ACTA1 and metabolic dysfunction-associated steatohepatitis: There were no significant differences in hepatic collagen deposition between groups upon image analysis of Picro Sirius Red-stained sections (Figs. 4i, j and 5f), however, a higher fraction of α-SMA-positive (α-SMA+) cells (indicating activation of hepatic stellate cells [42]) were observed in livers of NASH-STZ animals compared to both CTRL and NASH (p < 0.0001, Fig. 5d) and was decreased after treatment with insulin (p < 0.001, Figs. 4g, h and 5d).