TLR4 and metabolic dysfunction-associated steatohepatitis: In addition, qPCR was used to measure the mRNA expression of IL-1β, IL-6, and TNF-α in the liver, important downstream target genes of TLR4/NF-κB, and the results showed that the mRNA expression of IL-1β, IL-6, and TNF-α was upregulated in the liver tissues of the NASH mice compared to that in the control group.