Nox4 modulates collagen production stimulated by transforming growth factor β1 in vivo and in vitro

► We examined the role of Nox4 on collagen accumulation in vivo and vitro. ► TGFβ1-induced collagen accumulation in sponges cotreated with Adv-Nox4ΔNADPH implanted in mice. ► Suppressing Nox4 reduced collagen accumulation in vivo. ► Inhibiting Nox4 gene expression and ROS release reduced collagen synthesis in vitro. ► Nox4 acts as an intermediary effector to facilitate TGFβ-induced collagen synthesis.