Distinct Regulation of U-ACE2 and P-ACE2 (urinary and Plasma Angiotensin-Converting Enzyme 2) in a Japanese General Population

Severe acute respiratory syndrome coronavirus 2 in coronavirus disease 2019 invades the host through ACE (angiotensin-converting enzyme) 2 as the host cellular receptor for a viral spike protein. ACE2 converts angiotensin II to angiotensin-(1–7) and cleaved ACE2 is detectable in urine and plasma. However, regulation of U-ACE2 (urinary ACE2) and P-ACE2 (plasma ACE2) and their alterations by renin-angiotensin-aldosterone system inhibitors remain unclear. We simultaneously investigated U-ACE2 and P-ACE2 in 605 Japanese participants (male/female: 280/325, mean age: 65±15 years) in the Tanno-Sobetsu cohort study in 2017. Males had significantly lower U-ACE2 and higher P-ACE2 than did females. There was no significant correlation between U-ACE2 and P-ACE2. P-ACE2 was significantly lower in subjects treated with renin-angiotensin-aldosterone system inhibitors than in those not treated with renin-angiotensin-aldosterone system inhibitors, but there was no significant difference in U-ACE2 between the groups. Multivariable regression analyses showed that female sex, high levels of systolic blood pressure, hemoglobin A1c, and urinary albumin-to-creatinine ratio, and low uric acid level were independent predictors of high U-ACE2 level and that high levels of γ-glutamyl transpeptidase, estimated glomerular filtration rate, and uric acid were independent predictors of high P-ACE2 level. In conclusion, U-ACE2 and P-ACE2 are distinctly regulated and the use of renin-angiotensin-aldosterone system inhibitors is not an independent predictor of their levels in a Japanese general population. U-ACE2 is associated with high blood pressure, high glucose level, and microalbuminuria, and low urate level, whereas P-ACE2 is associated with liver dysfunction, high glomerular filtration rate, and high urate level.