Gut Microbiota Characteristics of People with Obesity by Meta-Analysis of Existing Datasets

Abstract

Obesity is a complex chronic, relapsing, progressive disease. Association studies have linked microbiome alterations with obesity and overweight. However, the results are not always consistent. An integrated analysis of 4282 fecal samples (2236 control (normal weight) group, 1152 overweight, and 894 simple obesity) was performed to identify obesity-associated microbial markers. Based on a random effects model and a fixed effects model, we calculated the odds ratios of the metrics, including bacterial alpha-diversity, beta-diversity, Bacteroidetes/Firmicutes ratio, common genera, and common pathways, between the simple obesity and control groups as well as the overweight and control groups. The random forest model was trained based on a single dataset at the genus level. Feature selection based on feature importance ranked by mean decrease accuracy and leave-one-out cross-validation was conducted to improve the predictive performance of the models. Chao1 and evenness possessed significant ORs higher than 1.0 between the obesity and control groups. Significant bacterial community differences were observed between the simple obesity and the control. The ratio of Bacteroidetes/Firmicutes was significantly higher in simple obesity patients. The relative abundance of Lachnoclostridium and Faecalitalea were higher in people with simple obesity, while 23 genera, including Christensenellaceae_R-7_group, Akkermansia, Alistipes, and Butyricimonas, etc., were significantly lower. The random forest model achieved a high accuracy (AUC = 0.83). The adenine and adenosine salvage pathway (PWY-6609) and the L-histidine degradation I pathway (HISDEG-PWY) were clustered in obese patients, while amino acid biosynthesis and degradation pathways (HISDEG-PWY, DAPLYSINESYN-PWY) were decreased. This study identified obesity microbial biomarkers, providing fertile targets for the management of obesity.

Shifts and importance of viable bacteria in treatment of DSS-induced ulcerative colitis mice with FMT

“…Fecal microbiota transplantation (FMT) is a novel treatment method which is to transfer the functional microbiota from normal feces to an unbalanced gastrointestinal tract, reconstruct a new intestinal flora, and resume the host function ( Costello et al., 2017 ; Liu et al., 2021 ) This technique has proven effective impact in many microbiota-related metabolic ( Lee et al., 2019 ; Que et al., 2021 ; Gong et al., 2022 ), infectious ( Smillie et al., 2018 ), and inflammatory diseases ( Weingarden and Vaughn, 2017 ; Zhang et al., 2019 ). In recent research, the patients have recurrent Clostridium difficile infection were extremely effective treated by FMT (about 90% cure rate) ( Le Bastard et al., 2018 ).…”

Comparative Gut Microbiome Differences between High and Low Aortic Arch Calcification Score in Patients with Chronic Diseases

“…Lee et al reported that Butyricimonas could prevent high fat diet-induced diabetes and metabolic disorders in mice via the GLP-1 receptor [ 62 ]. Butyricimonas has also been negatively correlated with insulin resistance and obesity in humans [ 63 , 64 ].…”

Abundance of Ruminococcaceae is Associated with Claudin 22 Gene Expression and Body Weight in Mice

“…The family Ruminococcaceae and the genus Ruminococcus are involved in alcohol metabolism [39] , adipokine metabolism [40] , cirrhosis [41] , acute-on-chronic liver failure [42] , allergy [43,44] , antibiotic biosynthesis [45] , in ammation [46] , and cardiovascular risk [47] . However, the involvement of these bacteria in BW changes is controversial, with reports stating that individuals with obesity have increased [48][49][50] or decreased [51][52][53] abundance of Ruminococcaceae or that it varies with species [54] . As for the mechanism by which Ruminococcaceae members are involved in host BW regulation, it has been suggested that they degrade various polysaccharides to produce short-chain fatty acids (SCFAs) [55] .…”