Metabarcoding reveals that a non-nutritive sweetener and sucrose yield similar gut microbiota patterns in Wistar rats

Abstract The effects of non-nutritive sweeteners (NNS) on the gut microbiota are an area of increasing research interest due to their potential influence on weight gain, insulin resistance, and inflammation. Studies have shown that mice and rats fed saccharin develop weight gain and metabolic alterations, possibly related to changes in gut microbiota. Here, we hypothesized that chronic exposure to a commercial NNS would change the gut microbiota composition in Wistar rats when compared to sucrose exposure. To test this hypothesis, Wistar rats were fed either NNS- or sucrose-supplemented yogurt for 17 weeks alongside standard chow (ad libitum). The gut microbiome was assessed by 16S rDNA deep sequencing. Assembly and quantification were conducted using the Brazilian Microbiome Project pipeline for Ion Torrent data with modifications. Statistical analyses were performed in the R software environment. We found that chronic feeding of a commercial NNS-sweetened yogurt to Wistar rats, within the recommended dose range, did not significantly modify gut microbiota composition in comparison to sucrose-sweetened yogurt. Our findings do not support the hypothesis that moderate exposure to NNS is associated with changes in gut microbiota pattern compared to sucrose, at least in this experimental model.

摘要：无营养甜味剂（non-nutritive sweeteners, NNS）对肠道菌群（gut microbiota）的影响因可能对体重增加、胰岛素抵抗及炎症产生潜在作用，正成为日益受关注的研究热点。已有研究表明，饲喂糖精（saccharin）的大小鼠会出现体重增加与代谢紊乱，该变化可能与肠道菌群改变相关。本研究假设，与蔗糖（sucrose）暴露相比，长期接触商用无营养甜味剂会改变Wistar大鼠（Wistar rats）的肠道菌群组成。为验证该假设，本研究将Wistar大鼠分为两组，分别饲喂添加了商用无营养甜味剂或蔗糖的酸奶，并配合标准饲料自由采食，持续17周。采用16S rDNA高通量测序（16S rDNA deep sequencing）对肠道菌群进行分析，使用经改良的巴西微生物组计划（Brazilian Microbiome Project）分析流程处理Ion Torrent测序数据以完成菌群组装与定量。统计分析在R软件环境中完成。研究结果显示，在推荐剂量范围内，长期饲喂商用无营养甜味剂增甜酸奶的Wistar大鼠，其肠道菌群组成与饲喂蔗糖增甜酸奶的大鼠相比无显著改变。本研究结果不支持“与蔗糖相比，适度暴露于无营养甜味剂会改变肠道菌群模式”这一假设，至少在本实验模型中是如此。