Microbiota intestinal : impacto das intervenções para sobrepeso ou obesidade

• Autor(a) principal: Seganfredo, Fernanda Braga
• Data de Publicação: 2017
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: Biblioteca Digital de Teses e Dissertações da PUC_RS
• Texto Completo: http://tede2.pucrs.br/tede2/handle/tede/7827
• topic: Dietoterapia; Cirurgia Bariátrica; Microbioma Gastrointestinal; Suplementos Nutricionais; CIENCIAS DA SAUDE::MEDICINA

Background: Obesity is a worldwide concern of growing proportions, that increases both morbidity and mortality of patients, despite having economic impact. Imbalances in the gut microbiota - the bacteria that inhabit the intestines - are central to the pathogenesis of obesity. Objectives: To assess the association between the gut microbiota and weight loss in overweight/obese adults and its potential manipulation as a target for treating obesity. Methodology: This study is a systematic review review that identified studies using the keywords ‘overweight’ or ‘obesity’ and ‘microbiota’ and related terms. Results: 43 papers were identified. Among these studies, 17 used dietary interventions, 11 used bariatric surgery and 15 used microbiota manipulation. The studies differed in their methodologies as well as their intervention lengths. Restrictive diets decreased the microbiota abundance, correlated with nutrient deficiency rather than weight loss and generally reduced the butyrate producers Firmicutes, Lactobacillus sp. and Bifidobacterium sp. The impact of surgical intervention depended on the given technique and showed a similar effect on butyrate producers, in addition to increasing the presence of the Proteobacteria phylum, which is related to changes in the intestinal absorptive surface, pH and digestion time. Probiotics differed in strain and duration with diverse effects on the microbiota, and they tended to reduce body fat. Prebiotics had a bifidogenic effect and increased butyrate producers, likely due to cross-feeding interactions, contributing to the gut barrier and improving metabolic outcomes. Conclusions: All of the interventions under consideration had impacts on the gut microbiota, although they did not always correlate with weight loss. These results show that restrictive diets and bariatric surgery reduce microbial abundance and promote changes in microbial composition that could have long-term detrimental effects on the colon. In contrast, prebiotics might restore a healthy microbiome and reduce body fat.