Transient hepatic Trim21 silencing resulted in a moderate rise in inflammatory (TNF-α, F4/80) and fibrosis (Col1a1) markers, consistent with elevated steatosis, though it resulted in no changes in αSMA expression, JNK/TAK1 signaling, or plasma ALT levels in livers of NASH mice in which Trim21 was silenced compared with controls (Supplemental Figure 6, F–K). Here, MAPK8 is linked to metabolic dysfunction-associated steatohepatitis.