NFKB1 and metabolic dysfunction-associated steatohepatitis: In their study, Aizawa et al. directly induced MASH in a model in ferrets via the intraperitoneal (ip) injection of NNK (50 mg/kg BW, once a month for four months), which resulted in severe inflammatory cell infiltration, hepatic fat accumulation, hepatocellular ballooning-like degeneration, and the increased expression of injurious NF-κB, CYP2E1 [198].