Even if beneficial bacteria remain alive, failure to 'function properly' can lead to obesity and atopy

[Financial News] A study has found that people may develop chronic diseases such as obesity or atopy if beneficial bacteria in the gut remain present but fail to function properly. While previous research focused only on reductions in the 'types and numbers' of gut microbes, the development of new biomedical technologies that also diagnose and treat 'impaired function in bacteria that remain' is expected to gain momentum.
Professor Kim Hee-nam of Korea University's College of Health Sciences proposed a new framework for assessing damage to gut microbes using two measures: 'the loss of bacteria (a quantitative decline)' and 'impaired function in bacteria that remain (qualitative deterioration),' and announced it on the 26th. The research paper was published on the 15th in the international journal Gut Microbes.
Until now, researchers have believed that the 'loss of bacteria'—a gradual decline in the types of gut microbes found in people today—causes chronic diseases such as metabolic disorders and allergies. Professor Kim, however, proposed an additional 'microbial dysfunction hypothesis': even when beneficial bacteria in the gut remain alive and are not destroyed, environmental factors such as antibiotics or diet can cause genetic mutations, leading them to lose their original beneficial functions or even become harmful bacteria.
The research team found, in an analysis of 'Akeomansia,' a representative beneficial bacterium, that mutant strains whose function had been impaired by exposure to antibiotics were much less effective at suppressing obesity than normal strains. Ecological changes were also observed in another beneficial bacterium, 'Pikalribakterium': depending on the gut environment, harmful strains proliferated, worsening symptoms of atopic dermatitis or even affecting offspring.
The study is seen as providing an important basis for developing personalized treatments that restore microbes whose function has declined or suppress harmful functions, moving beyond the conventional approach of simply consuming beneficial bacteria such as lactic acid bacteria to replenish their numbers.
Professor Kim Hee-nam said, "It is difficult to accurately assess gut health using the conventional approach of examining only the composition of bacteria," adding, "A new assessment framework that considers both the disappearance of bacteria and impaired function will help advance strategies for diagnosing, preventing and treating chronic diseases in the future."  

[email protected] Kim Man-gi Reporter