ACE2 and diabetes mellitus: The presence of increased urinary ACE2 fragments in the absence of albuminuria, coupled with evidence that infusion of recombinant ACE2 in mice with diabetes does not increase urinary ACE2 levels (Wysocki et al., 2013), suggests that ACE2 shedding from the apical surface of tubular epithelial cells accounts for a major component of urinary ACE2 content.