TLR4 and metabolic dysfunction-associated steatotic liver disease: A growing body of evidence indicates that bacterial endotoxins, such as LPS, are closely related to MASLD.37 Endotoxins stimulate cells in the liver by releasing inflammatory cytokines and chemokines by a Tlr-4-mediated mechanism.38 We have shown in in vitro studies that IPA and IAA treatment directly affect macrophages by reducing endotoxin signaling.