Cross-Talk Between Gut Microbiota and Adipose Tissues in Obesity and Related Metabolic Diseases

Abstract

The rapid increase of obesity and associated diseases has become a major global health problem. Adipose tissues are critical for whole-body homeostasis. The gut microbiota has been recognized as a significant environmental factor in the maintenance of energy homeostasis and host immunity. A growing body of evidence suggests that the gut microbiota regulates host metabolism through a close cross-talk with adipose tissues. It modulates energy expenditure and alleviates obesity by promoting energy expenditure, but it also produces specific metabolites and structural components that may act as the central factors in the pathogenesis of inflammation, insulin resistance, and obesity. Understanding the relationship between gut microbiota and adipose tissues may provide potential intervention strategies to treat obesity and associated diseases. In this review, we focus on recent advances in the gut microbiota and its actions on adipose tissues and highlight the joint actions of the gut microbiota and adipose tissue with each other in the regulation of energy metabolism.

Keywords: adipose tissues; energy metabolism; gut microbiota; inflammation; obesity.

Figure 1

The crosstalk between gut microbiota and adipose tissues. On the one hand, the gut microbiota and microbial-derived metabolites may mediate the external factors, such as dietary foods, to regulate white adipose tissue (WAT) expansion, inflammation, and insulin resistance in obesity. Different diets may have different effects on the gut microbiota, such as low carbohydrate diet (LCD) (22) can increase Bacteroidaceae Bacteroides and reduce body weight effectively; whereas western diet (WD) (24) or high-fat diet (HFD) (43, 76) can increase dysbiosis of gut microbiota and inflammation of adipose tissues; and ketogenic diet (KD) (117) can increase A. muciniphila, Lactobacillus and regulate lipid metabolism through PPARα/FGF21 pathway. On the other hand, the gut microbiota and its metabolites may mediate environmental temperature, intermittent fasting (IF), or caloric restriction (CR) in the process of energy expenditure by promoting browning and thermogenesis of beige and brown adipose tissue (BAT). In the meantime, some adipokines, including leptin, adiponectin, FGF21, and apelin, produced by adipose tissues can act on the gut microbiota to modulate its composition.