title: Urinary ACE2 is associated with urinary L-FABP and albuminuria in patients with chronic kidney disease.
abstract: OBJECTIVE
  Angiotensin-converting enzyme 2 (ACE2) is expressed in the kidney and may be a renoprotective enzyme since it converts angiotensin (Ang) II to Ang-(1-7). In addition, ACE2 has been detected in urine from patients with chronic kidney disease (CKD). The aim of this study was to determine the urinary ACE2 levels in patients with various stages of CKD and to identify the factors associated with the presence of ACE2.
  
  
  METHODS
  We assessed 152 patients with CKD stage G1-G4. The patients were classified according to the presence or absence of diabetes mellitus (DM) (DM group, n = 72; non-DM group, n = 80) and according to the estimated glomerular filtration rate (CKD stage G1/2 group, n = 40; CKD stage G3 group, n = 74; and CKD stage G4 group, n = 38). Parameters were urinary ACE2, urinary albumin/ creatinine ratio (UACR), urinary liver-type fatty acid binding protein (L-FABP), estimated glomerular filtration rate, and other factors determined to be associated with elevated urinary ACE2.
  
  
  RESULTS
  Urinary ACE2 was significantly higher in patients with diabetes (p = 0.01) and in patients with CKD stage G4 compared with stages G1-G3 (p < 0.0001). Multivariable regression analysis revealed that urinary L-FABP and UACR were significantly associated with urinary ACE2 levels, indicating that urinary ACE2 is increased in patients with diabetes and advanced stage CKD.
  
  
  CONCLUSIONS
  ACE2 might continuously protect from both glomerular and tubulointerstitial injury during CKD progression. Taken together, urinary ACE2 might be a marker of kidney renin-angiotensin system activation in such patients.
authors.affiliation: Division of Nephrology, Hypertension and Endocrinology, Department of Internal Medicine, Nihon University School of Medicine , Tokyo , Japan.
authors.forename: Masanori
authors.initials: M
authors.lastname: Abe
authors.forename: Noriaki
authors.initials: N
authors.lastname: Maruyama
authors.forename: Osamu
authors.initials: O
authors.lastname: Oikawa
authors.forename: Takashi
authors.initials: T
authors.lastname: Maruyama
authors.forename: Kazuyoshi
authors.initials: K
authors.lastname: Okada
authors.forename: Masayoshi
authors.initials: M
authors.lastname: Soma
mesh_terms: D000368:Aged; D000419:Albuminuria / Q000150:complications* / Q000503:physiopathology / Q000652:urine*; D000085962:Angiotensin-Converting Enzyme 2; D003710:Demography; D003920:Diabetes Mellitus / Q000652:urine; D050556:Fatty Acid-Binding Proteins / Q000652:urine*; D005260:Female; D005919:Glomerular Filtration Rate; D006801:Humans; D016014:Linear Models; D008297:Male; D015999:Multivariate Analysis; D007703:Peptidyl-Dipeptidase A / Q000652:urine*; D051436:Renal Insufficiency, Chronic / Q000150:complications* / Q000503:physiopathology / Q000652:urine*; D012307:Risk Factors
chemical_list: D050556:Fatty Acid-Binding Proteins; D007703:Peptidyl-Dipeptidase A; C000705307:ACE2 protein, human; D000085962:Angiotensin-Converting Enzyme 2
keywords: Albuminuria; angiotensin-converting enzyme 2; chronic kidney disease; urinary liver-type fatty acid binding protein