d to provide a better background for future experimental and clinical investigations.

ACE System and ACE2 Discovery
Human Angiotensin-converting enzyme (ACE) belongs to the M2 gluzincin family of metalloproteinases and (Ehlers and Riordan, 1989; Masuyer et al., 2014) exists in two forms, namely somatic ACE (sACE) and germinal ACE (tACE).