ACE and kidney disorder: Notably, the classical RAS driven by ACE has been shown to be associated with tissue fibrosis in many diseases, including chronic heart disease, kidney disease and diabetes (Warner et al., 2020), and the protective RAS regulated by ACE2 could counteract or modulate these effects and is a promising direction for antifibrotic therapy (Mak et al., 2015; Santos et al., 2018).