Fig. 2.

The gut microbiota participates in material metabolism to produce metabolites (created with BioRender.com). The gut microbiota can affect the metabolism of glucose, lipids, and proteins by generating a series of metabolites and activating downstream signaling pathways. Abbreviations: SCFAs: short-chain fatty acids; BAs, bile acids; TMAO: trimethylamine N-oxide; BCAAs: branched-chain amino acids; GPR, G protein-coupled receptor; Olfr78: olfactory receptor 78; NF-κB: nuclear factor kappa-B; BSH: bile salt hydrolase; FMO3: flavin monooxygenase 3; FXR: farnesoid X receptor; TGR5: Takeda-G-protein receptor 5; mTORC1: mammalian target of rapamycin complex 1