FIGURE 7.

Potential mechanisms of pro-DKD effect of TMAO. Foods like red meat, eggs and milk are digested and absorbed by the gastrointestinal tract, subsequently metabolized under the action of gut microbiota and then oxidized by the liver to form TMAO to enter the bloodstream. TMAO entered the kidney tissue with the blood, and facilitated renal fibrosis by increasing pro-fibrotic factor TGF-β₁ and its downstream molecule α-SMA. TMAO may also activated the NLRP3 inflammasome to cause the release of IL-1β and IL-18 to promote renal inflammation. These effects together aggravated the progression of DKD.