Is there something unique about the centenarian gut microbiome?
Discoveries from a recent study shed light on the fascinating world of centenarians and their exceptional resistance to age-related ailments. Delving into the unique microbiome of individuals who live to be 100 or more, researchers have uncovered a potential shield against bacterial infections, including those caused by stubborn multidrug-resistant strains.
In this groundbreaking exploration led by a collaborative team from Keio University School of Medicine in Japan and the Broad Institute of MIT and Harvard, 160 Japanese centenarians became the focus. With an average age of 107, these remarkable individuals exhibited higher levels of specific bacterial species that produce secondary bile acids. These acids, generated by microbes in the colon, play a crucial role in safeguarding the intestines from harmful pathogens while regulating the body’s immune responses.
Upon treating laboratory-cultivated infection-causing bacteria with the identified secondary bile acids, particularly one called isoalloLCA, the researchers witnessed a remarkable inhibition of the growth of Clostridioides difficile. This antibiotic-resistant bacterium, notorious for causing severe diarrhea and gut inflammation, faced a potent challenge from isoalloLCA. The study also found that isoalloLCA displayed effectiveness against various other gram-positive pathogens, suggesting its potential in maintaining a healthy microbial balance in the gut.
Damian Plichta, a computational scientist at the Broad and co-first author of the study, emphasized the significance of this ecological interaction between the host and bacteria. He expressed optimism about the gut microbiome’s potential in health maintenance.
While the study opens up exciting possibilities, the researchers emphasize the need for larger and longer-term studies across diverse regions to establish a causal link between longevity and bile acids. In the interim, the identified bacteria offer a promising avenue for exploring how manipulating bile acids could treat infections caused by antibiotic-resistant bacteria.
Ramnik Xavier, co-corresponding author of the study and a core institute member at the Broad, highlighted the collaborative nature of the work and its potential implications. He underlined the importance of future studies focusing on microbial enzymes and metabolites as potential starting points for therapeutics.
This groundbreaking research, supported by the MIT Center for Microbiome Informatics & Therapeutics (CMIT), showcases the role of the gut microbiome as a key player in the quest for healthy aging. The published findings in Nature on July 29, 2021, provide a valuable glimpse into the intriguing connection between centenarians, their unique microbiome, and potential avenues for therapeutic exploration.