NRG was reported to be a Smad3‐specific inhibitor and could suppress the TGF‐β1‐induced ECM protein expression in cultured rat HSCs (Liu, Wang, et al., 2006) and CCl4‐induced rat liver fibrosis model (Hernandez‐Aquino et al., 2019). Here, SMAD3 is linked to Hepatic fibrosis.