Gut microbiota and obesity: New insights

Abstract

Obesity is a pathology whose incidence is increasing throughout the world. There are many pathologies associated with obesity. In recent years, the influence of the microbiota on both health and pathological states has been known. There is growing information related to changes in the microbiome and obesity, as well as its associated pathologies. Changes associated with age, exercise, and weight changes have been described. In addition, metabolic changes associated with the microbiota, bariatric surgery, and fecal matter transplantation are described. In this review, we summarize the biology and physiology of microbiota in obese patients, its role in the pathophysiology of several disorders associated, and the emerging therapeutic applications of prebiotics, probiotics, and fecal microbiota transplantation.

Keywords: gut; microbiome; microbiota; obesity; overweight.

Figure 1

Microbiota modification in overweight and obese humans. Predominant microbiota composition at the phylum and genus level in relation to thin.

Figure 2

Microbial taxa in obese subjects with metabolic abnormalities.

Figure 3

Disruption in intestinal microbiota composition and treatment by FMT, BS, probiotics, prebiotics and synbiotics. Schematic representation of altered GM composition in obesity and MS. In people metabolically healthy, the GM and enterocyte are normal (A). In obesity, altered GM composition (diet, drugs, stress, etc.) inhibits Fiaf in epithelial cells and increases LPL activity; this leads to increased synthesis of triglycerides, fatty acids, and fat storage in adipocytes (B,C); the opposite effect can be seen after treatment (RYGB, VSG) (D–F) in which the amount of Fiaf inhibits LPL [described in (J)]. However, there is a risk of SIBO (G,H). Prebiotics, probiotics, and synbiotics are an alternative to treatment and have been described to achieve a balanced gut microbiota and lead to a healthy metabolic state (I,J). MS, Metabolic Syndrome; GM, Gut microbiota; Fiaf, Fasting-Induced Adipose Factor or Angptl4; LPL, Lipoprotein lipase; RYGB, Roux-en-Y Gastric Bypass; VSG, Vertical Sleeve Gastrectomy; SIBO, Small Intestinal Bacterial Overgrowth.