ACTA2 and metabolic dysfunction-associated steatohepatitis: In contrast, expression of α-2 actin (Acta2), a marker of hepatic stellate cell (HSC) activation, was increased in C3H mice but reduced in A/J mice, while connective tissue growth factor (Ccn2/Ctgf) expression was unaffected by the NASH diet in all strains (Fig. 2D,E).