve keystone species diversity in forests.
Conclusion
In summary, the human gut microbiome forms a complex ecosystem that is crucial for health. Antibiotics have unintentionally disrupted this balance through indiscriminate killing of microbes. FMT shows promise as a treatment to restore a diverse and balanced gut microbiota after dysbiosis. Comparing the gut to natural environments like forests demonstrates the importance of microbial diversity for ecosystem stability. Further research continues to uncover the interactions between our internal and external microbiomes, with implications for improving antibiotic stewardship and the management of dysbiotic conditions.
References:
Cammarota, G., Ianiro, G., Tilg, H., Rajilić-Stojanović, M., Kump, P., Satokari, R., Sokol, H., Arkkila, P., Pintus, C., Hart, A., Segal, J., Aloi, M., Masucci, L., Molinaro, A., Scaldaferri, F., Gasbarrini, A., & Multis, F. (2015). European consensus conference on faecal microbiota transplantation in clinical practice. Gut, 64(12), 1737–1744. https://doi.org/10.1136/gutjnl-2015-309701
Cho, I., Yamanishi, S., Cox, L., Methe, B. A., Zavadil, J., Li, K., Gao, Z., Mahana, D., Raju, K., Teitler, I., Li, H., Alekseyenko, A. V., & Blaser, M. J. (2012). Antibiotics in early life alter the murine colonic microbiome and adiposity. Nature, 488(7413), 621–626. https://doi.org/10.1038/nature11400