ACE2 as therapy for glomerular disease: the devil is in the detail.

Angiotensin-converting enzyme 2 cleaves angiotensin (Ang) II to Ang(1-7), which antagonizes the deleterious effects of Ang II. In this issue, 2 groups administered angiotensin-converting enzyme 2 in murine models of kidney disease. Angiotensin-converting enzyme 2 did not improve glomerular injury in 2 models of mild diabetic nephropathy but was partially protective in an Alport syndrome model. These discrepant findings may be explained by the inability of angiotensin-converting enzyme 2 to reach the urinary space in the absence of severe proteinuria.