Table 1.
Microbiota changes associated with obesity.
| Reference | Characteristics | Disease | Method | Primary Results |
|---|---|---|---|---|
| Turnbaugh et al., 2009 [34] | 154 adult female monozygotic and dizygotic twin pairs concordant for leanness or obesity | Obesity | Sequencing (16S rRNA) |
Gut microbiomes are shared among family members, but the gut microbial community varies in each individual. |
| Ignacio et al., 2016 [40] | Correlation between BMI and fecal microbiota in 84 children | Obesity | qRT-PCR | Significant association between the number of Lactobacillus spp. and B. fragilis group members and BMI. |
| Riva et al., 2017 [44] | Characterization of the gut microbiota in 78 obese and normal-weight children aged 6 to 16 | Obesity | Sequencing (16S rRNA) |
Elevated levels of Firmicutes and depleted levels of Bacteroidetes. |
| Nicolucci et al., 2017 [48] | 42 obese children who received either oligofructose-enriched inulin or placebo | Obesity | Sequencing (16S rRNA) |
Significant increases in species of the genus Bifidobacterium and decreases in B. vulgatus within the group that consumed oligofructose-enriched inulin. |
| Zhang et al., 2015 [54] | Intervention trial in 38 Prader-Willi syndrome and simple obesity children. | Prader-Willi syndrome and obesity | Analysis of prevalent bacterial draft genomes assembled directly from metagenomic datasets | Non-digestible carbohydrates induced significant weight loss and concomitant structural changes in the gut microbiota. |
| Bai et al., 2018 [55] | 267 children (7–18 years old) analyzed according to their lifestyles | Obesity | Sequencing (16S rRNA) |
Lower BMI and exercise frequency were associated with depleted Actinobacteria; Proteobacteria was significantly enriched in individuals with higher BMI levels; and Firmicutes was significantly enriched in individuals participating in frequent exercise. |
| Rampelli et al., 2018 [56] | 70 children analyzed in a two-time point 4-year prospective study | Pre-obese | Sequencing (16S rRNA) |
Pre-obese dysbiosis and unhealthy diets were correlated and suggested to be predictors of obesity. |
| Tremaroli et al., 2015 [61] | Gut microbiome analysis of 14 women 9.4 years after bariatric surgery was performed | Obesity | High-quality Illumina reads alignment analysis | Bariatric surgery induces long-term alterations in the human gut microbiome. Surgically altered microbiomes contribute to fat mass regulation. |
| Palleja et al., 2016 [63] | Gut microbiome analysis 1 and 3 months after bariatric surgery in 13 patients | Obesity | Shotgun metagenomic sequencing | 31 microbial species showed altered relative abundances within the first 3 months, 16 of which maintained their altered relative abundances 1 year after surgery. F. prausnitzii was the only species that decreased in relative abundance. |
| Liu et al., 2017 [64] | Gut microbiome analysis of obese and post-bariatric intervention individuals in a cohort of 257 lean and obese young individuals | Obesity | Metagenome-wide association | Abundance of B. thetaiotaomicron was markedly decreased in obese individuals. Bariatric surgery intervention reversed obesity associated microbial alterations, including the decreased abundance of B. thetaiotaomicron. |
| Aron-Wisnewsky et al. [22] | 61 severely obese subjects of whom 24 were followed 1, 3, and 12 months post-bariatric surgery | Obesity | Shotgun metagenomics | Although bariatric surgery increased MGR one year after surgery, most RYGB patients remained with low MGR one year postsurgery. |
| Del Chierico et al., 2018 [67] | Gut microbiome analysis of 69 adolescent and adult patients | Obesity | Sequencing (16S rRNA) |
Microbial markers, F. prausnitzii and Actinomyces assigned to the microbiota of obese adolescents. Parabacteroides, Rikenellaceae, Bacteroides caccae, Barnesiellaceae and Oscillospira were assigned to the microbiota of normal weight adolescents. |
| Le Chatelier et al., 2013 [68] | Gut microbiome analysis of 292 adult patients | Obesity | Sequencing (16S rRNA) |
Individuals with low bacterial richness are characterized by increased overall adiposity compared to high bacterial richness individuals. |
Abbreviations: BMI: body mass-index; MGR: microbial gene richness; qRT-PCR: quantitative polymerase chain reaction; rRNA: ribosomal ribonucleic acid; RYGB: Roux-en-Y gastric bypass.