Effect of different sweeteners on the oral microbiota and immune system of Sprague Dawley rats

Sucrose, xylose, and saccharin are commonly used beverage additives and long-term consumption of these compounds inevitably affects the oral immune system and the composition of oral microbiomes. In this study, we used 24 Sprague Dawley rats divided into four groups, i.e., sucrose, saccharin, xylose, or pure water treated over an eight week period to evaluate any changes in the composition, community structure, and function of the oral microbiomes. At the end of the treatment period, we collected oral microbiome samples from each animal and subjected them to high-throughput sequencing. We also used ELISA to determine the concentration of salivary immunoglobulin in these rats to reveal the effect of sweetener on the oral immune system. Sequencing results demonstrated that Firmicutes and Proteobacteria, remained the predominant phyla, but we found that the oral microbial diversity of rats drinking sucrose water was significantly higher than that of the other groups. Our results indicate that drinking water supplemented with sweeteners may influence oral immunity as well as the composition, metabolic function, and diversity of the oral microbiota, thereby disrupting the oral microbiome.