MSC-Exo extracted from human umbilical cords stimulated M2 polarization, exhibited downregulation of pro-inflammatory factors such as TNF-α, IL-6 and IL-1β, and detected high expression of PPARα in liver tissue, thereby alleviating methionine-cholesterol deficient (MCD) diet-induced progression to NASH in NAFLD mice (177). This evidence concerns the gene TNF and metabolic dysfunction-associated steatohepatitis.