TGFB1 and metabolic dysfunction-associated steatohepatitis: In addition, several preliminary studies in NASH and chronic hepatitis C observed that the angiotensin receptor antagonist, losartan reduced hepatic fibrosis, which was associated with reduced TGF-β1 and procollagen levels (Yokohama et al., 2004; Colmenero et al., 2009; Terui et al., 2002).