Centro de Estudos em Estresse Oxidativo-Departamento de Bioquímica - Instituto de Ciências Básicas da Saúde-Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS, Brasil.
Departamento de Ingeniería Civil y Ambiental-Universidad de la Costa, Barranquilla, Atlántico, Colombia.
Int J Obes (Lond). 2018 Mar;42(3):525-534. doi: 10.1038/ijo.2017.225. Epub 2017 Sep 12.
BACKGROUND/OBJECTIVES: Obesity is a metabolic disorder that predisposes patients to numerous diseases and has become a major global public-health concern. Animal models of diet-induced obesity (DIO) are frequently used to study obesity, but which DIO model most accurately reflects the pathology of human obesity remains unclear. In this study, we designed a diet based on the human Western diet (WD) and compared it with the cafeteria diet (CAF) and high-fat diet (HFD) in order to evaluate which diet most closely mirrors human obesity.
Wistar rats were fed four different diets (WD, CAF, HFD and a low-fat diet) for 18 weeks. Metabolic parameters and gut microbiota changes were then characterized.
Rats fed the four different diets exhibited completely different phenotypes, highlighting the importance of diet selection. This study also revealed that WD most effectively induced obesity and obesity-related disorders, and thus proved to be a robust model of human obesity. Moreover, WD-fed rats developed obesity and obesity-related comorbidities independent of major alterations in gut microbiota composition (dysbiosis), whereas CAF-fed rats developed the greatest dysbiosis independent of obesity. We also characterized gut microbiota after feeding on these four different diets and identified five genera that might be involved in the pathogenesis of obesity.
These data suggest that diet, and not the obese state, was the major driving force behind gut microbiota changes. Moreover, the marked dysbiosis observed in CAF-fed rats might have resulted from the presence of several additives present in the CAF diet, or even a lack of essential vitamins and minerals. Based on our findings, we recommend the use of the prototypic WD (designed here) in DIO models. Conversely, CAF could be used to investigate the effects of excessive consumption of industrially produced and highly processed foods, which are characteristic of Western society.
背景/目的：肥胖是一种代谢紊乱，使患者易患多种疾病，已成为一个主要的全球公共卫生关注点。饮食诱导肥胖（DIO）动物模型常用于研究肥胖，但哪种 DIO 模型最能准确反映人类肥胖的病理仍不清楚。在这项研究中，我们设计了一种基于人类西方饮食（WD）的饮食，并将其与自助餐厅饮食（CAF）和高脂肪饮食（HFD）进行了比较，以评估哪种饮食最能反映人类肥胖。
Wistar 大鼠分别用四种不同的饮食（WD、CAF、HFD 和低脂肪饮食）喂养 18 周。然后，对代谢参数和肠道微生物群的变化进行了特征分析。
用四种不同饮食喂养的大鼠表现出完全不同的表型，突出了饮食选择的重要性。这项研究还表明，WD 最有效地诱导肥胖和肥胖相关疾病，因此被证明是一种强有力的人类肥胖模型。此外，WD 喂养的大鼠在不改变肠道微生物群组成（失调）的情况下发展为肥胖和肥胖相关的合并症，而 CAF 喂养的大鼠在不肥胖的情况下发展出最大的失调。我们还对这四种不同饮食喂养后的肠道微生物群进行了特征分析，并鉴定出可能参与肥胖发病机制的五个属。
这些数据表明，是饮食而不是肥胖状态，是肠道微生物群变化的主要驱动力。此外，在 CAF 喂养的大鼠中观察到的明显失调可能是由于 CAF 饮食中存在几种添加剂，甚至是缺乏必需的维生素和矿物质所致。根据我们的发现，我们建议在 DIO 模型中使用原型 WD（这里设计的）。相反，CAF 可用于研究过度消费工业生产和高度加工食品的影响，这是西方社会的特征。
