OSBPL8 and metabolic dysfunction-associated steatohepatitis: In this study, we demonstrated that anti-inflammatory bone marrow-derived macrophages inhibit inflammation and attenuate lipotoxicity by secreting Osbpl8-enriched extracellular vesicles and restoring normal liver function by regulating endoplasmic reticulum stress-related mechanisms in diet-induced MASH, which provides new ideas for the treatment of early-stage MASH.