Chinese and American scientists have identified a type of gut bacteria that can effectively break down the harmful nicotine found in tobacco.
The study, conducted by Peking University, Zhejiang University, Fudan University, Wenzhou Medical University in China, and the National Institutes of Health in the United States, was published in the journal Nature on October 19.
Initially, the researchers administered nicotine-containing water to 12 laboratory mice, half of which had gut bacteria while the other half did not, to monitor the effects and make comparisons. The results indicated that the mice lacking gut bacteria had significantly higher levels of harmful nicotine in their intestines compared to the other six.
Subsequently, they examined these bacteria and identified a species named Bacteroides xylanisolvens that could efficiently break down nicotine in petri dishes with the help of the NicX enzyme.
Bacteroides xylanisolvens bacteria can break down nicotine, a harmful component in tobacco. (Photo: Doucefleur)
To determine if the bacteria could reduce the severity of non-alcoholic fatty liver disease, the research team fed 12 other mice with gut bacteria a diet high in sugar and cholesterol along with nicotine-containing water for 20 weeks to induce this condition. Some of the mice were also injected with a dose of B. xylanisolvens three times a day into their stomachs. As expected, these mice had only half the nicotine levels in their intestines.
Furthermore, their livers showed less scarring and inflammation compared to the other mice, indicating that Bacteroides xylanisolvens countered the harmful effects of nicotine.
The researchers also analyzed stool samples from 41 smokers with non-alcoholic fatty liver disease and found that those with higher levels of Bacteroides xylanisolvens in their feces had less severe disease conditions.
The lead author of the study, Lulu Sun from the National Institutes of Health, stated that a probiotic formulation containing the NicX enzyme could be developed in the future for human use to reduce nicotine accumulation and prevent fatty liver disease.
However, further research is needed to determine its effectiveness, as “it is very difficult to truly change the human gut microbiome in the long term.” It should also not be seen as a means to continue smoking, noted co-author Frank Gonzalez from the National Institutes of Health.
