In conclusion, YLZD exerts a therapeutical effect on HFD-induced NAFLD by modulation of SIRT1/Nrf2 signaling pathway, which corresponds with shaping gut microbiota, increasing the content of SCFAs-producing bacteria such as Christensenellaceae, and upregulating SCFAs such as BA levels in NAFLD rats. Here, SIRT1 is linked to metabolic dysfunction-associated steatotic liver disease.