Obesity is one of the largest current public health problems. Recent studies suggest that persistent changes in the intestinal microbiota (dysbiosis) can eventually lead to obesity. A stable core of intestinal microbiota exists, primarily composed of the phyla Firmicutes and Bacteroidetes, but their proportions can be altered by antibiotics. Such changes appear to not only alter host energy consumption but also modify host satiety mechanisms. Our study evaluated possible changes in the gut microbiota caused by oral administration of tetracycline, both alone or in combination with Lactobacillus gasseri in rats. Zoometric analyses were conducted and qPCR of fecal samples were analyzed to allow comparison before and during treatment regarding Firmicutes Bacteroidetes proportions. The results showed increased weight and body mass index (BMI) in animals treated with tetracycline alone (P < 0.05) when compared to the group that received tetracycline with probiotic, except for BMI in phase two when there was no statistical significance. Molecular analysis showed that after animals were treated with tetracycline, Firmicutes predominated over Bacteroidetes bacteria, which was coincident with increased weight and BMI. Probiotic addition may have minimized tetracycline dysbiosis, preventing excessive weight gain. Changes in microbiota caused by antibiotics have been shown to be an important factor related to childhood obesity. Microbiological manipulation of microbiota can play an important role in weight control, especially with antibiotic acting microbiota. More studies are needed to elucidate this mechanism.

中文翻译：

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大鼠服用四环素和加氏乳杆菌后微生物群和体重变化的评价

肥胖是当前最大的公共卫生问题之一。最近的研究表明，肠道微生物群的持续变化（生态失调）最终会导致肥胖。存在稳定的肠道微生物群核心，主要由厚壁菌门和拟杆菌门组成，但它们的比例可以通过抗生素改变。这种变化似乎不仅会改变宿主的能量消耗，还会改变宿主的饱腹感机制。我们的研究评估了大鼠口服四环素（单独或与加氏乳杆菌）可能引起的肠道微生物群变化。进行了缩放分析并分析了粪便样本的 qPCR，以便在治疗前和治疗期间比较厚壁菌的拟杆菌比例。结果显示，与接受四环素和益生菌的组相比，单独接受四环素治疗的动物的体重和体重指数 (BMI) 增加 (P < 0.05)，但第二阶段的 BMI 没有统计学意义。分子分析表明，动物接受四环素治疗后，厚壁菌门占优势，而拟杆菌门菌则占优势，这与体重和体重指数增加相吻合。添加益生菌可能最大限度地减少四环素的生态失调，防止体重过度增加。抗生素引起的微生物群变化已被证明是与儿童肥胖相关的重要因素。微生物群的微生物操作可以在体重控制中发挥重要作用，尤其是具有抗生素作用的微生物群。需要更多的研究来阐明这种机制。